US2668916A - Engine starting apparatus - Google Patents

Description

Feb. 9, 1954 C; DERMOND 2,668,916

ENGINE STARTING APPARATUS Feb. 9, 1954 C. DERMQND 2,668,916

ENGINE STARTING APPARATUS Filed Jan. 22, 1952 2 Sheets-Sheet 2 fm/Hmm C55/aww@ BY X QD Mam M "fw /775 4free/M75 Patented Feb. 9, 1954 UNITED PATENT OFFICE toI General MotorswCorporation, Detroit, Mich.; a: corporation of Delaware,

Application January 22, 1952,V SerialNo. 267,652

TinsV invention relates to engine starting apparatu's and particularly to the semi-automatic type of starting apparatus in which the control circuit therefor is closed normally to effect operation ofthe starting motor but in which closing of the control circuit is automatically prevented when the engine is self-operative.

A starting apparatus of this type is shown in the copending applicati-on of Paul L. Schneider', Serial No. 233,031', led June 22, 1951, and the present invention is inthefnature of an improvementon the'd'evice disclosed therein and includes various improved details of construction, particularly in the control switch which is effective to control operationof the apparatus. @ne of` the" features of the present invention is a movable contact member which is loose on its operating shaft so that the shaft makes a predetermined i'dl'efmovement" from its closed or open position before it picks up the contact. A fur"- ther feature ofY improvement is the' provision of al piston which is directly operated' byl engine suction to prevent the closing of' the starter control circuit during operation of the eng-ine under its own power and which is held in engagement with the movable contact by a spring so as to hold the contact against movementv untilf posi'- tively movedpyv its operating shaft.

A still further feature of the invention a means which enables a less amount ofl engine suction tohold the said piston in the position to which it is moved to prevent closing of the starter control circuit than is required to move it tosuch position.

Further' objects and advantages ofthe present' invention will he apparent from the` following description, referencev being had to the accompanying drawings wherein a preferredembodiment off the present invention is clearly shown.

In the drawings:

Fig; I isa diagrammatic View of a starting' apparatus having a control switch constructed in accordance with the present invention,

Fig; 2 is a vertical section showing the control switch attached to theA carburetor with which it is associated.

Fig. 3 is a section on the line 3-3 of Fig. 2.

In. Fig. i the entire control circuit of a starting` apparatus in which the control switch of the present invention is adapted to be used, is shown. in such figure, 20' designates a generator grounded 2| and connected by a wirey 22 with. theI current winding 23 of a reverse current/relay' 2d. tilinding 23 is' connected withthe frame 2E of relayy 24, whichv frame Asupports al 2-y i leaf spring hinge 26 to which one end of' the armature 2,1 is attached.. Armature 21 carries a contact, 28 engageable with its stationary contact 29 carried by bracket 3G connected by wire 3| with an ammeter 32 connected by wires V3i!" and 34 with the battery 35 grounded at 36; This completes the generator-to-battery circuit. A voltage coil 3l is connected with the relay frame 2t, and is grounded. at 38'. The frame 25 supports a core 39 which is surrounded bythe windings. 2.3 and 3l although these windings are shown in the drawing. as separatedv from the core 391. The relay contacts 23 and'29` are closed to complete the. battery charging circuit by the magnetic action produced by current flowing through. the voltage winding 3l after the generator has attained a certain voltage. When. the contacts 2S and 29 arel closed, currentthen hows throughv the windingZ which then cooperateswith winding 3T to hold the' armature 2'1 in position to maintain the contact 281 in engagement with the contact 29. It is therefore apparent that the relay can be adjusted so that its contacts will not be separated due to the action of the spring.

2h hinge 26 until after the, voltage of the generator,

has fallen substantially below that voltage required for the closing of' the relay contacts 28 and 29.

