JP3314725B2 - Stepping motor connection structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric connection structure between a stepping motor and a circuit board, and more particularly to a stepping motor and a circuit board suitable for using the stepping motor as a drive unit of an indicator of a moving body such as a vehicle. And the connection structure.

[0002]

2. Description of the Related Art Conventionally, an electric connection between a stepping motor and a circuit board on which a drive control circuit for driving the stepping motor is mounted has been made via an electric cable or a cable with a connector. For example, Japanese Patent Application Laid-Open No. H08-111
As shown in FIG. 6 and disclosed in Japanese Patent Application Laid-Open No. 971/97, and JP-A-5-64411, a magnet rotor 2 having a drive shaft 1 is rotatably housed and at least the output side of the drive shaft 1 projects from one side surface. The stepping motor 3 is provided with a terminal 4 extending in parallel to the axial direction of the drive shaft 1, and a circuit is provided on the back (other side) opposite to the front (one side) of the stepping motor 3 from which the output side of the drive shaft 4 projects. There has been proposed a structure in which a board 5 is arranged, and the circuit board 5 and the terminal 4 are connected by soldering or the like to directly connect the stepping motor 3 to the circuit board 5. Since the stepping motor and the circuit board can be automatically soldered on the production line, the connection work can be automated and the cost can be reduced.

In recent years, a stepping motor has been attracting attention as a driving unit (movement) of an indicating instrument of a moving body such as a vehicle. When such a stepping motor is used as a driving unit of an indicating instrument, it is shown in FIG. The hands 6 may be fixed to the tip of the drive shaft 1 of the stepping motor 3 and the instrument dial 7 may be arranged behind the hands 6. In this type of analog instrument, for example, as shown in FIG. A circuit board 5 to be soldered and connected to the terminal 4 is arranged on the front surface (one side surface) of the stepping motor 3 from which (the output side of) the drive shaft 1 projects.
(Output side) The end is made to penetrate from the circuit board 5 and the LED (light emitting diode) 8 is arranged on the circuit board 5 to illuminate the hands 6 and the instrument dial 7 through the diffusion plate 9. As a result, there are cases in which a simple structure and high-brightness illumination are aimed at, or a structure aiming at thinning the device itself is adopted.

[0004]

However, as shown in FIG. 6, when the circuit board 5 is arranged on the front surface (one side surface) of the stepping motor 3, the output side of the drive shaft 1 penetrates the circuit board 5. Automatic soldering of the terminal 4 and the circuit board 5 by the flow and reflow soldering on the production line cannot be performed, and manual soldering must be performed. Therefore, the connection workability is poor and the cost increases. In addition, since the terminal shape changes depending on the arrangement position of the circuit board 5 with respect to the stepping motor 3, the circuit board 5 is arranged on the front surface (one side surface) of the stepping motor 3 and on the rear surface (other side surface). In this case, there is a problem that the main body structure of the stepping motor changes, and a common motor main body cannot be used.

In view of these points, the present applicant has previously proposed Japanese Patent Application No. 9-45406, which is a patent application of the present applicant, which includes a stepping motor and a forward stepping motor. The circuit board to be arranged is electrically connected to the circuit board via a relay board arranged on the back surface of the stepping motor. According to such a structure, the above-described problem can be solved.

However, in Japanese Patent Application No. 9-45406, the female connection terminal on the relay board side is arranged in a cover member which is a component of the stepping motor.
The connection between the circuit board and the relay board is performed in the stepping motor by inserting and connecting the bar-shaped male connection terminal on the circuit board side to the box-shaped female connection terminal arranged in the cover member. However, the position of the male connection terminal on the circuit board side is fixed by the position of the female connection terminal arranged in the cover member, and the layout of other circuit elements conductively mounted on the circuit board is restricted. When such a circuit element includes a light emitting element for lighting such as an instrument display unit, the layout of the light emitting element is restricted, which may cause inconvenience to lighting.

