US3152517A

US3152517A - Reciprocating piston engine

Info

Publication number: US3152517A
Application number: US258731A
Authority: US
Inventors: Brian K Woolfenden
Original assignee: Air Products and Chemicals Inc
Current assignee: Air Products and Chemicals Inc
Priority date: 1963-02-15
Filing date: 1963-02-15
Publication date: 1964-10-13
Anticipated expiration: 1981-10-13
Also published as: GB1046882A

Description

Oct. 13, 1964 B. K. WOOLFENDEN 3,152,517

. RECIPROCATING PISTON ENGINE 3 Sheets-Sheet 1 Filed Feb. 15, 1963 FIG?) INVENTOR BRIAN K. WOOLFENDEN ATTORNEYS Oct. 13, 1964 a. K. WOOLFENDEN 3,152,517

RECIPROCATING PISTON ENGINE Filed Feb. 15, 1965 s Sheets-Sheet 5 FIGS fr 4,, I FIGIO FIG."

INVENTOR BRIAN K. WOOLFENDEN BY United States Patent 3,152,517 RECIFRGCA'IING PISTON ENGINE Brian K. Wooitenden, Grafton, NFL, assignor to Air Froducts will Chemicais, Inc a corporation or Deiaware Filed Feb. 15, 1963, Ser. No. 25%,731 I4 Ciairns. (Cl. 91-247) The present invention relates to reciprocating piston engines, more particularly of the type in which a gaseous fluid is expanded with the performance of external work or is compressed by the performance of Work. The invention will be described and illustrated in one exemplary embodiment as an expansion engine; however, it is to be expressiy understood that except as indicated in certain of the more specific claims, the invention is equally well adapted for embodiment in a compressor.

It is an object of the present invention to provide a reciprocating piston engine that can be fully lubricated without contaminating with the lubricant the gas that is being expanded or compressed.

Another object of the present invention is the provision of a reciprocating piston engine in which novel and improved means for counterbalancing the inertia of the piston are provided.

Still another object of the present invention is the provision of a reciprocating piston engine having novel and improved valve-actuator arrangements.

Finally, it is an object of the present invention to provide a reciprocating piston engine that will be relatively simple and inexpensive to manufacture, easy to operate, maintain and repair, and rugged and durable in use.

Other objects and advantages of the present invention will become apparent from a consideration of the following description, taken in connection with the accompanying drawings, in which:

FIGURE 1 is a side elevation with parts broken away of the cylinder and piston portion of the engine of the present invention;

FIGURE 2 is a cross-sectional view taken on the line 2-2 of FIGURE 1;

FIGURE 3 is a top plan view of the structure of FIG- URE 1;

FIGURE 4 is a cross-sectional view taken on the line 44 of FIGURE 1;

FIGURE 5 is another cross-sectional View, taken on the line 55 of FIGURE 1;

FIGURE 6 is a side elevational view of the running gear of the present invention;

FIGURE 7 is a top plan view of the structure of FIG- URE 6 with a portion of the top cover plate removed;

FIGURE 8 is a cross-sectional view on the line 88 of FIGURE 6;

FIGURE 9 is a cross-sectional View taken on the line 9-9 of FIGURE 6;

FIGURE 10 is a cross-sectional view taken on the line litill of FIGURE 7;

FIGURE 11 is a View similar to FIGURE 10 but taken on the line IIII of FIGURE 7;

FIGURE 12 is a plan view of a lever element of the invention; and

FIGURE 13 is an elevational View of the lever element of FIGURE 12.

Referring now to the drawings in greater detail, the invention is shown embodied for example in an expansion engine of the reciprocating piston type, of the general type shown in US. Patents Nos. 2,607,322 and 2,678,028, comprising a supporting plate I to which is secured a cylindrical casing 3 that forms a portion of the outer casing of the expansion engine and that houses the cylinder and piston part of the engine. A cylinder 5 is disposed within casing 3 and is spaced from the inner side walls of ice casing 3. If desired, casing 3 may be evacuated or filled with insulation or both, to reduce heat transfer to or from the cylinder and piston. A piston 7 reciprocates in cylinder 5 axially thereof, and a breather port 9 assures that pressure or vacuum in the closed end of cylinder 5 will not interfere with movement of piston 7 therein.

