JPS62110085A - Solenoid-operated proportional control valve - Google Patents

Abstract

PURPOSE:To prevent the occurrence of contamination on the spool sliding part and the valve seat in a pilot part by projecting the jet port of a nozzle toward the valve seat of a pilot valve. CONSTITUTION:The length of breadth of the land 3a at the end part receiving a pilot oil pressure of a spool 3 in a main part 1 is made shorter than the full stroke 7 of the spool 3 Further, in the cylindrical part 24 at the end part of the spool 3 receiving a pilot pressure, a nozzle 27 which is projected in the cylindrical part 21a of a pilot part 5 is supported so as to be fitted. The pressure oil flowed into a ring-shaped groove 14 via an inlet 16, after passing through an orifice 40, is jetted out into the cylindrical part 21a of the housing 9 of the pilot part 5 through a nozzle 27.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic proportional 11 valve used for controlling the speed of a hydraulic actuator.

[Prior Art] As shown in FIG. 2, a conventional electromagnetic proportional control valve is composed of a main part 1, a pilot part 5, and a solenoid part 25. The main part 1 has a valve chamber in the housing 2, which is composed of a large diameter cylindrical section 22 and a small diameter cylindrical section 22a, and the end of this valve chamber is closed by fitting an end wall 44 and fixing it with a retaining ring 43. be done.

An annular groove 1 is formed at the boundary between the large diameter cylindrical portion 22 and the small diameter cylindrical portion 22a.
5 is provided and communicated via an outlet 17 to a hydraulically actuated device M. Notches 15a are provided on both sides of this annular groove 15 to control the flow of pressure oil.

An annular groove 1 is formed in the large diameter cylindrical portion 22 around the annular shape 11115.
4 is provided and communicates with the discharge port of the hydraulic pump P via an inlet 16. Further, an annular groove 4 is provided in the small diameter cylindrical portion 22H.
8 is provided and communicates with the oil tank 20 via an outlet 49. This annular groove 48 is also provided with a notch 48a.

A spool 3 having a large diameter portion that fits into the large diameter cylindrical portion 22 and a small diameter portion that fits into the small diameter cylindrical portion 22a is fitted into the valve chamber.

This spool 3 has a wide annular groove 60 that is always continuous with the annular groove 14, an annular groove 41 that is continuous with the annular groove 15, and an annular groove 4.
8 and a wide annular groove 42. A cylindrical portion 46 that supports one end of the spring 45 is provided on the small diameter end side of the spool 3. The other end of the spring 45 is abutted against the end wall 44. The force of this spring 45 normally presses the spool 3 against an end wall 23 of the housing 9, which will be described later. The cylindrical portion 46 is provided with a radial orifice 53, which allows the end chamber 19 and the annular groove 48 to communicate with each other. An axial cylindrical portion 28 is provided on the large diameter end side of the spool 3, and the inner diameter of this open end is enlarged. This axial cylindrical portion 28 forms a radial orifice 4o.
It communicates with the annular groove 14 via.

The pilot part 5 has a seal member 6 in the large diameter cylindrical part 22 of the valve chamber.
The housing 9 is fitted through the housing 2. This housing 9 is positioned by a conical portion, and a passage 51 consisting of a radial groove is provided at this end. The housing 9 is provided with a valve chamber 1o consisting of a small-diameter cylindrical portion 21a and a large-diameter cylindrical portion, and a valve seat 21 is formed in a stepped portion of both. The pilot valve 8 is fitted into the valve chamber 10, and a spring 38 is interposed between the end flange and the step portion described above. The force of this spring 38 causes the pilot valve 8 to abut against an iron core 56, which will be described later. In this way, the main part 1 and the pilot part 5 are formed in the housing 2, and the solenoid part 25 is coupled to the end of the housing 2 via the cup-shaped cap 32.

A guide cylinder 39 into which the plunger 34 is fitted is disposed inside the cap 32, and a spring 35 is interposed between the stopper 33 fitted inside the guide cylinder 39 and the plunger 34. The plunger 34 is provided with a through hole including an orifice 36, which communicates with a cylindrical portion 57 provided in the iron core 56. One end of the spring 7 accommodated in this cylindrical portion 57 abuts against the plunger 34, and the other end abuts against the pilot valve 8 described above.

