U.S. patent application number 12/195549 was filed with the patent office on 2009-02-26 for fluid compressor and control device for the same.
This patent application is currently assigned to BRIGGS AND STRATTON CORPORATION. Invention is credited to Steve Crouch, John Firoenza, Peter Nushart, Robert G. Townsend.
Application Number | 20090050219 12/195549 |
Document ID | / |
Family ID | 40381043 |
Filed Date | 2009-02-26 |
United States Patent
Application |
20090050219 |
Kind Code |
A1 |
Firoenza; John ; et
al. |
February 26, 2009 |
FLUID COMPRESSOR AND CONTROL DEVICE FOR THE SAME
Abstract
An air compressor includes a tank configured to contain
compressed air, an inlet configured to receive compressed air from
the tank, an outlet, and a control device, positioned between the
inlet and the outlet, configured to regulate an output pressure of
compressed air discharged through the outlet. The control device
includes a housing having a chamber, and a pressure regulator in
fluid communication with the chamber. The pressure regulator is
configured to regulate discharge of compressed air through the
outlet. The control device also includes a mechanical valve which,
when opened, is configured to fluidly communicate the chamber and
the tank to adjust the pressure regulator, and an actuator coupled
to the mechanical valve. The actuator is configured to at least
selectively open the valve.
Inventors: |
Firoenza; John; (Slinger,
WI) ; Crouch; Steve; (McFarland, WI) ;
Nushart; Peter; (Waukesha, WI) ; Townsend; Robert
G.; (Delafield, WI) |
Correspondence
Address: |
Michael Best & Friedrich LLP
100 East Wisconsin Avenue, Suite 3300
Milwaukee
WI
53202
US
|
Assignee: |
BRIGGS AND STRATTON
CORPORATION
Wauwatosa
WI
|
Family ID: |
40381043 |
Appl. No.: |
12/195549 |
Filed: |
August 21, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60965651 |
Aug 21, 2007 |
|
|
|
Current U.S.
Class: |
137/565.11 |
Current CPC
Class: |
F04B 49/08 20130101;
Y10T 137/85986 20150401 |
Class at
Publication: |
137/565.11 |
International
Class: |
E03B 5/00 20060101
E03B005/00 |
Claims
1. An air compressor comprising: a tank configured to contain
compressed air; an inlet configured to receive compressed air from
the tank; an outlet; a control device, positioned between the inlet
and the outlet, configured to regulate an output pressure of
compressed air discharged through the outlet, the control device
including a housing including a chamber; a pressure regulator in
fluid communication with the chamber, the pressure regulator
configured to regulate discharge of compressed air through the
outlet; a mechanical valve which, when opened, is configured to
fluidly communicate the chamber and the tank to adjust the pressure
regulator; and an actuator configured to engage the mechanical
valve, wherein the actuator is configured to at least selectively
open the valve.
2. The air compressor of claim 1, further comprising: a second
mechanical valve which, when opened, is configured to discharge
compressed air from the chamber to the atmosphere; and a second
actuator configured to engage the second mechanical valve, wherein
the second actuator is configured to at least selectively open the
second mechanical valve.
3. The air compressor of claim 2, wherein the first actuator is
configured to operate the first mechanical valve to increase the
air pressure in the chamber, and wherein the second actuator is
configured to operate the second mechanical valve to decrease the
air pressure in the chamber.
4. The air compressor of claim 3, wherein the first actuator
directly operates the first mechanical valve, and wherein the
second actuator directly operates the second mechanical valve.
5. The air compressor of claim 2, wherein the first mechanical
valve includes a first inlet and a first outlet; a first conduit
disposed between the inlet of the first mechanical valve and the
tank; a second conduit disposed between the first outlet of the
first mechanical valve and the chamber; wherein the first
mechanical valve is configured to increase the pressure in the
chamber by transferring compressed air from the tank, through the
first and second conduits, and to the chamber; and wherein the
second mechanical valve includes a second inlet and a second
outlet; a third conduit disposed between the second inlet of the
second mechanical valve and the chamber; and a fourth conduit
disposed between the second outlet of the second mechanical valve
and the atmosphere; wherein the second mechanical valve is
configured to decrease the pressure in the chamber by releasing air
from the chamber through the second mechanical valve into the
atmosphere.
6. The air compressor of claim 1, wherein the actuator is
configured as a push-button.
7. The air compressor of claim 1, wherein the valve is configured
as a three-way valve.
8. The air compressor of claim 7, wherein the actuator is
configured as a toggle positionable between a first position, in
which the chamber is fluidly isolated from the tank and the
atmosphere, a second position, in which the chamber is fluidly
communicated with the tank to adjust the pressure regulator, and a
third position, in which the chamber is fluidly communicated with
the atmosphere to discharge compressed air from the chamber into
the atmosphere.
