JPS62215184A - Shield method for electric expansion valve motor - Google Patents

Abstract

PURPOSE:To shield both a motor and a lead cable concurrently and monolithically by forming a projection to make a space between the internal surface of a mold and the motor. CONSTITUTION:A projection 30 made in a mold 24 works as a spacer forming a space between a motor part 2 and the surrounding wall 25 and the bottom wall 26 of the mold 24, when the motor part 2 is housed in the recess 28 of the mold 24 inversely. On the other hand, a side passage 29 is formed on one side of the mold 24, continuous to the recess 28 and corresponding to a lead cable 9, while forming a part of the recess 28. By pouring a molten insulation material into the space within the mold 24, the motor part 2 and the lead cable 9 can be concurrently shielded and it becomes possible to obtain a shield material 22 for covering the motor part 2, and a side part 23 swelling outside from one side of said shield material 22 and covering the lead cable 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method of coating a motor part of an electric expansion valve used in a refrigeration cycle.

(b) Conventional technology Publication No. 142834/1983 (66 people 83) discloses three combustible parts each having a recess for accommodating an expansion valve and a guide portion for a conduit connected to the expansion valve. A heat insulating cover for an expansion valve is disclosed, which is characterized in that at least one part is provided with an adhesive, and other parts are adhered to the part to cover the expansion valve.

(c) Problems to be Solved by the Invention According to the above-mentioned conventional technology, when covering the expansion valve, the three flexible parts are manually pasted together with adhesive, so the two parts are glued together. In addition, since the capillary tube extends outside from between the two parts, a gap is formed between the capillary tubes, and moisture gradually leaks into the cover from this gap. A problem has arisen in that ice blocks are formed around the expansion valve, causing the expansion valve to malfunction.

B) Means for Solving the Problems In order to solve the above problems, the present invention houses a stepping motor (6) in a case (4) and includes a leader line (9) extending from the stepping motor to the outside. When covering the motor part (2) of the electric expansion valve (1) consisting of the motor part (2) and the valve body (3), both the peripheral wall (B) and the bottom wall (E) are covered. A recess defined by While preparing a casting mold (24) equipped with a side channel (c), an annular anti-rust coating surface Gυ is formed in advance at a suitable location of the case (4) in contact with the protrusion, and a drawer is formed on the motor section. line (9)
With the motor part (2) temporarily fixed, turn it upside down and store the lead wire in the recess corresponding to the side path □□□ to fill the space between the peripheral wall and bottom wall and the motor part. A method for covering a motor part (2) of an electric expansion valve (1) in which a molten insulating material is poured and solidified to form a covering part (22) that covers the motor part (2) and a leader wire (9). provide.

(e) Function According to the coating method shown in the embodiment of the present invention, the protrusion side formed on the casting mold (goods) is housed with the motor part (2) reversed in the recess (c) of this casting mold. When the motor part (
2) and the peripheral wall (E) and bottom wall (A) of the casting mold (goods).
24) is connected to the recess (goods) and forms a side channel that is part of this recess and corresponds to the leader line (9), so the casting mold C! By pouring the molten insulating material into the space in (a), the motor part (2) and the leader wire (9) can be covered at the same time. A side part @ is obtained which extends outward from one side and covers the leader line (9). In addition, a part of the case (4) of the motor part (2) that is in contact with the protrusion Cl0) of the casting mold is coated with an annular anti-rust coating in advance to form a coated surface Gυ. Insert the motor part (2) into the recess (C) of the mold (2).
Even if the leader line (9) is slightly displaced from the center of the side track when the ) is stored, a part of the annular painted surface 0]) will always come into contact with the protrusion (to). .

(f) Example The present invention will be described in detail below based on the drawings.

In the figure, (1) is an electric expansion valve used in the refrigeration cycle of refrigerators, air conditioners, and other refrigeration/air conditioning equipment.
and a valve body (3). The motor section (
2) consists of a box-shaped aluminum case (4), a stainless steel cover (5) that covers the bottom surface of the case, and is housed within the case (4) and is driven by receiving a pulse signal. a stepping motor (6) to
A gear mechanism (8) connected to the shaft (force) of this stepping motor, and a plurality of wires extending from the stepping motor (6) to the outside of the case (4) and connected to a signal line from a controller (not shown), On the other hand, the valve body (3) is fixed to the gear mechanism (8) and has a spindle αυ that passes through a stopper α0) attached to the cover (5). , a screw-shaped driver a■ connected to this spindle and screwed into the holder 02, and a telescopic bellows (1
4, is in contact with the lower end of the driver α, and has a needle portion clQ at the lower end.
E9 and a valve seat aη on which the needle portion (15) is seated.
, a bent part 0 seconds formed in the space above the valve seat, and an inlet connected at one end to communicate with this bent part,
It is composed of both outlet pipes (19(a)) and is connected to the motor part (2) by a removable lock nut ■υ.

In the electric expansion valve (1), the stepping motor (3) rotates forward or backward depending on the number of pulse signals sent from the controller, and this rotational movement is caused by the gear mechanism (8) and the spindle α.
υ is converted into a reciprocating linear motion by the transmission mechanism of the driver 03, thereby moving the valve body (17) in the insertion/extraction direction,
The refrigerant flow rate control function from the fully open position where the valve body αη is seated on the valve seat αη to the fully open position where the valve body αη is separated from and above the valve seat (I7), that is, the pressure reduction function and the opening/closing function. It has both.

(22 is a covering material made of a thermal and electrical insulating material such as rubber or resin that covers the motor part (2), and the drawing wire (9)
) is also formed on the side. This covering material (2
By covering the motor part (2) with the material 2, it is possible to improve both the heat insulation and waterproof effects of the motor part (2) used in a low temperature region.

