US3561325A

US3561325A - Reciprocating motor

Info

Publication number: US3561325A
Application number: US793686*A
Authority: US
Inventors: Charles P Lamb; William A Dudley
Original assignee: MERLA Inc
Current assignee: MERLA Inc
Priority date: 1969-01-24
Filing date: 1969-01-24
Publication date: 1971-02-09
Anticipated expiration: 1988-02-09

Abstract

This patent discloses an infection pump and a motor therefor. The pump proper is of the poppet valve type. The motor is a pneumatic diaphragm-operated motor. The control for the motor includes a pilot controlled by a pressure regulator and valves for controlling the rate of flow of fluid to and from the pilot. The pilot effects cycling of the motor by the action of mechanical relays in the pilot.

Description

United States Patent Inventors Charles P. Lamb;

William A. Dudley, Dallas County, Tex. App]. No 793,686 Filed Jan. 24, 1969 Patented Feb. 9, 1971 Assignee Merla, Inc.

Garland, Tex. a corporation of California RECIPROCATIN G MOTOR 11 Claims, 7 Drawing Figs.

U.S. Cl 91/335, 9l/341,9l/350,91/469 Int. Cl F011 23/00, F011 15/ 14 Field ot'Search 91/341, 350, 469, 335

A a a 47 a [56] References Cited UNITED STATES PATENTS 2,080,695 5/1937 Cargile 91/341 2,120,992 6/1938 Seiden 91/341 2,630,181 3/1953 Solum 91/341 2,833,219 5/1958 Lewis 91/341 3,082,596 7/1963 McGay et a1. 91/341 k .25 /9 a, f i394 \J/Vl 1 J RECIPROCATING MOTOR This patent relates to injection pumps and to a motor for operating the pump.

In order to obtain a wide range of volumetric capacity of an injection pump, it has been necessary in the past to use a plurality of pump plungers. For instance, in one well-known pump three pump plunger sizes are utilized to obtain a ratio of a little over 400 to l Simple pumps are also limited in the discharge pressure which they may operate against. The conventional pump utilizing trip valves has line pressure losses on both the intake and exhaust controls which limits the volume which can be delivered at high pressure.

An object of this invention is to provide 'a simple injection pump and motor therefor which can deliver a volumetric ratio of fluid of over 400 to l with a single plunger size.

Another object is to provide a pump and motor therefor which can operate with a discharge pressure much greater than pumps of comparable complexity and cost.

Another object is to provide an injection pump and motor therefor in which the stroke is automatically increased with increases in back pressure against which the pump is operating.

Another object is to provide an injection pump and motor therefor in which a single adjustment of the pump will set it to deliver from a fraction of a gallon to over a 100 gallons per day.

Another object is to provide an injection pump and motor therefor in which maximum control pressure may be delivered to the motor to overcome stalling of the motor due to a sudden increase in pressure pumped against to render the pump stall free up to the maximum pressure against which the pump can operate.

Another object is to provide an injection pump and a motor therefor in which the ratio of volume delivered per unit of time may be in excess of 400 to l utilizing a single plunger size in the pump.

Another object is to provide an injection pump and a motor therefor in which the discharge pressure of the pump may be substantially greater than comparable pumps with the same complexity of design and cost of manufacture.

Another object is to provide a pump and motor therefor which utilizes a much shorter stroke than conventional pumps for low volumes and therefore can utilize more open control valves to prevent clogging and utilize only a single plunger size for a large range of fluid delivery.

Another object is to provide a pump and motor therefor in which the line pressure losses normally experienced in conventional trip valve pumps are eliminated both on the intake and exhaust sides to permit the pump to deliver more volume at high pressures.

Other objects, features and advantages of the invention will be apparent from the drawings, the specification and the claims.

