US3776557A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dynamically-balanced phonograph arm
Assignee: Individual
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Filing: 1971-05-13
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Granted: 1973-12-04
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Expires: 1991-05-13
Abstract
Abstract A conventional phonograph arm consists essentially of a balanced rod on one end of which is mounted a phono pick-up device (cartridge) and at the other end a counterweight. A pivot system located near the counterweight is so arranged that the cartridge can move vertically and laterally. Such arms suffer from the fact that when the turntable is suddenly tilted or vibrated the cartridge frequently leaves the surface of the record. The present disclosure describes the use of a two-element arm where the two elements are interconnected so as to rotate in opposite directions so that rotational motions of the machine do not cause the cartridge to leave the record.
Inventors
- 👤 J Rabinow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:13
CPC Classifications
G; G11; G11B; G11B3/00; G11B3/02; G11B3/10; G11B3/12; G11B3/14
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
213 words
A. Pivot bearing for a cartridge supporting arm for a phonograph record player, comprising b. a single point pivot bearing between the frame of the record player and the arm, c. said bearing comprising a pointed element fitting into a conical dimple element, one of said elements being fixed to said frame and the other of said elements being on a surface of said arm, d. and a supplementary single point pivot bearing located at the opposite surface of the arm from its bearing element, such that the line connecting the two pivot bearings is substantially at right angles to the longitudinal axis of the arm, e. said supplementary bearing being mounted on a flexible spring supported member which has a limited spring compliance in the direction of said longitudinal axis but is rigid in the direction perpendicular to the arm and parallel to the plane of a record being played, so that it can move in a direction parallel to the axis of the arm, but not in a direction which is at right angles to the arm and parallel to tHe plane of the record, so as to restrain the arm from rocking on the first single point pivot bearing, about an axis parallel to the longitudinal axis of the arm.
Claim 2
Dependent Claim
213 words
A. Pivot bearing for a cartridge supporting arm for a phonograph record player, comprising b. a single point pivot bearing between the frame of the record player and the arm, c. said bearing comprising a pointed element fitting into a conical dimple element, one of said elements being fixed to said frame and the other of said elements being on a surface of said arm, d. and a supplementary single point pivot bearing located at the opposite surface of the arm from its bearing element, such that the line connecting the two pivot bearings is substantially at right angles to the longitudinal axis of the arm, e. said supplementary bearing being mounted on a flexible spring supported member which has a limited spring compliance in the direction of said longitudinal axis but is rigid in the direction perpendicular to the arm and parallel to the plane of a record being played, so that it can move in a direction parallel to the axis of the arm, but not in a direction which is at right angles to the arm and parallel to tHe plane of the record, so as to restrain the arm from rocking on the first single point pivot bearing, about an axis parallel to the longitudinal axis of the arm.
Claim 3
Dependent Claim
103 words
a. A phonograph record player comprising a frame supporting a disc record for rotation in the horizontal plane, b. a pick-up cartridge for playing such a disc record, c. supporting means mounted on said frame for supporting said cartridge, d. said cartridge-supporting means comprising two rotatably supported members, one of said members being arranged to hold said cartridge, e. the second of said members arranged to support a supplementary cartridge-balancing mass, f. and means to couple the said two members for counter-rotation so that when one of said members rotates in one direction, the other of said members rotates in the opposite direction.
Claim 4
Dependent Claim
103 words
a. A phonograph record player comprising a frame supporting a disc record for rotation in the horizontal plane, b. a pick-up cartridge for playing such a disc record, c. supporting means mounted on said frame for supporting said cartridge, d. said cartridge-supporting means comprising two rotatably supported members, one of said members being arranged to hold said cartridge, e. the second of said members arranged to support a supplementary cartridge-balancing mass, f. and means to couple the said two members for counter-rotation so that when one of said members rotates in one direction, the other of said members rotates in the opposite direction.
Claim 5
Dependent Claim
39 words
The invention according to claim 2, g. said members being so balanced that a horizontal or vertical rotary or displacement force applied to the members through the frame produces no net rotation of the members relative to the frame.
Claim 6
Dependent Claim
48 words
The invention according to claim 2, g. one of said members being an arm carrying the cartridge at one end and being pivoted near its opposite end, h. the second member being an arm with one end carrying a balancing mass and being pivoted near the other end.
Claim 7
Dependent Claim
30 words
The invention according to claim 4, g. wherein the coupling means comprises two meshing gears, one being mounted on one member and the other being mounted on the other member.
Claim 8
Dependent Claim
31 words
The invention according to claim 4, g. said coupling means being a mechanical link arranged to transmit pivotal motion from one of said members to the other in the opposite sense.
Claim 9
Dependent Claim
13 words
The invention according to claim 6, h. said link comprising a flexible wire.
Claim 10
Dependent Claim
32 words
The invention according to claim 2, g. wherein the coupling means is so arranged that when the cartridge tends to move up, the supplementary mass tends to move down and vice versa.
