US2187545A

US2187545A - Engine starting mechanism

Info

Publication number: US2187545A
Application number: US250655A
Authority: US
Inventors: Raymond P Lansing
Original assignee: Bendix Aviation Corp
Current assignee: Bendix Aviation Corp
Priority date: 1939-01-12
Filing date: 1939-01-12
Publication date: 1940-01-16
Anticipated expiration: 1957-01-16

Description

Jan; 1 6, 1940. R. P. LANSING 2, ENGINE STARTING MECHANISM Filed Jan. 12, 19:59

25 INVENTORQ Patented Jan. 16,

UNITED STATES.

PATENT OFFICE ENGINE STARTING MECHANISM Raymond P. "Lansing, Montclair, N. 5., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application January 12, 1939, Serial No. 250,655 7 9 Claims.

This invention relates to internal combustion engines, and particularly to the starting thereof. Internal combustion engines are commonly started by means of devices having rotatable eleb ments, one of which (referred to as an engine engaging member) is movable to engage a rotatable extension of the engine crankshaft, or crankshaft connected part, to impart initial rotary movement thereto, in synchronism with the delivery of fuel and ignition current to the engine cylinders. In some installations the rotatable engine-engaging member is electrically driven as in my Patent No. 1,962,397, granted June 12, 1934, while in others the rotative eiiort is first stored 15 in a spring (as by hand-winding thereof) and then delivered upon release of a latch or-eq'uivalent means for holding the spring fully wound.

My Patent No. 1,936,554 exemplifies this class of starters.

U Limitations upon the strength of the ordinary in stress by power operation, there would still be the problem of holding thespring in stress and I releasing such holding means ,at the moment when cranking of the engine became desirable.

With a high capacity spring it would bevery diiiicult, as well as hazardous, to operate such holding means. whether to hold the spring, to release it, or

0. both;

In the present invention this problem is solved by combining the spring stressing means, the

spring holding means; and the spring releasing means in a single instrumentality; and it is accordingly an object of the present invention to provide a spring starter wherein such a single instrumentality acts as the spring stressing means, the spring holding means, and the spring a releasing means.

A second object of the invention is to provide, in such a spring starter, a single instrinnentality involving a spring actuating cam and cam follower constructed and related, to each other and to the spring. in such manner as to facilitate storage of energy in the spring and the subsequent release thereof.

A third object of the invention is to provide, in

such a spring starter, a single instrumentality involving elements constructed and related, to each 5 other and to the spring, in such manner as to produce spring stressing and spring release as consecutive steps in a single, uninterrupted operation.

Aefourth object of the invention is to provide, 10 in such a spring starter, a single instrumentality involving spring stressing, holding and releasing elements actuated by a common prime mover related thereto and controlled thereby in such manner as to produce de-energization of the 1 prime mover drive automatically, and in timed relation to the delivery to the engine-engaging member of the engine starting energy.

A fifth object of the invention is to provide, in such a spring starter, transmission mechanism "go between the spring and engine-engaging member constructed and related thereto in such manner as to cause the engine-engaging member to move into engine-engaging position in response to release oi the spring, and out of engine-engaging as position after full expansion of the spring, and prior to de-energization of the electric motor or other prime mover.

These and other objects of the invention will become apparent from inspection of the follow- :0

ing specification when read with reference to the accompanyingdrawing wherein is illustrated the preferred embodiment of the invention; It is to be expressly understood, however, that the drawing is for the purpose of illustration only, and -gg is not designed as a deiinition of the limits of the invention. reference being had to the appended claims for this purpose.

In the drawing:

Pig. 1 is a 'longitudinal sectional view of a device embodying the invention; a

Fig. 2 is a diagrammatic view of the prime. mover in its relationship to associated parts; and

Fig. 31s a view of the preferred form of control cam. 45

In the drawing reference character I designates a prime mover in the form of an electric motor, and reference character I designates an engine-engaging. member movable into engagement with engine memberl and adapted to trans- '00 mit starting torque thereto in response to expansion of the spring I. Interposed between spring 8 and the screw-threadedrearward extension I of member ,is athrust and motion translating element ll threaded is ll coacting with the screw 9 to first move the latter forward and then produce rotation thereof in response to release of the energy previously stored in spring 8 by the means now to. be described.

