US1716627A - Engine starter and generator unit - Google Patents

Description

June 11, 1929. H. FORD ENGINE STARTER AND GENERATOR UNIT Filed Aug. 18, 1926 2 Sheets-Sheet l m YENTOR.

ATTOEWY June 11, 1929. H. FORD 1,716,627

ENGINE STARTER AND GENERATOR UNIT Filed Aug. 18, 1926 2 Sheets-Sheet 2 INVENTOR.

E g 'ORNEY.

Patented June-11, 1929.

UNITED" STATES PATENT OFFICE.

HENRY FORD, OF DEARBORN, MICHIGAN.

- ENGINE STARTER AND GENERATOR UNIT.

Application filed August 18, 1926. Serial No. 129,972'

' pensive construction.

Still a further object. of my invention is to provide an internal combustion engine having an electric motor associated therewith, for the purpose of starting the engine,

' and to provide in connection with such motor, means for automatically connecting and disconnecting it with some portion. of the engine when the starting motor is actuated and when the engine is running under its own power respectively.

Still a further object of my invention is to vprovide an engaging device of the type described which may be mounted upon the front cross member of the car frame and connected to the crankshaft of the engine so as to form an extension thereto.

Still, a further object of my' invention is .to provide an engaging device of the type described which has a gear fastened to the engine crankshaft, thru an extension, and ratchet pawls, or dogs fastened on said gear and acting upon a ratchet wheel which is connected thru a gear train to the starting motor so that when current is supplied to the motor, then that the ratchet connected to the starting motor will engage with the pawls connected to/ the engine; but when the engine starts running under its own powerthen the pawls thru centrifugal action will disconnect themselves from the ratchet wheel connected to the starting motor.

Still a further object of my invention is to provide an engine starter and generator unit which will be reasonably free from noise when operating. In this connection it will no doubt be understood that one of the types of starter drives generally used is made up of a small pinion mounted on the starting motor shaft, the teeth of the pinion meshing with the teeth of alarge ring gear mount-- ed on the engine flywheel. A starting motor of moderate torque is generally more eflicient than one of extremely high torque, consequentlya high ratio between the number of .reduction by using two gear trains.

teeth in the pinion and the number in the ring gear is desired thereby producing a high torque and low speed of the flywheel ring gearv with a relatively low torque and high speed of thestarter pinion. As the size of the ring gear is limited by the diameter of the flywheel, the motor pinion must be made abnormally small which, when running at a high speed and meshing with a larger gear, produces excessive noise. Noise is also produced withthis type of drive when the pinion engages the gear. It is my object therefore to eliminate the .greater part of these noises by using only gears of relatively small ratios and getting the desired The gears are in mesh at all times, the starting gears being stationary however, after the engine is running.

Still a further object of my invention'is to provide an internal combustion engine having a' generator connected thereto which will be positively driven by the engine when the latter is running and located in such position so as to be accessible for inspection or repair at all times.

Still a further object of my invention is to provide a starting motor connected at all times thru a series of gears, with a ratchet wheel located in such a position that one or more pawls mounted on the crank shaft, will be free to engage with it.

Still a further object of my invention, is to provide a pawl support directly connected to the engine crank shaft, having a plurality of pawls fastened to the said pawl support so that when the engine is stopped one or more pawls will be forced by gravity to engage with said ratchet wheel thereby forming a driving connection between the ratchet wheel and the pawls and therefore a connection between the starting motor and the engine.

Still a further object of my invention is to provide a pawl support, directly convide a sto starting motor and the engine, also to profor each pawl so that when the pawl isin ts outward position it will be held against the said stop. In this connection it may be well to bring out that in conventional types of ratchet drives the ratchet is connected to the engine and the pawl to the driven member but this has the disadvantage that the pawl must be held from dropping on the rotating ratchet by some mechanical means as the noise produced by the pawl striking each ratchet tooth is excessive. It willbe noted that in my improved device no such objection isencountered as the pawls are held away from the'stationary,

ratchet by centrifugal force, due to their rotation with the crankshaft of the engine.