In the drawings, wherein illustrative embodiments of this invention are shown, and wherein like parts are referred to by like reference numerals:

FIG. 1 is a diagrammatic illustration of an injection pump constructed in accordance with this invention;

FIG. 2 is a view in cross section through the pilot and motor section of the pump of FIG. 1;

FIGS. 3, 4, 5 and 6 are schematic cross-sectional views indicating successive steps of the operation of the pilot and motor of this invention; and

FIG. 7 is a view of a modified form of this invention.

This invention was developed in conjunction with a chemical injector pump such as shown in FIG. 1, but it will be apparent that the motor and pilot therefor can be utilized in any situation in which it is desired to reciprocate a rod as, for instance, in a sampling device.

In FIG. 1, the conventional injector pump is illustrated. This includes the pump proper indicated generally at 10 which has the usual inlet and outlet check valves permitting flow into and out of the pump but not in reverse direction, and a plunger 11 which reciprocates in the chamber to alternately draw fluid into the chamber on the retraction stroke and to force fluid from the chamber on forward movement of the plunger into the pump chamber.

The plunger 11 is reciprocated by a pneumatic motor. The motor includes the two mating housing halves l2 and 13 suitably secured together by ring clamp 14. A diaphragm I5 is clamped between the two housing halves and provides the pressure responsive member to reciprocate the plunger 11 in response to the effect of fluid pressure in the chamber 16 defined by the housing 13 and diaphragm 15. The counteraction of the return spring 17 and back pressure against which the pump 10 is operating will move the plunger 11 to its retracted position.

The motor is reciprocated by action of the pilot indicated generally at 18.

Fluid pressure for operating the pilot is provided from source 24 to the regulator valve indicated generally at 25. The regulator valve 25 may be any conventional form of valve for regulating pressure downstream of the valve. The pressure fluid passes from the regulator through conduit 26 to the pilot. Avalve 27 is provided in conduit 26 for controlling the rate of flow of fluid to the pilot. Fluid leaves the pilot through the outlet valve 28 which is adjusted to control the rate of flow of fluid from the pilot.

The pilot housing is provided by a boss 19 on the motor housing 13, a sub or housing 21 and a cap 22. The sub 21 and cap 22 are secured to the boss 19 by a plurality of suitable screws, one of which is shown at 23. Suitable seals '(not shown) are provided between the sub, boss and cap.

An inlet valve is provided for controlling flow from the conduit 26 into the pilot. In the illustrative form the sub 18 has a passageway 29 connecting one face 31 of the sub with the interior of the sub. The face 31 has an O-ring 32 therein which cooperates with the inlet valve member 33 to control flow through the passageway 29. The inlet valve 33 is carried on a valve stem 34 which reciprocates within a suitable bushing 35. An O-ring 36 prevents flow of fluid between the bushing and valve stem. Thus with reciprocation of the valve stem 34, the inlet valve opens and closes to control flow of fluid through a passageway 29 into the interior of the pilot.

Flow of fluid from the pilot is controlled by an outlet valve. Within the sub 18 an outlet valve seat 37 is provided. A suitable O-ring 38 in the seat cooperates with outlet valve member 39 to control flow through the outlet passage 41. While the inlet and outlet valves could be controlled by a separate mechanism, it is preferred that they be controlled by a single mechanism to open and close alternatively. For this purpose, the valve stem 34 of the inlet valve is connected to or forms a part of the outlet valve member 39. As the two valve seats 31 and 37 face in opposite directions, and the stem 34 is of slightly greater length than the distance between the two seats, the valve members will seat and unseat alternatively with reciprocation of the valve stem 34.

Means are provided between the pressure responsive member provided by the diaphragm 15 of the motor and the inlet and outlet valves for alternatively opening the inlet valve against the force of inlet pressure on movement of the pressure responsive member in a direction to reduce the size of the chamber 16 and to open the outlet valve against the force of the chamber pressure on movement of the pressure responsive member 15 in a direction to expand the volume of the chamber. With either valve closed there is a differential across the closed valve tending to hold it closed until such time as the diaphragm has moved to a position where sufficient force is exerted on the valve stem 34 to shift the two valve members between open and closed positions.