The end flange of the iron core 56 is fitted into the cylindrical portion of the housing 2, while the end of the guide 1139 is fitted externally. Further, an iron core 37 having a flange 37a is fitted onto the guide tube 39, and a winding frame around which the electromagnetic coil 61 is wound is fitted between the iron core 37 and the iron core 56. A pad 26 for positioning the iron core 37 is housed deep inside the cap 32. Also, from the electromagnetic coil 61, a terminal conductor or a connector 31
connected to the pin. This connector 31 has a cap 32
protrudes from the peripheral wall of the

As described above, in the so-called pressure balanced electromagnetic proportional control valve, which applies a pilot pressure to the spool 3 of the main part 1 according to the stroke of the pilot valve 8 by the plunger 34 by adjusting the current of the solenoid part 25,
Compared to a 0N-OFF type electromagnetic proportional control valve of the same size, the operating force of the solenoid part 25 is smaller (control force is weaker), and because it performs minute movements while maintaining pressure balance, it is possible to Contamination often occurs, such as foreign matter entering or getting caught in the 1N moving part of the spool that separates the high pressure part of section 1 from the low pressure parts of pyrowers 1 to 8, and the valve seats of the valves. The drawback is that smooth operation is likely to be impaired.

In particular, as shown in Figure 1, despite its small size, it is relatively weak because it controls the flow rate of high-pressure multiple pressure oil. ! In devices that control pilot oil pressure using magnetic force, the high pressure section and low pressure section are next to each other, and there is a risk that pressure oil may leak from the high pressure section to the low pressure section through the gap, and foreign matter may accumulate in the gap. be.

Further, in the conventional electromagnetic proportional control valve, the outlet of the pilot pressure oil is provided inside the end of the spool 3, so foreign matter tends to accumulate between the end of the spool 3 and the valve seat. That is, as shown in FIG. 2, in the electromagnetic proportional control valve, the axial dimension (width S of the land 3a) of the end adjacent to the pilot part 5 of the spool 3 that fits into the large diameter cylindrical part 22 of the main part 1 is Since the spool 3 is long, if a foreign object gets caught in this part, the spool 3 will not move smoothly. Since the land 3a separates the high-pressure part connected to the discharge port of the hydraulic pump from the low-pressure part or pilot air, which is depressurized through the orifice 40, leakage of pressure oil from the high-pressure part to the low-pressure part is always prevented. This is likely to occur, and together with this pressure oil, foreign matter may be trapped between the land 3a and the large diameter cylindrical portion 22 of the valve chamber.
It is easy to get in between.

Furthermore, in the conventional electromagnetic proportional control valve, the outlet (cylindrical part 28) of the passage connecting from the high pressure part to the low pressure part or pilot chamber via the orifice 4o has a large diameter at the end of the spool 3, so that the pressure oil The flow speed of the pressure oil is slow, and foreign matter mixed in the pressure oil tends to stay near the valve seat 21, which affects the pilot oil pressure of the spool 3.
1 and the pilot valve 8, and the smooth and stable operation of the spool 3 is hindered.

[Problems to be Solved by the Invention] Therefore, in view of the above-mentioned problems, the purpose of the present invention is to solve the problems of the spool sliding part of the main part and the pilot part by making only temporary changes to the conventional electromagnetic proportional control valve. An object of the present invention is to provide an electromagnetic proportional control valve that can prevent contamination from occurring on a valve seat.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the present invention is such that a nozzle for feeding pressure oil to the pilot section is provided inside the spool of the main section, and the ejection port of the nozzle is connected to the pilot section. It protrudes toward the valve seat of the valve and allows foreign matter between the pilot valve and the valve seat to flow out due to the flow of pilot pressure oil.

[Function] By making the amount of protrusion of the nozzle 27 from the end face of the spool 3 longer than the full stroke t of the spool 3, the tip of the nozzle 27 remains inside the valve seat 21 even when the spool 3 makes a full stroke. The flow of the pilot pressure oil is quickly ejected toward the valve chamber 1o without causing any foreign matter to remain between the end face of the spool 3 and the valve seat 21. This reduces the possibility of foreign matter staying in the vicinity of the end of the spool 3, ensuring smooth operation of the spool 3.

[Examples of the Invention] The present invention will be described based on Examples. As shown in FIG. 1, according to the present invention, the length or width of the land 3a at the end of the main portion 1 that receives the pilot oil pressure of the spool 3 is made shorter than the full stroke t of the spool 3. Furthermore, the cylindrical part 24 of the pilot part 5 is attached to the cylindrical part 24 at the end of the spool 3 that receives the pylon I and the hydraulic pressure.
1a/\Protruding nozzle 27 is fitted and supported. The other configurations are substantially the same as those of the conventional example shown in FIG. 2, so similar constituent members are given common reference numerals and explanations will be omitted.

