U.S. patent application number 14/388477 was filed with the patent office on 2015-02-19 for solenoid device with sensor.
This patent application is currently assigned to BRT GROUP PTY LTD. The applicant listed for this patent is BRT Group Pty Ltd. Invention is credited to Richard Terrence Tamba.
Application Number | 20150047720 14/388477 |
Document ID | / |
Family ID | 49257937 |
Filed Date | 2015-02-19 |
United States Patent
Application |
20150047720 |
Kind Code |
A1 |
Tamba; Richard Terrence |
February 19, 2015 |
SOLENOID DEVICE WITH SENSOR
Abstract
A solenoid device including pressure altering means for altering
an output pressure of the solenoid device; and an actuator for
providing an actuating signal to said pressure altering means;
wherein the solenoid device further includes a sensor arranged to
sense a control value of the solenoid device, and a controller
which receives a request and is arranged to control delivery of
power to the actuator with feedback from the sensor until the
control value meets the request.
Inventors: |
Tamba; Richard Terrence;
(Castle Hill, AU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BRT Group Pty Ltd |
Castle Hill, New South Wales |
|
AU |
|
|
Assignee: |
BRT GROUP PTY LTD
Castle Hill, New South Wales
AU
|
Family ID: |
49257937 |
Appl. No.: |
14/388477 |
Filed: |
February 28, 2013 |
PCT Filed: |
February 28, 2013 |
PCT NO: |
PCT/AU2013/000189 |
371 Date: |
September 26, 2014 |
Current U.S.
Class: |
137/468 ;
137/486; 137/487.5; 137/625.69; 251/129.04 |
Current CPC
Class: |
H01F 7/1844 20130101;
Y10T 137/7761 20150401; F16K 37/0041 20130101; Y10T 137/7759
20150401; Y10T 137/7737 20150401; G05D 16/2024 20190101; Y10T
137/8671 20150401; G05D 16/2013 20130101; F16K 31/0613 20130101;
F16K 37/005 20130101; F16K 11/0716 20130101; G05D 16/2006 20130101;
G05D 7/0617 20130101 |
Class at
Publication: |
137/468 ;
251/129.04; 137/625.69; 137/486; 137/487.5 |
International
Class: |
F16K 31/06 20060101
F16K031/06; G05D 7/06 20060101 G05D007/06; G05D 16/20 20060101
G05D016/20; F16K 11/07 20060101 F16K011/07 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2012 |
AU |
2012901235 |
Claims
1.-28. (canceled)
29. A solenoid device in the form of a module, the module including
pressure altering means for altering an output pressure of the
solenoid device; and an actuator for providing an actuating signal
to said pressure altering means; wherein the solenoid device
further includes a sensor arranged to sense a control value of the
solenoid device, and a controller which receives a request and is
arranged to control delivery of power to the actuator with feedback
from the sensor until the control value meets the request.
30. The solenoid device as claimed in claim 29, wherein the
solenoid device is a solenoid spool valve including a spool valve
having a sleeve provided with a supply port, a control port, and a
spool supported in the sleeve for axial displacement within the
sleeve; and an electromagnetic actuator for providing an axial
drive force to said spool in a first axial direction; wherein the
solenoid spool valve further includes a sensor arranged to sense a
control value of the spool valve, and a controller which receives a
request and is arranged to control delivery of power to the
electromagnetic actuator with feedback from the sensor until the
control value meets the request.
31. The solenoid spool valve as claimed in claim 30, wherein the
sensor is a pressure sensor, the supply port is a supply pressure
port, the control port is a control pressure port, the control
value is a control pressure, the request is in the form of a
pressure request, and the controller controls delivery of power to
the electromagnetic actuator with feedback from the pressure sensor
until the control pressure meets the pressure request.
32. The solenoid spool valve as claimed in claim 31, wherein the
controller is in the form of a control circuit.
33. The solenoid spool valve as claimed in claim 32, wherein the
control circuit is arranged to receive the pressure request from a
communications network.
34. The solenoid spool valve as claimed in claim 33, wherein the
communications network is a Controller-Area Network.
35. The solenoid spool valve as claimed in claim 31, wherein the
pressure sensor is arranged to sense the control pressure of the
spool valve at a location inside the sleeve.
