U.S. patent application number 13/624351 was filed with the patent office on 2014-03-27 for manifolds and methods and systems using them.
The applicant listed for this patent is Hamid Badiei, James Botelho, Brian Chan. Invention is credited to Hamid Badiei, James Botelho, Brian Chan.
Application Number | 20140083544 13/624351 |
Document ID | / |
Family ID | 50337686 |
Filed Date | 2014-03-27 |
United States Patent
Application |
20140083544 |
Kind Code |
A1 |
Chan; Brian ; et
al. |
March 27, 2014 |
MANIFOLDS AND METHODS AND SYSTEMS USING THEM
Abstract
Certain embodiments described herein are directed to manifolds
that comprise a moveable, internal sealing member that can be used
to engage one or more ports of the manifold and prevent or reduce
fluid flow from the engaged port into the manifold. In certain
examples, the manifold can be used in a mass spectrometer to
control fluid flow from an interface and a turbomolecular pump.
Inventors: |
Chan; Brian; (Markham,
CA) ; Badiei; Hamid; (Woodbridge, CA) ;
Botelho; James; (Danbury, CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chan; Brian
Badiei; Hamid
Botelho; James |
Markham
Woodbridge
Danbury |
CT |
CA
CA
US |
|
|
Family ID: |
50337686 |
Appl. No.: |
13/624351 |
Filed: |
September 21, 2012 |
Current U.S.
Class: |
137/872 |
Current CPC
Class: |
G05D 7/03 20130101; F16K
11/0655 20130101; Y10T 137/87788 20150401; F16K 41/10 20130101;
F16K 11/044 20130101 |
Class at
Publication: |
137/872 |
International
Class: |
G05D 7/03 20060101
G05D007/03 |
Claims
1. A vacuum manifold comprising: a housing comprising a first port
configured to provide fluidic coupling between a sampling interface
line and the manifold; a second port on the housing that is
configured to provide fluidic coupling between a pump backing line
and the manifold; a third port on a housing that is configured to
provide fluidic coupling between a mechanical roughing pump and the
manifold; and a moveable sealing member in the vacuum manifold, in
which the moveable sealing member comprises a first position
effective to permit fluid flow between the first port and the third
port and effective to block fluid flow from the second port, in
which the moveable sealing member comprises a second position
effective to permit fluid flow between the second port and the
third port and effective to block fluid flow from the first port,
in which the moveable sealing member further comprises a third
position effective to permit fluid flow between the first port, the
second port and the third port.
2. The vacuum manifold of claim 1, in which the moveable sealing
member comprises a sealing device configured to engage the second
port in the first position of the moveable sealing member to
provide a substantially fluid tight seal between the sealing member
and the second port.
3. The vacuum manifold of claim 2, in which the sealing device is
configured to engage the first port in the second position of the
moveable sealing member to provide a substantially fluid tight seal
between the sealing member and the first port.
4. The vacuum manifold of claim 3, in which the sealing device
comprises a first O-ring that is between the sealing device and the
second port when the sealing member is in the first position, and a
second O-ring that is between the sealing device and the first port
when the sealing member is in the second position.
5. The vacuum manifold of claim 1, further comprising an actuator
coupled to the moveable sealing member.
6. The vacuum manifold of claim 5, in which the actuator comprises
a motor.
7. The vacuum manifold of claim 5, in which the sealing member
comprises a plunger coupled to the actuator.
8. The vacuum manifold of claim 7, in which the plunger comprises a
longitudinal shaft coupled to the actuator and a disk coupled to
the longitudinal shaft in an orthogonal direction to the
longitudinal shaft, the disk configured to engage an interior
manifold surface adjacent to the first port in the second position
of the moveable sealing member to provide a substantially fluid
tight seal between the plunger and the first port to block fluid
flow into the manifold from the sampling interface line, in which
the disk is further configured to engage an interior manifold
surface adjacent to the second port in the first position of the
moveable sealing member to provide a substantially fluid tight seal
between the plunger and the second port to block fluid flow into
the manifold from the pump backing line.
9. The vacuum manifold of claim 7, in which the plunger comprises a
first longitudinal shaft of a first outer diameter coupled to the
actuator and a second longitudinal shaft of a second outer
diameter, greater than the first outer diameter, coupled to the
first longitudinal shaft, in which an end of the second
longitudinal shaft is configured to engage an interior manifold
surface adjacent to the first port in the second position of the
moveable sealing member to provide a substantially fluid tight seal
between the plunger and the first port to block fluid flow into the
manifold from the sampling interface line, in which an opposite end
of the second longitudinal shaft is configured to engage an
interior manifold surface adjacent to the second port in the first
position of the moveable sealing member to provide a substantially
fluid tight seal between the plunger and the second port to block
fluid flow into the manifold from the pump backing line.
10. The vacuum manifold of claim 9, in which the second outer
diameter is selected to be at least 5% greater than a diameter of
the first port.
11. The vacuum manifold of claim 7, in which the plunger comprises
a longitudinal shaft coupled to the actuator and a barbell end
coupled to the longitudinal shaft, in which a first surface of the
barbell end is configured to engage an interior manifold surface
adjacent to the first port in the second position of the moveable
sealing member to provide a substantially fluid tight seal between
the engaged first surface and the first port to block fluid flow
into the manifold from the sampling interface line, in which a
second surface of the barbell end is configured to engage an
interior manifold surface adjacent to the second port in the first
position of the moveable sealing member to provide a substantially
fluid tight seal between the engaged second surface and the second
port to block fluid flow into the manifold from the backing
line.
12. The vacuum manifold of claim 1, in which the third position of
the sealing member is selected to position a terminal end of the
sealing member closer to the first port of manifold than to the
second port of the manifold.
13. The vacuum manifold of claim 1, in which the third position of
the sealing member is selected to provide a selected fluidic
conductance.
14. The vacuum manifold of claim 1, in which the sealing member
comprises an actuator coupled to a longitudinal shaft, and a disk
coupled to the longitudinal shaft in an orthogonal direction, in
which the longitudinal shaft comprises a bellows effective to
provide a substantially fluid tight seal between the housing and a
site of the housing where the longitudinal shaft of the sealing
member enters the housing.
15. The vacuum manifold of claim 14, in which the actuator
comprises a motor.
16. The vacuum manifold of claim 15, in which the second position
of the sealing member is provided after a fixed amount of steps
using the motor.
17. The vacuum manifold of claim 1, in which the sealing member
comprises a substantially inert material.
18. The vacuum manifold of claim 17, in which the substantially
inert material is a plastic, a stainless steel,
polytetrafluoroethylene, aluminum, titanium or an Inconel
alloy.
19. The vacuum manifold of claim 1, in which the sealing member is
configured for use with an inductively coupled plasma mass
spectrometer system, in which the sealing member is configured to
be in the first position when a vacuum is off and the plasma is
off, in which the sealing member is configured to be in the second
position when the vacuum is on and when the plasma is off, and in
which the sealing member is configured to be in the third position
when the plasma is on.
20. The vacuum manifold of claim 1, in which the vacuum manifold is
configured as a valveless manifold.
21-138. (canceled)
Description
TECHNOLOGICAL FIELD
[0001] Certain features, aspects and embodiments are directed to
manifolds. In particular, certain embodiments described herein are
directed to manifolds that can be used in a mass spectrometer.
BACKGROUND
[0002] In many analytical instruments, fluid flow is directed or
controlled during operation of the instrument. For example, in mass
spectrometers, the fluid flow can be controlled during operation of
the mass spectrometer.
SUMMARY
[0003] In one aspect, a vacuum manifold comprising a housing
comprising a first port configured to provide fluidic coupling
between a sampling interface line and the manifold is provided. In
some embodiments, the manifold also comprises a second port on the
housing that is configured to provide fluidic coupling between a
pump backing line, e.g., a turbomolecular pump backing line, and
the manifold. In other embodiments, the manifold also comprises a
third port on a housing that is configured to provide fluidic
coupling between a mechanical roughing pump and the manifold. In
certain embodiments, the manifold also comprises a moveable sealing
member in the vacuum manifold, e.g., an internal moveable sealing
member, in which the moveable sealing member comprises a first
position effective to permit fluid flow between the first port and
the third port and effective to block fluid flow from the second
port, in which the moveable sealing member comprises a second
position effective to permit fluid flow between the second port and
the third port and effective to block fluid flow from the first
port, in which the moveable sealing member further comprises a
third position effective to permit fluid flow between the first
port, the second port and the third port.
