US2667180A - Control valve device - Google Patents

Description

19514 A. J. BENT CONTROL VALVE DEVICE Original Filed July 22, 19'4"? m3 0m NQ 09 NM all H zllllilll bl\\\ I N V EN TOR. Arthur J Bani qwwd AT TORNE Y Patented Jan. 26, 1954 UNITED STATES arm OFFICE CONTROL VALVE DEVICE Arthur J. Bent, Penn Township, Allegheny County, Pa., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania August 26, 1952.

Divided and this application January 23, 1951, Serial No. 207,337

3 Claims.

This invention relates to control valve devices of the self-lapping type and more particularly to a control valve device for controlling operation of a free piston machine, the present application being a division of my copending application Serial No. 33,044, filed June 15, 1948, which in turn is a division of my copending application No. 762,771, filed July 22, 1947, and now issued as Patent 2,608,052.

In Patent 2,406,037, issued on August 20, 1946, to R. P. Ramsey there is disclosed a free piston machine which embodies two oppositely and coaxially arranged motor compressor units each embodying a piston assembly comprising a power piston, an air compressing piston and a direct bounce piston, the two assemblies being arranged with a common power or combustion chamber between the two power pistons into which fuel is adapted to be injected for combustion to drive the two assemblies apart. At the outer face of each air compressing piston is an air compressing chamber and said piston is operative by the respective power piston to compress air from said chamber. At the outer face of each direct bounce piston is a cushion space known as the direct bounce chamber adapted to be supplied with fluid under pressure which is compressed on the air compressing stroke of the piston assembly to provide energy for moving the assembly inward preceding another power, air compressing stroke. At the opposite or inner face of the air compressing piston is What is known as a reverse bounce chamber which is employed in connection with starting of the machine and in which the amount of air is adapted to be manually varied for regulating, in addition to the usual regulation resulting from variations in fuel supply, frequency of reciprocation of the machine.

The principal object of the invention is the provision of an improved operators control valve device particularly adapted for regulating the amount of fluid under pressure in the reverse bounce chamber or chambers of a free piston machine, such as above described.

Other objects and advantages will become apparent from the following more detailed description of the invention.

In the accompanying drawing; Fig. 1 is a sectional, diagrammatic view of a control valve device embodying the invention; and Fig. 2 is a sectional view, at an enlarged scale, of a portion of the structure shown in Fig. 1.

Description As shown in the drawing, the improved control valve device comprises a casing containing a flexible diaphragm 48 subject on one side to atmospheric pressure in a chamber 49 which is open to atmosphere through a passage 50. At the opposite side of diaphragm 48 is a control chamber 5| adapted to be connected through a passage 52 to the reverse bounce chambers of a free piston machine (not shown) through a pickoff valve device (not shown) which will provide in said chamber 5| from the fluctuating pressure in said reverse bounce chambers a substantially constant, proportional or mean of the pressure in said reverse bounce chambers.

A diaphragm follower 54 contained in chamber 5! and engaging one side of diaphragm 48 has a stud portion 55 extending from one side thereof centrally through said diaphragm and secured by screw-threaded engagement to a sleeve 56 disposed in chamber 49. The sleeve 56 is provided at one end with an annular collar 51 engaging and urging a follower 58 against the opposite side of diaphragm 43 for securely clamping the central portion of said diaphragm between said follower and the follower 54.

A sleeve 59 project from the opposite side of diaphragm follower 54 through a bore in a partition wall 60 separating chamber 5! from a chamber GI and thence through another partition wall 62 separating chamber 6| from a chamber 63. Chamber 63 is adapted to be connected through a passage 6 to the reverse bounce chamber of a free piston machine (not shown) whereby pressure in chamber 63 will fluctuate with the pressure in said reverse bounce chamber during operation of said machine. Sealing rings 56 provided in the partition walls 60 and 62 have sealing and sliding contact with the sleeve 59 for preventing leakage of fluid under pressure from chambers 5| and 63 to chamber 6! which latter chamber is open toatmosphere through a passage 5?. A delivery pressure, regulating spring 68 contained in chamber 49 acts on the diaphragm 48 for urging'it in the direction-of partition wall 60. c