Cylinder 5 is provided with an inlet port 11 and an outlet port I3 communicating between the interior of the cylinder and an inlet conduit 15 and an outlet conduit 17, respectively. Conduits I5 and I7 are disposed outside of cylinder 5 but inside casing 35 and extend lengthwise of easing 3 to what is the lower end thereof in FIGURES 1 and 2, where they are secured in fluid-tight relationship with casing 3 by means of seals 19. Connections 21 connect conduits I5 and 17 with sources of relatively high and low pressure working fluid, respectively, so that high pressure working fluid flows in through a connection 21 to and through inlet conduit 15 through inlet port II to the interior of cylinder 5 to power the expansion stroke of the piston, and back out through outlet port I3 and outlet conduit I7 and the associated connection 21 upon the return or exhaust stroke of piston 7.

An inlet valve 23 and an outlet valve 25 control the admission of compressed working fluid to and the exhaust of expanded working fluid from inlet port 11 and outlet port 13, respectively. Each of

valves

23 and 25 is mounted for reciprocation parallel to the axis of cylinder 5 on an inlet valve rod 27 and an outlet valve rod 2Q, respectively, that are greatly elongated and that extend most of the length of easing 3.

Rods

27 and 29 extend through and beyond plate I and terminate in ends remote from valves 2?: and 25 that are provided with enlargements 31 for coaction with the running gear to be described below. Coil compression springs 33

encircle valve rods

27 and 29 and act between

valves

23 and 25 and fixed abutments continuously to urge

valves

23 and 25 toward closed or seated relationship on the margins of inlet and outlet ports I]. and I3. Packing 35 surrounds

valve rods

27 and 29 in fluid sealing relationship substantially to prevent escape of the working fluid.

A piston rod 37 is secured at what is its lower end in FIGURES 1 and 2 Within piston 7 and extends axially of cylinder 5 and piston 7 through and beyond plate 1 and terminates in a clevls 39 by which it is secured to the running gear in a manner to be described below.

The running gear is positioned as best seen in FIGURE 6, above plate I in that figure and generally on the opposite side of plate I from the cylinder and piston assembly. Housing 41 is secured as by bolting to plate I and includes a removable top cover plate 43 and a removable side cover plate 45 which are preferably made fluid tight with the remainder of housing 41 by means of appropriate gaskets.

An important feature of the present invention is that the interior of running gear housing 41 is divided by a partition 47 into two

chambers

49 and 51 and are in fluid-sealed relationship to each other. Chamber 49 receives the upper ends of piston rod 37 and

valve rods

27 and 29; and of course it is impossible completely to seal chamber 49 from fluid communication with the working chamber defined by the cylinder and piston. Chamber 51, on the other hand, contains the running gear that needs lubrication and can be completely lubricated as by being maintained substantially full of liquid lubricant. However, because partition 47

seals chambers

49 and 51 from each other, the lubricant does not get back to chamber 49 and does not contaminate the working fluid in chamber49, with the result that the working fluid in chamber 49 cannot contaminate the working fluid in the working chamber of the expansion engine. It will of course be appreciated that it is particularly important to maintain the working fluid free from lubricant and other contaminants in very low temperature expansion operations such as the expansion of helium to a few degrees above its liquefaction temperature, for at those very low temperatures any hydrocarbonaceous lubricant contaminating the working fluid would be in solid phase and could seriously obstruct the operation of the engine.

Among the principal operative elements of the running gear within housing 41 are a first rockshaft 53 and

second rockshafts

55 and 57. These three rockshafts are all parallel to each other and their axes are all perpendicular to but spaced from the line of reciprocation of piston 7.

All three of these

rockshafts

53, 55 and 57 also extend through and are journaled for rotation in and relative to partition 47. As a result, they would offer an opportunity for contaminant to flow from chamber 51 to chamber 49 if the pathway for such contaminant were not sealed oif. To seal off this pathway, each of these three rockshafts is provided with a seal, and the seal for first rockshaft 53 will be described in detail with the understanding that essentially the same seal is used for

second rockshafts

55 and 57.

The seal for rockshaft 53 includes a sleeve 59 which is fixedly secured as by welding or brazing or the like in partition 47. A further sleeve 61 is mounted in a wall of housing 41 and provides a bearing for what is the lower end of rockshaft 53 as seen in FIGURE 8. A seal 63 extends between and prevents fluid flow between rockshaft 53 and partition 47. Seal '53 includes a flexible sleeve 65 of fluid-impervious material, for example synthetic rubber, that encompasses rockshaft 53 and is secured at one end to and entirely about rockshaft 53 and at its other end to and entirely about sleeve 59, which in this instance serves as an adaptor portion of partition 4-7 for purposes of securement of sleeve 65 to partition 4'7. Sleeve 65 is spaced radially outwardly from rockshaft 53, and the annular cylindrical space between sleeve 65 and rockshaft 53 is filled at least in part by a plurality of independent floating rings 67 that prevent collapse of sleeve 65 under pressure.

