US2977100A - Throttle operated starter switch - Google Patents

Description

March 28, 1961 H. A. CARLSON THRoTTLE OPERATED STARTER SWITCH Filed Jan. 24, 1958 FIG.|.

INVENTOR. HAROLD A. CARLSON BY T nm/M ATTORNEY United StatesA Patent c Industries, Incorporated, New York, N.Y., a corpora-v tion of New Jersey Filed Jan. 24, 195s, ser. No. 710,902

s claims. (ci. 2in- 39) This invention relates to charge forming means for internal combustion engines. Dwight L. Gordon et al. Patent 2,694,559 illustrates means for relaxing the choke closing tension of the automatic choke thermostat in an automotive carburetor when the throttle valve 'is opened. This action has been found necessary in some carburetor installations due to excessive richness of the mixture during the warmup period when the throttle valve is opened for acceleration. However, the Gordon et al. thermostat relaxing means cannot be used,y for instance, where a throttle operated starting switch,as in Coffey Patent Re. 22,385, is also used, since in partially opening the throttle valve to close the starter switch for cold starting, the thermostat closing tension would be undesirably relaxed.

Consequenly, it is the main object of the present inventionpto provide means whereby a carburetor equipped 2,977,100 Patentedv Mar. 28, 196.1

rice l spring Z3. t The latter bell `crank has a second armV 24 connected by a link 25 to ,the accelerator pedal in the drivers compartment, bell crank 22, 24, of course, being rigidly connected to throttlev shaft 21 for actuation of throttle valve by means of the accelerator pedale: A throttle return spring is shown at 26. f A

vAlso formed on arm 24 is a starter switch actuator 27 which, as illustrated inv Coffey Patent Re.'22,385, acts through a ball 28, and plunger 29, when the associated engine is not running' andthe throttle valveV is opened a predetermined distance, to close switch pointsA 30 and thereby energize the starter-circuit and crankthe engine.

with thermostat tension adjusting means operated by nection between the throttle valve and the choke control thermostat, which, after the engine is started, adjusts ythe thermostat tension, as inthe Gordon et al. patent, together with a choke actuated latch which positively prevents the thermostat adjusting action of the above mentioned yielding operative connection during cold starting. The latch has a lost motion connection to the choke valve permitting breathing of the latter during cranking,

while permitting opening of the throttle to its switch engaging position without atfecting the thermostat tension.

In the accompanying drawings which illustrate the invention:

Fig. l is a side view of an automotive carburetor illustrating the invention, parts being broken away and sec` tioned. Y

Fig. 2 is an isometric, exploded view` showing the parts forming the automatic choke control and interconnection between the choke control and throttle valve.

Fig. 3 is a diagram illustrating the principal parts of the present invention.

First, with reference -to Fig. 3, there is illustrated an ventlon 1n an automotive carburetor.

air inlet member 5 and mixture outlet 6 controlled, respectively, by an unbalanced choke valve 7 and a butterfly throttle valve 8. The choke valve is provided with automatic choke control mechanism, including a coiled thermostat 9 with its inner extremity secured to a rotatable pintle 10 and its outer extremity hooked at 11 to form a one-way connection, through link 12 to a bell crank arm 13 rigidly secured to choke shaft 14. Secured to the other end of link 12 is a suction piston 15 which works in a cylinder 16 connected by a passage 17 to the mixture outlet posterior to throttle 8.

Rigid with pintle 10 is an arm 18 connected by a link 19 to a bell crank arm Z0 loosely received upon throttle shaft 21. A second bell crank has an arm 22 resiliexitly connected to arm Z0 and the thermostat by a coiled In order to permit closing of the starter circuit, vas described, without relaxing the thermostat tension through arm 20 and link 19, etc., a latch 31 is pivotallypmounted. on the carburetor body at 32-and has a-,detent portion 33 for cooperating with an arm 34` onpth/e loose bell crank previously mentioned, to positively preventV clockf wise rotation of this bell crank. The latchhas a lost motion connection to the choke valve through aslotted link 35'- and ,an'arm36. The lost motionin link 35 is sutlcient to permit proper breathing of choke valvey Z during cold cranking ofuthe engine, but causes counterclockwise shifting-,of the latch away from. its -latchiug position as shown, when the choke valve is opened Jsub,- stantially, as when the associatedfengine-starts.to run under its own power. i,