[0004] In certain examples, the moveable sealing member comprises a
sealing device configured to engage the second port in the first
position of the moveable sealing member to provide a substantially
fluid tight seal between the sealing member and the second port. In
other examples, the sealing device is configured to engage the
first port in the second position of the moveable sealing member to
provide a substantially fluid tight seal between the sealing member
and the first port. In some examples, the sealing device comprises
a first O-ring that is between the sealing device and the second
port when the sealing member is in the first position, and a second
O-ring that is between the sealing device and the first port when
the sealing member is in the second position. In some embodiments,
the manifold may include, or may be coupled to, an actuator coupled
to the moveable sealing member. In some examples, the actuator
comprises a motor. In other examples, the sealing member comprises
a plunger coupled to the actuator. In certain embodiments, the
plunger comprises a longitudinal shaft coupled to the actuator and
a disk coupled to the longitudinal shaft in an orthogonal direction
to the longitudinal shaft, the disk configured to engage an
interior manifold surface adjacent to the first port in the second
position of the moveable sealing member to provide a substantially
fluid tight seal between the plunger and the first port to block
fluid flow into the manifold from the sampling interface line, in
which the disk is further configured to engage an interior manifold
surface adjacent to the second port in the first position of the
moveable sealing member to provide a substantially fluid tight seal
between the plunger and the second port to block fluid flow into
the manifold from the pump backing line.
[0005] In other embodiments, the sealing member can include a
plunger comprising a first longitudinal shaft of a first outer
diameter coupled to the actuator and a second longitudinal shaft of
a second outer diameter, greater than the first outer diameter,
coupled to the first longitudinal shaft, in which an end of the
second longitudinal shaft is configured to engage an interior
manifold surface adjacent to the first port in the second position
of the moveable sealing member to provide a substantially fluid
tight seal between the plunger and the first port to block fluid
flow into the manifold from the sampling interface line, in which
an opposite end of the second longitudinal shaft is configured to
engage an interior manifold surface adjacent to the second port in
the first position of the moveable sealing member to provide a
substantially fluid tight seal between the plunger and the second
port to block fluid flow into the manifold from the pump backing
line. In some embodiments, the second outer diameter is selected to
be at least 5% greater than a diameter of the first port.
[0006] In other embodiments, the sealing member comprises a plunger
comprising a longitudinal shaft coupled to the actuator and a
barbell end coupled to the longitudinal shaft, in which a first
surface of the barbell end is configured to engage an interior
manifold surface adjacent to the first port in the second position
of the moveable sealing member to provide a substantially fluid
tight seal between the engaged first surface and the first port to
block fluid flow into the manifold from the sampling interface
line, in which a second surface of the barbell end is configured to
engage an interior manifold surface adjacent to the second port in
the first position of the moveable sealing member to provide a
substantially fluid tight seal between the engaged second surface
and the second port to block fluid flow into the manifold from the
backing line.
[0007] In some examples, the third position of the sealing member
is selected to position a terminal end of the sealing member closer
to the first port of manifold than to the second port of the
manifold. In other examples, the third position of the sealing
member is selected to provide a selected fluidic conductance. In
other embodiments, the sealing member comprises an actuator coupled
to a longitudinal shaft, and a disk coupled to the longitudinal
shaft in an orthogonal direction, in which the longitudinal shaft
comprises a bellows effective to provide a substantially fluid
tight seal between the housing and a site of the housing where the
longitudinal shaft of the sealing member enters the housing. In
some embodiments, the actuator comprises a motor. In other
embodiments, the second position of the sealing member is provided
after a fixed amount of steps using the motor. In certain
configurations, the sealing member comprises a substantially inert
material. In some embodiments, the substantially inert material is
a plastic, a stainless steel, polytetrafluoroethylene, aluminum,
titanium or an Inconel alloy.
[0008] In certain examples, the sealing member is configured for
use with an inductively coupled plasma mass spectrometer system, in
which the sealing member is configured to be in the first position
when a vacuum is off and the plasma is off, in which the sealing
member is configured to be in the second position when the vacuum
is on and when the plasma is off, and in which the sealing member
is configured to be in the third position when the plasma is on. In
some embodiments, the vacuum manifold is configured as a valveless
manifold.
[0009] In another aspect, a vacuum manifold comprising a first
inlet port and a second inlet port each configured to permit fluid
flow into the manifold, the manifold comprising an internal sealing
member configured to prevent fluid flow into the manifold from the
second port in a first position of the internal sealing member, the
internal sealing member further configured to prevent fluid flow
into the manifold from the first port in a second position of the
internal sealing member, and the internal sealing member further
configured to permit fluid flow into the manifold from both the
first port and the second port in a third position of the internal
sealing member is described. In some embodiments, the internal
sealing member is an internal moveable sealing member, e.g., one
where it may be translated or physically moved in one or more
directions.
[0010] In certain embodiments, the manifold can include an outlet
port configured to permit fluid flow out of the manifold. In other
embodiments, the outlet port is fluidically coupled to a vacuum
pump that is effective to increase fluid flow into the manifold
from the first port and from the second port when the internal
sealing member is in the third position. In some examples, the
internal sealing member is configured to be positioned closer to
the second port than the first port when the internal sealing
member is in the third position. In certain embodiments, the third
position of the internal sealing member is selected to provide a
selected fluidic conductance.
[0011] In certain examples, the internal sealing member comprises a
plunger coupled to a longitudinal shaft, in which the plunger is
sized and arranged to seal to a first internal surface of the
manifold in the first position of the sealing member to prevent
fluid flow into the manifold from the second port, and in which the
plunger is also sized and arranged to seal to a second internal
surface of the manifold in the second position of the sealing
member to prevent fluid flow into the manifold from the first port.
In some embodiments, the plunger comprises a disk coupled to the
longitudinal shaft. In certain examples, the plunger comprises a
barbell-shaped end coupled to the longitudinal shaft. In some
embodiments, the plunger comprises a second longitudinal shaft
coupled to the first longitudinal shaft, in which an outer diameter
of the second longitudinal shaft is greater than an outer diameter
of the first longitudinal shaft. In additional examples, the outer
diameter of the second longitudinal shaft is configured to be at
least 5% larger than a diameter of the first port. In some
examples, the plunger comprises a first O-ring configured to
provide a substantially fluid tight seal between the plunger and
the second port when the sealing member is in the first position.
In certain embodiments, the plunger comprises a second O-ring
configured to provide a substantially fluid tight seal between the
plunger and the first port when the sealing member is in the second
position. In other embodiments, the plunger comprises a first
O-ring configured to provide a substantially fluid tight seal
between the plunger and the first port when the sealing member is
in the second position. In some examples, the longitudinal shaft
can be coupled to an actuator effective to move the sealing member
between the first position, the second position and the third
position. In certain examples, the actuator comprises a ternary
device configured to move the sealing member sequentially between
the first position, the second position and the third position. In
some embodiments, the actuator comprises a motor. In certain
instances, the motor is a stepper motor. In certain embodiments,
the sealing member comprises a substantially inert material
comprising one or more of a plastic, a stainless steel,
polytetrafluoroethylene, aluminum, titanium or an Inconel alloy. In
some examples, the sealing member is configured for use with an
inductively coupled plasma mass spectrometer system, in which the
sealing member is configured to be in the first position when a
vacuum is off and the plasma is off, in which the sealing member is
configured to be in the second position when the vacuum is on and
when the plasma is off, and in which the sealing member is
configured to be in the third position when the plasma is on. In
some embodiments, the vacuum manifold is configured as a valveless
manifold.
[0012] In an additional aspect, a manifold comprising a first port
configured to provide fluidic coupling between a sampling interface
of the inductively coupled plasma mass spectrometer and a first
pump of an inductively coupled plasma mass spectrometer, and
comprising a second port configured to provide fluidic coupling
between a second pump of the inductively coupled plasma mass
spectrometer and the first pump, the manifold comprising an
internal sealing member configured to be positioned at a first
position in the manifold to block fluid flow between the first pump
and the second pump, the internal sealing member further configured
to be positioned at a second position in the manifold to block
fluid flow between the sampling interface and the first pump, and
the internal sealing member further configured to be positioned at
a third position in the manifold to permit fluid flow between the
sampling interface and the first pump and to permit fluid flow
between the second pump and the first pump is disclosed. In certain
embodiments, the internal sealing member can be configured to by
translated or physically displaced as it is positioned at the
different positions.
[0013] In certain embodiments, the first pump is configured as a
mechanical roughing pump. In some embodiments, the second pump is
configured as a turbomolecular pump. In other embodiments, the
manifold comprises an outlet port that is fluidically coupled to
the first pump and is effective to increase fluid flow into the
manifold from the first port and from the second port when the
internal sealing member is in the third position. In some examples,
the internal sealing member is configured to be positioned closer
to the second port than the first port when the internal sealing
member is in the third position. In other embodiments, the third
position of the internal sealing member is selected to provide a
selected fluidic conductance. In certain examples, the internal
sealing member comprises a plunger coupled to a longitudinal shaft,
in which the plunger is sized and arranged to seal to a first
internal surface of the manifold in the first position of the
sealing member to prevent fluid flow into the manifold from the
second port, and in which the plunger is also sized and arranged to
seal to a second internal surface of the manifold in the second
position of the sealing member to prevent fluid flow into the
manifold from the first port. In some embodiments, the plunger
comprises an orthogonal disk coupled to the longitudinal shaft. In
certain instances, the plunger comprises a barbell-shaped end
coupled to the longitudinal shaft. In other instances, the plunger
comprises a second longitudinal shaft coupled to the first
longitudinal shaft, in which an outer diameter of the second
longitudinal shaft is greater than an outer diameter of the first
longitudinal shaft. In certain examples, the outer diameter of the
second longitudinal shaft is configured to be at least 5% larger
than a diameter of the first port. In other embodiments, the
plunger comprises a first O-ring configured to provide a
substantially fluid tight seal between the plunger and the second
port when the sealing member is in the first position. In some
embodiments, the plunger comprises a second O-ring configured to
provide a substantially fluid tight seal between the plunger and
the first port when the sealing member is in the second position.
