US2198826A - Engine starter accelerator - Google Patents

Description

April 30, 1940.

R. P. LANSING ET AL 3,826

ENGINE STARTER ACCELERATOR Original Filed Sept. 29, 1928 Geo/ye J/7ausama/m Patented. Apr. 30, 1940 I PATENT ENGINE STARTER ACCELERATOR Raymond P. Lansing, Montclair, and George J. Hausarnann, Bloomfield, N. J., assignors, by mesne assignments, to Bendix Aviation Corporation, South Bend, Ind, a corporation of Delaware Original application September 29, 1928, Serial 2 Claims.

' Thisinvention relates to starting mechanisms for internal combustion engines, and more particularly to mechanism for use in starting aircraft engines.

For starting internal combustion engines, and particularly aircraft engines, inertia starters are used. In these, an inertia mass such as a fly wheel is set in very rapid rotation, say of the order of 20,000 R. P. M., and then is connected m i with a member of the engine to be started, properly to apply the kinetic energy of the flywheel to cranking the engine. Speed-changing gearing of high order of reduction is interposed between the flywheel and that driving member of the 1 starter which is to be engaged with the engine to crank it and commonly the starter is hand-operable, either as the sole manner of accelerating the flywheel or supplementally to the provision of an electric starting motor, the hand-cranking shaft being usually operatively connected with a low speedmember of the reduction gearing in a position accessible exteriorly of the fuselage of the aircraft.

A primary purpose of the present invention is to provide desirable and effective means for accelerating'inertia starters by power taken from an outside source of electrical supply, thus to avoid necessity for hand-cranking, or the use of the aircraft's storage battery for starting pur- Doses where the starter is of the motor-powered type. 1

Further objects of the invention are to provide a motor-unit of the accelerator equipment in the convenient form of a hand-tool which will be of simple, effective and durable construction, and to combine with such motor-unit such electrical control-equipment as will both safeguard the motor and insure its effective operation to deliver proper initial torque to, and effect sustained acceleration of, the starter for promptly, safely and sufficiently bringing its flywheel speed up to the desired maximum.

Other objects sought, and attained by this invention, will hereinafter become apparent; and 45 in the accompanying drawings are illustrated .constructions and arrangements for embodiment of the invention which have been found in practice to be successful in the stated service In the drawings:

Fig. 1 is a view partly in longitudinal section and partly in elevation of the pertinent portion of a portable unit in which the invention is embodied; and

Fig. 2 is a diagrammatic view showing the unit 309,286. Divided and April 6, 1937, Serial No. 135,312

this ppllcatlon of Fig. 1 in operative relationship to an engine gram of some of its major parts, an inertia.

starter for the engine: parts throughout the diagrammatic views being shown schematically without regard tophysical proportioning thereof or details of commercial construction. In the starter, b is a driving member shiftable longitudinally, as by shipper W, on the starter shaft b to engage the engine member a and rotatable with the non-circular end of such shaft to crank the engine. The inertia means or flywheel b is operatively connected by any suitable reduction gearing b, of high order of reduction, with said shaft 17 which is here shown as being also the hand-cranking shaft and as being provided accessibly with a positive clutch member 17 to receive a complements] part of the motor-unit C of the accelerator-equipment. As herein shown, the motor-unit 0 provides a motor 10 which is connected through reduction gearing Ii with the connector-member l2 that is to be engaged with part b of the starter, thus to gear down the external starting motor l0 and insure that an initial, limited energization of the motor, harmless to such motor, will develop adequate torque to set the starter in rotation and drive its flywheel through the lower range of its acceleration.

To supplement the operators hand as a holding means, pins D are provided on the forward end of the unit C, said pins being engageable with the stationary part of the plane, which stationary part thus acts as'the supporting means for the said forward end of the motor unit.

The armature shaft it of the motor projects through the detachable front wall ll of the casing for coaction with the reduction gearing H which is covered by a gear-housing i8, detachably secured to and forming a substantial continuation of the motor casing IS.

The connector i2 is carried by a stub shaft 20 journaled in the end-structure I. of the gearhousing and is preferably axially yieldable on shaft 20, though rotatable therewith. To this end, cross pin 2! of connector member I2 takes through an axial slot. 22 "of the shaft and is yieldingly held in contact" with the front end of the slot by-a spring 23 housed in an axial bore of the shaft. Correct centering of the-hand-tool and maintenance of driving contact, with respect to starter-part b", are thereby made easy.

The reduction gear II is preferably of planetary type and comprises a fixed internal gear member 25 secured to casing member II, a rotatable internal gear 26, drivably secured to shaft 20, and pinion structures 21 connecting the gears and bodily carried in rotation by the armature shaft ll.

The pinion members 21 are here shown as carried by a frame, the prime element of which is a three-armed spider 29 having its hub keyed to the armature shaft, the spider being flanked by frame rings 30 secured thereto by cross bolts 3i,

and such rings carrying the pintles 32 for the pinion structures 21 disposed between the spider arms. Gears 25 and 28 being of slightly different pitch diameter and number of teeth, each practice.

As shown, the bearing 36 for the shaft 20* takes any and thrust thereon so that the planetary reduction-gearing is not affected thereby, and

substantial ensealing of the gear housing and protection of the bearings is afforded by the suitably-shaped cover-plates 38 and interposed packing 39.

while a particular embodiment of the invention has been shown and described in considerable detail, it will be understood that changes may be made therein without departure from the spirit of the invention within the scope of the appended claims.v This application is a division of co-pending application No. 309,286, flled'September 29, 1 928.

-What we claim is;

1. Ina. portabie'acc'elerator of the type adapted to crank an engine starter mechanism, the combination warns, slotted driving shaft, of a pin extending through said slotted shaft, aspring mounted within said slotted shaft and having one end bearing against said pin to normally maintain said pin at the outer end of the slot in said shaft, and means for drivably connecting said pin with said starter mechanism.'

2. In a portable accelerator of the type adaptedto crank an engine starter mechanism, the combination, with a slotted shaft, of a pin extend- -ing transversely of said slotted shaft, a spring mounted within said slotted shaft and having one end bearing against said pin to normally maintain'said pin at oneend of the slot in said shaft, and fneans for drivably connecting said pin and shaft with said starter mechanism.

RAYMOND P. LANSING. GEORGE J. HAUSAMANN.

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