US2132615A - Phonograph stop - Google Patents

Description

Oct. 11, 1938. E. c. GUEDON PHONOGRAPH STOP Filed July 30, 1936 4 Sheets-Sheet l Oct. 11, 1938. E. c. GUEDON PHONOGRAPH STOP Filed July 50, 1936 4 Sheets-Sheet 2 Oct. 11, 1938. E. c. GUEDO N PHONOGRAPH STOP Filed July 30, 1936 4 Sheets-Sheet 3 Oct. 11, 1938. E. c. GUEDON PHONOGRAPH STOP Filed July 30, 1936 4 Sheets-Sheet 4 Patented Oct. 11, 1938 UNITED STATES 2,132,615 PHONOGRAPH 's'ror Emile C. Guedon, Audubon, N. J., assignor to Radio Corporation of America, a corporation of Delaware Application July 30, i936, Serial No. 93,378

16 Claims.

This invention relates to phonographs, and more particularly to an automatic starting and stopping device therefor.

The principal object of my invention is to provide improved control mechanism for electrically operated phonographs which will automatically render the phonograph inactive upon completion of playing of a record having any type of conventional terminal. groove, and which will automatically render the phonograph active for playing of a record by a mere slight manipulation of the pick-up arm prior to placing it upon the record.

More specifically, it is an object of my invention to provide an improved stop mechanism for electrically driven phonographs which will automatically shut off the power to the driving motor at the completion of playing of a record and which will, at the same time, positively stop rotation of the turntable.

Another object of my invention is to provide an improved stop mechanism for phonographs which will effectively hold the turntable against rotation when the playing of a record has been completed irrespective of the type of motor employed for driving the turntable.

In certain types of electrically driven phonographs, it has been found expedient to use a synchronous motor which is non-self-starting and which, therefore, must be given a starting impulse. It is a further object of my invention to provide, in phonographs of this type, improved means for automatically imparting to the motor a starting impulse.

Another object of my invention is to provide improved mechanism as aforesaid which will permit repetition of portions of a record within predetermined limits without becoming operative to stop the phonograph;

Still another and important object of my invention is to provide an improved automatic starting and stopping device as aforesaid which is extremely simple in construction and inexpensive in cost, so as to be suitable for low-priced phonographs, but which is, nevertheless, highly efiicient in operation.

According to my invention, the starting device and the stopping device are both controlled by the tone arm or pick-up arm of the phonograph. The starting mechanism consists of a normally inoperative auxiliary motor which is of the self starting type and which is pivotally mounted adjacent the turntable with its armature shaft extending in close proximity to the turntable periphery, butnormally out of engagement therewith. When a record on the turntable is to be played, the pick-up arm is moved away from the record slightly, whereupon the auxiliary motor is energized and it is tipped on its pivotal axis sufficiently to bring afriction wheel on its armature shaft into engagement with the turntable periphery. This imparts a starting impulse to the synchronous driving motor, the circuit of which has meanwhile been completed, whereby the driving motor continues to run. As the pick-up arm is thereafter returned and placed on the record, it opens the auxiliary motor circuit and permits it to move away from the turntable to its normal, inactive position.

The stopping mechanism comprises a lever which is frictionally actuated by the pick-up arm as the latter moves across the record in the spiral sound groove thereof and which, in turn, gradually advances a plunger into the path of a cam fixed to the rotor of the driving motor. The cam is so formed that it forces the plunger and the aforesaid lever back to their initial position as long as the pick-up arm moves across the record at the relatively slow speed determined by the adjacent turns of the sound groove. When, however, the needle reaches the coarse-pitched lead-in groove which connects the sound and terminal grooves, the pick-up arm is given a quick impulse toward the record center, which causes the aforementioned lever to move rapidly to interpose the end of the plunger in the path of the cam head. Thus, upon the next turn of the rotor, the cam strikes the plunger squarely to cause it to effect opening of the driving motor circuit and substantially simultaneously to bring a friction brake into engagement with the turntable which is now merely coasting. The parts are so arranged that removal of the pick-up arm to its original position will automatically reset the mechanism for operation in connection with the next record.

