US2727590A - Portable engine starter - Google Patents

Description

Dec. 20, 1955 w. H. MATTOX 2,727,590

PORTABLE ENGINE STARTER Filed Aug. 27, 1954 nwz/vroe WE Ma #02:

ATTORNEY Unit-6d Stems Fame 2,721,590 PORTABLE ENGINE STARTER Wyatt Homer Mirttox, Cambridge, Ohio Application August 27, 1954, Serial No. 452,503

2 Claims. (Cl. 18541) This invention relates to devices for starting small internal combustion .engines, particularly miniature engines of the type employed in rotating the propellers of models of airplanes of diminutive scale.

The primary object of the invention is to provide a portable, lightweight, spring motor-actuated starter device for miniature airplane engines, and wherein the device embodies a frame from which rigidly projects a handle, the latter being formed so that it may be held by one hand of an operator in maintaining a rotatable adaptor of the device in rotating contact with an engine shaft carried propeller, while the other hand of the operator is used in the support of the toy airplane containing the engine, whereby upon finger actuation of a latch means, mounted in connection with the handle, the power contained in a frame mounted key-wound spring motor may, through associated motion-multiplying gearing, cause spinning movement of the adaptor and the propeller and engine shaft separably joined therewith.

For a further understanding of the invention, reference may be had to the following description and the accompanying drawings, wherein:

Fig. 1 is a perspective view disclosing my improved engine-starting device when held in operative association with a propeller on the engine shaft of a miniature airplane motor and in a position to spin the propeller in starting the engine;

Fig. 2 is a top plan view of the starter device itself;

Fig. 3 is a fragmentary vertical longitudinal sectional view on'the line 33 of Fig. 2;

Fig. 4 is a vertical transverse sectional view on the line 4-4 of Fig. 2.

Referring more particularly to the drawings by reference characters, the numeral 5 designates my improved engine-starting device in its entirety. In the single embodiment'illustrated, the device comprises a frame 6 which includes spaced front and back plates 7 and 7a, respectively, rigidly united by transversely extending spacing bolts 8. A removable cover plate 9 is employed in conjunction with the plate 7 of the frame to form a casing or enclosure in which the spring motor 10 and the motionmultiplying drive gearing 11 of the device are contained in a protected manner.

The spring motor is formed in this instance to comprise a pair of spirally arranged clock springs 12. The outer end of each of these springs is anchored on the cross bolt 8a of the frame, while the inner end of each spring is fixed to a motor shaft 13, journaled for rotation in the frame. This shaft has fixed thereto a ratchet wheel 14, the peripheral teeth of which are engaged by a spring-pressed pawl 15 which is pivoted as at 16 on the side of a gear 17 which is loosely mounted on the shaft 13 and is disposed between the ratchet wheel 14 and a side wall of a stationary case 18. A pair of these cases is carried by the side plates 7 of the frame in position to surround in spaced order the spiral springs 12 of the motor 10 to guide and protect the same.

The teeth of the gear wheel 17 engage with those of 2,727,590 Patented Dec.- 20, 1955 a relatively small pinion 1.9 fixed on an intermediate part of a drive shaft 20, the latter having end portionsv journaled for rotation in aligned openings formed in the side plates 7 of the frame structure of the device, the shaft 20 being disposed in parallel relation with'the motor shaft 13. In this instance, the motor shaft has one end thereof extended beyond the front plate 7 and has securely fastened thereto the hub portion of a winding key,21. The latter is generally spaced from the front plate 7 but at one end thereof includes an inwardly curved finger 22 which is adapted to engage with a fixed stop member 23 projecting outwardly from said front plate, and which serves to limit the rotation of the key and its associated motor shaft 13 to about one complete turn ineither direction of rotation thereof. 3

Secured to the front plate 7 of the frame structure of the device is the bracket-shaped inner end 24 of a handle bar 25. This bar is arranged so that it avoids interfering with rotation of the key 21 and extends from the upper marginal part of the frame structure in perpendicular relation to the vertical plane of the wall 7 and above and in the vertical plane of the drive shaft 20, as shown in Fig. 2. The extreme outer end of the bar carries in depending relationship thereto a handle member 26 which is shaped so that it may be gripped in one hand of a user in the manipulative support and use of the device.

