JPH0634661A - Cross coil type indicator - Google Patents

Abstract

PURPOSE:To obtain a cross coil type indicator which is a multi-shaft type indicator so designed that a force of rotation of a rotor shaft is transmitted to a drive shaft and thereby a pointer fitted to the drive shaft is driven to rotate, and which can be manufactured inexpensively and easily with the number of components lessened. CONSTITUTION:Inside a cross coil prepared by winding round two coils on a coil bobbin 3 in directions of intersecting each other perpendicularly, a magnet rotor 5 rotating at a prescribed angle around a rotor shaft 6 in accordance with a resultant magnetic field of the magnetic fields generated by the coils by electrification thereof is disposed. A drive shaft 10 to which a drive gear 13 made to engage with an output gear 7 of the rotor shaft 6 is fitted and to the fore end part of which a pointer 14 is fitted is disposed rotatably in the vicinity of the rotor shaft 6, and a hair spring 16 for returning the pointer to a zero position in a state of each coil not being electrified is fixed to a hair spring fixing part 26 formed monolithically with the drive gear.

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 indicator, and more particularly to a multi-axis cross-coil type indicator for transmitting rotation of a rotor shaft of a magnet rotor to a drive shaft to drive a pointer.

[0002]

2. Description of the Related Art Generally, a current that changes in accordance with a measurement amount is applied to a pair of coils that generate mutually orthogonal magnetic fields, and a magnet rotor is rotated in the direction of a synthetic magnetic field of the magnetic fields generated by the pair of coils. In many cases, a cross-coil type in-vehicle indicating instrument that displays a measured amount by a pointer that rotates together with the magnet rotor is used. In recent years, it has been practiced to arrange a plurality of pointers close to each other inside a combination meter. In such a case, the drive shaft to which the pointers are attached is offset from the rotor shaft of the magnet rotor and separated. A multi-axis type indicating instrument has been developed.

FIG. 3 shows such a conventional multi-axis cross-coil type indicator instrument. The instrument movement 2 of the instrument unit 1 has a coil bobbin 3, and this coil bobbin 3 has a coil bobbin 3. The two coils 4 and 4 are wound so as to be orthogonal to each other. A disk-shaped magnet rotor 5 having an S pole and an N pole is rotatably disposed inside the coil bobbin 3, and a central portion of the magnet rotor 5 extends in the axial direction. A rotor shaft 6 is attached. Further, an output gear 7 is fixed to the upper portion of the rotor shaft 6.

A bearing recess 8 is formed in the center of the lower surface of the magnet rotor 5 housing portion of the coil bobbin 3. Inside the bearing recess 8, a braking force is applied to the rotor shaft 6 to apply rotor force to the rotor. The shaft 6 is filled with a filler (not shown) such as silicon for preventing unnecessary swinging. The magnet rotor 5 is freely rotatable about the rotor shaft 6 when the coils are not energized, and can be rotated by a predetermined angle by energizing the coils. .

In addition, on one side of the coil bobbin 3,
A bearing hole 9 extending in the vertical direction is formed, and a drive shaft 10 is rotatably arranged inside the bearing hole 9. The lower end of the drive shaft 10 is supported by a thrust bearing 11 embedded in the bottom of the bearing hole 9, and
The upper end of the drive shaft 10 is held by the bearing member 12 fitted in the upper end of the bearing hole 9 so as not to come off. A drive gear 13 meshed with the output gear 7 of the rotor shaft 6 is fixed to the drive shaft 10, and the tip end of the drive shaft 10 is located on the surface side of a dial (not shown). A pointer 14 is attached.

A drive gear 13 is attached to the drive shaft 10.
A mustache ball 15 is press-fitted in the vicinity of the lower side, and the other end of a mustache spring 16 whose one end is connected to the coil bobbin 3 side is fixed to this beard ball 15. Further, on the outer circumference of the coil bobbin 3, there is provided a magnetic shielding case 17 for shielding the magnetic field.
Are formed.

The instrument unit 1 is housed inside a combination meter (not shown), and the combination meter is attached to an instrument panel of a vehicle such as an automobile.

