US2489941A - Record changer - Google Patents

Description

1 Shets-Sheet 1 b&

M- A. WALKER RECORD CHANGER Nbv. 29, 1949 Filed May a, 1944 M- A WALKER ATTORNEY Nov. 29, 1949 M. A. WALKER 2,489,941

RECORD CHANGER Filed May s,--1944 4 Shee ts-Sheet 2 m ENVENTOR.

M- A- WALKER I BY MW ATTORNEY Filed ma 3, 1944 4 Sheets-Sheet; s

I N VEN TOR.

BY WALKER V MQ ATTORNEY Nov. 29, 1949 A. WALKER RECORD CHANGER Filed May '6, 1944 4 Sheets-Sheet 4 3 4 i m 1 M m M 5 L H a m s- 5 a R U) 4 0 +1 i I f l "a m INVENTOR. H M-A-WALKER ATTORNEY Patented Nov. 29 1949 UNITED STATES PATENT OFFICE RECORD CHANGER Milton A. Walker, San Jose, Calif.

Application May 3, 1944, Serial No. 533,819

7 Claims.

The present invention relates to improvements in record changers, and has particular reference to phonographs designed to allow a plurality of records to be played in automatic succession and without the intervention of any human agency.

While phonographs of this type are well known and in common use at the present time, it is proposed to introduce a new method of operation which has not been contemplated heretofore as far as I am aware.

More particularly, it is proposed to use a process in which air under pressure is introduced between a record and its support, such as a turntable or another record lying underneath, to facilitate sliding movement of the record on its support.

It is further proposed to use the force of gravity for moving the record, this force being created through a slight inclining of the record supporting table or tables.

It should be particularly understood that the interposing of the air film makes it practical to use the force of gravity for sliding the record from one table to another, the air film serving the purpose, not only of breaking contact between two adjacent records so as to prevent injury to the grooves of the records, but also that of furnishing an anti-friction bearing for the record to be moved, whereby the latter will respond to a very slight inclination.

And finally, it is proposed to provide certain other improvements in details of construction, as well as in the general plan to render my basic idea available for practical purposes.

Further objects and advantages of my invention will appear as the specification proceeds, and the novel features of my record changer will be fully defined in the claims hereto attached.

The preferred form of my invention is illustrated in the accompanying drawings forming part of this application, in which:

Figure 1 shows a vertical longitudinal section through the main operating mechanism of my record changer;

Figure 2, a top plan view of the record changer;

Figure 3, a horizontal section taken along line 33 of Figure 1;

Figure 4, a detail view of a microphone pick-up arm and its operating mechanism;

Figure 5, a vertical section through the armoperating mechanism;

Figure 6, a horizontal section taken along line 6-6 of Figure 1; and.

Figure '7, a wiring diagram explaining the sequence of operations,

While I have shown only the preferred form of my invention, I wish to have it understood that various changes or modifications may be made within the scope of the claims hereto attached, without departing from the spirit of the invention.

Referring to the drawing in detail, my apparatus may be accommodated in any suitable cabinet I, which may be rectangular in form and may comprise a bottom 2, end walls 3 and side walls 4. A top 5 for the cabinet is formed with a large opening 6 adapted to accommodate and give access to the records and the main working mechanism.

A base board 1 of any suitable width is hinged to one of the end walls, as at 8 and extends substantially through the length of the cabinet in spaced relation to the bottom of the same, and its free end is supported on a cam 9 secured upon a large wheel I0 adapted to be driven by the motor ll. 1

Rotation of the cam through one-half of a revolution causes the base board to dip or tilt, while a further rotation through one-half a revolution causes the base board to return to horizontal position.

The base board carries a U-shaped wall l2 which serves as a guide for guiding the records from one table to another, as will be more fully described hereinafter. The upper portion of the guide may be provided with a suitable felt lining as indicated at I3.

The base board further carries, intermediate its length, a post 14, which pivotally supports a beam l5 having two forked ends l6 and l! on which the table assemblies rest.

My apparatus comprises two table assemblies, one for the rotary table 29 adapted to carry a stack of records 2| to be played, and one for the non-rotating table 22 adapted to receive the records which have been played.

The two table assemblies are supported on the ends of the beam l5 by means of cupped discs 23-24, and the non-rotating table assembly is weighted, as at 25, to be always heavier than the rotating table assembly, even if all the records are stacked on the latter.

The supporting means for the non-rotating table assembly comprises a tube 26 rising from the base board and secured thereto by means of a holding plate 21 fixed to the underside of the base board by means of rivets 28, and a tube 29 de-' pending from the table and telescoped on the tube 28.

