JPH01182680A - Electric control valve - Google Patents

Abstract

PURPOSE:To lighten a burden being imposed on a thread part and thereby reduce the wear and the occurrence of vibrational noise by installing a guide part in a refrigerant controlling electric control valve for a refrigeration system or the like together with the thread part. CONSTITUTION:A closed type case 23 is fixed on a valve body 20, and there is provided with a fixed supporting member 24 as hung down toward the valve body 20 from an upper end of the closed type case 23. A cylindrical guide part 24a and an external thread part 24b are installed in this fixed supporting member 24 continuously in the axial direction. In addition, an internal thread part 28a being screwed in the external thread part 24b and a sliding pipe part 28b being engaged with the guide part 24a both are installed in an engaging pipe 28 to be clamped to the inside of a rotor 25.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electric control valve used for controlling the flow rate of refrigerant, such as an electric expansion valve in a refrigeration system.

Figure 3 shows a conventional example (Japanese Patent Application Laid-open No. 196477/1983)
The electric control valve consists of a valve part (2) and a part M of a stepping motor.In the valve part (2), a valve seat 2a is provided on a partition wall 2 between a part of the valve body 1 and a secondary rotor 1b. A needle valve 3 moves into and out of contact with the seat 2a, and the needle valve 3 is supported slidably in the axial direction within a male screw tube 4 screwed onto the valve body 1 on the side of the secondary roller lb. has been done.

A lower cover 5 is provided on the upper part of the valve body 1 with the male screw tube 4 in the center, and a sealed wall case 6 of the stepping motor part M is fixed onto the lower cover 5. Case 6
A stator 8 having a built-in coil 7 is provided on the outer periphery of the stator 8 . A rotor 9 is rotatably supported within the case 6 by the male threaded tube 4. The rotor 9 is the support tube 1
A cylindrical permanent magnet 11 is fitted to the outer circumferential portion of the magnet 0, and then the upper edge 10a is expanded over the permanent magnet 11 to integrate the two. A female screw tube 12 which is fixedly screwed onto the male screw tube 4 is provided so as to be rotatable and movable in the axial direction.

A connecting plate 10b is formed in the axially intermediate portion of the support cylinder 10, and after the small diameter portion 3a of the needle valve 3 is inserted into the hole 10c of the connecting plate 10b, it is fixed with a stopper 13 such as an E-ring. A compression coil spring 14 is attached to the small diameter portion 3a of the needle valve 3.
is wrapped between the step portion 3b and the connecting plate 10b.

In this structure, the rotor 9 is rotatably supported by screwing a female threaded tube 12 provided on its inner circumference to a male threaded tube 4 fixed to the valve body 1. Since it is supported only by the threaded part, there is a drawback that the threaded part is easily worn out and vibration noise is easily produced.On the other hand, a structure with bearings provided at both ends requires high accuracy in the centering manufacturing technology.

- The present invention has been made with attention to the above-mentioned points, and by providing a guide section together with the threaded section, the load on the threaded section is reduced, thereby reducing its wear and vibration. This is designed to reduce the amount of sound generated.

In order to achieve the above-mentioned objective of reducing the amount of the needle valve, the needle valve is brought into contact with and separated from the valve seat of the valve body by the rotation of the rotor, and the needle valve is brought into contact with and separated from the valve seat of the valve body by rotation of the rotor, and the needle valve is moved in the axial direction from the fixed support member. A male screw portion and a cylindrical guide portion are provided continuously to the rotor, and a female screw portion that is screwed into the male screw portion and a sliding tube portion that is engaged with the guide portion are provided on a storage tube that is fixed inside the rotor. We adopted a configuration that provides

1 boat group In FIG. 1, the electric control valve consists of a valve part V and a part M of a stepping motor. is provided, and the needle valve 22 moves toward and away from the valve seat 21a.

A closed case 23 of the stepping motor part M is fixed on the valve body 20, and a fixed support member 24 is provided hanging from the upper end of the closed case 23 in the direction of the valve body 20. The fixed support member 24 has a cylindrical guide portion 24a and a male screw portion 24b connected in the axial direction.