In the above-mentioned conventional indicating instrument, a predetermined current as a drive signal based on a predetermined measurement signal is supplied to each of the coils 4 so that the combined magnetic field of the magnetic fields generated by each of the coils 4 becomes The magnet rotor 5 is rotated by an angle corresponding to the measured amount. As a result, the rotor shaft 6 is rotationally driven, and the rotational force of the rotor shaft 6 is transmitted via the output gear 7 and the drive gear 13 to the drive shaft 1
When the drive shaft 10 is transmitted to 0 and the drive shaft 10 is rotationally driven, the pointer 14 is rotated on the dial to display a predetermined measurement amount.

When the coils 4 are no longer energized as in the case where the ignition switch of the automobile is turned off, the drive shaft 10 is rotated to a predetermined zero position by the urging force of the balance spring 16 and Pointer 14
Is returned to a predetermined zero position.

[0010]

However, in the above-mentioned conventional cross-coil type indicating instrument, the end portion of the hairspring main body 16 is fixed by the beard balls 15 press-fitted into the drive shaft 10.
Since it is held, it is indispensable to press-fit the beard balls 15 into the drive shaft 10. On the other hand, press-fitting the beard balls 15 into the drive shaft 10 requires a considerably large force.
It becomes difficult to press-fit such a beard ball 15, and since the beard ball 15 is required, the number of parts increases,
It is difficult to manufacture the instrument movement 2 and the cost increases.

The present invention has been made in view of the above points, and an object of the present invention is to provide a cross-coil type indicating instrument which can be manufactured inexpensively and easily with a reduced number of parts.

[0012]

In order to achieve the above object, a cross coil type indicator according to the present invention forms a cross coil by winding two coils around a coil bobbin in a direction orthogonal to each other. A magnet rotor is rotatably arranged around the rotor shaft inside, and a drive gear that meshes with an output gear provided on the rotor shaft is provided in the vicinity of the rotor shaft, and a pointer is attached to the tip. A drive shaft is rotatably arranged, and a hairspring that urges the pointer toward the zero position is attached to the drive shaft.
The magnet rotor is rotated by a predetermined angle according to the combined magnetic field of the magnetic fields generated by the energization of the coils, and the pointer is returned to the zero position by the balance spring without energizing the coils. In the cross coil type indicator to be operated, a bevel spring fixing portion to which one end of the beard spring is fixed is integrally formed with the drive gear.

[0013]

According to the present invention, the hairspring fixing portion to which one end of the hairspring is fixed is integrally formed with the drive gear that transmits the rotational force from the rotor shaft to the drive shaft. This eliminates the need for a beard ball to attach the hairspring to the drive shaft, which makes it possible to omit the press-fitting work for a beard ball, which was difficult in the past, and to reduce the number of parts, making the instrument movement inexpensive and easy. It can be manufactured.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. 1 and FIG. 1 and 2 show an embodiment of a cross-coil type indicating instrument according to the present invention. The instrument movement 2 of the instrument unit 1 includes a coil bobbin 3 formed by joining an upper bobbin 18 and a lower bobbin 19. And has this coil bobbin 3
Two coils (not shown) are wound around each other. A disk-shaped magnet rotor 5 having S and N poles is rotatably disposed inside the coil bobbin 3, and the magnet rotor 5 has an axially extending center portion. The rotor shaft 6 rotatably supported is attached to the bearing recesses 8 of the upper bobbin 18 and the lower bobbin 19. An output gear 7 forming a transmission mechanism is fixed to the rotor shaft 6, and by energizing the coils based on a predetermined measurement amount,
The magnet rotor 5 is rotationally driven to drive the rotor shaft 6
It is designed to rotate.

A cylindrical bearing member 20 is rotatably provided on one side of the upper bobbin 18 separately from the upper bobbin 18, and an inner bottom portion of the bearing member 20 is provided. The bearing recess 21 is formed. Further, inside the bearing member 20, a drive shaft 10 whose lower end is axially supported by the bearing recess 21 is rotatably driven. The drive shaft 10 includes an output gear 7 of the rotor shaft 6.
The drive gear 13 meshed with is fixed, and the gear ratio between the output gear 7 and the drive gear 13 is set to, for example, 1: 2. It is designed to rotate once.

