US2922402A - Oscillating vapor engine - Google Patents

Description

Jan. 26, 1960 H. w. BALLARD 2,922,402

OSCILLATING VAPORENGINE Filed Jan. 29, 1958 M 3 Sheets-Sheet 1 //VVENTOR Jan. 26, 1960 H. w. BALLARD OSCILLATING VAPOR ENGINE 3 Sheets-Sheet 2 Filed Jan. 29, 1958 IIV VN TOR Jan. 26, 1960 H. w. BALLARD OSCILLATING VAPOR ENGINE 3 Sheets-Sheet 3 fqd Filed Jan. 29, 1958 lA/VENTOK United States Patent OSCILLATIN G VAPOR ENGINE Hyde W. Ballard, West Chester, Pa., assignor to Yapor Power Corporation, Columbus, Ohio, a corporation of Ohio Application January 29, 1958, Serial No. 712,027

3 Claims. (Cl. 121-65) This invention relates to vapor engines and more par ticularly to an improved oscillating steam engine of the type disclosed and claimed in the patents to E. B. Neil, 2,688,954 and 2,695,596.

In the development of small high pressure steam engines developing 5 to 30 horsepower, it has been found desirable to eliminate as many moving parts as possible and to control the valve action by oscillation of the cylinder. One manner of accomplishing this result has been tried in accordance with the design of the above-men tioned Neil patents. Difficulty with regard to the sealing of the valves when operating under high pressures has been encountered, and the present invention has for its primary object the provision of valve mechanism having an effective seal under pressures on the order of 1,000- 1,500 p.s.i.

The primary object of the invention, therefore, is to provide valve mechanism for an oscillating cylinder vapor engine having maximum sealing capacity for the valve seats.

A further object of the invention is to provide in an oscillating cylinder vapor engine an arcuate valve seat formed on a radius with the center of cylinder oscillation.

A further object of the invention is to provide a crankcase for an oscillating vapor engine in which the cylinder mounting comprises a cylindrical surface provided with valve ports.

A further object of the invention is to provide a pair of legs on the cylinder of an oscillating vapor engine which serve as valve ports and trunnions for the cylinder.

' A still further object of the invention is to provide in an oscillating cylinder vapor engine a spring loaded pressure pad for maintaining the valve seat surfaces in sealed relation.

Further objects will be apparent from the specification and drawings in which:

Fig. 1 is a longitudinal vertical section of a three cylinder vapor engine constructed in accordance with the present invention, 7

Fig. 2 is a transverse vertical section as seen at 2-2 of Fig. 1,

Fig. 3 is a transverse vertical section as seen at 3-3 of Fig. 1,

Figs. 47 are schematic sectional views showing the valve action during oscillation of one of the cylinders,

Fig. 8 is a side view of a single cylinder,

Fig. 9 is a front view of the cylinder of Fig. 8,

Fig. 10 is a top view of the cylinder of Figs. 8 and 9 and Fig. 11 is a transverse section of the piston as seen at 1111 of Fig. 2.

The invention comprises essentially the provision of a 2,922,402 Patented Jan. 26,1960

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ly extending valve port does not provide suflicient port area and angular travel to permit accurate opening and closing of the valve without undesired leakage. By locating the valve seat at the maximum distance from the center of oscillation, the valve port can be designed to open and close instantaneously. In addition, it is desir able to apply meansfor spring loading the valve seats, thereby insuring a tight seal at all times. Adequate bearing support for the piston may be provided by extending the pads and valve seats, both arcuately and axially, with the present design.

Referring now more particularly to the drawings, a three cylinder vapor engine is shown in Fig. 1 having a crankcase 15 in which the crankshaft 16 is journaled on bearings 17, 18 and 19, The crankcase 15 is so designed that the cylinders may be positioned either in a vertical or horizontal plane and, for this purpose, an oil sump is providedat 20 forvertical operation and at 2011 for horizontaloperation. In the latter case, thrust bearing 21 carries the axial load. The crankshaft 16 is provided with three crank throws 22, 23, 24 and 25 to which the crank ends or connecting rods 26, 27 and 28 of the pistons are. journaled respectively. Suitable roller or plain bearings 29 are employed for each crank throw. A piston 30 in each cylinder is formed integrally with connecting rods 26-28 and travels in the cylinders 31, 32 and 33, as is shown clearly in Figs. 47. The present engine has been designed with the crank throws 2225 set at so that the engine will be self-starting. It'will be understood that in thev event only one cylinder is desired, the operation will be the same but independent starting means will be required since the cylinder may stop with the vapor inlet in a closed position. The three cylinder engine. shown in Figs. l3 is provided with a vapor inlet manifold 35 and an exhaust manifold 36. Other accessories for the. engine, such as pumps, reverse control, condenser and vapor generator, have been omitted since they form no. part of the present invention.