Next, a method of covering the motor section (2) will be explained.

The foundation shown in Figures 4 to 6 is a bottomed cylindrical casting mold with an open upper surface, consisting of a peripheral wall (■) whose inner surface is coated with a mold release agent and a bottom wall (A). A longitudinally long bulge (5) is formed in a part from the bottom wall (26) to form a side passage (c) that becomes a part of the recess. 00) are a suitable number of step-like protrusions that are formed across the inner surface of the peripheral wall and the top surface of the bottom wall (26) and protrude into the recess (28), as shown by the chain lines in FIG. When the motor section (2) is housed in the recess, the motor section is placed so that a space is formed between the outer surface of the case (4) and the inner surfaces of the peripheral wall (2) and the bottom wall (A). I support (2). That is, each protrusion Cl0) serves as a mold contact portion of the motor section (2) and functions to support the motor section (2) and to function as a spacer to form a space. Incidentally, the motor part (2) has a case (as shown in FIG. 5) that faces the protrusion (30).
4) Rust-preventive coating is applied in advance in a band-like manner to an annular surface extending from the outer edge of the upper surface to the upper edge of the circumferential surface, forming a coated surface Oυ.

When storing the motor part (2) in the recess (2) of the casting mold (24), first, the leader wire (9) is tied and attached to the surface of the case (4) with adhesive tape, etc. Motor part (
2) is reversed, that is, the upper surface is the lower surface, and the recess (28
), and the painted surface 0υ of the motor part (2) is placed on each protrusion C30). Casting mold (24) accompanying this placement
A space is formed between the peripheral walls (two and the bottom wall (a) of A molten rubber or resin insulating material is poured into the space, and after a cooling period for the insulating material to harden, the motor part (2) is pulled out from the casting mold 24) to form the motor part (2) as shown in FIG. A covering material (22) is obtained, which is integrally welded to 2) and has a side part (23) that covers the motor part and the leader wire (9). ) is the exposed surface.

According to the method of covering the motor part (2) that causes the motor part (2) to buckle, the protrusion (2) formed between the casting molds will be removed when the motor part (2) is inverted and stored in the recess (28) of the casting mold. Motor part (2
) and the peripheral wall (25) and bottom wall (26) of the casting mold 24). The series forms part of this recess and a side passage (c) corresponding to the leader line (9), so by pouring the molten insulating material into the space inside the casting mold, the motor part ( 2) along with the leader line (9
) can be carried out at the same time, resulting in two covering materials covering the motor part (2) and a side part (c) extending outward from one side of the covering material and covering the lead wire (9). In addition, a part of the case (4) of the motor part (2) that is in contact with the protrusion C30) of the casting mold is coated with an annular anti-rust coating in advance to form a coated surface Gυ. Recess (28) in mold (24)
Even if the leader wire (9) is slightly misaligned from the center of the side track when the motor part (2) is stored in 1, the protrusion 00)
A part of the annular painted surface 0υ will always be in contact with
There is no need to apply anti-rust treatment to the exposed surface of the coating.

(G) Effects of the Invention According to the present invention described above, the effects listed below are produced.

■ The casting mold has protrusions that support the motor when it is housed in the recess, and also form a space between the inner surface of the mold and the motor. By pouring molten insulating material into the casting mold and cooling it, both the motor part and the lead wire can be integrated at the same time. As a result, a covering material with high waterproof, heat-insulating, and electrically insulating effects can be obtained, and the fixing strength of the leader wire can be improved by the side portions that become part of this covering material.

■゛A ring-shaped anti-rust coating is formed on the motor case that comes in contact with the protrusion of the casting mold, so during coating work, the surface that touches the mold,
Not only does this improve the rust prevention effect on the surface that will be exposed after the coating process, but it is also possible to continue the tile coating process even if the furnace part is slightly misaligned when the motor section is stored in the recess. Therefore, the coating work can be performed without worrying about the rust prevention effect after the coating work.

[Brief explanation of drawings]

The drawings all show embodiments of the present invention; FIG. 1 is a longitudinal sectional view of an electric expansion valve with a covering material formed thereon, FIG. 2 is an overall perspective view of the electric expansion valve before the covering material is formed, FIG. 3 is an overall perspective view of the seven-voice part, FIG. 4 is a plan view of the casting mold, FIG. 5 is a cross-sectional view taken along the line AA in FIG. 4, and FIG. 6 is a rear perspective view of the casting mold. (2)...Motor part, (3)...Valve body, (4)...
...Case, (9)...Leader line, (22...Sheathing part, Link...Side part, (2)...Cast hood, (c)
... Peripheral wall, (a) ... Bottom wall, (2□□□...
recess, I29)...side passage, (30)...protrusion,
C31)...Painted surface. Applicant: Sanyo Electric Co., Ltd. (1 other person) Representative: Patent attorney Hisashi Nishino (1 other person) Figure 4 Figure 2 Figure 6 Figure 3

Claims (1)

[Claims] 1. A stepping motor is housed in a case, and in order to cover the motor part of an electric expansion valve, which is composed of a motor part having a lead wire extending outside from the stepping motor and a valve body, a peripheral wall, a bottom wall, A recess defined by both walls, a stepped protrusion spanning both walls, and a side path connected to the recess by bulging one side of the peripheral wall outward. While preparing a casting mold, a ring-shaped anti-rust coating surface is formed in advance at a suitable location on the case in contact with the protrusion, and with a lead wire temporarily attached to the motor section, the motor section is reversed, and The leader wire is housed in a recess corresponding to the side path, and a molten insulating material is poured into the space between the peripheral wall and the bottom wall and the motor section and solidified to cover the motor section and the leader wire. A method of covering a motor part of an electric expansion valve formed by forming a motor part.