US2988100A

US2988100A - Pneumatic relay system

Info

Publication number: US2988100A
Authority: US
Inventors: Jr Robert W Couffer
Original assignee: Dole Valve Co
Current assignee: Dole Valve Co
Priority date: 1959-02-09
Filing date: 1959-02-09
Publication date: 1961-06-13
Anticipated expiration: 1978-06-13

Description

June 13, 1961 R. w. COUFFER, JR

PNEUMATIC RELAY SYSTEM Filed Feb. 9, 1959 2 Sheets-Sheet 1 LFEYZZZZJ June 13, 1961 R. w. COUFFER, JR 2,988,100

PNEUMATIC RELAY SYSTEM Filed Feb. 9, 1959 2 Sheets-Sheet 2 v f 2 I 88 90 #0 95 @1 80 H7 94 g 107 1 I08 J 177 93 98 102 J 99 m5 I20 I06 I I13 7U 7U 45 x 42.

in, a 45 w 45 1 4,4, 64 M- he HILL? Rob ere W Goa/fez" (/27 United States Patent 2,988,100 PNEUMATIC RELAY SYSTEM Robert W. Conifer, Jr., Oak Park, Ill., assignor to The Dole Valve Company, Morton Grove, 111., a corporation of Illinois Filed Feb. 9, 1959, Ser. No. 792,166 6Claims. (Cl. 137-102) This invention is directed generally to pneumatic relay systems and the like and is more particularly directed to a pneumatic relay system particularly adapted to be used in controlling the electric and pneumatic actuation of various mechanisms such as might be found in a washing machine.

In recent years it has been found to be quite advantageous to control the operation of various component parts of washing machines, such as the agitator mechanism, the shut oil and/ or mixing valve, the cycling mechanism, etc. pneumatically and to provide a central pneumatic relay system coupled with a suitable timing mechanism to efiect actuation of each of these components.

It will be understood that such pneumatic systems require a pneumatic pump to feed pressurized air to the timing device or to the individual pneumatically controllable mechanisms and that a power source must be utilized to drive the air pump of the pneumatic system. In the past, such pneumatic pumps have generally been driven through separate electric motors and gear reduction units or have been driven oil the main washing machine motor itself constantly throughout the washing machine cycle. The foregoing means for driving the pneumatic pump have not proved entirely satisfactory, however, for the following reasons: Washing machine motors, as is well known in the art, are generally onethird horsepower units, or less, and are frequently used to full capacity at various points in the cycle of operation of the washing machine so that any additional load which the motor might be subjected to, such as the load applied in operating a pneumatic pump, would tend to overload the motor and the machine would stop. For examplary purposes, it will be noted that the main motor might be used to full capacity in a situation wherein the machine cycle is stopped by the operator and is again restarted during the rinse operation so that the motor must bring the tub full of water and clothes up to the spin speed. Furthermore, it would obviously not be economically practical to substantially increase the horsepower of the main washing machine motor simply topower a pneumatic pump. In this same regard, it is obviously not economically practical to provide a separate electric motor and gear reduction unit for driving the pneumatic pump for a pneumatic relay system as has been done in the past.

Mindful of the foregoing and in an attempt to obviate the disadvantageous features set forth above, applicant has devised a pneumatic relay system including a pneumatic pump wherein the pump is driven intermittently by the main washing machine motor but wherein the main motor is not utilized to operate the air pump during those intervals when machine loads are applied to the motor.

In general, applicants pneumatic relay system, which is hereinafter set forth with particularity, includes a pneumatic pump having a reciprocably movable compressor diaphragm therein and having a reservoir associated therewith which is associated with the main washing machine motor in such a manner that the compressor diaphragm is arranged to be reciprocably driven by the motor. The pressure reservoir associated with the pneumatic pump is communicable with a control valve which is operable to selectively direct pressurized air to a main pneumatic line leading to a pneumatic timer or similar Patented June 13, 1961 control device. The control valve is arranged to close communication between the reservoir associated with the pneumatic pump and themain pneumatic line until the pressure within the reservoir has been built up to a predetermined level by reciprocation of the diaphragm within the pneumatic pump and is thereafter operable to open communication between the reservoir and the main pneumatic line to direct pressurized air to the pneumatic timer within the washing machine from whence it is subsequently directed to its point of utilization. In the embodiment of the invention illustrated in the drawings appended to this specification, a pressure regulator is shown as being situated within the main pneumatic line to maintain the pneumatic pressure in the line on the downstream side thereof at a preselected maximum.