9. The air compressor of claim 1, wherein the valve is configured
as a needle valve.
10. The air compressor of claim 1, wherein the control device
comprises a non-electrical mechanical device.
11. The air compressor of claim 1, further comprising at least one
pressure gauge in fluid communication with the outlet, wherein the
pressure gauge is configured to measure the pressure of compressed
air discharged through the outlet.
12. The air compressor of claim 11, further comprising a second
pressure gauge in fluid communication with the tank, wherein the
second pressure gauge is configured to measure the pressure of the
compressed air in the tank.
13. The air compressor of claim 1, further comprising a second
chamber at least partially defining the inlet and the outlet.
14. The air compressor of claim 13, wherein the pressure regulator
is disposed in the second chamber.
15. The air compressor of claim 14, wherein the pressure regulator
includes a movable regulatory element separating the first chamber
and second chamber, and wherein the movable regulatory element is
configured to alter the pressure in the second chamber.
16. The air compressor of claim 1, further comprising a second
chamber including a first chamber portion and a second chamber
portion, wherein the first chamber portion is in fluid
communication with the inlet and the second chamber portion is in
fluid communication with the pressure regulator and the outlet,
wherein the first chamber comprises an inlet valve chamber and an
outlet valve chamber, wherein the inlet valve chamber is in fluid
communication with the first chamber portion and the second chamber
portion, and wherein the outlet valve chamber is in fluid
communication with the second chamber portion and the
atmosphere.
17. The air compressor of claim 16, wherein the actuator includes a
lever at least partially disposed within the first chamber portion,
and wherein the lever is configured to operate the first mechanical
valve to selectively inhibit fluid communication between the inlet
valve chamber and the first chamber portion, and the first chamber
portion and the outlet valve chamber.
18. The air compressor of claim 17, further comprising: a second
mechanical valve; and a second lever at least partially disposed
within the second chamber portion, and wherein the second lever is
configured to operate the second mechanical valve to selectively
inhibit fluid communication between the second chamber portion and
the outlet valve chamber.
19. The air compressor of claim 1, further comprising a return
spring coupled to one of the actuator and the valve, wherein the
return spring is configured to bias the valve to a closed position.
Description
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application Ser. No. 60/965,651 filed on Aug. 21, 2007, the entire
content of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to fluid compressors, and more
particularly to control devices for fluid compressors.
BACKGROUND OF THE INVENTION
[0003] Fluid (e.g., air) compressors typically include a pressure
regulator to regulate the pressure of the compressed air that is
delivered to pneumatic tools or other accessories used with the air
compressor. Conventional pressure regulators typically include an
internal seal or piston movable against the bias of a spring
positioned within the pressure regulator housing. Conventional
pressure regulators also typically include a knob rotatably coupled
to the pressure regulator housing to actuate the spring. Clockwise
rotation of the knob (viewing from a position facing the knob)
typically increases the compression of the spring to impart a
greater force on the piston, thereby increasing the amount of
airflow past the piston and ultimately the regulated pressure.
Counter-clockwise rotation of the knob typically decreases the
compression of the spring to impart a lesser force on the piston,
thereby decreasing the amount of airflow past the seal and
ultimately the regulated pressure.
[0004] Adjusting a conventional pressure regulator typically
requires a large amount of effort because an operator would
encounter increased resistance in turning the knob to increase the
regulated pressure as a result of the increased compression of the
spring. As such, adjusting a conventional pressure regulator from
fully closed to fully open can take as long as 15 to 20 seconds. In
addition, it is often difficult to accurately set a conventional
pressure regulator to a desired regulated pressure setting because
the increasing resistance to rotation of the knob as the regulated
pressure setting is increased often causes an operator to overshoot
the desired setting. The operator must then incrementally turn the
knob in the opposite direction to bleed pressure from the regulator
to achieve the desired regulated pressure setting. Further, the
effects of hysteresis in the spring may further complicate
achieving an accurate regulated pressure setting.
SUMMARY OF THE INVENTION
[0005] The present invention provides, in one aspect, an air
compressor including a tank configured to contain compressed air,
an inlet configured to receive compressed air from the tank, an
outlet, and a control device, positioned between the inlet and the
outlet, configured to regulate an output pressure of compressed air
discharged through the outlet. The control device includes a
housing having a chamber, and a pressure regulator in fluid
communication with the chamber. The pressure regulator is
configured to regulate discharge of compressed air through the
outlet. The control device also includes a mechanical valve which,
when opened, is configured to fluidly communicate the chamber and
the tank to adjust the pressure regulator, and an actuator coupled
to the mechanical valve. The actuator is configured to at least
selectively open the valve.
