JP2000259341A - Pointing stick - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pointing stick which can faultlessly and easily detect a (z) direction in the same way as (x) and (y) directions, which has less dispersion in detection sensitivity and whose manufacture cost can be reduced. SOLUTION: The pointing stick is equipped with a polygonal or circular ceramic substrate 21 where an electrode land part is installed at an outer peripheral part, a post 30 is arranged in a central part, and also four resistors are installed between the outer peripheral part and the central part at equal intervals with the post 30 as the center and a base 31 on which the substrate 21 is loaded. The substrate 21 is electrically connected to the base 31 with soldering in the electrode land 24 of the outer peripheral part and is fixed so that a gap 33 is provided between the substrate 21 and the base 31 with soldering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointing stick, and more particularly to a pointing stick suitable for moving a position of a cursor on a display screen of a notebook personal computer or the like and performing various control operations.

[0002]

2. Description of the Related Art A pointing stick is a component used as a signal input device in information processing equipment such as a notebook personal computer and a game machine.
A signal can be input by pressing with a finger in the direction or the z direction. In a notebook computer or the like, a similar signal input operation can be performed by operating a pointing stick instead of moving the mouse or clicking the button. In game machines and the like, a pointing stick has long been used as a joystick for operating a display screen.

[0003] Such a pointing stick is
Conventionally, a structure as shown in FIG. 3 has been generally used (for example, see Japanese Patent Application Laid-Open No. Hei 10-222295). That is, a thick film or thin film resistor 12 is provided under the elongated prism 10.
Are formed on the four surfaces, the base of the prism 10 is fixed to the hole of the printed wiring board with an adhesive or the like, and the resistor is connected to the printed wiring board 11 as a bridge circuit by soldering. The resistor 12 provided below the prism 10 operates in the same manner as the strain gauge, and generates a compressive force in a direction in which the prism is bent, a resistance value decreases, and a tensile force acts in a direction in which the prism is pulled. And the resistance increases. Therefore, by arranging the resistors on the four surfaces of the prism, x acting on the prism is obtained.
Signals of the pressing force in four directions of +, x-, y +, y- can be detected. Also, by pressing the head of the prism downward, a compressive force acts equally on the resistor 12 on each surface of the prism,
As a result, the resistance value of each resistor uniformly decreases. Therefore, in principle, distortion in the z direction can be detected, and this can be used in the same manner as a mouse click operation.

[0004] However, the above-mentioned pointing stick has the following problems. First, as described above, the pressing force in the z direction can be detected in principle by pressing the head of the pointing stick downward. However, since no bending force is generated in the prism in the z direction, the compressive force or the tensile force on the resistor is x, y
The signal output is extremely weak compared to the operation of the pointing stick in the direction.

[0005] Second, a prism 10 is provided through the printed wiring board 11, and the electrodes of the resistor 12 are connected to the printed wiring board 1.
Since it is fixed to the wiring portion 1 by soldering, the pressure applied to the prism 10 is directly applied to the soldered portion. Therefore, when the pressing force is repeatedly applied to the prism 10, the soldered portion gradually deteriorates, and the prism may eventually fall out without being able to withstand the external force. That is, there was a problem in durability. Further, since the resistor portions provided on each surface of the prism are used by being inserted into the openings of the printed wiring board, there is a problem that the resistor portions are easily mechanically damaged particularly at the time of the insertion. .

Third, the pointing stick shown in FIG. 3 has a problem that the manufacturing process is complicated and it is difficult to reduce the manufacturing cost. That is, since the resistors are formed on the four faces of the prism, screen printing must be performed when each resistor is made of a thick film for each face, and the operation is extremely complicated. For this reason, it is difficult to reduce the manufacturing cost.

In view of the above problems, a pointing device has been proposed in which an operation section is provided at the center of a flat elastic plate, a resistance detecting element is provided around the operation section, and the periphery of the elastic plate is fixed at four places. (For example, Japanese Patent Application Laid-Open No. 7-1746)
No. 46). According to such a pointing device,
By applying a pressing force to the operation part at the center of the elastic plate, the elastic plate is deformed to bend and a resistance value change occurs in the resistance detecting element. By calculating and outputting this output, the direction and magnitude of the force of the operation part are obtained. Can be detected. However, such a pointing device also requires wiring connection between, for example, a resistance detecting element disposed on an elastic plate provided with a glass enamel coating and an external circuit for extracting the output, and thus the manufacturing of the pointing device itself is not always easy. It was not something.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and enables reliable and easy detection in the z-direction as in the x- and y-directions. It is an object of the present invention to provide a pointing stick capable of reducing the manufacturing cost.

