US2332864A

US2332864A - Starter gearing for internal combustion engines

Info

Publication number: US2332864A
Application number: US381688A
Authority: US
Inventors: Thomas B Martin
Original assignee: Bendix Aviation Corp
Current assignee: Bendix Aviation Corp
Priority date: 1941-03-04
Filing date: 1941-03-04
Publication date: 1943-10-26
Anticipated expiration: 1960-10-26

Description

Oct. 26, 1943. T. B. MARTIN 2,

STARTER GEARING FOR INTERNAL COMBUSTION ENGINES I Filed March 4, 1941 2 Sheets-Sheet 1 7 1 jg 15 68 z 19 17 INVENTOR.

J/winasfl.

T. B. MARTIN Oct. 26, 1943.

I STARTER GEARING FOR INTERNAL COMBUSTION ENGINES Filed March 4, 1941 2 Sheets-Sheet 2 INVENTOR. homasfi. JTLaW/tin/ ATTORNEY.

Patented Oct. 26, 1943 UNITED STAT I 2,332,864; Fl CE STARTER GEARING FOR INTERNAL -COMBUSTION ENGINES Thomas B. Martin, Dayton,0hio, assignor to Benclix Aviation Corporation, South Bend, Ind., a

corporation of Delaware Application March 4, 1941, Serial No. 381,688

13 Claims.

The present invention relates to starter gearing for internal combustion engines and more particularly to that type in which a motordriven pinion is shifted manually or by other extraneous means into and out of engagement with a member of an engine to be started.

In installations of this character it is desirable to connect the pinion to the starting motor through some form of overrunning clutch device in order to permit the engine member to accelerate when the engine becomes self-operative with.- out accelerating the armature of the starting motor to a dangerous or harmful speed of rotation. Considerable difficulty has been encountered in constructing an overrunnin clutch for this purpose which will on the one hand transmit the cranking torque at all times without slippage, and on the other hand will release and overrun without sticking.

It is an object of the present invention to provide a novel starter gear shift which is efficient and reliable in operation and simple and economical in construction.

It is another object to provide such a device which is arranged to couple the pinion to its drive shaft positively and with small lost motion .upon the actuation of said shaft. i

It is a further object to provide such a device in which the coupling action may be cushioned if deemed desirable without rendering the action anyless positive and certain.

It is another object to provide such a device in which the coupling is arranged to overrun freely when the engine becomes self-operative without causing undue acceleration of the drive shaft.

It is another object toprovide such a device in which localized stresses are avoided, and the torque is transmitted by pressures on comparatively large surfaces which are arranged at a considerable angle to the direction of the force transmitted.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawings in Which:

Fig. 1 is a side elevation partly in section of a preferred embodiment of the invention;

Fig. 2 is a section taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a section taken substantially on the line 3-3 of Fig. 1;

Fig. 4 is a view similar to Fig. 1 showing a second embodiment of the invention;

Fig. 5 is a section taken substantially on the line 5-5 of Fig. 4;

Fig. 6 is a view similar to Fig. 1 of a third embodiment of the invention;

Fig. 7 is a section taken substantially on the line .ll of Fig. 6;

Fig. 8 is a view similar to Fig. 6 showing the parts in operative or driving position;

Fig. 9 is a view similar to Fig. 4 showing the control nut fixedly attached to the drive sleeve instead of being frictionally clutched thereto, and showing the pinion bushing formed to act as a detent for the screw shaft;

Fig. 10 is a section taken substantially on the line Ill-I0 of Fig. 9; and

Fig. 11 is a detail in side elevation of the pinion with its clutch member and frictional mounting for the screw shaft illustrated in Fig. 9,

In Fig. l of the drawings there is illustrated a power shaft I having a drive sleeve 2 splined thereon. A pinion member 3 is slidably journalled on the power shaft and connected for longitudie nal movement with the drive sleeve by means of a barrel member 4 fixedly attached to the pinion as indicated at 5 and swiveled to the end of the sleeve 2 by means of a radial flange 6 on the end of the sleeve which is confined between split thrust rings I and 8 mounted in the interior of the barrel.