36. The solenoid spool valve as claimed in claim 31, wherein the
controller is arranged to adaptively learn current provided to the
electromagnetic actuator in relation to pressure sensed, such that
the solenoid spool valve is self-compensating.
37. The solenoid spool valve as claimed in claim 31, wherein the
controller is mounted relative to the sleeve.
38. The solenoid spool valve as claimed in claim 31, wherein the
solenoid spool valve including the pressure sensor and controller
are provided as a unitary module.
39. The solenoid spool valve as claimed in claim 31, wherein the
solenoid spool valve further includes an exhaust port, the spool
has a first piston with a first land for opening/closing the supply
pressure port and a second piston with a second land for
opening/closing the exhaust port, wherein the first piston has a
larger piston face surface area in fluid communication with the
control pressure port than does the second piston.
40. The solenoid spool valve as claimed in claim 39, wherein the
face (c) of the second piston in fluid communication with the
control pressure port is arranged such that force of fluid against
said face acts on the spool in an axial direction toward the
electromagnetic actuator.
41. The solenoid spool valve as claimed in claim 39, wherein the
spool is arranged such that, the combined force on the spool from
fluid against piston faces of the spool is independent of the
transverse extent of the first piston, owing to equal and opposite
face surface areas of the first piston.
42. The solenoid spool valve as claimed in claim 39, wherein the
first piston has one piston face (b) in fluid communication with
the control pressure port arranged such that force of fluid against
said one piston face acts on the spool in an axial direction away
from the electromagnetic actuator, and an opposite piston face (a)
in fluid communication with a feedback orifice arranged such that
force of fluid against said opposite piston face acts on the spool
in an axial direction toward the electromagnetic actuator, wherein
the feedback orifice supplies fluid at the same control pressure as
the control pressure port, wherein the feedback orifice is in fluid
communication with the control pressure port, and wherein the first
piston is cylindrical and the combined force on the spool from
fluid against piston faces of the spool is independent of an
outside diameter of the first piston.
43. The solenoid spool valve as claimed in claim 41, wherein the
spool is arranged such that, the combined force on the spool from
fluid against piston faces of the spool is given by the equation:
combined force=A+C-B, where A, B and C are the fluid forces acting
on faces a, b and c, respectively.
44. The range of solenoid spool valves, each of which is as claimed
in claim 39, wherein each of the solenoid spool valves has a
different first piston diameter to second piston diameter ratio to
provide different pressure capabilities, and wherein each of the
solenoid spool valves has an identical electromagnetic
actuator.
45. The solenoid device as claimed in claim 29, wherein the sensor
includes one or more of the following sensor types: a flow sensor,
with the control value in the form of a control flow value and the
request in the form of a flow request; a temperature sensor, with
the control value in the form of a control temperature value and
the request in the form of a temperature request; a speed sensor,
with the control value in the form of a control speed value and the
request in the form of a speed request; and a position sensor, with
the control value in the form of a control position value and the
request in the form of a position request.
46. The solenoid device as claimed in claim 29, wherein the
controller is arranged to receive the pressure request from one or
more of the following communication types: CAN, CAN-Over-Power,
radio links, or Bluetooth.
47. The solenoid spool valve as claimed in claim 34, wherein the
solenoid spool valve is arranged to use other sensors already
existing on the communications network.
48. The solenoid spool valve as claimed in claim 34, wherein there
are several like solenoid spool valves in the communications
network, and each solenoid spool valve has a unique identifier to
enable said solenoid spool valve to be operated individually.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a solenoid device and, more
particularly but not exclusively, to a solenoid spool valve having
an integrated pressure sensor which provides improved performance
characteristics when the solenoid spool valve is used in a
communications network of a vehicle or system.
BACKGROUND OF THE INVENTION
[0002] A modern vehicle typically has a large number of electronic
control units (ECU) for various subsystems. The biggest processor
is commonly the engine control unit, however other ECUs are used
for controlling other devices in the vehicle, such as the
transmission, airbags, antilock braking system, cruise control,
electric power steering, audio systems, windows, doors, mirror
adjustment, battery and recharging systems for hybrid/electric
cars, etc. Some of these form independent subsystems, but
communications among others are essential. A subsystem may need to
control actuators or receive feedback from sensors. The
Controller-Area Network (CAN) is a standard vehicle bus or
communications network devised to fill this need.