[0009]

According to a first aspect of the present invention, an electrode land portion is provided on an outer peripheral portion, a post is provided on a central portion, and a center of the post is provided between the outer peripheral portion and the central portion. A polygonal or circular ceramic substrate provided with four resistors at equal intervals, and a base on which the substrate is mounted, wherein the substrate is soldered to the base at electrode lands on the outer periphery thereof. A pointing stick which is electrically connected and fixed so as to provide a space between the substrate and the base by the soldering.

According to the present invention, a thin substrate having a post at the center is provided with a resistor between the center and the outer periphery, and an electrode land is provided at the periphery of the substrate. The part is connected and fixed to a land part of a base (for example, a printed wiring board) by soldering. By providing this solder connection with a certain thickness, it is possible to provide a gap on the back side of the substrate between the solder connection and the surface of the base.
Therefore, the thin substrate is firmly supported by soldering to the surface of the base at the electrode lands on the outer periphery, and the portion of the substrate on which the resistor is disposed is applied with a pressing force to the post, so that the outer peripheral portion is It can be easily displaced (bent) using the soldered portion as a fulcrum. For this reason, post is x,
If the post is pressed in the y and z directions, a large compressive and tensile force is applied to the resistor disposed on the substrate by the leverage principle, even if the amount of displacement of the post in the operation section is small. Thereby, high detection sensitivity is obtained in the x, y, and z directions. Then, the solder connection portion serves as a fulcrum for supporting the outer peripheral portion of the substrate, and even if the post is pressed in the z direction, the pressing force is dispersed by bending deformation of the substrate, so that all of the pressing force is directly applied to the solder connection portion. No action is taken, which results in high durability.

The invention according to claim 2 is the pointing stick, wherein the substrate is octagonal, and eight electrode lands are provided on an outer peripheral portion thereof. Thus, the substrate is electrically connected and mechanically supported by the solder connection portions having a certain thickness with respect to the base, with the lands disposed at eight locations on the outer peripheral portion thereof. Eight electrode lands are connected to both ends of the four resistors by wiring, and the substrate can be supported in a well-balanced manner by dispersing the pressing force applied to the post with the substrate as a fulcrum of its bending. Thereby, good detection sensitivity can be obtained in the x, y, and z directions. If the electrode lands are supported at four locations, the dispersion of the pressing force applied to the post is not sufficient, and the operation may be unstable. Then, it is easy to fix the electrode land portion of the substrate to a base (for example, a printed wiring board) at a uniform height by soldering with a surface mounting technology, and the structure of such a pointing stick has been matured at present. Thick film technology can be used, and it can be manufactured easily and at low manufacturing cost.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is an elevational view of a pointing stick according to an embodiment of the present invention. FIG. 2 is a diagram showing a structure on the back side of a substrate. It is shown.

A post 30 is provided at the center of the octagonal thin alumina substrate 21 on the surface side. The post 30 has a thick portion 30 a at the lower end thereof, and the lower end surface is fixed to the center of the substrate 21 with an adhesive. still,
In this embodiment, the post 30 has the thick portion 30a, but may have the same size from the upper end to the lower end without the thick portion. Further, the post 30 may be a prism or a cylinder. On the back side of the substrate 21, a thick film resistor 22 made of four RuO ₂ is arranged. The resistor 22 is connected to the bridge by an AgPd thick film conductive layer 23 so as to be connectable as a bridge circuit. Are provided with electrode lands 24 connected to the printed wiring board. Except for the electrode lands 24, the rear surface of the substrate is covered with a protective film (not shown) to protect the resistor 22 and the conductive layer 23.

The resistor 22 is connected by a wiring electrode 23, and is arranged between the center and the outer periphery of the substrate. As shown, eight electrode lands 24 are provided radially from the center of the substrate on the outer peripheral portion. This electrode land 24
Is fixed to a base (printed wiring board) 31 by solder connection, and the back surface of the substrate floats from the surface of the printed wiring board.
That is, the electrode lands 24 are provided at eight locations on the periphery of the substrate 21 and are fixed to the wiring lands of the printed wiring board by the solder 32 so that the respective electrode lands have the same height. The thickness t of the soldered portion is about 0.1 mm in this embodiment, and the back surface of the substrate 21 on which the resistor is disposed has a gap 33 that can bend between the back surface of the substrate 21 and the front surface of the printed wiring board 31. are doing.

The printed wiring board 31 has a built-in bridge type output circuit (not shown) connected to its land, and outputs a signal to the outside via a flat cable (not shown) or the like. The resistor 22 has such a characteristic that the resistance increases when the tensile force acts and expands, and decreases when the compressive force acts and contracts. When the resistor 22 expands and contracts, the balance of the resistor bridge circuit is lost and a potential difference occurs. This potential difference changes linearly in a certain range, and by amplifying the potential difference, a change in the pressing force applied to the post can be output as a signal.

