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Publication numberUS1076172 A
Publication typeGrant
Publication dateOct 21, 1913
Filing dateMar 30, 1903
Priority dateMar 30, 1903
Publication numberUS 1076172 A, US 1076172A, US-A-1076172, US1076172 A, US1076172A
InventorsJames Todd
Original AssigneeJames Todd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Explosive-engine.
US 1076172 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

J. TODD.

EXPLOSIVE ENGINE.

APPLICATION FILED MAlLao, 1903.

Patented Oct. 21, 1913.

3 SHEBTS'SHEET 1.

INVENTOR WITH ESSES ZHQL gil/42;@

(olmnum PLANomzAvn cn.. WASHINGTON, n. c.

J. TODD.

EXPLOSIVE ENGINE.

APPLICATION FILED MAImo, 190s.

Patented Oct. 21, 1913.

3 SHEETS-SHEET 2.

jana ym/@MU d Patented Oct. 21, 1913.

3 SHEETS-SHEET 3.

INVENTOR WITNESSES JAMES TODD, 0F SEWICKLEY, PENNSYLVANIA.

EXPLOSIVE-ENGINE.

Specification of Letters Patent.

Patented Oct. 21,1913.

Application led March 30, 1903. Serial No. 150,108.

le it known that I, Jxnns Toon, ot' Sewicliley, Allegheny county, Pennsylvania, have invented a new and useful Explosive- Engine, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which Figure 1 is a top plan view showing one Vlorin of my improved engine system, with the casing coverl removed; Fig. 2 is a sectional side elevation of the same; Fig. 3 is an end elevation partly in section on two diiterent planes of the engine valves; Fig. l is a section on the line IV--IV of Fig. 3; Fig. 5 is a section on the line V-V o' l `ig. I; Figs. (5 and 7 are detail views oi' the exhaust cam; Figs. S and E) are detail views et the supplemental exhaust cani; Figs. 10, 11 and 12 are detail views of the admission cani; Figs. 13 and 11 are detail views of the spiral gears for operating the valves, and Figs. 15 and 1G are detail views of the inlet port for the air pump.

My invention relates to the class of explosive engines, and is designed to provide ar engine of this type which may be reversed and which shall be self-starting, balanced and noiseless in its action, and non` centering.

To this end the invention consists in combining' the explosive motor or gas engine cylinder or cylinders with an auxiliary doublc-acting cylinder or cylinders also connected to the main shaft, this auxiliary cylinder operating in the manner of a steam engine cvl iuder.

lt also consists in means for supplying the products trom the gas engine cylinder :.r cylinders to the double acting cylinder preferably through an intermediate tank. Also in ln'oviding connections tor supplying the auxiliary cylinder with the exhaust products from the gas engine to actuate the piston therein, or by changing the said connections and actuating the piston from another source it may be used as a pump to exhaust the gas engine under a partial vacuum.

The invention further consists in providing a casing for the engine in which a pai'- tial vacuum may be maintained, in an arrangement of the cranks for the main and auxiliary cylinders` in reversing mechanism, and in the construction and operation of the parts as more fully hereinafter described and claimed.

In the drawings, I show a forni ot' my invention wherein two parallel gas engine cylinders are employed, each working on the tour cycle plan, and one exploding alternately with the other; in connection with an auxiliary cylinder of double-acting steam engine form. In these drawings 2, 2 are the parallel gas engine cylinders having pistons 3, with connecting rods l, 1 leading to a common crank on the main engine shaft 5. The auxiliary cylinder G is set at one side and is )rovided with a piston 7 whose piston rod 8 is connected to a cross-head 9 with connecting rod 10 extending to a crank 11 on the shat't 5, which crank is about 5)(1 degrees back of the gas engine crank. The was engine cylinders exhaust through valves lereinafter described into a main exhaust pipe 12 leading to a closed receiver 13, or through a secondary exhaust-pipe 14 into a niutiicr 15, and thence to the open air. Leading from the receiver 13 to the valve chest 17 of the auxiliary cylinder is a supply pipe 1G which is provided, preferably near the receiver, with a three-way valve 1S arranged to connect the receiver to the chest 17, or to close this connection and at the same time open the receiver to the air through the side outlet 19.