In accordance with this invention, the means for shifting the valve member includes a resilient differential member such as spring 42, so that the length of the stroke will automatically be varied in accordance with the amount of pressure fed into chamber 16. Thus the combination of the regulator valve to regulate the amount of pressure available to chamber 16 and the use of the inlet and

outlet control valves

27 and 28 to control the rate at which pressure is fed into and out of chamber 16, permits control of cycles per minute and length of stroke of the motor. It will be apparent that a pair of springs could be used, one being compressed when the diaphragm moves toward injecting position to close the inlet valve when the diaphragm has moved far enough to unseat the outlet valve against chamber pressure and another being compressed upon movement of the diaphragm to withdraw the plunger a sufficient distance to build up enough spring pressure to unseat the inlet valve against the force of pressure within the dome chamber 43.

In accordance with this invention, it is preferred that a pair of mechanical relays be utilized which will permit the use of a single spring which is compressed in both directions of movement of the diaphragm to unseat the valves upon the building up of sufficient force to overcome the pressure differential thereacross. The spring 42 is contained within a first outer relay 44 having an inturned flange 44a on its end adjacent the diaphragm 15 and an out-tumed flange 44b on its end remote from the diaphragm 15 The interior wall of the relay acts as a spring guide. The outer relay has a lost motion connection with the shell 45 which is secured to the outlet valve member 39. The free end of the shell 45 has an inturned flange 46 spaced some distance from the boss 39a on the valve member 39. The boss is spaced some distance from the inturned flange 46 on the shell so that the first outer relay is free to reciprocate between the boss and the inturned flange 46 of the shell.

Internally of the spring 42 a second inner relay 47 is provided. This inner relay also acts as a spring guide. As in the case of the outer relay, an inturned flange 47a is provided on the end adjacent the diaphragm 15 and an out-turned flange 47b is provided on the end remote from the diaphragm. A stem 48 having a head 48a thereon extends through the inner relay. As the inturned flange 47a is some distance remote from the valve member 39, the head 48a has a lost motion connection with the internal relay.

Reference is now made to FIGS. 3 through 6 which show in successive stages the operation of the pilot. In FIG. 3 the pilot is shown with the plunger 11 fully retracted and the inlet valve member 3.2 in open position. As pneumatic fluid is fed into chamber 16, the force against the diaphragm 15 builds up and begins to move the diaphragm 15 to the left of the drawing against the force of the return spring 17 and the pressure being pumped against. As the spring 42 is under compression, movement of the diaphragm 15 to the left will permit expansion of the spring 42 to move the outer relay 44 to the left. Such movement will continue until the outer relay 44 engages the shell flange 46. At approximately the same time, the head 48a of the stem 48 engages the inturned flange 47a of the inner relay 47. This position is shown in FIG. 4. Further movement of the diaphragm to the left will result in movement of the inner relay to compress the spring 42 and urge the outer relay shell and both valve members to the left as shown in FIG. 5.

All during the time of the movement of the diaphragm to the left, the pressure within the chamber 16 has been building up. Thus a substantial force is exerted against the outlet valve to hold the outlet valve on its seat. The downstream side of the outlet valve will be subjected to substantially atmospheric pressure as the outlet control valve 28 vents directly to atmosphere. With high regulator pressure the diaphragm will move to the left a greater distance than with low regulator pressure before the force of the differential across the outlet valve is overcome. Once the force exerted by spring 42 exceeds the force of the differential across the outlet valve, the outlet valve will be unseated. As the differential rapidly reduces as pressure flows past the outlet valve, the force of the spring will snap the outlet valve to full open position and snap the inlet valve to full closed position.