The novel features that I consider characteristic of my invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, as well as additional objects and advantages thereof, will best be understood from the following description of several embodiments thereof when taken in connection with the acthe parts at about the time the driving motor is started,

Figure 2 is a view thereof partly in elevation and partly in section,

Figure 3 is an enlarged sectional view taken on the line III-III of Fig. 1,

Figure 4 is a plan view similar to Fig. 1 but showing the positionof the parts at the beginning of playing of a record,

Figure 5 is a similar View showing, in solid lines, the position of the parts just before the stop mechanism has been tripped into operation, and, in dotted lines, the position of the parts just after the stop mechanism has been tripped,

Figure 6 is a detail View of the turntable braking element,

Figure 7 is an enlarged fragmentary elevation showing the relation between the pick-up arm, the friction lever, the switch lever and the brake lever,

Figure 8 is a view similar to Fig. 1, but showing a modified form of my invention, and V Figure 9 is an enlarged view thereof partly in section and partly in elevation taken approximately on the line IXIX of Fig. 8.

Referring more specifically to the drawings,

wherein similar reference characters designate corresponding parts throughout, there is shown,

in Figs. 1 to 5, a motor board I on which is' mounted an electric driving motor 3 of the nonself-starting type, the motor being, preferably, a synchronous motor of the type disclosed and claimed in the copending application of Henry E. Boys, Serial No. 8,664, assigned to the Radio Corporation of America, and including a stator 5 surrounded by an annular rotor 1. Fixed to n the rotor 'I is a turntable 9 upon which a record II is supported during reproduction, the turntable 9 including a peripheral flange I3 and a record centering spindle I5.

A bushing I6 is fixed to the motor board I and carries a hollow post H which supports a scanning member I9 for movement over the turntable 9 in well known manner, the scanning member I9 comprising a supporting arm 2| for a pick-up device 23, the needle 25 of which is adapted to track the sound groove of the record II. The post I! extends through the motor board I and has a lever 21 fixed to its lower end, whereby, as the scanning member I9 moves relative to the record, the lever 2'! moves with it and in the same direction.

To the motor board is also fixed a, plate 29 which pivotally carries a suitable electric motor 3| of the self-starting type, the motor 3| having its armature shaft 33 extending upwardly through an opening 34 in the motor board and terminating adjacent the turntable flange I3, as clearly shown in Fig. 2. The plate 29 also pivotally carries a substantially L-shaped lever 35, the longer arm 35a. of which has a downwardly extending pin 31 and an upwardly extending pin 39 thereon, and the shorter arm 35b of which bears against the armature shaft 33. A coil spring 4| having one end fixed to the frame of the motor 3| and its other end fixed to the pin 3'! constantly urges the lever arm 35b against the armature shaft 33, the tension on the spring 4| being such that, when the lever 35 is moved away from the motor 3|, it will cause the motor to pivotally follow the arm 35b until a friction wheel 43 on the armature shaft 33 engages the peripheral flange I3 of the turntable 9 whereupon, if the motor 3| is energized, the rotating friction wheel 43 will rotate the turntable 9 and thus impart a starting impulse to the rotor I.

The arm 21a of the lever 21 has a downwardly extending pin 45 thereon which is adapted to engage the toe 350 of the lever 35 when the scanning member I9 is moved away from the turntable 9, the pin 45,, in turn, moving the lever 35 away from the motor 3|. When this movement takes place, the pin 39 of the lever 35, which is received in the forked end of the movable member 41 of a switch 49 in series with the motor 3|, moves the member 47 to close the circuit to the motor 3|. It will thus be evident that, by merely moving the scanning member I9 away from the turntable 9 a sufficient distance, the pin 45 will move the lever 35 to bring the friction wheel 43 into contact'with the flange I3 and to complete the circuit to the motor 3| immediately thereafter. Upon return of the scanning member |9 toward the turntable, the spring 3| pulls the lever 35 back, causing the pin 39 to open the switch 49 again and also causing the lever arm 35b to force the armature shaft 33 away from the flange I3 by pivoting the motor 3| back to itsrest position.