Still a further'object of my invention is to provide a combined starting and generating unit which will be disposed on the front cross member of the car frame and connected to the engine by an extension fastened to the crankshaft. of the engine so that the unit may be easily removed or the engine may be taken out of the car without disturbing the unit.

Still a further object of my invention is to provide means for cranking the engine by hand, when desired, thru the aforesaid extension to the engine crankshaft.

With these and other objects in view, my invention consists in the arrangement, combination, and construction of the various parts of my improved device, as described in the specifications, claimed in my claims and shown in the accompanying drawings, in

which:

Fig. 1 shows a top view in somewhat diagrammatic form, of an engine road wheel,

bumper, front spring and frame such as are normally used in connection with a motor vehicle and having my improved combined starter and generator unit mounted thereon.

Fig. 2 shows an enlarged detail top "view of my combined starter and generator unit, parts being broken away to better illustrate the construction. I

Fig. 3 shows a vertical central longitudinal sectional view thru the unit illustrated by Fig. 2.

Fig. 4 shows a vertical transverse sectional view taken on lined-4: of Fig. 3.

Referring to the accompanying drawings,

' I have used the reference numeral 10 to indicate generally the engine of an automobile so as to form a protection or the combined,

startergenefator unit to which I have given the numeral 17. This unit17 is fastened securely to frame 12 at the center of the front cross member and to theoutside thereof by means which will be hereinafter described.

Referring to Fig. 3 a shaft 20 with splines 21 on the outer end thereof is fastened to the front end of the engine crankshaft in any suitable manner and splines 21 are inserted in'corresponding splines in a con ling 22 and extend to about the middle of said coupling. The shaft 23 is formed with splines 24. at one end and ratchet teeth 25 at the other end. The splines 24 are inserted into correspoding splines in coupling: 22 to about midway in the coupling thereby making a driving connection between the ratchet teeth25 thru coupling 22 thrushaft 20 to the engine crankshaft. It can thus be seen that when the engine is running the shaft 23 is also rotating at crankshaft speed and that in case the en-f and also the front cover for housing 26. The.

inside of housing 26 when cover 29. is in place is of such size that the drive gears and ratchet wheel to be described later, maybe located therein. The housing 26 and cover 29: are provided with,-a plurality of aligned pairs of openings aroundtheir edges to re-' ceive screws (26A) for securing the cover 29 to the housing 26. Said housing 26 and cover are also 'provided'with three pairs of aligned openings 34 to receive the bolts 27. A boss 32 extends r'earwardly from the housing 26 and receives a bea-ring'33 which forms the forward bearing for the shaft 23. The frame member 11 is also provided with a plurality of openings aligned with openings 34 in housing 26 and one large opening 82 to form an opening into which the boss 32 may be inserted whereby bolts 27 are passed thru the "cover29", thehousing 26, and frame 11 and fastened on the insideof the frame, thereby holding the wholeunit securely to the front cross member of the said frame. The

housing 26 is also provided with-a removable screw plug (28) which may be taken out to drain the gear lubricant in case it is desired to disassemble the unit. The cover 29 is provided with a centrally located opening aligned with the opening in the boss 32 ofthe housing 26, of such size that it will form a support and mounting'for the forward hearing (33) for the shaft 23.

The generator 30 and thestarter 31 are of cylindrical cross section and mounted on the cover 29 in approximately the position shown in Fig. 2 and Fig. 3, their armature shafts being parallel tothe shaft 25 and also to the engine crankshaft and spaced so that the ratchets 25 on shaft 23 may lie between them.

The cover 29 is also provided with two openings located centrally with reference to the starter 31 and the generator 30 designed to form a support for their armature bearings which will later be described.