Once the force of the outlet pressure differential across the outlet valve is overcome and the valve snaps to outlet valve open-inlet valve closed position, the diaphragm begins its movement to the right of the drawings under the force of the return spring 17 and the pressure being pumped against. FIG. 6 shows the diaphragm in its partially returned position. As the diaphragm begins its return stroke, the spring 42 being compressed will first expand to move the inner relay into engagement with the outlet valve member. Continued movement of the diaphragm will cause it to engage the outer relay as shown in FIG. 6. Further movement of the diaphragm to the right will then commence compression of spring 42. Compression will continue to be built up in the spring 42 under the force of the return spring 17 and the pressure being pumped against until the force exerted by the spring exceeds the force of the differential across the inlet valve member 33. The force in the chamber at this time will be substantially atmospheric and the differential to be overcome can thus be controlled by the regulator pressure. Again, a high regulator pressure requires more movement of the diaphragm to the right before the inlet valve is unseated as compared with a low regulator pressure. Once inlet valve 33 is unseated, pressure rapidly begins to equalize across the valve member and it is snapped to open position.

From the above explanation, it will be seen that the cycle time and length of stroke of the pilot may be readily controlled by fine adjustment of the inlet and outlet valves and by regulating the pressure utilized to operate the pilot. As the pressure is increased, the length of the stroke of the plunger 11 will be increased. The degree of opening of the inlet valve will determine the time necessary for the plunger to move to the left in a direction to expand the volume of the chamber 16 until the plunger completes its stroke. The degree of opening of the outlet valve will determine the rate of movement of the diaphragm to the right in a direction to contract the volume of chamber 16 and control the return cycle time. Thus three simple adjustments give complete control of operation of the pilot and the pump.

In F IG. 7, a modified form of this invention is disclosed having two additional features. The first feature is a connection of the spring chamber of the regulator valve with the chamber 16 of the motor. This permits the motor and regulator to take into account high back pressures being pumped against, as will be explained more fully hereinafter. The other feature is the use of a single adjustment for regulator pressure and the inlet and outlet valve. The motor and pilot are identical with the motor and pilot shown in FIG. 2.

The regulator indicated generally at 51 is conventional in form except that the spring housing 52 is tapped and a fitting 53 extends through the wall of the housing.

In order that the fluid pressure in the motor chamber 16 be effective on the diaphragm 54 of the regulator 51, a conduit 55 extends from fitting 53 to a fitting 56 which is carried in a boss 57 on the motor housing 13. It will be noted that the fittings 53 and 57 have a fairly small diameter so that a finite period of time will be required for pressure to pass from the motor housing to the spring housing of the regulator. Thus, where the motor is operating at a rapid rate, the pressure within the motor housing will have very little effect upon the regulator. On the other hand, when the rate is slow, the pressure within the motor housing will be a factor in the pressure being maintained in the pilot and motor by the regulator 51.

To provide for a single adjusting means for the regulator valve and the inlet and outlet control valves, a valve housing 58 is provided which is secured to the regulator spring housing 52 by suitable threaded connection 59. The inlet to the pilot is connected to the valve housing 58 through a suitable tube 61. In like manner, the outlet from the pilot is connected to the valve housing 58 through a suitable tube 62. These tubes 61 and 62 are indicated schematically in that fittings are omitted to conserve space in the drawing.

An adjusting stem 63 extends through the regulator valve housing 52 and has a threaded connection therewith. This stem bears upon the regulator spring 64. A suitable knurled knob 65 is provided at the other end of the stem 63 and rotation of the knob will change the setting of the spring 64.

Also carried by the stem 63 is an annular valve needle 66. This needle has a bore 66a extending therethrough and is threadedly connected to the stem 63 through the thread system 67 The annular valve needle carries a frustoconical valve member 68 which cooperates with a valve seat 69 in the valve housing to control flow of inlet fluid pressure to the pilot. At the other end of the annular valve needle another frustoconical valve member 71 is provided which cooperates with valve seat 72 to control flow of fluid from the pilot. lnterrnediate these two valve members, the annular needle valve is provided with an O-ring 73 which cooperates with bore 74 in the valve housing to separate inlet and outlet pressure fluids.

