US1385407A - Automatic stop mechanism for talking-machines - Google Patents

Description

H. L. TUNISON. AUTOMATIC STOP MECHANISM FOR TALKING MACHINES.

APPLICATION FILED JUNE 17, 1919. 1,385,407. Patented July 26, 1921.

2 SHEETS-SHEET I.

"Mill llllll A %1; 14 autumn H. L. TUNISON.

AUTOMATIC STOP MECHANISM ron TALKING MACHINES. APPLICATION FILED JUNE 17, I919.

Patented July 26, 1921.

2 SHEETS-SHEET 2- UNITED STATES PATENT OFFICE."

HAROLD L. TUNISO'N, OF UPPER MONTCLAIR, NEW JERSEY, ASSIGNOR TO FRANK L.

DYER, OF MONTCLAIR, NEW JERSEY.

AUTOMATIC STOP MECHANISM FOR TALKING-MACHINES.

Application filed June 17,

To all whom it may concern Be it known that I, HAROLD L. TUmsoN, a citizen of the United States, residing at Upper Montclair, in the county of Essex, State of New Jersey, and have a post-ofiice address at No. 219 Alexander avenue, Upper Montclair, N. J have invented certain new and useful Improvements in Automatic Stop Mechanism for Talking-Machines, of which the following is a specification.

My invention relates to certain new and useful improvements in automatic stop mechanisms for talking machines, of the type in which the operation of the mechanism is controlled by the position of the tone arm which has a generally diametric movement with respect to the record disk.

M improved automatic stop mechanism is adapted to be assembled as a part of any talking machine having a tone arm or other element partaking of a relatively transverse movement with respect to the record. Since the device is extremal simple and compact, it may also be manu actured and sold as a separate attachment capable of being applied to existing types of talking machines.

My improvements are essentially mechanical and comprise a friction brake which, when released, will engage and prevent rotation of the turn table or other record car rier, said brake being locked in a withdrawn osition during the playing of the record, ut being tripped or released when the tone arm or other controlling element has reached a predetermined point transversely of the record.

Automatic stop devices of this type, both electrical as well as mechanical, are of course, well known. Such stop devices, as heretofore suggested, have been adjustable to accommodate records of difierentlength; or in other words, have been arranged to operate or trip the brake mechanism at the desired point of the transverse travel of the tone arm regardless of the len th of the record. In the case of an elect'rlcal device, it is not difiicult to set the stylus in the last groove of the record and to therefrom determine when the brake device shall be electrically tripped, whereby when the tone arm reaches a point corresponding with the last groove, a circuit will be closed to thus release the brake and arrest the rotation of the turn table or other record carrier. Electr cal devices, while thus su ficiently accu- Specification of Letters Patent.

Patented July 26, 1921.

1919. Serial No. 304,754.

rate, are relatively complicated, likely to get out of order, more or less clumsy in appearance, and, of course, they fail to work if any derangement occurs in the electrical circuit or in the battery or in the contacts.

Automatic stop mechanism, as heretofore suggested, of the mechanical type, have been slmple 1n construction, compact in appearance and rugged in operation, but they have lacked accuracy of adjustment. With some mechanical stops the brake has been locked in a withdrawn position by various arrangements of triggers which are adapted to be released by the movement of the tone arm or other element as the same approaches the point relative to the record where the turn table or other record carrier is to be arrested. With the rior mechanical devices with which I am amiliar, the arrangement is such that the adjustment point is that at which the tone arm engages the tripping mechanism, and therefore there is necessarily a further movement of the tone arm before the actual tripping takes place. Obviously the adjustment is very delicate because the lateral travel of the stylus is of the order of one one-hundredth of an inch for each rotation of the record, and this lateral travel is, of course, proportionally diminished if the tone arm engages the brake trip at a point intermediate of its pivot and its free end. With these prior mechanical devices, the attempt has been made to so make the adjustment that the brake will be actuated at the instant corresponding with the last roove of the record. This, however, is pure y a matter of guess; ordinarily the operator engages the stylus three or four grooves short of the last groove and sets the release mechanism to correspond with the point thus selected; then, as the tone arm nears the completion of the record at the point selected, it will commence to operate the trigger, the expectation being when the record has been completely played and the stylus is in the last groove the brake will be released so as to arrest rotation of the turn table. Obviously this human factor is unreliable; if the mechanism is set to operate too far in from the last groove, the brake will be released and the turn table stopped before the record has been completely played; on the other hand, if not set far enough in from the last groove, the brake mechanism is liable not to operate at all.