[0003] The applicant is aware that existing systems have sensors
elsewhere on a hydraulic circuit for sensing pressure delivered by
solenoid valves. The applicant has determined that such systems may
be improved, at least in so far as performance and maintenance are
concerned.
[0004] The applicant has also identified that current design high
flow solenoids have an equal area spool, meaning that lands of the
spool have the same external dimension, usually the outside
diameter, resulting in the lands having the same surface area for
driving the spool in response to fluid pressure against the lands.
To increase the pressure obtained from the current design solenoid
spool valves requires the spool diameter to be increased. As the
diameters of each of the lands on the spool increase, the force
against a diaphragm of the solenoid spool valve increases,
necessitating a magnet (coil) size of an electromagnetic actuator
to be increased. The applicant has determined that it would be
desirable to obviate the necessity to increase the magnet (coil)
size with pressure capacity of the solenoid spool valve.
[0005] Furthermore, the applicant has also identified that
increasing diameters of all lands on the spool in accordance with
current practice typically increases leakage to an exhaust port of
the solenoid spool valve, requiring a larger pump to compensate for
the leakage.
[0006] Examples of the invention seek to solve, or at least
ameliorate, one or more disadvantages of previous solenoid spool
valves.
SUMMARY OF THE INVENTION
[0007] In accordance with the present invention, there is provided
a solenoid device including pressure altering means for altering an
output pressure of the solenoid device; and an actuator for
providing an actuating signal to said pressure altering means;
wherein the solenoid device further includes a sensor arranged to
sense a control value of the solenoid device, and a controller
which receives a request and is arranged to control delivery of
power to the actuator with feedback from the sensor until the
control value meets the request.
[0008] Preferably, the solenoid device is a solenoid spool valve
including a spool valve having a sleeve provided with a supply
port, a control port, and a spool supported in the sleeve for axial
displacement within the sleeve; and an electromagnetic actuator for
providing an axial drive force to said spool in a first axial
direction; wherein the solenoid spool valve further includes a
sensor arranged to sense a control value of the spool valve, and a
controller which receives a request and is arranged to control
delivery of power to the electromagnetic actuator with feedback
from the sensor until the control value meets the request.
[0009] More preferably, the sensor is a pressure sensor, the supply
port is a supply pressure port, the control port is a control
pressure port, the control value is a control pressure, the request
is in the form of a pressure request, and the controller controls
delivery of power to the electromagnetic actuator with feedback
from the pressure sensor until the control pressure meets the
pressure request.
[0010] Preferably, the controller is in the form of a control
circuit. More preferably, the control circuit is arranged to
receive the pressure request from a communications network. Even
more preferably, the communications network is a Controller-Area
Network.
[0011] Preferably, the pressure sensor is arranged to sense the
control pressure of the spool valve at a location inside the
sleeve.
[0012] In a preferred form, the controller is arranged to
adaptively learn current provided to the electromagnetic actuator
in relation to pressure sensed, such that the solenoid spool valve
is self-compensating.
[0013] Preferably, the controller is mounted relative to the
sleeve.
[0014] It is preferred that the solenoid spool valve including the
pressure sensor and controller are provided as a unitary
module.
[0015] Preferably, the solenoid spool valve further includes an
exhaust port, the spool has a first piston with a first land for
opening/closing the supply pressure port and a second piston with a
second land for opening/closing the exhaust port, wherein the first
piston has a larger piston face surface area in fluid communication
with the control pressure port than does the second piston.
[0016] Preferably, the first piston has one piston face (b) in
fluid communication with the control pressure port arranged such
that force of fluid against said one piston face acts on the spool
in an axial direction away from the electromagnetic actuator, and
an opposite piston face (a) in fluid communication with a feedback
orifice arranged such that force of fluid against said opposite
piston face acts on the spool in an axial direction toward the
electromagnetic actuator.
[0017] More preferably, the feedback orifice supplies fluid at the
same control pressure as the control pressure port. Even more
preferably, the feedback orifice is in fluid communication with the
control pressure port. In one example, the orifice is formed as a
duct extending through the first piston to communicate with the
control pressure port.
