JPH0736395Y2 - Electronic musical instrument key switch - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sheet switch used for an electronic musical instrument, which improves the responsiveness in a switching action by allowing air to be supplied to and discharged from a sealed space provided between each contact. It was done like this.

(Prior Art) The applicant had previously devised a key switch for an electronic musical instrument as shown in FIG.

In this figure, 1 is the body of the wind instrument,
The bottom surface of the body 1 is formed by the back cover 3. A predetermined space is formed inside the body 1, and projecting portions 5 projecting from the inner wall surface of the body 1 and facing each other are formed in the space. A printed circuit board 7 is fixed to these protrusions 5.

A tact switch 9 is placed and fixed on the center of the upper surface of these printed circuit boards 7. Above the tact switch 9, a push rod (actuator) 13 supported by a top wall of the body 1 so as to be vertically movable via a guide 11 is arranged.

On the other hand, the body 1 is provided with a key shaft 15 via a key post (not shown), and a bent portion of an L-shaped key arm 17 is rotatably supported on the key shaft 15. One end of the key arm 17 is arranged above the push rod 13, and the other end thereof is biased by a spring 20 so as to abut the side wall of the body 1 via a stopper 19.

Therefore, when the key arm 17 is pressed against the spring 20, the push rod 13 is pushed down. As a result, the contacts are short-circuited via the built-in snap plate, the tact switch 9 is turned on, and a specific pitch is designated.

(Problems to be solved by the invention) However, in a key switch of an electronic musical instrument using such a tact switch, a snap action does not occur unless a certain pressing force is applied, and a touch feeling during playing is provided. The problem was that it was not good. Therefore, it is possible to adopt a flat type membrane switch. This is one in which conductive paste contacts are printed on a pattern sheet and arranged so as to face each other in an enclosed space.

However, in such a so-called sheet switch, the space in which the contacts are arranged so as to face each other is sealed by the pattern sheet as described above, so that in the return operation after the contacts are in close contact with each other, There is a problem in that the speed varies and the reliability of the switch is poor.

(Means for Solving Problems) Therefore, the present invention defines a predetermined space by interposing between a pair of layered members fixed to each other inside the musical instrument body so as to face each other. A spacer, a pair of contact members respectively supported by the pair of layered members and arranged to face each other at a predetermined distance in the space, and one of the pair of layered members is pressed to press the above. A key switch for an electronic musical instrument comprising an actuator capable of short-circuiting a pair of contact members, wherein a communication passage for communicating the space with the outside is provided and an air pocket is provided in the middle of the communication passage. It is an object of the present invention to solve the above-mentioned problems by providing.

(Operation and Effect) In the key switch of the electronic musical instrument according to the present invention, one of the layered members is pressed by the actuator to short-circuit the contact members. Here, the space defined by the spacer and these layered members communicates with the outside through a communication passage. Therefore, in the switching operation, when the contacts come into contact with or separate from each other, the air is discharged and supplied into the space through the communication passage. That is,
When the switch is turned off, the return movement of the layered member that supports the contacts becomes faster. Further, an air reservoir is provided in the middle of the communication passage to prevent dust and the like from entering the space and prevent contact failure.

(Embodiment) An embodiment of the key switch of the electronic musical instrument according to the present invention will be described below with reference to the drawings.

1 to 4 show an embodiment of a key switch of an electronic musical instrument according to the present invention.

In these figures, 22 is the body of the electronic wind instrument.
Is shown. The bottom of the tube body 22 is closed by a back lid 24,
A space having a rectangular cross section is formed inside thereof.

A so-called sheet switch (flat type membrane switch) 26 is installed in this space.

This sheet switch 26 is provided with horizontal bottom walls 28, 28 of the tubular body 22.
It is supported on a pair of plastic rails 30, 30 each having a U-shaped cross section, which are respectively erected on the rails.

That is, as shown in FIG. 2, the sheet switch 26 has a strip-shaped thin reinforcing plate (for example, a steel plate having a predetermined strength) 32 as a whole on the upper surface of the same strip-shaped upper sheet (a layered member having a predetermined thickness). 34 and a lower sheet (a layered member having a predetermined thickness) 36 are laminated with a spacer 38 interposed therebetween.

Therefore, as shown in detail in FIG. 3, a spacer 38 defines a sealed space 40 between the upper sheet 34 and the lower sheet 36, which is vertically separated by a predetermined distance (the thickness of the spacer). Then, as shown in FIG. 2, the seat switch 26
Are arranged along the extending direction of the pipe body 22, and the spaces 40 are also arranged in a plurality of rectangular shapes.

In the space 40, the lower surface of the upper sheet 34 and the upper surface of the lower sheet 36 are opposed to each other and have substantially circular contact points 4 respectively.
2 and 44 are printed. The contacts 42 and 44 are formed by printing a predetermined pattern with, for example, silver paste on the polyester film 34, and by plating the polyimide flexible double-sided sheet 36 with gold. The spacer 38 is made of a polyester film which is an insulating material and has a predetermined thickness.

