US2770691A - Starter switch - Google Patents

Description

Nov. 13, 1956 A. H. WINKLER STARTER SWITCH Filed Nov. 27, 1953 l2 Sheets-Sheet l ATTORNEY Nov. 13, 1956 A. H. WINKLER STARTER SWITCH 2 Sheets-Sheet 2 Filed Nov.' 27; 1953 5 www United States Patent O STARTER SWITCH Albert H. Winkler, Elmira, N. Y., assiguor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application November 27, 1953, Serial No. 394,774

6 Claims. (Cl. 200--61.9)

The present invention relates to an electrical switch and more particularly to a switch for the electrical starting circuit of an automobile engine.

A number of present automobile models have an electrical starting switch mounted on or associated with the carburetor and actuated by the throttle control mechanism. The switches are so constructed and arranged that when the operator depresses the accelerating pedal in the engine starting operation, the switch closes energizing the starting motor. The engagement of the y wheel by the starter motor causes the engine to move or vibrate on its shock mounts relative to the frame and throttle linkages, which results in a movement of the throttle linkage relative to the starter switch whereby unsatisfactory or intermittent starting motor operation and arcing of the starter switch contacts is obtained. The same unsatisfactory results are obtained should the operator depress the accelerator pedal enough to just make electrical contact and then proceed to move his foot up and down slightly so as to make and break the electrical connection. It is therefore one of the principal objects of the present invention to provide a starting switch of the aforesaid type which has incorporated therein a delayed action mechanism such that vibration of the engine cannot interrupt the starting motor operation. Another object is to provide a starting switch having a delayed action mechanism which will prevent immediate opening of the switch the moment the operator lifts his foot from the accelerating pedal and which will prevent immediate reclosing of the switch after it has once opened. Further objects and advantages of the present invention will become apparent from the following description and accompanying drawing, wherein:

Figure 1 is a cross-sectional view of a switch for a starting circuit of an engine, sh-own mounted on the side of a carburetor adjacent the throttle;

Figures 2, 3, and 4 are cross-sectional views of the switch showing the elements thereof in various operating positions;

Figure 5 is a fragmentary cross-sectional view of the switch showing a modification of my invention; and

Figure 6 is a perspective view of the carburetor shown in Figure 1 with portions cut away to show the interior construction and arrangement of the various parts.

Referring more specifically to the drawing, a starting switch 10 embodying my invention is mounted on a downdraft carburetor 12 which for the purpose of the present description may be considered a conventional oat type automotive carburetor containing the usual main fuel discharge system, idle system, economizer system and accelerating pump. In Figure 1 yonly an induction passage 14, primary and secondary venturis 16 and 18 and a throttle 20 mounted on throttle shaf-t 22 are shown. The throttle is actuated by the operator through an accelerating pedal and a linkage, shown in part at 24, connecting said pedal to the throttle shaft on the left hand end thereof as shown in the drawing. Certain features ofthe switch shown in the accompanying drawing fice are covered in my Patent No. 2,492,340, issued December 27, 1949.

The switch is mounted on the side of the carburetor and includes a body 30, an electrical non-conducting cap 32 secured to the body by bolt 34 and spring clip 36, two stationary electrical contacts 38 and 40 mounted in said cap on opposite sides of the hollow interior thereof, and a movable U-shaped contact 42 in said cap mounted on a piston 44 of non-conducting material. The piston is moved upwardly and downwardly in the cap by a stem 46 which extends over and under said piston and which is moved in the switch closing direction by a coil spring 48 reacting between the upper end of said stem and the underside of cap 32 and in the switch opening direction by a lever 50 rigidly mounted on the end of throttle shaft 22. The stem is held in its uppermost position by lever 50 when the throttle valve is closed. With the stem in this position the ends of movable contact 42 are out of engagement with the stationary contacts.

The slot 52 of stem 46 in which piston 44 is disposed is made somewhat longer than the piston in order to provide a lost motion connection between the stem and piston. With this arrangement, the stem must travel a short distance before it moves -the piston in either the switch closing or opening directions, causing a delay in the response of the starting switch to the movement of the accelerating pedal by the operator, or movement of throttle linkage relative to the switch due to engine vibrations. If the operator should quickly move the accelerating pedal up and down or if engine vibration causes the throttle lever to rapidly engage and disengage the stem, the lost motion connection in the switch prevents the interruption of starter motor operation.