In starting the engine compressed air is used, this being supplied from a tank 2() from which pipe 21 leads into pipe 16 between thc valve 18 and the auxiliary cylinder. The pipe 21 is provided with a controlling valve 22 having an operating lever 23 which is normally held in the position shown in ull lines in Fig. 1 by a spring 24. The valve 1S is provided with an operating arm 25 to which leads a pivotal link 2G extending to a convenient point for the operator, and on the link 2G is a pin 27 which is arranged to contact with the arm In starting the engine the link 26 and arm 25 are moved into tl position shown in dotted lines in Fig. 1. The first part of this movement closes the connection between the receiver 13 and the pipe 16, and opens the receiver to the atmosphere, and the further movement causes the pin 27 to act upon and open the valve 22, thus Supplying compressed air to the valve chest 1.7. The coinpressed air passing through pipe 16 enters the valve chest 17. 'from which the supplyports QQ lead into the cylinder 'lhe valve ehest contains the balanced piston valve il!) ot' ordinary steam engine type and through which the exhaust passes into the outlet pipe 29. The valve stem 3() is connected to an ordinary reversing link gear 3l actuated by eccentrics the link being shifted through the lever and link system indicated atI 35E in Fig. This portion ot the apparatus is ot' ordinary type. and will not need turther description.

The eompressed air tank is supplied through pipe $34 leading from the upper rear end ot the air pump 35, and the air is taken in through the lower pipe 3G at the rear end ot this eylinder. The pipes 34 and it? are provided with cheek valves ot ordinary torm. The piston 3T ot this air pump cylinder is arranged in tandem with the auxiliary cylinder 6 and its piston-rod 38 is formed as a continuation of the piston-rod 8.

tn orderl to red uee the noise ot the running parts ot the engine lY preferably inclose the eylinders in a easing S9, this easing having a removable top cover-plate or plates, and hand-heles or man-holes with closures; and within this easing l preierably maintain a partial vacuum by means of the air pump cylinder The tront end of this cylinder is provided with an exhaust-pipe 40 which leads outwardly through the easing to the open air and is provided with a downwardly seating check-valve 4l. l have shown the inlet-valve at the front end of this cylinder in Figs. 15 and i6. This valve consists of a valve disk 452 covering inlet ports 43 opening through the cylinder-head, and itself containing non-registering ports 44. This disk is formed as part ot a hollow sleeve 45 whieh extends through the head and is se` cured at its outer end to the stutling box 4G for the piston-rod. The friction ot' the piston-rod will move this inlet valve inwardly and open it as the suction stroke begins and then close it on the beginning of the opposite stroke, the air being forced out through the pipe 40.

The gas engine cylinders are supplied from a gasolene tank 4T, trom which pipe 48 leads to the earbureter 49. The pipe 50 leading from this carbureter is connected to the branch supply-rapes 5i one for each of the eylinders 2.

l will now describe the valves and passages controlling the inlets and outlets for the engine cylinders. These are more clearly shown in Figs. 3, 4 and 5, and are` the same tor each cylinder. In these igures 52 is a passage leading outwardly through the rear cylinder-head and provided with two upper ports controlled respectively by upwardly seating exhaust valve 53 and inlet valve 54. The valve 53 controls the main exhaust passage 5o which leads around the inlet passage 56 and extends under the check valve 5T, see Fig. Y and also under the suppleinental exhauslfvalve 5S, The eheek valve 5T isa downwardly seating valve leading to the main exhaust-pipe l2, while the valve 58 controls the passage to the secondary exhaust 14. lt is evident that the exhaust products from the cylinder cannot pass outy through the secondary exhaust valve except when the main exhaust valve is opened. The connections to the valve 53 and the valve 5S are so arranged that the main exhaust-valve is opened at the end of the explosive stroke and remains open throughout the succeeding back stroke of the piston. lllhen pressure is to be maintained in the receiver and the lead ot the valve QS) is such (for example A; lead) that the anxiliary cylinder acts as an expansion cylinder, the exhaust passes out against the back pressure and durin the back stroke the products will only tow through the check valve into the receiver. At the end of this back stroke there will be exhaust gases remaining in the clearance spaces under pressure, and these would cause trouble in admitting the next charge. and it under suficient pressure would blow back through the carburetor. This dittieulty l overcome by the supplemental exhaust which is timed so as to open slightly before the end ot this back stroke.y and allow it to pass out through the pipe 14, and inutile l5. The main exhaust valve closes at the usual time and cuts oif the passage to the supplemental exhaust, whose valve may be closed at any time before the next opening ot the main exhaust.

