# US 10,311,847 B2 · Keyboard apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,311,847 B2 - Document ID: US10311847B2 - Status: Granted - Kind: B2 - Application number: 15/924,838 - Filed: 2018-03-19 - Published: 2018-10-04 - Granted: 2019-06-04 - Earliest claimed: 2017-04-04 - Assignees: Yamaha Corporation - Applicants: Yamaha Corporation - Inventors: Shunsuke Ichiki; Hirotsugu Suzuki; Ichiro Osuga - Web page: https://patentgrep.com/patent/US10311847B2 ## CPC - G10H 1/346: {Keys with an arrangement for simulating the feeling of a piano key, e.g. using counterweights, springs, cams} - G10H: ELECTROPHONIC MUSICAL INSTRUMENTS; INSTRUMENTS IN WHICH THE TONES ARE GENERATED BY ELECTROMECHANICAL MEANS OR ELECTRONIC GENERATORS, OR IN WHICH THE TONES ARE SYNTHESISED FROM A DATA STORE ## Abstract A keyboard apparatus includes: a key; a frame; and a connecting portion configured to connect the key and the frame to each other. The connecting portion includes a flexible member having a rod shape and having flexibility that enables the key to pivot with respect to the frame. The flexible member includes a portion that, in entirety of a range of pivotal movement of the key, maintains a state in which a length of a line extending along a neutral axis of the flexible member between two points located on the neutral axis is greater than a length of a straight line connecting the two points to each other. ## Claims ### Claim 1 A keyboard apparatus, comprising: a key; a frame; and a connecting portion configured to connect the key and the frame to each other, the connecting portion comprising a flexible member having a rod shape and having flexibility that enables the key to pivot with respect to the frame, wherein the flexible member comprises a portion that, in entirety of a range of pivotal movement of the key, maintains a state in which a length of a line extending along a neutral axis of the flexible member between two points located on the neutral axis is greater than a length of a straight line connecting the two points to each other. ### Claim 2 (depends on 1) The keyboard apparatus according to claim 1, wherein the neutral axis is an axis extending along a direction in which the flexible member extends. ### Claim 3 (depends on 1) The keyboard apparatus according to claim 1, wherein the straight line connecting the two points located on the neutral axis comprises a component in a direction along a plane on which the key pivots. ### Claim 4 (depends on 1) The keyboard apparatus according to claim 1, further comprising a plurality of keys each as the key, wherein the straight line connecting the two points located on the neutral axis comprises a component in a direction in which the plurality of keys are arranged. ### Claim 5 (depends on 1) The keyboard apparatus according to claim 1, wherein at least a portion of the flexible member comprises: a first straight rod portion extending in a longitudinal direction of the key; a second straight rod portion extending in an up and down direction; and an intermediate rod portion having a rod shape, connecting the first straight rod portion and the second straight rod portion to each other, and extending in a direction different from each of the longitudinal direction and the up and down direction. ### Claim 6 (depends on 5) The keyboard apparatus according to claim 5, wherein one of the first straight rod portion and the second straight rod portion is disposed nearer to the key than another of the first straight rod portion and the second straight rod portion, and wherein said another of the first straight rod portion and the second straight rod portion is disposed nearer to the frame than the one of the first straight rod portion and the second straight rod portion. ### Claim 7 (depends on 1) The keyboard apparatus according to claim 1, wherein, in at least a portion of the range of the pivotal movement of the key, an angle between a longitudinal direction of the key and a direction in which the flexible member extends at a first position is less than 45 degrees, and an angle between the longitudinal direction of the key and a direction in which the flexible member extends at a second position is greater than 45 degrees. ### Claim 8 (depends on 1) The keyboard apparatus according to claim 1, wherein, in at least a portion of the range of the pivotal movement of the key, an extending direction in which the flexible member extends changes by greater than or equal to 90 degrees in a change in the extending direction from a third position to a fourth position on the flexible member. ### Claim 9 (depends on 1) The keyboard apparatus according to claim 1, wherein the neutral axis comprises a corner portion. ### Claim 10 (depends on 1) The keyboard apparatus according to claim 1, wherein the neutral axis comprises a curve. ### Claim 11 (depends on 1) The keyboard apparatus according to claim 1, wherein an area of the flexible member in cross section perpendicular to the neutral axis is deferent between the two points. ### Claim 12 (depends on 1) The keyboard apparatus according to claim 1, further comprising a guide configured to restrict movement of the key with respect to the frame in a longitudinal direction of the key. ### Claim 13 A keyboard apparatus, comprising: a key; a frame; and a connecting portion configured to connect the key and the frame to each other, the connecting portion comprising a flexible member having a rod shape and having flexibility that enables the key to pivot with respect to the frame, wherein the flexible member comprises a portion that, in entirety of a range of pivotal movement of the key, maintains a state in which a neutral axis of the flexible member is bent. ### Claim 14 A keyboard apparatus, comprising: a key; a frame; and a connecting portion configured to connect the key and the frame to each other, the connecting portion comprising a flexible member having a rod shape and having flexibility that enables the key to pivot with respect to the frame, wherein at least a portion of the flexible member comprises: a first straight rod portion extending in a longitudinal direction of the key; a second straight rod portion extending in an up and down direction; and an intermediate rod portion having a rod shape, connecting the first straight rod portion and the second straight rod portion to each other, and extending in a direction different from each of the longitudinal direction and the up and down direction.