JP2004019927A - Solenoid valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the switching performance of a solenoid valve by reducing noise on impact and preventing a suction force from lowering. <P>SOLUTION: This solenoid valve 1 comprises: a fixed steel core 2, a solenoid coil 3 installed around the fixed steel core; a movable steel core 4 moved by the sucking force of the fixed steel core and the solenoid coil; and a valve part 5 formed so as to control the flow of fluid by the movable steel core. A plate spring member 31 formed of a magnetic body is installed between the fixed steel core and the movable steel core, and the plate spring member is formed to have a spring force to separate the fixed steel core from the movable steel core in the thickness direction of the plate spring member. Also, the plate spring member is formed in a generally disk shape having a center part 32 and an outer peripheral part 33, and a step 34 is provided between the center part and the outer peripheral part. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a reduction in operation noise of a solenoid valve used for an industrial machine, a transportation machine, and the like, and an improvement in switching performance.
[0002]
[Prior art]
The solenoid valve generates a collision sound in which the fixed iron core and the movable iron core collide in addition to the fluid noise. As the noise of automobiles has been reduced, it is necessary to reduce such collision noise in solenoid valves for automatic transmissions of automobiles such as AT and CVT. The collision sound is generated as the movable iron core moves, and the collision noise is generated when the movable iron core comes into contact with the valve seat or separates from the valve seat and comes into contact with the fixed iron core. Therefore, in Japanese Utility Model Laid-Open No. 3-130976, Japanese Utility Model Laid-Open No. 5-96656, and Japanese Patent Application Laid-Open No. Hei 7-224962, an elastic member such as rubber is used for a movable iron core side seat portion that contacts a valve seat. The member is extended to the fixed iron core side so that an elastic member is interposed on the contact surface with the fixed iron core.
[0003]
On the other hand, between the fixed iron core and the movable iron core of the solenoid valve, when the solenoid is energized and the movable iron core is attracted to the fixed iron core, the fixed iron core and the movable iron core are prevented from adhering to each other, and the solenoid is A non-magnetic washer-shaped spacer is provided to make it easy to separate the fixed iron core and the movable iron core when not energized. Therefore, in Japanese Patent Application Laid-Open No. H8-210547, the spacer between the fixed iron core and the movable iron core is made of a non-magnetic leaf spring, thereby reducing the impact force and noise by the elastic force of the leaf spring and reducing the fixed iron core. A single member serves to prevent the close contact with the movable iron core.
[0004]
[Problems to be solved by the invention]
However, compared to a solenoid valve having a structure without a spacer, a valve with a spacer has a greater distance between the fixed iron core and the movable iron core by an amount corresponding to the thickness, and the suction force when energizing the solenoid is reduced. Further, in the above-mentioned Japanese Patent Application Laid-Open No. H8-210547, although the noise is reduced by the elastic force of the leaf spring, on the other hand, the resistance due to the elastic force of the leaf spring is added in addition to the thickness of the spacer. There is a problem that a decrease in the density occurs.
[0005]
SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to reduce noise at the time of collision, prevent a decrease in suction force, and improve the switching performance of a solenoid valve.
[0006]
[Means for Solving the Problems]
In the present invention, a fixed iron core, a solenoid coil provided around the fixed iron core, a movable iron core movable by an attraction force of the fixed iron core and the solenoid coil, and a flow of fluid by the movable iron core And a valve unit configured to control the solenoid valve, wherein a leaf spring member made of a magnetic material is provided between the fixed iron core and the movable iron core, and the leaf spring member is connected to the fixed iron core. The above object has been achieved by providing a solenoid valve having a spring force that separates a movable iron core from a movable core in a thickness direction of a leaf spring member.