The inlet-valves 54 are moved downwardly at the proper intervals to admit the charge to the passage 52, as in the ordinary type, l have shown all ot these valves, except the check valve .57, as heilig closed by springs 5) surrounding their stems G0, the stems being forced down against springpressure by cams acting upon the friction wheels 6l.

I will now describe the connections by which the three mechanically moved valves for each cylinder are actuated. The main engine shaft 5 carries a spiral gear 62 intermeshing with a spiral gear G3 upon a longitudinal shaft G4. The gearing gives this shaft G4 a motion of two to one relative to the main shaft, and it in turn is connected by spiral gearing (35 with a cross-shaft 66 which extends directly over the valve stems of the main and supplemental exhaust valves.

In Figs 6 and i', I show the cam for actuating the main exhaust. The fact. that the engine is reversible necessitates a peculiar construction oit the several cam mechanisms in order that they may operate the valves at the proper time t'or forward or reverse motion of the crankshaft. ln all of the views showing the cams l show them in full linesv in the position which they occupy near the end ol the explosion stroke as the main exhaust is about to open. The cam (3T for operating the main exhaust is secured to the collar 68 which loosely surrounds the shaft and is forced by a spring (3S) toward a collar 7() which is keyed to the shaft. The collar (SS has side lugs 7l which are adapted to engage lugs 'T2 projecting from 'the keyed collar Tt), and in the position shown. with the engine running` countcr-clockwise the lugs T2 engage the cam and force it around in the direction indicated by the full lined arrow of Fig. thus depressing the main exhaust against the action of this spring.

dien the engine is reversed. the lugs ou the cam and the feed collar are so arranged that the shaft will turn in the opposite direction through an angle of about 9() degrecs before the lugs engage each other again; and this will open the main exhaust at the proper moment when the engine is running in a clockwise direction. have shown in dotted lines in Fig. t3 the position of the cam in such case. the direction of rotation being indicated by the dotted arrow.

In Figs. 8 and 9, I show the cam i3 for the su )pleinental exhaust, which extends through a little more than 19t) degrees of its circuinference. rthis cam docs not need to be .shifted in reversing. since it is only nec essary that the supplemental exhaust be closed at some time between the closing of the niain exhaust and the next opening of the main exhaust.

ln Figs. it). ll and l2. l show the arrangeinent' of the admission cam. This cam 'il is connected with a shaft T5 which extends varallcl with the shaft tl and is eeared to 7G and T'. the wheel TT being lcose on the shaft T5. The cani il is keyed to the shaft T5 and the gear-.vheel TT has a side lug T8 which engages a lug T) projecting from a collar St) which is splined to an intermediate sleeve Sl on which the gear wheel loosely rotates` and `which in turn is keyed to the shaft T5. Yl`he sleeve di has a ring or disk S2 at one end and a collar S3 at the other end. a spring Si being placed between the collar 83 and the outer collar Si). 'l'hese figures show in full lines the position of the cam and the lugs when the pistons are in the pcsition shown in Fig. l and the engine shaft is rotating in a counter-cloekwise direction. lvlien reversed the gear wheel TT will turn around the sleeve Si. through an arc of about 2T() degrees, until it engages the other side of the lug T8.

lt will be noted that a separate cani mechanism is provided on the shaft (lo for each of the separate engine cylinders. while the single cam-mechanism of' Figs. 1t). 1l and l2 operates the admission valves for both cylinders. see Fig. l. This is the rea-- son for using a dili'erent mecnanisni for the it by gear wheels inlet valve cam .from that for the exhaust cam. and if two cams were used for the inlet valve they could be similar in arrangement to that for the exhaust valve, except for the difference on the arc through which the slip occurs.