The means for storing energy inspring 8, and then releasing said energy to start the engine, includes a pair of identical cam elements l2, l3 and a corresponding pair of cam followers I4, 15, the latter being in the form of rollers mounted on a common cross-head l6 whose intermediate portion receives one end ll of a connecting rod 18 whose opposite end is threaded to receive a nut l9 adjustably holding said rod I8 and the motion translating element Ill in assembled, working relationship. The cams l2, 83 are integral with a driveshaft 2i adapted to be rotated either by a hand-crank 22 or by the previously described electric motor 5; the connections therebetween including, as shown, a worm 2 on the outer end of the motor shaft, a worm wheel 25 driven by the worm at reduced speed, and a uni-directional clutch 26 permitting rotation of the shaft 2| by hand-crank 22 without opposition from the worm and gear 24%, 25, whenever hand operation is desired.

The cams l2, iii are shaped and mounted in such manner as to facilitate a gradual storage of energy in the spring 3 and a far more rapid delivery of the energy back to the motion translating element l0, also to permit automatic release of the stored energy prior to interruption of the rotation of the cams. To assure uninterrupted flow of current to the motor 5 prior to such release of the energy, and also prior to completion of a predetermined arc of rotation of the cams, sufficient to return the engine-engaging member 6 to the disengaged position shown in the drawing, I provide automatic circuit-breaking means in the form of a ring 3| rotatable with worm wheel 25 and having a projection 32 adapted to separate switch element 33 from switch element 34, with which it is normally engaged, when the cams reach the position in which radial line o:r: (Fig. 3) intercepts the center of the cam follower, which will then be substantially in the position shown; at 159:. In this I51: position the spring 8 will be slightly recompressed by virtue of the return movement of the cam followers, to the extent indicated in Fig. 3.

' The motor is initially energized by closure of hand-switch 31, said switch 31 being in the motor circuit, as is also the

switch

33, 34; it being understood that the operator will hold said handswitch 31 in closed position until the motor has been sufficiently energized to carry the controller 32 away from switch element 33, whereupon a circuit from source 40 is completed independently of the switch 31, so that the switch 31 can then be re-opened without causing stoppage of the cycle of operation. The continued rotation of the motor swings cams 36 in a clockwise direction and thus causes'retraction of the cam followers and further re-compression of spring 8. When this re-compression of spring 8 has been completed the outer points 36 of the cams willhave reached a position wherein further rotation frees the rollers l4, l5 from contact therewith, whereupon spring 8 expands and delivers the stored energy to the engine, the rollers l4, l5 being carried along with rod l-8 to assume positions, with respect to the cams, 'c'o'rresponding to that indicated by the full-time showing of roller IS in Fig. 3 From this point the roller is returned to the I51: position prior to deenergization of the motor, as above pointed out.

When the freeing of the rollers l4, 15 occurs, the resulting expansion of the spring 8 causes, first, a longitudinal movement of the engine-engaging member 6, said movement being due to the combined effect of the internally formed threadsand the externally formed splines on the motion translating thrust element I0the said splines being in engagement with corresponding splines on the inner cylindrical surface of fixed element 20, against the outer end of which the flange 33 of engine-engaging member 6 normally abuts. As the spring continues to expand--the engagement of the members 6 and I being completed by the firststage of such expansion-element iii moves further forward along the splines of fixed element 20, thereby causing continued rotary (cranking) movement of the now engaged parts 6 and 1, until all stored energy has been delivered thereto.

What I claim is:

-1. The combination with an engine-engaging member, a helically wound spring, and a driving connection therebetween, of means for compressing said spring, said means including a rotatable cam operating upon said spring in such manner that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows immediately upon completion of the compression thereof, and prior to cessation of rotation of the cam, and means for maintaining said cam in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said last-named means including an electric motor, a source of current, and a circuit that remains closed until said cam reaches a predetermined position in its cycle of rotation.