An overrunning torque transmitting connection between the sleeve and pinion is provided comprising a screw shaft 9 slidably journalled on the power shaft inside the barrel 4 and having clutch teeth II on one end thereof. A, toothed clutch member I2 is rigidly mounted in the end of the sleeve 2 in any suitable manner as by Welding or brazing in position to be engaged by the clutch teeth I I of the screw shaft 9 when the screw shaft moves tothe right in Fig. 1. A nut I3 is threaded on the screw shaft 9 within the barrel 4 and is maintained in frictional engagement with a washer I4 at the inner end of the barrel by spring means such as a dished spring washer i5 engaging an annular projection IS on the nut and seated against the split thrust ring 1 in the barrel.

Means for shifting the sleeve 2 with the pinion and barrel longitudinally on the power shaft I to move the pinion into and out of engage ment with an engine member, is provided in the formof a shift collar ll slidably mounted on the periphery of the sleeve 2 and yieldably held against a split thrust ring Iii by a'compression spring I9 bearing against the flange 8 of the sleeve.

Means for frictionally connecting the screw shaft 9 to the power shaft I is provided in the.

form of a spring clutch ring'fii (Fig. 3) anchored to the screw shaft at one end as by means of an outturned terminal portion 122 located in a radial bore 23 in the screw shaft, and wound around the power shaft inoa direction to cause the clutch ring to grip the shaft'when the shaft rotates in a forward direction as indicated by the arrow in Fig. 3. p

In the operation of this embodiment of the invention, after the pinion 3 has been moved into engagement with an engine gear, rotation of the power shaft I by a starting motor, not illustrated, will cause rotation of the. sleeve Z by virtue of tionary by its frictional connection through the washer l4 and the spring washer i5 with the pinion barrel 4, the screw shaft 9' will be caused to move to the right in Fig. 1 until the clutch H, 12 is closed. Thereafter, the screw shaft is positively rotated through said clutch from the power shaft I, and the nut I3 is forced against the washer l4 by the screw jack action between the screw shaft and nut whereby the pinion 3 is constrained to turn with the sleeve 2 and consequently with the powershaft I. When the engine startsthe overrunning of the pinion causes the screw shaft to be threaded to the left in Fig. 1, causing it to be declutched from the sleeve and power shaft whereby the pinion, barrel, nut and screw shaft overrun freely until the assembly is returned to idle position by the operator. In the embodiment of the invention illustrated in Figs. 4 and 5 a powershaft 3! has splined thereon a sleeve 32, and a pinion 33 is slidably journalled on a bushing 34 freely mounted on the power shaft and extending into the end of the sleeve 32.

Sleeve 32 is provided with an enlarged bell 35 fixed to the sleeve in any suitable way as by welding or brazingas indicated at 36 and having a swiveled connection with the pinion 33 as by means of a flange 3'l fi xed in any suitable way to the pinion and confined in the end of the bell bymeans of a Washer 38 located by a split lock ring 39. I J t The inner end of the pinion 33 is formed as a dental clutch 4!, and a screw shaft #32 is slidably journalled on the bushingi l and provided with clutch teeth 43 adapted to cooperate with the clutch 4|. Means for yieldingly urging the screw shaft in a direction to close the clutch is provided in the form of a return spring bearing against the screw shaft at one end and at its other end against a Washer 45 retained by a flange 46,0n theend of the bushing 3 I A nut 41 is threaded on the screw'shaa 42 and is provided with afco nic'al periphery 48 bearing against an inner conical surface 49 of the bell 35 so as to form a friction clutch, connection therewith. Means for yieldingly holding these surfaces "in contact is provided in the form of a spring washer 5! bearing against an annular projection 52 on the nut and seated against a split thrust ring 53 in the bell 35. l

Means for shifting the sleeve 32 along the power shaft l in'order to cause the pinion 33 to engage an engine member, is provided in the form of a collar 54 slidably mounted on the sleeve '32 and maintained thereon by a split thrust ring 55 against the pressure or a spring 58 bearing against the end of the bell 35.

the shift collar 54 is actuated by'any When conventional type of shift fork to move the pinion into operative. position, power shaft 3i will be rotated by a starting motor, which rotation is thereupon transmitted through the splines to the sleeve "32 and bell 35, thus causing rotation of [the mm 4'! through its frictional connection with the bell 35. The screw jack action between the nut and screw shaft thereupon causes the screw shaft to move to the left, closing

clutch

41,43, after which the nut i'l is forced againstthe interior of the bell 35 so as to form a driving connecaonnom the bell "through the nut and screw the pinion. When the engine starts, the

overrunnin'g'of'the pini on'causes'the screw shaft thereto in any suitable way as indicated at 65.