The atmospheric inlet to the pneumatic pump has a check valve associated therewith which is operable to permit unidirectional air flow into the compression chamber of the pump which, in turn, has an air operated valve associated therewith which is elfective to close communication between the atmosphere and the compression chamber of the pneumatic pump. A second check valve is also seated within the pneumatic pump which is etfective to permit unidirectional air flow from the compression chamber of the pump into the pressure reservoir. When the check valve at the inlet to the pump is closed, upward movement of the diaphragm within the pneumatic pump will elfect compression of the air within the compression chamber to force the same through the second mentioned check valve and into the reservoir but a vacuum will be created within the compression chamber to thereby hold the diaphragm in its compressionstroke position to thereby inactivate the diaphragm thus releasing the pneumatic pump load from the main washing machine motor.

The control valve which forms a part of the present invention comprises generally a valve body having upper and lower diaphragm chambers therein and having a cylinder therein which has an inlet and a pair of outlets opening thereto. Flexible diaphragms extend across each of the diaphragm chambers and are centrally connected to a motion translation rod which, in turn, is operably associated with a spool valve in the cylinder of the valve body to efiect reciprocable movement thereof. One of the outlets from the cylinder is communicable with the lower diaphragm chamber on one side of the diaphragm therein while the second outlet from the cylinder is communicable with the main pneumatic line and the other diaphragm chamber on one side of the diaphragm disposed therein.

In a first position of the spool valve, one diaphragm chamber is communicable with pressurized air from the compressor reservoir so that the diaphragm therein is moved downwardly as the pneumatic pressure within the compressor reservoir increases. Downward movement of this diaphragm eifects movement of the spool valve within its respective cylinder until the spool valve has been moved to a position to close communication between the oompressor reservoir and that diaphragm chamber and to substantially simultaneously open communication between the compressor reservoir and the second outlet from the cylinder. Upon opening of communication between the compressor reservoir and the second of the outlets from the cylinder, pressurized air is communicated to the other of the two diaphragm chambers to hold the spool valve in a stationary position and, at the same time, pressurized air is directed from the second outlet to the main pneumatic line.

When pressurized air is directed to the main pneumatic line, air is directed to the air operated valve associated with the inlet check valve in the pneumatic pump and the inlet to the pneumatic pump is closed and the pneumatic pump is uncoupled from the motor in the manner which has hereinbefore been described. Thus, the pneumatic pump is inactivated until the pneumatic pressure within the main fluid line and the compressor reservoir has been reduced sufficiently to the point wherein a biasing member associated with one of the diaphragms will move each of the diaphragms and the motion translation rod associated therewith in a direction to vent the main pneumatic line to the atmosphere and effect opening of the inlet to the pneumatic pump to initiate another pump operating cycle.

An electrical switch is also associated with the pneumatic relay system to control the energization of various electrical components in the washing machine such as, for instance, the pneumatic timer mechanism, and is so arranged that the switch is closed to energize the various electrical components only during those intervals when the pneumatic pump is inactivated and so that upon activation of the pump by the main washing machine motor, the electrical contacts in the switch are opened to deenergize the electrical components associated therewith.

Accordingly, it is a principal object of the present invention to provide a pneumatic relay system particularly adapted to control the pneumatic and electrical actuation of various components in a washing machine.

A further object of the present invention is to provide a pneumatic relay system having a pneumatic pump associated therewith which is intermittently driven by the main washing machine motor only during those intervals when little or no machine load is applied to the motor.