[0007]
That is, since the so-called spacer is made of a magnetic leaf spring member instead of a non-magnetic material, the distance between the fixed iron core and the spacer (leaf spring member) is made of a non-magnetic material. It is smaller than using spacers. Therefore, the suction force at the time of energizing the solenoid is increased, and the operability is improved. On the other hand, since the leaf spring member as a spacer has elastic force, the impact at the time of collision between the fixed iron core and the movable iron core is reduced, and the collision noise is also reduced. Further, when the solenoid is energized and de-energized, the spring force of the leaf spring member acts to separate the movable iron core from the fixed iron core in the thickness direction of the leaf spring member. The movable iron core is easily separated, and the returnability of the solenoid valve when power is not supplied is improved.
[0008]
In the present invention, it can be easily obtained by making the non-magnetic elastic member of JP-A-8-210547 a magnetic material. Therefore, the configuration shown in FIG. 2 of FIG. 2 may be similar to that of FIG. 2, FIG. 5 and FIG. 5 and 6 of the publication have a simple shape with a single flat plate, but a relief process of a curved surface or a conical surface for causing a leaf spring to act as a spring is required on the fixed iron core side. . Therefore, in the present invention described in claim 2, the leaf spring member is substantially disk-shaped having a central portion and an outer peripheral portion, and a step is provided between the central portion and the outer peripheral portion. According to this, the fixed iron core and the movable iron core may be the same as the conventional one, and the solenoid valve of the present invention can be easily provided by replacing the conventional spacer with the conventional spacer.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a solenoid valve showing an embodiment of the present invention. The left side from the center line shows a state when the solenoid coil is energized, and the right side shows a state when the solenoid coil is not energized. FIG. 3 is a partially enlarged cross-sectional view showing the leaf spring member of the present invention surrounded by an ellipse A. The left side of the center line shows a state when the solenoid coil is energized, and the right side shows a state when the solenoid coil is not energized. As shown in FIG. 1, the fixed iron core 2 is provided at a cylindrical portion 7 having a space portion 6 having a concave cross section, a flange portion 9 provided at an opening end 8 of the space portion, and a bottom portion 10 of the space portion. A through hole 11 is provided. The solenoid coil 3 is fitted so as to be in contact with the outer side 7a of the cylindrical portion 7 of the fixed iron core 2 and the outer peripheral surface 9a of the cylindrical portion of the flange portion 9. The solenoid coil 3 has a winding 3b wound around a bobbin 3a made of plastic. The upper end 3c of the bobbin 3a is disposed so as to face the flange 9, and the inner diameter 3d of the bobbin 3a is inserted into the outer peripheral surface 7a of the cylindrical portion. A cylindrical iron yoke 16 having an L-shaped cross section is fixed to the lower end of the bobbin 3a. The terminal portion 17 protrudes from below the bobbin 3a in the radial direction, and electric power is supplied from the outside. A movable iron core 4 is provided movably along the lower end 2a of the fixed iron core 2 and the inner diameter 3e of the bobbin 3a.
[0010]
In particular, in the present invention, as shown in FIG. 2, a leaf spring member (spacer) 31 made of a magnetic material is provided between the fixed iron core 2 and the movable iron core 4. The leaf spring member 31 has a substantially disk shape having a central portion 32 and an outer peripheral portion 33, and a step 34 is provided between the central portion and the outer peripheral portion. The central portion 32 is in contact with the lower end 2 a of the fixed iron core 2, and the center side 35 of the outer peripheral portion 33 is in contact with a spring 19 described later, and is sandwiched between the spring 19 and the fixed iron core 2. A drain hole 36 is formed in the center of the central portion 32.
[0011]
The movable iron core 4 has a hollow cylindrical shape having a concave hole 4a, and a pin 4b is fixed to the bottom. A spring 19 is provided in the concave hole 4a, and the upper part of the spring can be brought into contact with the fixed iron core lower end 2a via a leaf spring member 31. The spring force of the spring 19 causes the movable iron core 4 and the fixed iron core 2 to be in contact with each other. Are separated from each other. The valve section 5 is provided below the movable iron core 4 and the yoke 16. The valve portion 5 has a flange 5a at an upper portion, and is caulked and fixed so that the flange 5a of the valve portion, the yoke 16, the solenoid coil 3, and the flange portion 9 of the fixed iron core 2 are sandwiched between both ends 20a and 20b of the cover 20. Have been. FIG. 1 shows a normally closed valve having two positions in three directions. The valve portion 5 has a pressure port side valve seat 22 opened at the lower end and a pressure port side valve seat 22 and a ball 23 seated on and off the pressure port side valve seat. Is provided. Above the ball 23, a tank port side valve seat 24 that opens downward is provided, and the ball is arranged so as to be detachable and seatable. A load port 25 is provided in communication between the pressure port valve seat 22 and the tank port side valve seat 24, and is connected to a load (not shown). The tank port side valve seat 24 is connected to the pin through hole 24a, communicates with the tank port 26 via the tank hole 24b, and is discharged outside the solenoid valve.
