JPH11210911A - Motor-operated valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure cutting off the moisture infiltrating into a motor from the lead wire of a motor-operated valve opened or closed by the motor. SOLUTION: This motor-operated valve 1 is constituted of a motor section 11 and a valve section 12 provided at the lower section of the motor section 11. The motor section 11 is provided with a cylindrical can 10 and a stepping motor 13 stored in the can 10, the stepping motor 13 is constituted of a stator 20, a rotor 22 arranged on its inside and a lead wire 80 feeding a pulse signal to the stepping motor 13, and the lead wire 80 is extended to the outside of the can 10 through the can 10. The outside of the can 10 is covered with a resin molding 70 for waterproofing, and the lead wire 80 is molded along the can 10 and is assembled in the molding 70. The lead wire 80 has a core wire 82 in a cover layer 84, and the core wire 82 is impregnated with a sealant to prevent the infiltration of moisture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor-operated valve used in a refrigeration cycle, and more particularly to a structure of a motor lead wire constituting the motor-operated valve.

[0002]

2. Description of the Related Art Conventionally, as a motor-operated valve, for example, a stepping motor is housed in a sealed container, and a valve stem having a threaded portion is driven by an output shaft of the motor to provide a valve seat provided on a valve body. The valve element and the orifice are in contact with the refrigerant, but the valve stem is covered with bellows etc., so that the refrigerant enters the motor side. A structure for preventing such a phenomenon is known from Japanese Patent Application Laid-Open No. 4-228894. In this case, the case housing the motor, i.e., the outside of the can, is covered with a molded resin material to prevent intrusion of moisture and the like contained in the outside air, and a lead wire for driving the motor is integrally formed in the resin. Molded to The lead wire passes through the can and is connected to the motor stator.

[0003]

The lead wire connected to the motor has a structure in which a core wire as a conductor is covered with a resin or the like. The core wire has a structure in which small-diameter conductive wires are twisted, and has a structure that can withstand bending. Therefore, a fine space exists inside the core wire, and a fine space also exists between the core wire and the coating.

[0004] Since the portion of the can close to the main body is cooled by the circulation of the refrigerant by the operation of the motor disposed inside the can, dew condensation occurs inside the can. When this condensation occurs, the moisture contained in the outside air further enters the inside of the can through the minute space of the lead wire of the motor, resulting in condensation.
As described above, external moisture enters the can by the so-called respiratory action and dew forms. This causes a problem caused by the condensed moisture, and adversely affects the motor. The present invention has been made in view of such a problem, and an object of the present invention is to provide a motor-operated valve using a motor that eliminates a problem caused by intrusion of moisture into the motor. .

[0005]

In order to achieve the above object,
The motor-operated valve according to the present invention includes a motor unit having a stepping motor including a rotor and a stator housed in a can, penetrating the can from the stepping motor, and having a lead wire extending outside the can, and the motor unit. In a motor-operated valve comprising a driven valve portion, a core wire constituting the lead wire is sealed with a sealant.

In the motor-operated valve according to the present invention having the above-described structure, the moisture entering through the micro space formed in the core of the lead wire is closed by the sealant. Thereby, the intrusion is stopped, and the trouble of the motor and the electric valve caused by the dew condensation caused by the invasion of moisture can be solved.

[0007]

FIG. 1 is an explanatory view showing a sectional structure of a motor-operated valve according to an embodiment of the present invention. Code 1 for the whole
The motor-operated valve indicated by is composed of a motor unit 11 and a valve unit 12 provided below the motor unit 11. The motor unit 11 has a cylindrical can 10 and a stepping motor 13 housed in the can 10. The stepping motor 13 includes a stator 20 and a rotor 22 positioned inside the stator 20. And a lead wire 80 for supplying
0 to the outside of the can 10. Can 10
Is covered with a resin molding 70 to be waterproof, and the lead wire 80 is molded along the can 10 and is integrated into the molding 70. The lower surface of the can 10 is closed by a cover 14, and a valve body 40 constituting the valve section 12 is attached via a bush 15 provided on the cover 14.

The motor shaft 24 attached to the rotor 22 drives the pinion 30, and the gear 32 meshing with the pinion 30 rotates the drive shaft 36 via the driver 34. The drive shaft 36 is screwed into a screw portion formed on the valve body 40, and the drive shaft 36 converts a rotary motion into a linear motion to move the valve shaft 42 up and down. A valve body 44 is attached to the tip of the valve shaft 42, and adjusts an opening degree of a flow path between the valve body 44 and a valve seat 50 provided on the valve body 40.

The valve body 40 is connected to two pipes 52 and 54 that communicate with the refrigerant inlet and outlet. One end of a bellows 48 is attached to the valve shaft 42.
Is attached to a ring 46 fixed to the valve body 40. The bellows 48 has a function of preventing the refrigerant from entering the motor side while allowing the valve shaft to move up and down.

FIG. 2 shows the structure of a lead wire according to the gist of the present invention. The lead wire has a core wire 82 and a coating layer 84 made of an insulating plastic material covering the core wire 82. Connected to coil. Since the core wire 82 is composed of a large number of small-diameter conductors, there is a gap between the conductors. There is also a minute gap between the core wire 82 and the coating layer 84. When the lead wire 80 is buried in the molding 70 as it is, a phenomenon in which moisture in the air penetrates into the inside of the can through the minute space inside the lead wire 80 and condenses according to a temperature change inside the can 10. Occurs.

However, in the embodiment of the present invention, FIG.
Of the lead wire 80 shown in FIG.
100 ”), the minute space formed in the core wire 82 is filled with a sealant, and the minute space is closed. The impregnation of the core wire 82 with the sealant is performed by immersing the lead wire 80 having a predetermined length in a liquid of the sealant. Thereby, the core wire 82 and the coating layer 84
Is also closed by the sealant. Thus, penetration of moisture from the outside to the motor side through the fine space formed in the core wire 82 is prevented, and the core wire 82 is sealed with the sealant.

That is, assuming that the lead wire 80 is connected to a power supply outside the motor-operated valve, the moisture contained in the outside air will be transmitted to the motor side through the minute space formed in the core wire 82. However, the core material 82
Since the minute space inside is closed, moisture cannot enter the motor side. The core wire 82 of the lead wire 80
Moisture that enters between the coating layer and the coating layer 84 is also restrained by the sealant.

[0013]

As described above, according to the present invention, the core of the lead wire connected to the motor constituting the motor-operated valve used in a high humidity environment or the like is sealed with a sealant, and the fine wire formed inside the core wire is formed. By closing the space, moisture entering from the outside can be blocked, moisture proof and waterproof can be achieved, and problems can be prevented from occurring in the electric valve.

[Brief description of the drawings]

FIG. 1 is a sectional view of a motor-operated valve according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a structure of a lead wire shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 motorized valve 10 can 20 stator 22 rotor 24 output shaft 36 screw rod 40 valve body 44 valve body 50 valve seat 70 resin molding 80 lead wire 82 core wire

Claims (1)

[Claims] 1. A stepping motor comprising a rotor and a stator is accommodated in a can, a motor section having a lead wire extending from the stepping motor through the can and extending outside the can, and driven by the motor section. An electric valve comprising a valve portion, wherein a core wire constituting the lead wire is sealed with a sealant.