In additional embodiments, the plunger comprises a first O-ring
configured to provide a substantially fluid tight seal between the
plunger and the first port when the sealing member is in the second
position.
[0014] In certain examples, the longitudinal shaft is coupled to an
actuator effective to move the sealing member between the first
position, the second position and the third position. In certain
embodiments, the actuator comprises a ternary device configured to
move the sealing member sequentially between the first position,
the second position and the third position. In some examples, the
actuator comprises a motor. In other examples, the motor is a
stepper motor. In some embodiments, the internal sealing member
comprises a substantially inert material comprising one or more of
a plastic, a stainless steel, polytetrafluoroethylene, aluminum,
titanium or an Inconel alloy. In additional embodiments, the
sealing member is configured to be in the first position when a
vacuum is off and the plasma is off, in which the sealing member is
configured to be in the second position when the vacuum is on and
when the plasma is off, and in which the sealing member is
configured to be in the third position when the plasma is on. In
further embodiments, the vacuum manifold is configured as a
valveless manifold.
[0015] In another aspect, a system comprising a manifold comprising
a first inlet port, a second inlet port and an outlet port is
provided. In some embodiments, the system can include a first pump
fluidically coupled to the outlet port, a second pump fluidically
coupled to the first inlet port, and a sampling interface
fluidically coupled to the second inlet port. In some embodiments,
the manifold further comprises an internal sealing member
configured to be positioned at a first position in the manifold to
block fluid flow between the first pump and the second pump, the
internal sealing member further configured to be positioned at a
second position in the manifold to block fluid flow between the
sampling interface and the first pump, and the internal sealing
member further configured to be positioned at a third position in
the manifold to permit fluid flow between the sampling interface
and the first pump and to permit fluid flow between the second pump
and the first pump.
[0016] In certain examples, the system can also include an
inductively coupled plasma torch configured to fluidically couple
to the sampling interface. In other embodiments, the system can
include at least one induction device configured to sustain an
inductively coupled plasma in the inductively coupled plasma torch.
In some embodiments, the induction device is configured as a
helical induction coil. In other embodiments, the induction device
is configured as at least one flat plate electrode. In further
embodiments, the first pump is a mechanical roughing pump and the
second pump is a turbomolecular pump. In some instances, the system
can include a mass analyzer fluidically coupled to the sampling
interface. In other instances, the system can include a detector
fluidically coupled to the mass analyzer. In certain embodiments,
the system can include a sample introduction system fluidically
coupled to the inductively coupled plasma torch. In certain
embodiments, the system can include at least one ion lens
fluidically coupled to the sampling interface. In other
embodiments, the system can include a collision/reaction cell.
[0017] In certain embodiments, the internal sealing member of the
system comprises a plunger coupled to a longitudinal shaft, in
which the plunger is sized and arranged to seal to a first internal
surface of the manifold in the first position of the sealing member
to prevent fluid flow into the manifold from the second pump, and
in which the plunger is also sized and arranged to seal to a second
internal surface of the manifold in the second position of the
sealing member to prevent fluid flow into the manifold from the
sampling interface. In some instances, the plunger comprises an
orthogonal disk coupled to the longitudinal shaft. In certain
embodiments, the plunger comprises a barbell-shaped end coupled to
the longitudinal shaft. In other embodiments, the plunger comprises
a second longitudinal shaft coupled to the first longitudinal
shaft, in which an outer diameter of the second longitudinal shaft
is greater than an outer diameter of the first longitudinal shaft.
In further embodiments, the outer diameter of the second
longitudinal shaft is configured to be at least 5% larger than a
diameter of the first port. In additional embodiments, the plunger
comprises a first O-ring configured to provide a substantially
fluid tight seal between the plunger and the second port when the
sealing member is in the first position. In some embodiments, the
plunger comprises a second O-ring configured to provide a
substantially fluid tight seal between the plunger and the first
port when the sealing member is in the second position. In certain
examples, the plunger comprises a first O-ring configured to
provide a substantially fluid tight seal between the plunger and
the first port when the sealing member is in the second position.
In other embodiments, the longitudinal shaft is coupled to an
actuator effective to move the sealing member between the first
position, the second position and the third position. In certain
embodiments, the actuator comprises a ternary device configured to
move the sealing member sequentially between the first position,
the second position and the third position. In other embodiments,
the actuator comprises a motor, e.g., a stepper motor. In some
embodiments, the internal sealing member comprises a substantially
inert material comprising one or more of a plastic, a stainless
steel, polytetrafluoroethylene, aluminum, titanium or an Inconel
alloy. In other embodiments, the sealing member is configured to be
in the first position when a vacuum is off and the plasma is off,
in which the sealing member is configured to be in the second
position when the vacuum is on and when the plasma is off, and in
which the sealing member is configured to be in the third position
when the plasma is on.
[0018] In an additional aspect, a system comprising an
atomization/ionization device configured to sustain an ionization
source, an induction device configured to provide energy to the
ionization device to sustain the ionization source in the
ionization device, a manifold comprising a first inlet port, a
second inlet port and an outlet port, a first pump fluidically
coupled to the outlet port, a second pump fluidically coupled to
the first inlet port, a sampling interface fluidically coupled to
the second inlet port and to the ionization device, in which the
manifold further comprises an internal sealing member configured to
be positioned at a first position in the manifold to block fluid
flow between the first pump and the second pump, the internal
sealing member further configured to be positioned at a second
position in the manifold to block fluid flow between the sampling
interface and the first pump, and the internal sealing member
further configured to be positioned at a third position in the
manifold to permit fluid flow between the sampling interface and
the first pump and to permit fluid flow between the second pump and
the first pump is provided.
[0019] In certain embodiments, the ionization device is an
inductively coupled plasma. In other embodiments, the induction
device comprises a helical induction coil. In other examples, the
induction device comprises at least one flat plate electrode. In
certain embodiments, the first pump is a mechanical roughing pump
and the second pump is a turbomolecular pump. In certain
embodiments, the system can include a mass analyzer fluidically
coupled to the sampling interface. In certain embodiments, the
system can include a detector fluidically coupled to the mass
analyzer. In other embodiments, the system can include a sample
introduction system fluidically coupled to the ionization device.
In some examples, the system can include at least one ion lens
fluidically coupled to the sampling interface. In additional
examples, the system can include a collision/reaction cell.
[0020] In certain examples, the internal sealing member of the
system comprises a plunger coupled to a longitudinal shaft, in
which the plunger is sized and arranged to seal to a first internal
surface of the manifold in the first position of the sealing member
to prevent fluid flow into the manifold from the second pump, and
in which the plunger is also sized and arranged to seal to a second
internal surface of the manifold in the second position of the
sealing member to prevent fluid flow into the manifold from the
sampling interface. In some embodiments, the plunger comprises an
orthogonal disk coupled to the longitudinal shaft. In other
embodiments, the plunger comprises a barbell-shaped end coupled to
the longitudinal shaft. In certain examples, the plunger comprises
a second longitudinal shaft coupled to the first longitudinal
shaft, in which an outer diameter of the second longitudinal shaft
is greater than an outer diameter of the first longitudinal shaft.
In further examples, the outer diameter of the second longitudinal
shaft is configured to be at least 5% larger than a diameter of the
first port. In additional examples, the plunger comprises a first
O-ring configured to provide a substantially fluid tight seal
between the plunger and the second port when the sealing member is
in the first position. In some embodiments, the plunger comprises a
second O-ring configured to provide a substantially fluid tight
seal between the plunger and the first port when the sealing member
is in the second position. In additional embodiments, the plunger
comprises a first O-ring configured to provide a substantially
fluid tight seal between the plunger and the first port when the
sealing member is in the second position. In some examples, the
longitudinal shaft is coupled to an actuator effective to move the
sealing member between the first position, the second position and
the third position. In further embodiments, the actuator comprises
a ternary device configured to move the sealing member sequentially
between the first position, the second position and the third
position. In some instances, the actuator comprises a motor, e.g.,
a stepper motor. In some embodiments, the internal sealing member
of the system comprises a substantially inert material comprising
one or more of a plastic, a stainless steel,
polytetrafluoroethylene, aluminum, titanium or an Inconel alloy. In
certain embodiments, the sealing member is configured to be in the
first position when a vacuum is off and the plasma is off, in which
the sealing member is configured to be in the second position when
the vacuum is on and when the plasma is off, and in which the
sealing member is configured to be in the third position when the
plasma is on. In other embodiments, the manifold is configured as a
valveless manifold.
