PIVOT MECHANISM AND KEYBOARD APPARATUS INCLUDING THE SAME

• US 20190378486A1
• Filed: 08/26/2019
• Published: 12/12/2019
• Est. Priority Date: 03/24/2017
• Status: Active Grant

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: KAMIYA, Hirotsugu, ICHIKI, Shunsuke, SATO, Tsuyoshi
• Granted Patent: US 10,825,435 B2
• Time in Patent Office: Days
• CPC Class Codes: G10C 3/12 Keyboards; Keys
• CPC Class Codes: G10H 1/346 Keys with an arrangement for simulating the feeling of a piano key, e.g. using counterweights, springs, cams

Abstract

A pivot mechanism includes: a shaft portion; a bearing configured to contact the shaft portion and pivot about a pivot axis; and a reinforcement protruding from an outer circumferential surface of the shaft portion. The outer circumferential surface includes a first region contactable by the bearing in a range of its pivotal movement and a second region not including the first region in a region opposed to the first region via the pivot axis. The reinforcement extends from at least a portion of the second region to an outside of the bearing in a pivot-axis direction.

Claims

1. A pivot mechanism, comprising:

a shaft portion;

a bearing configured to contact the shaft portion and pivot about a pivot axis; and

a reinforcement protruding from an outer circumferential surface of the shaft portion, the outer circumferential surface comprising a first region contactable by the bearing in a range of pivotal movement thereof and a second region not comprising the first region in a region opposed to the first region via the pivot axis, the reinforcement extending from at least a portion of the second region to an outside of the bearing in a pivot-axis direction.

2. The pivot mechanism according to claim 1,

wherein the bearing comprises a first receiver and a second receiver that contact the shaft portion at different positions in a pivotal direction,

wherein a first end and a second end of the second receiver as opposite ends thereof in the pivot-axis direction are located between a first end and a second end of the first receiver as opposite ends thereof in the pivot-axis direction, and

wherein the outer circumferential surface of the shaft portion comprises a third region contactable by the first receiver in a range of pivotal movement thereof and a fourth region not comprising the first region in a region opposed to the third region via the pivot axis, and the reinforcement extends from at least a portion of the fourth region to the outside of the bearing in the pivot-axis direction.

3. The pivot mechanism according to claim 1,

wherein the bearing comprises a first receiver and a second receiver that contact the shaft portion at different positions in a pivotal direction, and

wherein the outer circumferential surface of the shaft portion comprises a third region contactable by the first receiver in a range of pivotal movement thereof, and the reinforcement is provided at a position intersecting an imaginary plane that is perpendicular to the pivot axis and that contains an end portion of the third region in the pivot-axis direction.

4. The pivot mechanism according to claim 1, wherein the reinforcement is a protrusion protruding to a position outside a shaft diameter of the shaft portion.

5. The pivot mechanism according to claim 1, further comprising a shaft supporter configured to support the shaft portion,

wherein the reinforcement is connected to the shaft supporter.

6. The pivot mechanism according to claim 2, wherein the bearing comprises a plurality of first receivers each as the first receiver.

7. The pivot mechanism according to claim 6, wherein the first receiver is located at opposite ends of the bearing in the pivot-axis direction.

8. The pivot mechanism according to claim 1, wherein the reinforcement comprises:

a portion protruding from the second region; and

a portion protruding from a region located outside the bearing in the pivot-axis direction when viewed from the second region.

9. The pivot mechanism according to claim 1,

wherein the bearing comprises a first end and a second end in the pivot-axis direction, and

wherein a portion of the reinforcement protrudes from an inner region interposed between the first end and the second end in the pivot-axis direction, and another portion of the reinforcement protrudes from an outer region not interposed between the first end and the second end in the pivot-axis direction.

10. The pivot mechanism according to claim 1, further comprising a shaft supporter connected to an end portion of the shaft portion in the pivot-axis direction and configured to support the shaft portion,

wherein the reinforcement is connected to the shaft supporter.

11. A pivot mechanism, comprising:

a shaft portion;

a bearing configured to contact an outer circumferential surface of the shaft portion and pivot about a pivot axis; and

a reinforcement protruding from the outer circumferential surface of the shaft portion in a direction orthogonal to a pivot-axis direction,

wherein the reinforcement is configured such that a position, in the pivot-axis direction, of a boundary of a region in which the outer circumferential surface of the shaft portion contacts the bearing is located between a first end and a second end of the reinforcement in the pivot-axis direction.

12. A keyboard apparatus, comprising:

a key;

a hammer assembly configured to, in response to pressing of the key, pivot about a pivot mechanism comprising (i) a shaft portion, (ii) a bearing configured to contact the shaft portion and pivot about a pivot axis, and (iii) a reinforcement protruding from an outer circumferential surface of the shaft portion, the outer circumferential surface comprising a first region contactable by the bearing in a range of pivotal movement thereof and a second region not comprising the first region in a region opposed to the first region via the pivot axis, the reinforcement extending from at least a portion of the second region to an outside of the bearing in a pivot-axis direction;

a sensor disposed below the key and configured to detect an operation on the key; and

a sound source section configured to produce a sound waveform signal in response to an output signal of the sensor.

13. The keyboard apparatus according to claim 12, wherein the outer circumferential surface of the shaft portion comprises a fifth region that receives load from the bearing in response to pressing of the key, and the reinforcement extends to an outside of the bearing in the pivot-axis direction from at least a portion of a region opposed to the fifth region via the pivot axis.