US2885894A

US2885894A - Engine starter gearing

Info

Publication number: US2885894A
Application number: US573377A
Authority: US
Inventors: Charles A Mendenhall
Original assignee: Bendix Aviation Corp
Current assignee: Bendix Aviation Corp
Priority date: 1956-03-23
Filing date: 1956-03-23
Publication date: 1959-05-12
Anticipated expiration: 1976-05-12

Description

y 1959 c. A. MENDENHALL 2,335,894

ENGINE STARTER GEARING Filed March 23, 1956 v IN VEN TOR. cad/168mm? WITNESS 2m. 92%; V iaxfi TOHNE Y ted. StatcsP .0"

ENGINE STARTER GEARIN G Charles A. Mendenhall, Horseheads, N.Y., assignor to Bendix Aviation Corporation, a corporation of Delaware Application March 23, 1956, Serial N 0. 573,377

4 Claims. (Cl. 74-6) The present invention relates to engine starter gearing and more particularly to that type in which a pinion is shifted manually or electro-magnetically into and out of mesh with a gear on the engine to be started.

The presently prevailing demand for high gear ratios from the starting motor to the engine crank shaft has forced the reduction in size of the driving pinions to the point where any future reduction necessitates the use of a solid pinion. Satisfactory maintenance of alignment and spacing of such a pinion, however, presents a problem, especially in view of prevailing overall space limitations.

It is an object of the present invention to provide novel starter gearing of the above type incorporating a solid pinion with self-contained supporting means for the pinion.

It is another object to provide such a device having a bearing on the motor shaft for rotatably supporting the pinion and additional clamping and supporting means for assisting in maintaining alignment during the cranking operation.

It is another object to provide such a device incorporating an overrunning clutch located closely adjacent the pinion to reduce the mass of the overrunning parts and therefore secure improved performance.

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

Fig. 1 is a side elevation partly broken away and in section of a preferred embodiment of the invention with the parts shown in idle position; and

Fig. 2 is a similar view showing the parts in cranking position.

In Fig. l of the drawing there is illustrated a power shaft 1 which may be the extended armature shaft of a starting motor not illustrated. The shaft 1 is formed with a splined portion as indicated at 2, and a sleeve 3 is slidably but non-rotatably mounted on said splined portion.

A bearing member 4 is rigidly mounted on the end of the motor shaft 1 as by means of a cross pin 5, and a cup member 6 having a pinion 7 rigidly mounted thereon is slidably journalled on the bearing 4 for movement of the pinion into and out of mesh with a gear 8 of the engine to be started.

The sleeve 3 is provided with a terminal radial flange 9 having inclined coupling teeth 11 adapted to cooperate with similar teeth 12 on a transmission member 13 having a slidable bearing on the cup member 6. The transmission member is also provided with over-running clutch teeth 14 adapted to engage similar teeth 15 on a flange ring 16 which is rigidly mounted on the exterior of the cup member 6 in any suitable manner as by brazing as indicated at 17.

A barrel member 18 surrounds both said flanges and the transmission member 13, and bears slidably on the flange 9 of sleeve 3 and on said transmission member.

2,885,894 Patented May 12,-?'9

2 1 A thrust bearing ring 19 for the flange ring :16 isloosely mounted in one end of the barrel member and is retained in the barrel by a lock ring 21. A compression spring in the form of a plurality of elastic disc members 22 is located within the barrel adjacent its opposite end and is compressed against the flange 9 of the sleeve by a a thrust disc 23 retained in the barrel by crimping in the end of the barrel as indicated at 24. Expansion of the spring 22 is limited by a lock ring 25 seated in the sleeve 3 in position to engage the thrust disc 23.

Means for shifting the sleeve 3 to move the pinion 7 and its associated parts into and out of meshing position is provided comprising a shifting fork 26 which may be manually or electro-magnetically operated, and is provided with trunnions 27 operating in a shift collar 28 which is retained on the end of the sleeve 33 by a lock ring 29. A spring 31 is arranged to yieldably transmit the movement of the shift collar 28 to the thrust disc 23.

In operation, starting with the parts as illustrated in Fig. l, movement of the shift fork 26 to the right is transmitted through the shift collar 28 and spring 31 to the sleeve 3 by means of thrust disc 23 and spring 22. This movement is transmitted through the transmission member 13 to the flange ring 16, cup 6 and pinion 7 to move the pinion into meshed position as shown in Fig. 2. When the motor is energized, the torque transmitted through the

coupling elements

11, 12 forces the transmission member 13 to the right, thereby clamping the flange ring 16 tightly in the barrel whereby the cup 6 is held rigidly in alignment with its bearing 4 on the motor shaft. The reaction of this clamping pressure is taken by the thrust spring 22 which may permit the

coupling elements

11, 12 to ride over each other and thereby reduce the initial shock.

When the engine starts, the overruning action permits the transmission member 13 to move back toward flange 9 of sleeve 3, thus permitting the overrunning

clutch teeth

14, 15 to disengage and allow the pinion to overrun until such time as the pinion is drawn back out of mesh by release of the shifting fork 26.

Although but one embodiment of the invention has been shown and described in detail it will be understood that changes may be made in the design and arrangement of the parts without departing from the spirit of the invention.

I claim:

1. In engine starter gearing a motor shaft, a sleeve splined thereon, a bearing member fixed on the end of the shaft, means for traversing the sleeve on the shaft toward and from said bearing member, a cup member slidably journalled on the bearing member, a pinion rigidly mounted on the end of the cup member beyond the end of the shaft and movable thereby into and out of mesh with a gear of the engine to be started, a radially extending flange member rigidly mounted on the cup member adjacent the pinion, and means responsive to rotation of the sleeve for clamping the flange and cup member coaxially to the sleeve.

2. Starter gearing as set forth in claim 1 in which the splined sleeve is formed with a terminal flange, and the means for clamping the flange and cupmember to the sleeve includes a barrel member slidably mounted on the sleeve flange and extending over the cup flange, means in the barrel limiting separation of the two flanges, and a transmission member intermediate said flanges having wedging engagement therewith.

3. Starter gearing as set forth in claim 2 in which the flange on the splined sleeve is formed with inclined torquetransmitting teeth cooperating with similar teeth formed on said intermediate transmission member.

means for clamping the flange and cup member to the sleeve includes a ring mounted in the barrel having a radial surface forming a ihrust bearing for the cupmounted-flange. l

References Citedln the file of this patent UNITED STATES PATENTS