US2782644A - Engine starters - Google Patents

Description

Feb. 26, 1957 Filed March 8, 1954 w. A. WISEMAN ENGINE STARTERS 2 Sheets-Sheet l FIG.I.

Jo o I a INVENTOR.

' WILLIAM A. WISEMAN B www/ ATTO RN EYS Feb. 26, 1957 w. A. WISEMAN 2,732,644

ENGINE STARTERS Filed March 8, 1954 2 Sheets-Sheet 2 (IRAN KSHAF'T INVENTOR. WILLIAM A.WISEMAN ATTORNEYS United States Patent C) ENGINE STARTERS William A. Wiseman, Muskegon, Mich., assignor to Continental Motors Corporation, Muskeg on, Mich, a corporation of Virginia Application March 8, 1954, Serial No. 414,795 Claims. (Cl. 74--7) This invention relates to an engine starter and more particularly .to a starter which is arranged with the engine in a unique, compact and inventive manner.

Normally, starters for engines are arranged in a direct in-line position with the engine, offset the distance of a gear diameter from the centerline of the crankshaft.

makes for a lack of compactness, which, under certain circumstances, limits the usefulness of some engines. The instant invention provides for compactness of the engine assembly, facilitating the addition of desirable accessories, by having the starter arranged above the centerline of the engine and at right angles to a vertical plane passed through that centerline.

It is an object of this in ent-ion to provide an engine starter combination that 1s compact in design.

A further object is to provide a novel engageable and disengageable mechanism coupling the starter and the engine.

A still further object is to provide .a compact enginestarter combination which does not increase the length of the engine.

Other features of the construction will become more apparent as the description of the invention unfolds. below. For a visual understanding of the invention, reference may be had to the accompanying drawings in which like parts are referred to by like reference numerals throughout the several views, illustrating a preferred embodiment of the invention, and in which Fig. 1 is a plan view of an engine and starter therefor embodied according to this invention.

Fig. 2 is an end elevational view taken from the starter end of the engine.

Fig. 3 is an enlarged fragmentary vertical sectional view taken through the engine starting mechanism, indicated generally by the line 33 of Fig. 1.

Fig. 4 is an enlarged fragmentary vertical sectional view taken through the starter mechanism and indicated by the line 4-4 of Fig. 1.

As shown in Fig. 1, engine belongs to that group known as the horizontal opposed type. At one end of the engine and near the top is located the engine starter 12, the axis or" WhlCh is disposed at right angles to a vertical plane passed through the crankshaft axis.

As seen in more detail in Fig. 4, the starter 12 comprises a motor section 14, a starter drive shaft 16 rotatably mounted in a bearing 18 located near motor section 14 and a pilot bearing 20 located at the outer end of shaft 16, a rotatable worm gear 22 slidingly mounted on shaft 16 and guided by key 24, a compression spring 26 and an outer housing 28 containing the starter drive mechanism just described.

Starter shaft 16 has a dovetailed end section 30 arranged to couple with a similar end section 32 on the starter motor core shaft 33. This permits simple assembly and disassembly of the starter drive mechanism. The shaft 16 is arranged with a shoulder portion 34, against which one end of the spring 26 bears. The other end of spring 26 bears against worm gear 22, resisting but not restraining sliding movement of the gear during rotation, and forcing the gear to slide back on its shaft when the rotating torque has been released, i. e. when the starter shaft 16 has ceased its rotation.

Directly below worm gear 22 is arranged the engine starter mechanism comprising an outer housing shell 36, an inner housing shell 38, a shaft 40 having a driving gear 42 thereon at the engine end of the shaft, a driven gear 44 supported on a drum 46 which is rotatable on shaft 40 about a bushing 48, a helically coiled spring 50, and a spring sleeve 52 which is disposed within an opening 51 in the housing shell 38 concentric with shaft 40.

Between gear drum 46 and driving gear 42, shaft 40 supports an integrally formed hub flange 54, which is located within the confines of helical spring 50. Spring 50 is preferably made of square wire in order to provide maximum inner surface contact with gear drum 46 and shaft hub flange 54. Shaft 46 is rotatably located between bearing 56 in outer housing shell 36 and bearing 58 positioned in engine housing 60. Driving gear 42 meshes with crankshaft gear 62 carried by the engine crankshaft supported by the engine housing 60. Outworthy of housing shell 36, projecting shaft 40 may support one or more pulleys 64 to drive such accessories as a current generator 66, etc.

Describing the construction in greater detail, with reference to Fig. 3, it will be noted that shaft 40 is supported at the engine end in bearing 58, driving gear 42 is in mesh with crankshaft gear 62, and shaft hub flange 54 is provided with a fairly large peripheral area under the coil spring 50.