[0006] Other features and aspects of the invention will become
apparent by consideration of the following detailed description and
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a front perspective view of a control device of
the present invention coupled to a pressure regulator of a fluid
compressor.
[0008] FIG. 2 is a rear perspective view of the control device and
pressure regulator of FIG. 1.
[0009] FIG. 3 is a cross-sectional view of the control device and a
portion of the pressure regulator of FIG. 1, illustrating the
control device fluidly connected to a source of compressed
fluid.
[0010] FIG. 4 is a cross-sectional view of the control device and
the pressure regulator of FIG. 1, illustrating a valve assembly in
the pressure regulator in a fully closed position.
[0011] FIG. 5 is a cross-sectional view of the control device and
the pressure regulator of FIG. 1, illustrating the valve assembly
in the pressure regulator in a fully opened position.
[0012] FIG. 6 is a cross-sectional view of an alternate
construction of a control device of the present invention coupled
to a pressure regulator of a fluid compressor.
[0013] FIG. 7 is a front perspective view of an alternate
construction of a control device for the present invention.
[0014] FIG. 8 is a vertical cross-sectional view of the control
device of FIG. 7 along line 8-8 in FIG. 7, illustrating the
pressure regulator and the first and second chambers.
[0015] FIG. 9 is a horizontal cross-sectional view of the second
chamber of the control device of FIG. 7 along line 9-9 in FIG.
8.
[0016] FIG. 10 is a cross-sectional view along the width of the
control device of FIG. 7 along line 10-10 of FIG. 9, illustrating
the pressure regulator.
[0017] FIG. 11 is a front perspective view of a three-position
switch.
[0018] Before any embodiments of the invention are explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting. The use of "including,"
"comprising," or "having" and variations thereof herein is meant to
encompass the items listed thereafter and equivalents thereof as
well as additional items. Unless specified or limited otherwise,
the terms "mounted," "connected," "supported," and "coupled" and
variations thereof are used broadly and encompass both direct and
indirect mountings, connections, supports, and couplings. Further,
"connected" and "coupled" are not restricted to physical or
mechanical connections or couplings.
DETAILED DESCRIPTION
[0019] FIGS. 1 and 2 illustrate a pressure regulator assembly 10
including a control device 14 and a pressure regulator 18 coupled
to the control device 14. The control device 14 includes a housing
22 having a flange 26 at one end of the housing 22, and the
pressure regulator 18 includes a body 30 having a mating flange 34
(see FIG. 2) coupled to the flange 26 of the housing 22 using
fasteners or the like. In the illustrated construction of the
pressure regulator assembly 10, the housing 22 is made from a
plastic material, and the regulator body 30 is made from metal
using a die-casting process. Alternatively, the housing 22 may also
be made from metal using a die-casting process.
[0020] The regulator body 30 includes an inlet 38 in fluid
communication with a source 42 of pressurized fluid (e.g., a tank
of pressurized air or other gas, see FIG. 3) and an outlet 46 (see
FIGS. 4 and 5) through which a regulated supply of pressurized
fluid is selectively discharged. The regulator body 30 also
includes a cylindrical bore 50 that slidably receives a piston 54
having a face 58 and a rearwardly-projecting stem 62. As shown in
FIGS. 4 and 5, the bore 50 is in fluid communication with the
outlet 46 in the regulator body 30.
[0021] The pressure regulator 18 includes an internal valve
assembly 66 positioned in the regulator body 30 that is selectively
adjustable to provide pressurized fluid at a desired regulated
pressure to pneumatic tools or other pneumatic accessories. With
continued reference to FIGS. 4 and 5, the internal valve assembly
66 includes a valve holder 70 secured to the regulator body 30
using fasteners, a press-fit, or the like. The valve holder 70
includes a stepped passageway 74 defining an inlet end 78 in fluid
communication with the inlet 38 in the regulator body 30 and in
selective fluid communication with the bore 50, and an outlet end
82 in fluid communication with the bore 50. The valve assembly 66
also includes a seal member 86 received through the inlet end 78 of
the stepped passageway 74 and selectively abutted against a stepped
surface 90 in the passageway 74 (see FIG. 4). The valve assembly 66
further includes a biasing member 94 (e.g., for example, a
compression spring) positioned between the regulator body 30 and
the seal member 86 to bias the seal member 86 against the stepped
surface 90.