A still further object of the invention is to provide a control valve associated with a pneumatic relay system of the type herein described which is operable to close communication between the compressor reservoir associated with the pneumatic pump and the main pneumatic line until a predetermined fluid pressure has been built up within the compressor reservoir and to thereafter open communication therebetween until the pneumatic pressure within the compressor reservoir has been reduced to a predetermined level.

These and other objects of the invention will appear from time to time as the following specification proceeds, and with reference to the accompanying drawings, wherein:

FIGURE 1 is a view of a pneumatic relay system constructed in accordance with the principles of the present invention and showing some parts diagrammatically, others in side elevation, and still others in vertical section;

FIGURE 2 is a vertical sectional view through a control valve constructed in accordance with the principles of the present invention and showing the diaphragms and spool valve therein in a first position;

FIGURE 3 is a fragmental vertical sectional view of the control valve illustrated in FIGURE 2 but showing the spool valve in a second position;

FIGURE 4 is a vertical sectional view through a check valve which is utilized in the illustrated embodiment of the present invention; and

FIGURE 5 is another vertical sectional view through the check valve illustrated in FIGURE 4 but taken on a plane perpendicular to that of FIGURE 4.

In the embodiment of the invention illustrated in the drawings, there is shown diagrammatically a main washing machine motor which is operatively associated with a pneumatic pump 11 to drive the same. The pneumatic pump includes generally a compressor 12 and a compressor reservoir 13.

A pneumatic control valve 14 is associated with the compressor reservoir 13 and is adapted to controllably direct pressurized air from the compressor reservoir 13 to a main pneumatic line 15. The main pneumatic line 15 has a pressure regulator 16 associated therewith which is adapted to maintain a constant maximum pressure on the downstream side thereof within the pneumatic lines but which, it should be noted, is not an essential element in the pneumatic relay system which forms the subject of the present invention. A branch pneumatic line 17 leads from the main pneumatic line, on the downstream side of the pressure regulator 16, to the compressor 12 to control the operation of the compressor in a manner which will hereinafter be more fully described in detail.

The compressor 12 comprises generally a valve block 20 to which a reservoir housing 21 is sealed by means of a gasket 22. The reservoir housing 21 may be secured to the block 20 in any suitable manner. An inlet port 23 is formed within the valve block in communication with the line 17 while an outlet port 24 is formed therein in communication with the interior of the reservoir housing 21.

A compression chamber 25 is formed and defined by a recessed portion in the bottom of the valve block 20 and by a flexible diaphragm 28 which extends thereacross. Preferably the diaphragm 28 has an outer annular raised bead 29 which is seated in a mating groove 30 formed in the valve block 20.

The diaphragm 28 may be made out of rubber or any one of the known substitutes therefor and is provided with a reenforced central portion which is formed with an annular disk 31 held on the underside thereof by means of a depending lip 32 of the diaphragm 28.

A base plate or cap 33 extends over the diaphragm member 28 and retains the marginal edge thereof seated against the valve block 20. The base plate 33 includes a cup portion 34 and a hollow stem portion 35 which receives a reciprocable power shaft 36. An air vent 37 is provided in the base plate 33 to keep the underside of the diaphragm 28 in communication with the atmosphere to prevent pressure buildup intermediate the diaphragm 28 and the base plate or cap 33.

The power shaft 36 is operatively connected at its upper end to the diaphragm 28 and at its lower end to a yoke 38 within which is mounted a pin 37a rotatably supporting a cam follower wheel 39. An annular disk 40 carried by the shaft 36 at its lower end portion provides a reaction means for a compression spring 41 which extends between the cap member 33 and the annular disk 40.

The wheel or roller 39 rides on a cam 45 formed on the upper surface 46 of a cam wheel 47. The cam wheel 47 is rotatably supported on an output power shaft 48 of the main washing machine motor 10 and is rotatably driven thereby.