Thegenerator' 30 is of the conventional type havin a cylindrical shell 34 into which fits an end cover and bearing support 35. The field coils 36 are mounted on cores 37 which are fastened onto shell 34. An armature 38 is supported by the shaft 39 which is supported at the forward end by a bearing (not shown) in the end cover 35 and at the rear end by the bearing 40. A shoulder 41 on the shaft39 adjacent to the bearing 40 holds the said bearing in position on the shaft 39. A portion of the shaft 39 on the extreme rear end is threaded leaving a portion of the shaft between the shoulder 41 and the threaded portion of sufficient length to receive the bearing 40 and a drive gear 42 the latter being composed of a hub 43 in which is located an opening correspondlng to the reduced section of the shaft 39. A lock washer 44 and a nut 45 are assembled on the threaded portion of shaft 39 and bind the gear 42 and the inner race of bearing 40 on shaft 39, the gear 42 is provided with teeth 46 which are in constant mesh with a drivlng gear mounted on the shaft 25. v,

The cover 29 has a circular boss 47, pro ecting from its forward face of a diameter slight- 1 smaller than the inside of body 34 thereby fbrming a locating ring for the generator 30. A plurality ofmachine'screws 48, (illustrated in F ig, 4) extend thru suitable openings in cover 29 inside of the shell 34 and are threaded into theend cover 35, thereby holding the whole generating unit together and also fastening it securely onto the cover 29.

The starting motor 31 is similar in construet-ion to the generator 30, the size and shape being approximately the same. The shell 51 is of cylindrical form and has field :oils 52 mounted on the cores 53 which are suitably secured to body 51. An armature 54 is secured to the motor shaft 55 and the whole is rotatably mounted on the bearing 5am the cover 29 and on a suitable bearing in the end cover 57. The bearing 56 is a ring of antifriction metal pressed into the cover 29 before the starter 31 is in place. The cover 29 has a boss 58 similar to the boss 47 used to locate the starter 31 and hold the same in alignment with the unit. A plurality of machine screws 59 are inserted in the cover 29 thru suitable openings and extend thru the inside of the body 51 to the cover 57 in to which they are threaded thereby holding the starter parts in assembled relation and the starter onto the housing cover 29. 4 The shaft 55 extends rearwardl beyond the bearing 56 a distance sufficient or the gear teeth 60 which are cut in its rear end and form a pinion, to meshwith the idler gear 61. A trunnion 62 extends between bearing bosses, not shown in the drawings, but located in the housing 26 and the cover 29 in such position as to holdthe trunnion 62 parallel to the shaft 55. A dual reduction gear which I have designated generally as 63 has two sets of teeth thereon, the said teeth or gear member 61 being the gear which receives the rotating impulse from the starter 31 thru the pinion 60, and a smallergear member 64 which is rotated by gear 61 and imparts its rotation to the driving ratchets. The trunnion 62 forms the support for this dual gear upon which it is rotatably mounted and held from end motion by the bearing bosses on the housing 26 and the cover 29. a

As has been previously stated, the shaft 23 is provided with splines on its inner end which flange extending forwardly from flange 66 forms a gear 69 of sufficient diameter which meshes with the generator drive gear 42. In the outer edge of flange 66 a plurality of pawl pins 70 are mounted to form a support for the pawls 71.

The pins 70 are of circular cross section, and

\ have reduced ends whereby a shoulder is formed at each end of each pin. A ring 72 of the same outside diameter as the flange 66 is 'mounted on the free ends of the pins 70 to form a brace for said pins and a guide for the pawls 71, the starting ratchet being disposed between the ring 72 and the flange 66.

A plurality of stop pins 74 similar to pawl pins 7 Care mounted between flanges 66 and ring 72 in the same way, said pins 74 forming stops for the pawls 71 so that the latter may not move outwardly further than the outer edge of flange 66'. Four pawls are shown in mydrawings but it is my intention to cover the use of any number of pawls as it is only necessary to have one pawl to form a working unit, however, the greater the number of pawls the quieter the operation of the starter will be.