Further, as shown in FIG. 1, a rubber underlay member 46 for absorbing a mounting error is disposed on the lower surface of the metal reinforcing plate 32. Then, these sheet switches 26 include the pair of rails 30 and 30 and the tubular body 22 in the internal space of the tubular body 22.
Both ends in the width direction of these strip-shaped members are fixed by being sandwiched between a pair of protrusions 48, 48 protruding inward by a predetermined amount at a predetermined height position from the inner surface of the side wall.

Here, as shown in FIG. 2, the respective sealed spaces 40 of the respective switches 26 are communicated with each other by a predetermined passage 50. In addition, a space located at one end of the strip-shaped member in the longitudinal direction.
40 communicates with an air reservoir 52 of a predetermined volume via a communication passage 50A, and the space that is the air reservoir 52 communicates with the outside through an air vent passage (communication passage) 50B.

Further, in FIG. 2, reference numeral 54 is a chip diode for displaying ON / OFF of the switch, and a plurality of chip diodes are arranged in a rectangular hole 56 formed in the upper sheet 34 and the spacer 38. In addition, reference numerals 58 and 60 in the figure denote connector portions of the contacts 42 and 44 of the upper sheet 34 and the lower sheet 36, respectively.

As shown in FIG. 1 again, above the upper seat 34, a push rod 64 supported by a guide 62 slidably in a vertical (up and down) direction is arranged. The push rod 64 is provided immediately above each contact 42, 44 of the switch 26 and functions as an actuator that short-circuits these contacts 42, 44. Further, as shown in FIG. 4, the push rod 64 has a rubber cap 66 attached to the lower end thereof so that its curved surface abuts (point-contacts) the upper surface of the upper sheet 34.
68 is a cavity of the cap 66. The above guide
62 is fixed to the upper wall of the pipe body 22.

Further, a key arm 70 similar to that shown in FIG. 5 is swingably supported by a key shaft 72 outside the tube body 22. When one end of the key arm 70 is pressed down, the push rod 64 is pressed down to close the switch 26. The push rod 64 is pulled by the tension of the upper seat 34.
Returns to the initial position, and the key arm 70 returns to the initial state by the spring 74 (FIG. 1 shows these initial states). Reference numeral 76 is a stopper such as felt fixed to the other end of the key arm 70.

In the key switch 26 of the electronic wind instrument having the above configuration, the push rod is pushed by pressing the key arm 70.
By depressing 64, the contacts 42 and 44 are brought into contact with each other and short-circuited to specify a predetermined pitch.

In this case, since the seat switch 26 is used, the switching action is performed with a low pressing force.

Then, in this switching operation, each switch 26
Since the sealed space 40 is always in communication with the outside through the communication passages 50A and 50B, it is easy to discharge and supply air into the space. As a result, the responsiveness of the switch 26 as a whole could be improved. That is, the return operation speed of the contact 42 is higher than that in the conventional case. Contacts 42, 44
They will not stick to each other.

Also, in this switching operation, each key switch 26
Will be pressed during the performance. As a result, the air in any of the spaces 40 is discharged, and the speed of the switching operation is maintained by the air supply / discharge action. At this time, dust is trying to invade the space 40 from the outside when air is supplied or discharged, but since the air pool 52 is disposed in the middle of the communication paths 50A and 50B with the outside, this air pool 52 The dust and the like will be stored inside, and will not enter the space 40 and adhere to the surfaces of the contacts 42 and 44.

That is, in the key switch 26 according to the present embodiment as a whole, by appropriately setting the spring constants of the key arm 70 and the return spring 74 thereof, an appropriate feeling can be generated for the pressing force of the player. ,
The contact 42 is pushed down through the seat 34, and the air vent communication path
Since the contacts 50A and 50B are arranged in the space 40 of the contact 42, the switching action can be rapidly performed by a constant small pressing force.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a key switch of an electronic musical instrument according to the present invention, FIG. 2 is a schematic plan view of the same embodiment, and FIG. 3 is an enlarged sectional view of a main part of the embodiment. 4 and 5 are longitudinal sectional views of an actuator of one embodiment, and FIG. 5 is a longitudinal sectional view showing a key switch of an electronic musical instrument. 22 …… Tube (musical instrument body), 26 …… Sheet switch, 34…
… Upper sheet (layered member), 36 …… Lower sheet (layered member), 38 …… Spacer, 40 …… Space, 42,44 …… Contact,
50A, 50B ... Communication passage, 52 ... Air reservoir, 64 ... Push rod (actuator).

Claims (1)

[Scope of utility model registration request] 1. A pair of layered members fixed to face each other inside a musical instrument body, spacers interposed between these layered members to define a predetermined space, and the pair of layered members respectively. A pair of contact members supported and arranged to face each other in the space at a predetermined distance, and an actuator capable of short-circuiting the pair of contact members by pressing one of the pair of layered members. A key switch for an electronic musical instrument, comprising a communication passage for communicating the space with the outside and an air reservoir provided in the middle of the communication passage.