WO1999006846A1

WO1999006846A1 - Electric measuring instrument

Info

Publication number: WO1999006846A1
Application number: PCT/JP1998/003369
Authority: WO
Inventors: Shuichi Nomizu; Kouichi Satoh
Original assignee: Nippon Seiki Co., Ltd.
Priority date: 1997-07-31
Filing date: 1998-07-27
Publication date: 1999-02-11
Also published as: JPH1151973A

Abstract

An electric measuring instrument provided with an instrument body (1) incorporating a bobbin (3) constituted by fixing a moving magnet (6) to a pointer shaft (5) fitted with a pointer (4) and winding a coil (2) around the magnet (6) and a printed board (15) mounted with electric parts, etc., for impressing signals on the body (1). The main body (1) is provided with terminals (14) electrically connected to the end portion of the coil (2) and also with coupling means (16) electrically connected to the terminals (14) and electrically and mechanically connected to the printed board (15) by rotating the body (1) around the axial center of the pointer shaft (5). As a result, the instrument can dispense with the soldering step due to its simple constitution and the instrument body (1) can be electrically connected to the printed board (15) through single action with high workability.

Description

Details

Technical field

According to the present invention, a movable magnet is fixed to a pointer shaft having a pointer attached thereto, and a coil is wound around the movable magnet. The present invention relates to an electric instrument electrically connected. Background art

In general, a movable magnet type instrument as an electric instrument of this type includes a synthetic magnet incorporating a movable magnet as disclosed in, for example, Japanese Utility Model Publication No. 3-28862 published by the Japan Patent Office. A coil is wound around a resin pobin, and the upper end of a pointer shaft provided on the movable magnet is protruded from the pobin, and a pointer is attached to the tip.

This conventional electric meter has a structure in which an electric wire is connected to the outside of the bobbin, which is the main body of the meter, on the surface opposite to the surface on which the hands are attached, as an electric wiring structure with the outside. Alternatively, a structure is adopted in which a terminal connected to an end of the coil provided at an appropriate position of the bobbin is connected by being tightened and fixed with a screw, a nut, or the like from the outside of the case for housing the instrument body.

Further, as another electrical connection means, as disclosed in Japanese Patent Application Laid-Open No. Hei 7-13971 issued by the Japan Patent Office and Japanese Patent Application Laid-Open No. 8-56667, In some cases, electrical connection can be made with a single touch by inserting and fitting each other between female and printed circuit boards using female and male connector members.

Another example of a stepping motor type instrument as an electric instrument is a conventional stepping motor, such as that disclosed in Japanese Patent Application Laid-Open No. 9-149619 issued by the Japan Patent Office. The movable magnet fixed to the pointer shaft, which extends along the axis of the pobin and has the pointer fixed at the top, is provided in the hollow portion of the pobin. It is arranged rotatably and gives the magnetic field of the coil to the movable magnet. For this purpose, a metallic comb-shaped yoke formed over the bobbin is provided for each of the upper and lower pobins, and the metal upper and lower plates that are stacked on the yokes and accommodate the movable magnets are provided. It is constituted by providing.

A terminal is provided on the flange of the bobbin. The terminal of the coil of the bobbin is wound around one end of the terminal and soldered, and the other end of the terminal is formed downward toward the printed circuit board. The terminals are soldered directly to the printed circuit board to supply current to the pobin from the printed circuit board.

As described above, in the conventional movable magnet type meter, since the number of screws and nuts corresponding to the number of coils pulled out from the bobbin are configured to be electrically and mechanically connected, the drawn-out length is obtained. The work required to tighten screws and nuts equivalent to the number of coils was required, and workability was poor.

In addition, when the electrical connection means consisting of female and female connectors is adopted, the workability is somewhat improved, but electrical connection parts such as female terminals or female terminals are provided on both the instrument body and the printed circuit board. It was necessary to provide it, and it was easy to become structurally complicated. Also, in the stepping mode, it is common to solder a terminal that is hung downward from the bobbin flange through a hole in a land formed on the printed circuit board. There was also a request to omit.

