JP2543245Y2 - Insulated resistor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated resistor used for a motor drive unit for controlling a motor.

[0002]

2. Description of the Related Art FIG. 4 is a diagram showing an example of a circuit of a motor drive unit for controlling a motor of a machine tool. A three-phase AC R, S, T is input to a rectifier circuit 2 via an electromagnetic switch 1. You. The power supply converted to DC by the rectifier circuit 2 is smoothed by a smoothing capacitor 3 and sent to a switching circuit (transistor) 4. Then, the electric motor is driven by the power supply that has been converted into three-phase AC again by the switching circuit (transistor) 4. If the control becomes impossible or the switching circuit (transistor) 4 is destroyed due to an accident or the like, the electromagnetic switch 5 is immediately turned off, and the U, V, W
The phases are short-circuited by the resistors R3, R4, R5 so that the short-circuit current will brake the motor. The electromagnetic switch 5 may be interlocked with the electromagnetic switch 1 in some cases.

FIG. 5 is a perspective view showing a mounting example of a conventional motor drive unit. In particular, a switching circuit (transistor) 4 and a rectifier circuit 2 which require heat radiation are mounted on a heat radiation fin 6 which is a part of a housing. Have been. The electrical connection between the switching circuit (transistor) 4 and the rectifying circuit 2 is made by screwing the printed circuit board 7. Other components are fixed and electrically connected to the printed circuit board 7 by soldering.

[0004]

The above-mentioned resistor of the motor drive unit has a short operating time and thus does not generate continuous heat, but requires a large surge resistance. However, there is no large-capacity resistor fixedly and electrically connected to the board by soldering. Therefore, a plurality of resistors must be mounted depending on the capacity of the motor. Therefore, the space on the substrate is wasted, and there is a limit to miniaturization of the motor drive unit. Further, when the motor is changed, it is necessary to change the resistance value of the resistor depending on its capacity, characteristics, and the like. However, since the resistor is soldered, there is a problem that it is not easy to replace the resistor.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an insulated resistor that can efficiently use a space on a substrate and that can be easily mounted and replaced.

[0006]

The present invention relates to a printed circuit board used for a motor drive unit for controlling an electric motor .
Equipped with multiple screwed external terminals that can be mounted
The present invention relates to an insulated resistor in which the external terminals are arranged on the same plane , and the object of the present invention is to provide a mounting hole for mounting a package made of a synthetic resin directly on the package. This is achieved by providing

[0007]

In the present invention, the package is made of synthetic resin and can be screwed to the housing, and the board can be screwed to the external terminals, so that the space on the board is not wasted. , Mounting and replacement are easy.

[0008]

FIG. 1 is a perspective view showing an example of an insulated resistor according to the present invention, in which a resistor is housed in a synthetic resin package 11 of the insulated resistor 10. FIG. An external terminal 13 having a screw hole 12 for mounting the printed circuit board with a screw is provided at an upper portion of the package 11, and a mounting hole 14 for mounting the housing to the housing with a screw or the like is provided at a lower portion of the package 11. Pins 15 are provided on the mounting surface of the package 11 to the housing, and are inserted into holes provided in the housing to be used for positioning when mounting the housing. The mounting surface of the printed circuit board and the mounting surface of the housing are formed parallel to each other.

FIG. 2 is a perspective view showing a mounting example of a motor drive unit using the above-mentioned insulated resistor 10 corresponding to FIG. 5, and FIG.
FIG. 4 is a partial cross-sectional view when screws are screwed. The conventional resistors R3, R4, R5 are removed from the printed circuit board 7, and the insulated resistor 10 of the present invention is mounted on the radiating fins 6. The electrical connection of the insulated resistor 10 is made by screwing the printed circuit board 7. At this time, the insulating resistor 10 must be mounted on the radiating fin 6 with high accuracy.
Since accurate positioning can be performed without the need for a special jig or the like simply by adjusting the pins 14 to 7, the work can be easily performed without considering the mounting accuracy.

A hole may be formed in the insulated resistor 10 and a pin may be provided in the radiation fin 6. Also,
The external terminals 13 may be made to protrude from the housing mounting surface area of the package 11 so as to cover the adjacent switching circuit (transistor) 4 and the like, so that the space on the heat radiation fins 6 can be used effectively.

[0011]

As described above, according to the insulated resistor of the present invention, the space on the substrate can be used efficiently, so that the size of the motor drive unit can be reduced, and mounting and replacement can be achieved. Since the work is easy, the number of man-hours can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of the insulated resistor of the present invention.

FIG. 2 is a perspective view showing a mounting example of a motor drive unit using the insulated resistor of the present invention.

FIG. 3 is a partial cross-sectional view when the motor drive unit of FIG. 2 is screwed.

FIG. 4 is a diagram illustrating an example of a circuit of a motor drive unit that controls an electric motor of a machine tool.

FIG. 5 is a perspective view showing a mounting example of a conventional motor drive unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Insulation type resistor 11 Package 12 Screw hole 13 External terminal 14 Mounting hole 15 Pin

Claims (3)

(57) [Scope of request for utility model registration] 1. A plurality of screws which can be attached to a printed circuit board used for a motor drive unit for controlling an electric motor.
Equipped external terminals, and these external terminals
An insulated resistor provided on a surface , wherein the package is made of a synthetic resin, and the package is provided with a mounting hole for directly attaching the package to a housing. 2. The insulated resistor according to claim 1, wherein a pin or a hole for mounting positioning is provided on a mounting surface of the package to the housing. 3. The insulated resistor according to claim 1, wherein the external terminals protrude from an area of a mounting surface of the package to the housing.