JPH05215779A - Cross coil type gauge - Google Patents

Abstract

PURPOSE:To obtain a cross coil type gauge which enables accurate display adjustment of a pointer with easier correction of direction of combined vectors of a magnetic force. CONSTITUTION:A bobbin 10 containing a mobile magnet is wound with a coil 12 and a rotating shaft 13 of the mobile magnet is provided with a pointer. The bobbin 10 is housed in a case 15 for shielding and an external magnet 21 for reset to zero is arranged between the bobbin 10 and the case 15. In a cross coil type gauge of such a type, an adjusting metal piece 3 for display adjustment of the pointer 14 is disposed near the external magnet 21. The adjusting metal piece 3 is made to approach the external magnet 21, for example, by bending it. Thus, the display adjustment of the pointer is accomplished by adjusting a flux density of the external magnet 21.

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 instrument, and more particularly to a structure capable of easily and reliably adjusting the display of its pointer.

[0002]

2. Description of the Prior Art As shown in FIG.
And a pointer 14 is provided on the rotary shaft 13 of the movable magnet, and the bobbin 10 has a case 15 for magnetic shielding.
It is stored in. An external magnet 21 for driving and zeroing is arranged in the case 15 so as to face the bobbin 10. When this cross-coil type meter 1 is used as a voltmeter, as shown in FIG. 11, the display angle of the pointer is changed according to the measured voltage.

That is, as shown in FIG.
The coil 12 wound around generates a coil magnetic field vector C having a magnitude proportional to the input voltage. On the other hand, there is an external magnet vector M of a certain size according to the magnetic force of the external magnet. Therefore, the combined vector direction V of both
When the rotary shaft 13 provided on the movable magnet 101 rotates in response to 1 or V2, the pointer indicates a predetermined voltage display position. It should be noted that the figure shows vector changes in the combined vector direction V1 when the input voltage is small (DN) and in the combined vector direction V2 when the input voltage is large (DM).

[0004]

[Problems to be Solved] However, the conventional cross-coil type instrument does not have a display adjustment function. In addition, the cross-coil type instrument has a composite vector direction for each product due to variations in the coil resistance value of the coil 12 wound around the bobbin 10, variations in the material of the external magnet, and variations in the size of the external magnet. May not be constant. Therefore, there is a problem that the display angle of the pointer varies.

That is, this will be described with reference to FIGS. First, FIG. 12 shows a case where the coil resistance values vary. In this case, the coil magnetic field vector is increased by C1 when the coil resistance value is the minimum when the coil resistance value is the minimum. Assuming that the external magnet vector M is constant, the combined vector direction has a difference between the directions of V3 and V4 when the coil resistance value is maximum and when the coil resistance value is minimum.

Further, FIG. 13 shows a case where the magnetic force of the external magnet is varied. In this case, when the magnetic force is maximum, the external magnet vector is larger by M1 than when the magnetic force is minimum. Assuming that the coil magnetic field vector C is constant, a difference between the directions of V5 and V6 occurs in the combined vector direction when the magnetic force of the external magnet is minimum and maximum.

Therefore, even if the input voltage is the same, the display position of the pointer will be different for each product of the cross coil type instrument due to the variation of the coil and the external magnet. In view of the above conventional problems, the present invention intends to provide a cross-coil type instrument that can easily correct the above-mentioned combined vector direction and can perform accurate display adjustment of the pointer.

[0008]

According to the present invention, a coil is wound around a bobbin containing a movable magnet and a pointer is provided on the rotating shaft of the movable magnet, and the bobbin is housed in a case for magnetic shielding, and the bobbin is further contained. In a cross-coil type instrument in which an external magnet that mutually exerts a magnetic action on the movable magnet is disposed between the case and the case, in the vicinity of the external magnet, an indicator for adjusting the display of the pointer is provided. An intersecting coil type instrument is characterized in that an adjusting metal piece is provided, and the display position of the pointer is adjusted by adjusting the relative position between the external magnet and the adjusting metal piece. What is most noticeable in the present invention is that the magnetic flux density of the external magnet is adjusted by disposing the adjusting metal piece near the external magnet and adjusting the relative position between the adjusting metal piece and the external magnet. It is configured to change the direction of the composite vector, that is, to adjust the display of the pointer.

The adjusting metal piece is a metal body for adjusting the magnetic flux density by moving the adjusting metal piece close to or away from the external magnet to correct the combined vector direction. A magnetic metal material such as a silicon steel plate or permalloy is used as the adjusting metal piece. The adjusting metal piece is arranged near the external magnet. As the arrangement method,
Use a part of the magnetic shield case near the external magnet as a projecting piece (Figs. 1 to 3), arrange it between the external magnet and its fixing plate (Figs. 8 and 9), or There is a method of holding a clip-shaped adjusting metal piece between the attached magnet and the case (FIG. 10).

As a method of changing the magnetic flux density between the adjusting metal piece and the external magnet, there is a method of adjusting the angle at which the adjusting metal piece is bent in the direction of the external magnet, and a method of adjusting the angle between the adjusting metal piece and the external magnet. To adjust the facing area of
There is a method of adjusting the distance between the adjusting metal piece and the external magnet.