[0018] Preferably, the face (c) of the second piston in fluid
communication with the control pressure port is arranged such that
force of fluid against said face acts on the spool in an axial
direction toward the electromagnetic actuator.
[0019] Preferably, the spool is arranged such that, the combined
force on the spool from fluid against piston faces of the spool is
independent of the transverse extent of the first piston, owing to
equal and opposite face surface areas of the first piston. More
preferably, the first piston is cylindrical and the combined force
on the spool from fluid against piston faces of the spool is
independent of an outside diameter of the first piston.
[0020] Preferably, the spool is arranged such that, the combined
force on the spool from fluid against piston faces of the spool is
given by the equation:
combined force=A+C-B,
[0021] where A, B and C are the fluid forces acting on faces a, b
and c, respectively.
[0022] In a preferred form, the first piston has a larger diameter
than the second piston. More preferably, as a result of the larger
diameter of the first piston, the valve has relatively high flow
from the supply pressure port to the control pressure port and
relatively low flow from the control pressure port to the exhaust
port.
[0023] In accordance with another aspect of the present invention,
there is provided a range of solenoid spool valves, each of which
is as described above, wherein each of the solenoid spool valves
has a different first piston diameter to second piston diameter
ratio to provide different pressure capabilities, and wherein each
of the solenoid spool valves has an identical electromagnetic
actuator.
[0024] In one particular example, each of the solenoid spool valves
has a different first piston diameter, and the same second piston
diameter.
[0025] However, a learned person can appreciate that the technology
described herein does not need to be limited to solenoids having
spool valves and could be incorporated into other solenoid types
that can alter pressure through other control means, for example,
by controlling the exhausting of oil from a control chamber, fed by
a controlled source, ie an orifice, in a controlled manner, thus
effecting pressure control. The integration of the pressure sensor
and controls in this case would be key to the repeatable pressure
output from this previously non-self-regulating
system/solenoid.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The invention is described, by way of non-limiting example
only, with reference to the accompanying drawings in which:
[0027] FIG. 1 is a solenoid spool valve with pressure sensor in
accordance with an example of the present invention;
[0028] FIG. 2(a) is a diagrammatic cross-sectional view of a
solenoid spool valve in accordance with a first example;
[0029] FIG. 2(b) is a diagrammatic cross-sectional view of a
solenoid spool valve in accordance with a second example;
[0030] FIG. 2(c) is a diagrammatic cross-sectional view of a
solenoid spool valve in accordance with a third example;
[0031] FIG. 2(d) is a diagrammatic cross-sectional view of a
solenoid spool valve in accordance with a fourth example;
[0032] FIG. 3 shows detail of a spool of a solenoid spool valve the
same or similar to those shown in FIGS. 2(a) to 2(d);
[0033] FIG. 4 is a diagrammatic view of an example system
incorporating a solenoid spool valve in accordance with the
invention;
[0034] FIG. 5 is a diagrammatic view of another example system
incorporating a plurality of solenoid spool valves in accordance
with the invention; and
[0035] FIG. 6 is a diagram showing an on board controller with a
series of possible CAN nodes.
DETAILED DESCRIPTION
[0036] With reference to FIG. 1 of the drawings, there is provided
a solenoid spool valve 10 used for supplying varying pressures from
a system supply pressure to an object (such as, for example, a
friction clutch). The solenoid spool valve 10 is advantageously
provided with a pressure sensor 46 and a controller 48 to achieve
improved performance/convenience when used in a communications
network such as a Controller-Area Network (CAN).