Beyond hub flange 54, the drum 46 containing bushing 48 is rotatable about shaft 40. Drum 46 has an annular flange 68 to which is aflixed driven gear 44, and also, a hub portion 70 having substantially the same outer diameter as that of shaft hub flange 54, which is just coil spring 50'. The remaining turns of spring 50 has ia'n' interference fit over the periphery of hub portion 70 of drum 46 and a slip fit on the periphery of the hub flange 54 of shaft 40. The free end portion 74 of coil spring 50 is encased by sleeve 52 Within an inturned flange 76. Sleeve 52, it will be noted, is held in the starter mechanism housing 28 by a press fit. It is designed for an interference fit with the outer peripheral surface of the coil spi'ing and turns conditions of operation to be described e ow.

The ease of assembly and disas'sembly of the various components of the starter mechanism and its simplicity of arrangement with respect to engine 10 are due primarily to the compactness of structure achieved by this invention.

of worm gear .22 causes driven gear 44 with which it is When rotation is attained, coil spring 50, aifixed to drum 46, and resistin rotation in sleeve I When engine is fully star-ted, starter motor 14 is cut out by a suitable switching device (not shown) and it is allowed to stop. From the time the engine starts rotation under its own power until the starter motor ceases rotating, drum 54 and shaft 40 run ahead of drum 46, the engine then supplying the energy to keep advancing spring 50 in sleeve 52 and allowing spring 26 to push gear 22 ahead of shaft 16, the only load on gear 22 being that required to tighten spring 50 into light contact with drum 54.

vWhen the starter motor and gear 22 cease rotating, there is more energy in spring 50 than in spring 25, equal to the differential between the force required to slip spring 50 in sleeve 52 and the force required to produce contact between spring 50 and hub flange 54. This differential in spring loading now tends to equalize by rotating worm wheel 44 backwards, sliding gear 22 toward the thrust shoulder increasing the compression load in spring 26 to balance a reduced load in spring 50. The reversal of gear 44 and drum 46 causes the spring 50 to unwind and thus the spring 50 becomes disengaged from the hub flange 54.

It will be apparent to those skilled in the art to which this invention relates that various modifications and changes may be made without departing from the spirit of the invention and from the scope of the appended claims.

I claim:

1. In combination, a multi-cylinder engine having a crankshaft operative therein, a crankshaft gear carried by said crankshaft, a starter mechanism for said engine mounted on said engine at right angles to a plane passed through the axis of said crankshaft, intermediate transmission means coacting with said starter mechanism and in mesh with said engine crankshaft gear, said transmission means comprising a rotatable shaft axially aligned parallel to the axis of said crankshaft, driving means on said shaft enacting with said crankshaft gear, a hub flange on said shaft fixed thereon, a drum rotatable on said shaft adjacent said hub flange, driven by said starter mechanism and having fixed thereon a helical coil extending over said drum and said shaft hub flange, adapted to tightly engage said drum and said shaft hub flange when said drum is driven by said starter mechanism.

2. In combination, a multi-cylinder engine having a crankshaft operative therein contained in an engine housing, a crankshaft gear carried by said crankshaft, a starter mechanism for said engine mounted on said housing, intermediate transmission means coacting with said starter mechanism and engaged with said engine crankshaft, said intermediate transmission means comprising a. rotatable shaft, :1 gear on said rotatable shaft meshing with said crankshaft gear, a. drum rotatable on said shaft driven by said starter mechanism, a hub flange fixedly arranged on said shaft adjacent said rotatable drum, a helical coil fixed to the outer periphery of said drum extending over said drum and said shaft hub flange, and a sleeve fixedly arranged concentric with said helical coil and closely adjacent the free end of said helical coil, said helical coil adapted to tightly engage said drum and frictionally engage With said shaft hub flange within said sleeve when said drum is driven by said starter mechanism and adapted to disengage from said shaft hub flange when said starter mechanism is at rest,

3. The combination of claim 2.,and in which said starter mechanism comprises a motor driven shaft, gear means rotatably driven and slidingly mounted on said shaft, and a compression spring adapted to compress under the thrust of said gear means when said shaft is revolving and to slide said gear on said shaft when said shaft is at rest, said gear means being in constant engagement with said drum, the free end of said helical coil being in touching engagement with said sleeve and disengaged from said shaft hub flange when said drum is at rest.

4. The combination of claim 2, and in which an engine accessory is mounted on said engine, and said shaft extends outwardly from said engine housing and is adapted to support engine accessory drive means thereon.

5. The combination of claim 3, and in which said differential in spring loading between the force required to slip said coil spring in said sleeve and the force required to produce contact between the coil spring and the hub flange operable to backwardly rotate the drum and the driven gear carried thereby, whereby to slide said gear means on said starter mechanism motor shaft and in crease the compression in said compression. spring to balance a reduced loading of said coil spring to unwind and to be released from driving engagement with said hub flange.

References Cited in the file of this patent UNITED STATES PATENTS 1,185,197 Hartford May 30, 1916 1,240,422 Coatalen Sept. 18, 1917 1,921,880 Hertz et a1 Aug. 8, 1933 2,511,908 Forbess June 20, 1950 2,644,338 Miller July 7, 1953

Images