[0022] In the illustrated construction of the seal member 86, the
seal member 86 includes a plurality of longitudinally-extending
ribs around its outer periphery. The radially-outermost surfaces of
the ribs slidably engage an interior wall 98 of the passageway 74
to center the seal member 86 in the passageway 74 and to guide the
seal member 86 as it moves in the passageway 74. The seal member 86
also includes a plurality of longitudinally-extending grooves
defined between respective pairs of ribs. Each of the grooves
includes a radially-innermost surface spaced from the interior wall
98 of the passageway 74. As such, a combination of the
radially-innermost surfaces of the respective grooves and the
interior wall 98 of the passageway 74 define a plurality of
longitudinally-extending channels through the seal member 86.
[0023] With reference to FIGS. 1 and 2, the housing 22 of the
control device 14 includes another flange 102 having dual,
user-actuated, push-button needle valves 106, 110 coupled to the
flange 102. Each of the valves 106, 110 includes a body 114, an
internal passageway in the body 114 (not shown), a plunger
positioned within the passageway (also not shown), an inlet 118 in
fluid communication with the passageway, an outlet 122 in fluid
communication with the passageway, and an actuator, configured as a
push-button 126, coupled to the plunger. At least a portion of the
body 114 of each of the valves 106, 110 is threaded to receive a
nut having matching threads. The valves 106, 110 may be threaded
directly into threaded apertures in the flange 102 of the housing
22. Alternatively, the threaded portions of the valves 106, 110 may
be inserted through respective apertures in the flange 102, and
respective jam nuts may be utilized to clamp the valves 106, 110 to
the flange 102. Such valves 106, 110 are commercially available
from The Specialty Manufacturing Co. of St. Paul, Minn.
[0024] In an alternative construction of the control device 14, a
single routing valve or a multi-function routing valve may be
utilized rather than the dual needle valves 106, 110. Such a
routing valve and a multi-function routing valve are also
commercially available from The Specialty Manufacturing Co. of St.
Paul, Minn.
[0025] With reference to FIG. 3, the housing 22 includes a chamber
130 and an aperture 134 in the flange 26 that fluidly communicates
the chamber 130 and the portion of the bore 50 in the regulator
body 30 between the piston 54 and the flange 34. The housing 22
also includes dual apertures 138 in a side wall 142 of the housing
22. As shown in FIG. 2, a conduit 146 (e.g., a flexible tube) is
coupled to the outlet 122 of the valve 106 and inserted through one
of the apertures 138 to fluidly communicate the valve outlet 122
and the chamber 130. Likewise, a conduit 150 is coupled to the
inlet 118 of the valve 110 and inserted through the other aperture
138 to fluidly communicate the valve inlet 118 and the chamber 130.
A third conduit 154 is coupled to the inlet 118 of the valve 106
and routed through an aperture 158 in the flange 26, which, in
turn, is in fluid communication with the inlet 38 of the regulator
body 30 which is exposed to the source 42 of compressed fluid (see
FIG. 3).
[0026] During operation of the pressure regulator 18, axial
movement of the piston 54 in the bore 50 is transferred to the seal
member 86 by the stem 62, which is abutted against a sealing
surface 162 of the seal member 86. FIG. 4 illustrates the pressure
regulator 18 in a fully-closed configuration such that compressed
fluid in the inlet 38 of the regulator body 30 is prevented from
flowing through the valve assembly 66 and into the outlet 46 of the
regulator body 30. Specifically, the stepped surface 90 extends
radially inwardly further than the respective radially-innermost
surfaces of the grooves in the seal member 86. As such, the sealing
surface 162 of the seal member 86 seals against the stepped surface
90 when the seal member 86 is abutted against the stepped surface
90 to substantially prevent pressurized fluid from flowing through
the inlet end 78 of the passageway 74, through the channels, around
the stepped surface 90, and into the bore 50 and outlet 46 in the
regulator body 30. As indicated by arrows A in FIG. 4, compressed
fluid in the inlet 38 of the regulator body 30 cannot flow through
the channels and around the stepped surface 90 in the passageway 74
when the sealing surface 162 of the seal member 86 is abutted
against the stepped surface 90.
[0027] When the sealing surface 162 of the seal member 86 is
displaced from the stepped surface 90 by axial movement of the
piston 54, pressurized fluid in the inlet 38 of the regulator body
30 is permitted to flow through the inlet end 78 of the passageway
74, through the channels and around the stepped surface 90, through
the outlet end 82 of the passageway 74, through the portion of the
bore 50 between the piston 54 and the valve assembly 66, and
through the outlet 46 of the regulator body 30 (indicated by arrows
B in FIG. 5). FIG. 5 illustrates the pressure regulator 18 in a
fully-opened configuration, such that the regulated output pressure
to a pneumatic tool or other pneumatic accessory is substantially
the same as the regulated tank pressure. The pressure regulator 18
may be adjusted to provide any of a number of different regulated
output pressures between the fully-closed and fully-opened
configurations, with increased displacement of the sealing surface
162 of the seal member 86 from the stepped surface 90 yielding an
increased regulated output pressure.