[0011]

In the cross coil type instrument of the present invention, the adjusting metal piece is arranged in the vicinity of the external magnet. When adjusting the display of the pointer, the magnetic flux density of the external magnet is adjusted by moving the adjusting metal piece closer to or further from the external magnet, for example. As a result, the combined vector direction formed by the external magnet vector and the coil magnetic field vector is adjusted to the normal direction. Therefore, the display position of the pointer rotated by the combined vector direction becomes an accurate position, and the display adjustment of the pointer can be easily and accurately performed. Therefore, according to the present invention, it is possible to provide a cross-coil type instrument that can easily correct the combined vector direction and can perform accurate display adjustment of the pointer.

[0012]

【Example】

Example 1 FIG. 1 shows a cross coil type instrument according to an example of the present invention.
~ It demonstrates using FIG. Crossed coil type instrument 1 of this example
As shown in FIG. 1, a coil 12 is wound around a bobbin 10 containing a movable magnet (not shown), and a pointer 14 is provided on a rotary shaft 13 of the movable magnet. The bobbin 10 serves as a magnetic shield. It is stored in the case 15. Further, an external magnet 21 for driving and zeroing is disposed in the surplus space between the bobbin 10 and the case 15 so as to have a mutual magnetic action with the movable magnet.

In the vicinity of the external magnet 21, an adjusting metal piece 3 for adjusting the display of the pointer is extended with a part of the upper end of the case 15 protruding. As shown in FIGS. 1 to 3, the external magnet 21 has a fixing plate 22.
It is fixed to the inner wall of the case 15 in a state of being adhered to. The case 15 and the adjustment metal piece 3 are made of a metal material such as permalloy. Further, FIG. 4 shows an overall perspective view of the cross coil type instrument in which the display panel 141 is fixed on the case 15. Reference numeral 142 is a display mark.

Next, the function and effect of this example will be described. First, when adjusting the display of the pointer, as shown in FIG. 2, the tip 31 of the adjusting metal piece 3 is bent above the external magnet 21. As a result, the magnetic flux density of the external magnet 21 changes. The magnetic flux density of the external magnet 21 can be adjusted by changing the degree of bending. Therefore, as described later, the magnetic flux density between the external magnet 21 and the coil changes, the combined vector direction changes, and the pointer can be displayed and adjusted at an accurate position.

Further, the above-mentioned bending is as shown in FIG.
The adjusting metal piece 3 may be bent in a dogleg shape near the tip end portion 32 to bring the tip end portion 31 closer to the external magnet 21. These proximity means have various modes. Next, the principle of making the composite vector direction normal by bringing the adjusting metal piece 3 close to the external magnet 21 as described above will be described with reference to FIGS. First, FIG. 5 shows correction when the coil resistance value varies.

That is, in FIG. 5, it is assumed that the coil magnetic field vector C changes by C2 due to the variation in the coil resistance value. At this time, the external magnet vector is M. Therefore, the combined vector direction is V8. However, the normal composite vector direction is V7 formed by the coil magnetic field vector C and the external magnet vector M. Therefore, as described later, the above-mentioned composite vector direction V
The adjustment metal piece 3 is brought closer to the external magnet 21 so that 8 becomes the same as V7, and the magnetic flux density of the external magnet 21 is increased.

As a result, the external magnet vector is M
Increases by 2. As a result, the coil magnetic field vector C +
A combined vector direction V9 formed by C2 and the external magnet vector M + M2 is generated. The composite vector direction V9 matches the normal composite vector direction 7. Although not shown, the distance between the adjustment metal piece 3 and the external magnet 21 is also changed when the external magnet vector M is small due to variations in the external magnet 21. As a result, the magnetic flux density of the external magnet changes, the magnitude of the external magnet vector can be changed, and variations in the combined vector direction can be corrected. Therefore, the display adjustment of the pointer can be adjusted easily and accurately.

6 and 7 show the external magnet 21.
It is shown that the amount of change in the combined vector direction due to the change in the magnetic force of changes greatly depending on the magnitude of the input voltage. That is,
When the input voltage is small, as shown in FIG. 6, even if the magnetic force of the external magnet 21 changes by ΔM, the amount of change Δθ _{1 in the} combined vector direction is extremely small. On the other hand, when the input voltage is large, as shown in FIG. 7, even when the magnetic force of the external magnet changes by the same amount ΔM, the amount of change Δθ _{2 in the} combined vector direction becomes large. In the present invention, the display adjustment is possible by utilizing the difference in the variation amount in the combined vector direction.

To explain this point in more detail,
Comparing the pointing accuracy of the pointer at the pointer press-fitting point, that is, the pointer position when the pointer 14 is press-fitted to the rotary shaft 13 and the other points, the pointing accuracy is determined only at the pointer press-fitting point by the press-fitting accuracy. On the other hand, in other points, the pointing accuracy is determined by the sum of the variations in the press-fitting accuracy and the deflection angle of the pointer. for that reason,
It can be seen that the pointing accuracy is highest at the pointer press-fitting point. As described above, the display adjustment is performed by the following method in consideration of the difference in the degree of influence on the direction of the composite vector.