-An outlet check valve 50 is seated within the outlet port 24 on an annular flange 51 formed integrally with the valve block 24] and is maintained in seating engagement therewith by means of a cylindrical ring 53 which frictionally engages the sidewall of the port 24. It will here be noted that the outlet check valve 50 is arranged to permit only unidirectional flow from the compression chamber 25 to the reservoir 21. Similarly, an inlet check valve 55 isseated within an enlarged diameter portion 56 of a fluid inlet passageway 57 which is arranged to provide fluid communication between the inlet port 23 and the compression chamber 25. It will further be noted that a flexible diaphragm 58 has a peripheral head 59 seated within an annular groove 60 formed Within the valve block 20 and that a valve member 61 is suitably centrally secured to the diaphragm 58 in coaxial alignment with the central passageway in the inlet check valve 55 to control fluid flow therethrough in a manner which will hereinafter become more fully apparent. The diaphragm 58 is normally urged to the position illustrated in FIGURE 1 by a spring 58a and is moved in an opposite direction by fluid pressure as will hereinafter be described.

The

check valves

50 and 55 are alike and each includes a valve body 62 formed of rubber or the like. The valve body 62 has a depending somewhat flattened hollow portion 63 which. is generally of rectangular cross-section. Member 63 has an elongated passageway 64 therein in communication with a central passageway 65 in direct alignment therewith. Disposed within the hollow portion 63 is a pin 66 which extends lengthwise thereof and which is snugly retained at opposite ends by the end walls of the portion 63. The sidewalls of the portion 63 in conjunction with pin 66 form a valve to restrict the passage of air through the unit. Pin 66 has its opposite ends rounded as at 67 where it engages the opposite ends of passageway 64 and slightly stretches the member forming that passageway. Two depending tongues 68 extend downwardly toward pin 66 and serve to properly locate pin 66..

Whenever the pressure around the outside of the elongated passageway member 63 is less than the air pressure at the inlet 70 of the check valve, the walls of the passageways 64 yieldably expand and spread apart to permit the movement of air past the pin 66 to the outlet 71 of the check valve. When, however, the pressure surrounding the elongated passageway portion 63 is greater than the air pressure at the inlet 70 of the check valve, the greater air pressure on the exterior of the passageway member 63 will collapse the walls 63 and prevent the passage of air past the pin 66.

It will thus become apparent that the valve member or plunger which is connected to the diaphragm 58 acts as a valve and is arranged to open and close the inlet 70 of the inlet check valve 55.

The operation of the pump is somewhat as follows: Assume, for illustrative purposes, that the cam wheel or roller 39 is resting on the cam wheel 47 at the beginning of the cycle of operation. As the cam wheel 47 is rotated, cam roller 39 will ride up onto the high portion of the cam 45 which, in turn, will force shaft 36 upwardly against the action of spring 41 and the diaphragm 28 will be moved upwardly into juxtaposition with the uppermost portion of the compression chamber 25. The spring member 41 will act to return the roller 39 to the level illustrated in FIGURE 1 upon further rotational movement of the cam wheel 47. Since the outlet check valve 50 will not permit the passage of air from the reservoir chamber to the compression chamber 25, a partial vacuum will be formed within the compression chamber causing the air on the inlet side of check valve '55 to expand the sidewalls of the check valve to open the air passageway into the compression chamber 25 and permit the flow of air thereto from the atmosphere. When the power shaft 36 and the diaphragm are again raised to their uppermost position by the cam 45, the increased pressure of air caused by the piston action of the upwardly moving diaphragm on the outer walls of the inlet check valve will be greater than the pressure on the inlet side of the valve 55, and the inlet check valve 55 will close. However, on the upstroke of the diaphragm the pressure at the inlet 70 of the outlet check valve 24 will be greater than the pressure surrounding the elongated passageway walls and thus air will pass through the valve from the compression chamber 25 to the reservoir 21.