[0028] With reference to FIG. 4, the control device 14 is operable
to move or displace the piston 54 in the bore 50 of the regulator
body 30, thereby moving or displacing the seal member 86 with
respect to the stepped surface 90 to adjust the regulated output
pressure of the compressed fluid discharged from the outlet 46 in
the regulator body 30. Starting in the fully-closed configuration
shown in FIG. 4, to increase the regulated output pressure of the
compressed fluid discharged from the outlet 46 in the regulator
body 30, one would depress the push-button 126 of the valve 106 to
fluidly communicate the source 42 of compressed fluid, via the
inlet 38 in the regulator body 30, with the chamber 130, permitting
compressed fluid from the source 42 to flow through the conduit
154, through the valve 106, through the conduit 146, and into the
chamber 130 (see FIGS. 1-3). Flooding the chamber 130 with
pressurized fluid from the source 42 increases the pressure in the
chamber 130 and the resultant force of the compressed fluid acting
on the face 58 of the piston 54. The piston 54 is axially movable
as a result of an imbalance between this resultant force on the
face 58 of the piston 54 and the force exerted on the seal member
86 and the stem 62 of the piston 54 by the biasing member 94 (see
FIGS. 4 and 5). The piston 54 will continue to move until the
resultant force on the face 58 of the piston 54 is balanced with
the force exerted on the seal member 86 and the stem 62 of the
piston 54 by the biasing member 94.
[0029] With reference to FIG. 4, as pressurized fluid floods the
chamber 130, and as the pressure within the chamber 130 becomes
sufficiently high to overcome the force exerted by the biasing
member 94 on the seal member 86 and piston 54 to bias the seal
member 86 against the stepped surface 90, the piston 54 and seal
member 86 are pushed leftward, against the bias of the biasing
member 94. However, because the illustrated biasing member 94 is
configured as a compression spring, the force exerted by the
biasing member 94 on the seal member 86 and piston 54 increases
linearly according to the value of the spring rate of the biasing
member 94. As such, a proportionally increasing pressure is
required in the chamber 130 to continue to push the piston 54 and
seal member 86 leftward toward the fully-opened position. The
position at which the piston 54 comes to rest within the bore 50
and the position at which the seal member 86 comes to rest within
the passageway 74 is dependent upon the pressure of the compressed
fluid in the chamber 130.
[0030] With reference to FIGS. 2 and 3, to decrease the regulated
output pressure of the compressed fluid discharged from the outlet
46 in the regulator body 30, one would depress the push-button 126
of the valve 110 to exhaust the compressed fluid in the chamber 130
through the conduit 150 and the valve 110 to the atmosphere or
outside surroundings of the housing 22. Alternatively, another
conduit may be coupled to the outlet 122 of the valve 110 to
selectively fluidly communicate the chamber 130 and a storage
device configured to store the fluid (e.g., a storage tank), in a
compressed state or an uncompressed state, after it is discharged
or exhausted from the chamber 130.
[0031] In an alternative construction of the control device 14
utilizing a single routing valve or a multi-function routing valve,
a single conduit may be fluidly connected between the inlet 38 of
the regulator body 30 and a first port of the routing valve, a
second conduit may be fluidly connected between a second port of
the routing valve and the chamber 130, and the routing valve may
include a third port exhausted to atmosphere or fluidly connected
to a storage device (e.g., a storage tank). To increase the
regulated output pressure of the compressed fluid in the outlet 46
of the regulator body 30, a switch on the routing valve could be
actuated to a first position in which the first and second ports of
the routing valve are fluidly connected, thereby flooding the
chamber 130 with pressurized fluid from the source 42. To decrease
the regulated output pressure of the compressed fluid in the outlet
46 of the regulator body 30, the switch on the routing valve could
be actuated to a second position in which the second and third
ports of the routing valve are fluidly connected, thereby
permitting the pressurized fluid in the chamber 130 to exhaust to
atmosphere or to be discharged to a storage device.
[0032] As compressed fluid is exhausted from the chamber 130, the
pressure in the chamber 130 and the resultant force acting upon the
face 58 of the piston 54 decreases, causing a force imbalance
between the resultant force on the face 58 of the piston 54 and the
biasing member 94 that pushes the piston 54 and seal member 86
rightward with respect to the orientation of the assembly 10 in
FIGS. 3 and 4. In a manner similar to that described above for
increasing the regulated output pressure, the piston 54 and seal
member 86 will continue to move until the resultant force on the
face 58 of the piston 54 is balanced with the force exerted on the
seal member 86 and the stem 62 of the piston 54 by the biasing
member 94.