Therefore, an object of the present invention is to provide an electric instrument that can eliminate the soldering process with a simple configuration and can electrically connect the instrument body to a printed circuit board with one touch with good workability. . Disclosure of the invention

The present invention will be described by taking, as an example, an instrument body composed of a stepping motor. This stepping motor is provided with a resin bobbin on which a coil is wound on the upper and lower stages coaxially and along the axis of the pobin. A movable magnet fixed to the pointer shaft, which is extended and has a pointer fixed at the top, is rotatably arranged in the hollow part of the pobin, and a metallic metal formed over the pobin to apply the magnetic field of the coil to the movable magnet. A comb-shaped yoke is provided for each of the upper and lower bobbins, and an upper plate made of synthetic resin and a lower plate made of metal are stacked on the yokes to house the movable magnets. Instrument body is provided.

A terminal is provided on the flange of the pobin, and the terminal of the coil of the pobin is wound around one end of the terminal and soldered, and the other end of the terminal rises vertically toward the top plate. are doing. The upper plate is provided with joining means for electrically and mechanically connecting to the printed circuit board. This joining means includes terminals formed downward from the flange of the bobbin toward the upper plate, in addition to terminals. An electric relay portion, which is soldered and connected through the end portion, and an upper holding piece and a lower holding piece for holding and fixing the printed circuit board are provided above the electric relay portion, and the upper and lower pobins of the stepping motor are provided. The number of coupling means corresponding to the number of coils pulled out from the plate is insert-molded on the upper plate.

The printed circuit board is provided with an insertion hole at a position corresponding to the coupling means.Around the insertion hole, a land portion connected to a predetermined electric component or a circuit of the printed circuit board is provided. The upper holding piece, which is a connecting means, is inserted into the insertion hole, and then the stepping motor, which is the main body of the instrument, is rotated by a predetermined angle about the axis of the pointer shaft. by the upper clipping piece in contact with the land portion with a Chakuhen held by sandwiching the printed circuit board, the instrument body and pre - substrate and is _a _ drawings to which electrical power one mechanically connected easy explanation

FIG. 1 is an exploded perspective view of an instrument main body used in a first embodiment of the present invention, FIG. 2 is a sectional view showing the first embodiment of the present invention before assembling, and FIG. FIG. 4 is a perspective view showing a first embodiment of the present invention, FIG. 4 is a cross-sectional view after assembling showing a first embodiment of the present invention, and FIG. 5 is a main part of the first embodiment of the present invention. FIG. 6 is a perspective view showing a second embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION ''

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIGS. 1 to 5 illustrate the first embodiment of the present invention, taking an electric instrument main body 1 composed of, for example, a stepping motor. The instrument body 1 consisting of this stepping motor is a coil A movable magnet 6 fixed to a pointer shaft 5, which is provided with a resin-made pobin 3 wound around 2 at the upper and lower stages coaxially and extends along the axis of the pobin 3 and has a pointer 4 fixed on the upper portion. Are rotatably arranged in the hollow portion 7 of the bobbin 3, and the metallic comb-shaped yokes 8 formed over the pobin 3 to apply the magnetic field of the coil 2 to the movable magnet 6 are provided on the upper and lower bobbins. 3 and a top plate 9 made of synthetic resin and a bottom plate 10 made of metal, which are stacked on the yoke 8 and house the movable magnets 6, are provided on the top plate 9 and the bottom plate 10 The pointer shaft 5 is supported by the bearings 11 and 12 provided.

Also, four L-shaped terminals 14 are provided on the flange portion 13 of the upper bobbin 3 by insert molding corresponding to the coils 2 of the upper and lower pobins 3, and one of these terminals is provided on one side. The terminal 14a of the terminal 14a corresponds to the upper pobin 3 and the terminal 14 of the other side corresponds to the lower bobbin 3.One end of these terminals 14a and 1.4b is provided. The ends of the coil 2 of the pobin 3 are wound around and soldered, and the other ends of the terminals 14 a and 14 b are formed so as to rise vertically toward the upper surface plate 9. The upper surface plate 9 is provided with joining means 16 for electrically and mechanically connecting to the printed circuit board 15, and the joining means 16 is, as shown in FIG. Standing up from the flange 13 to the upper surface plate 9: The other ends of the terminals 14 a and 14 b to be formed are inserted into the hole 17 and the electric relay 18 connected by soldering. Above it, an upper holding piece 19 and a lower holding piece 20 for holding and fixing the printed circuit board 15 are integrally press-formed by a conductive member. A number of coupling means 16 corresponding to the number of ends of the coil 2 drawn out from the upper and lower bobbins 3 are concentrically arranged on the upper surface plate 9 with the pointer shaft 5 as a base point, and are insert-molded. The upper sandwiching piece 1 '9 and the lower sandwiching piece 20 are each provided with a bent portion 21 that is convex toward the printed circuit board 15 side so as to increase the contact force with the printed circuit board 15. It is formed into a rigid shape.