That is, first, the pointer 14 is pressed into the rotary shaft 13 at the minimum input voltage point. Then, the input voltage is increased, and the adjusting metal piece 3 is deformed in the direction of the external magnet 21 so that the pointer 14 shows an accurate target pointing angle at the input voltage. Even if the adjustment metal piece 3 is deformed as described above, the combined vector direction hardly changes at the minimum input voltage point (see the description of FIG. 6), so the precision at the pointer press-fitting point does not deteriorate.
As described above, according to the cross-coil type instrument of this example, the display adjustment can be performed easily and accurately.

Embodiment 2 In this embodiment, as shown in FIGS. 8 and 9, the external magnet 2 is used.
An adjustment metal piece 33 is vertically interposed between the fixed plate 22 and the fixed plate 22. That is, the fixed plate 22 has the locking portions 225 having the locking holes 226 at both upper ends. Also,
A protrusion 220 is provided in the center, and a recess 227 for inserting the adjustment metal piece 3 is provided on the top thereof. On the other hand, the external magnet 21 has a mounting hole 210 in the center. Then, the mounting hole 210 is press-fitted into the projecting portion 220 of the fixed plate 22, and the external magnet 21 and the fixed plate 22 are bonded with an adhesive to fix them to each other.

The external magnet section thus constructed is
As shown in the same figure, it is inserted in the surplus space 19 between the case 15 and the bobbin 10. Further, the locking hole 226 is inserted into the fixing pin 16 of the bobbin post 11 to instruct the fixing of the external magnet portion. The adjusting metal piece 33 is inserted into the recess 227 formed between the fixed plate 22 and the external magnet 21 (FIG. 9). The insertion depth is the same as in the first embodiment.
As shown in, set the display of the pointer to the correct position. That is, depending on the insertion depth of the adjustment metal piece 33, it is possible to adjust the combined vector direction. After the adjustment, the adjusting metal piece 33 is fixed to the fixing plate 22 with an adhesive.
Others are the same as in the first embodiment. Also in this example, the same effect as that of the first embodiment can be obtained.

Example 3 In this example, as shown in FIG.
It uses a clip-shaped body. The adjustment metal piece 36 is
It has a U-shape, and has bent holding portions 363 near both end portions 361 and 362 thereof. In adjusting the display of the pointer, as shown in the figure, the adjustment metal piece 36 is sandwiched between the external magnet 21 and the case 15. Then, the combined vector direction is adjusted by changing the vertical depth in the sandwiched state.
After adjustment, attach the adjustment metal piece 36 to the case 15 with an adhesive.
Stick to. Others are the same as in the first embodiment. Also in this example, the same effect as that of the first embodiment can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of a cross-coil type instrument according to a first embodiment before display adjustment.

FIG. 2 is an explanatory diagram showing a state of an adjustment metal piece after display adjustment in the first embodiment.

FIG. 3 is an explanatory view showing another state of the adjustment metal piece after display adjustment in the first embodiment.

FIG. 4 is a perspective view of a cross-coil type instrument in which a dial is attached to the main body of the cross-coil type instrument after display adjustment in the first embodiment.

FIG. 5 is an explanatory diagram of correction of a combined vector direction when a coil resistance value varies in the first embodiment.

FIG. 6 is an explanatory diagram showing a change in a combined vector direction of input voltage minimum points in the first embodiment.

FIG. 7 is an explanatory diagram showing a change in a combined vector direction at a point where the input voltage is large in the first embodiment.

FIG. 8 is an exploded perspective view of a cross coil type instrument according to the second embodiment.

FIG. 9 is an explanatory diagram of adjusting a display according to the second embodiment.

FIG. 10 is an explanatory diagram of the adjustment metal piece and display adjustment in the third embodiment.

FIG. 11 is an explanatory diagram showing a relationship between a coil magnetic field vector, an external magnet vector, and a combined vector direction in a conventional cross-coil type instrument.

FIG. 12 is an explanatory diagram of a combined vector direction in the case where a coil resistance value varies in a conventional cross coil type instrument.

FIG. 13 is an explanatory diagram of a combined vector direction in a case where a variation occurs in an external magnet vector in a conventional cross coil type instrument.

[Explanation of symbols]

 1. ． ． Crossed coil type instrument, 10. ． ． Bobbin, 12. ． ． Coil, 14. ． ． Guidelines, 15. ． ． Case, 21. ． ． External magnet, 22. ． ． Fixed plate, 3, 33, 36. ． ． Adjusting metal pieces,

Claims (1)

[Claims] 1. A coil is wound around a bobbin containing a movable magnet, and a pointer is provided on a rotating shaft of the movable magnet. The bobbin is housed in a case for magnetic shielding. In the cross-coil type instrument in which an external magnet that mutually exerts a magnetic action on the movable magnet is arranged, an adjusting metal piece for adjusting the display of the pointer is arranged near the external magnet. A cross-coil type instrument characterized in that the display is adjusted by adjusting the relative position between the external magnet and the adjustment metal piece.