Also fixed to the motor board I is a second plate 5| which carries the control mechanism'for automatically stopping the phonograph upon completion of playing of each record. The plate 5| has staked or otherwise suitably secured thereto a downwardly extending stud 53 on which is rotatably carried a sleeve 55 staked at its lower end to a yoke member 51. A friction lever 59 is loosely mounted on the sleeve 55 between a pair of washers BI and 63, the latter of which bears against a C-washer 65 on the sleeve 55. Interposed between the yoke 51 and the washer BI and surrounding the sleeve 55 is a compression spring 61 which forces the washer 6|, the lever 59 and the washer 63 with sufficient force against the washer 65 to provide a frictional coupling between the lever 59 and the sleeve 55. Thus, although the frictlon lever 59 is rotatable on the sleeve 55, it will move as a unit therewith and with the yoke 5'! in the absence of a restraining force. The pin 45 on the lever arm 21a extends downwardly between the side arms 51a and 51b of the yoke 51, and, when the scanning member I9 is moved across the record II, the pin 45 engages the arm 571) and imparts counter-clockwise rotation to the yoke 51 (as viewed in Figs.

' 1, 4 and 5) which, in turn, imparts similar rotation to the friction lever 59 through the friction coupling previously described. This friction coupling can be arranged to impose no undue load on the scanning member I9 and still serve effectively for the purpose set forth by choosing a coil spring 61 of suitable strength.

Pivotally mounted on the plate 5| is a trip lever 69 having a pair of downwardly extending, aligned, apertured lugs II which serve as bearings for a plunger rod 13. One end of the rod I3 has a fiber or other suitable cap thereon, while the other end thereof is reduced and is loosely received in the forked end 59a of the friction lever 59 whereby, as the lever 59 is moved counterclockwise in the manner heretofore described, the rod 13 is advanced in the bearing members H to bring the plunger cap 15 into the path of movement of an actuating cam I1 on the rotor l. The

trip lever 69 also has an arm 69a extending therefrom a distance suflicient to engage a pin 19 on the movable element of a switch 8| in series with the driving motor 3, as well as a shoulder 69b for a purpose presently to be set forth.

lever '2 I.

Fig. 5. from the turntable 9 whereupon the lever exextension 83d which passes through an opening 85in the motor board I .and carries, at its upper end, a brake pad 81 adapted to engage the turntable peripheral flange I3. The pad 81 is held in a cup 89 (Fig. 6) formed on a screw 9| which is threadedly received in the extension 83d, whereby the pad 8! may be adjusted for wear relative to theflange I3, a nut 93 holding the screw 9| in adjusted position. A coil spring 95 fixed-at one end to a downwardly extending lug 91 on the plate 5| and at the other end to a similar lug 99-on the lever arm 83a constantly urges the brake pad into position to engage the flange I3 for holding the turntable 9 against rotation. However, the brake lever 83 is normally held out of turntable engaging position by engagement of the shoulder 691) with the reduced end of the lever arm 83a, as clearly shown in Fig. 4, a second'coil spring |I having one end fixed to the lug 91 and the other end fixed to one of the lugs 'II constantly biasing the lever 69 into the position shown in Fig. 4. At the same time, by engaging the arm 83a, the trip lever 69 is limited in itsclockwise movement (Figs; 1, 2 and 4) under the influence of the spring I0I.

The arm 83?) of the lever 83 is provided with a downwardly extending pin I93 adapted to be engaged by a laterally extending arm 2111' on the When the scanning member I9 is moved away from the turntable 9, as previously described, the arm 21b engages the pin I93 and rotates-the lever 83 in a clockwise direction (Figs. 1,4 and 5) against the action of the spring 95 to remove the brake pad 81 from engagement with the turntable flange I3. At the same time, the curved extension 21c of the lever 21 engages the pin "I9 and closes the switch 8| whereby the driving motor 3 is energized preparatory to bringing the friction wheel 43 into engagement with the flange I3.

In tracing the operation of the mechanism, let it be assumed that the parts are in rest position, with the needle 25 resting on a rubber or other suitable support I05, and with the switch BI open and the brake pad 8! in engagement with the turntable flange I3, as shown in dotted lines in The pick-up arm 2| is first moved away tension 210, by engagement with the pin I9, closes the driving motor switch 8|, and the lever arm 2Tb, by engagement with the pin I03, removes the brake pad 81 from engagement with the turntable periphery I3, the pin 45 having been brought meanwhile into engagement with the toe armature shaft 33 is rotating, a starting impulse is imparted to the rotor I of the driving motor 3 and the turntable 9 with its record II will continue to rotate. The pick-up arm 2| is then moved back to the turntable and the needle 25 is placed in the starting groove of the record,

the spring 4| returning the lever 35 and the motor3| to initial position and causing the switch 49 to be opened.

