JPH0557671U - Crossed coil instrument - Google Patents

Abstract

(57) [Summary] [Structure] X coil 4 on bobbin 1 containing movable magnet 6
And the Y coil 5 are wound orthogonally. A drive shaft 7 having a rotary gear 8 fixed to the movable magnet 6 is provided. A pointer 13 and a pointer shaft 12 are fixed to a transmission gear 9 that meshes with the rotary gear 8. The pointer shaft 12 is provided in the support hole 11 of the holding portion 10 located on the extension line of the magnetic field generated by the X coil 4 so as to be capable of instructing rotation. [Effect] By only adjusting the number of winding turns of the X coil 4, the magnetism of the pointer shaft 12, which causes the error in the finger characteristic, is canceled and the error in the finger characteristic can be easily corrected.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a cross-coil type instrument used as an auxiliary instrument such as an automobile speedometer, a tachometer, a thermometer, and a fuel gauge.

[0002]

[Prior Art]

 This type of cross-coil type instrument is disclosed, for example, in Japanese Utility Model Laid-Open No. 2-67268 and Japanese Utility Model Laid-Open No. 2-67269. The structures disclosed in these publications will be described. A movable magnet is housed in a bobbin with a projecting terminal mounting part, and a coil is crossed and wound around the outer peripheral surface of the bobbin to form a cross coil. A drive shaft fixed to the movable magnet is provided so that it can be driven by a synthetic magnetic field generated by energizing cross coils corresponding to the amount. In addition, a gear is fixed to the tip of the drive shaft, and a pointer shaft is fixed to another gear that meshes with this gear, and one end of this pointer shaft is formed on the bobbin. While bearing the bearing so that rotation can be instructed at the mounting part, insert the other end of the pointer shaft, that is, the tip end from the gear and attach the pointer to this inserted part, or the tip end part of this pointer shaft. A pointer is attached to the gear portion located coaxially with the gear.The drive mechanism drive mechanism transmits the drive shaft drive to the pointer shaft, enabling the pointer to perform the indicated movement on the scale of the display plate. There is.

With such a configuration, the pointing angle range of the pointer can be expanded via the transmission mechanism by the gear, and different types of cross-coil type instruments such as a fuel gauge and a thermometer are arranged close to each other. It has the advantage of being able to effectively utilize the limited space.

By the way, this type of cross-coil type instrument combines the magnetic fields generated in the respective coils according to the amount of current flowing in each of the two coils orthogonal to each other based on the signal output according to the measured amount of the object to be measured. That is, since the movable magnet is rotated by a synthetic magnetic field and the instrument is precise and difficult to adjust, when setting the pointer shaft within the range of magnetic action for driving the instrument, The shaft is preferably made of non-magnetic material.

[0005]

[Problems to be solved by the device]

 However, if the pointer shaft is made of a non-magnetic material such as stainless steel, there is a problem in that it is difficult to maintain the hardness or strength of the pointer shaft while increasing the cost of the material itself. The material used was a magnetic material such as carbon tool steel. As a result, the pole of the movable magnet is attracted to the magnetism of the pointer shaft, which adversely affects the preset desired finger characteristic by adjusting the number of windings of the coil.

Therefore, in consideration of this point, as described in, for example, Japanese Utility Model Laid-Open No. 1-146165, an end of the pointer shaft opposite to the end of the pointer shaft on which the pointer is mounted affects the movable magnet. A structure that does not extend deeply to the bobbin position may be considered, but if the wall thickness of the height mounting portion of the bobbin for the pointer shaft is relatively thin, consider the lower bearing of the pointer shaft and use the bobbin for holding the bearing. Since the wall thickness is required, it is difficult to adopt the structure described in the above publication.

The present invention has been made in view of the above problems, and even if a pointer shaft having magnetism is used, it is possible to easily correct the error in the finger characteristic due to the magnetism of the pointer shaft. It seeks to provide a possible alternating coil instrument.

[0008]

[Means for Solving the Problems]

 According to the present invention, two coils are wound around a bobbin so as to be orthogonal to each other, and an alternating coil is provided inside the intersecting coil, which is rotated according to a combined magnetic field generated by energizing each coil. A movable magnet movably provided in the bobbin in a housed state, a drive shaft fixed to the movable magnet, a rotary gear attached to the tip of the drive shaft, and a transmission meshing with the rotary gear. The gear is fixed, the pointer is provided, and the pointer shaft is rotatably arranged on an extension line of the one side coil of the cross coil in the magnetic field direction.

