JPH07131954A - Governer mechanism of fan motor for heat exchanger - Google Patents

Abstract

PURPOSE:To stop power supply for motor drive only when the high speed rotating condition is achieved by utilizing a bimetal or shape memory alloy which deforms under a high temperature condition into a pressing body of a switch. CONSTITUTION:One end of a plate spring 3 consisting of a thermostat is fixed to a base portion 12 of a govener body 11 and a weight 4 is fixed in the external side of the other end. A pressing body 5 is formed of such spring 3, weight 4 and base portion 12. The spring 3 is formed, for example, of a bimetal and it is curved, when temperature rises, toward the switch 6 provided on the governer body 11 depending on the temperature. Therefore, the higher the temperature around the governer mechanism 7 rises, the more the spring 3 is inclined toward the switch 3. Thereby, an energizing force of the spring 3 increases and the switch 6 can be turned OFF only at a higher number of rotations. Thereby, the higher the temperature inside the engine room, the more wind forming force of the fan 8 is increased, accelerating the thermal exchange.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a governor mechanism for a fan motor for a heat exchanger, which has a constant speed of the fan motor depending on whether the temperature inside the engine room where the heat exchanger is installed is high or low. The present invention relates to one configured to change the rotation speed.

[0002]

2. Description of the Related Art A conventional governor mechanism for a fan motor for a heat exchanger is a mechanical type as a control device for keeping the rotation speed of a DC motor constant, and is composed of a weight and a switch that rotate together with a rotor. ing. When the rotation speed of the rotor increases, the weight is moved to the outer circumference by the centrifugal force, so that the switch is turned off, the current flowing through the winding of the motor is cut off, the rotation speed of the rotor is reduced, and it is kept constant. Such a conventional governor mechanism is configured to always maintain a constant rotation speed even when the engine room has a high temperature in summer or the like and has a low temperature other than that.

[0003]

However, when the temperature inside the engine room is high, the heat exchange of the heat exchanger is reduced by that amount, so it is preferable to increase the rotation speed of the fan above normal. Therefore, in the present invention, the constant governor speed to be controlled in the mechanical governor mechanism is set to increase as the temperature rises, and the following constitution is adopted to achieve the object.

[0004]

A governor mechanism for a fan motor for a heat exchanger according to the present invention comprises a pressing body 5 having a weight 4 with a spring 3 which rotates together with a rotating shaft 2 of the fan motor 1,
When the rotation shaft 2 is less than a certain rotation, the pressing force of the spring 3 keeps the pressing body 5 in the ON position to apply a driving force to the motor 1, and when the rotation shaft 2 exceeds the certain rotation, the weight 4 is centrifuged. In a governor mechanism 7 of a fan motor for a heat exchanger, which includes a switch 6 for turning the pressing body 5 to an OFF position to lose the driving force against the biasing force by a force, a bimetal or a shape memory that deforms at a high temperature. When an alloy is used for the pressing body 5 and the operating temperature is high,
It is characterized in that it is configured so that the limit of the constant number of rotations of the pressing body 5 in the OFF state is increased.

[0005]

According to the governor mechanism of the present invention, when the temperature around the fan is high, the bimetal or the shape memory alloy is deformed, and the pressing position of the pressing body is deviated more greatly on the switch side than when the temperature is low. To be done. As a result, the motor drive power supply is stopped only when the rotation speed is higher than that at the time of low temperature. Therefore, the higher the temperature, the greater the electromotive force of the fan, which promotes heat exchange.

[0006]

Embodiments of the present invention will now be described with reference to the drawings. The drawing is an explanatory perspective view of a fan and a motor having the governor mechanism. In this embodiment, a rotary shaft 2 is provided so as to project from one end of a fan motor 1, and a governor body 11 is fixed to the rotary shaft 2. A switch 6 and a base 12 are fixed to the governor body 11, one end of a plate-shaped spring 3 made of a thermostat is fixed to the base 12, and a weight 4 is fixed to the outside of the other end. The spring 3, the weight 4 and the base 12 form a pressing body 5. Further, the tip end surface of the pressing body 5 is pressed against the movable piece of the switch 6. Then, when the governor body 11 rotates with the rotation of the rotating shaft 2, a centrifugal force acts on the weight 4 displaced on the periphery thereof, and when the number of rotations exceeds a certain value, the biasing force of the spring 3 is overcome and the spring 3 is moved. It is deformed to the outside, and when it is separated from the movable piece of the switch 6, the switch is placed in the OFF state, and the power supply to the fan motor 1 is stopped.

In this embodiment, the spring 3 is made of bimetal, and the spring 3 is bent toward the switch 6 when the temperature rises.
Therefore, as the temperature of the peripheral edge of the governor mechanism 7 rises, the spring 3 tilts toward the switch 6 side, and the urging force of the spring 3 increases, so that the switch 6 becomes OF only at a higher rotational speed.
It can be in the F state. A hole 10 formed in the central portion of the boss portion 9 of the fan 8 is inserted into the rotary shaft 2 so that the rotary shaft 2 and the fan 8 are fixed and prevented from falling off by appropriate means. In the fan 8, a plurality of blade portions 13 are integrally formed on the outer periphery of the boss portion 9 in the radial direction so as to project. Then, it is arranged on the front surface side or the rear surface side of the core of the heat exchanger (not shown), and its rotation blows air to the heat exchanger core to cool high-temperature engine cooling water or the like flowing in the tube of the core, thereby performing heat exchange Is to do.

[0008]

[Modification] Instead of forming the spring 3 from a bimetal in the above embodiment, it may be formed from a shape memory alloy. Then, when the temperature exceeds a certain temperature, the switch 6
It is deformed to the side, the biasing force of the spring 3 is increased, and the switch 6 is turned off.
The number of rotations in the F state is set to be higher than usual.

[0009]

The governor mechanism of the fan motor for a heat exchanger according to the present invention uses a bimetal or a shape memory alloy that deforms at a high temperature for the pressing body 5 of the switch 6 so that the switch for driving the motor can be operated at a high temperature. It is possible to drive the rotational speed to a higher limit than usual. This can promote heat exchange when the temperature inside the engine room is high. Also, at low temperatures, the upper limit of the rotation speed of the fan motor is set lower than that at high temperatures to avoid unnecessary rotation of the fan at high speed, and to reduce fan power.
It can be highly durable.

[Brief description of drawings]

FIG. 1 is an explanatory perspective view of a fan and a motor having a governor mechanism of a heat exchanger fan motor of the present invention.

[Explanation of symbols]

 1 Fan Motor 2 Rotating Shaft 3 Spring 4 Weight 5 Pusher 6 Switch 7 Governor Mechanism 8 Fan 9 Boss 10 Hole 11 Governor Main Body 12 Base 13 Wing

Claims (1)

[Claims] 1. A pressing body 5 having a weight 4 with a spring 3 that rotates together with a rotating shaft 2 of a fan motor 1, and a pressing body 5 by a biasing force of the spring 3 when the rotating shaft 2 is below a certain rotation. A driving force is applied to the motor 1 while keeping it in the ON position, and the centrifugal force of the weight 4 resists the biasing force by the centrifugal force of the weight 4 to set the pressing body 5 to the OFF position and the driving force. Switch 6
In a governor mechanism 7 for a fan motor for a heat exchanger, the bimetal or shape memory alloy that deforms at a high temperature is used for the pressing body 5, and when the operating temperature is high, the pressing body 5 is in the OFF state. A governor mechanism for a fan motor for a heat exchanger, which is configured so that a limit of a constant rotation speed is increased.