US2588478A - Engine - Google Patents

Description

Patented Mar. 11, 1952 ENGINE William. L. Brown, 3rd,v and William L. Brown, 4th, Philadelphia, Pa'.

Application November 27, 1946, Serial No; 712,524

4 Claims.

This invention relates. to engines,. and more particularly to engines which. may be built-in small sizes to serve as the power plants of model airplanes and the like.

It is the principalobjeot of the present invention to provide an engine capable of being operated by gas under pressure, stored in liquefied or compressedform, and in which adjustment of the speed of operation may be effected as desired.

It is a further. object of the present invention to provide an engine capable of operating on gas-under pressure, such as carbon dioxide, stored in liquefied or compressed form.

It is a further object of the present invention to provide, in an engine of the character aforesaid,an improved admission valve and actuation thereof.

It is a further object of the present invention to provide, in an engine of the character aforesaid, adequate provisions for lubrication.

Other objects and advantageous features of the invention will be apparent from the specification and claims. I

The nature and characteristic features of the invention will be more readily understood from the following description, taken in connection with the accompanying drawings forming. part hereof, in which:

Figure l is a view partly inelevation'andpartly in vertical section showing a preferred embodiment of an engine in accordance with the preslent invention;

Fig. 2 is a vertical sectional view taken approximately on the line 2-2 of Fig. 1 and Fig. 3 is a horizontal sectional view takenapproximately on the line 33 of Fig. 1-

It should, of course, be understoodfithat the description and drawings hereinare illustrative merely, and. that various modifications and changes may be made in the structure disclosed without departing from the spirit of the invention.

Referring more particularly to the drawings, the engine, inaccordance with the present inv'ention, preferably includes a crank case in preferably formed as a one piece die casting having one or more outstanding lugs ll through which bolts l2 are adapted to extend for mounting the engine in position in the fuselageof a model airplane, or in any other desired location.

opposite sideof the crankcase Ill preferably has.

shaft I5: is mounted for rotation. Thei'outer end of the crank shaft I5, beyondithe bearing tli, may be of reduced diameter, as...at. l-6,.ior the -reception of clamping disc's: H and l8, and the outer end: may also be threaded, asat l9; for the'zreiception of a nut-:20 for the: purposeof securing a propeller (-not shown) or other-driven m'em' her on the outer end of thecrank: shaft I5,betweenthedis'cs l'l 311C118;

The: inner end :of: the: crankshaft 15, within the crankcase $0 is provided withsacylindrical crank disc 2 I1 which serves to position the: crank shaft lfi withrespect tothe be'aring M yand which has mountedtherein a crank pin 221 The upper part! of the crank case l'll has an upwardly extending bossor projection 23, provided with an internally threaded portiom for the reception. of thelower externally threaded end 2510f a cylinder' 2'6'. The cylinder 26 1's also preferably formed in. one piece.

The exterior of: the cylinder 26': may peprovided with fins 21 'for heat absorption te prevent undue cooling or the enginei'upon-expansibn of the compressed gas, andto prevent condensation-of gas ormoisture upon 'expansionzof thegas during operation.

The cylinder. ZS-is adjustabl'e with respect-to thencrank ease 11) bythe engagement the threaded portions 24 and 25, and shell/in ad justed position by amen-mew engagement with the threaded portion 2-5 of the cylinder 26 and; if desired, the tube 33 -may-be of small" irr- Spaced downwardly from the upper end of the cylinder 26, a transversely extending wall 35 is provided which separates the space within the cylinder and below the cylinder head 3| into a fluid delivery and valve chamber 35 and a working chamber 31. The wall 35 preferably has a central opening 38 therethrough, with a portion of conical shape to provide a valve seat 39 and to permit the seating thereon of a sphericaljball 40. The ball 40 serves as an admission or inlet valve for the working chamber 31.

In the interior of the cylinder 26 and in the working chamber 31 below the transverse wall 35 a piston 4| is provided for reciprocation and for controlling the exhaust ports 29. Thepiston 4| has a wrist pin 42 therein which is connected by a connecting rod 43 to the crank pin 22. On the upper face of the piston 4| a push rod or abutment 44 is provided for moving the ball 43 from its seat 39 to admit fluid from the cham- .ber 36 for'expansion "in the chamber 31, as hereinafter explained.

With the piston 4| in a position with the push rod 44 out of engagement with the ball 40 and 'with gaseous fluid under pressure supplied to the pipe 33 and through the pipe 33 to the chamber 36, the engine is ready to be operated.

The shaft I is turned sharply by hand, such as by movement of the propeller, if a propeller is employed, and in the direction of rotation desired. The upward movement of the piston 4! causes the push rod 44 to engage the ball 40 and lift the same from its seat 39, permitting fluid under pressure from the chamber 36 to pass to the chamber 31 above the head of the piston M. The lower end 34 of the pipe 33 acts as a 'stop and prevents displacement of the ball 43. As the piston 4| moves downwardly, the ball 40, by reason of its weight and the removal of the push rod 44, is permitted to rest on the seat 39 and cut off further delivery of fluid to the chamber .31. The pressure of the fluid in the chamber 36 also aids in seating the ball 40.