[0009]

【Example】

 The drawings show an embodiment of the present invention. First, the structure of the present embodiment will be described with reference to FIGS. In the figure, reference numeral 1 denotes a bobbin which is divided into upper and lower halves, and a leg portion 2 and a cylindrical portion 3 are formed on the outer peripheral surface of the bobbin 1 so as to project, and a Y coil 4 and an X coil 5 intersect each other. The coils 4 and 5 intersecting each other, that is, the intersecting coils are formed. Reference numeral 6 denotes a movable magnet housed in the bobbin 1 so as to be pivotally movable. A drive shaft 7 is fixedly inserted through the movable magnet 6, and one end of the drive shaft 7 is at the bottom of the bobbin 1. The bearing is supported by the bearing, and the other end is provided by being inserted from the cylindrical portion 3. Reference numeral 8 is a rotary gear press-fitted and fixed to the tip of the drive shaft 7, 9 is a transmission gear meshing with the rotary gear 8, and this transmission gear 9 has a support hole 11 for a flange-shaped holding portion 10 formed on the bobbin 1. A pointer shaft 12 provided so as to be capable of instructing rotation is fixed by press fitting. Further, in the case of the present embodiment, the pointer shaft 12 is provided on the extension line of the X coil 5 in the magnetic field direction. Reference numeral 13 is a pointer, and the pointer 13 is provided by means such as press fitting or adhesion to a protrusion 14 for mounting the pointer 13 formed on the transmission gear 9 portion coaxially with the pointer shaft 12. To install the pointer 13, the transmission gear 9 may be provided through the pointer shaft 12, the tip of the pointer shaft 12 may be inserted into the transmission gear 9 by a predetermined dimension, and the pointer 13 may be attached directly to the tip. .

As a result, the movable magnet 6 is caused to rotate in response to the composite magnetic field generated by the energization of the intersecting coils 4 and 5, and the drive of the drive shaft 7 side due to the rotation of the movable magnet 6 is performed by the rotary gear 8. And, it is transmitted to the pointer shaft 12 side via the transmission gear 9 and the pointer 13 is provided so as to be capable of angular movement.

Numeral 15 is a shield case for cutting off disturbance factors such as geomagnetism, and numeral 16 is for electrically connecting the coils 4, 5 to each other, so that each coil 4, 5 and an external electric component such as a print substrate (not shown) are electrically connected. This is a relay terminal to be connected to the terminal 16. The ends of the coils 4 and 5 are soldered to the terminal 16, and the terminal 15 is a terminal mounting unit formed integrally with the leg 2 of the bobbin 1. It is press-fitted and fixed to the portion 17.

Next, the operation of the present invention will be described with reference to FIGS. First, FIGS. 3 to 7 show the positional relationship between the rotation of the magnetic pole of the movable magnet 6 and the pointer shaft 12 having magnetism, in which N and S are magnetic poles and the arrow A is the direction of the magnetic field. The arrow F indicates the error (size and rotation direction) that the pointer shaft 12 exerts on the rotation direction of the magnetic pole of the movable magnet 6.

In FIG. 3, the magnetic pole of the movable magnet 6, in this case the N pole, is opposed to the pointer shaft 12 and is at a position of 0 ° from the position of the needle shaft 12, that is, it is the closest to the pointer shaft 12 in terms of distance. Since the N pole of the movable magnet 6 is in the position, the N pole of the movable magnet 6 is most strongly attracted to the pointer shaft 12, so that the error exerted on the rotating direction of the movable magnet 6 is zero.

In FIG. 4, the N pole of the movable magnet 6 is located at a position rotated by 45 ° from the position of the pointer shaft 12, that is, the magnetic poles of the pointer shaft 12 and the movable magnet 6 are such that the N pole is farther than the S pole. Therefore, the north pole is attracted to the magnetism of the pointer shaft 12 to cause an error of arrow F in the rotating direction of the movable magnet 6.

In FIG. 5, the N pole of the movable magnet 6 is at a position rotated by 90 ° from the position of the pointer shaft 12, that is, the magnetic poles of the pointer shaft 12 and the movable magnet 6 are equal in distance between the N pole and the S pole. Therefore, the forces attracted to the pointer shaft 12 are balanced and the error exerted on the rotating direction of the movable magnet 6 becomes zero.

In FIG. 6, the N pole of the movable magnet 6 is at a position rotated by 135 ° from the position of the pointer shaft 12, that is, the magnetic poles of the pointer shaft 12 and the movable magnet 6 are S poles rather than N poles. Since they are close in distance, the S pole is attracted to the magnetism of the pointer shaft 12 and causes an error of arrow F 1 in the rotating direction of the movable magnet 6. Then, as shown in FIG. 7, when the N pole of the movable magnet 6 is rotated by 180 ° from the position of the pointer shaft 12, as in the case of FIG. The error in the direction of rotation of the magnet 6 is zero.