Upon closure of the inlet check valve 55 by the valve member 61 associated with diaphragm 58, the diaphragm 28 will be rendered inoperative after moving through its compression stroke since a vacuum will be created above the diaphragm so that the air pressure acting upwardly on the diaphragm and communicated to the underside of the diaphragm through the vent port 37 will be sufficiently great to overcome the opposing biasing force of spring member 41. The diaphragm 28 will thus remain in its upper position so long as the inlet check valve 55 remains closed by valve member 61. Thus, even though the cam wheel 47 is rotating, the diaphragm will not be moved and no additional air will be forced into the accumulator chamber or reservoir 13. Accordingly, the load of driving the penumatic pump 11 will be released from the main motor 10.

Referring now particularly to FIGURES 2 and 3, of the drawings, the control valve 14 is shown as comprising generally a valve body 80 having a radially enlarged diaphragm chamber 81, a radially reduced diaphragm D chamber 82, and a cylinder 83 formed therein in coaxial alignment with one another.

Annular grooves

84 and 85 are formed about the

diaphragm chambers

81 and 82, respectively, within which are adapted to seat the beaded

peripheral portions

86 and 87 of a pair of

flexible diaphragms

88 and 89, respectively.

The

diaphragms

88 and 89 each have a stiifening plate 90 molded therein which, like the

diaphragms

88 and 89, are centrally apertured to receive a motion translation rod 91 therethrough. The motion translation rod 91 is adapted to extend through coaxially aligned apertures 93 in the several lateral walls of the valve body 80 and is suitably slidably sealed within each of the upper two apertures by means of O-rings 94 which are seated within suitable receiving grooves 96 within the wall portions of the valve body 80 defining each of the apertures.

A pair of resilient members 98 are afiixed to the motion translation rod 91 in spaced relation from one another within the cylinder 83 and form, with that portion of the motion translation rod 91 extending between the valve members 98, a spool valve 100 which is eifective to selectively communicate pressurized air from an inlet 101 to a pair of spaced

outlets

102 and 103 which are communicable with the interior of the cylinder 83. The

outlets

102 and 103 are defined by a pair of connecting

nipples

105 and 106, respectively, to which a pair of hoses or

tubes

107 and 108 are adapted to be connected. These hoses are, in turn, adapted to be connected to a pair of connecting

nipples

109 and 110 which have axial passages formed therein communicable with the interior of the

diaphragm chambers

82 and 81, respectively. Similarly, a hose or tube 99 communicates pressurized air from the reservoir 13 to the inlet 101.

It will also be noted that a T-member 112 is connected in the tube 108 to direct pressurized air from the outlet 106 to nipple 110 and to the main pneumatic line 15 which is connected to nipple 113 extending from and formed integrally with the T-member 112.

A spring member 115 is positioned in the diaphragm chamber 82 intermediate the lower wall thereof and the diaphragm 89 which serves to bias diaphragm 89 and consequently the motion translation rod 91 connected therewith, in an upward direction. Vent passages 117 and 117a are formed through the walls of the valve body 80 to communicate air within the

diaphragm chambers

81 and 82 on the opposite side of the diaphragms from the connecting

nipples

109 and 110 with the atmosphere to prevent pressure buildup on the undersurface of the diaphragms.