The outer surface of hub 67 of pawl holder 65 forms a bearing for the starting ratchet and gear which I will designate generally by the numeral 75. A sleeve 76 is rotatably mounted on hub 67, the outer periphery of said sleeve 76 being formed into a series of ratchet teeth 77 which are so formed that they and the pawls 71. A series of teeth 80 are out i in the outer periphery of the member 78 so as to form a gear which meshes with the pinion 64 of the dual reduction gear 63. From the foregoing it may be seen that a direct connection is obtained at all times from the engine crankshaft thru shaft 20, coupling 22, shaft 23, splines 24, pawl holder 65, and then to pawls 71. It will be understood in this connection that when the engine 10 is in operation the pawl holder 65 rotates continuously in the same direction as the engine crankshaft and that pawls 71 will also be rotated. The pawls 71 will thereby be forced outwardly by centrifugal for'cegthe outward movement of the pawl teeth being stopped by the pins 74, and thereby rotating freely and Without noise. The gear 69 is rotated continuously when the engine 19 is inoperation, being a part of the pawl holder 6'5 and therefore being driven continuously, and as the gear 69 is in constant mesh with the generator gear 42 Which is mounted on the generator armature shaft 39, the generator armature will also rotate continuously when the engine is running. From the foregoing it may be seen that the engine 10 is at all times connected to the pawl holder 65 which rotates directly with it and is also connected thru the gears 69 and 42 to the gener ator armature. Y

The starting motor 31 is normally station'- ary when the engine is in operation, that is its armature and shaft are not rotating, therefore pinion 60, the du l reduction gear 63, the gear 88and the starting ratchet wheel 75 are also stationary.

When the engine 10 is not running the 'pawls 71 will also be stationary, as has previously been described, and thepawl'which happensto be on'the upper side of the ratchet wheel 77 will drop down by gravity against ratchet 77 either on top of a tooth or in the which happens to be in contact with the In the practical operation of ratchet wheel 77 will impart this rotary motion to pins 7 0 and from there to the pawl holder 65 thru the shaft 23 to the coupling-22 and then to shaft 20 which is connected to the engine crankshaft thereby rotating the said'crankshaft.

my improved combined starter and generator unit, let it be assumed that the engine is idleand that the Various parts of the starting device are in their normal inoperative position. Upon a source of current (not shown) being applied to motor armature 54, the same together with its shaft begins to rotate; Since the dual gear I 63 forms a\connection bewteen the ratchet gear 80 and, the armature pinion 60 the said ratchet gear begins to rotate also, carrying with it ratchet wheel 77D One or vmore of the pawls 71 that are engaging the said-ratchet Wheel are engaged by the'teeth of the ratchet and tend to be carried along with them, this action applying a rotary motion to pins and also to pawl holder 65 in which the pins are located. As there-is a driving connection between pawl-holder 65 and the crankshaft of engine 10 thru splines 24, shaft 23, coupling 22 and shaft 20, a rotary motion is also applied to the said crankshaft. l/Vhen the engine starts on its own power the crankshaft accelerates and acquires a speed exceeding that imparted to it by the starting device thereby rotating the pawl holder and pawl at a similar speed.

The faster relative rotation of the pawls around the ratchet wheel disconnects the pawls from,said ratchet wheel and due tot-he rotation centrifugal force urges the pawl teeth 71 out of engagement with the ratchet wheel and against pins 74 and lets them rotate freely in this position. When the current to starting armature 54 is cut ofi, the armature comes to rest thereby holding the ratchet wheel 77 stationary.

As the gear 69 forms a part of the pawl holder 65 this gear will always rotate when the engine 10 is running. As the gear 69 is in constant mesh with the generator drive gear 46, the latter is rotated at a speed corresponding to the ratio between the gear 69 and the gear 46 and in turn rotatesthe generator armature 38 towhich it is connected ,thru the shaft 39. It therefore is evident that the generator armature 38 rotates in a concrank will impart a rotary motion to the crankshaft identical to that motion imparted by the starting motor 31. From this'it may be seen that if for any reason it is desired to crank the engine 10'by hand, the engine may be cranked by the use of a suitable hand "crank.

-Among the many advantages arising from the use of my device, it willbe noted that while under ordinary running conditions starting motor 31 is never. operated, yet

should for any reason the starting motor be set into rotation while the engineis rotating rapidly, there would beno connection whatfore out of connection with ratchet 77.

The gear reduction which I have embodied in my starter and generator will be noted 3 to be as follows: Starter pinion 60 has seven teeth meshing with gear GlWhlCll has twenty six teeth. Gear 61 is a unit with pinion 64- twenty to onewhich allows a starting motor of high speed and moderate torque to be used.