I During the operation just described, the pin 45; by engaging the yoke arm 51a, moves the yoke 57 and the friction lever 59 to the position shownin Fig. l, and when the pick-up arm 2| is moved back to the record II and the needle 25 placed thereon, the pin 45 occupies the position between the yoke arms 51a and 51b shown in Fig. 4. As the sound groove of the record advances the pick-up arm 2|, the pin 45 gradually approaches and eventually engages the yoke arm 51b, thereafter imparting counter-clockwise rotation to the yoke 51 and the friction lever 59 (as seen in Fig. 4) and gradually advancing the plunger head or cap I5 into the path of the cam TI. The cam edge 11a of the cam 11 is so formed that, as long as the plunger 13 is advanced a distance corresponding to the distance which the pick-up arm is advanced by adjacent turns of the record sound groove, theleading end portion of the cam edge Ila will just slip by the end of the plunger head 75 and the rise on the edge IIa which follows will force the plunger 13 and the friction lever 59 back the distance they were advanced during the preceding revolution. This is made possible by reason of the friction coupling between the lever 59 and the yoke 51.

When reproduction of the record has been completed, at which time the pick-up arm occupies the position designated by its center line A 'in Fig. 5, the coarse-pitched spiral lead-in groove IIl'I passes under the needle 25 and quickly moves the pick-up arm 2| to the position represented by its center line B in Fig. 5. The resulting effect on the plunger 13 is to move it faster and further into the path of the cam 11 so that, upon the next revolution of the rotor I, the cam edge 11?) strikes the plunger head 15 and imparts to it and to the trip lever 69 counter-clockwise movement (as seen in Fig. 5) against the action of the spring IOI. Thereupon, the arm 69a opens the switch 8| and moves past the pin I9 after which the spring Illl returns the trip lever 69 to its normal position. At the same time, since the shoulder 6922 has been removed from the end of the arm 83a, the spring 95 moves the brake lever 83 counter-clockwise about its pivot to bring the friction pad or brake 81 into engagement with the turntable flange I3 to positively hold the turntable 9 against rotation. The pick-up arm may then be returnedto rest position with the needle 25 on the support I05, at which point the operating cycle was commenced.

The modification of my invention thus far described includes the starting motor 3| for autor matically starting the driving motor 3. In certain cases, it may be preferable to employ a phonograph wherein the starting motor 3| is omitted, so that a starting impulse must be imparted to the driving motor 3 by hand. The 'modification of my invention shown in Figs. '7 to 9 is provided to fill the requirements of such cases.

In this modification, the structure of the automatic stopping mechanism is almost identical with that previously described in connection with Figs. 1 to '7. In place of the lever 21, however, 'I provide a manually operable lever I09 which is fixed to the pivot post IT for rotation therewith in a manner similar to the lever 21. The lever I09 is provided with an upwardly directed extension III which passes through an opening H3 in the motorboard I and through a slot in an index plate I I5, being provided with a handle portion I I! which may be easily gripped between the fingers for manipulation of the lever I99. The index plate may be marked with the designations on and off with reference to the motor switch 8! to indicate that, when the lever I09 is moved manually to the on position, the

motor 3 is energized, and when it is moved to the off position, the switch 8I is open and the motor 3 deenergized.

The lever I09 is provided with an arm I091) which corresponds to the lever arm ZIb and 00- operates with the downwardly extending pin I93 of the brake lever 83 in the manner previously described in connection with Figs. 1 to '7. The lever I09 is also provided with a curved extension I090 which corresponds to the curved extension 270 of the lever 21, being forkedat its extreme end to receive the pin I9 of the switch 8 I.

Also fixed to the pivot post I! is a short lever II9 corresponding to the lever arm 21a and carrying the downwardly extending pin 45. The lever IIS moves in unison with the pick-up arm 2! and its pin 45 acts upon the yoke 51 in exactly the same manner as in the previously described modification of my invention.

