JPH0894671A - Cross coil-type movement - Google Patents

Abstract

PURPOSE: To provide a cross-coil type movement which is low-cost, superior in indicating properties and easily applicable to many specifications. CONSTITUTION: An upper bobbin 1a is meshed with a lower bobbin 1b thereby to form a bobbin 1. A disc-like magnet rotor 2 having a rotary shaft 2a at the central part thereof is rotatably arranged inside the bobbin 1. A peripheral edge part of the magnet rotor 2 is magnetized. A plurality of coils 3 are wound outside the bobbin 1 to intersect each other. A hole 11 for inserting a steel ball 12 is formed at a position in the vicinity of an outer peripheral part of the bobbin 1 except where the coils 3 are wound. The steel ball 12 is inserted in the hole 11, so that an indicator is returned to zero by the attraction force between the magnet rotor 2 and the steel ball 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross coil type movement used as a movement of an instrument used in a vehicle or the like, and more particularly to a cross coil type movement characterized by a zero-reset structure.

[0002]

2. Description of the Related Art Conventionally, a cross coil type movement has been used as a type of movement of measuring instruments used in vehicles and the like. The cross coil type movement is usually
A magnet rotor is rotatably arranged inside a bobbin in which an upper bobbin and a lower bobbin are fitted together, and coils are wound on the bobbin so as to intersect each other. Then, a current that changes according to the measurement amount is applied to the wound coils to rotate the magnet rotor in the direction of the synthetic magnetic field of the magnetic fields generated in the respective coils, and is attached to the rotating shaft of the magnet rotor. The pointer is used to display the measured amount.

Therefore, unless a rotating force for returning the rotating shaft, that is, the pointer, is applied to the rotating shaft by some method, the magnetic field generated in the coil when the power is turned off becomes zero. , The position where the pointer is fixed is unstable. Therefore, except for the needle-positioning type, a cross-coil movement is generally equipped with a zeroing device that acts to return the pointer to the zero position.

2 (a) and 2 (b) show an example of a cross-coil type movement to which a zeroing device is attached. FIG. 2 (a) is a sectional view seen from the front, and FIG. 2 (b) is a bottom view. It is a figure. As shown in the figure, in this cross-coil type movement, a magnet rotor 2 is arranged inside a bobbin 1 formed by fitting an upper bobbin 1a and a lower bobbin 1b. The magnet rotor 2 is provided with a disk-shaped magnet 2b having a pair of N and S poles magnetized on its peripheral edge and a rotating shaft 2a at the center, and the upper portion of the rotating shaft 2a is provided on the upper bobbin 1a. The lower part of the rotary shaft 2a is rotatably supported by the bearing portion 1bb of the lower bobbin 1b.

A plurality of coils 3 are provided outside the bobbin 1.
Are crossed and wound, and a drive current that changes in accordance with the measured amount is passed through the coil 3 to rotate the magnet rotor 2 in the direction of the combined magnetic field of the magnetic fields generated in the respective coils 3. The measuring amount is displayed on a dial (not shown) by means of a pointer (not shown) attached to the rotary shaft 2a of No. 2. Reference numeral 7 in the drawing is a mounting shaft which also serves as a terminal for supplying a drive current to the coil. On the other hand, a plurality of circular holes 4 are provided on the lower surface of the lower bobbin 1b as a zeroing device for returning the pointer to the zero position when the current for driving the movement is turned off. A disk-shaped magnet 5 is fitted in a predetermined hole 4 inside. The position of the predetermined hole 4 is determined by the positional relationship between the instrument and the dial in which this movement is used.

In addition to the zero-reducing device using such a magnet, many zero-removing devices using a mustache dance are also used. For example, as shown in FIG. 3, one end of the mustache 6 is fixed to the rotating shaft 2a of the magnet rotor, the other end is fixed to the protrusion 1A of the bobbin 1 and the like. It is a thing. 3A is a perspective view and FIG. 3B is a sectional view taken along line BB in FIG. 3A. In these figures, the same parts as those in FIG. 2 are denoted by the same reference numerals. .

[0007]

However, the method using the beard total dance is costly and the rotational torque has a temperature characteristic, so that it is troublesome to adjust the indicator characteristic of the pointer. The method using a magnet is also costly, and there is also a problem that the indicating characteristics vary due to variations in magnetism. Further, as described above, there is a device in which the magnet 5 can be fitted into the predetermined hole 4 depending on the specifications of the instrument, but since the coil 3 must be set in advance before being wound, it is possible to comply with the specifications. There are many formats and it becomes complicated.

According to the present invention, the cost is low and the indicating characteristic is good,
Moreover, it aims to provide a cross-coil type movement that can easily cope with a large number of specifications.

[0009]

A cross-coil type movement according to the present invention is a disk shape having a peripheral portion magnetized in a bobbin formed by fitting an upper bobbin and a lower bobbin and having a rotation axis at the center. In a cross-coil type movement in which the magnet rotor is rotatably arranged and a plurality of coils are crossed and wound on the outside of the bobbin, magnetic force is applied at a position other than the position where the coil is wound near the outer periphery of the bobbin. A feature is that a hole for inserting a body is formed and a magnetic body is arranged in this hole.

Further, in this case, the hole is composed of a plurality of holes,
A magnetic material can be placed in any of these holes depending on the specifications.