As was mentioned above, the seals of

second rockshafts

55 and 57 are essentially the same as those of first rockshaft 53; and hence, it will suffice merely to observe that rockshaft 55 is provided with a journal sleeve 69 and rockshaft 57 is provided with a journal sleeve 71 in which the respective second rockshafts are mounted for rotative movement, rockshaft 55 being provided with a flexible seal 73 similar to seal 63 and rockshaft 57 being provided with a flexible seal 75 which is also similar to seal 63. A low partition 77 extends part of the way from the bottom toward the top of housing 41 within chamber 51, as is seen best in FIGURES 7-10; and sleeves 69 and 71, in addition to being fixedly mounted in partition 47 as by welding or brazing or other fluid-tight connection, also extend through and are supported by partition 77.

First rockshaft 53 is provided with three outwardly extending

rocker arms

79, 81 and 83. Rocker arm 79 is on the end of rockshaft 53 within chamber 49 and is pivotally interconnected with clevis 39 of piston rod 37 of the expansion engine, so that upon reciprocation of piston 7 under the impetus of the expanding working fluid, the moving piston oscillates rocker arm 79 and causes first rockshaft 53 to have a rocking movement that drives the entire running gear.

As is seen in FIGURE 11, rocker arm 81 of first rockshaft 53 engages with a first-class lever 85 journaled for rotation on a shaft 57 that is carried by partitions 47 and 77 and that is fixed against rotation by means of a set screw 89 in partition 77, as is best seen in FIG- URES 9, and 11. lever 85 has a pair of arms that extend generally in opposite directions from the bearing shaft 87, one of these arms being provided with a groove 91 in which rocker arm 81 rides as best seen in FIGURES 9 and 11, and the other of the arms of lever 35 terminating in a clevis 93, best seen in FIGURES 9 and 11. A shaft 95 extends between and is mounted at its ends in the top and bottom plates of housing 41, as best seen in FIGURE 11, and is parallel to the line of movement of piston 7. A counterweight 9'7 is slidabiy mounted on shaft 95 for vertical reciprocatory movement as seen in FIGURE 11, and a coil compression spring 99 acts be tween top cover plate 43 and counterweight 97 continuously to urge counterweight 97 downwardly as seen in FEGURE ll. Thus, as piston 7 moves downwardly, rockshaft 53 is rocked clockwise as seen in FIGURE 11, so that rocker arm 31 moves downwardly or clockwise as seen in FIGURE 11, which causes lever 85 to turn counterclockwise so that clevis 9-3 raises counterweight 97 against the action of spring 99. The mass of counterweight 97 is so selected that it balances piston 7 and the parts that move in association with piston '7, so that as piston 7 goes down, counterweight 97 goes up, and vice versa. Piston 7 is thus dynamically balanced by a unique lever train that avoids the need for the crank and pitman assemblies disclosed by the prior art.

The remaining rocker arm 83 of first rockshaft 53 bears in rolling contact against antifriction roller 1G1 rotatably mounted on a crankpin 1% carried by and eccentric to the axis of a crankshaft 195 that is journaled for rotation in partition '77 in ball bearings 107 and in ball bearings 16? carried by a housing plate 111 removably secured to a side wall of running gear housing 41. Housing plate 111 also carries an annular seal 113 on the outer side of ball bearings 1&9 that seals against crankshaft to avoid the loss of substantial quantities of lubricant past crankshaft 105 where it leaves running gear housing 41. At its end within chamber 51, crankshaft 1&5 carries a counterweight 115 mounted on crankpin 1'93 and extending from crankpin 103 in a direction opposite to the direction in which crankpin 193 extends from crankshaft H15. Counterweight 115 is of a mass and is so positioned that it dynamically balances the eccentric mass of crankpin 193, so that crankshaft 135 is dynamically balanced about its axis. The other end 117 of crankshaft 105 extends outside running gear housing 4-1 and may be attached to a work-consuming mechanism such as a generator for recovering the work of isentropic expansion of the working fluid. If the engine is used as a compressor, however, then it is to end 117 of crankshaft 105 that the power is applied to reverse the work of the machine and to compress the working fluid. In other words, as an expansion engine, the piston drives rockshaft 53 which drives crankshaft 105; but as a compressor, crankshaft 105 drives rockshaft 53 which in turn drives piston 7.