It will thus become apparent that when the diaphragms and motion translation rod are in the position illustrated in FIGURE 2, the spool valve 100 is effective to communicate pressurized air from the compressor reservoir 13 through the inlet 101 to the cylinder 83 and thence through the outlet 102 to the interior of the diaphragm chamber 82 above the surface of the flexible annular diaphragm 89. Air pressure will thus begin to build up within the diaphragm chamber 82 above the surface of diaphragm 89 until the fluid pressure therein is sufliciently built up to overcome the opposing biasing force of spring member 115 to eifect the compression of spring member 115 to thereby move the motion translation rod 91, diaphragm 89, diaphragm 88, and spool valve 100 downwardly. As the spool valve 100 moves downwardly within cylinder 83, the valve member 98 will be effective to close communication between the inlet 101 and the outlet 102 and valve member 98 will be effective to close communication between vent port 93 which opens to the lower end of cylinder 83, and the outlet 103 and to simultaneously open communication between inlet 101 and outlet 103. When pressurized air is thus communicated from the inlet 101 to the outlet 103, the pressurized air will be directed by the T-fitting 112 to the main pneumatic line 15 and will simultaneously be directed to the diaphragm chamber 81 on the upper surface of the diaphragm 88 through hose 108. Thus, because of the direct communication between the main pressure line on the upstream side of the pressure regulator 16 and the diaphragm chamber 81, the fluid pressure acting downwardly on diaphragm 88 will at all times remain equal to that within the fluid pressure reservior 13 and the main pneumatic line on the upstream side of the pressure regulator 16. As a result, the spool valve 1910 will be maintained in the position illustrated in FIGURE 3 until the fluid pressure within the main pneumatic line 15 on the upstream side of the pressure regulator 16 has been reduced to a point wherein the biasing force of spring member 115 tending to urge the diaphragrns 88 and 89 exceeds the fluid pressure force acting downwardly on the upper surface of diaphragm 88. When the fluid pressure within chamber 8 1 has thus been reduced to such a point, the spring member 115 will act to return the spool valve 1%, the

diaphragms

88 and 89, and the motion translation rod 91 to the initial position illustrated in FIGURE 2.

It will be understood that the diaphragm 88 is formed substantially larger than the diaphragm 89 so that it will act as a holding diaphragm to maintain the rod 91 in the position illustrated in FIGURE 3 until a relatively low pressure has been reached within the reservoir 13.

As shown most clearly in FIGURES 2 and 3, a bracket 120 is aflixed to the lower end of the cylinder 33 and has a depending portion 121 on which are mounted a pair of spaced electrical contacts 122 and 122a forming a switch 123. Contact 122 is suitably aflixed to the protruding portion of the motion translation rod 91 so that axial movement of the rod 91 will move the contact 122 relatively with respect to contact 122a to open and close an energizing circuit through the switch 123. As has hereinbefore been noted, various electrical components of the washing machine may be energized through the switch 125 so as to be electrically controlled as a function of the position of the motion translation rod 91 within the valve body 80.

As hereinbefore noted, the pressure regulator is not an essential element in the pneumatic relay system but functions to permit a higher reservoir pressure buildup when the cycle of operation is first initiated.

It will thus be understood that the pressure buildup in the compressor reservoir at the beginning of the cycle of operation of the washing machine will generally be sutlicient so that the complete cycle of operation of the washing machine can be completed without the necessity of again activating the compressor. As a result, the compressor pump will be activated to build up the pneumatic pressure within the compressor reservoir to the required level and will again be deactivated before the tub filling cycle has been completed so that the compressor pump will be inactivated before any substantial machine load is applied to the main washing machine motor.

The complete cycle of operation is somewhat as follows: Rotation of the cam wheel 47 acts to effect reciprocable movement of the power shaft 36 and the diaphragm 28 connected therewith to initiate a buildup of pressure within the compressor reservoir 13. Pressurized air within the ressrvoir 13 is communicated to the upper surface of diaphragm 8% within control valve 14 through the tube 99, cylinder 83, and tube 197. The diaphragm 89 remains unmoved until the pneumatic pressure within reservoir 13 and, consequently, within diaphragm chamber 82 on the upper surface of the diaphragm 89 overcomes the biasing force of spring member 115 acting to urge the diaphragm 89 upwardly within chamber 82. When the pneumatic pressure does reach this level, the diaphragm 89, and the motion translation rod 91 connected therewith will be moved downwardly until the diaphragms and spool valve have been moved to the position illustrated in FIGURE 3. When the spool valve 1110 is located in the position illustrated in FIGURE 3, pressurized. air from the reservoir 13 will be communicated to the main pneumatic line 15 through T-member 112 and to the diaphragm chamber 81 on the upper surface-of diaphragm 88. Due to the relatively large surface of the diaphragm 83, the motion translation rod 91 and consequently the spool valve 1110 will be maintained in the position illustrated in FIGURE 3 until the pneumatic pressure within themain pneumatic line 15 and the compressor reservoir 13 has been reduced to a relatively low level. At this latter predetermined pressure level, the biasing force of spring member 115 tending to urge the diaphragm 39 upwardly within the chamber 82 will overcome the fluid force of the pressurized air within chamber 81 acting downwardly on diaphragm 88 so that the diaphragrns and the spool valve will be returned to the position illustrated in FIGURE 2. In operation, the various parts of the control valve 14 will generally remain in the position illustrated in FIGURE 3 throughout the completion of the cycle of operation of the washing machine after they have initially been moved to this position at the beginning of the Washing machine cycle.