Gear 69 is formed with thirty eight teeth and gear 42 has thirty-three teeth giving an increase in the speed of the generator of about one to one and fourteen one hundredths compared to that of the engine crankshaft. Both of these ratios are considered good practice in automobile design, but I do not wish to limit myself to the exact ratios shown as any reasonable gear ratios may be used without departing from the spirit of my invention.

The assembly of my improved device is accomplished with comparatively few operations. The starter armature 54 and genera tor armature 38 are placed in their respective housings 31 and 30 and these housings are secured onto cover 29 with the machine screws 48 and 59, the bearings 40 and 56 having been previously assembled in cover 29. The gear 42 and the bearing 46 are secured on to the shaft 39 by the nut 45. The pins 70 and 74 are riveted in alternate holes in the holder and the pins are then inserted in the openings inpawls 71, the

backs of the pawl teeth resting against the pins 74. The ring 72 is now rivet-ed to the ends of pins 70 and 74 and the said pins are riveted in place forming a compact unit. The ratchet gear 75 is now assembled over the hub 67 with the ratchet teeth 77 adjacent to flange 66. The bearing 33-A is slipped over the splined end of shaft 23 adjacent to a shoulder 81 provided on said shaft and the ratchet unit is then slipped on the shaft 23 with gear 69 encircling bearing 33A. The bearing 33 is then mounted directly on splines 24, the remaining section of splines 24 being taken up by coupling 22. This whole unit is now mounted in the housing 26, the bearing 33 being inserted in a central hole in boss 32 provided for it in said housing. The trunnion 62 is now inserted in the trunnion boss in housing 26 and the dual gear 63 is mounted upon said trunnion. The cover 29 with the motor and the generator attached is now placed on the housing 26 so that bearing 33A is inserted in the central opening in said cover. The screws 27-A are extended thru the cover 29 and screwed into the housing 26. The shaft 20 is attached to the front end of the engine crankshaft which is aligned with the opening 82 in the front cross member of the frame 11 designed to receive the boss 68 of the housing 26. The coupling 22 of the assembled unit is now placed thru this opening from the forward end and the whole unit is locked in place by machine bolts 27.

Some changes may be made in the arrangement and construction of the various parts of my improved device without departing from the spirit of my invention and it is my intention to cover by the following claims such changes as may be reasonably included within the scope thereof.

I claim as my invention:

1. In a combined generator and starter unit, a housing, a shaft extended therethrough intermediate of the ends thereof, a combined bearing sleeve and pawl holder and generator gear member mounted on said shaft and adapted to be held from rotation relative thereto, a combined ratchet wheel and. drive gear journalled on said bearing sleeve in position where the ratchet wheel may be engaged by said pawls, a generator mounted on said housing at one side of said shaft, a starter mounted on said housing on the other side of said shaft, and means for operatively connecting the generator and starter respectiyely with the generator gear and the drive gear.

2. In a combined starter and generator unit, a housing, a shaft extended through said housing and adapted to be connected at one end with the crankshaft of an engine and at the other end with a hand crank for an engine, a combined pawl holder and bearing sleeve and generator gear member fixed to said shaft, a combined ratchet wheel and drive gear journaled on said bearing portion in position where the ratchet wheel may be engaged by pawls mounted on the pawl holder, a generator mounted on said housing at one side of said shaft, a gear adapted to operatively connect said generator with the generator gear, a starting motor mounted on said housing on the other side of said shaft, and a reduction gearing between said starting motor and the drive gear, the parts being so arranged that the pawl mechanism will engage the pawl wheel when the starting motor is operated to thereby drive said shaft, and so that the pawl mechanism will be rendered inoperative by centrifugal force when the shaft is being rotated by means other than the starting motor.

3. In a combination starter and generator I mounted on the pawl holder, and a generator driving gear adapted to mesh with the first described gear and mounted on said housing.

Signed at the city of Detroit, county of Wayne, State of Michigan, this 14th day of August, 1926.

HENRY FORD.

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