JP2737135B2 - Keyboard frame mounting structure - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a keyboard frame of an electronic musical instrument or the like to a case, and when fixing the keyboard frame to the case with screws, at least two screwing surfaces of a boss into which the screws are screwed. By forming the threaded surface of the boss so that the head of the screw abuts vertically from an angle, stable screw connection is enabled.

[Prior Art] As a conventional mounting structure for a keyboard frame of this type, for example, a structure shown in FIG. 3 is known.

In FIG. 3, reference numeral 11 denotes an upper case constituting a part of the main body of the electronic musical instrument, and 13 denotes a keyboard frame fixed to the upper case 11. On the lower surface of the upper case 11, which is provided at a predetermined angle with respect to a horizontal plane (for example, the lower surface of the main body), a boss 15 is provided to project downward (α in the figure) perpendicular to the lower surface. I have. This is because switches and the like are arranged on the surface of the upper case 11 together with the display, and are normally slightly inclined forward so that the player can easily recognize the switches.

The boss 15 is formed integrally with the upper case 11, and the bolt 17 is screwed therein.

On the other hand, the keyboard frame 13 on which a plurality of keys are arranged is arranged horizontally for the sake of performance.
Is fixed below the upper case 11 by being screwed into the upper case 11. That is, the rear end of the keyboard frame 13 is
And between the bolt 17 and the head of the bolt 17 to be clamped and fixed by them.

[Problems to be Solved by the Invention] However, in such a conventional keyboard frame mounting structure, the bottom surface of the screw head is flat, and the bottom surface of the frame with which the bottom surface abuts and engages. The mounting and contact surfaces were also flat. The screw may be screwed into the boss at an angle instead of perpendicular to the frame. Therefore,
In this case, the bottom surface of the screw head is in contact with one side, and the screwing is loose when assembling the keyboard frame. As a result, there has been a problem that the keyboard frame is displaced or rattled with respect to the case after assembly.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent a screw from coming into contact with a bottom surface of a screw head, to assemble a keyboard frame reliably, and to prevent rattling and displacement of a frame after assembly.

[Means for Solving the Problems] The present invention relates to a case, a keyboard frame fixed to the case, a boss formed integrally with the keyboard frame, and a screw screwed into a threaded surface of the boss. In the keyboard frame mounting structure in which the keyboard frame is fixed to the case by screwing the screw into the boss until the screw head comes into contact with the screwed surface, the screw is screwed at at least two angles. An object of the present invention is to provide a keyboard frame mounting structure in which a screwed surface of a boss portion is formed such that a screw shaft portion is perpendicular to the screwed surface when screwed.

[Function] In the keyboard frame mounting structure according to the present invention,
The keyboard frame is fixed to the case by screwing screws into the boss.

In this case, on the contact surface where the head of the screw contacts,
The screw can abut against the abutment surface perpendicularly from at least two angles.

As a result, even when the keyboard frame is arranged at a predetermined angle with respect to the case and these must be fixed with screws, it is easy to secure the fixing with the screws, The keyboard frame can be fixed stably.

Further, since the boss and the keyboard frame are integrally formed, the boss does not move at the time of screwing, and the workability is high.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First Embodiment FIG. 1 shows a first embodiment of a keyboard frame mounting structure according to the present invention.

As shown in the figure, an upper case 21 and a lower case 23 constituting the main body of the electronic keyboard instrument are assembled and formed in a box shape. The lower case 23 has a flat lower surface, while the upper case 21 is formed to be inclined by a predetermined angle with respect to the lower surface of the lower horizontally mounted lower case 23 so that its front is lower. I have. This is because a display indicator, a switch, and the like are provided on the upper surface of the upper case 21.

The keyboard frame 25 is fixed to the upper and lower cases 21 and 23 almost horizontally.
A keyboard consisting of 27 and 29 is attached.

