US433551A

US433551A - Gas-engine

Info

Publication number: US433551A
Authority: US
Publication date: 1890-08-05
Anticipated expiration: 1907-08-05

Description

(No Model.) 3 Sheets-Sheet 1.

A. SPERRY.

GAS ENGINE.

No. 433,551. Patented Aug. 5, 1890.

(No Model.)

3 Sheets-Sheet 2. E. A. SPERRY.

GAS ENGINE.

No. 433,551. Patented Aug. 5, 1890.

UNITED STATS PATENT OFFICE.

ELMER A. SPERR-Y, OF CHICAGO, ILLINOIS.

GAS-ENGINE.

SPECIFICATION forming part of Letters Patent No. J=33,551, dated August 5, 1890.

Application filetl December 12, 1887. Serial No. 257,716. (No model.)

T0 all whmn it may concern:

Be it known that I, ELMER A. SPERRY, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Gas-Engines, of which the following is a specification.

My invention relates to gas-engines, and my object is to provide a gas-engine in which many of the disadvantages adherent in the ordinary construction of gas-engines shall be obviated, as hereinafter set forth.

The invention is substantially illustrated in the aceompanying` drawings herein.

Figure l represents a diagrammatic view of an engine embodying' some of the principles of the present invention. Fig'. 2 represents a Vertical section through the cylinders and pistons, showing the mixing, governing', and igniting` devices and other features. Fig. 3 represents a detail, showing' one of the pistonrods and the piston of the pump and one of the packing-glands. Fig'. A represents a sectional view of a portion of the combustioncylinder, showing` the cored passag'es containing the piston-rods. Fg. 5 represents a side elevation of a complete engine for the purpose of showing the general arrangement of parts. Fig. 6 represents a section of the cylin ders and pistons through the exhaust-valves, showing means for driving the same, the ignitor, showing' also the check-valves leading from the pump to the combustion-cylinder, the defieetor for the inco'ming gases, and other features.

In these figures similar letters of reference refer to like parts throughout.

The letters A A indicate two combustioneylinders, fitted each with a plunger-piston A'.

A2 A2 indicate two single-acting air-pumps, with pistons A3 having a dliving-connection with a piston-rod a, as shown, which connects the pump-piston A3 to the connecting rod or pitman a' by means of the cross-head (L2 and 'gland or packing-box (L3. I

B indicates the erank of the power-shaft, and B' an auxiliary connection from the crankpin to a hell-Crank lever B2 for Operating the eXhaust-valves 'b Z), as will be more fully descrbed.

A forked lever is shown at b' for Operating the ignitors O C by contact with the crosshead 82 when in its extreme position.

Means are shown for holding' the lever b' in a central position when not engaged in either direction by the cross-head. Double Valves O' C' are shown between the air-mixture pumps A2 A2 and the combustion-cylinders. .p

O2 indicates the induction-port and valve for admitting` the mixture to the pump.

It| will be notieed that the eXhaust-Valves are operated by the contact of the stop B2 upon the rod C3, projecting from the lever B2, driven from the crank-shaft, as shown, the arrangement being' such that during' each alternate half of the revolution of the crankshaft each 'exhaust-valve Z) is opened land the other remains closed. Its stop B3 recedes from the eXhaust-valve connection.

By reference to Figs. 2, 3,4, and 5 the component elements l'epresented in the foregoing` diagram matic view may be easil y traced. In Fig.2 the two ends of both the oylinders and pistons are similar to each other, as Will be seen in the drawings. An elongatedcylinder A A2 A is bored of the same diameter at each end A A for about one-th ird total length. The middle one-third is of larger bore A. A cylindrical piston A' A' is turned to fit the two smaller bores at the ends of this eompound cylinder, and is provided with rings E2 for the purpose of packing the same. Centrally located upon this eompound piston is an annular projection (indicated byAS) turned to accurately fit the larger bore A2 of the compound cylinder. This projection serves as a piston for the pump or mixing cylinder. It is t-o this annular piston that the piston-rods a are attached. (See Figs. 3 and (i.) These pistons are secured to the opposite sides, or may be in any other suitable location. The stufling boxes or glands (L3 are provided at the end of a cored passag'e terininating in an aperture in the cylinder-head D3, leading from the miXing-cylinders, as shown. The pistons are secured to the 4cross-head (02, guided and attaehed by the pitman ct'min the usual manner. (See Fig. 5.) The three pistons are preferably made of a single casting provided with two cored passag'es D D', leading from the mixture-cylinder upon either side of the pis- ICO - contact-with its seat.