An air tube 30 extends centrally through thetubes 26 and 29, and connects, below the base board, with a main air tube 3 l. The upper end of the air tube 39, which is fixed in its position, is on a level with the top of the table when the latter is in its uppermost position, or on a level with the topmost record placed on the table, so as to serve as a centering pin for the records. The tube terminates in a small orifice or let, as at 32, for allowing air to escape therethrough.

The table 22 is lowered stepwise, by the thickness of one record, Whenever record is received on the table. The apparatus brin ing about this effect comprises a stepped block 33 having steps 34 corresponding in depth to the thickness of a record, a foot 35 depending from the tube 29 and adapted to rest on one of the steps, and op rating means for the block, whereby the latter is pulled to the left by the width of one step each time a record is received on the table.

The operating means for the block comprise an electromagnet 36 pulling against spring 31.

The core 3? ofthe electro-ma'gnet. which has a bend to limit its inward motion, terminates in an arm 38 running alongside of the block, and the arm and the block are provided with suitable pawl and ratchet arrangement til-Ail, whereby the block is pulled to the left by the width of one step each time the electro-magnet is energized. A spring 4!! tends to push the core outward for a new bite.

The foot 35 bearing against the vertical wall of each step serves as a stop for holding the block in position after each move. The block is formed with a lengthwise slot 49 by means of which it is made to straddlethe tube 26, and movement toward the right beyond the extreme position shown in Figure 1 is prevented by the end wall of the slot. 7

, The rotary or turntable assembly includes a tube rising from the base board 1, a motor assembly 46 mounted underneath the turntable and comprising a non-rotary part 4? and a rotary part 48, a tube 49 projecting downwardly from the non-rotary part of the motor and telescoped over the tube 45, a third tube 5!! rising from the concave disc 24 and telescoped over tube 49, ,5

spring means 5| for urging the concave disc and non-rotary part of the motor apart, and releasable means 52 for locking tube 58 to tube 49 and for holding the disc 24 and the non-rotary part of the motor in fixed relation.

The contacting faces of the tubes 4.5, 49 and 50 are made non-circular or polygonal, so as to prevent relative rotation and to hold the part 4! of the motor against rotation.

The motor 46 may be made of any suitable type, and is here shown as comprising, in its nonrotating part, a laminated core disc 52 and a series of coils 53 supported on arms 54 projecting from the upper end of the tube 49; and, in its rotary part 48, a laminated ring rotor, secured upon the lower face of the turntable 2E). The latter has a depending annular flange 55 resting on the upper end of the tube 49, which is suitably widened to furnish a bearing surface.

The means 52' for releasably IOOkihg the tube 50 to tube 49 comprise a rack 56 on tube 49, a pinion 51 mounted on tube 5i; to mesh with the rack, and a solenoid 58 having a plunger 59 normally locking the pinion against rotation. When the solenoid is energized, the plunger is withdrawn and relative adjustment may be made between the two tubes. The switch 95 for the solenoid is arranged for convenient manual opera mu.

Thus, normally, the concave disc 24, the tubes 49 and 50, and the non-rotating part of the motor form a rigid assembly, movable as a unit, but the length of this unit may be adjusted, depending upon the number of records used, to bring the top record into the proper position with. re spect to the remainder of the apparatus when the beam i5 is in the starting position, shown in Figure 1.

When in playing position, the top record should be located immediately above the top plane of the table 22, or if the latter carries records, above the top plane of the uppermost record carried thereby.

An air tube (it extends centrally through the tube 35, the table and the record assembly thereon, and is connected, through a flexible hose 8!, with the main air tube 3i It is normally urged upward to come flush with the top face of the uppermost record, by means of a spring 62 bearing at one end upon a cage 53 secured to the bottom face of the base board 7?, and at its upper end upon a disc 64' secured upon the air tube.

When the topmost record is to be removed, by the sliding motion developed in the invention,

the air tube has to be retracted by the thickness of the record, and this is accomplished by means of a solenoid B5 acting on a coupling 66 of magnetizable material, this coupling being connected to the hose 6| by means of a nipple 6i of nonmagnetizable material.

The air tube Gil is formed with a reduced orifice or nozzle 68 at its upper end.

A third air tube H3 rises from the main tube 3i along the edge of the table 252 nearest the cabinet wall to which the base board 7 is pivoted.

This tube is provided with a lateral nozzle ii directed at the plane between the two uppermost records and is intended to biow a film of air underneath the topmost record.

The film of air will relieve binding contact between the uppermost record and the next one and will start sliding movement of the record toward the second table as soon as the baseboard is tilted. The record thus practically floats on air, all friction is eliminated and the record will start moving in response to a very slight gravitational force.