Since the outer peripheral portion of the substrate is supported by the solder connecting portion 32 having a certain height, the solder connecting portion 32 becomes a fulcrum, and x,
By applying the pressing force in the y and z directions, a large compressive or tensile force can be applied to the resistor 22 provided substantially at the center between the central portion and the outer peripheral portion of the substrate. Therefore, it becomes possible to detect a change in distortion of the resistor 22 caused by pressing the post in the x, y, and z directions with good sensitivity. In order to obtain a large output by distorting the substrate the most, the longer the distance between the electrode land (fulcrum forming portion) 24 and the center of the substrate, the more easily the substrate is distorted and the larger the output.

The formation of such a fulcrum having a constant height can be easily performed by using the technique of soldering a surface mount component, and simultaneously achieving the fulcrum having a certain height and fixing as a strong connection terminal. Can be. In the case of this embodiment, the substrate 21 is held by eight points of support, so that a structure with a good balance of heights and a high bonding strength can be obtained. The connection of this board to the printed wiring board by soldering can be handled evenly by printing cream solder on the printed wiring board, mounting the board, and reflowing since the back side of the board can be treated as a surface mount component. Solder height and strong solder connection are obtained. At this time, the height of the fulcrum can be easily adjusted by the solder printing amount and the reflow condition.

According to the configuration of the present embodiment described in detail above,
The operation of the post 30 in the x, y, and z directions does not always generate a tensile stress in the solder connection portion 32, and a compressive or bending stress is generated at a rate similar to that of the tensile. This is very different from the conventional example of FIG. 3 which has a problem in durability, and has excellent durability. That is, according to the configuration of the conventional example shown in FIG. 3, even when the stick is operated in all directions of x, y and z, tensile stress mainly occurs in the solder connection portion (the lower end of the resistor 12), and the printed wiring board 11 According to the configuration of the present embodiment, a tensile stress in the peeling direction is not always generated, but a compressive or bending stress is appropriately applied to the solder connection portion 32 while the interface is easily separated at the interface with the resistor 12 and the resistor 12. Therefore, the solder connection portion 32 is excellent in durability without breakage due to interface peeling.

In this embodiment, a thick film resistor and a wiring layer connecting these and a land portion are formed by a thick film on the back surface side of the alumina substrate. However,
Of course, a thick film resistor may be arranged on the front surface side of the substrate and connected to the land portion on the rear surface side of the substrate via a through hole. Further, in the above-described embodiment, an example in which an octagonal substrate is used and eight electrode land portions are provided has been described. However, a circular substrate is used and eight or more electrode land portions are provided, and The substrate may be supported by solder connection. Thus, the pressing force applied to the post can be further dispersed, and the stability and durability of the pointing stick can be further increased.

[0020]

According to the present invention as described above,
Provided is a pointing stick that can provide sufficient output with respect to application of a pressing force of a post not only in the x and y directions but also in the z direction, has high stability and durability, and can be manufactured at low cost. Can be.

[Brief description of the drawings]

FIG. 1 is a front view of a pointing stick according to an embodiment of the present invention.

FIG. 2 is a view showing an arrangement of a resistor and an electrode wiring on the back surface of the substrate of FIG. 1;

FIG. 3 is a diagram showing a main part of a conventional pointing stick.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Substrate 22 Resistor 23 Electrode wiring (thick film conductive layer) 24 Electrode land part 30 Post 31 Printed wiring board (base) 32 Solder connection part 33 Air gap

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Atsumi Inukai 15-1 Naeshiro-cho, Mizuho-ku, Nagoya-shi, Aichi F-term in Brother Industries, Ltd. 5B020 BB10 CC12 DD03 DD58 HH22 5B087 AA02 AA07 AE00 BC02 BC12 BC19 BC22 BC26 BC33 DD03

Claims (2)

[Claims] 1. A polygon having an electrode land portion on an outer peripheral portion, a post at a central portion, and four resistors disposed at equal intervals around the post between the outer peripheral portion and the central portion. Or a circular ceramic substrate and a base on which the substrate is mounted, wherein the substrate is electrically connected to the base by soldering at electrode lands on an outer peripheral portion thereof, and the substrate and the base are connected to each other. A pointing stick, wherein the pointing stick is fixed so as to provide a gap therebetween by the soldering. 2. The pointing stick according to claim 1, wherein the substrate is octagonal and has eight electrode lands on an outer peripheral portion thereof.