ton a to the combustion-cylinders. Each of these are provided With a suitable valve C', opening into a combustion-cyli nder. The preferred construction is shown in Fig. 2. This valve is mounted in a separate casting, which covers the end of the eored passage, and also covers the larger internal core, by means of which the casting is lightened. This casting is provided with a lever c and a weight c' on.

the opposite side of the f ulcrum 02 from that in contact with the valve C'. The momentum effect of this weight and lever upon the valve is opposite to that of said valve.

In Fi g. 6 two check-valves, coupled in series, connect the cored passages D D' with the combustion-cylinders. Guides of the usual sort are provided for the moving part of these valves, so that the motion of the piston cannot prevent them from seating properly. These valves are opened by the pressure of the mixture in the pump-cylinder a? The usual water-jaeket E is provided in the walls of the eombustion -cylinders and cylinderheads ZF. A tubular extension is provided to conduct the gases after they have passed the two valves c' c', the office of which will be more fully explained.

In Fig. 2 the eXhaust-ports Ware uncovered by the advancing piston in the last portionof its stroke, Whereas in Figs. 1 and 6 the exhaust-passages are controlled by valves Z).

In Fig. 2 the arrangement of inductionvalves is shown, and also the mixing-valves and devices at each end of the double-acting pump-cylinder A2 and in the passage C2. The induction-valve E' is provided. A stem E2 is guided suitably below, and at its lower eX- tremity is provided with an enlarged portion supporting the cushion E3, generally of rawhide. Immediately under these rawhide cushions are serews c, working in the serewthreaded caps e'. The upper ends of these serews are adapted to support the valve E' by engaging with the cushion enlargement E3 of the valve-stem before the valve is in The distance which the valve is elevated off its seat and supported in that position is determined by the height to which the screw is raised by turning the same iu its screw-tln'eaded socket c'. This is effected by any suitable governing device. The centrifugal governor F is shown mounted upon the crank-shaft B of the engine. The balls F' in being thrown from the center by the centrifugal force move the sleeve F2 along upon the shaft, vibrating the bell or crank lever Fi about its fulerum F, drawing lthereby the. rod f connected between said lever and the serew, thereby turning the screw c by means of the laterallyprojecting arm f2, securcd to the lower extremity of said serew e. The link F3 connects the two arms of the two serews and colnpels them to move simultaneously, thus preventing the valves at both ends of the cylinder from seating themselves each to the same extent as the other. As the piston A3 sweeps from one end to the other of the cylinderA2, (if the valves E' are supported above their seats,) the gases pass out partially by way of these valves,which communicate with each other on their under sides by passage G G G, so that the mixture which escapes before the advancing piston at one end is thrown into the cylinder at the other end and no extra tension is given nor power wasted. Under the center of this last-named passage is the combination-valve G', covering both the air-passages G2 and the gas passages oropenings G3, leading from a centrally-located inclosed cavity g, connected to the gas-supply. This eavity is covered by the cap g', provided at its center with an aperture for the valvestem Q2, provided with the cap and spring gg. The valve G' bears a circular collar at its onter periphery, which approaches very near the bore of the lower circular portion of the cavity G. Through this narrow annular passage the air and gas are compelled to pass, and are thereby mixed thoroughly. A wiregauze cap II is, however, provided to aid the mixing by cutting up the incoming mixture by means of its mesh. The valve G' lifts in response to any suetion of either end of the cylinder A2 from the common passage G, supplyiug thereby the amount passed out to the combustion-cylinder A' through the valve C'. This amount depends upon the closeness with which the valves E' are allowed to rest upon their seat-s. The cylinders are cast in two parts, having a joint at H' to facilitate in the manufacture.