The figure shows the error that affects the rotating direction of the movable magnet 6 due to the magnetic action based on the positional relationship between the pointer shaft 12 and the magnetic pole of the movable magnet 6 due to the rotation of the movable magnet 6. 8, the vertical axis indicates an error associated with the rotation of the movable magnet 6, and the horizontal axis indicates the rotation angle of the movable magnet 6 with the N pole as a reference.

In this embodiment, when the pointer shaft 12 is positioned on the extension line of the X coil 5 in the magnetic field direction as shown in FIG. In order to cancel the force exerted by the pointer shaft 12 on the movable magnet 6 with respect to the dynamic angle, a coil X'which generates a waveform as shown in FIG. 9 is added to the X coil. This shows the difference in the strength of the combined magnetic field of X and Y, X + X 'and Y shown in FIG. 10 as an error. That is, FIG. 11 is a diagram in which the errors shown in FIG. 8 and the errors shown in FIG. 9 are associated and superposed, and thus, in either one of the coils 4 and 5, in this case, the X coil 5 is By creating a new error, it is possible to easily cancel each other out of error.

In this embodiment, since a new generated magnetic field is added to the X coil 5 in order to cancel the force direction of the error of the finger characteristic due to the magnetism of the pointer shaft 12, the number of winding turns of the X coil 5 is changed. Although it is set to increase, the resistance of the X coil 5 increases due to the increase in the number of winding turns, and the amount of current flowing through the X coil 5 decreases, and along with this, a new coil is added. The generated magnetic field may become weak, and in this case, the number of winding turns may be reduced and a new generated magnetic field may be added, which can be set according to various conditions.

Further, although the present embodiment shows the setting in the case where the pointer shaft 12 is provided on the extension line of the magnetic field generated by the X coil 5, the position where the pointer shaft 12 is provided is on the extension line of the magnetic field generated by the Y coil 4. In this case, the number of winding turns of the Y coil 4 may be adjusted and a new magnetic field may be added.

[0021]

[Effect of the device]

 The present invention provides a cross coil that is formed by winding coils around a bobbin so as to be orthogonal to each other, and is capable of pivoting movement according to the combined magnetic field of each coil that is generated by energization of each coil inside the cross coil. The movable magnet installed inside the bobbin, the drive shaft fixed to the movable magnet, the rotating gear mounted on the tip of the drive shaft, and the transmission gear meshing with the rotary gear are fixed. And a pointer shaft arranged so as to be capable of instructing rotation on an extension line of the coil on one side of the cross coil in the magnetic field direction. An alternating-coil instrument that can easily correct the error in the finger characteristic due to the magnetism of the pointer shaft by simply adjusting this coil so that a new magnetic field is applied to either coil. It is possible to provide.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a diagram illustrating a rotating position of a movable magnet.

FIG. 4 is a diagram illustrating a rotating position of a movable magnet.

FIG. 5 is a diagram illustrating a turning position of a movable magnet.

FIG. 6 is a diagram illustrating a rotating position of a movable magnet.

FIG. 7 is a diagram illustrating a rotating position of a movable magnet.

FIG. 8 is a diagram illustrating an error when a pointer shaft having magnetism is used.

FIG. 9 is a diagram illustrating an error when a new generated magnetic field is added to the X coil.

FIG. 10 is a diagram showing respective synthetic magnetic fields of X and Y and X + X ′ and Y.

11 is a diagram in which FIG. 8 and FIG. 9 are combined.

[Explanation of symbols]

 1 bobbin 4 Y coil 5 X coil 6 movable magnet 7 drive shaft 8 rotary gear 9 transmission gear 10 holding part 11 support hole 12 pointer shaft 13 pointer 15 shield case 16 terminal A magnetic field direction F error

Claims (1)

[Scope of utility model registration request] 1. A cross coil provided by winding coils on a bobbin so as to be orthogonal to each other, and a rotary motion according to a combined magnetic field of each coil generated by energization of each coil provided inside the cross coil. A movable magnet that is installed in the bobbin so that it can be accommodated, a drive shaft that is fixed to the movable magnet, a rotary gear that is attached to the tip of the drive shaft, and a transmission gear that meshes with the rotary gear. A cross-coil type instrument which is fixed and has a pointer, and further includes a pointer shaft arranged so as to be capable of instructing rotation on an extension line of the one side coil of the cross coil in the magnetic field direction.