The space between the two tables is occupied by a cover plate 12, the top of which is on a level with the top or table 22 (when empty) and the top of the second record on table 20, so that the top faces of the table 22, the cover plate i2 and the second record form a common plane which the top record may slide, supported by the air cushion, from one table to the other, when the common plane is tilted.

The cover plate 12 has two air tubes projecting therethrough on opposite sides of the centerline of the two tables. The latter tubes connect with the main tube 3| and extend to the top of the cover plate, where they discharge through nozzle M.

The main air tube is controlled by an electri-- cally operated valve 15. This valve is operated in timed relation to the tilting of the base board,

so that when the board is tilted, the air blows between the two uppermost records from tube iii to create an air film or an air float allows the record to start moving, the tube Gil having been withdrawn sufficiently to clear the record.

As the record slides down the inclined plane formed by the second record, the cover plate 72 and the second table, the air tubes S8, 13 and 38 75 successively supply the necessary air to maintain the air film, and the record thus easily gravitates upon the table 22, being guided by the U-shaped guide I2 and its lining which stop the record when it becomes centered over the table 22.

The microphone pickup arm 80' may be mounted in a post I rising from a bracket 82, which latter may be secured upon the U-shaped guide I2, at one side of the turn table. The post is revolvable about a pin 83 (Figure 4) l and the arm is pivoted in the post with freedom of swinging movement in a vertical plane.

The post M has a brace 84 projecting over the arm 80, and the brace carries an electro-magnet 85 disposed above an intermediate section of the arm 80. The electro-magnet carries a core 86 of magnetizable material and the arm 80 has an insert 81 of the same material right underneath the core. The latter also carries a pin 88 projecting through the insert and formed with a head underneath the same.

The core 86 has a disc 81 secured thereto, and a bellows 88' connects the disc 81 and the lower end of the electro-magnet so as to form a contractible chamber about the core 86, this chamber connecting into the chamber 89 above the core, which latter is closed at the upper end by the top plate of the electro-magnet. The latter plate has a large opening 90 with a ball valve 9|, and a restricted orifice 92.

Due to this construction, when the magnet is u chamber freely escaping through the check valve As the magnet is de-energized, the insert of arm 80 naturally drops away from the core, but the amount of this drop is limited by the head of the pin 88. The core also tends to drop immediately, but its downward progress is retarded by suction, since the valve 9| automatically closes and a certain amount of time is consumed in supplying the air needed for the expansion of the bellows through the limited aperture 92. Thus the arm 89 is lifted quickly, but is let down slowly.

Horizontally, the arm 80 travels from left to right (Figure 2) while the record is being played, is then lifted by the electro-magnet, swings back to an initial position (from right to left) by gravity when the entire apparatus is tilted for transferring a record, and is let down to the new record after the top record has been transferred.

The post M has an arm 93 projecting rearwardly therefrom to close a switch 94 for energizing the electro-magnet when the arm 80 has reached the end of its inward movement.

To prepare for use, the operator first presses down on the turn table 20 to bring the concave disc 24 to its lowermost position, as indicated in Figure 1. This will bring the table 22 to its uppermost position, on a level with the top plate 12, and will cause the spring 31 to pull the stepped block 33 to the right so that foot 35 comesto rest on the highest step, suitable means being provided for disengaging pawl 39 during this operation.

The operator then places the desired number of records on the turn table 20, pushes the switch 95' (see Wiring diagram) energizing magnet 58, which unlocks the tube 49 from the tube- 50, and then allows the spring I to raise the turn table until the uppermost record is in the correct position, that is, immediately above the plane of the top plate I2 and the table 22. The switch is then released.

The sequence of operations may be best explained by means of the wiring diagram of Figure '7, in which a main line switch is shown at 95, differential relay switches 96, 91, 98 and 99, and special switch members I00, MI, and I02, and in which the wires have been lettered as shown.

Assuming that the phonograph is playing, with both switches 95 and 96 closed, and the needle reaches the end of the record so as to close switch 94, the following operations take place:

1. Current flows through wire a, 93, 94, h, wire p, opening relay of switch 96 and back to wire I); switch 96 opens; motor 46 stops.

2. Current flows through wire a, arm 93, 94, closing relay of 91, and wire I); switch 91 closes, and current flows from wire a, through relay 91, magnet and back to wire I). Magnet 85 lifts tone arm.

3. Current flows through wire a, arm 93, 94, wire (1, magnet 65, and wire e to b; magnet 65 pulls down air tube 60.

4. Current flows through wire (1, arm 93, 94, wire (1, wire closing relay of 99; wire 9, and back through c to b; closes switch 99; current flows from a through 99, magnet I5, and wires 9, e, back to b; magnet I5 opens air valve.