The piston A3 receives the four piston-rods a a a a. (See Figs. 3 and 4.) These are secured, as shown, and pass out through cored passages and glands (L3 and attaehed to the cross-head (L2. The peculiar position of these rods necessitate a certain minimum differen eel of diameter between the two cylinders for obvious reasons. For some reasons this difference of diameter is too much and gives more area to the pump-piston than is required. The reason referred to is that the securing of the piston-red a to the piston A: should be so accomplished that sufficient metal is left upon the eXterior of the piston to provide strength against any excessive pressure or strain which the same is called upon to withstand. I obviate this by a releasing-passage 7b and h', (see Figs. 2 and 6,) by means of which the two are driven a short portion of their stroke, cou pled together, or short-circuited, whereby the compressing` side is then thrown into communication with the suction side, relieving the pressure entirely and establishing an equilibrium. This relieving-passage may be placed in mid-position 71, in the cylinder A2, (seeFig. 6,) or maybe divided and located at either extremity, which latter disposition I prefer in some cases. Iwould call attention,

IOO

IIOw

first, that at the end of this stroke the greatest flow of gases takes place between the cylinders A2 and A, necessitating the greatest opening of valve orrvalves C'. About this within cylinder A2 and behind valve C' before the end of the stroke, and allowing it to seat itself properly before the ignition takes place. Secondly, the escaping gases to the suetion side of the piston A3 quickly raises v the pressure and closes the induction-valve E' on the suction side, and at the same time releasing' the closed Valve E' on the compression side from the expanding gases, which fill the clearance spaces and passages and leaving' it free to respond to the least suction as soon as the receding piston A3 has covered the extremity of the releasing-passages h' h'. These may be of any convenient form; may consist of grooves, as shown, or holes maybe bored and piped or connected to each other to accomplish the same result, as will readily be understood. out that by the means of the releasing-passages h' h' the only transfer of the gaseous mixture from the pump-cylinder to the combustion=cylinder is in the centralportion of the back-stroke, and is fully accomplished before any considerable degree of compression has taken place in the combustiofn-cylinder. The advantage is evident from the fact that the pressure in the pump-cylinder must be equal and even slightly in excess of the pressure of compression in the combustioncylinder before the Valves will open to ad mit the gases, and if the maximum transfer be at the last of the stroke it will also be at the time of maximum pressure, which pressure will then act upon the added areas of both pistons and consume a large percentage of the power given off by the explosion of the gases in the combustion-cylinder. It is to this evidently-bad arrangement that the low efflciency of the present single cyele-eng'ines can be traced.

Having' thus described the main features the apparatus, by means of which the gaseous mixture is injected into the combustion-cylinder, I will next describe means of ig'niting same. The agent may be electricity, and may be prod uccd by any suitable generator, as the battery I, Fig's. 2 and 5. Any means for utilizing the current may be employedas, for example, the spark from an inductioncoil, high-tension generator, or a spark-coil I' may be included in the circuit, as shown in Figs. 2 and 5, which I prefer. To obtain a vigorous spark from a spark-coil, the circuit must be closed through the same for a certain period of time, then opened more or less sudde'nly. The spark oceurs between the points where the circuit is 'opened This spark-coil consists of a simple helix of Wire wound upon an iron core, and 1s essentially different from a Ruhmkorff or secondary in- It may be further pointed` duetion-coil. 'In addition to this fact, it should be remembered that it is expedient to `have the same generator and coil operate both ends or combustion-cylinders of the engine, and the following' means are shown whereby this may be accomplished. The means, however, are equally adapted for Operating the ordinary singleacting gas-engine.

