JPH0660031U - Preload structure of pressure sensitive element built into key switch - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] The key switch has a built-in key switch that improves the operability and controllability of the pointing device by applying a predetermined pressing force to the pressure sensor. The present invention relates to a preload structure of a pressure sensitive element. [Composition] When the key top 2 is attached to the specific frame 6, a preload spring 12 formed by a leaf spring is installed on the upper surface of the specific frame 6, and the upper surface of the preload spring is erected from the center of both inner ends of the metal case. A preload structure for a pressure-sensitive element incorporated in a key switch, characterized in that it is incorporated so as to be pressed by an installed spring pressing piece 3a.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a preload structure of a pressure sensitive element built in a key switch for moving and controlling a cursor position on a display of a personal computer or the like.

[0002]

[Prior art]

 Generally, in order to improve the operability of this type of electronic device, a specific key switch is equipped with a pointing function among the commonly used key switches installed on the keyboard instead of a mouse or a light pen. It is known that a normal switch function and a pointing function for controlling the moving direction of the cursor position displayed on the display can be selectively operated by operating the.

As shown in FIG. 5, a specific key switch having the above pointing function is assembled by setting a key such as an alphabetic J key which is the most convenient to operate among ordinary key switches, as shown in FIG. ing. That is, the specific key switch 1 includes a pressure sensor 4 having detection portions for pressure-sensitive elements such as pressure-resistance conversion elements at four corners on the top surface of a substantially square metal case 3, and a top surface of the pressure sensor 4. By assembling the actuator rubber 5 that pressurizes the four corners appropriately, and the click rubber 7 that attaches the boss 2a protruding from the center of the back surface of the key top 2 to the boss receiving portion 6a of the specific frame 6 so as to be vertically movable It is configured.

As described above, the specific key switch 1 is integrally assembled on the metal case 3 and attached to the J-key mounting window 8a opened in the frame 8 on the keyboard. is there. When performing the pointing operation with the specific key switch 1, first, the key top 2 is pressed directly below so that the boss 2a of the key top 2 is installed on the reinforcing plate 9 in the keyboard via the sound deadening sheet 10. The corresponding switch on the selected membrane 11 is turned on. Next, while the key top 2 is being pressed, the direction of the pressing force at the four corners of the upper surface of the key top 2 is changed, and the resistance value at the pressing position of the pressure sensor 4 equipped with the pressure sensitive element changes. The pointing function operates according to the difference in resistance change, and controls the moving direction of the cursor position displayed on the display.

[0005]

[Problems to be solved by the device]

However, as shown in FIG. 6, the characteristics of the pressure sensor 4 incorporated in the specific key switch 1 having the above-described conventional structure are as follows: the horizontal axis is the pressing force F applied to the pressure sensitive element, and the vertical axis is the resistance to the pressing force. If the value R is set, the amount of change in the resistance value R is large between F ₀ and F ₁ where the pressing force is small, and the amount of change in the output with respect to the change in the applied pressing force is not appropriate. It is a dead zone until, and even if a pressing force is applied to the pressure sensor 4 via the key switch, the moving direction of the cursor position is not accurately controlled and the pointing operation cannot be performed well. There was a problem.

The object of the present invention is to solve the above-mentioned problems of the conventional structure. By applying a predetermined pressing force to the pressure sensor in advance, the dead zone of the pressure-sensitive element can be eliminated. The present invention relates to a preload structure for a pressure-sensitive element incorporated in a key switch, which improves the operability and controllability of a pointing device by the key switch.

[0007]

[Means for Solving the Problems]

 In order to achieve such an object, according to the present invention, a resin-molded key top, a substantially square metal case, and a pressure-resistance conversion element or other pressure-sensitive element detection portion are provided at four corners. The pressure sensor, the actuator rubber that pressurizes the upper surface of the pressure sensor as appropriate, the specific frame that assembles the key top movably up and down, and the key top that is assembled to this specific frame always move upward due to the elastic restoring force. In a specific key switch that also has a pointing function composed of an urging click rubber, a preload spring formed by a leaf spring is installed on the upper surface of the specific frame when the key top is attached to the specific frame. The feature is that the preload spring is installed so that the upper surface of the preload spring is pressed by a spring pressing piece that is erected from the metal case.

[0008]

[Action]

 Based on such a configuration, according to the present invention, the pressure-sensitive element of the pressure sensor can be used within an appropriate range in which the amount of change in resistance value with respect to the pressing force applied to the pressure sensor built into the key switch is stable. By applying a predetermined pressing force in advance, the amount of change in resistance value is small even with a slight pressing force, and the pointing function operates according to the difference in resistance value with respect to the change in applied pressing force. It is possible to accurately control the moving direction of the cursor position displayed above.