' When it is desired to operate the form of my invention disclosed in Figs. 8 and 9, the lever I09 is moved to the on position, as shown in Fig. 8, whereupon theswitch BI is closed and the motor 3 is energized. The record is then played and the trip lever 69 is eventually tripped by the cam 11 in the manner heretofore described. Thereupon, the lever arm 69a opens the switch 8] and forces the lever I 89 back to the off position, and, since this'removes the lever arm I091) from engagement with the pin I03, the spring 95 rotates the brake lever 83 counter-clockwise (as seen in Fig. 7) to bring the brake pad 87 into engagement with the turntable flange I3. However, when the lever I IE9 is returned to on position, its arm I091) again engages the pin I63 and forces the brake lever 83 to rotate in a clockwise direction to remove the brake pad 8! from engagement with the turntable flange I3. The switch 8| is preferably of the toggle type and is provided with a spring (not shown) which operates in well known manner to retain the movable switch element carrying the pin 79 to one or the other side of its pivotal axis, and this spring may be relied upon to hold the lever I09 in on position against the action of the spring 95.

It will be noted that, in the modification of the invention now under consideration, the lever arm 83a is shorter than the corresponding lever arm of the construction of Figs. 1 to '7, and that it does not engage the shoulder 69b of the trip lever 69, In the earlier described modification, the reduced end of the lever arm 83a is relied upon to prevent rotation of the trip lever 69 to a point where the plunger head "I will fail to be interposed in the path of the cam II as the plunger 73 is gradually advanced. In the modification of the invention shown in Figs. 8 and 9, however, this function is performed by a pin I2I fixed to the plate 5I.

With either modification of my invention, should the plunger head or cap 15 be advanced into the path of the cam TI and the turntable 9 rotated backwards (i. e., counter-clockwise, as seen in Figs. 1 and 8), the rear edge 17d of the cam II will strike the plunger head I5 and possibly damage the parts, particularly if this practice is carelessly continued. To eliminate this possibility, I preferably sharply taper off the rear edge portion 'I'Icof the cam edge 'I'Ia. With'this construction, if the turntable 9 is rotated in the wrong direction, the sharply tapered cam edge He will merely force the plunger rod .13 back through its bearings II and the automatic stop mechanism will not be damaged.

From the foregoing description of two modifica'tionsiof my invention, it will be apparent to those skilled in the art" that my improved start and stop "mechanism has a number of advantages over those previously known. For example, it is possible, with my present invention, to repeat any portion of therecord that may be covered by the pickup device within the limits of movement of the pick-up arm 2I determined by the yoke arms 51a and 57b, and the pin 45. Movement of the pick-up arm within these limits will have no eifect whatsoever upon the yoke 51 and its associated friction lever 59.

It will also be apparent to those skilled in the art that, although I have-shown and described but two modifications of my invention, many other modifications thereof and changes therein are possible. I desire, therefore, that my invention shall not be limited except insofar as is made necessary by the prior art and bythe spirit of the appended claims.

I claim as my invention:

1. In a phonograph of the type having a nonself-starting motor, a member movable relative to a record in playing position on the phonograph, means responsive to movement of said member in one direction for imparting a starting impulse to said motor, andmeans responsive to movement of said member in another direction for stopping said motor. I

2. In a phonograph of the type having a nonself-starting motor, a member movable relative to a record in playing position on the phonograph, means associated with said member and responsive to movement thereof at least a predetermined distance in one direction for imparting a starting impulse to said motor, and means responsive to movement of said member in another direction for stopping said motor.

3. In a phonograph, the combination of a driving motor, of the non-self-starting type which includes a rotor, a normally inactive auxiliary motor of the self-starting type associated with said rotor, a member movable relative to a record in playing position on the phonograph, and coupling means between said member and said auxiliary motor adapted to energize said auxiliary motor and cause it to impart a starting impulse to said rotor upon movement of said member to a predetermined position.

4. The invention set forth in claim 3 characterized in that said rotor has a record supporting turntable 'mounted thereon, characterized further in that said auxiliary motor is mounted adjacent said turntable for movement toward and away from said turntable, and characterized still further by the addition of means constantly urging said auxiliary motor away from said turntable, said coupling means acting to bring said auxiliary motor into engagement with said turntable upon movement of said member to said predetermined position.

5. The invention set forth in claim 3 charac terized in that said rotor has a record supporting turntable mounted thereon, characterized further in that said auxiliary motor is an electric motor and has a friction wheel on its armature shaft, said auxiliary motor being mounted adjacent said turntable periphery for pivotal movement relative thereto, and characterized still further by the addition of means'constantly urging said auxiliary motor away from said turntable, said coupling means acting to bring said friction wheel into engagement with the turntable periphery to impart a starting impulse to said rotor upon movement of said member to said predetermined position.