It will also be understood that when pressurized air from the compressor reservoir 13 is communicated to the undersurface of diaphragm 58 through the main pneumatic line 15 and the pneumatic branch line 17, the inlet check valve 55 to the compressor 12 will be closed and the power shaft 36 and diaphragm 28 will be maintained in their raised position at the end of their compression stroke so that the load applied to the motor 10, of driving compressor 12, will be released.

It will also be noted that when the motion translation rod 91 is in the position illustrated in FIGURE 2 that the movable contacts of switch 123 will be out of engagement with one another in an open circuit position so that the electrical components connected therewith will not be energized. Upon movement of the control rod 91 to the position illustrated in FIGURE 3, the

contacts

122 and 1220 will be moved into juxtaposition with one another so that an energizing circuit to the electrical components connected to the switch 123 will be closed.

Thus, both the pneumatic and electric machine load currents are activated at substantially the same time that the compressor load is released from the main washing machine motor.

If the air in the compressor reservoir 13 should drop to a predetermined level, then the pressure switch or control valve 14 will reset itself by the pressure differentials across the diaphragms so that the spool valve will be returned to the position illustrated in FIGURE 2. When the spool valve 100 is in the position illustrated in FIG- URE 2, the outlet 113 is vented to the atmosphere through the vent 93 so that there is a pressure at action across the upper surface of the diaphragm 58, thereby permitting the spring 58a to unseat the diaphragm valve from the inlet check valve 55 to permit air to be drawn into the pressurizing chamber 25.

It will herein be understood that this embodiment of the invention has been used for illustrative purposes only and that the pneumatic relay system herein described may find other uses than in association with washing machines, and that other objects and features of the present invention may be effected without departing from the spirit and scope of the novel concepts thereof.

I claim as my invention:

1. A pneumatic control valve comprising a valve body having first and second chambers and a cylinder formed therein in coaxial alignment with one another, a pair of outlets leading from said cylinder and spaced longitudinally along said cylinder, an inlet adapted to be connected to a source of pressurized air opening to said cylinder intermediate said outlets, movable wall members disposed within said chambers and peripherally sealed to the walls thereof, passages opening to said chambers so arranged that the direction of pressurized air thereinto will act to move said wall members in the same direction, means CQ lmunicating air from one of said outlets to one of said 9 passages, means communicating air from the other of said outlets to the other of said passages and to a point of utilization, a motion translation member disposed within said valve body concentrically of said chambers and said cylinder and extending therethrough and aflixed to each -of said wall members, a spool valve associated with said motion translation member and movable therewith disposed within said cylinder and operable to selectively communicate pressurized air from said inlet to one of said outlets.

2. A pneumatic control valve comprising a valve body having first and second chambers and a cylinder formed therein in coaxial alignment with one another, an inlet adapted to be connected to a source of pressurized air and a pair of spaced outlets opening to said cylinder, movable wall members disposed within said chambers and peripherally sealed to the Walls thereof, passages opening to said chambers so arranged that the direction of pressurized air thereinto will act to move said wall members in the same direction, means communicating air from one of said outlets to one of said passages, and means communicating air from the other of said outlets to the other of said passages and to a point of utilization, a motion translation member disposed within said valve body concentrically of said chambers and said cylinder and extending therethrough and aifixed to each of said wall members, a spool valve associated with said motion translation member and movable therewith disposed within said cylinder and operable to selectively communicate pressurized air from said inlet to one of said outlets.