The mainy engine cranking circuit comprises the battery 1.25, wire 34 switch contact Ml, movable contact 4l, switch contact 42, wire 43, startingv motor M which is groundedl at 45, and battery ground connection 35. The starting motor M operates the shaft 46 along which slides a sleeve il which is splined on the shaft AB and which is operatively connected through a oneway or overrunning clutch 48 with a pinion t9 engageable with the engine ywheel gear 5t. The sleeve 4l is surrounded by a grooved collar tl which is siidahle. along the sleeve 4l but normally is held against a shoulder 52 at the left end of the sleeve 4l by a spring 53 interposed between thev collar 5I and the clutch 118. The collar '5i is causedl to move toward the right in the drawing by lever 5,4. pivotally mounted upon a shaft 55 and carrying at its lower end a pin 56 received by the groove of the collar 5i. Movenient of the lever 54 counterclockwise will cause the sleeve il tov be moved toward the right and 'the pinion it to become engaged with the iiywheel gear 5t; The pinion t9 is withdrawn from the gear 5t by the operation of a spring, 57 which surrounds the' shaftA 55 and bears at one end against a stationary stop Strand at the other against a stop 59 carried by the lever 54'.

The lever 5t is actuated and the switch 4E, 4I, i2 is closed by electromagnetic means which comprises a solenoid core Eil and a solenoid armature El which are surrounded by electromagnetic: windings t2 and The solenoid core Elli is provided with a central bore for receiving a horizontally slidable plunger` or rod 54 on which the Contact il is moi/ably supported between two springs solenoid. armature 5i is connected by a pin 'll with a link 'i5 which yCarries a stud 'i5 received by a slot 'il provided in the upper end of the lever 513.

When suicient current passes through the windings (i2 and t3, the armature 6I is caused to move toward the left in order to effect counterclockwise movement of the lever 56 and the movement of the pinion ,i9 into mesh with the engine gear This movement of the solenoid 6I also causes the rod to move to the left carrying with it the switch contact 4i which is yieldingly pressed into engagement with the contacts 49 and f1.2. When this occurs, current will flow from the battery to the motor lill, thereby causing rotation oi its armature shaft 46 and the pinion t9 driven. thereby through the splined sleeve d1 and the overrunning clutch 423, thereby causing the fiy-wheel gear 59 to rotate and the engine to be cranked for starting purposes. Should the engine fail to start and the pinion 49 fail to be withdrawn from the fly-wheel gear 50 by the action of the spring 5l, it is possible to open the circuit of the starting motor by disconnecting the magnet coil windings t2 and 93 from the storage battery, the connections to which are to be described later. G3 are deenergized, movement of the contact 4I away from the contacts ill and 42 may take place due to the fact that the solenoid SI may move toward the right slightly although the lever 54 may not be turned. This is possible due to the lost motion connection provided by the pin 'i6 and the slot il between the solenoid armature iii and the lever 54.

Should the end faces of the teeth of the pinion 49 abut with the end faces of the gear 59 before meshing, it is possible to close the motor circuit in order that the pinion 49 may be rotated into meshing relation with the engine gear 50. rThis is possible due to the fact that the switch contacts lill, 4l, l2 can be closed before r the meshing of pinion 49 with gear 59 takes place. The solenoid armature iii moves to close the motor switch and to move the pinion 49 toward the E9; but, after the pinion 49 collides with the gear @El yond its initial state of compression. Then when the motor shaft turns to relieve the condition of gear tooth abutment, the spring 53 is released quickly to snap or jump the pinion 49 into engagement with the engine gear 5U.