25 is a rotor, and the rotor 25 is fitted with a cylindrical permanent magnet 27 on the outer periphery of the support tube 26, and then the upper and lower edges 26a are expanded onto the permanent magnet 27 to integrate both. The female screw portion 28a of the storage tube 28, which is crimped and is fitted and fixed to the intermediate connecting portion 26b of the support tube 26, is connected to the male screw portion 24.
b, and the sliding tube portion 28b is engaged with the guide portion 24a.

A connecting pipe 29 is further fixed to the connecting part 26b of the support tube 26, and the small diameter part 22a of the needle valve 22 penetrates through the hole 29b of the bottom wall 29a of the connecting pipe 29 to form the stopper 22b.
is configured to engage with the bottom wall 29a, and the bottom wall 29
A compression coil spring 30 is provided between the needle valve 22a and the stepped portion 22c of the needle valve 22, and the coil spring 30 always biases the needle valve 22 in the closing direction.

A stator 32 containing a coil 31 is provided on the outer periphery of the closed case 23 . Reference numeral 33 indicates an engagement rod provided on the rotor 25, and reference numeral 34 indicates a stopper, both of which engage during one final rotation of the rotor 25 when the valve is closed.

In the above configuration, when the coil 31 of the stator 32 is energized, the rotor 25 rotates and moves upward and downward due to the screw engagement between the female screw portion 28a and the male screw portion 24b, and the sliding tube portion 28b is used as a cylindrical guide. 24a. coil 3
1, the rotor 25 attempts to move unevenly in the axial and radial directions, but the sliding tube portion 28b
Due to the engagement between the guide portion 24a and the screw portion, the above-mentioned movement is received in a distributed manner by the screw portion, which reduces wear on the screw portion and also reduces rattling noise of the screw portion during operation.

In the embodiment of FIG. 2, a cylindrical fixed support member 24'
is provided upright on the upper part of the valve body 20, and has a cylindrical guide part 24a' and a male screw part 24b' connected to each other, and is fitted and fixed inside the support cylinder 26' of the rotor 25. tube 2
The female screw portion 28a' of 8' is screwed into the male screw portion 24b', and the sliding tube portion 28b' is engaged with the guide portion 24a'.

The needle valve 22' passes through the fixed support member 24', and its small diameter portion 22a' is attached to the upper wall 29 of the connecting pipe 29', which is fixed in the support cylinder 26' at the upper part of the engagement pipe 28'.
The hole 29b' of the upper wall 29b' is configured to protrude above the hole 29b' of the upper wall 29b' and engage with the upper wall 29a'.
A compression coil spring 30 is provided between a' and the stepped portion 22C' of the needle valve 22'.

In FIG. 2, the same reference numerals are given to the same structural parts as in FIG. 1.

Main Unit ■Fourth As described above, the present invention is such that the needle valve that approaches and separates from the valve seat of the valve body is brought into contact with and separated from the valve seat by the rotation of the rotor, and the male threaded portion is continuously connected to the fixed support member in the axial direction. and a cylindrical guide part, and a storage tube fixed inside the rotor is provided with a female screw part that screws into the female thread part and a sliding pipe part that engages with the guide part. Therefore, it has the advantage of reducing wear on the threaded portion of the bearing and, in particular, reducing pitching vibration of the rotor.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the present invention, FIG. 2 is a sectional view of another embodiment of the same, and FIG. 3 is a sectional view of a conventional example. DESCRIPTION OF SYMBOLS 20... Valve body, 21a... Valve seat, 22... Needle valve, 24... Fixed support member, 24a... Cylindrical guide part, 24b... Male screw part, 25...・Rotor,
28...Storage tube, 28a...Female screw portion, 28b...
・Sliding pipe section.

Claims (1)

[Claims] The needle valve, which approaches and separates from the valve seat of the valve body, is brought into contact with and separated from the valve seat by the rotation of the rotor, and the fixed support member is provided with a male screw part and a cylindrical guide part continuous in the axial direction. An electric control valve characterized in that a fixed engagement tube is provided with a female screw portion that screws into the male screw portion and a sliding tube portion that engages with the guide portion.