SUMMARY OF THE INVENTION The present invention has been made in view of the above point, and is capable of increasing the degree of freedom in laying out circuit elements even when the stepping motor and the circuit board are electrically connected through a relay board. No connection structure is provided.

[0008]

According to the present invention, there is provided a stepping motor comprising a magnet rotor having a drive shaft rotatably accommodated therein and having at least an output side of the drive shaft protruding from one side. A stepping motor connection structure for electrically connecting a circuit board disposed so that an output side end of the drive shaft penetrates at a position facing one side surface of the stepping motor; One side is provided with a relay board electrically connected to the stepping motor on the other side opposite to the axial direction of the drive shaft, and the stepping motor and the circuit board are provided between the relay board and the circuit board. And a connecting member for electrically connecting the stepping motor and the connecting member is provided outside the stepping motor.

The present invention also provides a male type in which the connection member comprises a pair of connection terminals which are conductively mounted on each of the circuit board and the relay board, and one of the connection terminals extends in the axial direction of the drive shaft. And the other side is a female second connection terminal that can be electrically connected by inserting the first connection terminal.

Preferably, the first connection terminal is mounted on the circuit board side, and the second connection terminal is mounted on the relay board side.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A connection structure for a stepping motor according to the present invention is a magnet rotor 712 having a drive shaft.
Motor rotatably accommodated therein and having at least the output side of the drive shaft 711 protruding from one side surface.
0 and a circuit board 50 disposed so that the output side end of the drive shaft penetrates at a position facing one side of the stepping motor 70. A relay board 80 electrically connected to the stepping motor 70 is provided on the other side opposite to the first side, and the first and second relay boards 80 for electrically connecting the relay board 80 and the circuit board 50 are provided.
By arranging the second connection terminals (connection members) 52 and 81 outside the stepping motor 70, the circuit element 5
It is possible to increase the degree of freedom of the layouts 1, 53.

A connecting member for connecting the circuit board 50 and the relay board 80 is formed by a male first extending member extending in the axial direction of the drive shaft 711.
And the second connection terminal 81 of a female type that can be electrically connected by inserting the first connection terminal 52 into the first connection terminal 52 on the circuit board 50 side. The electrical connection between the stepping motor 70 and the circuit board 50 is achieved by the insertion connection with the second connection terminal 82 on the side of the stepping motor 70, and the connection workability can be improved.

Also, in particular, the first connection terminal is mounted on the circuit board side and the second connection terminal is mounted on the relay board side, so that the first connection terminal having a small occupied area is mounted on the circuit board side. Therefore, it is possible to further increase the degree of freedom in the layout of circuit elements.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view showing an embodiment in which the present invention is applied to a stepping motor type indicating instrument, and FIG.
FIG. 3 is a sectional view of the stepping motor of FIG.
FIG. 4 is a cross-sectional view of the stepping motor of FIG. 1 taken along the line YY. FIG. 4 is a cross-sectional view showing the assembled state of FIG.

In FIG. 1, an indicating instrument is used, for example, as a speedometer of an automobile, and has a pointer 21 having a longitudinal indicating portion 20 and scales, characters, marks, etc. disposed behind the pointer 21. An instrument dial 31 on which the index portion 30 is formed, a diffusion plate 40 made of a translucent material disposed behind the instrument dial 31, and a circuit board 50 disposed behind the diffusion plate 40; A spacer 60 interposed between the circuit board 50 and the diffusion plate 40;
And a relay board 80 disposed behind the stepping motor 70
And the pointer 21 by the stepping motor 70
Is rotated in accordance with the amount of change in vehicle speed, so that it can be read in comparison with the indicator 30 of the instrument dial 31.

The indicating portion 20 of the pointer 21 and the index portion 30 of the instrument dial 31 are formed of a light-transmitting material.
Indicates a plurality of chip-type LEDs mounted on the circuit board 50.
The light emitted from the circuit element 51 composed of a light emitting diode (light emitting diode) shines through the diffusion plate 40, thereby ensuring visibility when the surroundings are dark, for example, at night.