The valve seat 72 communicates with the exterior of the valve housing. The valve seat 69 communicates through the conduit 75 with the outlet of the regulator valve.

in operation, fluid from a suitable source, not shown, is fed into the inlet 76 of the regulator valve. This fluid passes to the valve proper of the regulator valve and is present at the seat 77. The valve member 78 is urged by spring 79 against seat 77. Spring 79 urges the valve member 78 toward its seat against the force of inlet pressure fluid.

The diaphragm 54 carries a stem or extension 81 which is engageable with the valve member 78. Thus the force of spring 64 on the diaphragm tends to urge the extension 81 against the valve member 78 to unseat the valve member and permit fluid to flow through the regulator. When the back pressure against the diaphragm is sufficient to overcome the force urging the diaphragm toward valve opening position, then the extension 81 is moved out of contact with the valve member 78 to permit it to close.

Pressure fluid flows from the regulator 51 through conduit 75 into the valve body 58. The incoming fluid flows past the valve member 66, and out of the valve body through the conduit 61 to the pilot.

Fluid passes through the pilot in the way previously explained, and then out through conduit 62 past valve member 71 to atmosphere.

As the two inlet and outlet valve members are carried on a single unitized valve, they will be simultaneously adjusted by rotation of the knob 65.

As the needle valve 66 is locked in position on shaft 63 by a pin 82 which extends through the needle valve and shaft 63, rotation of the knurled handle 65 will move the two valve members relative to their seat at the same time that the compression on the spring 64 of the regulator valve is changed. The system iscalibrated by removing pin 82 and, with the regulator spring 64 set for a desired pressure, the needle valve member 66 is rotated along the stem 63 until the two valve surfaces 68 and 71 engage their respective seats. The pin 82 is then inserted through the valve 66 and stem 63 to lock the system in. Thereafter rotation of the knurled knob 65 will determine the degree of compression of spring 64 and the opening of the inlet and outlet valves.

When it is desired to deliver a minimum volume of fluid at a low discharge pressure, the knurled knob 65 is screwed in a small amount. The valves 69 and 71 are barely opened to give restricted flow from the regulator to the pilot and restricted from the pilot to the atmosphere. The regulator pressure is low because the regulator spring has very little force. As the pressure delivered to the pilot is low, only a short, slow stroke to the right of the diaphragm is needed to snap the pilot inlet valve off. its seat. As there is light resistance to inserting the plunger into the pump, only small motor pressure is required to move the pump to the left. As the pressure within the chamber 16 is not high, very little spring force is required to snap the exhaust valve off its seat. The feedback through conduit 55 is relatively ineffective at low pressures. Thus at low discharge pressures, minimum volume is delivered by a short, slow St oke-to both the left and right of the diaphragm.

When it is desired to deliver a maximum volume at a low discharge pressure, the calibrated control handle is screwed in a maximum amount. The valves 69 and 71 are thus wide open, giving unrestricted flow from the regulator to the pilot, and

unrestricted flow from the pilot to the atmosphere. The regulator pressure is high because the regulator spring has maximum force. This results in high pressure against the inlet valve. As the needle valves are wide open, the pressure within the motor chamber builds up and dissipates rapidly and a quick maximum stroke results to provide the heavy spring forces necessary to snap the inlet valve off its seat. As little pump resistance is encountered, there is little pilot pressure required to move the pump plunger into the pump. As the movement is rapid, pressure does not have time to build up in the motor chamber and very little spring force is required to snap the exhaust valve off its seat. Therefore, the stroke to the left is short and quick because of the high regulator pressure available. Feedback to the regulator is relatively ineffective because the stroke to the left is over before substantial pressure can be delivered to the regulator spring chamber.