In Figs. 1 and 2 the ignitor O is shown as being operated from a contact of the lever b' with cross-head (L2 when it is in its extreme positions. In Fig. G, however, it is shown as being operated by the movement of the piston, the opposite ends of the engine being precisely identical with each other as to the internal arrangement of the combustion-cyl inder, as will readily be seen. The arraugement of the igniting devices is such that, while the electrical current is closed through one ignitor, in the opposite end of the engine it remainsin open circuit. One pole of the battery I is connected to the metallie parts of the engine by wire 12, the other to the insulated electrodes 13 by wires fi, as shown. Through the center of the insulation I3 is a sleeve properly held within said insulation, which in turn is secured within the cylinder-head b3 in any of the well-known methods. `Within the sleeves i' are stems 1'2, Fig. 2, 2'3, Fig'. 6, which are placed in electrical connection with Wire i. Stems 2'2 engage at theirinternal extremity a bell-crank lever J, fulcrumed at J and adapted to make and break contact at its free end with stationary electrodes J 2, which are attached to the metal parts of the engine. The outer extremit-y of this stem 2'2 is connected with lever J 3, but insulated therefrom by thimlolej. A rod j' connects the lower extremities of these levers and levers b', adapted to engage the cross-head of the engine (L2 in the extreme portions of its oscillations.

Near the fulcrum j of the lever Jgfthere is a pointed lateral projection of this lever J3, which serves, in connection with the spring and roller attachment shown at j, to form a combination suited to retain the levers in their extreme positions. The fulcrum j is supported by the cylinder-head 113. The rod j' not only serves to connect the lever J3 to the actuating-levers b' but also to the lever J: at the opposite end of the engine, as illus- `trated,which is given an identical movcment.

The movable electrode i, however,protrudes from its opposite side into the cylinder, and the bell'crank lever J, at opposite ends of the engine, thoug'h given simultaneous movements will act oppositely, and when one is closing the other is in the act of opening the electrical circuit. Thus the ignitin'g-spark resulting from the separating of that pair of electrodes which bear the relation of closed circuit alternates from one combustion-cylinder to the other, as is required, the changes of the circuit-connection being' such that the one lever J completes the circuit and opens same before the other lever J eompletes the circuit, then this second lever J opens the IOO IIO

circuit before the first closes it again, and

so on.

In Fig. 6 I show the preferred construction of ignitor, which contains the stem 273, and is made adj ustable by a screw-thread. (Shown at itsv outer extremity.) The inner extremity is adapted to vmake and break the electrical circuit by the swinging of the lever K about the fulcrum K', which is in connection with the metallic portions of the engine, and therefore represents the opposite pole of the generator I. An upward. projection of the lever K engages with the pin K2, supported in sleeve K3' and pressed inward'by a strong spriu g L,thus holding the contact at the lower extremit).1 of the leverKsecure. Aweight L' is also shown projecting laterally from f ulcru-m K' and servesthe same purpose. The fulcrum K' of the lever K is supportedv by an-inde'pendent block L2, properly secured,.which is perforated near 'its'lower extremityfor the'purpose of supporting the rod L3. 'This rod passes through the lever K,,and is provided on either side of the same with buttons Z and Z', which` have convex faces turned toward the lever on itsopposite sdes.. It is thought preferable that the aperture in the lever K, through which the rod L3 protrudes, should' be so large that the rod does not touch it nor drag upon it, but operates said. lever solely by contact of the buttons Z and Z' upon its faces. The aperture Will be noticed to be near the fulcrum K', and there is preferably a slight amount of lost motion between the buttons and the lever. The rod L8 passes the entire length of the three cylinders, and is provided with similar'buttons Z and Z' and engages a similar le- Ver K at the opposite end of the engine. The length of this rod,however,is such that while' one lever K is in contact with its electrode 1'3 the other is held away therefrom, as is shown in Fig. 6.

A tube Z2 is supported by the moving piston, through which passes the rod L3. One or more glands Z3 may be provided, the packing of which serves also the purpose of securing thenecessary friction upon the rod L3.

A peculiar deflector, consisting` of a tubular casting M,acting in conjunction with the extension l of the passage leading to the airpump A2, serves, by means of its upwardlycurved extremity, to lead the incoming fresh gaseous mixture to the point where the spark is about to be produced, thereby securin g certainty of explosion. The particular shape shown is not necessary, as other shapes would doubtless suffice.