[0037] More specifically, the applicant has determined that
existing systems typically use a sensor elsewhere on a hydraulic
circuit, separate to the solenoid spool valve. The applicant has
determined that such arrangements are disadvantageous, particularly
when it comes to rebuilding and maintenance. Specifically, as
existing systems supply the solenoid spool valve with a current and
use an external pressure sensor to sense pressure achieved by the
solenoid spool valve, components of the system separate to the
solenoid spool valve may have to adapt to wear of the solenoid
spool valve as it may deteriorate over time and change its
characteristics. Then, when the solenoid spool valve is replaced
with a fresh solenoid spool valve, the remainder of the system must
re-learn to accommodate the new solenoid spool valve which has
different characteristics to the replaced solenoid spool valve. The
applicant has determined that it would be advantageous for there to
be provided a solenoid spool valve which has its own pressure
sensor and controller such that the solenoid spool valve is sent a
pressure request rather than a current, as is typical in existing
systems. In this way, the components of the system external to the
solenoid spool valve do not need to compensate for the change in
characteristics of the Solenoid spool valve which are dealt with
internally of the solenoid spool valve by virtue of its ability to
be self-compensating. The pressure sensor 46 is in the control
pressure circuit of the solenoid spool valve 10, and there is feed
from the CAN such that an input pressure may be requested and
controlled at the source of the signal (ie. within the solenoid).
The pressure signal is fed back to the solenoid controller 48 from
the pressure sensor 46.
[0038] More specifically, the solenoid spool valve 10 includes a
spool valve 12 having a sleeve 14 provided with a supply pressure
port 16, a control pressure port 18 and a spool 22 supported in the
sleeve 14 for axial displacement within the sleeve 14. The solenoid
spool valve 10 also includes an electromagnetic actuator 24 for
providing an axial drive force to the spool 22 in a first axial
direction away from the electromagnetic actuator 24 so as to
operate the spool valve 12. The solenoid spool valve 10 further
includes the pressure sensor 46 arranged to sense a control
pressure of the spool valve 12, and the controller 48 which
receives a pressure request and is arranged to control delivery of
power to the electromagnetic actuator 24 with feedback from the
pressure sensor 46 to meet the pressure request.
[0039] The controller 48 may receive the pressure request from the
communications network by way of communication means such as, for
example, communication wires 50. Similarly, the pressure sensor 46
may be coupled in communication with the controller 48 by way of
communication wires 52. The controller 48 shown in FIG. 1 supplies
power to the electromagnetic actuator 24 by way of power lines 54.
However, an alternative to this arrangement can be the combining of
the power and CAN wires in that the CAN signal is "injected" on top
of the power wires thus requiring only 2 wires to be connected to
the solenoid assembly.
[0040] In the example shown, the pressure sensor 46 is located in a
cavity of the sleeve 14 near a bore of the spool valve 12 so as to
sense the pressure of fluid (gas or liquid) in the control pressure
circuit in communication with the control pressure port 18. The
controller 48 is mounted relative to the sleeve 14 and may be
arranged to adaptively learn current provided to the
electromagnetic actuator 24 in relation to pressure sensed by the
pressure sensor 46, such that the solenoid spool valve 10 is
self-compensating.
[0041] Advantageously, as the solenoid spool valve 10 including the
pressure sensor 46 and controller 48 is provided as a unitary
module, the entire module is able to be replaced at the end of its
life without any need for an external controller to adapt to the
new unit as it performs its own conversion of the desired pressure
to the power requirements of the electromagnetic actuator 24.
[0042] In the example shown in FIG. 1, the solenoid spool valve 12
is a two land high flow solenoid spool valve which enables higher
control pressures to be used without necessitating a
correspondingly larger electromagnetic actuator. A similar solenoid
spool valve 12 is shown in FIG. 2(a), and is described below. In
the subsequent figures, there are shown examples of alternative
solenoid spool valves 12 which may also be adapted to include a
pressure sensor 46 and controller 48 in the manner shown in FIG. 1
so as to embody alternative configurations of the present
invention.
[0043] With reference to FIG. 2(a) there is shown a solenoid spool
valve 10 used for supplying varying pressures from a system supply
pressure to an object (such as, for example, a friction clutch).
The solenoid spool valve 10 shown has an increased supply pressure
diameter of the spool while leaving the regulated pressure end of
the spool at the original diameter. By virtue of this
configuration, the resultant force on a diaphragm of the valve 10
is independent of the increased supply pressure diameter.