A post 69 secured at one end to the diaphragm follower 54 extends centrally through the sleeve 59 to a point in chamber 63 beyond the end of said sleeve, while secured to the opposite end of said post in said chamber is the closed end of a cylinder 10 the opposite open end of which is disposed adjacent and in coaxial relation with the open end of sleeve 59. S-lidably'mounted in cylinder 10 is a fluid pressure release valve 7! arranged to cooperate with the end of sleeve 59, constituting a seat for said valve, to control communication between chamber 63 and the interior of sleeve 59 which is open through one or more ports I2 in said sleeve to the atmospheric chamber 6|. A spring I3 contained in a chamber 74 formed between valve II and the closed end of cylinder I9 acts on said valve urging it toward its seat. Chamber I4 is open through a small port I5 in the closed end of cylinder 19 to chamber 63. The valve "II has a stem '59 slidably mounted on the post 69.

The post 69 has a through axial bore and slidably mounted in this bore is a plunger Ti having an axial bore I8 closed at opposite ends of the plunger. Near one end the plunger Tl has one or more radial ports "I9 establishing a constantly open communication between bore 18 and one or more radial ports 89 provided in the post 89 and opening to chamber I4. Near the opposite end the plunger 11 has one or more ports 8I connecting said bore to a release pilot valve chamber 82, it being therefore noted that chamber 82 and the release valve chamber I4 are in constant communication. A pilot release valve 83 contained in chamber 82 is arranged to control communication between said chamber and the atmospheric chamber 49 by way of a plurality of ports 84 in a seat member 85, a chamber 86 and a plurality of ports 81 in an equalizing member 88. The pilot valve 83 has a stem 89 extending through a suitable guide bore in seat member 85 into chamber 89 wherein it engages one side of an apertured spring follower 99. One end of a precompressed spring 9I contained in chamber 85 engages the opposite side of follower 99, while the opposite end of said spring is supported on a nut 92 adjustably mounted in the equalizing member 98. This spring is provided for unseating the release pilot valve 83 and for concurrently shifting the plunger 'I'I axially in post 69. Movement of plunger 'I'i in the opposite direction is adapted to seat the pilot release valve 83.

The equalizing member 98 has one end connected to the sleeve 55 which is secured to the diaphragm 48 for movement therewith. A balancing piston 93 is formed on the opposite end of equalizing member 88 and carries a sealing ring 94 having sealing and sliding contact with the wall of a bore in the casing, said piston separating a pressure chamber 95 at one side from a non-pressure chamber 99 at the opposite side which latter chamber is open to the atmospheric chamber 49 as by way of a passage 91. Chamber 95 is in constant communication through a passage 98 and passage 94 with the chamber 93. The diameter of the balance piston 93 is the same as that of sleeve 59 in chamber 83, so as to provide surfaces of said piston and of the release valve II, when seated, of equal areas subject opposingly to pressures of fluid in chambers 95 and 93, 14, whereby oscillation or fluctuations in pressure in passage 64, and thereby in said chambers will not influence positioning of said parts and of the interconnecting parts above described.

The end of chamber 83 opposite that through which extends the sleeve 59 is closed by a casing part 99 having a through bore and mounted in said bore in coaxial relation to said sleeve is a bushing I99. This bushing has at the end adjacent chamber 63 an annular stop collar. I9I seating in a recess in the casing portion 99, while engaging the opposite and outer side of the easing part and having screw-threaded engagement with an extended part of said bushing is a securing nut I92 for holding the bushing in place. A

4 number of sealing rings I93 spaced from each other are carried. by the bushing I99 and have sealing contact with the wall of the bore in which said bushing is disposed to prevent leakage of fluid under pressure between chamber 63 and various passages to be hereinafter mentioned.