A bell 66 is suitably fixed on the end of the sleeve 6'2 surrounding the nut es and ha a ring at of elastically deformable material mounted therein. Ring 6'5 is held under initial compression by means of a thimble 6S surrounding the nut 64 and seated against a shoulder 65 in hell E6, and a thrust ring H bearing against a split lock ring 12 in the open end of the bell. Nut ii is provided with a radial flange E3 in the bell 65 adjacent the thimble 58 whereby the nut and consequently the pinion are swiveled to the bell and sleeve 62. V

A screw shaft '54 is slidably jour'nalled on the power shaft and is provided at one end with a clutch formation is adapted to engage a clutch member 16 fixed in the end of sleeve 52. Selftightening means frictionally connecting the screw shaft to th power shaft fiiis provided in the form of a clutch ring 'i'! (Fig. 7) anchored to the screw shaft by an outturned end '58 lodged in a radial bore 'EQ of. the screw shaft and wound around the power shaft in a direction to frictionally grip it when it turns in a forward direction as indicated by the arrow.

A shifting thinible ti is'slidably mounted on the sleeve 62, retained thereon by a split lock ring $2 and having a yieldin thrust connection with the sleeve through. a compression spring 83.

When the shift collar Si is actuated by any conventional form of shifting fork to rnove the pinion into engagement with an engine gea such as indicated at 84 in Fig. 8, rotation of the power shaft Si is transmitted to the sleeve 62 through its splined connection therewith and is transmitted to the screw shaft M by the friction clutch ring Tl. Since the nut 5c is held stationary by its connection with the pinion as, the screw shaft T4 is caused to move to the right, closing clutch 15, T6. Thereafter the nut as is caused to move to the left, eompressingthe lastic ring 6'! until sufficient torque is built up to cause rotation to be transmitted to the pinion and engine gear.

When the engine starts, the overrunning of the pi'nio'nfifi causes the screw shaft 14 todeclutch, whereupon the pinion, nut and screw shaft overrun until the pinion is moved back to idle position by the shifting means.

The structure illustrated in Figs. 9, 10 and 11 i similar to that shown in Figs. 4 5 and the parts are similarly numbered, but in this case the nut and bell are formed integrally and designated by the numeral 56, the pinion flange is formed as the clutch member and is numbered All, and the screw shaftdZ is 'frictionally connected to the pinion by cutting a spiral'groove 3D in the projecting end of the pinion bushing 35a whereby the bushing acts as a self-expanding clutch within the screw shaft. ,"The operation of this structure is substantially the same as that illustrated in Figs. 4 and 5 except that the connection to the pinion is more positive, and the traversal of the screw shaft isffacilitated by reason of the fact that the spir lly cut end of the bushing 36a. is longitudinally compressible so that while the bushing retards rotation of'the screw shaft, it does not materially impedefits longitudinal movement;

have been shown and described in detail, it will be understood that other embodiments are possible and various changes may be made in the construction and arrangement of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is:

1. In a starter gear, a power shaft, a sleeve member slidably but non-rotatably mounted thereon, a pinion member slidably journalled on the shaft and connected for longitudinal movement with the sleeve, and an overrunning torque transmitting connection between the sleeve member and pinion member including a threaded ring slidably and rotatably mounted on the power shaft having clutch teeth on one end, a nut threaded thereon having a torque transmitting connection with one of said members; and clutch teeth rigid with the other said member and adapted to cooperate with the clutch teeth of the ring and form a torque transmitting connection therebetween.