The circuit for connecting the magnet windings 62 and S3 with the storage battery 35 comprises the following circuit; battery 35, wire 34, Contact 40, frame 9! of the starter control relay I99, leaf spring hinge 92, armature 93, contact 84, stationary contact bracket 96, wire 3l, winding 63, ground connection dit and battery ground connection 39. The circuit of the other winding 92 includes the foregoing circuit as far as the bracket 55. From the bracket a wire 99 leads out to connect with the coil E?. which is connected by wire 98a with the contact d2. The circuit of coil 52 is completed to the battery through the motor 4 4 and ground connections 45 and 35. It is apparent that when the contacts 84 and 85 of the When the magnet coils 52 and the spring 53 is compressed bestarter relay are closed, current will now through both windings 62 and 63 to cause the solenoid 6I to move toward the left in order to shift the pinion 49 into engagement with the gear 50 and to close the switch contacts i0, 4l, 42. When the motor switch closes, the winding 62 will be short circuited. The winding 62 is made preferably of relatively coarse wire whereas the winding 63 is constructed of relatively ne wire. Both windings E2 and 63 are required to draw the armature 5I across to the core 59 but, when this relation has been established, the one winding 63 is all that is required to maintain this relationship. Therefore, the winding G2 which consumes the greater amount of current is short circuited so that the starting motor will have adequate current for cranking the engine.

The operation of the relay 8i) is controlled in part by the ignition switch 93 and a switch 94 which are in series, the switch being closed by the carburetor throttle to effect starting and prevented from closing during engine operation by action of engine suction. To this end, one terminal of the ignition switch is connected to the wire 3I leading to the battery, by a wire 95, while another terminal 91 is connected by wire 98 to one of the contacts of the switch 54, while another contact of this switch is connected by wire 99 to the winding I 90 of the relay 80 and this winding is connected by wire IlJI with bracket I02 supporting contact I03 adapted to engage contact E94 carried by bracket 2l of the cut-out relay and connected by wire I95 with the ground connection 33. The movable contact |06 of the ignition switch will engage terminals 95 and 9'! when the switch is closed and obviously when the contacts H13 and Ili are in engagement with the ignition switch and switch 94 closed, the winding |00 will be energized. This will cause engagement of contacts 84: and S5 and operation of the main magnet to close the starting motor circuit. When contacts I 93 and E04 are separated by action of the generator, the winding 80 cannot be energized and the starting motor circuit cannot be closed.

The control circuit above-described is just the same as shown in the aforementioned Schneider application, but the switch 94 is of quite different construction from that shown in such application. The switch 94, as disclosed herein, includes a housing I I9 which may be secured in any desirable way to a boss IlI extending from the throttle outlet casting I i2. As shown, the boss has a recess formed thereon into which an annular boss II3 extending from housing III), fits. In the boss I I3 is a bushing I Ill and extending through the bushing is the shaft I I5 on which the throttle valve IIS is secured. A removable plate of suitable insulating material I i1 closes one end of the housing IIll and when removed permits access to the interior of the housing I I0.

Suitably secured in the plate Il are binding posts II8 and iii! connected respectively with the wires 98 and 29 and connected to these binding posts are contacts I 29 and l2! both of which must be engaged by a movable contact i122 in order to effect energization of the r arting motor. This contact is a strip of metal suitably attached to and supported by a block of insulating material I 23 rotatably mounted on a reduced portion I24 of the throttle shaft, and having an arcuate peripheral surface at a greater distance from the axis of shaft i i5 than the contact |22, such surface being normally engaged by the contact I29 as shown in the drawings.

The dosing of' the' cant-roi fortuit is effecten` by vcouriterckiki-kwise rotation' Ioi the block |23', assnn Figz. 27,tdperrnit'fthe Contact |2U,-Whi`oh is'biasd towards the left, toA move olf the surface |25 and snap into engagement with the contact |22,- -which always engages contact |2| in any position of the block |23. Rotation of the block |23 to effect both clos-ing and opening of the control switch isaecolhplished by a `pin |26, se# cured? in position in V'a transverse open-ing in the throttle yshaft :in 'arlyr Suitable way and this pin engages lugs |21 and |28 vprojecting from `block` |23 as the throttle shaft is rotated, to rotate the block |23 in opposite directions. ""ihese lugs may be integral lwitl1` the block Vas shown, or metal pins suitably' secured 1in -`the block.