The circuit board 50 also has a round pin-shaped male first connection terminal 52 protruding toward the stepping motor 70.
And a circuit element 53 composed of circuit components constituting a stepping motor 70 drive circuit different from the circuit element 51 composed of an LED.
Are connected to each other through a circuit pattern (not shown) of the circuit board 50.
The connection terminal 52 extends in the axial direction of the drive shaft described later and is electrically connected to the stepping motor 70.

The stepping motor 70 is a so-called PM
(Permanent magnet) type, as shown in FIGS.
A magnet rotor 712 composed of a permanent magnet having a center at the center 11 and two annular stator cores 716 formed by combining a coil 714 wound around an annular bobbin 713 and an annular yoke 715 with a drive shaft 71 of the magnet rotor 712.
An annular stator body 717 concentrically laminated along one axial direction, and a pair of bearing plates 718 fixed to the opening side of the annular stator body 717, respectively, are provided inside the hollow of the annular stator body 717. A magnet rotor 712 is accommodated in each bearing plate 718 and the drive shaft 71 is
1 and the output side of the drive shaft 711 protrudes from the front surface which is one side surface of the annular stator body 717 (stepping motor 70), and supplies a drive signal (voltage) to the coil 714 according to the amount of change in vehicle speed. Thus, the magnet rotor 712 is driven to rotate.

In FIG. 2, one end of the annular bobbin 713 of the lower annular stator core 716 projects radially of the magnet rotor 712 and is electrically connected to each coil 714, and the other end of the drive shaft 711 is A plurality of substantially L-shaped terminals 719 projecting in the axial direction and electrically connected to the relay board 80 are fixed by insert molding.

In FIG. 2, a terminal cover 718 a that covers a terminal 719 protruding from the peripheral surface of the stepping motor 70 is extended from a bearing plate 718 located on one side (front side).

As shown in FIG. 1, the relay board 80 includes a terminal 719 of the stepping motor 70 and a second connection terminal 81.
Are provided with a plurality of through holes 82 for conducting to a circuit pattern (not shown).

As shown in FIGS. 1 and 4, the second connection terminal 81 is a hollow box-shaped female terminal having both ends opened, and a frame 811 extending in the axial direction of the drive shaft 711.
An insertion portion 812 formed in a hollow inner space of the frame portion 811 and a pair of bent elastic portions formed by partially cutting and raising the frame portion 811 so as to protrude into the insertion portion 812. Connection portion 813 and the frame portion 811
And a connecting piece 814 that extends in the axial direction of the drive shaft and is electrically connected to the relay board 80. When the first connection terminal 52 is inserted into the insertion portion 812, the connection portion 813 elastically contacts. , Whereby the first and second connection terminals 5
The electrical connection between the second connection terminal 81 and the circuit pattern of the relay board 80 is achieved by the electrical connection between the second connection terminal 81 and the connection board 814 being achieved by soldering the connection piece 814 to the relay board 80.

In this case, the stepping motor 70
After the terminal 719 and the connection piece 814 of the second connection terminal 73 are inserted into the through-hole 82 of the relay board 80, these penetrating ends are electrically connected behind the relay board 80 by soldering. Further, the terminal 719 and the portion where the connection piece 814 of the second connection terminal 81 is soldered to the relay board 80 are electrically connected to each other by a circuit pattern (not shown). 719
And a conduction path with the second connection terminal 81 is formed.

Next, the assembling of the indicating instrument of this embodiment will be described with reference to FIGS. 1 and 4. The first connecting terminal 52 is connected to the circuit board 50 and the second connecting terminal 81 is connected to the relay board 80. Each of them is soldered and fixed in advance, and the stepping motor 70 is fixed to the relay substrate 80 in advance by penetrating a crimped portion (not shown) formed in the relay substrate 80 and bending the tip thereof. The first connection terminal 52 is soldered to the circuit board 50, and the terminal 719 of the stepping motor 70 and the second connection terminal 8
The soldering to the relay board 80 with the one connection piece 814 can be performed by an automatic soldering line.