The exhaust-valve b is shown as operated from the crank-shaft in Fig. 1, and forms a contact with the moving cross-head in Fig. 6.

VThese valves are of the usual construction,

and-when adapted to be operated by a device common to each other are so connected that one will be closed while the other is open, and vice versa. To the exact devices for operating (shown in connection with these valves) I do not care to limit my invention; but any now proceed to state the operation of the several parts, which will be rcadily'understood from the foregoing description. The cycle of the engine will be readily understood to be as follows: The piston being at one end ofv its stroke, the compressed mixture is i gnited in one combustion cylinder and the exhaust valve or opening'is just being opened' in the other combustion-chamber, ar''d the pump piston or pistons, which move simultaneously in the two cylinders, or, what is the same in effeet, the two ends of the same cylinder, operate as follows: The one has just injected its gaseous mixture into the conibustion-cylinder taking'the i gnition the other is filled with the mixture, ready to transfer the same into the now exhausting combustion-cylinder. movement of the piston in one direction, during one-half the revolution of the crank-shaft,

; will transfer the mixture contained in one sideof the pump-cylinder A2 into the combusition-cylinder as the products of combustion i. are being exhansted, and in the other side of the pump-cylinder a fresh mixture of gas and fair is being drawn for the next charge in the combustion-cylinder,which it serves. The operation of the valvesE'andcombining-valve G' Will be readily understood from the drawings. These valves are of the usual construction and perform the usual function of the inductionvalves of an ordinary pump. The action of the governing device upon the screws e Will also readily be understood. The screw has a very stcep pitch and requires .only a few 'degrees of rotation to elevate the valvesufficiently from its seat to nullify to a large ex- `tent the transfer of gases into the combustiOn-cylinder. The operation of ignitors is extremely simple. The electrical generator I maybe used separately or in connection with the spark-coil, as shown. The ignitors are in multiple-are circuit, and are so mechanically coupled and actuated from the moving' parts of the engine, either by the moving piston or the cross-head or other moving part, as is fully shown in Figs. 1, 2, and 6. The coupling, in all cases, however, should be such that each ignitor closes the circuit andthen opens it upon it, upon which the first ignitor then closes the circuit. The entire force of the generator I is being spent upon one ignitor at a time. In Fig. 2 the contact with the cross-head (x2 changes the 1 position of the aetuating-levers upon each end of the cylinder, which vibrates the bellcrank levers J in the manner just described,`

one being open, while the other is in closed ci'rcuit relation. The opening or break of the circuit by these contacts interior to the cylinder produces a spark at the moment of the interception of the current, and thns ignites the gases. In Figs.1 and 2 this interception The IIO

is just previous to the finishing of the compression-stroke, and if the engine is a very high-speed engine the full effect ofthe explosion or expansion of the gases after ignition will take place only afterthe pitman has passed the center and has started to advance in the other direction; but if Athe engine-is employing a slower rate of speed the device shown in Fig. 6 is preferred, whereby the separation of the electrodes and ignition is prodnced after the erank-shaft has passed its center and is in the most favorable position for utilizing the immense strain produccd by the explo'sion of the gases, for, as will be readily understood, the intense heat, and therefore the energy of the exploding gases, is almost instantly absorbed into the cold walls of the cylinder and thereby wasted, and if the position of the crank can be such as to fully and instantaneously utilize this' energy a great saving will result. The causing of the electrodes to be separated by a dragging or frictional contact with the actuating element upon a moving part of the engine should be thoroughly understood, as it' forms a novel feature in the matter' of igniting` of the miXture in a gas-engine. The defiector shown in Fig. G serves in bringing the fresh gases into the most favorable position foi` ignition at each time the spark is prod uced.

I do not care to limit myself to the exact construction of the parts herein shown, 'and in many equivalent arrangements' could be provided for by carrying into effect the essential feature of my invention, which I have herein set forth.

I claim, and desire to secure by Letters Patent, the following:

1. In a gas-engine, a compound cylinder eonsisting of three cylinders, forming a single mechanical element, two, combustion-cylinders separated by the fluid-pump cylinder, Within which reciprocates a compound piston, in combination With passages connecting the cylinders, provided with valves opening` into the end cylinders from the middle cylinder.