[0021] In another aspect, a method of analyzing species using a
mass spectrometer, the method comprising actuating an internal
sealing member of a manifold between a first position, a second
position and a third position, the first position effective to
block fluid flow from a pump backing line into the manifold, the
second position effective to block fluid flow from a sampling
interface into the manifold, and the third position effective to
permit fluid flow between the pump backing line and a roughing pump
and between the sampling interface line and the roughing pump is
provided.
[0022] In certain embodiments, the method comprises engaging a
sealing device of the sealing member to an internal surface of the
manifold to block fluid flow from the pump backing line into the
manifold in the first position of the sealing member. In some
embodiments, the method comprises engaging a sealing device of the
sealing member to an internal surface of the manifold to block
fluid flow from the sampling interface into the manifold in the
second position of the sealing member. In certain examples, the
method comprises positioning a sealing device of the internal
sealing member to be closer to the second port in the third
position of the sealing member. In other examples, the method
comprises initiating a vacuum when the sealing member is in the
second position. In further examples, the method comprises igniting
an ionization source when the sealing member is in the second
position. In additional examples, the method comprises actuating
the sealing member from the second position to the third position
after the ionization source is ignited.
[0023] In certain embodiments the method comprises configuring the
sealing member with a longitudinal shaft coupled to a plunger. In
some embodiments, the plunger comprises a single head or a double
head. In other embodiments, the method comprises configuring the
manifold to be a valveless manifold.
[0024] In another aspect, a method of operating an inductively
coupled plasma mass spectrometer comprising actuating an internal
sealing member of a vacuum manifold between a first position,
effective to block fluid flow from a pump backing line into the
manifold, to a second position, effective to permit fluid flow from
the pump backing line into the manifold when a vacuum is initiated
in the inductively coupled plasma mass spectrometer, and actuating
the internal sealing member to a third position to permit fluid
flow into the manifold from the pump backing line and to permit
fluid flow into the manifold from a sampling interface line when
the vacuum is present and when the plasma is sustained is
described.
[0025] In certain embodiments, the method comprises engaging a
sealing device of the sealing member to an internal surface of the
manifold to block fluid flow from the pump backing line into the
manifold in the first position of the sealing member. In some
embodiments, the method comprises engaging a sealing device of the
sealing member to an internal surface of the manifold to block
fluid flow from the sampling interface into the manifold in the
second position of the sealing member. In additional examples, the
method comprises positioning a sealing device of the internal
sealing member to be closer to the second port in the third
position of the sealing member. In other embodiments, the method
comprises actuating the internal sealing member using a motor. In
further embodiments, the method comprises configuring the sealing
member with a longitudinal shaft coupled to a plunger at one end
and coupled to the motor at an opposite end. In certain examples,
the method includes configuring the plunger with a single head or
with a double head. In certain embodiments, the method includes
configuring the plunger as a longitudinal shaft comprising an outer
diameter greater than an outer diameter of the longitudinal shaft.
In some embodiments, the method includes configuring the manifold
to be a valveless manifold.
[0026] In another aspect, a method of operating an inductively
coupled plasma spectrometer, the method comprising providing a
vacuum manifold comprising a first inlet port and a second inlet
port each configured to permit fluid flow into the manifold, the
manifold comprising an internal sealing member configured to
prevent fluid flow into the manifold from the second port in a
first position of the internal sealing member, the internal sealing
member further configured to prevent fluid flow into the manifold
from the first port in a second position of the internal sealing
member, and the internal sealing member further configured to
permit fluid flow into the manifold from both the first port and
the second port in a third position of the internal sealing member
is provided.
[0027] In an additional aspect, a method of operating an
inductively coupled plasma spectrometer, the method comprising
providing a vacuum manifold comprising a housing comprising a first
port configured to provide fluidic coupling between a sampling
interface line and the manifold; a second port on the housing that
is configured to provide fluidic coupling between a pump backing
line and the manifold; a third port on a housing that is configured
to provide fluidic coupling between a mechanical roughing pump and
the manifold; and a moveable sealing member in the vacuum manifold,
in which the moveable sealing member comprises a first position
effective to permit fluid flow between the first port and the third
port and effective to block fluid flow from the second port, in
which the moveable sealing member comprises a second position
effective to permit fluid flow between the second port and the
third port and effective to block fluid flow from the first port,
in which the moveable sealing member further comprises a third
position effective to permit fluid flow between the first port, the
second port and the third port is described.
[0028] In another aspect, a method of operating an inductively
coupled plasma spectrometer, the method comprising providing a
manifold comprising a first port configured to provide fluidic
coupling between a sampling interface of the inductively coupled
plasma mass spectrometer and a first pump of an inductively coupled
plasma mass spectrometer, and comprising a second port configured
to provide fluidic coupling between a second pump of the
inductively coupled plasma mass spectrometer and the first pump,
the manifold comprising an internal sealing member configured to be
positioned at a first position in the manifold to block fluid flow
between the first pump and the second pump, the internal sealing
member further configured to be positioned at a second position in
the manifold to block fluid flow between the sampling interface and
the first pump, and the internal sealing member further configured
to be positioned at a third position in the manifold to permit
fluid flow between the sampling interface and the first pump and to
permit fluid flow between the second pump and the first pump is
disclosed.
[0029] In an additional aspect, a method of operating an
inductively coupled plasma spectrometer, the method comprising
providing a system comprising a manifold comprising a first inlet
port, a second inlet port and an outlet port; a first pump
fluidically coupled to the outlet port; a second pump fluidically
coupled to the first inlet port, a sampling interface fluidically
coupled to the second inlet port, in which the manifold further
comprises an internal sealing member configured to be positioned at
a first position in the manifold to block fluid flow between the
first pump and the second pump, the internal sealing member further
configured to be positioned at a second position in the manifold to
block fluid flow between the sampling interface and the first pump,
and the internal sealing member further configured to be positioned
at a third position in the manifold to permit fluid flow between
the sampling interface and the first pump and to permit fluid flow
between the second pump and the first pump.
[0030] In another aspect, a method of operating an inductively
coupled plasma spectrometer, the method comprising providing a
system comprising an ionization device configured to sustain an
ionization source, an induction device configured to provide energy
to the ionization device to sustain the ionization source in the
ionization device, a manifold comprising a first inlet port, a
second inlet port and an outlet port; a first pump fluidically
coupled to the outlet port, a second pump fluidically coupled to
the first inlet port; a sampling interface fluidically coupled to
the second inlet port and to the ionization device, in which the
manifold further comprises an internal sealing member configured to
be positioned at a first position in the manifold to block fluid
flow between the first pump and the second pump, the internal
sealing member further configured to be positioned at a second
position in the manifold to block fluid flow between the sampling
interface and the first pump, and the internal sealing member
further configured to be positioned at a third position in the
manifold to permit fluid flow between the sampling interface and
the first pump and to permit fluid flow between the second pump and
the first pump is provided.
[0031] In an additional aspect, a method of operating an
inductively coupled plasma mass spectrometer comprising is
provided. In certain examples, the method comprises actuating an
internal sealing member of a vacuum manifold between a first
position effective to block fluid flow from a pump backing line
into the manifold to a second position effective to permit fluid
flow from the pump backing line into the manifold and effective to
block fluid flow from an interface line into the manifold, reducing
the pressure in the mass spectrometer using at least one pump,
igniting an ionization source, e.g., an inductively coupled plasma,
actuating the internal sealing member away from the second position
to provide a fluid leak that permits fluid from the interface line
to flow into the vacuum manifold, monitoring current draw of a
turbomolecular pump of the mass spectrometer, and actuating the
internal sealing member from the second position toward a final
position after the current draw of the turbomolecular pump
stabilizes.
[0032] In certain embodiments, the method can include stopping
actuation of the internal sealing member away from the second
position if the monitored current draw of the turbomolecular pump
exceeds a current limit. In some embodiments, the method can
include reinitiating actuation of the internal sealing member
toward the final position once the monitored current draw is below
the current limit.
[0033] In another aspect, a kit comprising one or more of the
manifolds described herein, optionally with a software program,
electrical harness, actuator or other components desired to permit
operation of the manifold in a mass spectrometer system are also
provided.
[0034] Additional aspects, embodiments, configurations, features
and attributes of the manifolds are described herein.