[0044] More specifically, the solenoid spool valve 10 includes a
spool valve 12 having a sleeve 14 provided with a supply pressure
port 16, a control pressure port 18, an exhaust port 20 and a spool
22 supported in the sleeve 14 for axial displacement within the
sleeve 14. The solenoid spool valve 10 also includes an
electromagnetic actuator 24 for providing an axial drive force to
the spool 22 in a first axial direction away from the
electromagnetic actuator so as to operate the spool valve 12. The
spool 22 has a first piston 26 with a first land 28 for
opening/closing the supply pressure port 16, and a second piston 30
with a second land 32 for opening/closing the exhaust port 20. The
first piston 26 has a larger piston face surface area 34 in fluid
communication with the control pressure port 18 than does the
second piston 30.
[0045] The first piston 26 has one piston face (b) in fluid
communication with the control pressure port 18, arranged such that
force of fluid against the face (b) acts on the spool 22 in an
axial direction away from the electromagnetic actuator 24. The
first piston 26 also has an opposite piston face (a) in fluid
communication with a feedback orifice 36 arranged such that force
of fluid against the opposite piston face (a) acts on the spool 22
in an axial direction toward the electromagnetic actuator 24. The
feedback orifice 36 supplies fluid at the same control pressure as
the control pressure port 18. In the example shown in FIG. 2(a),
the feedback orifice 36 is formed in the sleeve 14 so as to provide
fluid at the control pressure to piston face (a) of the first
piston 26.
[0046] FIGS. 2(b) to 2(d) show alternative configurations of
solenoid spool valves 10 in accordance with other examples of the
present invention. More specifically, with reference to FIG. 2(b),
the solenoid spool valve 10 shown in this example is similar to the
example shown in FIG. 2(a), except in that the feedback orifice 36
is located in an end of the spool valve 12, rather than in a side
wall of the sleeve 14. With reference to the example shown in FIG.
2(c), the feedback orifice 36 is provided in a sidewall of the
sleeve 14 (in a manner similar to that in FIG. 2(a)), however this
example differs in that the sleeve 14 is non-circular, in contrast
to the examples in FIGS. 2(a), 2(b) and 2(d). This is made evident
by the cross-sectional depiction of the sleeve 14 in FIG. 2(c),
wherein the sleeve 14 extends to a greater degree below the spool
22 than it does above the spool 22.
[0047] The solenoid spool valve 10 shown in FIG. 2(d) has a
feedback orifice 36 formed as a duct 38 extending through the first
piston 26 to communicate with the control pressure port 18. Also,
the example shown in FIG. 2(d) incorporates a damper 40 as part of
the solenoid spool valve 10. As can be seen, the size of the magnet
42 is common to all four versions of the solenoid spool valve 10
shown in. FIGS. 2(a) to 2(d), as all four versions use an identical
electromagnetic actuator 24.
[0048] In each of the solenoid spool valves 10 shown in FIGS. 2(a)
to 2(d), the face (c) of the second piston 30 in fluid
communication with the control pressure port 18 is arranged such
that force of fluid against that face (c) acts on the spool 22 in
an axial direction toward the electromagnetic actuator 24.
[0049] With reference to FIG. 3, the spool 22 is arranged such
that, for any stationary position of the spool valve (including
when the supply pressure port 16 of the solenoid spool valve 10 is
closed as shown), the combined force on the spool 22 from fluid
against piston faces of the spool 22 is independent of the
transverse extent of the first piston 26. This independence is due
to equal and opposite face surface areas of the first piston 26,
which effectively cancel each other. Where the first piston 26 is
cylindrical, the combined force on the spool 22 from fluid against
piston faces of the spool 22 is independent of an outside diameter
of the first piston 26. With regard to the lettering shown in FIG.
3, the combined force on the spool 22 from fluid against piston
faces of the spool 22 is given by the equation:
Combined force=A+C-B, where A, B and C are the fluid forces acting
on faces (a), (b) and (c), respectively.
[0050] In this way, the force on the annular part of surface (a)
represented by the six outermost arrows of A cancel out the forces
on surface (b) represented by the six arrows of force B, such that
the combined force is truly independent of the outside diameter of
the first piston 26.
[0051] Where the spool is cylindrical, the first piston 26 has a
larger diameter than the second piston 30 so that the first piston
26 has a larger piston face surface area in fluid communication
with the control pressure port 18 than does the second piston 30.
As a result of the larger diameter of the first piston 26, the
valve 10 has relatively high flow from the supply pressure port 16
to the control pressure port 18 and relatively low flow from the
control pressure port 18 to the exhaust port 20. This is desirable,
as the relatively low flow from the control pressure port 18 to the
exhaust port 20 minimises leakage such that a smaller pump may be
used.
