Pivot mechanism and keyboard apparatus

• US 10,665,217 B2
• Filed: 09/17/2018
• Issued: 05/26/2020
• Est. Priority Date: 03/25/2016
• Status: Active Grant

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Ichiki, Shunsuke
• Primary Examiner(s): Horn, Robert W
• Application Number:
  US16/132,970
• Publication Number:
  US 20190043463A1
• Time in Patent Office: 617 Days
• CPC Class Codes: G10B 3/12 Keys or keyboards; Manuals
• CPC Class Codes: G10C 3/12 Keyboards; Keys
• CPC Class Codes: G10H 1/34 Switch arrangements, e.g. keyboards or mechanical switches specially adapted for electrophonic musical instruments
• CPC Class Codes: G10H 1/346 Keys with an arrangement for simulating the feeling of a piano key, e.g. using counterweights, springs, cams
• CPC Class Codes: G10H 2220/285 with three contacts, switches or sensor triggering levels along the key kinematic path

Abstract

A pivot mechanism includes: a shaft portion; a bearing configured to contact the shaft portion at a first contact and a second contact and configured to pivot about a pivot axis relative to the shaft portion; and a supporter secured to the bearing, configured to contact the shaft portion at a third contact, and bendable in a direction different from a direction from the pivot axis toward the third contact.

Claims

1. A pivot mechanism providing for an attachment between a stationary part and a pivotable part, the pivot mechanism comprising:

a shaft with a shaft length portion and ends, at least one of the ends being secured to one of the stationary part and the pivotable part;

a shaft length portion receiver secured to the other of the stationary part and the pivotable part and comprising a c-shaped member, made of a flexing material, defining an opening in which the shaft is to be inserted, the shaft length portion receiver being configured to contact the shaft at a first contact and a second contact and configured to pivot about a pivot axis relative to the shaft;

an arm secured to either an end or an intermediate part of the c-shaped member and extending away from the opening, the arm comprising an elbow at one end of the arm; and

a blocker arm, made of a flexing material, extending from the elbow to face the opening of the shaft length portion receiver and having a blocking position when the blocker arm is not flexed and a non-blocking position when flexed, the blocker arm being configured to contact the shaft at a third contact, and bendable in a direction different from a direction from the pivot axis toward the third contact,

wherein a distance between the pivot axis and the third contact is less than each of a distance between the pivot axis and the first contact and a distance between the pivot axis and the second contact.

2. The pivot mechanism according to claim 1, wherein each of an angle, centered about the pivot axis, between the first contact and the second contact, an angle, centered about the pivot axis, between the second contact and the third contact, and an angle, centered about the pivot axis, between the third contact and the first contact is less than 180 degrees.

3. The pivot mechanism according to claim 1,

wherein each of the first contact and the second contact is located on an inner surface of the shaft length portion receiver in the opening, and

wherein a size of the opening at an open end of the shaft length portion receiver is greater than or equal to a largest diameter of the shaft.

4. The pivot mechanism according to claim 1,

wherein a movable range of the shaft length portion receiver with respect to the shaft comprises a first region and a second region comprising an end portion of the first region,

wherein the blocker arm is engaged with a portion of the shaft when the shaft length portion receiver is located in the first region, and

wherein, when the shaft length portion receiver is located in the second region, the blocker arm is not engaged with the shaft and is bendable until the shaft length portion receiver becomes separable from the shaft.

5. The pivot mechanism according to claim 1, wherein the blocker arm is bendable in a direction tangent to a cross section of a contact surface of the shaft at the third contact that is a position at which the blocker arm and the contact surface of the shaft contact each other.

6. The pivot mechanism according to claim 1, wherein each of a cross-sectional shape of the shaft or the shaft length portion receiver at the first contact and a cross-sectional shape of the shaft or the shaft length portion receiver at the second contact is an arc shape centered about a point on the pivot axis.

7. The pivot mechanism according to claim 1, wherein each of a cross-sectional shape of the shaft or the shaft length portion receiver at the first contact and a cross-sectional shape of the shaft or the shaft length portion receiver at the second contact is an arc shape centered about a point on the pivot axis.