In operation, when the temperature is low, thermostat 9 unwinds so as to resiliently close Yunbalanced choke valve 7. In order to crank `theengine,the accelerator pedal is depressed 'to partially open throttle 8 and cause closing of starter switch points 30. .After starting of the engine, as taught in Coffey Re. 22,385, the accelerator pedal is released by the operator, whereupon ball 28 is lifted by engine suction so that, thereafter, movementlotf the accelerator has no yelfect upon the starter `switch as long as the engine is running. n i g vAt the s ame time, the pressure differential created on opposite sides of unbalanced choke valve 7 and alsoon opposite sides of suction piston 15, causes opening of the choke Valve to a predetermined position;v Slotted con# nection 35 is designed to permit adequate :breathing `of Ithe choke valve for cranking action to insure proper start-y ing, while causing clockwisey shifting of Athe -latch when the engine starts to run to release bell crank 20, 34. However, during the cranking actionpwhen theflatch is as shown in Fig. 3, the throttle canbe ,opened independently of and, therefore, without affecting the-thermo stat adjusting linkage. After star-ting, when bell `crank 20,

34, is released vby the latch element,- opening of ther throttleV valve causesy clockwise rotationof bell crank 20, 34, and, through linkage 19, 18, tendsto relax ,the choke closing tensionof the thermostat, as taught in theabove mentioned Gordon et al. patent. Latch31, ofcourse', will b e held in its unlatched position under allrunning conditions.V Y f v fr l Figs. land 2 show a practical embodimenhof theinj Like parts'are given the same reference numerals asin Fig. `3 with the letter a. Thermostat mounting pintle 10a is shown slightly disaligned from choke shaft 14a. Latch 31a has an eccentric toothed portion 40 forming the 'usual' fast idle cam for cooperation with an adjusting screw 41 carried by` ythrottle lever 22a mounted on throttle shaft 21a. Link 35a has a lost motion connection with choke shaft 14a through a clevis 42 secured to the choke shaft by a set screw 43 in a collar 44. Lever '36o is Yrotatableon the choke shaft, within the limitsof clevis 42, which ,is suflicient to permit breathing of the choke valve during cold cranking when screw 41 Vis against and holdsfast idle camv40. Y 4 g f Loose disk 20a on the ,throttle shaft is resiliently conf neet'ed to a tight lever 22a by a torsion spring 23a. Lever 22a has an aperture 43 for connection to accele- T3101 pedal. A tingver44 projecting axially from the p'eriplieryof'loose lever 20a is secured "at its extremity `liiik 19a which is connected through a level-18a to adjusting pintle `a at the center of the thermostat. An arm`45, projecting fromthrottle operating lever 22a'is in position to engage an axial, peripheral lug 46 on fast idle member 31a, 4G, when the throttle valve is substantially fully opened, to cause counterclockwise rotation of this fast idle member and, through 'link 35a, partial opening of the 4choke valve, in the well known manner, forunloading in case the manifold should become excessively charged with fuel during cold cranking. A second lug 3311,',also "projecting axially from the periphery of the fast idle member, serves as a latching detent for interfering with "a finger 34a on loose-lever 20a to latch the looselever and thermostat adjusting linkage when the chock'v'alve is closed for cold starting. After the engineY starts to` run under its own power, the choke valve moves suiciently to shift the fast idle member and latching detent to release loose lever a, as above described. Throttle shaft has a slot 27a for operating the' starter, as taught in the above mentioned Coiiey reissue p-atent.

Fig. `l shows a housing 50 which receives the thermostat and suction piston 15a. A threaded boss 51 provides for the supplying of hot air to the thermostat housing, for heating the thermostat, and, thence, past suction piston 15a to the manifold. Also mounted on the lower part of the carburetor body isgthe starter switch mechanism, generally indicated at 52, which cooperates with the throttle shaft -as described in the above mentioned Coffey reissue patent.

Conventional carburetor fuel feeding elements,'also, are shown in Fig. l. The fuel is supplied through an inlet 53 toa float operated constant level chamber 54 and, thence, through a lmain metering orifice element 5S, controlled by 'arnetering pin 56, to a main supply nozzle 51 discharging into primary venturi tube 58 within the mixture-conduit -anterior to the throttle and, through an idle'meteringtube 59to ports't and614 adjacent and posterior to the edge ofv the throttle valve when closed.