Slidably mounted in the bushing I99 is a plunger I94 having at one end a stem I of smaller diameter extending through a bore in an inwardly extending collar I99 provided on the bushing I99 adjacent its outer end. A sealing ring I97 carried by collar I96 engages stern I95 for preventing leakage of fluid under pressure along said stem from a balancing chamber I98 formed between the outer end of plunger I94 and the adjacent surface of collar I96. The plunger I94 has an axial bore closed at the end adjacent the stem I95, while the opposite end is open to chamber 63, and disposed in this bore against a shoulder I99a is a supply valve seat member I99. The member I99 is provided with a sealing ring II9 engaging the wall of the bore for preventing leakage of fluid under pressure from a supply pressure or supply valve chamber III formed at the inner end of member I99 within said bore past said member to chamber 63. The seat member I99 is supported in place in plunger I94 by a ring II2 disposed in a recess in said plunger and engaged by the outer end of said seat member. A main supply valve H3 contained in the supply valve chamber III is provided for seating engagement with the adjacent end of seat member I99 for controlling flow of fluid under pressure from said chamber to chamber 83 by way of an axial bore I I4 extending part way through said member and thence through a plurality of ports I I5 provided around a central integral section II9 of said member. The supply valve H3 is provided with an axial bore and surrounding said bore and extending into chamber III is a valve seat arranged to be engaged by a supply pilot valve II'I contained in said chamber. The pilot valve II! is engaged by'a follower H8 subject to pressure of a spring II9 for seating said pilot valve and in turn the supply valve II3. A pin I29 having a fluted portion I2I disposed within bore H4 in the seat member I99 has a coextensive fluted portion I22 of smaller diameter extending through the axial bore in the supply valve I I3 into engagement with the supply pilotvalve II'I, a shoulder I62 being formed at the junction of the larger and smaller fluted portions. This shoulder I52 is spaced from the supply valve II3 when the pilot valve I I1 is seated thereon but is adapted to engage and unseat said supply valve subsequent to unseating said pilot valve. The pin I29 has a bearing part I23 extending in the oppositedirection from the fluted portions thereof through and in sliding contact with the axial bore in the integral section III; of the seat member I99 into chamber 63 for engagement with the adjacent end of plunger 11;

The supply valve chamber I I I is adapted to be constantly supplied with fluid at a desired pressure through a passage I25 connected to a cavity I21 surrounding the bushing I99 and thence through one or more ports I28 in said bushing, an annular chamber I29 formed between said bushing and plunger I94 and encircling the latter, and one or more radial ports I29a in said plunger opening to chamber III.

The chamber 93 at one end of plunger I94 is open through a passage I30 to chamber I98 at the opposite endvfor constantly.equalizing-pressures of fluid therein to minimize the force required to move said plunger in the direction of chamber 63 when the latter chamber is supplied with fluid under pressure, as will be later described. Secured by a ring I3I to the plunger stem I05 adjacent the outer end thereof is a spring seat I32 and interposed between said seat and the bushing collar I06 is a bias spring I33 acting constantly to urge the plunger I04 outwardly of the casing part 99.

At one side of the plunger stem I05 the casing part 99 has an integrally formed projecting arm I34 in which there is secured by a pin I35 a shaft I36 extending parallel to the axis of said stem, and mounted to turn on this shaft in a plane at right angles to the axis of said shaft and stem is an operators control lever I31. The lever I3? is secured against movement axially of the shaft I38 by means not shown in the drawing.

The lever I3! is provided with a cam element 548 having a cam surface I50 engaging one side of a follower I5I the opposite side of which engages the plunger stem I05, said cam being adapted when the lever I31 is in the position in which it is shown in the drawing to permit spring i 53 to urge plunger I04 into contact with the bushing collar I05, while upon movement of said lever from this position in a direction away from the reader, said cam will displace said plunger in the direction of chamber 63 a distance proportional to the extent of such movement.

Operation With plunger I04 in contact with the bushing collar I05, spring II9 will be seating the supply pilot valve Ill and supply valve I I3, the regulating spring 58 will position follower 54 in contact with the casing partition 80, and spring SI acting on the release pilot valve 83 and holding stem I? in contact with stem I20, in turn in contact with said supply pilot valve II'I, will hold said release pilot valve unseated. With the release pilot valve 83 open, chamber I4 and thereby chamber 63, passage 64 and the balancing piston chamber 95 will be vented to atmosphere through port I5 in cylinder 10, port 80 in post 83, port in plunger 11, thence through the axial bore 18 and port 8I in plunger 11, chamber 82, past said release pilot valve, through port 84, chamber 86, port 81, regulating spring chamber 49 and passage 50. Since chamber 59 is open to chamber 63 via the reverse bounce chambers in the free piston machine (not shown) said chamber 5| will at this time also be vented permitting contact between the diaphragm follower 54 and partition wall 60 as above mentioned. With chambers 63 and I4 both vented spring I3 will be seating the release valve N.