BRIEF DESCRIPTION OF THE FIGURES
[0035] Certain figures are described below to illustrate further
some of the attributes of the technology described herein, in
which:
[0036] FIGS. 1A-1C are illustrations of a manifold comprising two
ports and an internal sealing member, in accordance with certain
examples;
[0037] FIG. 2A is an illustration of a manifold comprising a
dumbbell shape, in accordance with certain examples;
[0038] FIG. 2B is an illustration of a manifold comprising a
double-headed plunger, in accordance with certain examples;
[0039] FIGS. 3A and 3B are illustrations of manifolds comprising
offset ports, in accordance with certain examples;
[0040] FIGS. 4A-4C are illustration of a manifold comprising three
ports and an internal sealing member, in accordance with certain
examples;
[0041] FIG. 5 is an illustration of a manifold comprising four
ports, in accordance with certain examples;
[0042] FIGS. 6A and 6B are illustrations of a manifold comprising a
sealing member that can block two ports, in accordance with certain
examples;
[0043] FIGS. 7A-7D are illustrations showing a three port manifold,
in accordance with certain examples;
[0044] FIG. 8 is a block diagram of some components in a mass
spectrometer, in accordance with certain examples;
[0045] FIGS. 9A-9C are illustrations of a manifold configured for
use in a mass spectrometer, in accordance with certain
examples;
[0046] FIG. 10 is a perspective view of a manifold and a motor, in
accordance with certain examples; and
[0047] FIG. 11 is a cross-section of a manifold comprising an
internal sealing member, in accordance with certain examples.
[0048] It will be recognized by the person of ordinary skill in the
art, given the benefit of this disclosure, that certain elements in
the figures may be shown in an enlarged, distorted or
disproportionate manner to facilitate a better understanding of
certain embodiments and configurations. Unless otherwise specified
in the description, no particular size, dimensions, materials or
shapes are intended to be required.
DETAILED DESCRIPTION
[0049] Certain embodiments described herein can permit fluid flow
through a system in a desired manner. In certain configurations,
the manifolds described herein can be configured to permit fluid
flow between two or more ports of the manifold. While certain
configurations are described herein as permitting fluid flow
between two or more ports, the fluidic conductance in the manifold
may vary depending on the overall configuration of the system and
the exact position or configuration of the manifold in the system.
In some embodiments, the sealing members described herein are
described as including separate portions or components for ease of
description. It will be recognized by the person of ordinary skill
in the art, given the benefit of this disclosure, that the sealing
member may generally be considered an integral device with no
defined separation or demarcation between the heads or ends and the
connecting members. Where the sealing member is described as being
moved or moveable, the sealing member may be translated or
physically displaced in one or more dimensions to seal off a
desired port or ports in the manifold or permit fluid flow into the
manifold through selected ports.
[0050] In certain examples, the manifolds described herein can
include two or more ports that can be used to provide fluidic
coupling between other components in a system. For example, where a
first fluid line is coupled to a first port on the manifold, the
manifold may permit fluid flow between the first port and a second
fluid line that is fluidically coupled to a second port on the
manifold. In some configuration, fluid flow from the first fluid
line can be stopped by adjusting a position of a sealing member in
the manifold. For example, a sealing member within the manifold can
be moved to an effective position to prevent fluid flow from the
first fluid line from being provided to the second fluid line. In
instances where such fluid flow is halted, the sealing member may
halt fluid flow within the manifold such that some portion of fluid
from the first fluid line enters the manifold, but such fluid is
not provided to the second fluid line through the second port.
Referring to FIG. 1A, an illustration of a manifold 100 comprising
a first port 110, a second port 120 and an internal sealing member
130 is shown. The exact distance between the ports of the manifolds
described herein may vary. For example, from the port 110 to the
port 120, the total distance may be about 5 mm to about 30 mm, for
example, about 10 mm to about 20 mm, e.g., about 12, 13, 14 or 15
mm. While the ports 110 and 120 (and other ports described herein)
are shown as projecting outward from the manifold 100 for ease of
reference, the ports are generally flush with the surface of the
manifold 100, and a fluid line can couple to the port to permit
fluid flow from the coupled fluid line into the manifold 100. The
sealing member 130 includes a first portion or head 135 within the
interior of the manifold 100 and a second portion 140 that
protrudes through the manifold 100. When the head 135 of the
sealing member 130 is placed adjacent to the first port 110 and
contacts an inner surface 105 of the manifold 100, a substantially
fluid tight seal is provided between the surface 132 of the sealing
member head 135 and the surface 105 of the manifold 100 such that
no fluid flows into the manifold from the port 110. This
configuration stops fluid flow between the ports 110 and 120. While
not shown, the surface 136 of the head 135 of the internal sealing
member 130 can include a gasket, a membrane, an elastomer or a film
that is forced into contact with the surface 105 to enhance the
substantially fluid tight seal between the surfaces 105 and
136.
[0051] In certain embodiments, the second portion 140 of the
sealing member 130 can be configured as a longitudinal shaft or rod
that can be coupled to a motor or actuator that is effective to
displace or translate the sealing member 130 from one position to
another by rotation of the longitudinal shaft. Referring to FIG.
1B, the sealing member 130 has been moved to provide a seal between
a surface 137 of the sealing member head 135 and a surface 107 of
the manifold 100. Fluid flow from the first port 110 is not
provided to the port 120 as the surface 136 of the sealing member
prevents fluid in the manifold 100 from flowing into the port 120.
This configuration also stops fluid flow between the ports 110 and
120. In the configuration shown in FIG. 1B, fluid from the first
port 110 may flow into internal space within the manifold 100 but
does not exit the manifold 100 through the port 120. While not
shown, the surface 137 of the head 135 of the internal sealing
member 130 can include a gasket, a membrane, an elastomer or a film
that is forced into contact with the surface 107 to enhance the
substantially fluid tight seal between the surfaces 107 and
137.
[0052] In certain examples and referring to FIG. 1C, a position of
the sealing member 130 is shown that permits fluid flow between the
ports 110 and 120. The head 135 of the sealing member 130 is shown
as being positioned away from the surfaces 105 and 107 of the
manifold 100. Fluid may enter the manifold 100 through the port 110
and can flow out of the manifold 100 through the port 120.
Depending on the selected position of the sealing member 130, the
fluidic conductance within the manifold 100 may vary. For example,
the sealing member 130 can be positioned closer to the first port
110 or the second port 120 to alter the overall fluidic conductance
within the manifold. For example, a fluidic conductance of about
10-15 L/S may be suitable, e.g., about 13 L/S may be used. In some
embodiments, the head 135 of the internal sealing member 130 can be
positioned closer to the port 110, whereas in other examples, the
head 135 of the manifold 130 can be positioned closer to the port
120.
[0053] In certain configurations, the internal sealing member 120
can be coupled to a stepper motor or actuator through portion 140
that can be used to adjust the position of the head 135 between
those shown in FIGS. 1A and 1B. For example, a stepper motor (not
shown) can be moved a known number of steps to move the head 135
from the position shown in FIG. 1A to the position shown in FIG.
1B. When the desired number of steps has been performed, the seal
between surfaces 107 and 137 should be provided. To move the head
135 to the position shown in FIG. 1C, the stepper motor may move
the head 135 back a selected number of steps to permit a desired
fluid flow through the manifold 100. In some embodiments of the
manifolds described herein, the final position of the head 135 can
be user-selected or user-adjustable to provide desired fluid flow
characteristics within the manifold 100. In other embodiments, the
positions of the head 135 can be programmed into a processor or
memory unit (or hard coded into firmware) such that the positions
and steps implemented are determined by the firmware and are not
generally user adjustable. If desired, the motor or actuator can be
a binary device with three defined stop positions to position the
sealing member 135 at two positions including a first position
adjacent to the port 110, and a second position adjacent to the
port 120.
[0054] In certain embodiments, the manifold 100 can be configured
as a valveless manifold where no mechanical valves, e.g., solenoid
valves, are present or used to control fluid flow into or within
the manifold. In contrast to manifolds with mechanical valves,
manifolds using the internal sealing members described herein can
be produced at reduced cost, can have longer usable lifetimes and
require fewer controls. If desired, valves can be included on or in
one or more ports of the manifold to provide for further control of
fluid flow in the system.
[0055] In certain embodiments, the exact dimensions of the ports
110 and 120 may vary, and in certain embodiments, the ports may be
sized substantially the same whereas in other embodiments the ports
may be sized differently. Where the ports are sized differently,
the final position of the head 135 may be adjusted to provide a
similar fluid flow through the manifold compared to the flow that
results where the ports 110 and 120 are substantially the same size
and dimensions. In some embodiments, the ports 110 and 120 may
independently each be about 5 mm to about 50 mm, more particularly
about 10 mm to about 40 mm, for example, about 15 mm to about 40
mm.
[0056] In some configurations, the exact shapes and dimensions of
the head 135 of the sealing member 130 may vary. For example, the
shape and length of the head 135 may vary depending on the number
of ports in the manifold 100, the desired fluid flow within the
manifold 100, the overall form factor of the manifold 100 or other
desired features. In some embodiments, the head 135 generally takes
the form of a cylinder whose cross-sectional diameter is larger
than the cross-sectional diameter of a port that the head 135 is
intended to seal. For example, the cross-sectional diameter of the
surface 136 of the head 135 may be an effective diameter to provide
the substantially fluid tight seal when the surface 136 is engaged
to the surface 105 or when the surface 137 is engaged to the
surface 107. In some embodiments, the cross-sectional diameter of
the head 135 may be about 5% larger than the cross-sectional
diameter than the larger of the ports 110 and 120. In other
embodiments, the cross-sectional diameter can be about 10% larger
than the larger cross-sectional diameter of the ports 110 and
120.