` The above describedvdiagrammatic representation and practical embodimenty are illustrative only and exclusive use 'of lall modifications-as come within the scope of the appended claims is contemplated.

I claim: t

l 1V.v Charge forming means for an internal combustion engine comprising'a mixture conduit, choke and throttle valves therein, a thermostat for affecting the action of said choke valve, a device operatively connecting said throttletvalveand said thermostat and adapted to adjust saidV thermostat in accordance with positioning of said throttle valve, mechanism including Ia stop movable to a position to engage and prevent thermostat adjusting action of said device when the choke valve is closed for cold starting, and means responsive to operation of the engine for shifting said-stop away from said position to release said device for thermostat adjusting action thereby.

y2. Charge forming means as described in claim l in which said thermostat adjusting device is yieldingly connected to said throttle valve to permit -action of said throttle valve independently of said adjusting device when said device is engaged by said stop.

3. Charge forming means for an internal combustion engine comprising a mixture conduit, choke and throttle valves therein, a thermostat for closing said choke valve for cold starting,` a device yieldingly connecting said throttle valve `and said thermostat and operative after startingof the engine for adjusting the force applied by'said thermostat to said choke valve as said throttle valve is opened, and mechanism forming an operative conhection "between sid'device and said choke valve,

said mechanism including a stop to engage `and lock-said device against movement during initial opening movement of the throttle valve when said choke valve is in its closed cold starting position.

4. Charge forming means as described in claim 3 in which said mechanism includes a lost motion connection between said choke valve and said stop to permit limited movement of choke valve without affecting said-device.

5. Charge forming means for an internal combustion engine comprising a mixture conduit, choke and throttle valves therein, an automatic control for said choke valve for closing the same for cold starting, a device operatively connecting said choke control and said throttle valve for adjusting said control in accordance with the position of said throttle valve, a latch to engage said device, and a lost motion connection from said choke valve to said latch, said latch mechanism Ibeing operable to prevent choke control adjusting action of said device when said choke valve is in its starting position.

6.- Charge forming means as described in claim 5 in which said latch positively prevents choke control adjusting action of said device when said choke valve is closed for cold starting, and said lost motion connection between -said choke valve and said latch permits limited movement of said choke valve during cold starting of the engine, said choke valve acting through said connection to move said latch out of engagement with said device responsive to starting of the engine.

7. Charge forming means for an internal combustion engine comprising a mixture conduit, choke and thro-ttle valves therein, a thermostat for urging said choke valve closed for cold starting, a device operatively connecting said throttlevalve and said thermostat for adiusting the choke valve closing force of said thermostat .as said throttle valve is opened, a latch to engage said device when said throttle valve is `closed for preventing thermostat adjusting action of said device when said choke valve is'in its cold starting position, a lost motion operative connection between said choke valve and latch for moving said latch to release said device after said choke valve has been substantially opened,said device including yielding means whereby said throttle may be opened to its-starting position when said device is latched by said mechanism.

8. Charge forming means. for an internal combustion engine comprising a mixture conduit, choke and throttle valves therein, a thermostat for urging said choke valve closed for cold starting, a device operatively connecting said throttle valve and said thermostat for adjusting the choke valve closing force of said thermostat `as said throttle valve is opened, a latch to engage said device when said throttle valve is closed for preventing thermostat adjusting action of said device when said choke valve is in its cold starting position, a Vlost motion operative connection between said choke valve and latch for moving said latch to release said device after said choke valve has been substantially'opened, said device including yieldv ing means whereby said throttle may be opened to its starting position when said device is latched lby said mechanism, and a starting control operativeiy connected to said throttle valve for actuation when said throttle valve is opened to its starting position.

References Cited in the le of this patent UNITED STATES PATENTS.

Re. 22,385 Coffey Oct. 26, 1943 2,609,806 Winkler Sept. 9, 1952 2,694,558 Jorgensen et al Nov. 16, 1954 2,694,559 Gordon Nov. 16, i954 V2,719,706 Winkler Oct. 4, 1955 2,746,439 Hunt May 22, l956 2,793,634 Ericson May 28, 1957 2,834,586 Szwargulski -g May 13, 1958

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