JPH08190455A - Coordinate input device - Google Patents

Abstract

PURPOSE: To provide a coordinate input device which eliminates a slip of a rotated sphere and accurately transmits its rotation to a rotary shaft. CONSTITUTION: This coordinate input device has the rotated sphere 2 which is put in a substrate 1 and a lid body and partially projects from an opening 13, a couple of rotary shafts having code plates 7 and 8 which rotate associatively with the rotation of this rotated sphere 2 and have mutual axial directions in orthogonal relation, a light emitting element and a light receiving element which are arranged opposite to each other across those code plates 7 and 8, pivot bearings 15 and 16 on which the rotary shafts are pivoted while their axes are allowed to deflect, and a spring member 31 which energizes the rotary shafts toward the rotated sphere 2, and the spring member 31 has both its end parts 31a and 31b bent slantingly so as to energize the rotary shafts 3 and 4 toward the center part of the rotated sphere 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device which is provided in a display device such as a CRT display and whose rotation angle detecting means is an optical reading type.

[0002]

2. Description of the Related Art As a coordinate input device for inputting coordinate positions in the XY directions, a coordinate input device using a rotating ball is widely adopted for controlling a cursor position and inputting a figure. This coordinate input device rotatably accommodates a rotating ball in a casing having an opening so that a part thereof protrudes from the opening, and rotates in conjunction with the rotation of the rotating ball in the casing so as to rotate in the axial direction of each other. Are orthogonal to each other and have a pair of rotating shafts each having a code plate attached thereto, and a light emitting element and a light receiving element for optically detecting the rotating angle of the code plate. As the X-coordinate component and the Y-coordinate component of the rotating ball, and the detection signals are input to the display device.

In the coordinate input device constructed as described above, it is necessary to secure some clearance between the opening of the casing and the rotating ball protruding from the opening so that the rotating ball can smoothly rotate. If an excessive operating force is applied to the rotating balls during starting, especially at the time of starting, the rotating balls are likely to be displaced within this clearance range, and a strong force is applied to the rotating shaft and the bearings that support these rotating shafts. However, there is a problem that the rotary shaft may be plastically deformed. In order to improve this, it has been proposed to increase the mechanical strength by making each rotary shaft thicker, but in that case, the bearings and the like must also be increased, and the coordinate input device can be made smaller and cost-effective. Will be hindered.

Therefore, the present applicant has proposed a coordinate input device in which these disadvantages are improved in Japanese Patent Application No. 3-66015 filed previously. The coordinate input device will be described in more detail by taking the preceding example as an example. FIG. 5 is a plan view showing the internal structure of the coordinate input device, and FIG. 6 is a side view showing a part thereof in cross section.

The substrate 1 has a rotatable sphere 2 made of steel balls or the like.
Is rotatably housed, and a pair of rotating shafts 3 and 4 are arranged in the rotated sphere 2 such that their axial directions are orthogonal to each other. The rotating shafts 3 and 4 are provided with rollers 5 and 6 in contact with the rotated sphere 2 at their intermediate portions, and cord plates 7 and 8 having slits (not shown) at equal intervals at their one ends. ing. Further, the light emitting element 9 and the light receiving element 10 are arranged so as to sandwich the code plate 7, and the light emitting element 11 and the light receiving element 12 are arranged so as to face the code plate 8 in the same manner. These constituent members have openings 1 for projecting a part of the rotated sphere 2 on the upper surface.
It is covered by fitting the lid 14 on which the substrate 3 is formed to the substrate 1. Therefore, when the rotated sphere 2 that protrudes slightly from the opening 13 is rotated in an arbitrary direction by a manual operation,
The rotating shafts 3 and 4 interlock with the rotation of the rotated sphere 2 to rotate in predetermined directions. Since the rotation of the rotary shafts 3 and 4 rotates the code plates 7 and 8, the rotation angles of the rotary shafts 3 and 4 are detected by the light emitting elements 9 and 11 and the light receiving elements 10 and 12, respectively. The corners can be removed individually. The detection signals of the rotation angles of the rotary shafts 3 and 4 thus obtained are input to a display device (not shown) as the X coordinate component and the Y coordinate component of the rotated sphere 2.