[0033] In this manner, the control device 14 is operable to rapidly
adjust the regulated output pressure of the pressurized fluid
discharged from the outlet 46. For example, a user desiring to
adjust the pressure regulator 18 from its fully-closed position
(see FIG. 4) to its fully-opened position (see FIG. 5) can do so by
repeatedly pressing, or depressing and holding the push-button 126
of the valve 106 to flood the chamber 130 with compressed fluid
having a pressure sufficient to push the piston 54 and seal member
86 to the position shown in FIG. 5. Such an operation may take as
little as about 3 seconds.
[0034] In addition, the control device 14 is operable to allow
adjustment of the regulated output pressure of the pressurized
fluid discharged from the outlet 46 in small or fine increments. In
other words, a user may depress either of the push-buttons 126 of
the valves 106, 110 in short bursts to effectuate a small change in
pressure in the chamber 130, resulting in proportionally small
incremental axial movements of the piston 54 and seal member 86 and
incremental adjustment of the regulated output pressure of the
pressurized fluid discharged from the outlet 46.
[0035] At no time during the operation of the control device 14 is
electrical power utilized to flood the chamber 130 of the control
device 14 with compressed fluid or exhaust compressed fluid from
the chamber 130 to adjust the regulated output pressure of the
compressed fluid discharged from the outlet 46 of the regulator
body 30. The control device 14 is operable to adjust the regulated
output pressure of the compressed fluid discharged from the outlet
46 of the regulator body 30 using only the pressure of the
compressed fluid accumulated in the source 42 as the driving force
to transfer compressed fluid from the source 42 to the chamber 130
of the control device 14.
[0036] In addition, the user-actuated valves 106, 110 are manually
operated by the user of the fluid compressor either directly or
through a mechanical linkage. As a result, electrical power is not
required to operate the valves 106, 110 in the manner discussed
above, thereby reducing the cost and complexity of the control
system. Further, the effort by the user in adjusting the regulated
output pressure is limited to the substantially constant,
relatively small force required to depress the push-buttons 126 of
the valves 106, 110. The driving force to compress the biasing
member 94 is provided by the pressure of the compressed fluid in
the source 42.
[0037] The control device 14 also provides added flexibility to how
fluid compressors are configured and fluid compressor components
are packaged. For example, pressure regulators in conventional
fluid compressors are typically located toward the front of the
compressor and positioned so that users can easily grasp the knob
of the regulator to turn it. However, the control device 14 allows
the major structural components of the pressure regulator assembly
10, e.g., the pressure regulator 18 and control device housing 22,
to be remotely positioned from the valves 106, 110. As such, the
valves 106, 110 may be positioned toward the front and upper
portion of the compressor so that they are easily reached by users,
while the remaining components of the pressure regulator assembly
10 may be positioned toward the rear of the compressor or lower on
the compressor, in an effort to provide a more aesthetically
pleasing packaging configuration of the compressor.
[0038] With reference to FIG. 6, an alternative construction of a
control device 166 includes a housing 170 including a chamber 174,
an interior wall 178 separating the chamber 174 into a first
chamber portion 182 and a second chamber portion 186, an inlet
valve chamber 190, an outlet valve chamber 194, and a wall 198
separating the inlet valve chamber 190 from the outlet valve
chamber 194. The illustrated control device 166 also includes at
least a portion of a pressure regulator 202 integrally formed with
the control device housing 170. Alternatively, the control device
166 may be coupled to a separate pressure regulator, such as the
pressure regulator 18 illustrated in FIGS. 1, 2, 4, and 5, using
fasteners or the like.
[0039] With reference to FIG. 6, an inlet valve assembly 206 is
positioned in the inlet valve chamber 190. The inlet valve assembly
206 includes an actuator, configured as a lever or arm 210
pivotably coupled to a mount 214, and an elastomeric (e.g., for
example, rubber) valve or seal 218 coupled to one end of the arm
210. The actuator also includes a push-button 222 coupled to the
other end of the arm 210. The push-button 222 extends through a top
cover 226 of the housing 170 and a biasing member 230 (e.g., for
example, a compression spring) is positioned beneath the
push-button 222 on a perch 234.
[0040] An outlet valve assembly 238 is positioned in the outlet
valve chamber 194. The outlet valve assembly 238 includes an
actuator, configured as a lever or arm 242 pivotably coupled to a
mount 246, and an elastomeric (e.g., for example, rubber) valve or
seal 250 coupled to one end of the arm 242. The actuator also
includes a push-button 254 coupled to the other end of the arm 242.