Cam means are mounted for rotation on crankshaft 105; and as will appear later, it is these cam means that control the operation of the inlet and outlet valves of the working chamber of the engine. These cam means have a rotary cam face 119 that encompasses crankshaft 105 and is carried by a split sleeve 121 that releasably grips crankshaft 105. A further rotary cam face 123 is provided by the outer periphery of a collar 125 that encircles a split portion of sleeve 121. An internally screwthreaded nut 127 can be tightened against collar 125 to cause split sleeve 121 to grip crankshaft 105 to fix the cams on the crankshaft. Each of cam faces 119 and 123 r is provided with appropriate contours disposed various distances from the axis of rotation of crankshaft 105, thereby to control the onset and the duration and the termination of the opening and closing movements of the valve. Of course, both of these cam faces can he adjustably rotated relative to crankshaft selectively to predetermine these functions.

Cam face 119 contacts and rocks a rocker arm 129 that is in unitary assembly with rockshaft 57, on the end of rockshaft 57 that is within chamber 51, as best seen in FIGURES 9 and 10. At its other end, in chamber 49, rockshaft 57 carries a rocker arm 131 that engages under the enlargement 31 on the upper end of outlet valve rod 29. Thus, when cam face 119 rotates so that its outermost portion or highest contour contacts and rocks rocker arm 123 counterclockwise as seen in FIG- URE 10, the rocker arm 131 on the other end of rockshaft 57 will be raised and will raise outlet valve rod 29 as seen in FIGURE 2, which in turn opens outlet valve 25. When this raised contour of cam face 119 passes beyond rocker arm 129, rocker arm 129 moves clock- Wise as seen in FIGURE and resumes its former position, which causes the outlet valve rod to be released whereupon springs 33 close the outlet valve 25.

The other cam face 123 on collar 125 operates the inlet valve and contacts a lever 133 journaled for rotation on a shaft 135 parallel to all three rockshafts. Shaft 135 is mounted at its ends in partition 77 and the side wall of housing 41 that appears as the bottom wall in FIG- URE 8. As is also seen in FIGURE 8, housing plate 111 can be removed to give access to shaft 135 for replacement or repair. The configuration of lever 133 is best seen in the detail views of this member in FIG- URES l2 and 13. Lever 133 is there seen to have a pair of contact surfaces 137 and 139 that are spaced different distances from the axis of oscillation of lever 133.

In addition to being mounted for oscillation on shaft 135, lever 133 is axially slidable on shaft 135, and it is intended that one or the other of contact surfaces 137 and 139 be in contact selectively with cam face 123. Selection of the desired

contact surface

137 or 133 thus alters the time at which cam face 123 will act on lever 133 and correspondingly alters the timing of the operation of the inlet valve. To move lever 133 axially along shaft 135, a slot 141 is milled in the end of lever 133 opposite the

cam contacting surfaces

137 and 139, and an adjustor shaft 143 is mounted for rotation on and extends through a side wall of running gear housing 41, as is best seen in FIGURES 8 and 10. Shaft 143 is rotatable by manipulation of that portion thereof that is disposed outside of housing 41, and is provided with an eccentric crankpin 145 on its inner end that is disposed in slot 141. Upon rotation of shaft 143, therefore, lever 133 is slid axially of shaft 135 until the desired

contact surface

137 or 139 is in operative contact with cam face 123.

Lever 133 is in effect an intermediate rocker arm in the sense that it does not directly actuate anything but another rocker arm 147. This further rocker arm 147 is in unitary assembly with the end of rockshaft 55 that is disposed within chamber 51, so that rocking movement of lever 133 rocks rocker arm 147 in the same direction as lever 133. It should be noted, however, as is best seen in FIGURE 10, that the distance between the axis of shaft 135 and the point of contact of rocker arm 147 with lever 133 is substantially less than the distance between the axis of shaft 135 and the point of contact of

surface

137 or 139 with cam face 123. This means that the movements imparted to lever 133 by cam face 123 are transmitted to rocker arm 147 in greatly diminished magnitude, so that lever 133 in this sense functions as a second-class lever performing the function of motion reduction. This mechanical train from cam face 123 through lever 133 to rocker arm 147 thus provides a means for assuring that the movement of rocker arm 147 can be made more precise than if rocker arm 147 directly contacted cam face 123.