[0012]
The tip of the pin 4b of the movable iron core 4 can be brought into contact with the ball 23 by the spring force of the spring 19, so that when the solenoid 3b is energized, the pin 4b is attracted to the fixed iron core 2 and does not contact the ball. Is done. As shown on the right side of FIG. 1, in the case of the solenoid non-conductive electromagnetic, the ball 23 is pushed by the pin 4 b by the spring force of the spring 19 and seats on the pressure port side valve seat 22, and the pressure port 21 and the load port 25 It shuts off and connects the load port 25 and the tank port 26. On the other hand, as shown on the left side of FIG. 1, when the solenoid 3b is energized and the pin 4b is separated from the ball 23, the ball is pushed by the pressure of the pressure port 21 and sits on the tank port side valve seat 24, and the pressure is reduced. The port 21 and the load port 25 are communicated, and the load port 25 and the tank port 26 are cut off. This provides a normally closed valve in two directions in three directions that switches the flow path by turning on and off the solenoid 3b. The opening side of the fixed iron core 2 is open to the outside of the solenoid valve, and the internal leak of the solenoid valve 1 is drained through the drain hole 35 of the leaf spring member 31, the through hole 11 of the fixed iron core, and the like. Discharged outside the solenoid valve.
[0013]
In the present invention, the movable iron core 4 collides with the fixed iron core 2 when the solenoid 3b is energized, but the impact is reduced by the elastic force of the leaf spring member 31 while moving from the right side view to the left side view of FIG. You. On the other hand, in the suction state, since the leaf spring member is a magnetic material, the fixed iron core and the leaf spring member are integrated, and the movable iron core is sucked with a strong suction force. More specifically, FIG. 3 is an explanatory diagram showing the relationship 40 between the stroke from the fixed iron core to the movable iron core and the solenoid attraction force. When the solenoid is not energized, the movable iron core and the fixed iron core in the case of a non-magnetic spacer are used. Is the sum of the thickness 42 of the non-magnetic spacer and the stroke 43 of the movable iron core. On the other hand, in the present invention, since the fixed iron core and the magnetic material spacer are magnetically integrated, the air gap between the movable iron core and the fixed iron core is only the movable iron core stroke 44, and the air gap is equal to the thickness of the spacer. Becomes shorter. Therefore, the allowable spring force 44 of the spring 19 with respect to the movable iron core stroke is larger than the allowable spring force 46 of the conventional spring 19. Conversely, the solenoid attraction force may be small for the same spring force. Therefore, the operating voltage when energizing the solenoid is 7 to 7.5 V when a conventional non-magnetic washer-shaped spacer (without spring force) is used, whereas the leaf spring member of the magnetic material of the present invention is used. In this case, the voltage dropped to 5.5 to 6 V, and the suction force was improved by about 20%.