' ustment is reached and Furthermore, it is a diflicult matter, even at best, to select the proper groove where the adjustment is to be made owing to the minute size of the grooves.

So far as I am aware, no one has hereto foresuggested a mechanical device by which the brake mechanism may be set to operate with the stylus in the last groove of the record and will operate with certainty and accuracy when the stylus has reached the point at which the adjustment was made. Thisresult I accomplish with my present im- :.provements. To this "end, I have designed an improved brake mechanism in which when the'l stylus'i's engaged with the last groove of the record (or, of course, any other point where the record is to be stopped) and the gb'rake mechanism is adjusted with re- (spect to the tone arm at that indentical point, the adjustment will correspond to the tripping-point of the trigger, or, in other words, willcorrespond to the exact instant where the brake will be released. Having thus determined the tripping point of the brake releasing mechanism, I so coordinate the parts thatwhe'nthe tone arm is moved to the commencement of the record the trigger will be moved a'utomatically into position to receive the brake mechanism and hold it in a withdrawnposition. Thereupon, as the tone arm progresses transversely across the face of'the record, and as it nears the end of the record, it eommences 'to gradually operate the trigger, which will be finally released at the instant corresponding to the precise pointof original adjustment. This capacity ofmyimproved mechanism of automatically bringing-the trigger into operative position to engage the brake mechanism provides a v'ery'accurate mechanical determination of the movement which thetone arm shall have in tripping the releasing mechanism; or, in other words, I determine mechanically and automatically the extent to which the tone arm shall move in releasing the trigger, whereas, with devices as heretofore proposed, this determination has been a matter of guess work on the part of the operator who engages the stylus a sufiicient distance in ward from the end of therecord to provide for the tripping ofthe trigger, as I have explained. The essential distinction between my-improved stop mechanism is that the poin't'of adjustment or determination corres ends to the tripping point of thetrigger, 'WlllCll after its adjustment is automatically brought into position to engage and withhold the brake, and thetone arm engages the "tripping mechanism before the point of ad gradually with draws the trigger which releases the brake at thepointiof adjustment. With prior devices, the ipoint'of adjustment has been that point where the tone arm engages the trip andcommences to release the trigger, so that the further movement of the tone arm after passing the point of adjustment acts to release the trigger, which therefore frees the brake at a point that the operator has to guess at as a matter of experience. This general idea of providing for the positioning ofmechanism at a point corresponding to the final release of the trigger, and the automatic movement of the trigger thereafter into position to lock the brake withdrawn, may be carried out by a variety of mechanical devices all involving the same inventive thought.

lVith the preferred embodiment of the invention, I make use of a brake device having a trigger pin arranged to lock the brake in a withdrawn position, said brake being spring actuated, whereby when the trigger pin is tripped the brake will be released to engage and arrest rotation of the turn table or other record carrier. I provide a trip ping lever which is adapted to engage and trip the trigger pin when the tone arm has been moved to the predetermined point, and with the preferred form of the device I also use a determining arm to which the tripping lever is pivoted, whereby when the tripping lever and determining arm are simultaneously engaged with the tone arm in its i'iual position corresponding to the last groove of the record, the trigger pin will be in the position where it will release the brake. By frictional means the determining arm will remain in the position of its adjustment thus corresponding to the releasing point of the brake, but the tripping lever being capable of independent movement with respect to the determining arm, when the tone arm is moved to the beginning of the record, will be moved relatively to the determining arm so as to bring the trigger pin in position to en gage and lock the brake in its withdrawn position. As the tone arm nears the end oi its movement, it will come in contact with the tripping lever and gradually move the same pivotally with respect to the determining arm, and when these two arms are thus brought into line the trigger pin will be released to thus trip the brake. In other words, the distance the tripping lever moves with respect to the determining arm is an exact distance determined automatically by the very engagement of the tripping lever and determining arm simultaneously with the tone arm in its final position.