At its other end, that is, its end within chamber 49, rockshaft 55 carries a rocker arm 149 in unitary assembly therewith, rocker arm 149 at its end remote from rockshaft 55 engaging under the enlargement 131 at the upper end of inlet valve rod 27, so that upon notation of cam face 123 clockwise as seen in FIGURE 10, the raised profile of cam face 123 rocks lever 133 counterclockwise, which in turn rocks rocker arm 147 a lesser 5 angular distance counterclockwise, which in turn raises rocker arm 149 and lifts inlet valve 23 as seen in FIG- URE 2 to open the inlet to the working chamber of the expansion engine.

It will therefore be noted that the construction of this invention provides a unique running gear characterized in that it can be generously lubricated without danger of contaminating the working fluid with lubricant. This is achieved by eliminating the usual crank and pitman connections of the prior art and going instead to a plural rockshaft system which not only facilitates the provision of seals but also provides a simple and smoothly operating running gear. This running gear is further characteriZed by a unique counterweight mechanism. The rockshafts of the running gear also make it possible to operate the inlet and outlet valves of the engine in out-of-phase relationship to each other and to the operation of the piston, and adjustably to control the duration and timing of the operation of the valves relative to each other and relative to the piston so that any desired timing pattern for the operation of the engine can be quickly and easily achieved and accurately maintained.

In view of the foregoing disclosure, therefore, it will be obvious that all of the initially recited objects of the present invention have been achieved.

Although the present invention has been described and illustrated in connection with a preferred embodiment, it is to be understood that modifications and variations may be resorted to without departing from the spirit of the invention, as those skilled in this art will readily understand. For example, although the rockshafts are disclosed as having spaced parallel axes, they could instead have the form of concentric sleeves. Such modifications and variations are considered to be within the purview and scope of the present invention as defined by the appended claims.

What is claimed is:

1. An engine comprising a cylinder having inlet and outlet valves, a piston reciprocable in the cylinder, a first rockshaft, first means drivingly interconnecting the piston and the first rockshaft for conjoint reciprocation of the piston and rocking of the first rockshaft, a second rockshaft, second means interconnecting the first and second rockshaf-ts for conjoint out-of-phase rocking, third means interconnecting the second rockshaft and a said valve to open the valve upon rocking of the second rockshaft, and means sealing said first and third means from fluid communication with said second means.

2. An expansion engine comprising a cylinder having inlet and outlet valves, a piston reciprocable in the cylinder, a first rockshaft, first means interconnecting the piston and the first rockshaft to rock the first rockshaft upon reciprocation of the piston, a second rockshaft, second means interconnecting the first and second rockshafts to rock the second rockshaft out-of-phase with the first rockshaft upon rocking of the first rockshaft, third means interconnecting the second rockshaft and a said valve to open the valve upon rocking of the second rockshaft, and means sealing said first and third means from fluid communication with said second means.

3. An engine comprising a cylinder having inlet and outlet valves, a piston reciprocable in the cylinder, a first rockshaft, first means drivingly interconnecting the piston and the first rockshaft for conjoint reciprocation of the piston and rocking of the first rockshaft, a second rockshaft, second means interconnecting the first and second rockshafts for conjoint out-of-phase rocking, third means interconnecting the second rockshaft and a said valve to open the valve upon rocking of the second rockshaft, a housing having a pair of chambers and a partition sealing the chambers from fluid communication with each other, said first and third means being disposed in one chamber and said second means being disposed in the other chamber, the first and second rockshafts extending through the partition, and fluid sealing means sealing between the first it and second rockshafts and the partition to prevent the passage of fluid past the rockshafts between the chambers.

4. An engine as claimed in claim 3, said fiuid sealing means comprising a flexible sleeve of fluid-impervious material surrounding a rockshaft, the sleeve at one of its ends being sealed to and entirely about its associated rockshaft and at its other end being sealed in unitary assembly with the partition entirely about its associated rockshaft.

5. An expansion engine comprising a cylinder having inlet and outlet valves, a piston reciprocaole in the cylinder, a first rockshaft, first means interconnecting the piston and the first rockshaft to rock the first rockshaft upon reciprocation of the piston, a second rockshaft, second means interconnecting the first and second rockshafts to rock the second rockshaft out-of-phase with the first rockshafit upon rocking of the first rockshaft, third means interconnecting the second rockshaft and a said valve to open the valve upon rocking of the second rockshaft, a housing having a pair of chambers and a partition sealing the chambers from fluid communication with each other, said first and third means being disposed in one chamber and said second means being disposed in the other chamber, the first and second rockshafts extending through the partition, and fluid sealing means sealing between the first and second rockshafts and the partition to prevent the passage of fluid past the rockshaft between the chambers.

