US2629363A

US2629363A - Reciprocatory engine

Info

Publication number: US2629363A
Application number: US134440A
Authority: US
Inventors: Gordon F Mcclay
Original assignee: Ingersoll Rand Co
Current assignee: Ingersoll Rand Co
Priority date: 1949-12-22
Filing date: 1949-12-22
Publication date: 1953-02-24
Anticipated expiration: 1970-02-24

Description

Feb. 24, 1953 G. F. MCCLAY 2,629,363

RECIPROCATORY ENGINE} Filed Dec. 22, 1949 INVENT-OR GORDON F. uccuw BY HIS ATTORNEY- Patented Feb. 24, 1953 RECIPROCATORY ENGINE Gordon F. McClay, Lennoxville, Quebec, Canada, assignor to Ingcrsoll-Rand Company, New York, N. Y., a corporation of New Jersey Application December 22, 1949, Serial No. 134,440

2 Claims.

This invention relates to engines, and more articularly to a pressure fluid actuated engine of the reciprocatory piston type.

The engine, constructed in accordance with the practice of the invention, is intended more particularly for use with an apparatus, or device, that is required to operate normally at a definitely rated speed and which speed may occasionally require variation. An example of such a device is that of a spray pipe serving to dislodge matter clinging to the screens used in the production of paper pulp.

In arrangements of this type, a pipe equipped with spray nozzles is caused to oscillate across the surface of the screen and the jets of water issuing from the nozzles are directed toward the screen to loosen and wash away the clogging matter. Owing to the importance of preventing the undue dilution of the paper pulp at some of the stages of its manufacture, it is essential that the movements of the spray pipe be so regulated as to effect a miximum flushing action with a minimum amount of spray, and it is, therefore, desirable that the stroke of the engine be variable in order that concentrations of blockin material may be quickly removed and that when the screen has been cleansed the speed of the engine may again be quickly and conveniently adjusted for normal operation.

It is accordingly an object of the invention to enable the speed of the engine to be conveniently and quickly varied in accordance with immediate requirements.

Other objects will be in part obvious and in part pointed out hereinafter.

In the drawings accompanying this specification and in which similar reference numerals refer to similar parts,

Figures 1 and 2 are longitudinal views, partly broken away, showing the movable parts of the engine in opposite hand limiting positions.

Referring more particularly to the drawings, the engine designated 20, in its entirety, comprises a cylinder 2| which is recessed to form a piston chamber 22 consisting of a large bore 23 and a reduced bore 24 that opens at one end into the large bore 23. At the opposite ends of the cylinder 2| are

external flanges

25 and 26 that respectively abut a head 21 and a support 28 and are secured to these parts by bolts 29.

A closure is provided for the outer end of the 2 to be actuated. The head 30 is recessed to receive a packing member 35 that encircles the rod 33 to prevent leakage of fluid from the piston chamber and said packing member is retained in position by a plate 36 overlying the outer end of the head 30 and held in assembled position by the bolts 3 I.

The rod 33 is separable from the piston 34 and has, to this end, a stem 31 threaded into the small portion or stem 38 of the piston lying within the bore 24. At the juncture of the stem 3'! and the body of the rod 33 is a shoulder 39 that bears against the portion, or head, 40 of the piston lying within the large bore 23 for pressing said head against the end of the portion 38.

The outer end of the head 40 constitutes a pressure surface 4| that is intermittently subjected to pressure fluid for actuating the piston in the direction of the head 21 and the free end of the stem 38 of the piston serves as a pressure surface 42 that is constantly subjected to pressure fluid conveyed thereto by a passage 43 leadin from an end portion 44 of a valve chamber 45 which is in constant communication, at said end portion, with a source of pressure fluid supply (not shown) through a conduit 45.

The valve chamber 45 extends transversely of the head 21. Its intermediate portion 41 is of reduced diameter and opens at one end into the end portion 44 and at its opposite end into a similar end portion 48. The ends of the portion 41 of the valve chamber contain

bushings

49 and 50 having beveled seats 5! and 52, respectively, for ball valves 53 and 54, and between the valves 53 and 54 is a spacer in the form of a rod 55 which is movable endwise in the

bushings

49 and 50 and of a length to prevent the valves from engaging their seats simultaneously.

The ball valve 53 is normally held on the seating surface 5! by the pressure fluid in the end portion 44 acting against an actuating surface 56 of said valve. Such pressure is augmented by a spring 51 that seats at one end against the valve 53 and at its other end against a closure 58 for the adjacent end of the valve chamber.

The force serving to lift the valve 53 off of its seat and press the valve 54 against the seating surface 52 is imparted thereto by a plunger 59 slidable in the portion 48 of the valve chamber and seating at one end against the valve 54. The opposite end of the plunger 59 rests upon a diaphragm 60 which is clamped, at its marginal portion, to the head 21 by a cover 6! and bolts 62, and in the cover is a chamber 53 into which pressure fluid is intermittently conveyed by a passage 64 in the head 2! and the cylinder 2|.