2. A gas-engine having two combustioncylinders and a single fiuid-pumping cylinder, in combination with a piston for these cylinders, consisting of a single mechanical element.

3. In a gas-engine, the pumping part thereof, in combination with two self-acting eduction-Valves and induction-valves, the seating of which may be Varied.

4. In a gas-engine, a cylinder provided with two jacketed ends and an enlarged central portion, in combination with a piston provided with three portions adapted to reciprocate, respectively, in the three portions of the cylinder.

5. In a gas-engine, two single-acting combustion-cylinders separated by a third cylinder of larger bore, and pistons for the three said cylinders, in combination with ducts or channels cast in the Walls of the combustioncylinder, and piston rods attaehed to the 'fiuid-pump, and a power-shaft and connecting mechanism, substantially asshown and described, the arrangement being such that the combustion-cylinders deliver their power solely to the gas-pump, the power being transferred from the gas-pump piston to the powershaft.

7. -In a gas-engine, two opposite jacketed combustion-cylinders separated by a central cylinder of larger bore, thetwo jacketed cylinders being provided each With a plunger-piston bearing an annular enlargemcnt located centrally upon said piston, which enlargement forms a piston for the centrally-located cylinder, the three cylinders being separate and distinct from each other.

8. In a gas-engine, two pistons for the com bustion-cylin ders,in combination with apiston for the pump-cylinder, and a valve or valves contained within ducts connecting` the faces of like phase of the pistons which establish communication between the cylinders, and are contained within and move with said pistons.

9. In a gas-engine, a compound piston consisting of a cylinder with a concentric annular enlargement centrally located upon said cylinder, in combination with passages or ducts conn ectin g the faces of the said enlargement with the nearest combnstion-cylinders, and a valve or valves located in said passages.

10. In a gas-engine, two opposite jacketed cylinders separated by a central cylinder of larger bore, the two first being provided each with a plunger-piston, the two pistons connected by a central enlargement, forming a piston for the central cylinder, in combination with valves which are mounted in and move with said compound piston, opening toward the combination-cylinders, and are connected, also, to the central cylinder, substantially as and for the purpose specitied. w

11. In a gas-engine, a compound piston consisting of a cylinder, with a concentric annular enlargement ccntrally located on such cylinder, in combination with passages or ducts connecting the faces of such enlargement with the combustion-cylinde1's, and a valve or valves located in said passages.`

12. In a gas-engine, the combination of the valves O' O' and connecting-passages D and D', and cylinders A2 and A, substantially as for the purpose specified.

13. In the fluid-pumping part of a gas-engine, the combination of a valve with an adjustable screw-stop, whereby the seating of the valve is regulated.

14:. In the fluid-pnmping part of a gas-engine, the combination of an adj ustable screwstop,withthe induction-valve supporting same ICO IIO

1 6. In the double-actin g pum pin g device of a gas-engine, two induction-valves communicating between the cylinders upon the opposite sides of the piston, and a passage between said valves, in combination with regulatin g devices for establishing more or less permanent communication between the ends of the pumpingcylinder.

17. In a gas-engine, the combination, with the induction-valves of the pump, of a third valve leading to a passage common to both induction-valves, and concentrically-located air and gas passages adapted to be eovered by said third valve.

18. In a gas-engine, the combination of the valve E', valve G', air and gas passages G2 G3, and concentric passages G G, substantiall y as and for the purpose specified.

19. In a gas-engine, the combination of a valve adapted to cover air and gas passages, an inclosure leaving a contracted passage between it and the valve, and a diffusing medium located immediately in front of said eontraeted passage, substantially as and for the purpose specified.

20. In a gas-engine, a valve governin g the admission of the gasand air, of a recess in which said valve operates, and a collar upon said valve, which approaehes the walls of said reoess, and a diifusing medium near the recess so formed.

21. In a mixing device for gases in a gasengine, the combination of avalve governing the flow of said gases, a narrow circular reccss at the edges of the valve, and -a perforated cap over said reeess.