[0057] In some instances, the sealing member may take the shape of
a dumbbell 210 as shown in FIG. 2A. The dumbbell shape is generally
characterized as including terminal portions that had a larger
diameter than a middle connecting portion. The terminal portions
can be sized and arranged to provide a substantially fluid tight
seal when the terminal portions engage the internal surfaces of the
manifold. If desired the terminal portions may each be disk shaped
as shown in FIG. 2A, or the edges of the terminal portions can be
rounded or curved to facilitate better fluid flow within the
manifold 200.
[0058] In certain configurations, the sealing member can comprise a
double-headed plunger shape with a connecting portion having a
smaller diameter than terminal portions. Referring to FIG. 2B, a
double-headed plunger shape 260 is shown in a manifold 250. The
double-headed plunger comprises terminal portions or plunger heads
262 and 264 which have a larger diameter than a connecting portion
266. Surfaces of the terminal portions 262 and 264 can seal to the
ports of the manifold 250 to prohibit fluid flow between the two
ports. If desired, the terminal portions 262 and 264 can be concave
in shape such that an outer rim or ring of the plunger heads are
effective to engage the inner surface of the manifold to seal off
one of the ports.
[0059] In some instances, the sealing members described herein may
generally be solid bodies without any void space within them. In
other instances, the sealing members can be hollow or have open
space within them to reduce their weight or reduce overall cost of
manufacturing the sealing member. If desired, one or more areas or
portions of the sealing member can be weighted, angled, tipped or
otherwise configured in some desired manner.
[0060] In certain embodiments, the sealing member can comprise a
generally inert material that will not react or interfere with the
fluid or species in the fluid that flow through the manifold. In
some embodiments, the sealing member can comprise one or more of a
plastic, a stainless steel, polytetrafluoroethylene, an aluminum,
titanium, an Inconel alloy, passivated aluminum, a
perfluoroelastomer, a refractory material (e.g., alumina), an inert
elastomer or rubber material (e.g., Viton.RTM. fluoroelastomer) or
other similar materials. In some embodiments, the sealing member
can include a body produced from one material and a covering or
coating of another material. For example, the sealing member body
can be produced from a steel or non-inert plastic, which can be
covered or coated with a perfluoroelastomer to provide inertness to
the sealing member.
[0061] In certain embodiments, the ports of the manifolds described
herein need not be in the same plane of the manifold. Referring to
FIG. 3A, an illustration of a manifold 300 is shown where a first
port 310 is offset from a second port 320. The manifold 300
comprises a sealing member 330 with a first head 335 configured to
seal or mate to the first port 310, and a second head 340 offset
from the first head 335 and configured to mate or seal to the
second port 320. If desired the heads 335 and 340 can be large
enough so they are not offset from each other but are large enough
to seal to the ports 310 and 320 depending on the position of the
sealing member 330. For example, a sealing member 360 is shown in
the manifold 350 of FIG. 3B that has heads sized and arranged to
seal to ports 310 and 320 depending on the position of the sealing
member 360.
[0062] In certain examples, the manifolds described herein can be
used to permit fluid flow, or stop fluid flow, between more than
two fluid flow lines in a system. One configuration of a three port
manifold is shown in FIG. 4A that can be used to control fluid flow
between three different fluid lines. The manifold 400 comprises a
first port 410, a second port 420, and a third port 430. An
internal sealing member 440 comprises a first head 442, a second
head 444, and a connecting portion 446. The sealing member 440
comprises a connecting rod 450 that can be coupled to a motor or
actuator configured to move the sealing member 440 within the
manifold 400. If desired, the motor or actuator can be configured
as a ternary device with three pre-determined stop positions
including a first position to place the sealing member 440 adjacent
to the port 410, a second position to place the sealing member
adjacent to the port 420 and a third position to place the sealing
member between the first port 410 and the second port 420. As shown
in FIG. 4A, the sealing member 440 is engaged to the surface of the
port 410 to prevent fluid flow from the fluid line coupled to the
port 410 into the manifold 400. In the position of the sealing
member 440 shown in FIG. 4A, fluid may be permitted to flow between
the ports 420 and 430.
[0063] In some embodiments and referring to FIG. 4B, the position
of the sealing member 440 can be adjusted such that the head 444 is
engaged to the port 420. In this position, fluid is prevented from
flowing into the manifold 400 from the port 420 or flowing out of
the manifold 400 through the port 420. Fluid can flow between the
ports 410 and 430. Referring now to FIG. 4C, the sealing member 430
has been moved from the position that engages the second port 420
to a position within the manifold 400. Fluid may now flow between
the three ports 410, 420 and 430 of the manifold 400. Without
wishing to be bound by any particular theory, fluid may generally
flow down its pressure gradient with fluid flowing from higher
pressure toward lower pressure. Thus, depending on the pressure in
each of the fluid lines, fluid may flow from one or more of the
ports 410, 420 and 430 to one or more other ports 410, 420, 430.
Examples of manifolds including three ports and used and with three
different fluid flow lines are described in more detail below.
[0064] In certain embodiments and referring to FIG. 5, a manifold
500 comprising a first port 510, a second port 520, a third port
530 and a fourth port 540 is shown. The manifold 500 includes an
internal sealing member 550 including a first head 552, a second
head 554 and a connecting portion 556. The sealing member 550 is
coupled to a rod or shaft 560 which can be coupled to a motor or
actuator that can move the sealing member 550 within the manifold
500. The position shown in FIG. 5 permits fluid flow between all of
the ports 510, 520, 530 and 540. In some configurations, the
sealing member 550 can be engaged to the port 510 such that fluid
only flows between ports 520, 530 and 540. In other instances, the
sealing member 550 can be engaged to the port 520 such that fluid
only flows between ports 510, 530 and 540. Depending on the
position 550 of the sealing member, the fluidic conductance at each
of the ports 510, 520, 530 and 540 may vary.
[0065] In certain embodiments, the internal sealing member can be
configured such that fluid flow between fewer than three ports may
occur in a manifold comprising four or more ports. Referring to
FIG. 6, a manifold 600 is shown that comprises a first port 610, a
second port 620, a third port 630 and a fourth port 640 is shown.
The manifold 600 includes an internal sealing member 650 including
a first head 652, a second head 654 and a connecting portion 656.
The sealing member 650 is coupled to a rod or shaft 660 which can
be coupled to a motor or actuator that can move the sealing member
650 within the manifold 600. The position shown in FIG. 6A permits
fluid flow between all of the ports 610, 620, 630 and 640. In some
configurations, the sealing member 650 can be moved to engage the
ports 610 and 640 to prevent fluid flow into the manifold 600 as
shown in FIG. 6B. The head 654 is sized and arranged such that it
glides along the interior surface of the manifold 600 and blocks
the port 640 when the head 652 blocks the port 610. In this
configuration, fluid may be permitted to flow between the ports 620
and 630, but fluid does not flow into the manifold from the ports
610 or 640. A similarly configured sealing member as sealing member
650 may be used in connection with three ports manifold, five port
manifolds or manifold including more than five ports. In addition,
other configurations, e.g., where the sealing member is configured
to block ports across from each other, can also be used to provide
desired fluid flow into or out of the manifold.
[0066] In certain embodiments, the exact positioning and control of
the sealing member may vary depending on the system where the
manifold is present. If the pressures in different fluid lines that
couple to different ports vary substantially, then it may be
desirable to move or remove one head of the sealing member slowly
from a particular port. Referring to FIG. 7A, a manifold 700
comprises ports 710, 720 and 730 coupled to fluid flow lines 715,
725 and 735, respectively. The manifold 700 comprises a sealing
member 740 comprising a first head 742, second head 744 and
connecting member 746. As shown in FIG. 7A, the head 742 of the
sealing member 740 sits adjacent to the port 710 to prevent fluid
from flowing into the manifold 700 through the port 710. Where the
pressure in the fluid line 710 is substantially greater than the
pressure inside the manifold 700 or within the lines 725, 735, it
may be desirable to move the sealing member 740 gradually away from
the port 710 to permit fluid flow into the manifold 700. For
example, rapid movement of the sealing member 740 away from the
port 710 may result in rapid flow of fluid into the manifold 700.
Such rapid flow may not be desired in some instances as that could
lead to undesirable pressure fluctuations. To reduce the flow into
the manifold 700, the sealing member 740 can be moved slightly away
from the port 710, e.g., 1-5 steps using a stepper motor, to permit
leaking of fluid into the manifold 700 from the port 710 as shown
in FIG. 7B around the head 742 of the sealing member 740. After a
desired period, the sealing member 740 can be moved incrementally
further away from the port 710 to permit additional fluid to flow
into the manifold 700, as shown in FIG. 7C.