It is not necessary to use a separate tripping lever and determining arm as explained, since it is possible to use only a single arm performing the functions of the two. lVhen such a single arm is used it is first brought into engagement with the tone arm to determine the tripping point, and then when the tone arm is moved to begin playing the record, the combined tripping and determining arm partakes of an inde pendent auxiliary movement, as a result of which the trigger in is moved into position to lock the bra e.

Both forms of the invention are illustrated in the accompanying drawings formin part of. this specificati0n,'and in which, igure 1 is a plan view showing the conventional representation of a talking machine record, sound box and tone armwith my present improvements applied to the same. Fig. 2, an enlarged plan view, partly in section, of my improved stop mechanism. Fig. 3, a sectional view on an enlarged scale on the line'3, 3 of Fig. 1 looking in the direction of the arrows. Fig. 4, a section on the line 4, 4 of Fig. 2 on an enlarged scale. Fig. 5 a plan view, part1 in section, of a modified arrangement in w ich a single arm is used fordeterminin the tripping point and also for tripping t e brake, the section being taken on the line 5, 5 of Fig. 6 looking in the direction of the arrows. Fig. 6, an end elevation of Fig. 5 showing in full lines the position of the tone arm and pivoted determining-tripping arm in the trip ing osition, and in dottedlines the positlon o the same parts when the tripping-determining arm has moved to cause the trigger pin to be moved to lock the brake in its withdrawn position. Fig.7, a section on the lines 7, 7 of Fig. 6 in the direction of the arrows, the brake being tripped to stop the turn table. Fig. 8, an elevation, partly in section, corresponding to the dotted line position'of Fig. 6. Fig. 9, a longitudinal sectional view corresponding to Fig. 7, the brake being in its withdrawn position, and Fig. 10 a separate detail of the annular toothed lower end of the determining-tripping arm. In all of the above views corresponding parts are represented by the same reference numerals.

Referring first to Fig. 1, the turn table 1 is provided with the usual center pin 2, on which is mounted the record 3. A tone arm 4 carries the sound box 5, having a st lus 6, cooperating with the record groove. ith