22. In a fluid-pump for a gas-engine, the combination of induction-valves, one at each endof the cylinder of said pump, with a common governing` system for simultaneously preventing both valves from closing.

23. In a gas-engine, an ignitoroperated by contact of a vibrating lever derivin g its motion either from contact with the erank-shaft or cross-head of the engine, the electric contact being interior to the cylinder and sustained (luring one-half ofthe revolution of the crank-shaft of the engine.

24. In a gasengine, and in combination with the ignitor thereof, a tubular projection or deflector secured within the cylinder and adapted to act in combination with a moving duet to receive the charge or a portion of the same coming from the fluid-pump.

25. In a gas-engine, adeflector adaptcd to lead themixturc to the ignitor, said dcfleetor consisting of a stationary and a moving element. i

- 26. In a gas-engine, adcflector consisting `foi` reducing the effective stroke-length of the piston.

30. In a gas-engine, the pumping` device therein, the stroke of which is substantially the same as and simultaneous with that of the combustion-piston,in combination with' -relief-passages at or near the end of the stroke. i

31. The pump-piston of a gas-engine secured to and moving with the combustion- -piston, in combination with passages whereby the transfer of fluid into the combustioncylinder is diseontinued just before the end of the stroke.

32. In a gas-engine, the piston of the gaspump secured to and moving With the piston of the combustion-cylinder, in combination with passages for cutting down pressure in the pump-cylinder in the latter part ot' the stroke.

33. A double-acting pumping portionV of a gas-engine, in combination with passages for establishing communication between the spaces upon the opposite sides of the piston While the piston is near at the extreme portions of its strole.

Sat. In a gas-engine, a piston which is common to both the combustion and pump cylinders, in combination with a valve opening toward the combustion-cylinder in a passage located between said two cylinders, and' relief-passagcs designed to bring the said valve to its seat before the end of the stroke of the piston communicating between the cylinders and passages.

35. In a gas-engine, a pumping device, the capacities of which are in excess of that required, in combination with relief-passages, so arranged that the transfer of gases can only take place during the central portion of the stroke of said pump-piston.

36. In a gas-engine, a pump provided with the relief-passages h' 7b' at or near its ends, substantially as and for the purpose specified.

37. In a gas-engine, two ignitors actuated at the expiration of the stroke thereof from a common source oppositely connected to each other and oonsistin g of movin glevers internal to the cylinder.

38. In a gas-engine having more than one combustion -cylinder, and in combination with the ignition-contact interior to each combustion-cylinder, a common source of elec IOC IIO

tricity, and multiple-are circuit-eonneetions froin said source to said ignitors.

39. Iii a gas-engine, tlie combination, with two ignitors, of the generator I, spark or selfinduction coil I' aiid electrical circiiits, and niovin g contact-levers interior to the coinbustion-chainber, aiid consisting of moving levers internal to the cylinder, snbstantiall y as and for the purpose specified.

40. In a gas-engine, and iii combination witli a generator or source of electrical energy, two electrical ignitors interior to two combnstion-cylinders coupled therewith iii multiple-are circuit.

etl. In a gas-engine, a' generator of cleo? tricity and circnits, in combination with two ignition-contacts interior to the two coinbustioii-cliainbers, one of which only maintains the closed circuit relation at a time.

42. In a gas-engine, a generator of electricity and niultiple-are circuits, in combinatioii with two ignition-contacts interior to two combnstion-chambers, wliich inake and break the electrical circuit alternately.

43. In a gas-engine, a generator of electricity and multiple-arecircuits, in combinatioii with two igniting-cont-acts interior to two coinbustion-clianibers, and actnating devices for causing one of said contacts to close the electrical circnit and break the same before the otlier closes said electrical circuit.

44. In la gas-engine, the combination of electrical generator-circuits, twoignition-coiitacts interiorly disposed to the cylinder, and actiiating devices wliereby the circiiit of the generator is alternately completed through first one and then the other of the contacts.