The inner end of the lever 28 has attached thereto the upper end of a vertically depending rod 30, the lower end of this rod, as shown in Fig. 3, being laterally offset and received within an eye formed in the outer end of a rigid crank arm 31 carried by' a sleeve 32 rotatably mounted on a cross bolt 8b of the frame structure. The sleeve is further formed to include a latching detent 33 which, by the action of a spring 34 arranged beneath the thumb button 29 of the lever 28, is normally maintained in contact with the teeth of a latching gear 35 fixed to the drive shaft 20.

One end of the drive shaft, as shown in Fig. 3, projects beyond the back frame plate 7' and is fastened in a bore formed axially in an adapter arm 36. At positions spaced equidistantly from its axis the arm 36 carries fixed threaded studs 37. These studs have headed outer ends and the shanks thereof receive sleeves 38 of a compressible material. The outer end of the axial bore of the adapter arm includes a socket 39 formed to receive in a centering manner the outer end of an engine shaft 40 of a midget-size internal combustion engine 41, the latter being of the type adapted for mounting on the frame of a miniature airplane, as indicated at 42, in rotating the propeller 43 thereof.

In using the device to start an engine, such as that indicated at 41, the key 21 is rotated to wind and tension the spiral spring 12 of the spring motor 10. During and folowing such winding, the motor and drive shafts 13 and 20, respectively, are held against rotation by the engagement of the detent 33 with the teeth of the latching gear 35. With the motor thus wound, the handle member 26 of the device is grasped by one hand of the operator and the entire device bodily manipulated so that the outer end of the engine shaft 40 will be positioned in the centering socket 39 of the adapter arm 36, and with the sleeve-protected studs 37 of said arm arranged in engagernent with opposed edges of the blades of the propeller 43 at positions spaced radially outwardly from the engine shaft. When the device has been thus separably coupled with the propeller, the detent lever 28 is rocked by thumb pressure applied to the button 29 in a downward direction against the force of the spring 34. This results in turning the sleeve 32 and lifting of the detent 33 so that the outer end of the detent is removed from latching or restraining engagement with the teeth of the gear 35. The resultant release of the drive shaft 20 enables the latter to turn rapidly through a desired number of revolutions, as controlled by the tooth ratio in the gearing 17 and 18, in order to spin the propeller 43 under mechanical energysupplied by the spring motor in causing" starting of the engine 41. In this operation, the starting device may be held in the right hand of the operator and the model airplane in the left hand, thus holding" these units in properly joined but readily separable'relationship. My improved starting device has the advantage of being simple in its construction and inexpensive to produce and provides a safe, convenient and positive means for starting small engines of the type defined. The pawl 15 and the ratchet 14 function after the manner of an over-running clutch in relieving the spring motor of strains resulting from the starting of an engine while the propeller thereof is coupled with the device.

I claim:

1. A portable power-furnishing appliance, comprising: acasing; a key-wound spring motor positioned in said casing, said motor including a rotatable driving shaft; a ratchet wheel fixed to rotate with said driving shaft; a gear wheel freely rotatable on said driving shaft adjacent said ratchet wheel; a spring-pressed pawl pivotally mounted on one side of the gear wheel for engagement with the teeth of said ratchet wheel to produce rotation of the gear wheel when the driving shaft is rotated in 4 one direction; a power-take off shaft journaled in said casing-in spaced, laterally offset, parallel relation with said driving shaft; a pinionfixed on said power-take off shaft, the teeth of the pinion being in constant mesh with those of the gear wheel on the driving shaft; an escapement gear fixed to said power-take off shaft; pivoted detent means carried by said casing normally engaged with said escapement gear to hold the power-take off shaft against rotation under the influence of said spring means; a handle rigidly carried by said casing and projecting laterally therefrom in approximate registry with said power-take off shaft; and spring-pressed lever means pivotally carried by said handle for controlling the release of said escapement gear through the removal of the detent means from engagement therewith.

2. A portable power-furnishing appliance as specified in claim 1, and wherein said driving shaft is formed at one end and exteriorly of said casing with a spring-winding key; and a rigid stop element formed with said casing for limiting turning movement on the part of said key.

References Cited in the file of this patent UNITED STATES PATENTS

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