When it is desired to deliver a minimum volume at a maximum discharge pressure, the control knob is screwed in a small amount and the needles are barely open, giving restricted flow from the regulator to the pilot and from the pilot to atmosphere. However, the regulator pressure is high in spite of the minimum spring force because of the residual pressure trapped between the regulator valve and the closed intake pilot seat at the beginning of the pilot exhaust cycle. This results in a long, slow retraction stroke of the plunger. High pump pressures are encountered as we are pumping against a maximum back pressure. Thus, maximum pilot pressure is required. The regulator spring setting is undesirably low. To compensate, subadequate pilot pressure in the motor diaphragm section is delivered to the control spring side of the regulator diaphragm. This boost will slowly, by way of the restricted pilot circuit, make available to the motor diaphragm any pressure required to overcome the pump. Thus, the pressure within the chamber 16 slowly builds up and a maximum spring force is required to snap the exhaust valve off its seat. This results in a long, slow stroke to the left. As noted before, the maximum pressure have built up between the regulator valve and the intake valve 33, and thus maximum force is required to snap the intake valve from its seat.

When it is desired to deliver maximum volume against a maximum back pressure, the control handle is screwed in a maximum amount, giving unrestricted flow from the regulator to the pilot and from the pilot to atmosphere. The regulator spring is at a maximum. Thus, heavy force must'be applied by the spring to snap the inlet valve off its seat against the heavy regulator pressure. It results that the stroke to the right will be long and rapid. This is because the heavy back pressure and the return spring are acting on the diaphragm and the outlet needle valve 71 is wide open to permit the motor chamber to be emptied of pressure fluid rapidly. As a maximum pump load is encountered, a maximum pilot pressure is required to insert the plunger into the pump. Thus, the pressure will build up in the pump chamber and maximum spring force will be required to snap the exhaust valve off its seat. Therefore, the stroke to the left will be long and rapid.

It will be apparent that the feedback circuit prevents any possibility of the pump stalling under any conditions, as a buildup of pressure in the pump chamber is reflected in the regulator. spring chamber to open the regulator valve and provide additional pressure to overcome any unexpected stall conditions.

By way of example, if it is desired to deliver a small volume of fluid at an intermediate pressure, the control handle would be screwed in a small amount. The regulator spring might well not provide the necessary pressure, but the extra pressure will be supplied by the regulator automatically as when the pilot pressure is unable to move the motor diaphragm the pressure against the diaphragm is fed to the regulator spring side of the regulator diaphragm to boost the regulator pressure, and eventually sufiicient pressure will be developed against the motor diaphragm to move the pump piston against the pressure. If we assume that there is a sudden increase in pressure of fluid being pumped against so that additional pressure is necessary, the system will slowly boost the pilot pressure as the pressure increases in the motor chamber and is fed back into the spring chamber to the pressure necessary to deliver approximately the same amount of fluid without any adjustment of the system.

It will be appreciated that the feedback connection between the motor chamber and the regulator chamber may be utilized without the simultaneous adjusting feature shown in FIG. 7.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

We claim:

1. A pneumatic motor for reciprocating a member comprising:

a chamber including a pressure responsive member as a wall thereof;

means urging the pressure responsive member in a direction to contract the chamber;

an inlet into said chamber;

a valve seat and valve member controlling flow through said inlet, said inlet valve member having a pressure responsive surface exposed to upstream pressure;

an outlet from said chamber;

a valve seat and valve member controlling flow through said outlet, said outlet valve member having a pressure responsive surface exposed to pressure within said chamber; means including resilient means between said pressure responsive member and said inlet and outlet valves for alternatively opening said inlet valve against the force of inlet pressure on movement of the pressure responsive member in a direction contracting said chamber and opening said outlet valve against the force of chamber pressure on movement of the pressure responsive member in a direction to expand said chamber;

a regulator valve controlling pressure of gas supplied to said inlet,

said regulator valve including a spring chamber having a spring therein urging the pressure responsive member of the regulator valve toward valve opening position; and

a conduit connecting said chamber of the motor to said spring chamber.