The action of any one of the three cylinders 31-33 will be, described in detail and it will be understood that all cylinders are identical in construction and operation. Each piston 30. is provided with a longitudinally extend,- ing intake passage 4t) which terminates at one end at the top. of. the piston and at the other end near the bottom of the piston in a rightangle port'or passage 41. The piston is reinforced with suitable internal struts 42 and 43 (Fig. 11) and it is also desirably provided with piston rings 44, 45, some of which are positioned below the port or passage 41. Each cylinder has an exhaust port 46 at its top which is in the form of an elongated slot shown clearly in Fig. 10. The cylinder exhaust valve seat 47 is formed on a radius from the center of oscillation of the cylinder, 31-33 and fits in close sealing relation on the mating exhaust valve seat 48 formed in the cylindrical barrel of crankcase 15. Crankcase valve seat 48 can, if desired, extend substantially around the inside periphery of the crankcase, but for ease of manufacture, it has been found adequate to design the actual contact area of the valve seats 47 and 48 for adequate sealing and bearing areas.

Each cylinder 31-33 is integrally formed with a leg 50 having an arcuate convex intake valve seat 51 formed on a radius from the center of cylinder oscillation. The leg 50 is journaled on crankcase intake seat 52 formed on the inside periphery of the crankcase 15 and provided with an intake port 53. As in the case of valve seats 47 and 48, the seats 51 and 52 provide bearing support for the nection with Figs. 4-7.

A second leg 55 is formed integrally with each cylinder but in this case, leg 55 does not serve as a vapor passage. It, does; however, provide a third bearing surface for the cylinder, and a'pressure pad 56 (Figs. 2 and 3) is provided to maintain a predetermined, but adjustable, constant pressure on both the intake and exhaust valve seats. Pad 56 is desirably spring loaded by means of an adjusting screw 57 and a lock nut 58. The open areas between the individual cylinders which can be clearly seen in Fig. 1 permit oil to be splashed from the sump 20 or 20a as the case may be, onto the bearing surfaces of the cylinder legs and valve seats. The relief provided at 60 and 61 assists in the adequate lubrication of these sur faces; This is another important reason for locating the valve seats internally of the crankcase, rather than on the outside of the stationary engine structure as has been done in previous practice. i

The present engine is a modified uniflow type in'which steam is admitted at one end of the cylinder and exhausted near or at the opposite end so that there is little or no reverse flow of the steam. It must be pointed out, however, that the present invention follows the modification of the uniflow engine shown in the Neil patents in that the steam is actually admitted and exhausted atthe same end of the cylinder. The reason for this apparent in 3 and which will be described more fully in conhaust valves and it will be noted that intake valves are double sealed by both the piston and the cylinder leg 50 during the power stroke as shown in Fig. 6. The cylinder leg 50 is preferably extended circumferentially to provide a foot 67 which maintains the sealing of ports 53 and 54, even when the cylinder is oscillated to its maximum position on exhaust stroke as shown in Fig. 7.

. Continued tight scaling is provided by suitable spring loading of the pressure pad 56 so that there is no possibility for steam leaks to occur.

A steam engine constructed in accordance with the present invention is extremely inexpensive, eflicient and capable of developing high power with low weight. Moving parts have been reduced to an absolute minimum and no separate valve action or linkage is required.

Having thus described my invention, I claim:

1. An oscillating cylinder assembly for a vapor engine having an exhaust vapor passage at one end thereof, a bearingsurface surrounding said exhaust passage, an intake passage substantially at the mid-point of the cylinder, a bearing surface surrounding said intake vapor passage, a crankcase having a cylindrical bore in which said cylinder is journaled, bearing surfaces in the bore of the crankcontradiction resides inthe fact that no steam comes in contact with the cylinder walls until it has travelled through passages 40 and 41 in the piston. It therefore operates on the top of the piston to provide expansive force only after the admission port near the bottom of the cylinder has been closed by cylinder oscillation.

Referring now to Figs. 4-7, the piston is shown at top dead center in Figure 4 in which position steam is about to enter the cylinder through port 53, passage 54 and piston passages 40, 41. Exhaust valve port46 is closed in this position so that steam pressure is exerted against the cylinder head 65 forcing the piston 30 downwardly in the cylinder head 65 forcing the piston 30 downwardly in the cylinder. Just after passing bottom dead center (Fig. 6) the cylinder swings to align exhaust port 46 with exhaust passage 66 in the crankcase. The exhaust porting remains open during the upward stroke shown in Fig. 7 until the pressure in the cylinder has been reduced substantially to zero whereupon the cycle repeats. Oscillation of the cylinder in the crankcase provides the proper timing for both the intake and excase in sealing contact with the bearing surfaces of the cylinder, and means for spring loading the bearing surfaces on the cylinder against the bearing surfaces on the crankcase. l

2. Apparatus in accordance with claim 1 having an adjustable pressure pad in the crankcase in contact with the third bearing surface.

3. An oscillating cylinder assembly for a vapor engine having an exhaust vapor passage at one end thereof, a bearing surface surrounding said exhaust passage, an intake passage substantially at the mid-point of the cylinder, a bearing surface surrounding said intake vapor passage, a crankcase having a cylindrical bore in which said cylinder is journaled, bearing surfaces in the bore of the crankcase in sealing contact with the bearing surfaces of the cylinder and an adjustable pressure pad in the crankcase in contact with the third bearing surface,

References Cited in the file of this patent UNITED STATES PATENTS 271,741 Roth Feb. 6, 1883 323,298 Cunningham July 28, 1885 357,248 Todd Feb. 8, 1887 394,675

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