The sparking plugs S5 are shown as wired to brushes acting on the circuit breaker Sti secured to the extension of the shaft (il with the usual connections to the battery and induction coils shown at ln order to shift the brushes on reversing to give the saine point of ignition while thc niain shaft is turning in the opposite direction. l preferably pivot the link connection to a bell crank St) which is nnninted on the top ot' the casing cover and is arrangetil to be engaged by pins 90 upon the reversing ccnnections for shifting the links. in this way l automatically shift the brushes when the engine is reversed thus keeping' the point of ignition the saine.

.l have shown the circulating pulnp Ul as driven by the shaft (il and connecting with the cooling coils U2 and the pipe SEZ- leading to one cylinder. the pipe l conducting the cooling fluid back from the other cylinder to the pump. I have also illustrated a driv ing' shaft tto haring a gear wheel t intermeshing with an eccentric gear wheel 0T mounted on the common crank for both cvlinders, thus avoiding a second crank, The eccentricity of the gear-wheel 9T gives the saine action as though an ordinary gear wheel were mounted on the saine axis as the engine shaft. The wheel Slo` together with a wheel 98 are mounted on a collar surrounding' shaft 953. the whee 918 inlermeshing with wheel in) on a counter shaft having a pinion lttl interineshing with a toothed wheel itil loosely snrroui'iding the shaft 95. yl"he clutch lili is arranged to throw in either ser of gears. and thus give different speeds. rl`he shaft 95 projects to the exterior of the closing casing and carries thc chain or other wheel 103 lor driving the automobile axle or other shaft to be driven.

In the operation of starting the engine the rod 2G is actuated to close the receiver connection with the pipe 1G and connect this pipe with the compressed air reservoir. Daring this niovenient of the rod the receiver is first connected to the open air through pipe l) and then at a later part of the movement the valve is opened, thus supplying compressed air to the valve chest of the double-acting cylinder. The piston of this double-acting cylinder will thus be actuated in the saine manner as an ordinary steam engine. and will rotate the main engine shaft`r its own valve bein;l properly actuated through the,` eccentric. n explosive charge will thus be compressed in one of the gas engine cylinders, and as soon as the explosion takes place the operator will shift the link QG to close the valve J2 and aetuate the valve 1S to connect the receiver with the pipe 1G. The main exhaust from the {Ias engine cylinder will pass into the receiver and thence be taken to the double-acting cylinder. At the same time air will be pumped into the compressed air reservoir, and the same pump cylinder will act to exhaust the air from the interior of the casing' to produce a partial vacuum which will deaden the noise of the moving parts within this casing.

In using the apparatus with a pressune in the receiver above atmospheric pressure, the burnt products from the explosive en- ;.ine cylinders expand within the doubleactinp cylinder, and the pressure of these products is thus converted into work, utilizing the power. instead of exhausting these products directly into the atmosphere. These gases are preferably expanded to at or near atmospheric pressure, thus obyiating the noise of the exhaust. In this connection it is desirable to take the exhausted gases from the gas engine cylinder into pipes of sntlicient size to a it as a reservoir, or preferably as shown, into a small tank, though the connection may be direct. ln startine, the compressed air acts through the auxiliary cyliiuler to drive the plungers of the las engine icylinders until they discharge their contents and take in fresh fuel when the electric contact is closed, the compressed air is shut off from the auxiliary cylinder. the compounding); tank is closed. and the valve opened from it to the auxiliary cylinder.

The engine is self-starting whether it is run forward or back yard. lnasniuch the pressure supplied to the auxiliary cylinder is practically uniform, th(` speed of the ejas engine pistons will be made more uniform. this preventingV to a large extent the variation of speed between explosions, The noise of the exhaust is prevented by the auxiliary cylinder which expands the frases to substantially atmospheric pressure, except as to the small amount in the clearance spaces, which is discharged into the muffler. rPhe noise of the moving parts of the engine is absorbed in the partial vacuum within the casing'. which casing also protects the engine from dust. The crank of the auxiliary cylinder cannot become centered on account of the different angle of said crank from that of the gas engine, the cylinders and the partial vacuum in the engine case, yEhe gas eneinc pistons being subject to the pull or suction of the vacuum and operating together, a vacuum pull on the njas engine pistons is exerted, so that when the power is cut olf these pistons will be drawn to their extreme forward position, so that by placing the crank of the auxiliary cylinder so that it is not in the same position, nor opposite to the position of the main crank, the auxiliar)r crank cannot become centered. lf the engine intended to reverse, the auxiliary crank should be nearly ninety degrees to one side of the main crank; but if the engine is to run in one direction only, then the auxiliary crank should be somewhat less than 180 degrees back of the main crank, thus giving: the auxiliary piston the greatest possilfle stroke before its valves close, and the tty wheel carries it over the center.