The fluid thus delivered to the working chamber 31 then expands and the piston 4| is moved downwardly by the expansion to a position to open the exhaust ports 29 and permit the discharge of the expanded gas to the atmosphere. .As the piston 4| again moves upwardly, the push ;rod 44 again strikes the ball 40 and movesthe same from its seat 39 to permit the delivery of gas ;under pressure from the chamber 36 to the chamber 31, the ball 40 again seating as before .upon downward movement of the piston 4|. The ;,operation of the engine will continue so long as fluidis supplied through the pipe 33.

The chamber 36, particularly if the delivery pipe-.33 has a restricted bore, functions not only ,as a valve chamber, butalso as a storage chamber for pressure fluid and tends to eliminate fluctuations of pressure of the fluid admitted to the ,workingchamber 37.

If it .is desired to lubricate the engine, the piling may be readily effected through the exhaust ports 29 when the piston 4| is atthe top and at the bottom of itsstroke, respectively.

If it is desired to adjust the actuation of the valve 4|] to vary the speed, the lock nut 28 is loosened and the cylinder 26 turnedslightly with .respect to the crank case I0. If the cylinder 26 is moved downwardly with respect to the crank .c'ase lo, the length of the period of admission of gas is increased and the speed is increased, and .if the cylinder 26 is moved upwardly with respect to the crank case H], the length of the period of admission of gas is decreased and the speed of the engine is decreased. The cylinder 26 can be locked at the desired position of adjustment with respect to the crank case H] by tightening the lock nut 28.

We claim:

1. In an engine, a crank case having a crank rotatably mounted therein, a cylinder, a partition member in said cylinder separating the interior of said cylinder into a valve chamber and a working chamber, means for delivering pressure fluid to said valve chamber, said partition member being provided with an opening therethrough having a valve seat, a valve member for engagement with said seat, a piston connected to said crank and reciprocable with a fixed stroke in said working chamber, said cylinder having exhaust ports at one end thereof controlled by the movement of said piston, an abutment carried by said piston movable into and through said opening to engage said valve and move it from its seat to admit pressure fluid to said working chamber for actuating said piston, and means for adjusting the extent of opening of said valve member comprising an ad ustable connection between said cylinoer and said crank case.

2. In an engine, a crank case having a crank rotatably mounted therein, a cylinder, a partiuon member in said cynnoer separating the interior of said cylinder into a valve chamber and a working chamber, means for delivering pressure fluid to said valve chamber, said partitlon member being provided with an opening tneretnrougn having a valve seat, a valve member for engagement w1th said seat, a piston connected to said crank and reciprocable with a fixed stroke in said working chamber, said cylmder having exhaust ports at one end thereof controlled by the movement of said piston, an abutment carried by said piston movable into and through said opening to engage said valve and move it from its seat to admit pressure fluid to said working chamber for actuating said piston, and means for adjusting the extent of opening of said valve member comprising a direct threaded connection between said cylinder and said crank case, whereby the cylinder may be longitudinally shifted to change the location of the valve seat.

3. In an engine, a crank case having a crank rotatably mounted therein, a cylinder, a partition member in said cylinder separating the interior of said cylinder into a valve chamber and a working chamber, means for delivering pressure fluid to said valve chamber, said partition being provided with an opening therethrough having a valve seat, a valve member for engagement with said seat, a piston connected to said crank and reciprocable with a fixed stroke in said working chamber, said cylinder having exhaust ports at one end thereof controlled by the movement of said piston, an abutment carried by said piston for directly engaging said valve to move it from ,its seat to admit pressure fluid to said working chamberfor actuating said piston, and means for. varying the extent of opening of said valve and-controlling said admission of pressure fluid comprising, a direct threaded connection between said cylinder and said crank case, and a locking memb'ercarried by said cylinder for locking said cylinder and said crank case in predetermined adjusted positions.

4. In an engine, a crank case having a crank rotatably mounted therein, a cylinder having a threaded portion in direct engagement with a ;;th readed portion of said crank case, a partition member in said cylinder separating the interior of said cylinder into a valve chamber and a working chamber, means for delivering pressure fluid to said valve chamber, said partition being provided with an opening therethrough having a valve seat, a valve member for engagement with said seat, a piston connected to said crank and reciprocable in said working chamber, said cylinder having exhaust ports at one end thereof controlled by the movement of said piston, an abutw ment carried by said piston directly engaging said valve to move it from its seat to admit pressure fluid to said working chamber for actuating said piston, the threaded engagement between said cylinder and said crank case permitting a longitudinal shift of the cylinder to vary the extent of opening of said valve, and a lock nut in engagement with one of said threaded portions for locking said cylinder and said crank case in adjusted positions.

WILLIAM L. BROWN, 3RD.

WILLIAM L. BROWN, 4TH.

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

UNITED STATES PATENTS Number Name Date 734,533 Fouts July 28, 1903 862,518 Sowter et a1 Aug. 6, 1907 1,003,953 Simons Sept. 19, 1911 1,203,018 Larson Oct. 31,1916 1,605,075 Shaft Nov. 2, 1926 FOREIGN PATENTS Number Country Date 24,228 Great Britain Dec. 17, 1914 165,492 Great Britain July 11, 1921 425,325 Great Britain Mar. 12, 1935 48,397 Denmark Feb. 19, 1934

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