Formed inthe housing =|I|l is cylinder |36 in which slides ya piston |31 normally held in the position shown in the drawings by a spring |32, so that 'alug |33 projecting from the piston engages the Surface of the' "block "$23. The piston is pref' erably' formed of Bakelite or Similar material but a metal pis'tom-ay loe-used. Retained in position `irl the upper end of cylinder |33 by a suitable clamping ring Y |34 is a sealing washer of copper or other suitablev material, which is engaged vby the end surface |36 of the piston when the latter isniovedhy engine suction against the force of the spring'. En'gagementoi' surface |33 at |31 Atoglrovide ya space in which the retaining ring |34 is received when theoiston engages the' seal washer.

orinally, 'the' contact i2@ is in the position shown in the drawings, lout when the`v Switch `is' closed, such Contact moves to the left until the bent portion thereof, Mt, engages contact |22. When this 'takes place, a toe |4| at the top of contact l2!) `projects through an opening M2 in the Wall of cylinder 133, Ainto a lchannel |43 in the peripheral surface of piston |3i. 'The channel |63 Vis -oi unequal depth vat different parts thereof so "that a shoulder IM isior'med; When the parts are "in the position yshown in the drawings, the piston vmay 'Ino've freely in response to effect of 'engine suction, but 'u'fhen the' switch 94 is closed Jand tl'vi'e `toe |41 extends into channel |42, the upward mov'einem, oi the piston '43| is limited by engagement with tu@ toe 14e.

A suction passage |50 fis `itc-fined i'n 'the upper closed end ci the housing Hi] and the passage |53 may he connected in any suitable way with a'. passage il in the 4wall of Ithe carburetor casting |'|2, which connects through `here |52 'with 'the carburetor outlet passage |53, posterior to the throttle; The forni of the -suction passage is not material, but as illustrated, passage y |51 connects with an vanim-lar channel |511 formed in the wallof a threaded bore |55 Ain the carburetor casting l2. A'reversely'threaded coupling mem-v ber |56 i'nay 'he screwed into the vbore |55 and a similarhore |51 in the housing HB, and an opening les 'in the cou'plir-ig member connects with the channel |54 in any 'position of the coupling membe'rand Ithe-cou'plifng member is also a means to :attach `the 'housing H0 tothe carburetor east-y ing, It will `he understood, however, that 'the suction connection is no part of the present invention and the passage |50 may be connected to the carburetor intake 'by 'any -rneans which is deemed satisfactory.

s, The housing In isi preferably of .die castv metal and is provided with an opening B to admit air in which is positioned a very iine meshed screen` to preventas' far aspossible the admission of dirt.

As` already' indicated, the switch is closed by counterclock'wise rotation oi the block |23 which permit-s the bent portion loo' of contact |20 to move into engagement with contact |22. Opening of the switch is also manual and is effected by' a reverse or clockwise rotation of block |23. When this takes place, a cam shoulder |62 engages the portion Idil of Contact |20 and moves such con-tact to the right so that |4|l rides on the surface |25` as indicated in the drawings. This cam surface is made as abrupt as possible without causing a binding action between such surface and the lpart 14u because it is desirable to close the switch with a snap action and it is important that the cam does not have a gradual enough slope to cause the movement of the switch contact vto closed position to 'be retarded by the grad-ual slope of thel cam.

In the drawings, the parts are shown in the normal position with closed throttle. To close the Switch, the throttle is moved toward open position and the pin |23 moves toward the left until it engages lugr l2? 'before the block |23 is moved, the pressure" of piston |3| and contact |20 preventing movement of the block. Upon engagement of the pin and lug, a very slight additional opening of the throttle moves the block enough to permit movement of the part it into engagement with Contact |22 to close the switch, and the ytinottle may then move on to open position while the switch remains closed. The lug |27 is so 1:1os'i-tio'1f1ed that the throttle maires 'that amount or opening movement found to be inost desirable before engagement of the pin |25 with the lugand movement of Athe block to switch closing position. The throttle can then r'nove on l fur-ther toward open posi-tion,` if necessary, without opening the switch.