In the above-mentioned prior art example, the pivot bearings 15 made of synthetic resin having high abrasion resistance are formed so that the rotary shafts 3 and 4 rotatably sandwich the portions near the code plates 7 and 8. , 16 are respectively pivotally supported. The ends of the rotary shafts 3 and 4 opposite to the cord plates 7 and 8 are the substrate 1
While being mounted on the jetty portions 17 and 18 formed above, it is engaged with the linear end portions 19a and 19b of the torsion coil spring 19 so as to be constantly urged toward the rotated sphere 2. . Therefore, these rotary shafts 3 and 4 not only rotate in the circumferential direction in conjunction with the rotation of the rotated sphere 2, but also the jetty 17, with the pivot bearings 15 and 16 as swing centers.
Shaking of the axis of sliding on 18 is allowed.
As a result, when an excessive operating force is applied to the rotated sphere 2 during operation, the rotary shafts 3 and 4 swing the axes while pushing the terminal portions 19a and 19b of the torsion coil spring 19, respectively. Therefore, the external force applied to each of the rotating shafts 3 and 4 from the rotated sphere 2 is moderated, and there is no fear of plastic deformation even if the rotating shafts 3 and 4 are made thicker to increase the mechanical strength. Reference numeral 20 denotes a support sphere having a high hardness such as ruby, which is arranged at three positions on the substrate 1, and the rotated sphere 2 is mounted on these support spheres 20 to support at three points.

[0007]

However, in the above coordinate input device, as shown in FIG. 7 for explaining the vector of the roller 5 with respect to the rotated sphere 2, the roller 5 is the same as the rotated sphere 2. The direction of the urging force which is in contact with the lower side and is applied to the roller 5 by the torsion coil spring 19 is the F1 direction parallel to the surface of the substrate 1, and therefore this F1 causes the rotation of the rotated sphere 2 to the roller 5. It is decomposed into f1 which is the frictional force to be transmitted and f2 other than that. This force of f2 works to prevent the rotation of the roller 5, resulting in the slip of the rotated sphere 2 being promoted.
May not be accurately transmitted to the roller 5.

A first object of the present invention is that the spring pressure of the spring member serves as a frictional force between the rotated sphere and the roller, the contact between the rotating shaft and the rotated sphere is reliably held, and the slip of the rotated sphere is prevented. An object of the present invention is to provide a coordinate input device that can press and accurately transmit its rotation to a rotation axis.

A second object of the present invention is to rotate the spring pressure of the spring member by simply bending and bending both ends of the spring member and engaging the bent portion with the rotary shaft. It is an object of the present invention to provide a coordinate input device that can act only as a frictional force between a sphere and a roller.

[0010]

A first object of the present invention is to provide a casing having an opening, a rotated sphere housed in the casing and a part of which projects from the opening, and the rotation of the rotated sphere. A pair of rotating shafts which are rotated by each other and whose axial directions are orthogonal to each other, code plates respectively integrated with these rotating shafts, and a light emitting element and a light receiving element which are arranged to face each other through these code plates, This is achieved by a first means that includes a pivot bearing that supports each of the rotating shafts while allowing the axis of the rotating shaft to swing, and a spring member that urges the rotating shafts toward the center of the rotated sphere. .

The second object is, in the first means,
This is achieved by the second means in which the portion of the spring member that comes into contact with the rotary shaft is bent in an oblique direction.

[0012]

In the first means, even if the rotating shaft receives a strong force from the rotated sphere and oscillates the axis while pushing the spring member, the rotating shaft causes the rotating shaft to move to the center of the rotated sphere. Since it is always urged in the direction, the spring pressure of the spring member becomes a frictional force between the rotating sphere and the roller, the contact between the rotating shaft and the rotating sphere is surely held, and the slip of the rotating sphere is suppressed. You can

In the second means, both ends of the spring member are bent in an oblique direction and the spring pressure of the spring member is applied by a simple structure in which the bent parts are engaged with the rotary shaft. It can act only as a frictional force between the rotating sphere and the roller.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing only a main part of an embodiment of the present invention, FIG. 2 is a side view thereof, FIGS. 3 (a), 3 (b) and 3 (c) are front views of a spring member, and FIG. FIG. 6 is a diagram for explaining a vector of a roller with respect to a rotated sphere in one example. The constituent elements that are substantially the same as those of the conventional example described above are designated by the same reference numerals, and detailed description thereof will be omitted.