6. In a phonograph, the combination of a motor including a rotor, an actuating element on said rotor, a turntable carried by said rotor and adapted to support a record for playing, a rec 0rd scanning member movable relative to said record, and means associated with said scanning member arranged to be actuated by said actuating element upon a variation in movement of said I scanning member relative to said record for stopping rotation of said rotor.

'7. In a phonograph, the combination of an electric motor including a rotor, an actuating element on said rotor, a turntable carried by said rotor and adapted to support a record for playing, a record scanning member movable across said recordat a predetermined speed when scanning the record, and means associated with said scanning member for controlling the motor, said control means being movable by said scanning member a predetermined distance toward the path ,of'movement of said actuating element during each revolution of the rotor while said record is being scanned, and said actuating element and control means being so constructed and arranged that, as long as said scanning member traverses the record at the scanning speed, said control means is insuificently advanced to be actuated by said actuating means to stop the motor, but when said scanning member traverses the record at a substantially greater speed, said control means is advanced sufficiently to be actuated by said actuating means to stop rotation of said rotor.

8. The invention set forth in claim '7 characterized in that said control means is frictionally associated with said scanning member whereby it is movable relative to said scanning member, and characterized further in that said actuating element is adapted, during each revolution of the rotor, to return said control means the distance it is advanced by said scanning member so long as said scanning member traverses the record at the scanning speed.

9. The invention set forth in claim '7 characterized in that said control means includes a lever which is frictionally associated with said scanning member whereby it is movable relative to I slidable member that, during each revolution of the rotor, said cam returns said slidable member the normal distance it is advanced in response to movement of said scanning member at said scanning speed, but when said scanning member moves over the record at a greater speedwhereby said slidable member is advanced a greater than normal distance relative to said cam, said cam engages said slidable member to effect stopping of the motor.

10. The invention set forth in claim '7 characterized in that said control means includes a pair I of frictionally coupled, relatively movable elements, and characterized further in that said scanning member is arranged to be movable with respect to one of said elements within predetermined limits without moving said last named element whereby portions of the record may be repeated without affecting operation of said motor.

11. The invention set forth in claim 7 characterized by the addition of a switch in the circuit of said motor, and characterized further in that said control means is arranged to open said switch upon being actuated by said actuating element.

12. The invention set forth in claim 7 characterized by the addition of a brake device arranged to engage said turntable but normally.out of engagement therewith, and characterized further in that said control means is arranged to eflect engagement of said turntable by said brake device upon being actuated by said actuating element.

13. The invention set forth in claim '7 characterized by the addition of a switch in the circuit of said motor and by the addition of a brake device arranged to engage said turntable but normally out of engagement therewith, and characterized further in that said control means is arranged to open said switch and to efiect engagement of said turntable by said brake device upon being actuated by said actuating element.

14. In a phonograph, the combination of a motor, a turntable arranged to be driven thereby and adapted to support a record for playing, a record scanning member associated with said turntable, a switch in the circuit of said motor, a brake device arranged to engage said turntable, manually operable means for closing said switch and removing said brake device from engagement with said turntable whereby said motor is adapted to drive said turntable, and means controlled by said scanning member for automatically opening said switch and effecting engagement of said brake device with said turntable and for resetting said manually operable means to initial position.

15. In a phonograph, the combination of a motor, a turntable arranged to be driven thereby and adapted to support a record for playing, a record scanning member associated with said turntable, a switchin the circuit of said motor, a brake device arranged to engage said turntable, manually operable means for closing said switch and removing said brake device from engagement with said turntable whereby said motor is adapted to drive said turntable, means controlled by said scanning member for automatically opening said switch and eifecting engagement of said brake device with said turntable and for resetting said manually operable means to initial position, and means carried by said motor for actuating said last named means to efiect the opening of said switch, the engagement of said braking device with said turntable, and the resetting of said manually operable means.

16. In a phonograph of the type having a nonself-starting motor, a member movable relative to a record in playing position on the phonograph, means responsive to movement of said member for imparting a starting impulse to said motor, and means also responsive to movement of said member for stopping said motor.

EMILE C. GUEDON.

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