If the lever I3! is now turned in a direction away from the reader, the cam I46 and follower I5! will be operated to displace, as a unit, the plunger H04, the seated supply valve II 3, the seated supply pilot valve Hi, the pin I20 and the plunger I? against the release pilot valve 83 and move said release pilot valve against spring eI until it becomes seated. When the release pilot valve 83 becomes seated as just described it will hold the plunger I1 and thereby the pin I20 against further movement whereupon continued movement of the plunger I 04 in the direction of these parts will cause said pin to first unseat the supply pilot valve Ill and then the supply valve I I3, whereupon fluid under pressure from the supply valve chamber I I I will flow past said supply valves to chamber '83 and thence through passage 64 to the reverse bounce chambers in the free piston machine (not shown). Fluid from chamber 63 will also flow by way of passages 54 and 98 to the balancing piston chamber 05 to act on the piston 93 to counterbalance the same pressure acting in chamber 63 on the cylinder I0.

When fluid under pressure is thus supplied to chamber 63 and the reverse bounce chambers of the free piston machine the pressure of such fluid will fluctuate with operation of said machine, but a substantially constant proportional or mean of such pressure will become effective through passage 52 in chamber 5I which will deflect the diaphragm 48 against the regulating spring 68 in accordance with the increase in such pressure, and relative to plunger I04 assuming that movement of lever I31 and of said plunger has been limited to some chosen degree. As the diaphragm 48 thus deflects under pressure of fluid becoming efiective in chamber 5|, the seated release pilot valve 83, plunger I'I, pin I20, supply valve H3 and supply pilot valve II! will, under the action of spring I I9, move therewith relative to plunger I04 until both of said supply valves become seated to terminate supply of fluid under pressure to chamber 63 and thereby the increase in pressure of fluid in chamber 5I, whereupon deflection of diaphragm 48 against spring 68 will cease, it being noted that the quantity of fluid under pressure obtained in chamber 63 and the pressure of fluid obtained in chamber 5| is limited according to the position of lever I31. I

If the lever I3! is moved further away from the operator the plunger I04 will be displaced further in the direction of diaphragm 38 and, as a result, fluid under pressure will again be supplied to chamber 63 until a proportional increase is obtained in chamber 5| whereupon deflection of diaphragm 48 will permit closing of the pilot supply valve II! and supply valve II3 to prevent further supply.

On the other hand, if lever I37 is pulled toward the operator the cam I48 will be so adjusted as to permit spring I33 to actuate the plunger I04 in the direction of said cam. The seated supply valve [I3 and seated supply pilot valve II! will move with the plunger I04 and thus permit spring 9| acting on the release pilot valve 83 to move said pilot valve and the plunger TI along with the pin I20 and plunger I04 relative to the post 69 connected to the diaphragm 48. This movement of the release pilot valve 83 will therefore be relative to and out of contact with the seat member 85whereupon fluid under pressure will be vented from chamber "Id within the cylinder I0 at a rate exceeding the rate of supply through the port 75. When the pressure of fluid in chamber '14 is thus sufficiently reduced the pressure of fluid in chamber 63 acting on the opposite side of the release valve lI will unseat said valve from the end of sleeve 58 against the opposing force of spring I3 whereupon fluid under pressure will be released from chamber 63 and thereby from the reverse bounce chambers in the free piston machine (not shown) to the interior of sleeve 59 and thence through port I2, chamber II and passage 61 to atmosphere.

As air is thus released from the reverse bounce chambers in the free piston machine the mean reverse bounce chamber pressure effective in diaphragm chamber 5| will correspondingly reduce which will permit spring 68 todeflect the diaphragm 48 in the direction of chamber Now assuming that movement of the operator's control handle I31 and thereby of the release pilot valve 83 has ceased, this deflection of diaphragm 48 and of the seat member 85 will be relative to the release pilot valve 83 and finally said seat member will contact said pilot valve in a position of the diaphragm 48 corresponding to that of the operators control lever 131. When the release pilot valve 83 is thus seated the flow of fluid under pressure from chamber 63 through port '15 into chamber 14 of the cylinder will increase the pressure in said chamber to a degree to permit spring to seat the release valve 1 l against the end of sleeve 59 for preventing further release of air from the reverse bounce chambers. The amount of air in the reverse bounce chambers will thus reduce to a degree corresponding to the new position of the operators control lever {31.