the preferred embodiment of my invention,

I use a brake lever 7 pivoted on a small circular plate 8, and having a rubber bufier or shoe 9, adapted to engage the periphery of the turn table 1 when the brake 1s re leased to stop the record. The brake lever 7 is actuated when tripped by the usual spring 10. In Fig. 1 the brake lever is shown as being tripped to arrest the rotation of the turn table, and in Fig. 2 the brake lever is illustrated in a withdrawn position.. The plate 8 is formed with an up turned arm 10, into which is mounted a small spring barrel 1.1. The trigger pin 12 extends through the barrel 11, and a coiled spring 13 normally forces the trigger pin to the position shown in Fig. 4. The trigger pin 12 is provided with a head 14 thereon having a cam-like inner face, as shown. A determining arm 15 is connected with the barrel 11, whereby the barrel acts as a pivot for said lever. spring washer 16 is interposed, and maintained under tension, be tween the face of the arm 10 and the cap 17 of the barrel. By reason of the spring washer 16, it will be seen that when the determining arm 15 is moved to any angular position it will remain in that position frictionally. A tripping lever 18 is pivoted near the lower end of the determining arm 15, and is provided with an incline cam 19 adapted to be forced into engagement with the cam surface of the head 14 to thus withdraw the trigger pin and release the brake. When the tripping lever 18 is parallel with the determining arm 15 (see dotted lines Fig. 3) the cam 19 will have withdrawn the trigger pin 12 to release the brake. This corresponds to the trippin position of the brake. In operation, if it is desired to stop the record inthe last groove, the tone arm is moved to bring the stylus 6 into the last groove, which can be readil done by simply moving the stylus over tie smooth inner portion-of the record until the stylus engages and is arrested by the last groove of the record. The determining arm 15 and tripping lever 18 are now moved simultaneously until they engage with the tone arm. When this engagement takes place the trigger pin 12 will be withdrawn. Having thus determined the point where the brake is to bereleased, the tone arm 4 is now moved toward the beginning of the record and as it moves to the position shown in the full lines in Fig. 3, the tripping lever 18 will be moved with respect to the determining arm by the tension of the s ring 13 and the engaging cam surfaces. his permits the trigger pin 12 to move to the locking posi tion shown in Fig. 4. The brake lever 7 may now be moved, causing the finger 2O thereon to engage behind the end of the trigger pin (see Fig. 2) and thus lock the brake withdrawn. The movement of the tripper lever 18 with respect to the determining arm 15 may be limited by a pin 21. The brake being thus locked in its withdrawn position, the turn table will commence to move and the record will be played in the usual way. As the tone arm 4 approaches the end of the record it comes into contact with the tripping lever 18 at the full line position, Fig. 3, and gradually moves the said lever toward the position shown in dotted lines. When the tripping lever has been moved to its original position a of adjustment, corresponding to that of the determining arm 15, the cam 19 will have withdrawn the trigger pin entirely to release the brake and permit the same to be applied to thus arrest the turn table. It Will be obvious that the extent through relationship between the determinin which the tripper arm 18 moves in thus releasing the brake is determined'automati- .cally and is always fixed and certain and also that therelease .point is always prede- .,end.of the trigger pin, I prefer to employ iterminedand exact. In case of wear on the to the record. For instance, the stylus lever .6 may, be 'engaged with the last groove and the adjusting screw 22 may be regulated to cause the brake to be tripped one or two grooves inward from the last groove. Such .an adjustment may be desirable where the inertia of the parts to be'arrested is relativelygreat with respect to the braking effeet, and where twoor three turns may be required to bring those parts to rest.

, In Figs. 5 to 10, inclusive, I illustrate a modified arrangement involving the same inventive thought, but wherein a single lever is used having the double function of tripping the trigger pin as well as determining the point where the release-of the brake is to be effected. With this modification, the brake comprises a plunger 23 carrying at itsinner end a friction pad made of cork, rubber or similar material A brake lever 25 pivoted to the plate 26 is provided with a finger 27 entering a groove 28 in the plunger 23, whereby the lever 25 may be moved tothe dotted line position shown in Fig. 5 towithdraw the brake plunger.- A spring 29 actuates the lever 25 to apply the brake when released. The plate 26 isprovided with an upturned portion 30 forming a bearing for the plunger 23 and with a similar portion'31 forming a bearing for a barrel '32. Where the plunger 23 passes through the'barrel 32 it is made blade-like in cross section, as shown at 33, so that the plunger may move longitudinally with respect to thebarrel like a keyina Yale look, but rotary movement of the barrel will also rotate the plunger. A spring washer 34 is interposed between the upturned portion 31 and a nut 35 to hold the barrel 32 in any angular )osition to which it may be adjusted. single determining armand tripping lever 36 is mounted on the barrel 32 so as to be capable of independent angular movement with respect to the barrel. This arm 36 is formed with aneye 37 encircling the barrel'and constituting the pivot of'the arm, and it is also provided with a groove 38 in which is located thefiattenedend of the plunger. The groove 38 is formed between the two teeth 39' and 4:0 in the eye 37 ,(see Fig. 10),, and the flattened end of the plunger is formed with a notch 41 on its under side, which notch, when the brake plunger is entirely withdrawn, will be brought into line with the tooth 39, as shown in Fig. 9. With this modified form of the invention, the tone arm is first moved to the position where it is to be arrested corresponding generally with the last record groove, and the arm- 36 is then moved, as shown in Fig. 6, into engagement with said tone arm. During this adjustment the brake plunger is in its released position shown in Figs. 5 and 7. Having thus made the de sired determination, the tone arm is then moved toward the beginning of the record groove and thetnrn table is started by movingthe brake lever 25 into position shown in dotted lines in Fig. 5. This frees the turn table which thereupon commences to rotate.