The printed circuit board 15 is made of a hard wiring board having electric parts and circuit patterns (not shown) for applying signals to the instrument body 1. The printed circuit board 15 has a pointer at a position corresponding to the coupling means 16. A generally arcuate insertion hole 22 centered on the shaft 5 is provided, and the through hole 22 is formed by an inlet portion 2 2a into which the upper sandwiching piece 19 is inserted and the inlet hole 2 2a. A fixed portion 2 2 b narrower than the portion 22 a is formed. Around the through hole 22, a land portion 2 connected to a predetermined electric component or circuit (not shown) of the printed board 15 is provided. 3 is provided on the upper surface side, and the upper clamping piece 19, which is the coupling means 16, is inserted into the inlet part 2 2a of the insertion hole 22.Then, the instrument body 1 is moved with the axis of the pointer shaft 5 as the base point. By rotating by a predetermined angle, the upper holding piece 19 and the lower holding piece 20 hold and hold the fixed portion 2 2 b of the printed circuit board 15, the land portion 23 on the peripheral edge of the printed circuit board 15, and hold the upper holding piece. The instrument body 1 and the printed circuit board 15 are electrically and mechanically connected by the contact of the piece 19 with the land portion 23.

With the above configuration, the meter main body 1 having the coupling means 16 is simply inserted into the printed circuit board 15 in such a manner as to match with the through hole 22 of the printed circuit board 15, and the meter main body 1 is rotated by a predetermined angle to print the meter main body 1. Mechanical fixation and electrical connection to the substrate 15 can be achieved, and one-touch assembly work can be performed with a relatively simple structure without soldering.

Further, since the coupling means 16 is provided with the upper sandwiching piece 19 and the lower sandwiching piece 20, the land portion 23 is on the upper surface side of the printed board 15 as in the first embodiment described above. Not only in this case, but not shown, electrical connection is possible even when the land portion is only on the lower surface side of the printed circuit board 15. In this case, the lower holding piece 20 is connected to the lower surface of the printed circuit board 15. The electrical connection is made by contacting the land portion on the side. Thus, the joining means 16 of the instrument main body 1 can make electrical connection even when the land portion 23 is only on the upper surface side of the printed circuit board 15 or when it is only on the lower surface side. And improved versatility.

In addition, in particular, regarding the stepping motor, according to the conventional stepping motor structure, since the electric connection is carried to the solder tank together with the printed circuit board and soldered, it receives heat during the soldering process. As a result, the movable magnet housed inside the instrument body also receives heat, and this heat may reduce the magnetic force and reduce the rotational torque. However, according to the present invention, the soldering process is performed. Since the main body of the instrument can be assembled as soon as possible, mounting the specified electric parts on the printed circuit board and assembling the main body after soldering can also prevent a decrease in rotational torque due to heat during soldering as in the past. it can.

FIG. 6 shows a second embodiment of the present invention. Instrument body 1 and printed circuit board 1 Positioning means 24 that engages at a predetermined rotation position of the instrument main body 1 is provided at a portion facing the instrument 5 .Specifically, a convex portion 25 is provided at a predetermined position of the upper surface plate 9, At the time of assembling the main body 1 to the printed circuit board 15, the instrument main body 1 is turned by a predetermined angle, and the upper holding piece 19 turns the instrument main body 1 corresponding to the land 23 of the printed circuit board 15. The holes 26 are formed in the printed circuit board 15 at the corresponding positions with the projections 25 so as to correspond to the positions.

In this way, when the meter main body 1 is rotated by a predetermined angle when the instrument main body 1 is mounted on the printed circuit board 15, the convex portion 25 of the upper surface plate 9 engages with the hole 26 of the printed circuit board 15. The operator can recognize that the instrument body 1 has been rotated to the predetermined rotation position, and the upper holding piece 19 of the engagement means 16 is in the appropriate position corresponding to the land portion 23. Is set.