[0052] Advantageously, the ability to increase the diameter of the
first piston 26 enables higher control pressure to be used,
assisting in the regulation of higher pressures and facilitating
quick action of the solenoid spool valve 10. Also, as the size of
magnet 42 is independent of the flow area design, the pressure can
be adjusted by varying the diameter of the first piston 26 while
maintaining a common coil/core size between pressure/flow variants.
This may assist in maintaining an overall short length when
compared with other high flow solenoids, and facilitates the
provision of a family of solenoid designs using a common magnet
coil/core and body.
[0053] The tunable feedback orifice 36 may have a maximised effect
by being located to cooperate with the largest area of the spool
22.
[0054] The solenoid spool valve 10 may have a filled canister
whereby oil is provided inside the electromagnetic actuator to
change the natural frequency of the solenoid spool valve 10. Also,
a trimming screw 44 may be mounted as shown in FIGS. 2(a) to
2(d).
[0055] With reference to FIG. 4, there is shown a diagrammatic view
of an example system incorporating a solenoid spool valve 10 in
accordance with the invention. In the example shown, the solenoid
spool valve 10 is used in combination with a seat base/cushion 56
to control operation of the seat base/cushion. In particular, the
solenoid spool valve 10 receives information from a sensor 46 via
an on board controller (OBC) 48. The OBC is connected by wiring to
a master controller 58.
[0056] FIG. 5 shows an example system incorporating a plurality of
solenoid spool valves 10, each of which is provided with a separate
OBC 48, and an individual identifier such that the individual
solenoid spool valves 10 are able to be operated individually. The
solenoid spool valves 10 are connected by communication wires 50.
The communication wires 50 can be a combination of the power and
CAN wires such that the CAN signal is "injected" on top of the
power wires thus requiring only two wires to be connected to each
solenoid assembly. As the communication wires 50 connect to the
master controller 58 in an endless loop, this allows for continued
power and CAN communication from either direction in the even that
a wire or connection is faulty, thus making the system more robust
and failsafe.
[0057] FIG. 6 shows an OBC 48 of a solenoid spool valve 10 with a
series of possible CAN nodes that could be used by the OBC 48 to
measure responses. More specifically, the diagram shows a range of
different sensors 46 that could be used by the OBC 48 to measure
responses, depending on the nature of the request quantity type
which is received by the OBC 48. In each case, the sensor 46 is
arranged to sense a control value of the spool valve, and the OBC
48 receives a request and is arranged to control delivery of power
to the electromagnetic actuator of the solenoid spool valve 10 with
feedback from the sensor 46 until the control value meets the
request.
[0058] While various embodiments of the present invention have been
described above, it should be understood that they have been
presented by way of example only, and not by way of limitation. It
will be apparent to a person skilled in the relevant art that
various changes in form and detail can be made therein without
departing from the spirit and scope of the invention. Thus, the
present invention should not be limited by any of the above
described exemplary embodiments.
[0059] The CAN solenoid spool valve (CS) of examples of the present
invention is the combination of several technologies into one
device that enables that device to: [0060] self control its own
pressure output based on a CAN signal from a master controller;
[0061] be self compensating for wear; [0062] be self compensating
for changes in ambient conditions (ie temperature, pressure, fluid
viscosity, leakage); and [0063] be able to be commonised and
calibrated according to customer requirements by simple
programming.
[0064] In one variation of the design the CS includes a solenoid
spool valve having the ability to produce varied pressure outputs,
with the integration of a pressure sensor into the control port and
a small on-board controller that is supplied power and a CAN signal
from a master controller and is able to drive the solenoid spool to
achieve the desired pressure output independent of wear, leakage,
temperature and inlet pressure to achieve the desired result.
[0065] In another variation of the design the CS includes a
solenoid spool valve having the ability to produce varied flow
outputs, with the integration of a flow sensor into the control
port and a small on-board controller that is supplied power and a
CAN signal from a master controller and is able to drive the
solenoid spool to achieve the desired flow output or speed
independent of wear, leakage, temperature and inlet pressure to
achieve the desired result.