If the lever I31 is pulled still closer to-the reader the amount of fluid under pressure present in chamber 63 and the reverse bounce chambers of the free piston machine will reduce further until the substantial mean of the pressure in said chambers acting in chamber 5| is reduced sunlciently for the release pilot valve 8-3 to again seat for limiting such reduction in accordance with theposition of lever I31.

If the lever 131 is returned to the position in which it is shown in the drawing, a complete release of fluid under pressure from chambers 63 and 51 will occur since the diaphragm follower 54 will engage the casing partition 60 with the release pilot valve 83 still open.

It will now be seen that by suitable adjustment of lever I37 any desired amount of fluid may be provided in chamber 63- and thereby in the reverse bounce chambers of a free. piston machine wherein during operation of said machine the pressure of such fluid will vary between maximum and minimum values. during each stroke of the machine, the substantially constant mean of such varying pressures acting in chamber 5| to limit said amount of fluid in accordance with the position of lever I31. By moving the lever 13'! away from the reader the amount of fluid pressure in chamber 63 will be. increased, according to the extent of such movement, while movement of said lever toward the reader will correspondingly reduce the amount of fluid under pressure present in chamber 63.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A fluid pressure control valve device comprising a casing, a. fluid pressure. controlling assemblage in said casing comprising a movable abutment subject on one side to pressure of fluid in a pressure control chamber, a regulating spring opposing pressure of fluid in said chamher on said abutment, said assemblage further comprising a sleeve carried by said abutment and projecting into another chamber, a valve in said other chamber cooperative with the end of said sleeve to control a fluid. flow communication to said other chamber, a. piston of the same area as the end of said sleeve associated with said abutment at the opposite side thereof, said casing cooperating with said piston to form a balancing chamber at the outer face thereof, and means opening said balancing chamber to said other chamber.

2. A fluid pressure control valve device comprising a casing, a fluid pressure controlling assemblage in said casing comprising a movable abutment subject on one side to pressure of fluid in a pressure control chamber, a regulating spring opposing pressure of fluid in said chamber on said. abutment, a sleeve carried by said abutment and projectin into another chamber, a cylinder disposed in said other chamber and carried by said abutment, a valve slidably mounted in said cylinder and arranged to cooperate with the end ofsaid sleeve for controlling a fluid flow communication to said other chamber, a chamber in said cylinder at one side of said valve, a restricted port connecting the last named chamber to said other chamber, a valve carried by said movable abutment controlling a fluid pressure release communication from the last named chamber, and meansfor opening and closing said valve.

3. A fluid pressure control valve device comprising a casing, a fluid pressure controlling as semblage in said casing comprising a movable abutment subject on one side to pressure of fluid in a pressure control chamber, a regulating spring opposing pressure of fluid in said chamber on said abutment, a sleeve carried by said abutment and projecting into a second chamber, a hollow post-like element carried by said abutment and projecting centrally through said sleeve into said other chamber, a cylinder carried by said post in said other chamber and having one end opening in the direction of the open end of said sleeve, a valve slidably mounted on said post and in said cylinder for seating cooperation with the end of said sleeve, said valve cooperating with the opposite end of said cylinder which is closed to form another control chamber, a restricted port connecting said second chamber to said other control chamber, ahollow member slidably mounted in andv extending through said post, means opening said other control chamber to the interior of said hollow member, a. pilot valve chamber in said abutment means, means opening said pilot valve chamber to the interior of said hollow member, a pilot valve in said pilot valve chamber cooperating with said abutment means to control a fluid. release communication from said other control chamber, and means controlled by movement of said hollow member relative to said post to control opening. and closing of said pilot valve.

ARTHUR J. BENT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,366,853 Wainwright Jan. 25, 1921 1,6451-700 Hodge Oct. 18, 1927 2,389,020 Bent Nov; 13, 1945 $512,013 Down. June 20, 1950 2,546,677 Rockwell Mar; 27, 1951

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