Next, the driving shaft 7 of the stepping motor 70
The relay board 80 is attached and fixed to the rear surface (the other side surface) opposite to the front surface (one side surface) on which the protrusion 11 protrudes and is attached to the circuit board 50 in the axial direction of the drive shaft 711.

Next, the driving shaft 7 of the stepping motor 70
The first connection terminal 52 is inserted into the insertion portion 812 of the second connection terminal 81 by placing the circuit board 50 on the front surface from which the protrusion 11 protrudes, passing the drive shaft 711 through the circuit board 50, and inserting the first connection terminal 52 into the insertion portion 812 of the second connection terminal 81. The connection terminal 52 and the second connection terminal 81 are electrically connected, or the front side of the stepping motor 70 having the relay board 80 is arranged behind the circuit board 50 and the second connection terminal 81 Insertion section 812
By inserting the first connection terminal 52 therein, the first connection terminal 52 and the second connection terminal 81 are electrically connected. The connection work (step) between the stepping motor 70 (second connection terminal 81) and the circuit board 50 (first connection terminal 52) can also be performed by an automatic assembly line.

The first connection terminal 5 is provided on the circuit board 50.
2. In addition to the LED (circuit element) 51, a circuit element 53 including the above-described circuit components for controlling a voltage signal to be supplied to the stepping motor 70 (each coil 714) according to the amount of change in vehicle speed is mounted. The circuit element 53 and the first connection terminal 52 are electrically connected to each other via a circuit pattern (not shown). Electrical conduction between the circuit and each coil 714 is performed.

Next, the spacer 60, the diffusion plate 40, and the instrument dial 31 are mounted on the circuit board 50, and
The drive shaft 711 is inserted through the 0, the diffusion plate 40 and the instrument dial 31, and the stepping motor 70, the circuit board 50, the spacer 60, the diffusion plate 40 and the instrument dial 31 are integrally fixed by screws 90.

Next, the pointer 21 is fixed to the tip of the drive shaft 711 protruding from the instrument dial 31 to complete the operation.

As described in detail above, in this embodiment, the stepping motor 70 which rotatably accommodates the magnet rotor 712 having the drive shaft 711 and has at least the output side of the drive shaft 711 protruding from one side surface.
And a circuit board 50 arranged so that the output end of the drive shaft 711 penetrates at a position facing the front surface (one side surface) of the stepping motor 70. A relay board 80 that is electrically connected to the stepping motor 70 is provided on the back (other side) opposite to one side, and the relay board 80 and the circuit board 50 are provided.
And second connection terminals (connection members) 5 for electrically connecting
2 and 81 are disposed outside the stepping motor 70, so that the first and second connection terminals 52 and 8 as connection members are provided.
1 can be set at an arbitrary position, and the degree of freedom in layout of the circuit elements 51 and 53 mounted on the circuit board 50 can be increased.

A connecting member for connecting the circuit board 50 and the relay board 80 is formed by a male first extending member extending in the axial direction of the drive shaft 711.
And the second connection terminal 81 of a female type that can be electrically connected by inserting the first connection terminal 52 into the first connection terminal 52 on the circuit board 50 side. The electrical connection between the stepping motor 70 and the circuit board 50 is achieved by the insertion connection with the second connection terminal 82 on the side of the stepping motor 70, and the connection workability can be improved.

In particular, the male first connection terminal 52 is mounted on the circuit board 50 side, and the female second connection terminal 82 is mounted.
Is mounted on the side of the relay board 80, so that the first connection terminal 52 having a small occupied area is mounted on the side of the circuit board 50, so that the layout flexibility of the circuit elements 51 and 53 with respect to the circuit board 50 is further increased. There is an advantage that can be.

The stepping motor 70 and the relay board 8
In the soldering with 0, the rear side (other side) where the drive shaft 711 of the stepping motor 70 does not protrude becomes the connection surface to the relay board 80, so that the assembling by the automatic soldering line becomes possible, and the work efficiency is improved. Can be increased.