In the above case, the magnetic body can be composed of steel balls or magnets, but steel balls are particularly preferable in terms of cost.

[0012]

According to the invention described in claim 1, a hole for inserting the magnetic body is formed at a position other than the position where the coil is wound near the outer peripheral portion of the bobbin, and the magnetic body is arranged in this hole. However, when the drive current corresponding to the measured amount is flowing through the coil, the attractive force of the combined magnetic field by the coil is stronger than the attractive force between the magnetic poles of the magnet rotor and the magnetic body. Point in the direction of the composite magnetic field of. Once the drive current is turned off, the combined magnetic field by the coil becomes zero, so the magnet rotor rotates and returns to zero due to the mutual attractive force between the magnetic pole and the magnetic body. In the case of this type of movement, if the magnetic body is made of steel balls as described in claim 3, the cost can be reduced as compared with the case of using a magnet.

According to the second aspect of the present invention, since a plurality of holes for inserting the magnetic body are formed near the outer peripheral portion of the bobbin, it is possible to decide which hole the magnetic body should be inserted in according to the specifications. Therefore, it is possible to meet various specifications. At that time, since the magnetic body can be inserted after the coil is wound, it is not necessary to manufacture a movement that matches the model of the instrument in advance, and it is possible to unify it to the same model. It can be done, and it also leads to cost reduction. Further, the magnetic body to be inserted may be a magnet or a steel ball as described in claims 3 and 4, but the steel ball is more advantageous in terms of cost.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In addition, the same or corresponding parts as those described in the related art are designated by the same reference numerals and the description thereof will be omitted. FIG. 1 shows an embodiment of the present invention.
(A) is a perspective view, (b) is sectional drawing by the AA line of (a). As shown in the figure, the upper bobbin 1a is provided with three cylindrical holes 11 on its upper surface.
Has a tip extending to a position facing the circumferential edge of the magnet rotor 2 disposed inside the bobbin 1. A steel ball 12, which is a spherical magnetic substance, is press-fitted into the tip of any of these holes 11.

The hole 11 into which the steel ball 12 is inserted depends on the specifications of the instrument, and when the drive current flowing through the coil 3 becomes zero or when the magnet rotor 2 is zeroed by the attraction force with the steel ball 12. In addition, the pointer attached to the rotary shaft 2a of the magnet rotor 2 is set at a position indicating the zero position of the dial. Of course, if the specification of the measuring instrument is fixed to one type from the beginning, the hole 11 may be only one place.

Further, since the positions of these holes 11 are provided at positions other than the position where the coil is wound, the magnetic material can be inserted after the coil is wound, and the measuring instrument can be installed in advance. Since it is not necessary to manufacture a movement that matches the format, it is possible to manufacture the movements of the same type, which leads to cost reduction. The steel ball 12 used here is a ball bearing steel ball for supporting the rotary shaft 2a of the magnet rotor 2. This steel ball for a ball bearing has a good accuracy in outer diameter dimension and is not magnetized, so that it is possible to obtain stable zero-reset characteristics and indicating characteristics.
Also, you don't have to use the costly beard full dance,
The cost of the movement as a whole can be reduced, and the number of man-hours for assembling can be reduced because it is not necessary to adjust the indication of the pointer due to the temperature characteristics of the mustache.

In this embodiment, the steel ball 12 is used as the spherical magnetic body, but a spherical magnet may be inserted instead of the steel ball 12 although the cost is slightly increased. In this case, it is necessary to pay attention to the direction of the magnetic pole.

[0018]

As described above, the cross-coil type movement according to the present invention has the advantages that the manufacturing cost is low, the indicating characteristic is good, and a large number of specifications can be easily met.

[Brief description of drawings]

1 shows an embodiment of the present invention, (a) is a perspective view,
(B) is sectional drawing by the AA line of (a).

2A and 2B show a conventional cross-coil type movement using a magnet as a zeroing device, in which FIG. 2A is a sectional view seen from the front, and FIG. 2B is a bottom view.

3A and 3B also show a conventional cross-coil type movement using a mustache full dance as a zeroing device, FIG. 3A is a perspective view, and FIG. 3B is a sectional view taken along line BB in FIG. 3A.

[Explanation of symbols]

 1 bobbin 1a upper bobbin 1b lower bobbin 2 magnet rotor 2a rotating shaft 2b disk-shaped magnet 3 coil 11 hole 12 steel ball

Claims (4)

[Claims] 1. A bobbin, which is formed by fitting an upper bobbin and a lower bobbin, has a disk-shaped magnet rotor rotatably arranged at its peripheral portion and having a rotating shaft at its center, and is outside the bobbin. In a cross-coil type movement in which a plurality of coils are wound by crossing each other, a hole for inserting a magnetic body is formed at a position other than the position where the coil is wound near the outer peripheral portion of the bobbin. A cross-coil type movement characterized by arranging a magnetic material in the hole. 2. The cross-coil type movement according to claim 1, wherein the hole is composed of a plurality of holes, and a magnetic material is arranged in any of the holes according to the specifications. 3. The cross coil type movement according to claim 1, wherein the magnetic body is a steel ball. 4. The cross coil type movement according to claim 1, wherein the magnetic body is a magnet.