JP2015135135A - Electromagnetic proportional valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic proportional valve which changes a shaft to resinous material, and simultaneously forms a breathing groove shape during resin molding.SOLUTION: An electromagnetic portion 12 is equipped with a plunger 17, a yoke 18 fitted with an outer periphery of the plunger 17 and slidably supported, a pin 19 coaxially provided on the plunger 17 and engaged with the plunger 17, a core 20 slidably supporting the pin 19, and a bobbin 22 around which a coil 21 is wound, and fitted and inserted in an outer periphery of the core 20 and the yoke 18. The pin 19 is molded by resinous material, and formed with a pair of breathing grooves 28a on an outer peripheral surface in a vertical direction. Circumferential breathing grooves 31a and 31b adjacent to the breathing grooves 28a and 28b are molded when molding the pin 19.

Description

  The present invention relates to an electromagnetic proportional valve for an automatic transmission of an automobile, and is used to reduce the cost, reduce weight, and improve foreign matter resistance of a shaft that transmits suction force generated by the electromagnetic valve to the valve body of the valve device. The present invention relates to a shaft structure of an electromagnetic proportional valve.

Conventionally, this type of electromagnetic proportional valve includes a bearing 31 that slidably supports a shaft 30 as shown in FIG. 5, for example, and a space α surrounded by the bearing 31 and the plunger 32 is a plunger 32. The volume varies according to the stroke.
Furthermore, the space β on the other side in the axial direction of the bearing 31 is a drain communicating with the outside, and a breathing groove (not shown) is formed on the sliding surface between the shaft (plunger 32) and the bearing 31, and the space α can be changed in volume (for example, refer to Patent Document 1).
As shown in FIG. 6, the bearing 34 includes an insertion hole 35 that penetrates the shaft 33 in the axial direction. The shaft 33 is directly slidably supported on the inner peripheral surface of the insertion hole 35. The space α is a space surrounded by the bearing 34 and the plunger (not shown), and the volume varies according to the displacement of the plunger. A space β on the valve device side indicates a chamber communicating with the outside. And the solenoid valve forms the breathing groove 36 which connects the space (alpha) and the space (beta) between the shaft 33 and the bearing 34, in order to enable the volume fluctuation | variation of the space (alpha) (for example, patent documents). 2).

JP 2004-301295 A Japanese Patent No. 4811386

However, in Patent Documents 1 and 2, when the breathing groove is formed on the inner peripheral surface of the bearing, the inner peripheral surface of the hole must be grooved, and cutting for forming the breathing groove is difficult. Yes, the processing cost was high.
Moreover, although the linear groove | channel along an axial direction is proposed as a breathing groove shape, the eccentric amount of the shaft axis with respect to a bearing axis becomes large.
Therefore, in order to solve these problems, a method of forming the breathing groove in a spiral shape on the outer peripheral surface of the shaft has been proposed. However, it is difficult to cut the spiral shape, and the processing cost increases.
Furthermore, there is a risk that foreign matter may enter the sliding portion of the plunger through the breathing groove, so that sliding failure due to foreign matter biting may occur.
The present invention has been made to solve the above problems, and an object thereof is to provide an electromagnetic proportional valve in which a shaft is changed to a resin material and a breathing groove shape is simultaneously formed at the time of resin molding.

Claim 1 for solving the problem is as follows.
A hydraulic section;
An electromagnetic part integrally attached to the hydraulic part;
In an electromagnetic proportional valve comprising:
The electromagnetic part is
A plunger,
A yoke fitted to the outer periphery of the plunger and slidably supported;
A shaft provided coaxially with the plunger and engaged with the plunger;
A core that slidably supports the shaft pin;
While winding a coil, a bobbin fitted on the outer periphery of the yoke and core;
With
The shaft is formed of a resin material and a pair of breathing grooves provided in the axial direction so as to be directed to both upper and lower end portions from the central portion of the outer peripheral surface of the pin;
A chamber chamber formed adjacent to the breathing groove at a central portion in the axial direction of the shaft;
The chamber chamber is a chamfer formed by chamfering the outer peripheral surface of the shaft perpendicular to the breathing groove,
Circumferential respiration that is formed between the chamfered portion and the inner peripheral surface of the core, and is provided in a circumferential direction between the breathing groove and both axial end surface portions of the chamfered portion. Groove,
Form the
By providing the chamber chamber, the function of functioning as a foreign matter trapping that secures a larger breathing groove volume of the shaft than the amount of breathing in the space due to the stroke of the plunger and prevents foreign matter from entering the plunger side is added. It is characterized by.

By changing the shaft to a resin material and forming the breathing groove shape at the same time as the resin molding, the cost can be reduced.
Furthermore, when a foreign object enters the gap between the shaft and the core sliding part, if the metal slides, the material hardness is high, so the surface will not be deformed or worn, and there is a possibility that the foreign object will be locked while being caught. However, by changing the shaft to a resin material, foreign matter was embedded on the shaft side, the risk of sliding failure was reduced, and foreign matter resistance was improved.

1 is a schematic longitudinal sectional view showing a schematic structure of an electromagnetic proportional valve according to an embodiment of the present invention. It is a plane surface which shows schematic structure of the electromagnetic part of FIG. It is sectional drawing of the III-III line of FIG. It is a cut surface of the III-III line of FIG. It is a longitudinal cross-sectional view which shows the schematic structure of patent document 1. It is a longitudinal cross-sectional view of the shaft support structure of patent document 2.

DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of an electromagnetic proportional valve according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
As shown in FIG. 1, the electromagnetic proportional valve 10 includes a hydraulic part 11 and an electromagnetic part 12. The hydraulic unit 11 includes a sleeve 13, a spool 14 that is slidably inserted into the sleeve 13, and an adjuster 15 that is screwed onto the spool 14. A spring member 16 is mounted between the end of the sleeve 13 and the adjuster 15, and the spool 14 is pressed against the electromagnetic portion 12 by the elastic force of the spring member 16. The hydraulic unit 11 has a general structure and will not be described in detail.

  The electromagnetic unit 12 shown in FIGS. 1 and 2 to 4 includes a plunger 17, a yoke 18 that is fitted on the outer periphery of the plunger 17 and slidably supports the plunger 17, and is provided coaxially with the plunger 17. A pin (shaft) 19 that engages with the pin 17, a core 20 that slidably supports the pin 19, and a bobbin 22 that is wound around the yoke 18 and the core 20 while being wound around the coil 21. . The plunger 17, the yoke 18, the pin 19, the core 20 and the bobbin 22 are crimped on the body 23.

Reference numeral 24 (see FIG. 1) is a spacer provided between the plunger 17 and the pin 19 and has a function of preventing the plunger 17 and the pin 19 from being in close contact with each other. Reference numeral 25 is a connector integrally attached to the bobbin 22, and a terminal A 26 and a terminal B 27 are attached to the connector 25.
As shown in FIGS. 3 and 4, the breathing grooves 28 a and 28 b of the pin 19 fitted into the core 20 are formed of a resin material having a high mechanical strength, for example, PPS. Is formed so that the breathing grooves 28a and 28b directed to both ends above and below the central portion are oriented in the axial direction at two locations, and the discharge or the It functions as a breathing path for absorbing inflowing hydraulic oil.

Further, a chamber chamber 29 is formed in the central portion of the pin 19 in the axial direction adjacent to the breathing grooves 28a and 28b. The chamber 29 is formed between a chamfered portion 30 (see FIG. 4) formed by two chamfering of the outer peripheral surface of the pin 19 perpendicular to the breathing grooves 28 a and 28 b and the inner peripheral surface of the core 20. In addition, breathing grooves (circumferential breathing grooves) 31 a and 31 b are formed in the circumferential direction between the breathing grooves 28 a and 28 b and both end surface portions in the axial direction of the chamfered portion 30.
Therefore, the breathing grooves 28a, 28b, 31a, 31b communicate with each other by the chamber chamber 29 to form a breathing path. As a result, the breathing groove is shaped to turn 90 ° near the central portion of the pin 19 in the axial direction, and the chamber chamber 29 is provided, so that the volume of the space α due to the stroke of the plunger 17 (respiration rate) A function as a foreign matter catching to prevent the foreign matter intrusion to the plunger 17 side was added.

Further, the pin 19 is made of a resin material, and the mold can be used to mold the breathing grooves 28a, 28b, 31a, 31b and the chamber chamber 29, so that the cost can be reduced.
Furthermore, when a foreign object enters the gap between the sliding portion of the pin 19 and the core 20, when the metal slides, the material hardness is high, so the surface does not deform and wear, and it can be locked while the foreign object is caught. However, by changing the pin 19 to a resin material, foreign matter is embedded on the resin pin 19 side, the risk of occurrence of sliding failure is reduced, and foreign matter resistance is improved.

DESCRIPTION OF SYMBOLS 10 Solenoid valve 11 Hydraulic part 12 Electromagnetic part 13 Sleeve 14 Spool 17 Plunger 18 Yoke 19 Pin 20 Core 21 Coil 22 Bobbin 23 Body 24 Spacer 25 Connector 26 Terminal A 27 Terminal B
28a, 28b, 31a, 31b Breathing groove 29 Chamber chamber 30 Chamfer

Claims (1)

A hydraulic section;
An electromagnetic part integrally attached to the hydraulic part;
In an electromagnetic proportional valve comprising:
The electromagnetic part is
A plunger,
A yoke fitted to the outer periphery of the plunger and slidably supported;
A pin coaxially provided on the plunger and engaged with the plunger;
A core that slidably supports the pin;
While winding a coil, a bobbin fitted on the outer periphery of the yoke and the core 20,
With
The pin is formed of a resin material, and a pair of breathing grooves provided to be directed to both upper and lower end portions from the central portion of the outer peripheral surface of the pin;
In the central portion of the pin in the axial direction, a chamber chamber formed adjacent to the breathing groove,
The chamber chamber is a chamfer formed by chamfering the outer peripheral surface of the pin perpendicular to the breathing groove,
Circumferential respiration that is formed between the chamfered portion and the inner peripheral surface of the core, and is provided in a circumferential direction between the breathing groove and both axial end surface portions of the chamfered portion. Groove,
Form the
By providing the chamber chamber, the pin has a larger breathing groove volume than the amount of breathing in the space α due to the stroke of the plunger), and a function as a foreign matter trapping that prevents foreign matter from entering the plunger side is added. Proportional solenoid valve.

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