By configuring the present invention as described above, the pressure oil flowing into the annular groove 14 from the discharge port from the hydraulic pump P via the inlet 16 passes through the orifice 40 and flows into the cylindrical portion of the spool 3.
4, and is further ejected from the nozzle 27 into the cylindrical portion 21a of the housing 9 of the part 5 of the pyrower 1. therefore,
Even if foreign matter is mixed in the pressure oil, the valve seat 2 will be removed from the nozzle 27.
1, the foreign matter enters the inside of the valve seedling 10 without remaining in the valve seat 21, and is returned to the oil tank 20 via the passage 51F3 and the outlet 17.

Also, since the width S of the land 3a at the end of the spool 3 is smaller than the full stroke i and the loaf t of the spool 3, the large diameter cylindrical portion 22 and the land 3a are
When the spool 3 moves downward in the figure, the foreign matter does not remain in the fitting part of the nozzle 2 and flows into the gap between the end surface of the pool 3 and the end wall 23 of the housing 2.
The pressure oil ejected from 7 is discharged to the oil tank 20 along the flow as in the case described above.

According to the present invention, by making use of the control pattern of an automobile clutch mechanism and making the width of the land 3a of the spool 3 shorter than the full stroke, when the spool 3 makes a full stroke at the initial input, the annular groove 1 Even if foreign matter present in the land 3a may enter the sliding portion of the land 3a, the foreign matter will flow out over the sliding portion of the land 3a, and the foreign matter will be prevented from staying in the land 3a.

As an electromagnetic proportional control valve for a hydraulic actuator for operating a clutch mechanism during automatic gear shifting of an automobile, the connection pattern of the clutch mechanism is as shown in FIG. ■The spool 3 temporarily makes a full stroke at the beginning of the connection operation of the structure, so it is suitable for use with this hydraulic actuator! Ill oil also serves as a lubricating oil for float shifting, and even in situations where foreign matter is easily mixed, the above-mentioned configuration prevents foreign matter from accumulating inside the electromagnetic proportional control valve, resulting in a highly reliable spool. 3 actions are obtained,
This ensures smooth connection operation of the clutch mechanism.

[Effects of the Invention] According to the present invention, as described above, the pressure oil that flows from the discharge port of the hydraulic pump P through the inlet 16 into the annular groove 14 enters the cylindrical portion 24 of the spool 3 through the orifice 40, and further Since the oil is ejected from the nozzle 27 to the cylindrical part 21a of the pilot part 5, even if foreign matter is mixed in the pressure oil, the nozzle 27
Since the foreign matter is strongly ejected toward the valve seat 21, it enters the inside of the valve v10 without remaining in the valve seat 21, and is discharged into the oil tank 20 via the passage 51 and the outlet 12. . Furthermore, since the width S of the land 3a at the end of the spool 3 is smaller than the full stroke t of the spool 3, foreign matter remains at the 144 joint between the large diameter cylindrical portion 22 and the land 3a due to the full stroke of the spool 3. Instead, it flows out between the end face of the spool 3 and the end wall 23 of the housing 2, which occurs when the spool 3 makes a full stroke.
Eventually, the pressure oil is ejected from the nozzle 27 and discharged into the oil tank 20 along the flow.

[Brief explanation of drawings]

FIG. 1 is a front sectional view of the 11 magnetic proportional control valve according to the present invention,
FIG. 2 is a front sectional view of a conventional electromagnetic proportional control valve, and FIG. 3 is a miniature diagram showing an example of a control current applied to a solenoid portion of the electromagnetic proportional control valve.

Claims (2)

[Claims] (1) A nozzle for sending pressure oil to the pilot part is provided inside the spool of the main part, and the jet port of the nozzle protrudes toward the valve seat of the pilot valve, and the flow of the pilot pressure oil causes the pilot valve and the valve seat to An electromagnetic proportional control valve characterized by allowing foreign matter to flow out between the valves. (2) The width of the land at the pilot valve side end is made shorter than the full stroke length of the spool, and the full stroke of the spool prevents foreign matter from accumulating between the land and the valve chamber. ) electromagnetic proportional control valve.