The push-button 254 extends through the top cover 226 of the
housing 170 and a biasing member 258 (e.g., for example, a
compression spring) is positioned beneath the push-button 254 on a
perch 262.
[0041] With continued reference to FIG. 6, the housing 170 includes
an inlet 266 in fluid communication with the first chamber portion
182. The inlet 266 is fluidly connected to the source 42 of
pressurized fluid, such that the pressure of pressurized fluid in
the first chamber portion 182 is substantially the same as the
pressure in the source 42. The housing 170 also includes an
aperture 270 selectively fluidly communicating the first chamber
portion 182 and the inlet valve chamber 190, an aperture 274
selectively fluidly communicating the inlet valve chamber 190 and
the second chamber portion 186, an aperture 278 selectively fluidly
communicating the second chamber portion 186 and the outlet valve
chamber 194, and an aperture fluidly communicating the outlet valve
chamber 194 to the atmosphere or to a storage device (e.g., for
example, a storage tank).
[0042] The control device 166 is operable in a similar manner as
the control device 14 of FIGS. 1-5. To increase the regulated
output pressure of the compressed fluid in an outlet 282 of the
pressure regulator 202, one would depress the push-button 222,
causing the end of the arm 210 having the seal 218 to pivot
upwardly to unseat the seal 218 from a position covering the
apertures 270, 274 to permit compressed fluid in the first chamber
portion 182 to flood the inlet valve chamber 190 and the second
chamber portion 186. Increasing pressure of the compressed fluid in
the second chamber portion 186 causes a piston 286 in the pressure
regulator 202 to axially displace in the same manner as discussed
above with respect to the pressure regulator assembly 10 of FIGS.
1-5.
[0043] To decrease the regulated output pressure of the compressed
fluid in the outlet 282 of the pressure regulator 202, one would
depress the push-button 254, causing the end of the arm 242 having
the seal 250 to pivot upwardly to unseat the seal 250 from a
position covering the aperture 278 to permit compressed fluid in
the second chamber portion 186 to exhaust to the outlet valve
chamber 194 and subsequently to the atmosphere or a storage
device.
[0044] In an alternative construction as depicted in FIGS. 7-10,
the control device 300 is located between the inlet 304 that
receives the intake air from the source of compressed air and the
outlet 308. The control device 300 may be affixed using fasteners,
such as screws 310, within an outer housing 312 comprising a back
portion 314 and a front plate 318, as shown in FIG. 7.
[0045] In reference to FIG. 7, the control device 300 includes a
housing 320 including a first chamber 324 and a second chamber 328,
and a pressure regulator 332 (see FIG. 8) in fluid communication
with the first chamber 324 and the second chamber 328. The pressure
regulator 332 may be enclosed within the pressure regulator body
336, which may be integrally formed with the second chamber 328.
The pressure regulator 332 is structurally similar to the pressure
regulator 18 described above and shown in FIGS. 4 and 5. The first
324 and second 328 chambers may be joined by fasteners 340 or the
like. The inlet 304 includes an input aperture 344, which may be a
quick release connector, in fluid communication with the source of
pressurized fluid, e.g. a tank of pressurized air such as tank 42
in FIG. 3. The outlet 308 includes an outlet aperture 348 through
which a regulated supply of pressurized fluid is selectively
discharged. The outlet 308 may include a quick connect collar 350.
A first mechanical valve 352 is mechanically linked with an
actuator, such as a push-button 384.
[0046] As used herein, "mechanically linked" and "mechanical
linkage" refer to either a direct engagement between two members
(i.e. an actuating member and a valve) or an indirect engagement
wherein there is one or more non-electrical, mechanical intervening
components (e.g. a lever or link arm) between the two elements.
[0047] With reference to FIG. 7, the first mechanical valve 352
includes an inlet 356 and an outlet 360. The inlet 356 is in fluid
communication with the source of intake air, and the outlet 360 is
in fluid communication with the first chamber 324. A conduit 362 is
in fluid flow communication with the inlet 356 of the first
mechanical valve 352 at one end of the conduit 362, and in fluid
flow communication with the input air in the inlet portion 372 of
the second chamber at an opposite end of the conduit 362 (see also
FIG. 8). A barb fitting 368 may be utilized to secure the conduit
362 to a flange 366 on the housing 320, thereby fluidly
communicating the conduit 362 and the intake portion 372 of the
second chamber 328 via an aperture 370. With reference to FIG. 7, a
second conduit 374 is in fluid flow communication with the first
outlet 360 of the first mechanical valve 352 at one end of the
conduit 374, and in fluid flow communication with the first chamber
324 at an opposite end of the conduit 374. A barb fitting 380 may
be utilized to secure the conduit 374 to a flange 378 on the first
chamber body, thereby fluidly communicating the conduit 374 and the
first chamber 324. Depressing the push-button 384 causes the first
mechanical valve 352 to open, pressurizing the first chamber 324
with pressurized air and thus increasing the pressure in the first
chamber 324. The increased pressure in the first chamber 324
actuates the pressure regulator to alter the pressure in the second
chamber 328 and the output pressure.