[0066] In another variation of the design the CS includes a
solenoid spool valve having the ability to produce varied flow
outputs, with the integration of a temperature sensor into the
control port and a small on-board controller that is supplied power
and a CAN signal from a master controller and is able to drive the
solenoid spool to achieve the desired temperature independent of
wear, leakage, temperature and inlet pressure to achieve the
desired result (ie coolant control valve).
[0067] In yet another variation of the design the CS includes a
solenoid spool valve having the ability to produce varied flow
outputs, with the integration of a speed sensor to measure engine
speed and a small on-board controller that is supplied power and a
CAN signal from a master controller and is able to drive the
solenoid spool to achieve the desired speed output independent of
wear, leakage, temperature and inlet pressure to achieve the
desired result.
[0068] In still another variation of the design the CS includes an
actuator motor having the ability to produce position control, the
integration of a position sensor onto the output and a small
on-board controller that is supplied power and a CAN signal from a
master controller and is able to drive the actuator to achieve the
desired position independent of wear, leakage, temperature and
voltage supply.
[0069] The CS controller is connected to power and can be
interconnected to the master controller via CAN as separate wires,
or can also be linked via CAN-Over-Power, radio links, Bluetooth or
otherwise as examples. The CS can also use other sensors already
existing on the CAN to effect the desired results and monitor its
performance.
[0070] The CS would automatically adjust itself to wear over its
lifetime and adjust itself to suit its environment.
[0071] The CS can be "labelled" to have a distinguishing number or
identifier so that many solenoids of the same type can be used on
the same CAN line where only the identifier is different so that
each solenoid has its own unique ID address so that when CAN
requests a pressure change, it could ask each solenoid individually
to perform the change as requested and when requested.
[0072] Using an example of a CS controlling pressure, the following
is offered: [0073] (i). Ignition is turned on in vehicle and engine
is started [0074] (ii). Driver engages Drive gear [0075] (iii).
Master controller sends a signal to the solenoid via CAN requesting
a ramp up of pressure over time to effect a smooth engagement of
drive gear in the transmission [0076] (iv). The solenoid self
regulates the pressure at the desired increasing rate as
instructed, compensating for wear, leakage and temperature to
achieve the desired rate of change of pressure [0077] (v). Once the
function is completed, the solenoid sends a signal back over CAN to
the master controller to confirm the function requested has
completed, or, the solenoid is unable to complete the task and the
reason eg. pressure too low, pressure too high, etc (error message
whereby the Master controller adopts a failsafe mode)
[0078] Variations of the invention include but are not limited to:
[0079] (a). An Idle Air Control Solenoid for Internal Combustion
Engines with an integrated speed sensor and controller that will
adjust air bleed bypass to the engine at idle to control idle speed
at the request of the engine ECU over CAN. The idle air solenoid
would automatically adjust the airflow to achieve the desired
engine idle speed based on its own integrated speed sensor. [0080]
(b). A centre-neutral logic control solenoid that would control
hydraulic oil in industrial/mining machines where the integrated
sensor(s) and controller would perform the dual purpose of
providing control pressure to the correct pressure port as directed
via CAN (left on or right on) and would feed back information to
the main machine control unit if the incorrect pressure has been
achieved, or if there is pressure caused by leakage into the
control circuit that has not been requested by the solenoid
controller, thus enabling a safety shutdown of the machine due to
unplanned/uncommanded actions. [0081] (c). Any device that requires
flow control, speed control or position control that is normally
controlled via the supplying of current or voltage to the device to
achieve control whereby the resulting feedback is not monitored and
corrected for at the device itself by the use of integrated sensors
and local control.
[0082] The reference in this specification to any prior publication
(or information derived from it), or to any matter which is known,
is not, and should not be taken as an acknowledgment or admission
or any form of suggestion that that prior publication (or
information derived from it) or known matter forms part of the
common general knowledge in the field of endeavour to which this
specification relates.
[0083] Throughout this specification and the claims which follow,
unless the context requires otherwise, the word "comprise", and
variations such as "comprises" and "comprising", will be understood
to imply the inclusion of a stated integer or step or group of
integers or steps but not the exclusion of any other integer or
step or group of integers or steps.
* * * * *