A contact protrusion 22 extending in the radial direction is formed on the lower surface of the drive gear 13, and a predetermined portion of the drive gear 13 is provided on the bearing member 20 below the drive gear 13. Of the stopper 2 for preventing the rotation of the drive gear 13 by coming into contact with the contact projection 22 at the zero position of
3 is formed to project. Further, a braking ring 24 is formed integrally with the drive gear 13 on the inner side of the bearing member 20 of the drive shaft 10, and the braking ring 24 is attached to the drive shaft 10 inside the bearing member 20. Filling agent 25 such as silicon is applied to apply a braking force therethrough to prevent unnecessary vibration of drive shaft 10.

On the upper surface of the drive gear 13, a bevel spring fixing portion 26 which functions as a beard ball is provided at the center thereof.
Is integrally formed, and this mustache spring fixing portion 26
A slit 27 is formed in the. Then, the other end of the hairspring 16 having one end fixed to a beard holding portion 28 protruding from the lower surface of an outer cover 29 described later is engaged with the slit 27 and fixed by a predetermined means. With the biasing force of the balance spring 16, the drive shaft 10 is rotated until the contact protrusion 22 of the drive gear 13 contacts the stopper 23 in a state where the drive shaft 10 can freely rotate. Has become.

Further, an outer cover 29 is fitted over the upper bobbin 18 so as to cover the upper bobbin 18, and the outer cover 29 is provided at a position corresponding to the drive shaft 10 as described above. Bearing part 3 for supporting the upper part of the drive shaft 10
0 is formed. It should be noted that the outer cover 29 may be provided with a bearing portion that pivotally supports the upper portion of the rotor shaft 6.

A pointer 14 located on the front side of a dial (not shown) is attached to the upper end of the drive shaft 10. Further, below the coil bobbin 3, a magnetic shield case for blocking a magnetic field is attached. 17 is attached.

The instrument movement 2 having the above-mentioned structure is mounted on a hard printed wiring board 31 for converting a predetermined measurement signal into a drive signal, and the pointer 14 portion is provided on the back side of the dial of a combination meter (not shown). Is stored so as to be located on the front side of the dial, and the combination meter having the instrument movement 2 is attached to an instrument panel of a vehicle such as an automobile.

Next, the operation of this embodiment will be described.
In this embodiment, by applying a predetermined voltage as a drive signal based on a predetermined measurement signal to each of the coils, the magnet rotor 5 is measured according to the combined magnetic field of the magnetic fields generated by the coils. Rotate the angle corresponding to the amount. In this magnet rotor 5, one coil of the cross coil is Vcos θ, and the other coil is Vs.
By applying a voltage of inθ, it is rotated by a predetermined angle θ. In this case, in this embodiment, the gear ratio between the output gear 7 and the drive gear 13 is 1 :.
Since the rotor shaft 6 is formed in two, it is necessary to rotate the rotor shaft 6 twice in order to rotate the drive shaft 10 once, but by setting the angle θ in the range of 0 to 720 °,
The magnet rotor 5 can be rotated twice, and
By changing the applied voltage between the first rotation and the second rotation of the magnet rotor 5, the first rotation and the second rotation are distinguished.

The rotor shaft 6 is rotationally driven by the rotation of the magnet rotor 5, and the rotor shaft 6 is rotated.
Is transmitted to the drive shaft 10 via the output gear 7 and the drive gear 13, whereby the drive shaft 10 is rotated against the biasing force of the balance spring 16 and the pointer 14 is rotated on the dial. Then, the predetermined measurement amount is displayed. Also, turn off the ignition switch of the car.
When the coil is de-energized as in the case of the above, the drive shaft 1 is driven by the biasing force of the balance spring 16.
0 is rotated until the contact projection 22 contacts the stopper 23, and the pointer 14 is returned to a predetermined zero position.