6. An expansion engine as claimed in claim 5, said fluid sealing means comprising a flexible sleeve of fluidimpervious material surrounding a rockshaft, the sleeve at one of its ends being sealed to and entirely about its associated rockshaft and at its other end being sealed in unitary assembly with the partition entirely about its associated rockshaft.

7. An engine comprising a cylinder having inlet and outlet valves, a piston reciprocable in the cylinder, a first rockshaft, means drivingly interconnecting the piston and the first rockshaft for conjoint reciprocation of the piston and rocking of the first rockshaft, a crankshaft parallel to the first rockshaft, means drivingly intercon-' meeting the first rockshaft and the crankshaft for conjoint rocking of the rockshaft and rotation of the crankshaft, cam means rotatable with the crankshaft, a second rockshaft, means interconnecting the cam means and the second rockshaft to rock the second rockshar't upon rotation of the cam means, and means interconnecting the second rockshaft and a said valve to open the valve upon rocking of the second rockshaft.

8. An engine as claimed in claim 7, said means interconnecting the first rockshaft and the crankshaft comprising an arm on the rockshaft coacting with a crankpin on the crankshaft.

9. An expansion engine comprising a cylinder having inlet and outlet valves, a piston reciprocable in the cylinder, a first rockshaft, means interconnecting the piston and the first rockshaft to rock the first rockshaft upon reciprocation of the piston, a crankshaft parallel to the first rockshaft, means interconnecting the first rockshaft and the crankshaft to rotate the crankshaft upon rocking of the first rockshaft, cam means rotatable with the crankshaft, a second reckshaft, means interconnecting the cam means and t e second rockshaft to rock the second rockshaft upon rotation of the cam means, and means interconnecting the second rockshaft and a said valve to open the valve upon rocking of the second rockshaft.

10. An expansion engine as claimed in claim 9, said means interconnecting said first rockshaft and the crankshaft comprising an arm on the rockshaft acting against a crankpin on the crankshaft.

11. An engine comprising a cylinder, a piston reciprocable in the cylinder, a rockshaft, means drivingly interconnecting the piston and the rockshaft for conjoint reciprocation of the piston and rocking of the rockshaft, a counterweight reciprocable parallel to the path of reciprocation of the piston, and means interconnecting the rockshaft and the counterweight to reciprocate the counterweight in opposite phase to the piston upon rocking of the rockshaft.

12. An engine as claimed in claim ll, the last-named means comprising a first-class lever having a pair of arms one of which is driven by the rockshaft and the other of which drives the counterweight.

13. An expansion engine comprising a cylinder, a piston reciprocable in the cylinder, a rockshaft, means interconnecting the piston and the rockshaft to rock the rockshaft upon reciprocation of the piston, a counterweight reciprocable parallel to the path of reciprocation of the piston, and means interconnecting the rockshaft and the counterweight to reciprocate the counterweight in opposite phase to the piston upon rocking of the rockshaft.

14. An expansion engine as claimed in claim 13, the last-named means comprising a first-class lever having a pair of arms one of which is driven by the rockshaft and the other of which drives the counterweight.

References Cited in the file of this patent UNITED STATES PATENTS 2,051,534 Skwierawski Aug. 18, 1936 2,235,204 Dadey Mar. 18, 1941 2,265,306 Orshansky Dec. 9, 1941 2,513,982 William July 4, 1950 3,063,725 Frey Nov. 13, 1962

Claims

1. AN ENGINE COMPRISING A CYLINDER HAVING INLET AND OUTLET VALVES, A PISTON RECIPROCABLE IN THE CYLINDER, A FIRST ROCKSHAFT, FIRST MEANS DRIVINGLY INTERCONNECTING THE PISTON AND THE FIRST ROCKSHAFT FOR CONJOINT RECIPROCATION OF THE PISTON AND ROCKING OF THE FIRST ROCKSHAFT, A SECOND ROCKSHAFT, SECOND MEANS INTERCONNECTING THE FIRST AND SECOND ROCKSHAFTS FOR CONJOINT OUT-OF-PHASE ROCKING, THIRD MEANS INTERCONNECTING THE SECOND ROCKSHAFT AND A SAID VALVE TO OPEN THE VALVE UPON ROCKING OF THE SECOND ROCKSHAFT, AND MEANS SEALING SAID FIRST AND THIRD MEANS FROM FLUID COMMUNICATION WITH SAID SECOND MEANS.