[0067] In certain embodiments, the resting or end position of the
sealing member 740 depends on the selected fluidic conductance for
the various ports of the manifold. If desired, the sealing member
can be positioned to balance the fluid load at the ports or to
account for different fluid loads through the ports. By positioning
the sealing member at a desired position, the cross-sectional area
of a particular fluid path through a port can be reduced (where the
sealing member is closer to the port) or can be increased (where
the sealing member is further away from the port).
[0068] In some embodiment, the final position of the sealing member
where all ports are open may be determined based on the number of
steps undertaken by a stepper motor. For example, the position
shown in FIG. 7A may be arbitrarily considered the zero position of
the stepper motor. To provide the leaking shown in FIG. 7B, the
motor can move about 1-5 steps. The final position of the motor may
be determined by the number of steps from the position shown in
FIG. 7B, e.g., 500 additional steps may be used to position the
sealing member at its final position. In certain embodiments, the
number of steps the motor is actuated can be used to determine when
a port is sealed to the sealing member. For example and referring
again to FIG. 7A, the position of the sealing member 740 sealed to
the port 710 can be considered the zero position. The motor can be
actuated a fixed number of steps, e.g., 1000, after which the
sealing member 740 should be engaged to the port 720 as shown in
FIG. 7D. In this manner, the number of steps can be used to
determine when the sealing member 740 is engaged to a particular
port without the need for including pressure sensors or flow
sensors in the manifold, though such sensors could be present if
desired.
[0069] In certain embodiments, the manifold housing can be produced
using generally inert materials to avoid unwanted reactions or
interferences with the sample. For example, the manifold housing
can be produced using stainless steel, passivated aluminum,
titanium, Inconel.RTM. alloys, perfluoroelastomers, inert plastics
and the like. In some embodiments, the entire housing of the
manifold may be produced from these materials, whereas in other
examples inner surfaces of the manifold that are exposed to fluid
may include these materials and outer surfaces of the manifold can
include materials other than the illustrative ones listed here,
e.g., steel or non-inert plastics. In some embodiments, the
longitudinal shaft of the sealing member can be sealed or shielded
from any fluid by surrounding it with a bellows assembly, a
membrane, a film, a wrap or otherwise using one or more devices or
materials to prevent fluid from contacting the longitudinal
shaft.
[0070] In certain embodiments, the manifolds described herein can
be used in a mass spectrometer to control the gating of an
interface port and one or more other ports, e.g., a roughing pump
port and a turbomolecular pump port. A basic block diagram of a
mass spectrometer system is shown in FIG. 8. The system 800
comprises a sample introduction device 800, an ionization source
820, an interface 830, a manifold 840, a vacuum system 850, a mass
spectrometer 860, a detector 870, a controller 880 and a pump 890.
The sample introduction device 810 generally is effective to
receive a liquid sample and provide small droplets of the liquid
sample in the form of an aerosol. A nebulizer is typically present
in the sample introduction device 810 to provide the aerosolized
form of a sample. In certain embodiments, the nebulizer may be a
concentric nebulizer, a cross-flow nebulizer, a Babington nebulizer
or other suitable nebulizers. The sample introduction device 810
may also include a spray chamber, e.g., a Scott or Cyclonic spray
chamber, prior to being provided to the ionization source 820. The
spray chamber can be used to provide smaller droplets to the
ionization source 820, which can create fewer analytical problems
than when large droplets are provided to the ionization source
820.
[0071] In certain embodiments, the ionization source 820 is
effective to receive the sample and atomize and ionize the species
in the sample. The ionization source may also be effective to dry
the sample by removing the solvent. Where the ionization source
takes the form of an inductively coupled plasma, the ionization
source can include a torch, e.g., a Fassel-type torch, and one or
more inductive devices electrically coupled to a generator to
provide radio frequency energy to the torch. For example, the
inductive device may be a helical coil, a flat plate electrode or
other suitable induction devices as described, for example, in
commonly assigned U.S. Pat. No. 7,511,246. In other configurations,
the ionization source may be a flame, a spark, an are, a glow
discharge or other suitable sources that can ionize sample received
from the sample introduction device 810.
[0072] In certain examples, the interface 830 is generally
configured to permit the ionization source and a lens system to
function together. The ionization source is typically at high
temperature and atmospheric pressure, which is substantially larger
than the pressure of the mass spectrometer 860. In certain
embodiments, the interface 830 can include one or more cones, e.g.,
two cones or three cones, and/or one or more lenses or both. For
example, sample can enter into the interface 830 from the
ionization source 820, and the cones can sample and skim or focus
the ion beam and reduce the pressure. Reduction in pressure can
result in expansion of the ion beam.
[0073] In certain embodiments, the manifold 840 may be any of the
manifolds described herein. The manifold 840 is shown as being
fluidically coupled to the interface 830, a chamber vacuum system
850 and a pump 890. While shown as a separate element for ease of
description, the vacuum system 850 may be considered part of the
mass spectrometer chamber. The vacuum system 850 can be fluidically
coupled to the manifold in many ways and certain illustrations are
described below in reference to FIGS. 9A-9C. The distance between
the interface 830 and the detector 870 is often around 1 meter. Any
ions entering the mass spectrometer 860 must not collide with other
molecules to reach the detector 870. The vacuum system 850 removes
gas molecules in the mass spectrometer 860 to increase the mean
free ion path (average distance traveled by ions between
collisions) and reduce the likelihood of unwanted collisions
between analyte and gases in the mass spectrometer 860. The vacuum
system 850 typically includes a turbomolecular pump. The
turbomolecular pump operates similar to a jet turbine and can
rapidly pump a chamber to a pressure of about 10.sup.-5 Ton or
less. A roughing pump 890 backs the turbomolecular pump and
evacuates the interface region.
[0074] In certain examples, as ions exit the interface region, the
sample may include a plurality of ions with different masses. Mass
filtering can be used to select the desired ions. For example, a
quadrupole is often used to select ions. Depending on the
configuration, it may be desirable to turn the desired ions at a
right angle while permitting non-ionized species and any photons to
travel in a generally straight path.
[0075] In some embodiments, the mass spectrometer 860 can include a
collision/reaction cell that can be used to remove interferences
from the ion beam. For example, polyatomic species having a mass
similar to a desired ion can be removed using the
collision/reaction cell. Illustrative collision/reaction cells and
their methods of use are described in commonly assigned US patent
application publication 20120091331. When the cell is operated in
the collision mode, the interfering species collides with inert gas
molecules, which results in removal of the interfering species
through kinetic energy discrimination. In the reaction mode,
interfering species chemically react with a reactive gas, e.g.,
ammonia, to provide a product with a different mass than the
desired ions.
[0076] In certain examples, the mass spectrometer 860 can include a
quadrupole mass filter, a time of flight analyzer, an ion trap
analyzer, or a magnetic sector analyzer or other suitable device
that is effective to separate charged ions by mass. In a typical
setup, a quadrupole mass spectrometer is used where voltages and
radio frequencies applied to the different rods permit selection of
ions with a particular mass-to-charge (m/z) ratio. The quadrupole
can be scanned at a selected rate to filter ions of different m/z
in the sample. The controller 880 can be used to select a
particular m/z ratio or to scan many different m/z ratios.
[0077] In some embodiments, the filtered ions from the mass
spectrometer are provided to a detector 870. The detector 870 may
take many different forms including, but not limited to, electron
multipliers, Faraday cups, photographic plates, a scintillation
detector or other suitable detectors. In one configuration, the
surface of a detector can be configured to release an electronic
each time an ion strikes the surface. Electrons released from the
first surface strike a second surface which releases more electrons
and amplifies the signal. This electron cascade may be continued
until a desired signal is provided.
[0078] In certain embodiments, the controller 880 typically
includes a processor and suitable circuitry to control the various
components of the system 800 and receive any signals from the
detector 880. In some embodiments, the controller 880 can be
configured to control the gas flows of the ionization source 820,
the pressure within the mass spectrometer 860 and other parameters
of the system 800 that can be adjusted for analysis of a sample.
The controller 880 can also be used to control the position of the
moveable sealing member of the manifold 840 during operation of the
system 800.
[0079] In certain examples and referring to FIG. 9A, a manifold 900
is shown comprising a first port 910 fluidically coupled to a fluid
line 915 from a backing line from a turbomolecular pump. The
manifold 900 also includes a port 920 fluidically coupled to a
fluid line 925 from a sampling interface. The manifold 900 also
includes a third port 830 fluidically coupled to a roughing pump.
In the off state of the system, a sealing member 940 is shown as
being positioned adjacent to the port 910, which prevents fluid
from the backing line from entering into the manifold 900. In this
configuration, the ionization source of the mass spectrometer is in
the off or un-ignited state and the vacuum of the system is off.
