JPH086833B2 - Electric control valve - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric control valve for controlling the state quantity of a fluid used outdoors or in a high humidity atmosphere.

2. Description of the Related Art Conventionally, there is an electric control valve of this type as shown in FIG. In FIG. 2, 4 is 2 for one inflow port 1.
The valve body 5 is driven by a motor 6, which is a ball valve that switches the outflow direction to the two outflow ports 2 and 3. The motor 6 is covered with a case 7, and is fixed by sandwiching a motor mounting base 8 and a packing 9 so that water does not get in from the upper part and get wet. A ventilation hole 11 is provided in the lower bottom part of the electrical equipment part 10 covered with the case 7, and an electric wire 12 extending from the motor 6 is fixed to the case 7 by brushing 13.
It is also sealed so that water does not enter from the vicinity.

Problems to be Solved by the Invention In such a conventional configuration, water does not enter from the outside of the electrical component unit 10 , but after the operation, the atmospheric temperature in the electrical component unit 10 rises, and then in the process of being cooled by the outside air. Condensation may occur on the inner surface of the electrical equipment case 7, and there is a risk that the motor 6 or the like may break down or enter an unsafe state due to intrusion of condensed water droplets. The present invention solves such a conventional problem, and an object thereof is to provide an electric control valve which is safe and has excellent durability without dew condensation even in a high humidity atmosphere.

Means for Solving the Invention In order to solve the above problems, an electric control valve of the present invention is
A control valve for controlling the state quantity of the fluid, a drive device for electrically driving the control valve, an electrical equipment case for covering the electrical equipment part including the drive device, and a heating element provided in the electrical equipment case. I am configuring.

With the above-described configuration, the present invention keeps the ambient temperature in the electrical equipment case at the dew point temperature or higher by the heating element provided in the electrical equipment case, and prevents dew condensation in the electrical equipment case.
By improving the reliability of electrical components, it has become an electrically controlled valve with excellent durability.

Embodiment An embodiment of the electric control valve of the present invention will be described with reference to the accompanying drawings. In FIG. 1, the inflow path 13 and the first outflow path
14, a second outflow passage 15, and a first valve seat 16 and a second valve seat 17 are provided in the openings facing the two outflow passages 14 and 15, and correspond to the two valve seats 16 17 respectively. A first valve body 19 and a second valve body 20 having a rubber packing 18 are slidably provided on a shaft 21. A spring 22 is provided between the two valve bodies 19 and 20, and is biased in a direction in which they are separated from each other, that is, in a direction in which both valve bodies 19 and 20 abut the corresponding valve seats 16 and 17.

A first stopper 23 and a second stopper 24 for limiting the sliding range of the valve bodies 19, 20 urged in one direction on the shaft 21 are provided, and the distance between the two valve bodies 19, 20 is provided. Are regulated. The distance between the two valve seats 16 and 17 is made slightly smaller than the maximum distance between the two valve bodies 19 and 20 regulated by the two sweepers 23 and 24, so that the two outflow passages 13 and 14 are formed.
A width at the position of shaft 21 where
The urging force of is sufficiently added as the contact force of the valve elements 19 and 20 to the valve seats 16 and 17, and the closing ability is stabilized. When the shaft 21 is further moved from the position where the two outflow passages 13 and 14 are both closed to the direction in which the valve body 19 abuts on the valve seat 16, the second stopper 24 moves the valve body 20 from the valve seat 17 to the valve seat 17. Exit, second outflow path 15
The side opens. On the other hand, when the shaft 21 is thrust in the opposite direction from the both closed positions, the first outflow passage 14 side is opened. The shaft 21 of the control valve 25 configured as described above uses a motor 27 that is an electric drive device 26, and the motor 27 has a screw portion 28 provided on the shaft 21 and a fixed nut portion 29 fixed to the main body. The forward and reverse rotations of (3) are thrust-driven while rotating the shaft 21 via the gear 30. Further, a cam 33 is provided on the rotating shaft 32 of the motor 27 as the position detection switch 31 of the shaft 21,
Three microswitches 34, each of the first outflow path
The cam 33 operates the micro switch 34 at the fully open position of 14 and the fully open position of the second outflow passage 15, both of which are fully open.

The electric equipment part 35 such as the motor 27 which is the drive device 26 and the micro switch 34 which is the detector 31 has a rainproof structure (a structure in which water does not intrude from above or from the side) by the electric equipment case 36. The case 36 is provided with a heating element (heater) 37 for self-control so as to keep the ambient temperature constant at a predetermined temperature (40 to 50 ° C.), and a small hole 38 is formed in the lower bottom of the electrical equipment case 36. It is provided.

With the above configuration, since the inside of the transmission case 36 is always kept at the dew point temperature or higher, dew condensation does not occur, that is, the heating element 37 has a role of protecting the electrical component part 35 against moisture, and thus has high reliability. Can be obtained. In addition, since the small hole 38 is provided, the inside of the electrical equipment case 36 can breathe with the outside air, and at the same time, if water enters due to the deterioration of the case 36, the water will escape from the small hole 38 and the electrical equipment case 36 The structure prevents water from accumulating, further improving the reliability of the electrical component section 35 .

Effects of the Invention As described above, according to the electric control valve of the present invention, the following effects are obtained.

(1) Since the heating element is provided in the case that protects the electrical component, the electrical component is protected from moisture and water droplets, and reliability is improved.

(2) Since the heating element is provided, the electrical component is kept at a predetermined temperature even when the outside air temperature is 0 ° C. or less, such as in winter, and operates stably regardless of the season or the climate.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an electric control valve of the present invention,
FIG. 2 is a sectional view of a conventional electric control valve. 25 ...... Control valve, 26 ...... Drive device, 35 ...... Electrical equipment part, 36 ......
Electrical equipment case, 37 ... Heating element.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuyoshi Ueda 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Riteru Miyoshi 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (56) References Japanese Unexamined Patent Publication No. 52-102949 (JP, A) Actual development No. 64-14973 (JP, U)

Claims (3)

[Claims] 1. A control valve for controlling a state quantity of a fluid, a drive device for driving the control valve, an electric equipment case for covering an electric equipment part including the drive device, and an electric equipment case provided in the electric equipment case. An electric control valve with a heating element and a small hole in the electrical equipment case. 2. The electric control valve according to claim 1, wherein the electrical component section includes a drive device and a detector for detecting the valve position of the control valve. 3. The electric control valve according to claim 1, wherein the heating element is a self-control type heater that keeps the ambient temperature in the electrical equipment case constant at a predetermined temperature.