2. The motor of claim 1 in combination with valve means regulating flow to and from said chamber inlet and outlet respectively, and wherein a single adjustment controls said valve means and the setting of said regulator valve.

3. The motor of claim 1 in combination with valve means regulating flow to and from said chamber inlet and outlet respectively, wherein a single adjustment controls said valve means and the setting of said regulator valve, and a fluid handling apparatus having a reciprocating member connected to said pressure responsive member of the motor.

4. Apparatus comprising:

a fluid handling device having a reciprocating member;

a pneumatic motor having a chamber including a pressure responsive member as one wall thereof;

means connecting the reciprocating member to said pressure responsive member;

an inlet into said chamber;

inlet valve means controlling flow through said inlet;

an outlet from said chamber;

outlet valve means controlling flow through said outlet;

means responsive to reciprocation ofsaid reciprocating member for alternatively opening and closing said inlet and outlet valve means;

a regulator valvecontrolling pressure of fluid to said inlet;

valve means controlling flow of fluids to and from said inlet and outlet; and

conduit means between said chamber and the regulator valve spring chamber whereby pressure in the motor chamber affects operation of the regulator valve.

5. The apparatus of claim 4 wherein a single adjustment controls the setting of the regulator valve and said valve means controlling flow of fluids to and from said inlet and outlet.

6. A pneumatic motor for reciprocating a member comprismg:

a chamber including a pressure responsive member as a wall thereof;

an inlet into said chamber;

an outlet from said chamber;

a valve seat and valve member controlling flow through said outlet, said outlet valve member having a pressure responsive surface exposed to pressure within said chamber;

shell means attached to said inlet and outlet valve members and alternatively seating and unseating said inlet and outlet valve members with movement of said shell means;

a first relay having a lost motion connection with said shell means;

a second relay reciprocal relative to said shell means and first relay;

a lost motion connection means between said pressure responsive member and said second relay;

resilient means between said first and second relays; and

means regulating the pressure of gas supplied to said inlet.

7. The motor of claim 6 in combination with valve means regulating flow to and from said chamber inlet and outlet respectively.

8. A pneumatic motor for reciprocating a member comprismg:

a chamber including a pressure responsive member as a wall thereof;

an inlet into said chamber;

a valve seat and valve member controlling flo'Wthrough said inlet, said inlet valve member having a pressure responsive surface exposed to upstream pressure;

an outlet from said chamber;

a valve seat and valve member controlling flow through said outlet, I said outlet valve member having a pressure responsive surface exposed to pressure within said chamber; shell means attached to said inlet and outlet valve members and alternatively seating and unseating said inlet and outlet valve members with movement of said shell means;

double lost motion connection means between said shell means and said pressure responsive member;

resilient means urging each of said lost motion connection.

means toward extended position; and

means regulating the pressure of gas supplied to said inlet;

9. The motor of claim 8 in combination with valve means regulating flow to and from said chamber inlet and outlet respectively and a fluid handling apparatus having a reciprocating member connected to said pressure responsive member.

10. A pneumatic motor for reciprocating a member comprising;

a chamber including a pressure responsive member as a wall -thereof;

an inlet into said chamber;

a valve seat and valve member controlling flow through said inlet,

a lost motion connection means between said shell means and pressure responsive member; resilient means urging said lost motion connection means toward its extended position; and means regulating the pressure of gas supplied to said inlet. 11. The motor of claim 10 in combination with valve means regulating flow to and from said chamber inlet and outlet respectively.