45. In an igniting device for a gas-engine, levers interior to the coinbustion-cylinders foriniiig a part of an electrical circuit, operating in conjunction with a contact interior to each of the combnstion-cyli'ndei's also iii'- cluded in the electrical eircnit, in combination with the moving part of the engine, and connecting devices for holding' said lever from eiigagement with said contact during oiie-lialf of the revolution of the crank-shaft.

46. In an ignitor for a gas-engine, two levers connected and moving siinultaiieously interior to two combustion-cylinders by reason of contact With the moving part of the engine.

47. In a gas-engine, two separate cylinders, each provided with a vibrating lever, and a single rod connecting the levers,whereby the levers are vibrated simultaneously internal to each cylinder.

48. In a gas-engine, an ignitOr-actnating part sustaining a sliding frictional contactwith tlie moving parts' 49. In an ignitor for gas-engines, the vibratinglever, in coinbiii ation Wit-li a rod which sustains a sliding frictional contact or engageineiit with a moving portioii of said engiiie.

50. In an ignitorfor a gas-engine, avibra'c iiig lever, in combination with a rod which snstaiiis a sliding or rnbbing frictional engagementwith the movin g portion of said cngine and contact part or parts of the rod bearl ing such a relation to the lever as to provide a small open space or lost moi ion between r the lever and rod.

51. In an ignitoi' for a gas-engine, avibratiiig lever, in combination with a rod which contains a rubbing frictional engagement with a inoving portioii of the engine and passes-near said lever for engagement with same, snbstantially as and for the purpose` specified. t

52. An igiiitor for a gas-eiigiiie, consisting of two vibrating levers interior to two combustion-cylinders connected by a rod.

53. An ignitor for a gas-engine, consisting of two vibrating levers iii separate coinpartnicnts, in combination with a rod which eX- tends from one coinpart-nient to tlie other.

51h Agasengine having two cylinders con' nected by a common piston, in combination with 4a vibrating lever located within eacli cylinder and connected by a rod which sustains a frictional engageinent with said piston.

55. In an ignitor for a gas-engine, two levers, in combination with a rod actnating the same, whicli rod passes near, but not iii contact with, said levers, and is provided with stops adj acent to and upon the opposite sideof said levers, substantially as and for the purpose specified.

56. In an ignitor for a gas-engine, the coiii-4 bination of a vibi'ating lever sustaining an electrical connection with the inetallic parts- 57. In an ignitor for a gas-engiiie, the combination, with two vibrating levers interior to two combustion-cyliiiders and connected to each other, of two insulated contacts and a common electrical generator, substantially as and for the pnrpose specified.

58. In combination with an ignitor fora gasengine, a contact in each of two or more combustion-cylinders of the engine, a single-spark or self-induction coil, and a generator for the same, each contact adapted to close the circuit of the coil, oiie of sucli interior contacts only inaintaining the closed-Circuit relation at a time.

59. In an ignitor for agas-engine, two simnltaneously-vibrating contacts interior to separate eylinders,connected in like relation in coniiection with insulated electrodes or contacts, between which both levers are located, and a coniinon generator or source of electricity.

(30. In a gas-engine,the combination of levers 7a 7.1, rod L, and moving part of the engine,

-snl:stantially as and for the pnrpose specified.

IOO

IlO

01. In an electrical ignitol', the combination 04. In an ignitol' for a gas-engil'le, the level' of level's K K, l'od L3, and Springs L L. k, beal'ing the Weight L'.

(32. In an electrical ig'nitol', the combination 65. In a gas-englne, the comblnatlon of a of the level' K, rod L3, spring L, and contact piston l'od 01' l'ods, a piston A3, col'ed dnct 01' 15 5 2'3, sllbstantially as and for the pnl'pose specipassag'e 'within the walls of the cyllndel',

fied' l gland a3, and cylinder-head 113, substantlally 63. In a gas-engine,in combination Witll the as and ful' the pul'pose specified. level' K and l'od L3, casting L3, adaptcd to ELMER A. SPERRY. support the level' and also the extl'elnty of Witnesses: Io the l'od, substantially as and fol' tlle pul'pose E. F. VVALLACE,

specified. CORA L. CADWALLADER.