The structure of the stepping motor 70 does not change between the case where the circuit board 50 is arranged on the front (one side) and the case where the circuit board 50 is arranged on the back (other side). Can be shared, and costs can be reduced.

In this embodiment, the first connection terminal 52 is formed as a rod-shaped male type, while the second connection terminal 81 is formed as a substantially box-shaped female type into which the first connection terminal 52 can be inserted and connected. However, if the first and second connection terminals 52 and 81 can be inserted and connected to each other, the second connection terminal 81 is made male and the first connection terminal
May be formed in a female type.

Further, the structure of the first and second connection terminals 52 and 81 is not limited to the male type and the female type as described above, but extends in the axial direction of the drive shaft 711. These shapes or structures can be arbitrarily set as long as electrical connection can be achieved by inserting one side into the other side. For example, the first and second connection terminals 52 and 81 The insertion side may be formed in a flat plate shape.

The connection member is not limited to the one that is electrically connected by inserting one side into the other side as described above, as long as the connection member is arranged outside the stepping motor 70. As long as the member is capable of electrically connecting the relay board 50 and the relay board 80, for example, an electric cord or a single terminal extending between the boards can be applied.

[0039]

As described above in detail, the present invention relates to a stepping motor having a magnet rotor having a drive shaft rotatably accommodated therein and having at least an output side of the drive shaft protruding from one side, and a stepping motor having the same. A connection structure of a stepping motor for electrically connecting a circuit board disposed so that an output side end of the drive shaft penetrates at a position facing one side surface, and one side surface of the stepping motor. A relay board electrically connected to the stepping motor is provided on the other side opposite to the axial direction of the drive shaft, and the stepping motor and the circuit board are electrically connected between the relay board and the circuit board. The stepping motor and the circuit are provided by providing a connecting member connected to the Even when conducting connecting the plate through the relay substrate can provide a connecting structure of a stepping motor capable of increasing the layout flexibility of the circuit elements.

Also, in the present invention, the connecting member may include a pair of connecting terminals electrically connected to each of the circuit board and the relay board, and one side of the connecting terminals may extend in the axial direction of the drive shaft. The connection workability can be improved because the other side is a female second connection terminal that can be electrically connected by inserting the first connection terminal.

Further, the first connection terminals are mounted on the circuit board side, and the second connection terminals are mounted on the relay board side, so that the layout flexibility of the circuit element can be further increased.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an indicating instrument using a stepping motor according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the stepping motor of FIG. 1 taken along line XX.

FIG. 3 is a sectional view of the stepping motor of FIG. 1 taken along the line YY.

FIG. 4 is a sectional view showing an assembled state of the indicating instrument of FIG. 1;

FIG. 5 is a sectional view showing a conventional example.

FIG. 6 is a sectional view showing a conventional example.

[Explanation of symbols]

 Reference Signs List 50 circuit board 51, 53 circuit element 52, 81 first and second connection terminals (connection members) 70 stepping motor 80 relay board 711 drive shaft 712 magnet rotor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02K 37/00-37/24

Claims (3)

(57) [Claims] 1. A stepping motor which rotatably accommodates a magnet rotor having a drive shaft and projects at least an output side of the drive shaft from one side surface, and the drive shaft at a position facing one side surface of the stepping motor. A connection structure of a stepping motor for electrically connecting a circuit board disposed so that an output side end of the stepping motor penetrates, and a side of the stepping motor opposite to one side in the axial direction of the drive shaft. A connection board for electrically connecting the stepping motor to the stepping motor, and a connection member for electrically connecting the relay board and the circuit board arranged outside the stepping motor. . 2. The male first terminal, wherein the connection member comprises a pair of connection terminals electrically connected to each of the circuit board and the relay board, and one of the connection terminals extends in the axial direction of the drive shaft. And the other side is the first terminal.
2. The stepping motor connection structure according to claim 1, comprising a female second connection terminal that can be electrically connected by inserting said connection terminal. 3. The stepping motor connection structure according to claim 2, wherein the first connection terminal is mounted on the circuit board side, and the second connection terminal is mounted on the relay board side. .