The passage 64 opens into the small bore 24 at a point near its juncture with the large bore 23 so that the piston will uncover it immediately prior to the end of its stroke. The passage 64 also conveys exhaust fluid from the chamber 63 and the small portion 38 of the piston is accordingly provided with an annular groove 65 adjacent the head 40 to register with the passage 64 in the opposite hand limiting position of the piston for conveying such fluid to a vent 66 at the inner end of the large bore 23.

In the form of the invention shown, the combined lengths of the

bushings

49 and 58 is less than the length of the intermediate portion 41 of the valve chamber so that a space 5'! exists therebetween and leading from said space is a passage 68 that extends through the head 21 and the cylinder 2| and opens into the outermost end of the large bore 23. The passage 63 serves both as a supply passage and an exhaust passage and .is provided with means for varying the rate of admission. to and the discharge of fluid from the bore 23. To this end a needle valve 55 is threaded into the cylinder to extend with its valve portion l into the passage 58 at the juncture of the latter with the bore 23. The fluid exhausted from the bore 23 returns to the space and passes through the bushing 53 into the end 58 of the valve chamber whence it passes to the atmosphere through an exhaust port H.

In the operation of the device, and assuming the movable parts of the engine to be in the positions shown in Figure 1, the pressure fluid entering the small bore 2& of the piston chamber will act against the pressure surface 42 to drive the piston in a right hand direction, as Figure l is viewed in the drawings. The chamber 63 Wfll then be open to the atmosphere through the passage 64, the annular groove 55 and the vent 69 so that the spring 5i and the pressure of the fluid against the actuating surface 56 will hold the valve 53 against the seating surface 5i to prevent the flow of pressure fluid into the space 61. In the closed position of the valve 53 the rod 55 will hold the valve 5 unseated to afford communication between the space 6? and the port l l Thus, as the piston moves rightwardly the air in advance of the head 20 will be expelled from the bore 23 through the passage 68 into the space El, thence through the bushing 50, the end portion 48 and the port H to the atmosphere.

As the piston approaches the end of its stroke, in the direction described, the free end of the small portion 33 uncovers the passage G4. Pressure fluid will then flow from the small bore 24 through said passage into the chamber 63 and, acting against the plunger 59 through the diaphragm Gil, will move the valve 54 against the seating surface 52 to cut-off communication between the passage 88 and the port l i. This movement of the valve 5Q, transmitted through the rod 55, will lift the valve 53 oil of its seat. Pressure fluid will then flow from the end '34 of the valve chamber through the bushing 49, the space 61 and the passage 68 into the outer end of the large bore 23 and drive the piston leftwardly, thereby completing the cycle of operation. During this movemnt of the piston pressure fluid will be expelled from the bore 24 through the constant supply passage 43 and the pressure fluid in the chamber 63 will be retained therein until the annular groove 65 registers With the passage 64. The fluid in the chamber 63 will then escape through the passage 66, the annular groove 65 and the vent 66 to the atmosphere to permit the return of the valve to its seat and the unseating of the valve 54 preparatory to a new cycle of operation.

Whenever, during the operation of the engine, it is desired to accelerate or decelerate the movement of the piston 34, the needle valve 69 may 4 be adjusted to either increase or decrease the flow area around the valve portion H! of the needle valve 69.

I claim:

1. A reciprocatory engine, comprising a casing having a differential bore, a reciprocatory piston in the bore having portions corresponding to the diameters of the bore, a passage in the casing to constantly admit pressure fluid into the small end of the bore, a second passage in the casing for conveying pressure fluid to and exhaust fluid from the opposite end of the bore, a valve chamber in the casing having an atmospheric vent, valve means in the valve chamber for controlling the flow of fluid to and from said second passage, a kicker passage in the casing controlled by the piston for valving pressure fluid to the valve means for throwing the valve means to a position for admitting pressure fluid into said second passage, an actuating surface on the valve means subjected constantly to pressure fluid tending to move the valve to a position for cuttingoif the admission of pressure fluid to said second passage and to establish communication between said second passage and the atmospheric vent, a spring acting against the valve means to augment the pressure of the fluid acting against the actuating surface, and means for selectively controlling the rate of flow of fluid through said second passage.

2. A reciprocatory engine, comprising a casing having a differential bore and an exhaust port for the bore, a reciprocatory piston in the bore having portions corresponding to the diameters of the bore, a passage in the casing to constantly admit pressure fluid into the small portion of the bore, a valve chamber in the casing having a vent, a second passage in the casing for conveying pressure fluid from the valve chamber to the large portion of the bore and to convey exhaust fluid from said large portion to the valve chamber, reciprocatory valve means in the valve chamber, fluid actuated means for throwing the valve to a position for admitting pressure fluid into said second passage, 2. kicker passage in the easing for conveying pressure fluid from the small portion of the bore to the fluid actuated means and being controlled by the piston, a groove in the piston for communicating the kicker passage with the exhaust port to permit the exhaust of the fluid acting against the pressure surface, an actuating surface on the valve means subjected constantly to pressure fluid tending to move the valve means to a position for cutting-01f the admission of pressure fluid to said second passage and to establish communication between said second passage and the vent, a spring to augment the pressure of the fluid against the actuating surface, and means for selectively controlling the rate of flow of fluid through said second passage.

GORDON F. MCCLAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number