2. In a starter gear, a power shaft, a sleeve member slidably but non-rotatably mounted thereon, a pinion member slidably journalled on the shaft and connected for longitudinal movement with the sleeve, and an overrunning torque transmitting connection between the sleeve meniber and pinion member including a threaded ring slidably and rotatably mounted on the power shaft independent from said sleeve having clutch teeth on one end, a nut threaded thereon having a torque transmittin and thrust connection with one of said members, and a toothed clutch member rigid with the other said member and adapted to cooperate with the clutch teeth of the ring and form a torque transmitting connection therebetween when said teeth are forced into engagement by the screw jack action of the ring and nut. I v 3. In a starter gear, a power shaft, a sleeve member slidably but non-rotatably mounted thereon, a pinion member slidably journalled on the shaft and connected for longitudinal movement with the sleeve, and an overrunning torque transmitting connection between the sleeve memberand pinion member including a threaded ring slidably and rotatably mounted on the power shaft, a nut threaded thereon having, a torque transmitting connection with one of said members, a frictional connection between the ring and the other of said members, and a positive torque transmitting connection to the ring established by the screw jack action of thering and nut.

4. Starter gearing as set forth in claim 1 in which means are provided for cushioning the establishment of the driving connection between the sleeve and pinion.

5. Starter gearing as set forth in claim 1 incorporating a self-tightening frictional connection between the sleeve and nut.

6. Starter gearing as set forth in claim 1 incorporating a block of elastically deformable material interposed between the sleeve and nut and arranged to be compressed by the action of the threaded ring and nut to yieldably connect the sleeve to the nut for rotation in unison,

7. In an engine starter gear, a power shaft, a pinion slidably journalled thereon, and means for connectin the pinion to rotate with the shaft including a sleeve non-rotatably mounted on the connection between the screw shaft and pinion established by screw jack action between the ring and nut.

8. In an engine starter, a power shaft, a pinion slidably journalled thereon, a sleeve splined to the shaft and having a swiveled connection with the pinion, means for, shifting the sleeve along the shaft, a threaded ring .rotatably and slidably mounted on the power shaft having a clutch member at one end, a nut threaded on the ring, and means including a member cooperating with the clutch member on the ring to transmit rotation throughthe ring and nut from the sleeve to the pinion.

9. In an engine starter, a power shaft, a pinion slidably journ'alled thereon, sleeve splined to the shaft and having a swiveled connection with the pinion, means for shifting the sleeve along the shaft, a threaded ring rotatably and slidably mounted on the power shaft,a nut threaded on the ring having a torque-transmitting connection with the pinion, and means including a clutch closed by the screw jack action of the ring and nut for transmitting rotation from the sleeve to the pinion.

10. In an engine starter, a power shaft, a pinion slidably journalled thereon, a sleeve splined to the shaft and having a swiveled connection with the pinion, means for shifting the sleeve along the shaft, a threaded ring rotat'ably and slidably mounted on the power shaft having a clutch member formed on one end, a nut threaded on the ring having a torque transmitting connection with the pinion, and a clutch member rigid with the sleeve cooperating with the clutch member on the ring to transmit torque from the sleeve through the ring and nut to the pinion.

11. In an engine starter, a power shaft, a pinion slidably journalled thereon, a sleeve splined to the shaft and having a swiveled connection with the pinion, means for shifting the sleeve along the shaft, a threaded ring rotatably and slidably mounted on the power shaft having a clutch member formed on one end, a nut threaded on the ring having a torque transmitting connection with the sleeve, and a clutch member rigidwith the shaft, a nut fixed to the sleeve and swiveled to pinion cooperating with the clutch member on the ring under the screw jack action of the ring and nut to transmit torque from the sleeve through the ring and nut to the pinion.

12. In engine starter, a power shaft, a threaded ring slidably journalled on the power shaft and frictionally connected to rotate therewith, a sleeve splined to the power shaft, a pinion slidably journalled on the power shaft and swiveled to the sleeve, a barrel fixed to the pinion, a nut threaded on the ring within the barrel and frictionally connected to the barrel, and clutch means closed by the screw jack action of the ring and nut for transmitting torque through the ring .threaded on the ring, means for moving the sleeve, nut and pinion along the shaft in unison to mesh the pinion with an engine member, and means including a clutch closed by longitudinal movement of the ring in the nut to transmit rotation from the sleeve to the pinion.

THOMAS B. MARTIN.