The cylinder t3 may be used as a pump to remove the exhaust gases from the main cylinder, thus creating; a partial vacuum in the exhaust receiver or tank. rThere would also be a more powerful explosion, due t0 a greater portion of the burnt gases being removed, giving less interference with the full power of Ythe explosion, and admitting a larger charge, as a portion of the inert or burnt gases are removed; and further the partial vacuum would exert a pull on this side of the piston during its exhaust stroke thus pulling it on this stroke and increasing the working' pressure of the gas engine piston. ln this case the lead of the valve 29 would be increased (for example lead) so that the volume taken into the cylinder (l would be greater than the exhaust from the gras engine cylinders 2, and create a partial vacnum in the receiver l?) and pipe i6. ln either case, whether the auxiliary cylinder is used as a motive cylinder or as a pump, it may bc connected direct to the main explosive cylinder or cylinders, without the intermediate reservoir or pipe systei'n.

The advantages of my invention result from the use of a double-acting auxiliary cylinder which makes the engine reversible, and which may be used either as a pump to mechanically exhaust the burnt gases or as a motive cylinder, and allow further expansion of the (gases, by adjusting the lead of the valve therefor. The auxiliary cylinder will not center owing to the partial vacuum in the case. which vacuum also prevents the noise of the working parts. It will also be readily understood by those familiar with the art. that the main cylinder may be. double acting'. and the auxiliary cylinder may be single acting.

Many other changes may be made in the fet-in and arrangement of the cylinders and connections, the relative arrangement of the parts, etc., without departing from the spirit and scope of my invention` as defined in the appended claims.

l claimw 1. In an explosive engine, an explosive c vf'linder having,Y a valve-controlled exhaust, an auxiliary cylinder' connected to the exhaust for receiving the burnt gases therefrom, a piston in .sa-id cylinder. connections between said piston and a moving' part of the explosive enginen a secondary exhaust for said explosive engine through which some of the spent gases may be forced by the movement of the piston, and means for controlling said exhaust, substantially as described.

2. In an explosive engine, a single-acting primary explosive cylinder having a valvecontrQlled exhaust, connections or supplying a mixture of air and fuel to the cylinder, means for exploding the mixture in the cylinder, a double-acting auxiliary cylinder connected to the valve-controlled exhaust, a piston in said cylinder, connections between said piston and a moving part of the explosive engine, the burnt gases from the explosive cylinder passing from the exhaust to the auxiliary cylinder, a secondary exhaust for said explosive engine through which some of the spent gases may be QICed by the movement of the piston, and means for controlling said exhaust, substantially as described.

3. Inan explosive engine, a single-acting primary explosive cylinder provided with a valve-controlled exhaust, connections for supplying an explosive mixture to the cylinder, means for exploding said mixture in the cylinder, a reservoir connected with the valve-controlled exhaust to receive burnt gases therefrom, an auxiliary cylinder connected to the reservoir, a piston in said cylinder, and connections between said piston and a moving part of the explosive engine, the burnt gases from the explosive cylinder passing from the reservoir to the auxiliary cylinder, a secondary exhaust for said explosive engine through which some of the spent gases may be forced by the movement of the piston, and means for controlling said exhaust, substantially as described.

4. A gas engine having a plurality of cylinders, a case inclosing the cylinders, a pump arranged to maintain a partial vacuum within said case; substantially as described.

5. In an explosive engine, an explosive cylinder having an exhaust, an auxiliary cylinder' arranged to receive the burnt gases from the exhaust, a piston in said auxiliary cylinder, a valve arranged to cut off the exhaust connection to the auxiliary cylinder and open said exhaust to the atmosphere, an air compressor arranged to be actuated from a moving part of the explosive engine, a compressed air tank communicating with the air compressor, an air supply connection from the tank to the auxiliary cylinder for moving the piston in the latter, means to open and close said connections, and mechanical connections between the auxiliary cylinder piston and the explosive engine piston for starting the explosive engine; substantially as described.