[0048] In reference to FIG. 7, a second mechanical valve 386 is
mechanically linked with a second actuator, such as a second
push-button 388. The second mechanical valve 386 includes an outlet
390 and an inlet 392, the outlet 390 in fluid communication with
the atmosphere, and the inlet 392 in fluid communication with the
first chamber 324. A third conduit 394 is disposed between the
outlet 390 of the second mechanical valve 386 and the atmosphere. A
fourth conduit 396 is in fluid flow communication with the inlet
392 of the second mechanical valve 386 at one end of the conduit
396, and in fluid flow communication with the first chamber 324 at
an opposite end of the conduit 396. A barb fitting 400 may be
utilized to secure the conduit 396 to a flange 402 on the first
chamber body, thereby fluidly communicating the conduit 396 and the
first chamber 324. Depressing the second push-button 388 causes the
opening of the second mechanical valve 386, allowing release of
pressure within the first chamber 324 through the second mechanical
valve 386 to the atmosphere.
[0049] Alternatively, a single, multiple-position valve 410 may be
substituted for the first and second mechanical valves 352, 386 to
change or adjust the pressure of the compressed air in the chamber
324 (see FIG. 11). The valve 410 may include a first passageway
selectively fluidly communicating the tank 42 and the chamber 324,
a second passageway selectively fluidly communicating the chamber
324 and the atmosphere, and a plunger moveable between a first
position, in which both the first and second passageways are
closed, a second position, in which only the first passageway is
opened, and a third position, in which only the second passageway
is opened. The valve 410 may also include an actuator, configured
as a toggle, which when positioned in a neutral position 500, both
of the first and second passageways in the valve 410 are closed.
Movement of the toggle to an increase position 510 actuates the
plunger to fluidly communicate the tank 42 and the chamber 324,
thereby flooding the chamber 324 with compressed air from the tank
42 and increasing the pressure of the compressed air in the first
chamber 324. Movement of the toggle to a decrease position 520
actuates the plunger to fluidly communicate the chamber 324 and the
atmosphere to discharge compressed air in the chamber 324 to the
atmosphere, thereby decreasing the pressure in the compressed air
in first chamber 324. Such a valve 410, and other valve designs or
configurations that can provide the above-described functionality,
are commercially available from The Specialty Manufacturing Co. of
St. Paul, Minn.
[0050] In reference to FIGS. 7, 9, and 10, a first pressure gauge
420 is configured to measure the output pressure from the control
device 300. The first pressure gauge 420 may be located within an
aperture 422 in fluid communication with the pressure regulator
body 336. A second pressure gauge 430 may be configured to measure
the pressure of the intake air or tank pressure. The second
pressure gauge 430 may be located in an aperture 432 of the intake
portion 372 of the second chamber 328.
[0051] In reference to FIGS. 8 through 10, the pressure regulator
332 may be disposed between the first chamber 324 and second
chamber 328. The pressure regulator 332 includes a movable
regulatory element such as a piston 440 located within a bore 444,
a seal member 448 including a stem 454 engaged with the piston 440,
and a biasing member 450 biasing the stem 454 of the seal member
448 against the piston 440. In operation of the control device 300,
the force on the face 442 of the piston 440 in the first chamber
324 is balanced with the force exerted on the seal member 448 and
stem 454 of the piston 440 by the biasing member 450 in a similar
manner to the embodiments described above. The operation of the
pressure regulator 332 is substantially similar to the operation of
the pressure regulator 18 described above, and will not be
described again in detail. A change in pressure in the first
chamber 324 by pressing push-button 384 causes a change in the
resultant force acting on the face of the movable regulator
element, in turn increasing the pressure of the second chamber 328
and the output pressure. In reference to FIG. 8, pressurized fluid
from the inlet 304 flows through the inlet portion 372 of the
second chamber 328 and around the seal member 448 to provide a
regulated supply of pressurized fluid, at an output pressure
determined by the control device 300, through the outlet portion
460 of the second chamber 328.
[0052] Various features and advantages of the invention are set
forth in the following claims.
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