[0009]

【Example】

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

FIG. 1 is a sectional view showing a key switch structure according to an embodiment of the present invention. 2 is a sectional view taken along line 2-2 of FIG.

That is, the specific key switch 1 also having a pointing function has a key top 2 made of a synthetic resin molded product, a substantially square metal case 3, and a pressure sensing element such as a pressure-resistance conversion element. The pressure sensor 4 provided at the corner, the actuator rubber 5 that appropriately pressurizes the four corners of the upper surface of the pressure sensor 4, the specific frame 6 to which the key top 2 is vertically movable, and the specific frame 6 are attached. The key top 2 is composed of a click rubber 7 that always urges the key top 2 in the upward direction by the elastic restoring force.

Further, a cylindrical boss 2a is integrally projectingly provided in the central portion of the back surface of the key top 2, and leg portions 2b, 2b having engaging projections are provided on the front and rear sides or the left and right sides of the boss 2a. Are projected integrally. The boss 2a of the key top 2 is assembled to the boss receiving portion 6a of the specific frame 6, and the leg portion 2b of the key top 2 is engaged with the engaging portion 6b of the specific frame 6 to prevent the key frame from coming off. .

On the other hand, the pre-load spring 12 for pressurizing the pressure sensor 4 installed on the upper surface of the metal case 3 with a predetermined pressing force in the state where the specific key switch 1 is assembled is a leaf spring. It is molded by. The preload spring 12 is, for example, as shown in FIG. 3, a sensitive element provided at four corners of the pressure sensor 4 in a front and rear direction of a single plate having a window 12a mounted on the upper surface of the specific frame 6. It is formed by integrally bending a pressing piece 12b that uniformly presses.

The preload spring 12 is installed on the upper surface of the specific frame 6 when the specific key switch 1 is assembled, and the preload spring 12 is installed before the key top 2 is mounted on the specific frame 6. It is installed on the upper surface of the specific frame 6, and as shown in FIG. 2, the upper surface of the preload spring 12 is assembled in a state of being pressed by the spring pressing piece 3 a standing from the metal case 3.

FIG. 4 is a perspective view showing another embodiment of the preload spring according to the present invention. In this case, the preload spring 13 is provided on the upper left and right of the specific frame 6 when the specific key switch 1 is assembled. Each is installed. The shape of the preload spring may be any other shape, and the means for fixing the preload spring is not limited to the embodiment, and can be appropriately set according to the shape of the preload spring. .

In the embodiment of the present invention, four sensors 4 are used, but three or more sensors 4 may be provided, and the sensors 4 are provided at the corners of the upper surface of the metal case 3, but not only at the corners but also at the periphery of the upper surface. May be provided.

[0017]

[Effect of device]

 As described in detail above, the special key switch having the pointing function according to the present invention can be applied with a slight pressing force by applying a predetermined pressing force to the pressure sensor having the pressure-resistance conversion element in advance. However, the amount of change in resistance value due to the pressure sensor is small, and the pointing function is activated according to the difference in resistance value with respect to the change in applied pressing force. Therefore, when performing a pointing operation with a specific key switch, press the key top of the specific key switch to turn on the switch function, and change the direction of the pressing force on the upper surface of the key top. The resistance value at the pressed position of the pressure sensor equipped with the element changes, and the pointing function operates according to the difference in this change in the resistance value to accurately and quickly move the cursor position displayed on the display. Can be controlled.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a key switch structure according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a perspective view showing an embodiment of a preload spring according to the present invention.

FIG. 4 is a perspective view showing another embodiment of the preload spring according to the present invention.

FIG. 5 is a cross-sectional view showing a conventional key switch structure.

FIG. 6 is a characteristic diagram showing a relationship between a pressing force and a resistance value with respect to a pressure sensitive element built in a key switch.

[Explanation of symbols]

 1 Specific Key Switch 2 Key Top 3 Metal Case 3a Spring Holding Piece 4 Pressure Sensor 5 Actuator Rubber 6 Specific Frame 7 Click Rubber 12 Preload Spring

Claims (1)

[Scope of utility model registration request] 1. A key top made of a resin molded product, a substantially square metal case, a pressure sensor having a detection portion for a pressure sensitive element such as a pressure-resistance conversion element, and an actuator for appropriately pressing the upper surface of the pressure sensor. A pointing function composed of a mule, a specific frame that movably attaches the key top up and down, and a click rubber that constantly urges the key top attached to this specific frame upward by elastic restoring force. In the special key switch that also has a function, when mounting the key top to a specific frame, a preload spring formed by a leaf spring is installed on the upper surface of the specific frame, and the upper surface of the preload spring is erected from the metal case. The preload structure of the pressure-sensitive element built into the key switch, which is characterized in that it is installed so as to be pressed by.