Referring to FIG. 9B, the disk shaped sealing member 940 can be
moved toward the port 920 by actuating a stepper motor (not shown),
coupled to the longitudinal shaft or rod 950, a selected number of
steps to move the sealing member 940 until it engages the port 920
and provides a substantially fluid tight seal between the port 920
and a face of the sealing member 940. As shown in FIG. 9A, the
member 940 is configured as a disk that is positioned orthogonal to
the shaft 950. In the position shown in FIG. 9B, the sealing member
940 prevents fluid flow from the interface line into the manifold
900 through the port 920. In the position shown in FIG. 9B, the
ionization source is off, but the vacuum of the system is switched
on. Referring now to FIG. 9C, the stepper motor has been actuated
back a selected number of steps to move the sealing member 940 away
from the port 920 and toward the port 910. In the position shown in
FIG. 9C, all ports are open and fluid may flow between them. In a
typical operation, the ionization source has been ignited and is
operational when the sealing member 940 is in the position shown in
FIG. 9C. The exact final position of the sealing member 940 may
vary depending on the selected fluidic conductance in the system.
In some embodiments, the ports 910, 920 and 930 may be sized
differently, and the position of the sealing member 940 can be
adjusted to account for the differences in size. In certain
embodiments, the gas load through port 920 is higher as the
sampling interface is typically close to atmospheric pressure. The
overall cross-section of the fluid flow path can be controlled by
positioning the sealing member 940 closer or further away from the
port 920. In certain embodiments, the sealing member 940 can be
positioned closer to the port 910 than the port 920 to account for
the different fluidic conductance between the various ports 910 and
920. This bias toward the port 910 reduces the overall
cross-sectional area of the port 910 and increases the
cross-sectional area of the port 920. By positioning the sealing
member 940 at a suitable position, the sampling interface pressure
can be adjusted such that the skimmer cone of the sampling
interface is well within the "zone of silence."
[0080] In certain embodiments, the sealing member 940 can include a
gasket, O-ring, film, elastomer or other device that can assist in
providing a substantially fluid tight seal between the head of the
sealing member 940 and the inner surface of the manifold 900
adjacent to a port. The gasket can be compressible such that
pressure is exerted by the sealing member 940 on the gasket when
the sealing member is positioned to engage a port of the manifold
900. In some embodiments, the actuator coupled to the sealing
member can be configured to move the sealing member a desired
amount or number of steps to permit the gasket of the sealing
member to contact the inner surface of the manifold. To ensure a
substantially fluid tight seal, the sealing member can be moved an
additional amount to apply pressure against the gasket. For
example, once gasket contacts the inner surface of the manifold, a
stepper motor can be moved an additional 50-100 steps where the
stepper motor is configured to have about 500 steps per one full
revolution of the motor. By exerting pressure against the gasket, a
desired seal can be created to prevent fluid flow from the
particular part that has been sealed.
[0081] In certain examples, a manifold such as the one shown in
FIGS. 9A-9C can be used to initiate a mass spectrometer. In the off
state, the mass spectrometer has no vacuum and no active ionization
source, e.g., where the ionization source is a plasma, the plasma
is not ignited or sustained within a torch. In one illustrative
ignition sequence to ignite the ionization source of the mass
spectrometer, the sealing member 940 will be in the position shown
in FIG. 9A, which acts to block fluid flow from the backing line
into the manifold. The sealing member 940 will then be moved to the
other side of the manifold 900 to provide a seal against the port
where the interface line couples to the manifold 900. The movement
of the sealing member from one port 910 to the other port 920 can
be performed within a desired time, e.g., 1-5 seconds. A selected
number of steps on the stepper motor can be used to determine that
the head of the sealing member 940 has been moved from the port 910
to the port 920. The roughing pump can then be switched on to pump
the chamber down to a pressure of about 1 Torr. The turbomolecular
pump of the system may then be switched on until the system reaches
full vacuum. The ionization source can then be ignited optionally
after a desired amount of time after any gas lines are purged. The
ignition source is then ignited. A pre-determined number of steps
can be used to move the head of the sealing member 940 away from
the port 920 to create a leak at the port 920. The current of the
turbomolecular pump can be monitored to ensure the sealing member
is not moved away too quickly or too far from the port 920. For
example, the current being drawn by the turbomolecular pump can be
monitored to ensure not too much fluid is entering into the
manifold. If desired, the system can be configured with a current
limit for the turbomolecular pump such that the system is switched
off if the current draw exceeds a threshold limit. In other
instances, movement of the sealing member 940 may be halted if the
current exceeds the threshold value, and once the current
stabilizes below a certain threshold, movement of the sealing
member can be reinitiated. When the turbomolecular pump current
draw stabilizes, the sealing member 940 can be moved incrementally
away from the port 920. The process of moving the sealing member
940 and monitoring the current draw can be repeated until the gas
loads stabilize and a selected fluidic conductance is achieved. The
final position of the sealing member 940 may be determined based on
the number of steps from either where the sealing member 940 is
placed against the port 920 or the net number of steps that the
sealing member 940 should be moved based on the arbitrary zero
position where the sealing member 940 is sealed against the port
910. Once the final position of the sealing member 940 has been
reached, a gate valve can be opened to permit opening of the
chamber to the mass spectrometer for analysis.
[0082] In certain embodiments, it may be desirable to permit users
of the system to adjust the final position of the sealing member to
account for altitude changes, port sizes, fluid flow rates or other
parameters. In certain examples, a user may be able to select from
two or more different final positions to provide some fine tuning
of the fluidic conductance through the manifold. For example, it
may be desirable to limit the fluidic conductance through the
interface line to provide better sensitivities for low mass
analytes such as, for example, lithium, beryllium, etc.
[0083] In some embodiments, the ports used in the manifold in a
mass spectrometer may be about 5 mm in diameter to about 50 mm in
diameter, for example, 16 mm diameter ports, 25 mm diameter ports
or 40 mm diameter ports can be present on the manifold. In some
embodiments, the backing line port may be about 16 mm in diameter,
and the interface line port may be about 25 mm in diameter. Without
wishing to be bound by any particular scientific theory, as the
ratio between the interface port size and the backing line port
size increases, the sealing member can be moved closer to the
middle of the manifold without adversely affecting the fluidic
conductance through the interface port.
[0084] In certain embodiments, the manifolds described herein can
be provided in the form of a kit, optionally with a software
program to control movement of the sealing member. If desired,
suitable fluid couplings, fluid flow lines, electrical harnesses
and other components may be included in the kits to permit
retrofitting of existing instruments and devices with the manifolds
described herein. For example, the valve assembly typically present
in existing instruments can be replaced with one of the manifolds
described herein. Suitable electrical couplings may be provided
between the controller of the system and the manifold to permit
control of the sealing member in the manifold. A firmware update
can be performed to permit hardware or software control of the
sealing member by the system.
[0085] Certain specific examples are described below to illustrate
further some of the novel aspects and attributes of the technology
described herein.
Example 1
[0086] Referring to FIG. 10, an illustration of a manifold 1000
coupled to a motor 1050 is shown. The manifold 1000 comprises a
port 1010 configured to couple to a fluid line of a turbomolecular
pump, a port 1020 configured to couple to a fluid line from an
interface and a port 1030 configured to couple to a fluid line from
a roughing pump. The motor 1050 can be configured as a stepper
motor which is coupled to an internal sealing member (hidden from
view) through the shaft 1055.
Example 2
[0087] Referring to FIG. 11, an illustration of a manifold with a
moveable, internal sealing member is shown. The manifold 1100
comprises a sealing member 1110 in the shape of a double headed
plunger. The sealing member 1110 includes O-rings 1115 and 1117 on
each end of the sealing member 1110. The sealing member also
includes a longitudinal shaft 1120 coupled to the sealing member
1110. The longitudinal shaft 1120 has a bellows assembly 1130
surrounding it to seal the shaft 1120 from any fluids that may
enter the manifold 1100. The shaft 1120 is coupled to a stepper
motor (not shown) through a rod 1140. A guide bushing 1150
surrounds the shaft 1120 to maintain movement of the shaft in a
direction substantially orthogonal to the side 1102 of the housing
of the manifold 1100. In the configuration shown in FIG. 11, the
sealing member 1110 can move a total distance of about 12 mm in the
manifold
[0088] When introducing elements of the aspects, embodiments and
examples disclosed herein, the articles "a," "an," "the" and "said"
are intended to mean that there are one or more of the elements.
The terms "comprising," "including" and "having" are intended to be
open-ended and mean that there may be additional elements other
than the listed elements. It will be recognized by the person of
ordinary skill in the art, given the benefit of this disclosure,
that various components of the examples can be interchanged or
substituted with various components in other examples.
[0089] Although certain aspects, examples and embodiments have been
described above, it will be recognized by the person of ordinary
skill in the art, given the benefit of this disclosure, that
additions, substitutions, modifications, and alterations of the
disclosed illustrative aspects, examples and embodiments are
possible.
* * * * *