JP3767243B2 - Motor control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inverter device provided with an inverter circuit and a motor control device such as a servo controller.
[0002]
[Prior art]
In various industrial equipment, rotation control of a motor as a drive source is controlled by a motor control circuit, and an example of the inverter device will be described with reference to the drawings.
[0003]
In FIG. 4, the inverter device includes a radiator 41, a casing 42, a circuit board 43, a power module 44, and the like. Has been implemented.
[0004]
[Problems to be solved by the invention]
If a voltage doubler (200 V for a device designed with an input voltage of 100 V) is accidentally applied to the input terminal of the conventional inverter device, an overvoltage exceeding the rated voltage is applied to the smoothing electrolytic capacitor. In some cases, the pressure valve is actuated by an increase in the pressure inside the electrolytic capacitor, and the electrolytic solution therein is scattered outside.
[0005]
At this time, if a spark or the like occurs in the circuit part for any reason, the electrolyte solution may be ignited, and the vent part (open hole) of the electrolytic capacitor remains open so that it remains inside the electrolytic capacitor. There was a risk that if the fire broke into the electrolyte, it continued to burn until the electrolyte ran out, leading to a fire.
[0006]
The present invention solves the above-described problems, and an object thereof is to provide a motor control device that is highly safe against a capacitor fire.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is a motor control device in which a flame-retardant thin plate having an elastic structure is sandwiched between an upper vent portion of an electrolytic capacitor and a housing inner wall facing the electrolytic capacitor.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In order to solve the above-described problems, the present invention provides a motor control device having a smoothing electrolytic capacitor in a housing, and is difficult to provide an elastic structure between the upper vent portion of the electrolytic capacitor and the housing inner wall facing the electrolytic capacitor. This is a motor control device that sandwiches a flammable thin plate.
[0009]
The motor control device according to claim 1, wherein an aramid pulp (flame retardant paper) is used for the flame retardant thin plate and an elastic structure is formed by bending .
[0010]
In this way, since the flame retardant thin plate has an elastic structure, the electrolytic solution remaining inside the electrolytic capacitor is held down even if there is a fire inside and outside, holding down the vent top of the electrolytic capacitor and can continue to burn. It has a fire extinguishing action that cannot be done.
[0011]
Moreover, if an aramid pulp is used for a flame-retardant thin plate, an elastic structure can be realized by a simple bending process.
[0012]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0013]
1 and 2, an inverter device 10 as an example of a motor control device includes a radiator 11, a housing 12, a circuit board 13, a power module 14, and the like. An electronic component such as a capacitor 15 is mounted, and a flame-retardant thin plate 17 is sandwiched between the electrolytic capacitor 15 of the casing 12 and the casing inner wall 16 facing the casing.
[0014]
In order to obtain an elastic force, the flame retardant thin plate 17 is bent to the housing inner wall 16 side, and a bent portion 22 is bent so as not to be displaced from the outer periphery of the electrolytic capacitor. Are provided in a direction orthogonal to each other. Then, the bent portion 21 is brought into contact with the inner wall portion 16 of the casing, the bent portion 22 is applied to the outer periphery of the electrolytic capacitor 15, and the elastic force of the flame retardant thin plate 17 is used so that it can be sandwiched.
[0015]
FIGS. 3A and 3B show the state before and after the vent upper portion 18 is opened due to the internal pressure of the electrolytic capacitor increasing. At the moment when the vent upper portion 18 is opened, the internal pressure is Since it becomes very large, the yield strength of the bent portion 21 is lost and the flame-retardant thin plate 17 is deformed. At this time, however, as described above, the flame-retardant thin plate 17 is given elastic force, and the bent portion 21 returns to its original state, and the flame-retardant thin plate 17 again presses the vent upper portion 18 of the electrolytic capacitor 15. That is, there is a fire extinguishing action (suffocation fire extinguishing) that can be shut off from the outside by the flame retardant thin plate 17 even if there is fire 19 inside and outside and the electrolytic solution remains in the electrolytic capacitor 15.
[0016]
In addition, as an example of a flame-retardant thin plate, if an aramid pulp (flame retardant paper) having a thickness of about 0.5 mm is bent, an elastic force can be obtained and realized at low cost. Further, a flame retardant resin may be injection molded. Further, although two electrolytic capacitors have been described, the same can be applied to any number of capacitors.
[0017]
【The invention's effect】
As is clear from the above embodiments, according to the present invention, it is possible to provide a motor control device that is highly safe against a capacitor fire at low cost, and it is difficult even if an abnormal voltage is applied and the electrolytic capacitor bursts. It has a special effect called fire extinguishing action that shuts off the fire with the elastic force of the thin sheet.
[Brief description of the drawings]
FIG. 1 is an internal structural view of an inverter device according to an embodiment of the present invention. FIG. 2 is a perspective view of a flame retardant thin plate according to an embodiment of the present invention. Explanatory drawing of electrolytic capacitor (b) Explanatory drawing of electrolytic capacitor firing of the present invention [FIG. 4] Structural diagram of conventional inverter device [Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Motor controller 12 Case 15 Electrolytic capacitor 16 Case inner wall part 17 Flame-retardant thin plate 18 Vent upper part

Claims (2)

  A motor control device comprising a smoothing electrolytic capacitor in a housing, wherein the flame retardant thin plate having an elastic structure is sandwiched between the vent upper portion of the electrolytic capacitor and the housing inner wall facing the electrolytic capacitor. The motor control device according to claim 1, wherein aramid pulp (flame retardant paper) is used for the flame retardant thin plate and an elastic structure is formed by bending .

Images