JPH03659Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a keyboard switch used in an electronic keyboard instrument.

Conventionally, in an electronic keyboard instrument, as shown in the first diagram, when a key is pressed, a leaf spring contact piece A that is interlocked with the key is opened from a contact point b of a leaf spring contact piece B and comes into contact with a contact point c of a leaf spring contact piece c. Using a keyboard switch configured to allow a key to be touched, a musical tone corresponding to the touch of a key is obtained by detecting the difference in opening time between contact piece A and contact pieces B and C. There is.

In the keyboard switch, leaf spring contact pieces B and C
is held in a bent state by stoppers D and E, and the contact piece B is separated from the stopper D by the spring force of the contact piece A when the key is released.

Thus, when the key is pressed and the contact piece A is moved upward from the state shown in the first diagram when the key is released, the contact piece B is temporarily moved upwardly.
When it comes into contact with the stopper D, the contact piece A is opened, but just before this opening, between the contact piece A and the contact point b, the contact piece B held by the stopper D is opened. Since the contact is loaded with a spring force due to the deflection of the contact piece B, the contact piece B does not undergo natural vibration after opening, and no spark is generated at the time of opening.

Further, when the key is pressed further after the contact piece A is opened from the contact piece B, the contact piece A comes into contact with the contact point c of the contact piece C, but in this case as well, immediately after the contact, the contact piece A causes the contact piece C to separate from the stopper E. The spring force due to the deflection of contact piece C is applied to contact piece A.
join. In this way, even when the key is hit hard, the contact piece C separates from the contact piece A and does not undergo natural vibration, and no chattering occurs.

As described above, this type of conventional keyboard switch has high electrical reliability, but in order to operate as described above, contact pieces A, B, and C must be bent at a predetermined angle. However, if the accuracy of the bending process is low, due to the variation in the angle, a predetermined contact load cannot be obtained when the contact piece A and the contact point b and the contact piece A and the contact point c come into contact, causing sparks and pushing. There is a problem in that it is not possible to accurately detect the difference in opening time between the contact piece A and the contact pieces B and C, which correspond to the length of the key, and it is difficult to manufacture, and the bending angle may be incorrect during manufacture or maintenance inspection. There were some inconveniences, such as the possibility that this may occur.

The purpose of the present invention is to eliminate such inconveniences of the conventional technology, and the first leaf spring contact piece 2 that interlocks with the key 1 when the key is pressed is replaced by the second and third leaf spring contact pieces when the key is released. 3 and 4, and the first leaf spring contact piece 2 and the second and third leaf spring contact pieces 3 and 4 open with a time difference when the key is pressed, The leaf spring contact pieces 2, 3, 4 are provided with mounting pieces 5, 6, 7 formed by bending on both sides of the base end, and at least one tip edge of the mounting pieces 5, 6, 7 8
The first, second and third leaf spring contact pieces 2, 3, 4
The first, second, and third leaf spring contact pieces 2 are formed so as to be inclined with respect to the surface of the base plate 10, and the claw pieces 9 provided on the tip edge 8 are inserted into the holes 11 of the base plate 10 and bent.
3 and 4 are attached along the substrate 10.

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 2 and 3, the first plate spring contact piece 2
(hereinafter referred to as the first contact piece 2) includes a protrusion 12 formed by bending into a U-shape at the distal end, mounting pieces 5, 5 formed by bending on both sides of the base end, Contact points 13A fixed to the front and rear of the protrusion 12, respectively;
13B, and the tip edge 8 of the mounting pieces 5, 5
is a claw piece 9 formed to be inclined at a predetermined angle with respect to the surface of the first contact piece 2, and for attachment to the substrate 10.
has. This first contact piece 2 is the claw piece 9 of the mounting piece 5.
was fitted into the hole 11 of the substrate 10, bent, and attached to the substrate 10 at a constant distance by soldering as necessary. A protrusion 12 at the tip of the first contact piece 2 that is not bent at a predetermined angle with respect to the substrate 10 presses against the lower surface of the key 1 in the released state, and when the key 1 is strongly hit, the first contact piece 2 This is to prevent chattering caused by the natural vibration of the first contact piece 2 due to separation between the key 1 and the key 1. The second leaf spring contact piece 3 and the third leaf spring contact piece 4 (hereinafter referred to as the second contact piece 3 and the third contact piece 4) have contacts 14 and 15 fixed to their tips, respectively, and contacts 14 and 15 on both sides of the tips. Stopper pieces 16, 16, 1 formed by bending
7, 17, and mounting pieces 6, 6, 7, 7 formed by bending on both sides of the base end, the second contact piece 3
The leading edge 8 of the mounting piece 6 is formed parallel to the surface of the second contact piece 3, and the leading edge 8 of the mounting piece 7 of the third contact piece 4 is formed parallel to the surface of that contact piece. They are formed to be inclined at a predetermined angle, and both have claw pieces 9 for attachment to the substrate 10. These second and third contact pieces 3,
4 are arranged in a straight line in the length direction of the first contact piece 2,
The claw pieces 9, 9 of the mounting pieces 6, 7 are inserted into the holes 11 of the board 10.
It was fitted onto the substrate 10, bent, and soldered as necessary to be mounted on the substrate 10 at a constant distance. mounting pieces 6 for the second and third contact pieces 3, 4;
7, the angle of inclination of its tip edge 8 with respect to the surface of the contact piece, and the length of the stopper pieces 16, 17, so that when the key is released, the contacts 14, 15 of the second and third contact pieces 3, 4 are
A second contact piece 3 contacts the contacts 13A and 13B of the contact piece 2 with a pressure greater than a predetermined contact load, and moves downward together with the first contact piece 2 when the key is pressed to move the first contact piece 2 downward.
The difference in opening time between the first contact piece 2, the second contact piece 3, and the third contact piece 4 due to the stopper pieces 16 and 17 of the third contact piece 4 contacting the base plate 10 back and forth causes the movement of the key. Furthermore, the contact loads of the second contact piece 3 and the third contact piece 4 with respect to the first contact piece 2 immediately before they are separated from the first contact piece 2 are set to a necessary minimum so as to have a constant relationship with the length. Set to be greater than or equal to the value.