Claims

1. A pneumatic motor for reciprocating a member comprising: a chamber including a pressure responsive member as a wall thereof; means urging the pressure responsive member in a direction to contract the chamber; an inlet into said chamber; a valve seat and valve member controlling flow through said inlet, said inlet valve member having a pressure responsive surface exposed to upstream pressure; an outlet from said chamber; a valve seat and valve member controlling flow through said outlet, said outlet valve member having a pressure responsive surface exposed to pressure within said chamber; means including reSilient means between said pressure responsive member and said inlet and outlet valves for alternatively opening said inlet valve against the force of inlet pressure on movement of the pressure responsive member in a direction contracting said chamber and opening said outlet valve against the force of chamber pressure on movement of the pressure responsive member in a direction to expand said chamber; a regulator valve controlling pressure of gas supplied to said inlet, said regulator valve including a spring chamber having a spring therein urging the pressure responsive member of the regulator valve toward valve opening position; and a conduit connecting said chamber of the motor to said spring chamber.

4. Apparatus comprising: a fluid handling device having a reciprocating member; a pneumatic motor having a chamber including a pressure responsive member as one wall thereof; means connecting the reciprocating member to said pressure responsive member; an inlet into said chamber; inlet valve means controlling flow through said inlet; an outlet from said chamber; outlet valve means controlling flow through said outlet; means responsive to reciprocation of said reciprocating member for alternatively opening and closing said inlet and outlet valve means; a regulator valve controlling pressure of fluid to said inlet; valve means controlling flow of fluids to and from said inlet and outlet; and conduit means between said chamber and the regulator valve spring chamber whereby pressure in the motor chamber affects operation of the regulator valve.

6. A pneumatic motor for reciprocating a member comprising: a chamber including a pressure responsive member as a wall thereof; means urging the pressure responsive member in a direction to contract the chamber; an inlet into said chamber; a valve seat and valve member controlling flow through said inlet, said inlet valve member having a pressure responsive surface exposed to upstream pressure; an outlet from said chamber; a valve seat and valve member controlling flow through said outlet, said outlet valve member having a pressure responsive surface exposed to pressure within said chamber; shell means attached to said inlet and outlet valve members and alternatively seating and unseating said inlet and outlet valve members with movement of said shell means; a first relay having a lost motion connection with said shell means; a second relay reciprocal relative to said shell means and first relay; a lost motion connection means between said pressure responsive member and said second relay; resilient means between said first and second relays; and means regulating the pressure of gas supplied to said inlet.

8. A pneumatic motor for reciprocating a member comprising: a chamber including a pressure responsive member as a wall thereof; means urging the pressure responsive member in a direction to contract the chamber; an inlet into said chamber; a valve seat and valve member controlling flow thrOugh said inlet, said inlet valve member having a pressure responsive surface exposed to upstream pressure; an outlet from said chamber; a valve seat and valve member controlling flow through said outlet, said outlet valve member having a pressure responsive surface exposed to pressure within said chamber; shell means attached to said inlet and outlet valve members and alternatively seating and unseating said inlet and outlet valve members with movement of said shell means; double lost motion connection means between said shell means and said pressure responsive member; resilient means urging each of said lost motion connection means toward extended position; and means regulating the pressure of gas supplied to said inlet.

10. A pneumatic motor for reciprocating a member comprising; a chamber including a pressure responsive member as a wall thereof; means urging the pressure responsive member in a direction to contract the chamber; an inlet into said chamber; a valve seat and valve member controlling flow through said inlet, said inlet valve member having a pressure responsive surface exposed to upstream pressure; an outlet from said chamber; a valve seat and valve member controlling flow through said outlet, said outlet valve member having a pressure responsive surface exposed to pressure within said chamber; shell means attached to said inlet and outlet valve members and alternatively seating and unseating said inlet and outlet valve members with movement of said shell means; a lost motion connection means between said shell means and pressure responsive member; resilient means urging said lost motion connection means toward its extended position; and means regulating the pressure of gas supplied to said inlet.

11. The motor of claim 10 in combination with valve means regulating flow to and from said chamber inlet and outlet respectively.