[0014]
Further, when the movable iron core is returned from the energized state to the non-energized state, since the leaf spring member of the present invention is made of a magnetic material, the fixed iron core and the movable iron core are easily brought into close contact with each other, and it is difficult to return (cancel). However, since the leaf spring member of the present invention acts to separate the movable iron core from the fixed iron core by a spring (elastic) force in the thickness direction (axial direction), the movable iron core is magnetically released from the fixed iron core. And the performance of returning to the non-energized position is improved. More specifically, FIG. 4 is an explanatory diagram showing the relationship between the stroke 51 from the fixed iron core to the movable iron core, the thickness 52 of the spacer, and the sum of the spring forces of the spacer and the spring 19. In contrast to the spring force 54 of the nineteenth embodiment, the spring force 55 of the present invention exerts a large spring force in the thickness direction of the leaf spring member, particularly in a stroke near suction, and the return force 56 of the movable iron core is large. Become. Conversely, the holding current of the movable iron core returns to a high value. Therefore, the return current from the solenoid energized state to the non-energized state is 90 to 100 mA when a conventional non-magnetic washer-shaped spacer (without a spring force) is used, whereas the magnetic material plate of the present invention has a return current of 90 to 100 mA. In the spring member, the return current was about 20% higher at 110 to 120 mA, and the spring member returned more quickly when the current was interrupted.
[0015]
In the above-described embodiment, the thickness of the leaf spring member is the same as that of the conventional spacer, that is, 0.15 mm, and the step is 0.15 mm. Further, in the embodiment, the normally closed valve in two positions in three directions has been described. However, it is needless to say that the present invention can be applied to a normally open valve and other solenoid valves. Further, the shape of the leaf spring member may be the same as that of the conventional non-magnetic elastic member disclosed in Japanese Patent Application Laid-Open No. H8-210547, and it goes without saying that various shapes are possible.
[0016]
【The invention's effect】
According to the present invention, a leaf spring member is provided between the fixed iron core and the movable iron core of the solenoid valve, and the leaf spring member has a spring force that separates the fixed iron core and the movable iron core in the thickness direction of the leaf spring member. In the solenoid valve, by changing the material of the leaf spring member from a non-magnetic material to a magnetic material, it is possible not only to reduce the collision noise, but also to obtain a high suction force and a return force that were not expected in the past. became. Therefore, the switching performance of the solenoid valve is improved, and if the rating is the same, the output of the solenoid is reduced to save energy.If the solenoid output is the same, the rated flow rate can be increased, or it is resistant to dust and the environment. Was. Further, since the spacer has elasticity, not only noise is reduced but also durability of the leaf spring member is improved.
[0017]
Further, the leaf spring member is formed in a substantially disk shape having a central portion and an outer peripheral portion, and has a simple structure in which a step is provided between the central portion and the outer peripheral portion. Processing and assembly are easy, and the material is inexpensive. Further, since the solenoid valve of the present invention can be easily provided by replacing the conventional spacer, the versatility is enhanced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a solenoid valve according to an embodiment of the present invention, in which a left side from a center line shows a state when a solenoid coil is energized, and a right side shows a state when a solenoid coil is not energized.
FIG. 2 is a partially enlarged cross-sectional view showing a leaf spring member of the present invention encircled in FIG. 1, in which a left side from a center line shows a state when a solenoid coil is energized, and a right side shows a state when a solenoid coil is not energized.
FIG. 3 is an explanatory diagram showing a relationship between a stroke from a fixed iron core to a movable iron core and a solenoid attraction force.
FIG. 4 is an explanatory diagram showing a relationship between a stroke from a fixed iron core to a movable iron core and a sum of spring forces of a spacer and a spring 19;
[Explanation of symbols]
Reference Signs List 1 solenoid valve 2 fixed iron core 3 solenoid coil 4 movable iron core 5 valve portion 31 leaf spring member (spacer)
32 Central part 33 Outer part 34 Step

Claims (2)

A fixed iron core, a solenoid coil provided around the fixed iron core, a movable iron core movable by the attraction force of the fixed iron core and the solenoid coil, and a flow of fluid is controlled by the movable iron core. A leaf portion made of a magnetic material is provided between the fixed iron core and the movable iron core, and the leaf spring member plates the fixed iron core and the movable iron core. A solenoid valve having a spring force so as to be separated in a thickness direction of a spring member. 2. The solenoid valve according to claim 1, wherein the leaf spring member has a substantially disk shape having a central portion and an outer peripheral portion, and a step is provided between the central portion and the outer peripheral portion.

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