8. A pivot mechanism providing for an attachment between a stationary part and a pivotable part, the pivot mechanism comprising:

a shaft with a shaft length portion and ends, at least one of the ends being secured to one of the stationary part and the pivotable part;

a shaft length portion receiver secured to the other of the stationary part and the pivotable part and comprising a c-shaped member, made of a flexing material, defining an opening in which the shaft is to be inserted, the shaft length portion receiver being configured to contact the shaft at a first contact and a second contact and configured to pivot about a pivot axis relative to the shaft;

an arm secured to either an end or an intermediate part of the c-shaped member and extending away from the opening, the arm comprising an elbow at one end of the arm; and

a blocker arm, made of a flexing material, extending from the elbow to face the opening of the shaft length portion receiver and having a blocking position when the blocker arm is not flexed and a non-blocking position when flexed, the blocker arm being configured to contact the shaft at a position on the pivot axis, and bendable in a direction away from at least one of the first contact and the second contact.

9. The pivot mechanism according to claim 8,

wherein each of the first contact and the second contact is located on an inner surface of the shaft length portion receiver in the opening, and

wherein a size of the opening at an open end of the shaft length portion receiver is greater than or equal to a largest diameter of the shaft.

10. The pivot mechanism according to claim 8, wherein the blocker arm is bendable in a direction different from a direction normal to an outer circumferential surface of the shaft at a contact that is a position at which the outer circumferential surface of the shaft and the blocker arm contact each other.

11. The pivot mechanism according to claim 8,

wherein a movable range of the shaft length portion receiver with respect to the shaft comprises a first region and a second region comprising an end portion of the first region,

wherein the blocker arm is engaged with a portion of the shaft when the shaft length portion receiver is located in the first region, and

wherein, when the shaft length portion receiver is located in the second region, the blocker arm is not engaged with the shaft and is bendable until the shaft length portion receiver becomes separable from the shaft.

12. The pivot mechanism according to claim 8, wherein the blocker arm is configured to be bent in a direction tangent to a contact surface of the shaft at a contact between the contact surface of the shaft and the blocker arm.

13. A keyboard apparatus, comprising:

a key;

a hammer assembly configured to pivot, in response to pressing of the key, about a pivot mechanism providing for an attachment between a stationary part and a pivotable part, the pivot mechanism comprising (i) a shaft with a shaft length portion and ends, at least one of the ends being secured to one of the stationary part and the pivotable part, (ii) a shaft length portion receiver secured to the other of the stationary part and the pivotable part and comprising a c-shaped member, made of a flexing material, defining an opening in which the shaft is to be inserted, the shaft length portion receiver being configured to contact the shaft at a first contact and a second contact and configured to pivot about a pivot axis relative to the shaft, (iii) an arm secured to either an end or an intermediate part of the c-shaped member and extending away from the opening, the arm comprising an elbow at one end of the arm, and (iv) a blocker arm, made of a flexing material, extending from the elbow to face the opening of the shaft length portion receiver and having a blocking position when the blocker arm is not flexed and a non-blocking position when flexed, the blocker arm being configured to contact the shaft at a third contact, and bendable in a direction different from a direction from the pivot axis toward the third contact;

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

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

wherein a distance between the pivot axis and the third contact is less than each of a distance between the pivot axis and the first contact and a distance between the pivot axis and the second contact.

14. A pivot mechanism providing for an attachment between a stationary part and a pivotable part, the pivot mechanism comprising:

a shaft with a shaft length portion and ends, at least one of the ends being secured to one of the stationary part and the pivotable part;

a shaft length portion receiver secured to the other of the stationary part and the pivotable part and comprising a c-shaped member, made of a flexing material, defining an opening in which the shaft is to be inserted, the shaft length portion receiver being configured to contact the shaft at a first contact and a second contact and configured to pivot about a pivot axis relative to the shaft;

an arm secured to either an end or an intermediate part of the c-shaped member and extending away from the opening, the arm comprising an elbow at one end of the arm; and

a blocker arm, made of a flexing material, extending from the elbow to face the opening of the shaft length portion receiver and having a blocking position when the blocker arm is not flexed and a non-blocking position when flexed, the blocker arm being configured to contact the shaft at a third contact, and bendable in a direction different from a direction from the pivot axis toward the third contact,

wherein the supporter is engaged with the shaft portion at the third contact and is bent with pivotal movement of the shaft portion.