2. The combination with an engine-engaging member, a spring, and a driving connection therebetween, of means for compressing said spring, said means including a rotatable controller operating upon said spring in such manner that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows immediatelyupon completion of the compression thereof, and prior to cessation of rotation of the controller, and means for maintaining said controller in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said last-named means includ ing an electric motor, a source of current, and a circuit that remains closed until said controller reaches a predetermined position in its cycle of rotation.

3. The combination with an engine-engaging member, a helically wound spring, and a driving connection therebetween for producing axial (engine-engaging) and then rotary movement of said engine-engaging member, of means for compressing said spring, said means including a rotatable cam operating upon said spring .in such.

manner that the expansion of the spring, for

delivery of starting energy to the engineengag- ,ing member, follows immediately upon completion of the compression thereof, and prior to cessation of rotation of the cam, and means for maintaining said cam in rotation until the spring ha's'been fully compressed, released for expansion, and partially compressed again, said last-named means including an electric motor, a source of current, and a circuit that remains closed until said cam reaches a predetermined position in its cycle of rotation.

4. The combination with an engine-engaging member, a spring, and a driving connection therebetween for producing axial (engine-engaging) and then rotary movement of said engine-engaging member, of means for compressing said spring, said means including a rotatable controller operating upon said spring in such manner that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows immediately upon completion of the compression thereof, and prior to cessation of rotation of the controller, and means for maintaining said controller in rotation until the spring has been fully compressed, released for expansion, and partially compressed again.

5. The combination with an engine-engaging member, a spring, and a driving connection therebetween for producing axial (engine-engaging) and then rotary movement of said engineengaging member, of means for compressing said spring, said means including a rotatable controller operating upon said spring in such mannet that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows immediately upon completion of the compression thereof, and prior to cessation of rotation of the controller, and means for maintaining said controller in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said lastnamed means including an electric motor, a source of current, and a circuit that remains closed until said controllenreaches a predetermined position in its cycle of rotation.

6. The combination with an engine-engaging member, a helically wound spring, and a driving connection therebetween, 01' means for compressing said spring, said means including a rotatable cam operating upon said spring in such manner that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows-immediately upon completion oi the compression thereof, and prior to cessation of rotation of the cam, means for maintaining said cam in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said. last-named means including an electric motor, a source of current, a circuit that remains closed until said cam reaches a predetermined position in its cycle of rotation, manual means tor rotating said cam, and a oneway driving connection between said motor and cam, including one race that remains stationary whenever said manual means is operated.

"I. The combination with an engine-engaging manber, a springf and a driving connection 'therebetween, of means for compressing said spring, said means including a rotatable controller operating upon said spring in such manner that the expansion-oi the spring, for delivery or starting energy to the engine-engaging member,

follows immediately upon completion oi the compression thereof, and prior to cessation of rotation of the controller, means for maintaining said controller in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said last-named means including an electric motor, a source of current, a circuit that remains closed until said controller reaches a predetermined position in its cycle of rotation, manual means for rotating said controller, anda one-way driving connection between said motor and controller, including one race that remains stationary whenever said manual means is operated.

8. The combination with an engine-engaging member, a helically wound spring, and a driving connection therebetween for producing axial (engine-engaging) and then rotary movement of said engine-engaging member, of means for compressing said spring, said means including a rotatable cam operating upon said spring in such manner that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows immediately upon completion of the compression thereof, and prior to cessation of rotation of the cam, means for maintaining said cam in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said last-named means including an electric motor, a source of current,

a circuit that remains closed until said cam reaches a predetermined position in its cycle of controller operating upon said spring in such manner that the expansion of the spring, for delivery of starting energy to the engine-engaging member, follows immediately upon completion of the compression thereof, "and prior to cessation of rotation of the controller, means for maintaining said controller in rotation until the spring has been fully compressed, released for expansion, and partially compressed again, said last-named means including an electric motor, a source of current, a circuit that remains closed until said controller reaches a predetermined position in its cycle of rotation, manual means for rotating said controller, and a one-way driving connection between said motor and controller, including one race that remains stationary whenever said manual means is operated.

RAYMOND P. LANSING.