The front end of the keyboard frame 25 is fixed to a boss 31 projecting upward from the lower case 23 by screws 33. Further, the rear end of the keyboard frame 25 is fixed to a boss 35 provided vertically projecting downward from the lower surface on the front end side of the upper case 21 by a screw 37. This screw 37
Is for fastening the rear ends of the keys 27 and 29 overlapped with the boss 35 together.

Here, the boss 35 is disposed at a predetermined angle with respect to the keyboard frame 25 and the key rear end.

On the other hand, on the rear end side of the keyboard frame 25, a frame boss portion 41 for fixing the key rear end portion is formed so as to face the boss 35. This frame boss portion 41 integrally formed with the keyboard frame 25 projects downward and has a vertical cross section formed in a semicircular shape, and the boss portion 41 has a diameter larger than the diameter of the screw 37 in the vertical direction. Also, a large diameter hole 43 is formed. That is, the rear end portion of the keyboard frame 25 is integrally formed with a hemispherical frame boss portion 41 projecting downward.

Therefore, in the keyboard frame mounting structure according to the above configuration, the screws 37 are screwed into the bosses 35 and the keyboard frame 25 is fixed to the upper case 21.

In this case, the shaft of the screw 37 is
43 is loosely fitted and screwed into the boss 35. At this time, as described above, since the lower surface of the frame boss portion 41 with which the head (dish portion) bottom surface of the screw 37 contacts is formed in an arc shape with a predetermined curvature, the bottom surface of the screw 37 has a lower head surface. It is in contact with this arc-shaped lower surface vertically without any contact.

As a result, even if the boss 35 is inclined at any angle, the screw 37 can be screwed vertically without hitting one side,
The rear ends of the keyboard frame 25 and the keys 27 and 29 can be firmly fixed.

Also, of course, if the boss 35 of the upper case 21 is formed perpendicular to the keyboard frame 25, the screw 37 is similarly firmly fixed by the arc-shaped lower surface of the frame boss portion 41. .

Second Embodiment FIG. 2 is a sectional view showing a keyboard frame mounting structure according to a second embodiment of the present invention.

In this embodiment, the boss 63 of the upper case 61 is formed perpendicular to the keyboard frame 65. At the rear end of the keyboard frame 65, a hemispherical frame boss portion 67 integrally formed is provided.

Therefore, the screw 69 is vertically screwed into the boss 63 through the frame boss 67.

Other configurations and operations are the same as those of the above-described embodiment, and a description thereof will be omitted.

When the boss member is formed integrally with the keyboard frame, the lower surface thereof may be formed in an arcuate surface, and a tapered hole having a gradually increasing cross-sectional area may be formed in the center thereof. A bolt is loosely inserted into this tapered hole.
The upper end opening of the tapered hole has a diameter substantially equal to the diameter of the shaft of the bolt.

In this case, the bolt is screwed in according to the inclination angle of the boss (fixed portion), but the bottom surface of the bolt head is always in vertical contact with the arc-shaped lower surface by the arc-shaped lower surface.

[Effects] As described above, according to the present invention, it is possible to reliably assemble the keyboard frame by preventing the screw from coming into contact with the bottom surface of the head, and to prevent rattling and displacement of the assembled frame. it can.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a keyboard frame mounting structure according to the present invention.
FIG. 2 is a longitudinal sectional view showing a keyboard frame according to a second embodiment of the present invention. FIG. 3 is a longitudinal section showing a mounting portion of a conventional keyboard frame mounting structure. FIG. 21 Upper case, 25 Keyboard frame, 37 Screws, 41 Frame boss.

Claims (1)

(57) [Claims] 1. A case, a keyboard frame fixed to the case, a boss formed integrally with the keyboard frame, and a screw screwed into a threaded surface of the boss. By screwing the screw into the boss until the head of the key abuts, the key frame is attached to the case in a keyboard frame mounting structure. When the screw is screwed in at least two angles, the screw shaft A mounting structure for a keyboard frame, wherein a screwing surface of a boss portion is formed so as to be perpendicular to the screwing surface.