In FIG. 2, 18 is a keyboard chassis, and the board 10 is attached to the keyboard chassis 18 using a spacer 19.
It was fixed through.

The substrate 10 had a wiring pattern on its lower surface, and the first, second, and third contact pieces 2, 3, and 4 were connected to the wiring pattern.

The attachment piece 5 at the base end of the first contact piece 2 is made to protrude obliquely to the length direction of the first contact piece 2 and bent parallel to the length direction, as shown in the fourth diagram. It may also be formed by

Further, in the embodiment, the first and third contact pieces 2, 4
Although the distal edges 8 of the mounting pieces 5 and 7 are inclined with respect to the surfaces of the contact pieces, only the first contact piece 2 may be used, and the distal edge 8 of the second contact piece 3 may also be inclined. .

Next, its operation will be explained.

When key 1 is pressed in the released state shown in the second diagram,
The first contact piece 2 moves downward in conjunction with the key 1, and the second and third contact pieces 3 and 4 follow this movement. When the stopper piece 16 of the second contact piece 3 comes into contact with the board 10, the contact 13A of the first contact piece 2 and the second contact piece 3
The contact 14 is opened. Furthermore, in conjunction with key 1,
When the contact piece 2 moves downward, the stopper piece 17 of the third contact piece 4
contacts the substrate 10, and the contact 13B of the first contact piece 2 and the contact 15 of the third contact piece 4 are opened. Stopper piece 1
6 and 17 contact the board 10, the second contact piece 3 and the third contact piece 4 are in a slightly bent state, so that the predetermined contact load is applied to the contacts 13A and 14 and the contacts 13B and 15. It is created from the added contact state,
Therefore, the second contact piece 3 and the third contact piece 4 do not chatter due to free vibration after opening, and no sparks are generated. Even when transitioning from the key-pressed state to the key-released state, the contacts 13A and 14
Since a predetermined contact load is applied between the contacts when the contacts 13B and 15 come into contact, no chattering due to free vibration occurs and no sparks are generated.

In this way, according to the present invention, the first, second and third leaf spring contact pieces 2, 3, 4 are provided with mounting pieces 5, 6, 7 formed by bending on both sides of the base end. death,
The tip edge 8 of at least one of the mounting pieces 5, 6, and 7 is formed to be inclined with respect to the surface of the contact piece, and the claw piece 9 provided on the tip edge 8 is fitted into the hole 11 of the substrate 10. Since the first, second and third leaf spring contact pieces 2, 3 and 4 were attached along the board 10 by bending, the first, second and third leaf spring contact pieces 2, 3 and 4 were attached. There is no need to perform any bending work, there is no risk of generating sparks due to variations in bending angle, and the first contact piece 2, second contact piece 3, and third contact piece 4 are
It has the advantage that it can always be opened with a constant time difference with respect to the moving length of , and it is also easy to manufacture.

[Brief explanation of the drawing]

FIG. 1 is a side view of a conventional keyboard switch, and FIG. 2 is a side view of an embodiment of the present invention in a key-released state.
Figure 3 is an exploded perspective view of the main parts, Figure 4A is the first
FIG. 4B is a perspective view of a modification of the leaf spring contact piece 2, and FIG. 4B shows a partially developed view thereof. 1...Key, 2...First plate spring contact piece, 3...Second
Leaf spring contact piece, 4...Third leaf spring contact piece, 5, 6, 7
...Mounting piece, 8...Tip edge, 9...Claw piece, 10
...Substrate, 11...hole.

Claims (1)

[Scope of utility model registration request] A first plate spring contact piece 2 that interlocks with the key 1 as the key is pressed.
contacts the second and third leaf spring contact pieces 3 and 4 when the key is released, and the first leaf spring contact piece 2 and the second and third leaf spring contact pieces 3 and 4 contact each other with a time difference when the key is pressed. In the one that opens, the first, second and third leaf spring contact pieces 2,
3 and 4 are provided with mounting pieces 5, 6, and 7 formed by bending on both sides of the base end, and the mounting pieces 5, 6, and 7 are
is formed such that at least one tip edge 8 thereof is inclined with respect to the surfaces of the first, second, and third leaf spring contact pieces 2, 3, and 4, and a claw piece 9 provided on the tip edge 8 is attached to the substrate 1.
1. A keyboard switch characterized in that first, second and third leaf spring contact pieces 2, 3 and 4 are attached along a base plate 10 by fitting into holes 11 of 0 and bending them.