As long as the flattened portion oi the plunger 23 remains in the groove 38, the plunger will not be locked in its withdrawn position, but as soon as the notch 11 conies into line with the tooth 39 the lever 36 will then betree to moveby gravity to the position shown in dotted lines Fig. 6. This brings the tooth 39 withinthe notch ll and locks the brake plunger withdrawn. At the same time the tooth 40 coming in contact with the shoulder 42 of the barrel 32 (see Fig. 8 limits the independent secondary movement of the arm 36 from its position the brake will be released and will thus be impelled into contact with the turn table to arrest rotation thereof. Although it is possible, as explained, to carry out the invention by the use of a single arm performing the double function of first determining the brake releasing point and then moving independently to permit the locking of the brake, I prefer to use two separate arms as shown in Figs. 1 to 4: inclusive, because in this way a somewhat simpler arrangement can be constructed and moreover it becomes possible to readily provide for accurate adjustment to take up any wear by a simple adjusting screw such as 22.

Having now described my invention, what I claim as new therein and desire to secure by Letters Patent is as follows:

'1.In a stop mechanism for talking machines, the combination with the tone-arm, ofa spring actuated brake, a trigger for locking the brake 1n 1ts wlthdrawn position.

means whereby the trigger may be released by the tone-arm traversing the record, and

means cooperating with the tone-arm for automatically determining the releasing poinlil; of said trigger, substantially as set ort a 2. In a stop mechanism for talking machines, the combination with the tone arm and a s ring actuated brake of a trigger for normal y locking the brake in its withdrawn position, means actuated b the tone arm which traverses the record 'or withdrawing the trigger to release the brake, means cooperating with the tone arm for determining the releasing point of said trigger, and means for automaticall moving the trigger into position to hold t e brake withdrawn after its releasin point has been determined, substantial y as set forth.

3. In a stop mechanism for talking machines, the combination with the tone arm of a spring actuated brake, a trigger pin for locking the brake in a withdrawn position, a determinin arm cooperatin with the tone arm for eterminin the point at which the trigger pin releases t e brake, and a triping lever carried by the determining arm or releasing the brake when the tripping osition is reached, substantially as set orth.

4. In a stop mechanism for talking machines, the combination with the tone arm of a 5 ring actuated brake, a trigger pin for loc 'ng the brake in a withdrawn position, a determinin arm cooperating with the tone arm for etermining the point at which the trigger pin releases the brake, and a tripping lever carried by the determining arm for releasing the bra e when the tripping position is reached, said tripping arm having automatic predetermined movement with respect to the determining arm to provide for the engagement of the trigger pin with the brake, substantially as set forth.

5. In a stop mechanism for talking machines, the combination with the tone arm of a spring actuated brake, a trigger pin for locking the brake in a withdrawn position, a determining arm e06 erating with the tone arm for determining t e point at which the trigger pin releases the brake, a tripping lever carried b the determining arm for releasing the bra e when the tripping position has been reached, and an adjustable stop for regulating the movement of the tripping lever with respect to the determining arm, substantially as set forth.

6. In a stop mechanism for talking machines, the combination with the tone arm, of a spring actuated brake, a barrel with friction means to hold it in any position of rotary adjustment, a trigger pin mounted lon itudinally in said barrel for locking the bra e withdrawn, a determining arm cooperating with the tone arm, and connected to the barrel for adjusting its rotative position,

and a tripping lever pivoted on the arm for withdrawing the trigger pm to release the brake, substantially as set forth.

This specification signed and witnessed this 13th day of June, 1919.

HAROLD L. TUNISON.

Witnesses:

FRANK L. Damn, C. D. JORDAN.

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