In addition, since the positioning means 24 can prevent the instrument main body 1 from being attached to the printed circuit board 15 in the assembled state, for example, the instrument main body 1 can be rotated with respect to the printed circuit board 15 by the vibration of the vehicle. It is also possible to prevent a situation in which the upper holding piece 19 is shifted from the land portion 23 of the printed circuit board 15 to cause a contact failure.

Further, in the second embodiment and the example, an annular boss portion 27 centering on the pointer shaft 5 is provided around the pointer shaft 5 at a portion of the instrument main body 1 facing the printed circuit board 15, and printed. The board 15 is provided with a guide portion 28 through which the boss 27 can be inserted.The guide portion 28 of the print board 15 is formed on the upper surface plate 9 on the instrument body 1 side. By inserting the annular boss 27 and inserting the upper holding piece 19 of the coupling means 16 into the through hole 22, the instrument body 1 is rotated to Due to the action of the guide part 28 and the instrument body 1, the instrument body 1 can be smoothly rotated around the pointer shaft 5 without the rotational axis shifting, and the upper clamping piece 19 of the coupling means 16 can be properly adjusted. It is rotated to a predetermined position while being guided toward a land portion 23 formed on the printed board 15. The boss portion 27 and the guide portion 28 make it possible to relatively easily insert the upper holding piece 19 of the joining means 16 into the through hole 22 of the printed circuit board 1. Become.

In each embodiment, the connecting means 16 having the structure shown in FIG. Although a plurality of bosses are provided on a circle, in the structure in which the boss portion 27 is provided as in the second embodiment, the joining means 16 is provided on the outer periphery of the boss portion 27, and the printed circuit board 15 is provided. The land portion 23 may be formed on the periphery of the guide portion 28 so as to be connected. The structure and the position of the connecting means 16 can be freely set.

Further, in the above-described embodiment, only the example in which the instrument main body 1 is provided on the lower surface of the printed circuit board 15 is shown, but the instrument body 1 may be provided on the upper surface of the printed circuit board 15, and in this case, The connecting means 16 may be provided at the bottom of the instrument body 1.

The printed circuit board 15 is not limited to a rigid printed circuit board. A printed circuit board made of a flexible FPC is provided alongside a case (not shown), and a through hole is formed in this case and the FPC to form the instrument body. The instrument body may be mechanically and electrically connected to the land portion provided on the FPC by inserting the connecting means and rotating the meter body with respect to the case.

Further, the positioning means 24 is provided between the instrument body 1 and the printed circuit board 15, that is, the upper surface plate 9 and the printed circuit board 15 which are components of the stepping motor in the above-described embodiment. However, the positioning means 2 may be provided between the joining means 16 and the printed circuit board 15, or the positioning means 2 may be provided by engaging the convex part 25 with the hole 26. The value is not limited to -4, and may be obtained by other means. As described above, according to the present invention, it is possible to provide an electric instrument that can eliminate the soldering process with a simple configuration and can electrically connect the instrument body to a printed circuit board with good workability. . Industrial applicability

In the above-described embodiment, the stepping motor has been described as an example of the meter main body 1. However, the present invention is also applicable to an electric meter using another meter main body, such as a cross-coil movable magnet type meter. It is.

Claims

Range of request

1. A movable magnet is fixed to the pointer shaft on which the pointer is mounted, an instrument body with a pobin formed by winding a coil around the movable magnet, and electric components for applying signals to the instrument body are assembled. A printed circuit board, wherein the instrument main body is provided with a terminal electrically connected to a coil end of the instrument main body, and electrically connected to the terminal, and the instrument is provided with the axis of the pointer shaft as a base point. An electric instrument, comprising: coupling means for making an electrical and mechanical connection with the print substrate by rotating a main body.

2. The positioning device according to claim 1, wherein positioning means for engaging at a predetermined rotation position of the meter main body is provided at a facing portion between the meter main body and the printed circuit board.

3. The coupling means has an upper holding piece and a lower holding piece, and the printed circuit board is held between the upper holding piece and the lower holding piece. 2. The electric meter according to claim 1, wherein ―

4. An annular or column-shaped boss centered on the needle axis is provided around the pointer shaft of the instrument body facing the printed board, and the boss is inserted through the printed board. Claim 1 characterized by providing a possible guide portion