When the engine starts, the suction pulls the piston |3| upwardly Auntil shoulder Mt engages toe M and it is stopped in that position until the Switch is `opened manually to disengage the toe from said shoulder. To open the switch, the throttle is -olosedand is moved Itoward closed position Ywithout movi-ng lblock |23 at all until pin |26 engages 'lug |28,y after which continued closing movement of the throttle inoves the parts to the position .showin in the' drawings, opening the switch and permitting the piston to be lifted until surface |36 engages ythe seal washer |35. When the piston is in this position, opening of the u viousl-y described laction of the sealing washer and because of the fact that the toe |4| exerts so much pressure against the side of the piston that it Vwill not vhe overcome by the weight of the piston `and spring |32. The switch, therefore, will not close during operation of the engine under 'its own power.

While the embodiment of the present invention asfherein disclosed constitutes a preferred form, it is 'to he 4kunderstood that `other forms .might be adopted.

What is claimed is as follows:

1. In a starting apparatus for internal combustion engines having a starting motor, a current source and a circuit for connecting said starting motor with the current source; a control switch for controlling said circuit having a switch operating member movable to different positions to effect closing and opening of said switch, manual means for operating said member and operable to move said member to effect either closing or opening of said switch means permitting a predetermined movement of said manual means before said switch operating member is moved, a member movable during self-operation of the engine to a position to prevent closing of said switch, means operative to prevent mcvement of said member to its effective position while said switch is closed, and means operable to release said member to permit operation thereof when said switch closing member is moved to its normal switch opening position.

2. In a starting apparatus for internal combustion engines having a starting motor, a current source and a circuit for connecting said starting motor with the current source; a control switch for controlling said circuit having a switch operating member movable to different positions to effect closing and opening of said switch, manual means for operating said member and operable to move said member to effect either 2" closing or opening of said switch only after a predetermined movement of said manual means, a member movable during self-operation of the engine to a position to prevent closing of said switch, resilient means normally holding said lastnamed member in engagement with said switch operating member to prevent movement of the latter during part of the movement of said manual operating means.

3. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, a member operable by said shaft to effect closing of said control switch, and means permitting a predetermined closing movement of said throttle shaft before said member is moved thereby, a member movable to a position to prevent closing of said switch during self operation of the engine, means for preventing movement of said member while said switch is closed, means for rendering said last-named means ineffective when the switch is opened, and means operable to effect opening of the switch when the throttle is moved to closed position.

4. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, means operable by said shaft only after a predetermined movement thereof to effect clos ing of said control switch, a member movable to a position to prevent closing of said switch during self operation of the engine, means for preventing movement of said member while said switch is closed, means for rendering said lastnamed means ineffective when the switch is opened, means operable to effect opening of the switch when the throttle is moved to closed position, and resilient means holding said member in engagement with the means operable -by the throttle shaft to close the switch, so as to oppose movement of said means by the said throttle shaft.

5. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, means operable by said shaft only after a predetermined movement thereof to effect closing of said control switch, a member movable to a position to prevent closing of said switch during self operation of the engine, means for preventing movement of said member while said switch is closed, means for rendering said last-named means ineffective when the Switch is opened, means operable to effect opening of the switch when the throttle is moved to closed position, resilient means holding said member in engagement with the means operable by the throttle shaft to close the switch, so as to oppose movement of said means by the said throttle shaft, and means whereby engine suction moves said member to a position to render said resilient means ineffective when the engine is operating under its own power.

6. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when cosed to cause the starting motor to be connested with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, means movable by said shaft as the throttle is opened to effect closing of said control switch and movable by said shaft as the throttle is closed to effect opening of the control switch, an operating connection between the throttle shaft and said movable means including a lost motion device whereby said means is effective to close the switch only after throttle has made a predetermined opening movement, and means yieldingly opposing movement of said movable means by the throttle shaft.

7. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, a switch operating member rotatably supported by said throttle shaft, means effective after a predetermined opening movement of the throttle to connect the said member to said throttle shaft for rotation therewith so as to effect closing of the switch after the throttle has made a predetermined opening movement, a member normally engaging the sur face of said switch operating member and acting as a brake to oppose movement of said member with the throttle shaft, and spring means exerting a predetermined pressure on said member.

8. In a starting apparatus for internal cor-:rbustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, a switch operating member rotatably supported by said throttle shaft, means effective after a predetermined opening movement of the throttle to connect the said member to said throttle shaft for rotation therewith so as to effect closing of the switch after the throttle has made a predetermined opening movement, a suction operated member movable to a position to prevent closing of said switch when the engine is operating under its own power, and resilient means normally holding last-named member in engagement with said switch operating member to oppose movement of the switch operating member by the throttle shaft.

9. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, a switch operating member rotatably mounted on the throttle shaft and having a lug projecting therefrom, and an operating member projecting from the throttle shaft and adapted to engage said` lug and move the switch operating member to a position to close the switch after the throttle has made a predetermined opening movement.

10. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, a switch operating member rotatably mounted on the throttle shaft and having a lug projecting therefrom, an operating member projecting from the throttle shaft and adapted to engage said lug and move the switch operating member to a position to close the switch after the throttle has made a predetermined opening movement, and resiliently operated means normally engaging said switch operating member and effective to hold said member against movement before engagement of said lug by the operating member.

11. In a starting apparatus for internal combustion engines having a starting motor, a current source, a control switch effective when closed to cause the starting motor to be connected with said current source and when opened to interrupt such connection, a carburetor throttle valve for controlling the amount of combustible mixture supplied to the engine and an operating shaft therefor, a switch operating member rotatably mounted on the throttle shaft and having a pair of spaced lugs projecting therefrom, an operating member extending from the throttle shaft to a position between said lugs, said member being operable to engage one of said lugs and move the switch operating member to switch closing position only after the predetermined opening movement of the throttle and operable to engage the other lug only after a predetermined closing movement of the throttle from an open position.

12. In a starting apparatus for internal combustion engines having a starting motor, a current source and a circuit for connecting said starting motor with the current source, a control switch for controlling the opening and closing of said circuit and including a plurality of contacts and. a switch operating member movable to different positions to effect closing and opening of said switch, manually operated means for actuating said member and effective to move said member to either switch closing or switch opening position, a cylinder having an opening therein through which a part of one of said switch contacts projects when the switch is closed, means for communicating the engine suction to said cylinder, a piston slidable in said cylinder and movable by engine suction when the engine is self-operative to a position where a surface on said piston is engaged by that part of said contact which extends through the cylinder opening and movement 0f the contact to switch closing position is prevented.

13. In a starting apparatus for internal combustion engines having a starting motor, a current source and a circuit for connecting said starting motor with the current source, a control switch for controlling the opening and closing of said circuit and including a plurality of contacts and a switch operating member movable to different positions to effect closing and opening of said switch, manually operated means for actuating said member and eifective to move said member to either switch closing or switch opening position, a cylinder to which the engine suction is communicated and having a sealing washer positioned at one end of said cylinder, a piston slidable in said cylinder and movable by engine suction when the engine is self-operative, to a position where closing of the switch is prevented by the piston and in which one end of the piston engages the sealing washer, whereby the piston is held in position to prevent closing of the switch by a force less than that required to move it to such position.

LAWRENCE C. DERMOND.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Re. 22,385 Coffey Oct. 26, 1943 1,248,870 Kane Dec. 4, 1917 1,635,078 Gilbert July 5, 1927 1,788,713 Good et al. Jan. 13, 1931 1,862,006 Collins June 7, 1932 1,974,208 Ferguson Sept. 18, 1934 2,021,502 Ferguson Nov. 19, 1935 2,105,643 Dyer Jan. 18, 1938 2,326,125 Dermond Aug. l0, 1943 2,356,064 Jorgensen et al. Aug. 15, 1944 2,399,542 Collins Apr. 30, 1946 2,492,340 Winkler Dec. 27, 1949

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