5. Current flows from wire a, through 93, 94, wire h, closing relay of 98, and to negative lead B; closes switch 98; current flows from positive lead A through switch 98, motor II, to negative lead B. Motor I I turns cam 9.

The record slides over, becomes centered and the tone arm swings from right to left, opening switch 94, which deengergizes solenoid magnet 65 allowing air tube 69 to rise, to act as centering pin for a new top record.

6. As the cam reaches lowermost position, contacts close at H, current flows from a through 2, I0 I, is, opening relay of 99, through g, e to I), opening 99 and stopping flow of air.

'7. Cam lifts platform I on completing one rotation and member I00 closes switch I02; temporarily current flows from wire I through I02, m, magnet 36 and back to B; magnet 36 pulls back the stepped block 34.

8. At the same time current flows from I through I02, n, and opening relay of 98, opening the latter and stopping motor II.

9. At the same time current flows from I through I02, wire 0, and closing relay of 96 to b, closing switch 96. and starting motor 46.

10. At the same time current flows from 1 through I02, wire q, opening relay for switch 91, and back to b; switch 91 opens; tone arm drops.

I claim:

1. In a record changer of the character described, two tables adapted to have records stacked thereon, a tiltable base board having a post thereon, a beam pivoted in the post and having the tables supported on the ends thereof, means operable for positioning the tables in fixed relation to the baseboard and at related elevations to allow one record to slide from one table to the other and means for tilting the base board to effect such sliding motion.

2. In a record changer of the character described, two tables adapted to have records stacked thereon, a tiltable base having a post thereon, a beam pivoted in the post and having the tables supported on the ends thereof, means operable for positioning the tables in fixed relation to the baseboard and. at related elevatitans-rte alldw-:onerreeordltoeslide :from: 55 91 .5- to the other, means for tilting the base to;-ef-.

feet; suchi slidin motionnand; means operable-for vertically-shifting the tables fafter; -arecord has beenttitansferredito again, establish related .ele

vationss 3.tIn:-a record changer -oi; the-character de-- scribed; two tables; adapted to: have. records} stacked thereon, a tiltable base board having,

acpostwthereon a beam pivoted in the post'and having theitables ,supported'onzthe ends thereof, means operable for. positioning the tables in fixed relation to the-jbaseboardgand; at related elevations to allow one record to slide-from one table 0othe other; and means for blowing ai-r;-und erneath the recordto-be moved to relieve friction for; facilitating: the..,sliding movement when the basedc'oard is tiltede.

4. 1115a record)2 changer -of the character. de-

scribed; two; tables adapted to have records stacked thereon, a platform between the tables,-

means for "positioning -thetables with respect to the platform to provide acommon plane =f0r a record to slide from one stack-to .the'other, and means forblowinggiair:underneaththe record at saidcommon plane to relievev friction .for facilitating the sliding movement of the record .whenthe plane'i -tiltedr 5. In a record changerlof the character de scribed, two, tables. adapted to. have records stacked. thereon, aplatform between, the tables, meansfor, positioning the tables with respect to the-platform to (provideacommon plane for a record to slide frombnestack to the other,-

means for tiltin the common plane. to set, up

a gravitationalforce. for, urging. the record to, move,,,and meansfor blowing. air underneathv the record to eliminate. frictional..resistance to.

the transfer.

6.. In.a..record. changer of the character described.,,two tables adapted. to 1 have records stacked thereon a platformbetween the. t l s, means for positioning the tables with respect to theplatform toprovide a common plane for a record to slide from onestack to the other, means.

fortiltingthe common planeto set upa gravitationalfforcefor. urging the recordto move, and.

meansfior. lcw sg irru dern a e o d o.

iminate fr onalsresistance o transfer, the :said means:comprising means for injecting air underneath; the-recordprogressively at the 53 upperpend oftherecordand at spaced points during its travel 7.;Ina: recordchanger of -the character described, two tables--. adaptedrto have records stacked thereon, a platform between the tables,

:meansior positioning the-tables with respect to the platform to proviole acommon plane for a record: to slidefrom-onestack to the other, means for -tilting the ;commonplane-;to.- set up a gravitational forcefqr;urg-ingthe-record to move, and means; for -blowingair underneath the record to eliminate -fr ictionalgresistanceto the transfer; the saidg means comprising means -for injectting air underneath itherrecord progressively at the upper end of therecord and at spaced points during its travel, and-:lateralsupporting means beingprovided for guiding; the record from one table to,the-othe1.--

MILTON A.- WALKER.

REFERENCES, CITED The-fo1lowing;ref.erences-are of record in the file. of patent:-

UNITED STATES PATENTS

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