The spring member 31 in this embodiment is shown in FIG.
As shown in (a), (b) and (c), the coil portion 31c and the both end portions 31a and 31b of the coil portion 31c are formed of a torsion coil spring which is biased in a direction away from each other.
The edges a and 31b are bent at an angle of approximately 90 ° and are bent obliquely so as to approach each other. In this embodiment, the bending angle in the oblique direction is 60 °, but this angle is such that the biasing force F2 is directed toward the center of the rotated sphere depending on the difference in the height position of the rollers 5, 6 with respect to the rotated sphere. Can be set appropriately. In addition, this spring member 31
1 is mounted on the substrate 1 with the bent ends 31a and 31b facing downward, as shown in FIGS. 1 and 2, and is on the side opposite to the code plates 7 and 8 of the rotating shafts 3 and 4. Are engaged with each other, and the rollers 5 and 6 of the rotating shafts 3 and 4 act so as to elastically press the rotated sphere 2. In the embodiment having such a configuration, the spring member 31
Since both end portions 31a and 31b of the roller are bent in an oblique direction so as to approach each other, and the rotating shafts 3 and 4 are engaged with the inside thereof, the biasing force to the rollers 5 and 6 in an obliquely upward direction, that is, As shown in FIG. 4, the urging force F2 is applied to the center of the rotated sphere 2. This urging force F2
The direction of is equivalent to the direction of f1 which is a frictional force transmitting the rotation of the rotated sphere 2 to the roller 5 in FIG. Therefore, the spring pressure of the spring member 31 is consumed as a frictional force between the rotated sphere 2 and the roller 5, and the occurrence of slip of the rotated sphere 2 can be suppressed as much as possible. In addition, the spring member 31
Both ends of each are bent in an oblique direction and the bent portions are engaged with the rotating shaft, so that the spring pressure of the spring member 31 acts only as a frictional force between the rotated sphere 2 and the roller 5. Can be made.

In the above embodiment, the support portion 32 having a spherical inner surface and rotatably holding the rotated sphere 2 is provided on the substrate 1, and the support sphere 20 of the conventional example is omitted. The upper surface of the support 32 is not shown,
It is covered with a lid 14 having an opening 13 similar to that of the conventional example. 33 is a spring member 31 protruding from the lower surface of the support portion 32.
It is a holding pin of the coil portion 31c.

The light emitting elements 9 and 11 and the light receiving element 10,
Although not shown in the figure, 12 and the like are, of course, arranged in the same manner as the conventional example. Further, in the above embodiment, 1
Although two rotating shafts are pressed and supported by one spring member 31, a spring member may be provided for each rotating shaft, or a spring member other than the torsion coil spring may be used.

[0018]

According to the first aspect of the present invention, even if the rotating shaft receives a strong force from the rotated sphere and oscillates the axis line while pushing the spring member, the rotating shaft causes the rotating shaft of the rotated sphere to move. Since it is always biased toward the center, the spring pressure of the spring member becomes a frictional force between the rotated sphere and the roller,
The contact between the rotating shaft and the rotated sphere is reliably maintained, the slip of the rotated sphere can be suppressed, and the rotation can be accurately transmitted to the rotating shaft.

According to the second aspect of the present invention, both ends of the spring member are bent obliquely and the spring pressure of the spring member is applied by a simple structure in which the bent parts are engaged with the rotary shaft. It can act only as a frictional force between the rotating sphere and the roller.

[Brief description of drawings]

FIG. 1 is a plan view showing only a main part of an embodiment of a coordinate input device of the present invention.

FIG. 2 is a side view thereof.

3 (a), (b) and (c) are a front view, a side view and a bottom view showing the spring member.

FIG. 4 is a diagram for explaining a roller vector with respect to a rotated sphere in an embodiment of the coordinate input device of the present invention.

FIG. 5 is a plan view showing an internal structure of an example of a conventional coordinate input device.

FIG. 6 is a side view showing a part thereof in cross section.

FIG. 7 is a diagram for explaining a vector of a roller with respect to a rotated sphere.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 substrate 2 rotated sphere 3,4 rotating shaft 5,6 roller 7,8 code plate 9,11 light emitting element 10,12 light receiving element 13 opening 14 casing 15,16 pivot bearing 31 spring member 31a, 31b end portion

Claims (2)

[Claims] 1. A casing having an opening, a rotated sphere housed in the casing and a part of which protrudes from the opening, and rotating in association with the rotation of the rotated sphere so that their axial directions are orthogonal to each other. A pair of rotating shafts, code plates respectively integrated with these rotating shafts, a light emitting element and a light receiving element which are arranged to face each other via these code plates, and each of the rotating shafts allows deflection of its axis. A coordinate input device, comprising: a pivot bearing that axially supports the rotating shaft; and a spring member that biases the rotating shaft toward the center of the rotated sphere. 2. The coordinate input device according to claim 1, wherein a portion of the spring member that comes into contact with the rotary shaft is bent in an oblique direction.