In order to prevent closing of the switch after the engine has commenced to lire, a vacuum responsive piston 60 disposed in a cylinder 62 of the main body is adapted to move through a slot 64 in stem 46 to preven-t the stem from descending when the throttle is opened. The piston is moved in the direction to prevent movement of the stem by vacuum transmitted from induction passage 14 on the engine side of the throttle by passage 66 and in the direction to permit movement of the stem by a coil spring 67 reacting between one end of the piston and the vacuum end of the cylinder. When the piston is in the right hand end of the cylinder a deep annular groove 68 is inline with stem 46 such that said stem can move downwardly to the switch closed position. After the engine has been started and the throttle closed the manifold vacuum moves the piston to the left hand end of cylinder 62. Thereafter when the throttle is opened while the engine is running, stem 46 seats in a small annular slot 70 which prevents the stem from moving downwardly suiiiciently to close the switch. The stem in groove 70 also prevents the piston 60 from returning to its nonetfective position when the manifold vacuum is dissipated by moving the throttle to wide open position. When the stern is again raised from slot 70 as the throttle approaches closed position, the manifold vacuum will normally be sufficient to hold the piston in the position shown in Figure 3.

When the operator prepares to start the engine, the throttle is closed, the stem 46 is up and the switch is open, as shown in Figure l. When the accelerator pedal is depressed and the throttle opened, stem 46 moves downwardly into annular groove 68 and the switch closes, as shown in Figure 2. After the engine begins to tire, the operator closes the throttle which in turn lifts stem 46 and opens the switch. The piston is then free to move under the inuence of manifold vacuum through slot 64 to the left hand end of cylinder 62, the position shown in Figure 3. When the throttle is thereafter opened the stem 46 seats in groove 70, as shown in Figure 4 and retains the switch in open position and the piston to the left regardless of the degree of vacuum in the manifold.

In the modiiication of my invention shown in Figure 5, the piston 44 lits snugly in the slot 52 of stem 4.6. Lost motion connection is provided between U-shaped contact 42, slidably mounted on rivet 75, and piston 44. With exception of the location of the lost motion connection the details and operation of the switch are the same as described with respect to Figures 1 through 4.

Various changes can be made in the present switch mechanism embodying the delayed action feature without departing from the scope of the present invention,

I claim: l

l. An electrical starting switch for an internal combustion engine having a throttle, comprising a stationary contact, a movable contact, a piston connected to said movable contact, a stem, a slot in said stem of greater length than the piston adapted to surround said piston and provide a lost motion connection therewith, a spring urging said stem in a switch closing direction, a throttle actuated lever for moving said stern in a switch opening direction, a second slot in said stem, a vacuum actuated piston in said second slot, a rst annular groove in said vacuum piston adapted to receive said stem when the switch is in a closed position, and a second annular groove in said vacuum piston adapted to receive said stem to hold said switch in an open position.

2. An electrical starting switch for an internal combustion engine having a throttle, comprising a housing, a non-conducting cap for said housing, a pair of stationary electrical contacts in said cap, a piston in said cap having a substantially U-shaped contact adapted to engage said stationary contacts7 an actuating stem for said piston, a lost motion connection means between said stem and piston, a spring urging said actuating stem in a switch closing direction, a throttle actuated lever for moving said stem in a switch opening direction, and

vacuum actuated means for holding said stem in a switch open position during engine operation,

3. ln an electrical starting switch for an internal combustion engine having an induction passage with a throttle therein: a housing having a chamber therein, electrical contact elements exposed in said chamber, a movable switch member in said chamber, actuating means for said member, a spring urging said actuating means in a switch closing direction, a throttle actuated lever urging said actuating member in a direction to open said switch, and a means for delaying the response of said switch member to said actuating member.

4. An electrical starting switch for an internal combustion engine having a carburetor with a throttle therein, comprising a housing, tixed electrical contacts in said housing, a piston of non-conductingmaterial in said housing, an electrical contact connected to said piston for engaging said Xed contacts, an actuating member eX- tending over and under said piston, a spring urging said member in a switch closing direction, a throttle actuated means urging said member ina switch opening direction, and means for delaying the response of said piston to the movement of said actuating member.

5. An electrical starting switch for an internal combustion engine having a carburetor with a throttle therein, comprising a housing, iXed electrical contacts in said housing, a movable electrical contact in said housing, means responsive to throttle movement for actuating said movable contacts, a two way connection between said actua-ting means and said movable contacts, and lost motion means between said actuating means and said movable contacts.

6. An electrical starting switch for an itnernal comb-ustion engine having a carburetor with a throttle there-t in, comprising a housing, xed electrical contacts in said housing, a piston of lioirconducting material in said housing, an electrical contact having a lost motion connection with said piston for engaging said xed contacts, an actuating member for said piston, resilient means urging said member in a switch closing direction, and throttle actuated means for opening said switch.

References Cited in the tile of this patent UNITED STATES PATENTS 1,309,926 Y White et al. July 15, 1919 2,492,340 Winkler s Dec. 27, 1949 2,521,561 Batcheller Sept. 5, 1950 2,611,841 Boyce Sept. 23, 1952

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