6. In an explosive engine, an explosive cylinder, a reservoir arranged to receive the burnt gases 'from the cylinder, an auxiliary cylinder arranged to receive the burnt gases from the reservoir, an' air compressor, a compressed air tank communicating with the compressor, and mechanism for connecting and disconnecting the air tank and the burnt gas reservoir with the auxiliary cylinder, a piston in the auxiliary cylinder connected with the main engine piston for starting the same, and said connection serving to connect the auxiliary cylinder piston to the Ipiston of the main engine to operate them in time with each other; substantially as described.

7. In an explosive engine, an explosive cylinder having an exhaust, an auxiliary engine having a cylinder, a piston in said cylinder connected with the main engine and in communication with ,the exhaust for the main engine arranged to receive the burnt gases therefrom, rlink gear for reversing the auxiliary engine, mechanism for shifting the valve mechanism of the explosive cylinder, and a connection between the link gear and the valve-shifting mechanism .of the explosive engine to reverse the link gear when the auxiliary engine is reversed, substantially as described,

8, In an explosive engine, an explosivecylinder having an exhaust a sparking device for the explosive cylinder, an auxiliary engine having a cylinder, a piston in said cylinder connected to the main engine and having a valve chest in communication with the exhaust for the lnain engine arranged to receive the burnt gases therefrom, link gear for reversing the auxiliary engine, and means for automatically reversing the sparking device when the engine is reversed; substantially as described.

9. An explosive engine cylinder, a casing arranged to inclose the cylinder and its Working parts, a pump arranged to create a partial vacuum within the casing, and a compressed air reservoir, said pump being arranged to discharge into the air reservoir; substantiallyy as described.

l0. An explosive engine cylinder, an auxiliary cylinder arranged to receive the burnt gases therefrom, a casing inclosing the cylinders and their working parts, a pump arranged to create a partial vacuum Within the casing, and a compressed air reservoir' connected to the auxiliary cylinder, said pump being connected to the driving gear and arranged to supply air to the reservo-ir; substantially as described.

l1. An explosive engine cylinder having a piston connected to the main driving shaft, an auxiliary cylinder, a piston within said cylinder connected to acrank on the main shaft at an angle to the main crank, a case surrounding the cylinders, and a pump for maintainingY a partial vacuum within said case, said pump/b eing actuated by the piston Within the auxiliary cylinder; substantially as described.

12. An explosive engine, a case surround` ing the engine, and means for maintaining a partial vacuum Within said case; substan' tially as described.

13. The combination with an explosife engine, of an exhaust reservoir for the explosive engine, an auxiliary cranking engine for the main engine, a supply pipe leading from the exhaust reservoir to the cranking engine, an air pump actuated by one of the engines, a storage tank connected to the air pump, a supply pipe leading from the air tank to the supply pipe for the auxiliary cranking engine, and a hand actuated controller for cutting off the connection between the air tank and the cranking engine and for opening the connection between the air tank and the cranking engine; substantially as described.

14. In an explosive engine, an explosive cylinder having a valve-controlled exhaust, a piston in the explosive cylinder, an exhaust reservoir, an auxiliary cylinder having a valve chamber in connection With the exhaust reservoir, valves in said valve chamber, a double acting piston in theA auxiliaryvcylinder, a crank shaft connected to the pistons in both cylinders, and means connected to the crank shaft for operating the Valves for both cylinders; substantially as described.

15. In an explosive engine, an explosive cylinder having a valve-controlled exhaust, a piston in the explosive cylinder, an auX- iliary cylinder having a valve chamber in connect-ion with the explosive cylinder eX- haust, valves in said valve chamber, a double acting piston in the auxiliary cylinder, a crank shaft connected to the pistons in both cylinders, and link gear to shift said valve connections to reverse the movement of the crank shaft; substantially as described.

In testimony whereof, I have hereunto set my hand.

JAMES TODD.

I/Vitnesses:

C. P. BYnNEs, H. M. CORWIN.

Gopies o! this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5847470 *Oct 31, 1996Dec 8, 1998Mitchell; Herman RooseveltAuxiliary motor drive system
Classifications
U.S. Classification60/613, 123/198.00R
Cooperative ClassificationF02B33/06, F02C6/16