3. A pneumatic control valve comprising a valve body having first and second chambers and a cylinder formed therein in coaxial alignment with one another, an inlet adapted to be connected to a source of pressurized air and a pair of spaced outlets opening to said cylinder, movable wall members disposed within said chambers and peripherally sealed to the walls thereof, the relative size of one of said chambers and the movable wall member diposed therein being substantially greater than that of the other of said chambers and the movable wall member disposed therein, passages opening to said chambers so arranged that the direction of pressurized air thereinto will act to move said diaphragms in the same direction, means communicating air from one of said outlets to one of said passages opening to said relatively smaller chamber, spring means within said relatively smaller chamber interposed between a wall portion of said valve body and the movable Wall member within that chamber on the opposite side of said movable wall member from the passage leading into that chamber, and means communicating air from the other of said outlets to another of said passages opening to said relatively larger chamber and to a point of utilization, a motion translation member disposed within said valve body concentrically of said chambers and said cylinder and extending therethrough and affixed to each of said wall members, and a spool valve associated with said motion translation member and movable therewith disposed within said cylinder and operable to selectively communicate pressurized air from said inlet to one of said outlets.

4. A pneumatic control valve comprising a valve body having first and second chambers and a cylinder formed therein in coaxial alignment with one another, an inlet adapted to be connected to a source of pressurized air and a pair of spaced outlets opening to said cylinder,

movable wall members disposed within said chambers and peripherally sealed to the walls thereof, passages opening to said chamber so arranged that the direction of pressurized air thereinto will act to move said wall members in one direction, spring means interposed between a wall portion of said valve body and one of said wall mern bers tending to move that diaphragm in an opposite direction, means communicating air from one of said outlets to one of said passages, and means communicating air from the other of said outlets to the other of said passages and to a point of utilization, a motion translation member disposed within said valve body concentrically of said chambers and said cylinder and extending therethrough and affixed to each of said wall members, and a spool valve associated with said motion translation member and movable therewith disposed within said cylinder and operable to selectively communicate pressurized air from said inlet to one of said outlets.

5. A pneumatic control valve comprising a valve body having first and second chambers and a cylinder formed therein in coaxial alignment with one another, a pair of outlets leading from said cylinder and spaced longitudinally along said cylinder, an inlet adapted to be connected to a source of pressurized air opening to said cylinder intermediate said outlets, movable wall members disposed within said chambers and peripherally sealed to the walls thereof, passages opening to said chambers so arranged that the direction of pressurized air thereinto will act to move said wall members in the same direction, means communicating air from one of said outlets to one of said passages, means communicating air from the other of said outlets to the other of said passages and to a point of utilization, a motion translation member disposed within said valve body concentrically of said chambers and said cylinder and extending therethrough and aflixed to each of said wall members, a valve member associated with said motion translation member and movable therewith disposed within said cylinder and operable to selectively communicate pressurized air from said inlet to one of said outlets.

6. A pneumatic control valve comprising a valve body 7 having first and second chambers and a cylinder formed therein in coaxial alignment with one another, an inlet adapted to be connected to a source of pressurized air and a pair of spaced outlets opening to said cylinder, movable wall members disposed within said chambers and peripherally sealed to the walls thereof, passages opening to said chambers so arranged that the direction of pressurized air thereinto will act to move said wall members in the same direction, means communicating air from one of said outlets to one of said passages, and means communicating air from the other of said outlets to the other of said passages and to a point of utilization, a motion translation member disposed within said valve body concentrically of said chambers and said cylinder and extending therethrough and afiixed to each of said wall members, a valve member associated with said motion translation member and movable therewith disposed within said cylinder and operable to selectively communicate pressurized air from said inlet to one of said outlets.

References Cited in the file of this patent UNITED STATES PATENTS