US1453613A - Tone-arm support - Google Patents

Description

' May 1, 192.3. 1,453,613 1.. R. WOLFF TONE ARM SUPPORT Filed Sent. 29 1921 Patented May 1, 1923. v

UNITED STATES LORENZ nfwoLrr, or Los ANGELES, CALIFORNIA.

TONE-ABM surroa'r.

Application filed September 29, 1921. Serial No. 504,076.

To all whom it may concern Be it known that I, LORENZ R. l/VoLFF, a citizen of the United States, residing at Los Angeles, county ofLos Angeles, and State of California, have invented a new and useful Tone-Arm Support, of which the following is a specificatio'n.

My invention relates to phonographs and more particularly to a tone arm support for the same.

Phonographs as at present manufactured are provided with a reproducer carried at 'the forward end of a hollow arm which is universally pivoted to a tone arm bracket mounted in the tone chamber of a phonograph.

In some instruments it is the practice to support the entire'weight of the tone arm and reproducerfon the playing point of the needlethat rests on the record during the playing of the record. This is injurious to the record, the needle, and quality of tone produced.

Some manufacturers of phonographs recognized this injurious effect and have tried to overcome its effect by shortening the pivoted length of the tone arm. This construc tion was also faulty inasmuch as the combined weight of the reproducer and that 39 part of the tone arm in front ofthe pivot point carrying the reproducer is too heavy.

In a tone arm support produced according to my invention, as much weight as desired can be brought to bear upon the record at the point of reproduction, which is, where the needle is in contact with the record groove. I A 1 In records ofthe type inwhich the sound impressions are recorded in the side of thegroove, it is only necessary to apply enough weight at the point of reproduction to make the needle follow the groove. I have found that by the use of my tone arm support I can adjust the weight at the point of production to such a degree that all scratchy noises heretofore produced, especially by records containing grit, are greatly eliminated.

In the reproduction of records that have become warpedyby the action of heat and time, the rise and fall of the undulations are followed perfectly by. a tone arm provided.

with my support and no apparent difference in reproduction from that produced by, a

5 flat record is noticed.

One of'the principal objects of my invenlow the undulating or uneven surfaces of a' phonograph record.

Other objects and advantages w ll be made evldent hereinafter.

Referring to the drawing which is for il-- lustrative purposes only,

Fig. 1 -is a side elevation of a phonograpl tone arm provided with my support.

Fig. 2 is a top plan view of my tone arm support shown-attached to the tone arm mounting. Fig. 3 is a sectlon on line 33 of Fig. 2.

Fig. 4 is a section on line 1-1 of Fig 2.

Fig. 5 isa section of the adjusting nut on line 55 of Fig. 2.

Fig. 6 is a face view of the tone arm supporting yoke.

Fig. 7 is avertical sectional view of the supporting post for the tone arm and rela ted parts.

The tone arm 5 consists of a horizontally disposed cylindrical member having mounted thereon at the outer end a reproducer 6 which carriesthe needle 7, such needle belng shown 1n engagement with a record 8. The inner end of the tone arm terminates 1n a vertically disposed portion having a rounded end which is pivotally mounted on a pin 9 supported in a collar 13 which is revolvably mounted in the tone arm post 10. A stationary bracket'11 is securedsby screws 12 to the revolvable collar 13 of the arm post 10, which post 10 is secured to the top board 15 of the phonograph. 'Pivotally mounted on trunnion screws 16, in ears 17,1 on the bracket 11 is a carrying arm 18. Thecarrying arm 18 is provided with resilient supporting means for the tone-arm which consist of a yoke 20 mounted on the outer ends of wire springs 21. The springs slidably extend through holes 23 in a downwardly depending flange 24 formed on the carrying arm 18 and have their inner ends fixed in the clamping nut 29 drawing'the block 25 tightly against the under side of the arm 18 when the nut is screwed down on the stud 26.

c Interposed between the bracket 11 and i the arm 18 isan adjustable spring 30. The

' lower end of the spring 30 is provided with a plug 32 in which is revolvably secured the reduced end of a threaded stud 33 provided with a lock nut 34 and a knurled head35. The stud 33 may be screwed up or down in the threaded outer end 36 of the bracket '11 and locked in any desired position by the lock nut 34.

The yoke 20 consists of a block 40 into which the outer ends of the springs 21.are secured and a U shapedthroat or supporting member 41 for the .outer end 0 the tone arm.; v

The inner face of the throat 41 is preferably made half round so as to ofier the least frictional resistance to that part of the tone arm resting upon the same,

The operation of my tone arm support is as follows: 1

' en a phonograph tone arm and its component parts are assembled, it has been found in practice, that. the 'variation of weight in'these parts produce a variation of tone q uality.

By ad usting the distance between. the arm 18 and the outer end of the bracketll, so that-the spring 30 will almost counterbalance the weight of the tone arm and then volvable collar on said adjusting the length of the springs-21 so that the required resiliency is given the tone arm an ideal -condition is acquired.

I have found in practice that records used on a phonograph provided with my tone -arm support, .show no perceptible wear after such use and that the steel needle which ordi narily can only be used with success ,for one or two reproductions may beused in connection with my device many times.

e llhave shown and described my invention as applied to a single piece tone arm it is to be understood that my tone arm support may be used on various types of tone arms whether made in one piece or of jointed types without departing'from the Spirit of my invention.

' ll claim as my invention:

1. in combination, a tone arm post, a rest, a tone arm pivotally mounted in said collar, a .bracket fixed to said collar, an arm pivotally mounted on said bracket, apair of wire springs slidably extendin through a portion of said arm, means or fixingsaid springs to said arm, a yoke fixed to the outer end of said springs arranged to receive and support the outer end of said tone arm, a coiled spring interposed between said arm and said bracket and means forvarying the tension on said coiled spring.

2. In combination, a tone arm'post, a revolvable collar on said post, a tone arm pivotally mounted in said collar, a bracket fixed to said collar, an arm pivotally mounted on said bracket; a yielding member slidably mounted on said arm, meanson said member for supporting said tone arm, a coiled spring interposed between said arm and said bracket and meansv for varying the tension of said coiled spring;

3. In combination, atone arm post, a revolvable collar on said post, a tone arm pivotally mounted in said collar, a bracket fixed to said collar. an arm pivotally mounted on said bracket, a pair of wire springs slidably extending t rough a portion of said arm, means for xing said springs to said arm, a yoke fixed to the outer end of said springs arranged to receive and supportthe outer end of said tone arm, and a yielding member interposed between said arm and said bracket.

4. In combination, a tone arm post, a revolvable collar on said post, a tone arm pivotally mounted in said collar, a bracket fixed to said collar, an arm pivotally mount-' ed on said bracket, a yielding member mounted on saidarm, means on said member for supporting said tone arm, and a yielding member interposed between said arm and said bracket.

5. In combination, a tone arm post, a revolvable collar on sald post, a tonearm pivotally mounted in said collar, a bracket mounted on said collar, ayielding member pivotally mounted on said bracket-to swing vertically thereon, means on said yielding member arranged to engage and support the outer end of said (tone arm, and means for garying the tension'on said yielding memv 6. In combinationja tone arm support, a tone arm pivotally and revolvably mounted in said support, a bracket movable with said tone arm, an arm pivotally mounted on said bracket toswing vertically thereon, and a yielding member mounted on said arm arranged to yieldingly support the outer and of said tone arm. In testimony whereof. I have hereunto se my hand atLos' Angeles, California, this 21st day of September 1921.

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