At this time, in the present embodiment, the hairspring main body 16 is directly fixed to the hairspring main body fixing portion 26 formed integrally with the drive gear 13 and the beard balls as in the conventional case are omitted, so that the work is carried out. It is not necessary to press the beard balls into the drive shaft, which is difficult, the number of parts can be reduced, and the instrument movement 2 can be easily manufactured at low cost.

The lower end of the drive shaft 10 is supported by the bearing recess 21 of the bearing member 20, and the drive shaft 1
Since the upper part of 0 is pivotally supported by the bearing portion 30 of the outer cover 29 fitted to the upper part of the coil bobbin 3, the axial distance of the pivotal support portion of the drive shaft 10 becomes long, and the drive shaft 10
Of the rotor shaft 6 and the drive shaft 10 can be reliably positioned with respect to the rotor shaft 6, and the output gear 7 of the rotor shaft 6 and the drive gear 13 of the drive shaft 10 can be prevented. It is possible to improve the accuracy of meshing with.

Further, since the gear ratio between the output gear 7 and the drive gear 13 is formed to be 1: 2, even when the rotor shaft 6 is rotated with a small rotation torque, the pointer 14 having a relatively heavy weight is used. The mounted drive shaft 10 can be driven to rotate, and moreover, since the pointer 14 is attached to the drive shaft 10 and the rotor shaft 6 itself does not receive the weight in the axial direction by the pointer 14, the rotor shaft 6 Bearing recess 8
The friction loss is small and the weight hysteresis is small, and as a result, the rotation torque can be reduced together with the reduction gears 7 and 13. As a result, even when the magnet rotor 5 is driven with a small rotational torque to rotate the rotor shaft 6, the drive shaft 1 with the pointer 14 attached thereto
0 can be rotationally driven, the thickness dimension of the magnet rotor 5 can be made small, and the instrument movement 2 can be made thin.

The present invention is not limited to the above-described embodiment, but can be variously modified as needed. A beard holding portion is provided on the upper surface of the upper bobbin 18. The other end of the balance spring 16 having one end fixed to the drive gear 13 may be fixed to the holding part.

[0027]

As described above, the cross coil type indicator according to the present invention has a hairspring fixing part in which one end of the hairspring is fixed to a drive gear for transmitting the rotational force from the rotor shaft to the drive shaft. Since it was designed to be integrally formed,
As in the past, there is no need for a beard ball to attach the hairspring to the drive shaft. As a result, it is possible to omit the press-fitting work of the beard ball, which was difficult in the past, and to reduce the number of parts. It is possible to produce the resin inexpensively and easily.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a cross coil type indicator according to the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a vertical cross-sectional view showing a conventional cross coil type indicating instrument.

[Explanation of symbols]

 1 instrument unit 2 instrument movement 3 coil bobbin 5 magnet rotor 6 rotor shaft 7 output gear 10 drive shaft 13 drive gear 14 pointer 15 beard ball 16 beard spring 18 upper bobbin 19 lower bobbin 20 bearing member 21 bearing recess 22 contact protrusion 23 stopper 26 Hairspring fixing part 27 Slit 28 Beard holding part 29 Outer cover 30 Bearing part

Claims (1)

[Claims] 1. A cross coil is formed by winding two coils around a coil bobbin in directions orthogonal to each other.
A magnet rotor is rotatably arranged around the rotor shaft inside the cross coil, and a drive gear that meshes with an output gear provided on the rotor shaft is provided in the vicinity of the rotor shaft. The attached drive shaft is rotatably arranged, and a balance spring for urging the pointer in the zero position direction is attached to the drive shaft, and according to the combined magnetic field of the magnetic fields generated by the coils when the coils are energized. A cross-coil type indicator instrument that drives the magnet rotor to rotate by a predetermined angle and returns the pointer to the zero position by the balance spring when the coils are not energized. A cross-coil type indicator instrument characterized in that a hairspring main body fixing part to which one end is fixed is integrally formed.