Claim 11
Dependent Claim
49 words
The invention according to claim 2, g. wherein the coupling means is so arranged that when the first member rotates clockwise relative to the frame, the second member rotates counterclockwise relative to the frame, this relative action occuring in both the vertical and horizontal planes relative to the frame.
Claim 12
Dependent Claim
156 words
a. A phonograph disc record player comprising a frame, b. a first arm element having a phonograph cartridge at one end, said arm being pivotally mounted on a bearing on the said frame at the other end for limited pivotal motion of the arm in the direction perpendicular to the plane of a record being played, c. a counter-mass element on a second arm displaced from the first arm in a direction perpendicular to the plane of the record, said second arm being similarly pivoted on a bearing on the frame at a point displaced from the first arm in a direction perpendicular to the plane of the record and intermediate its ends, d. coupling means connecting said two arms adjacent to the said two bearings and arranged so that when the first arm tends to pivot on its bearing in one direction the counterweight arm tends to pivot about its bearing in the opposite direction.
Claim 13
Dependent Claim
156 words
a. A phonograph disc record player comprising a frame, b. a first arm element having a phonograph cartridge at one end, said arm being pivotally mounted on a bearing on the said frame at the other end for limited pivotal motion of the arm in the direction perpendicular to the plane of a record being played, c. a counter-mass element on a second arm displaced from the first arm in a direction perpendicular to the plane of the record, said second arm being similarly pivoted on a bearing on the frame at a point displaced from the first arm in a direction perpendicular to the plane of the record and intermediate its ends, d. coupling means connecting said two arms adjacent to the said two bearings and arranged so that when the first arm tends to pivot on its bearing in one direction the counterweight arm tends to pivot about its bearing in the opposite direction.
Claim 14
Dependent Claim
44 words
The invention according to claim 10, e. said two bearings each having freedom of rotation in directions both perpendicular and parallel to the record being played, whereby the tone arm is counter-balanced against rotational acceleration forces transmitted through the frame in both said directions.
Claim 15
Dependent Claim
24 words
The invention according to claim 11, f. at least one of said bearing comprising a pointed male element fitting loosely into a conical depression.
Claim 16
Dependent Claim
167 words
a. A phonograph record player comprising a frame supporting a disc record for rotation in the horizontal plane: b. a first arm element having a phonograph cartridge near one end and a first pivotal bearing near the other end, said pivotal bearing having two relatively movable elements, supporting the arm for piVota movement, c. one of said elements being mounted on said frame and the other on said arm, d. a counter-mass arm element having a second pivotal bearing near one end thereof, the other end being free, with the center of gravity of said mass lying over said first arm and the bearing of the counter-mass arm being displaced from said first pivotal bearing along a line parallel the line of said first arm; e. coupling means connecting said two arms intermediate of said two bearings, and arranged so that when said first arm tends to pivot on its bearing in one direction, the counter-weight arm tends to pivot about its bearing in the opposite direction.
Claim 17
Dependent Claim
167 words
a. A phonograph record player comprising a frame supporting a disc record for rotation in the horizontal plane: b. a first arm element having a phonograph cartridge near one end and a first pivotal bearing near the other end, said pivotal bearing having two relatively movable elements, supporting the arm for piVota movement, c. one of said elements being mounted on said frame and the other on said arm, d. a counter-mass arm element having a second pivotal bearing near one end thereof, the other end being free, with the center of gravity of said mass lying over said first arm and the bearing of the counter-mass arm being displaced from said first pivotal bearing along a line parallel the line of said first arm; e. coupling means connecting said two arms intermediate of said two bearings, and arranged so that when said first arm tends to pivot on its bearing in one direction, the counter-weight arm tends to pivot about its bearing in the opposite direction.
Claim 18
Dependent Claim
18 words
The invention according to claim 13, f. at least one of said pivotal bearings being a knife-edge bearing.
Claim 19
Dependent Claim
41 words
The invention according to claim 13, f. said pivotal bearings being knife-edge bearings, g. a sub-frame supporting said bearings, h. and a gimbal supporting said sub-frame, i. said gimbal being mounted on the phonograph player for rotation about a vertical axis.
Claim 20
Dependent Claim
72 words
a. A cartridge support structure for a phonograph record player which includes b. a first means to support a cartridge for pivotal movement about an axis and c. a second means to pivotally support a counterweight for said cartridge, d. and means to couple said first and second supporting means so that when the cartridge moves pivotally about said axis in one direction, the counterweight counter rotates pivotally in the opposite direction.
Claim 21
Dependent Claim
72 words
a. A cartridge support structure for a phonograph record player which includes b. a first means to support a cartridge for pivotal movement about an axis and c. a second means to pivotally support a counterweight for said cartridge, d. and means to couple said first and second supporting means so that when the cartridge moves pivotally about said axis in one direction, the counterweight counter rotates pivotally in the opposite direction.
References Cited (Backward Citations)
FR501608A
Cited
US3378267A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |