JPH10332026A - Electromagnet structure of solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce magnetic resistance and to improve magnetic efficiency by constituting a magnetic frame by combining a plural number of magnetic frame bodies made of continuous upper, lower, left and right piece parts and using this magnetic frame. SOLUTION: An upper side part 38 and a lower side part 41 of each of magnetic frame bodies 35, 36 are closely engaged with an engaging groove 46 of a flange part 48 on the upper side of a bobbin 25 and an engaging groove 47 of a flange part 49 on the lower side of the bobbin 25. Thereafter, an upper ring is fitted on an outer periphery of a circular arc projected part 38c' of an upper side part 38 of each of the magnetic frame bodies 35, 36, and a lower ring is fitted on an outer periphery of a circular arc projected part 41c' of a lower side part 41 of each of the magnetic frame bodies 35, 36. Consequently, the first magnetic frame body 35 and the second magnetic frame body 36 are combined on an outer surface of a guide pipe and constitute a magnetic frame. Thereafter, a circular arc part 38c of the upper side part 38 of each of the magnetic frame bodies 35, 36 is arranged in the neighbourhood of a fixed iron core, and the lower side part 41 of each of the magnetic frame bodies 35, 36 is arranged in the neighbourhood of a movable iron core.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electromagnet structure for a solenoid valve.

[0002]

2. Description of the Related Art A conventional electromagnet for a solenoid valve is shown in FIG.
As shown in (a) to (d), the fixed iron core 7 is disposed in the bobbin 25 of the exciting coil 5 whose outer periphery is surrounded by the magnetic frame 3, and the bobbin
The movable iron core 8 attracted to the fixed iron core 7 by the excitation of the excitation coil 5 is movably disposed in the inside 25.
-27137). As shown in FIGS. 4B and 4C, the magnetic frame 3 of the electromagnet 2 for a solenoid valve is composed of a single rectangular magnetic frame component, and the left and right bent portions of the bottom plate 15 are formed.
It is formed by bending at right angles at 18 and bending the left and right side plate portions 16 at right and left bent portions 19 to form a top plate portion 17.
Both ends (both ends of the top plate 17) of the magnetic frame constituting piece are separated, and a slit 22 for removing eddy current is formed between the both ends. An arc-shaped notch 23a is formed at both ends of the top plate portion 17, and the guide pipe 6 is formed by the notches 23a on both sides.
Through hole 23 is formed. Bottom plate 15
A through hole 20 for inserting the guide pipe 6 is formed at a central portion of the hole, and a slit 21 for removing an eddy current is formed from the through hole 20 to the left and right.

As shown in FIG. 4 (a), a sleeve portion of the auxiliary magnetic frame 4 is fitted into a center hole of a bobbin 25 around which the exciting coil 5 is wound from above and below. The flange portions are joined to the upper surface and the lower surface of the bobbin 25, respectively. A combined body of the exciting coil 5 and the bobbin 25 is disposed inside the magnetic frame 3, and a flange of the auxiliary magnetic frame 4 is joined to a lower surface of the top plate 17 and an upper surface of the bottom plate 15. The auxiliary magnetic frames 4 have a function of improving magnetic efficiency, and each auxiliary magnetic frame 4 is formed with a slit 4a. The inner hole of the sleeve of each auxiliary magnetic frame 4 and the inner hole of the bobbin 25
The guide pipe 6, which is placed on the same axis as 23, and in which the fixed core 7 has been fitted on the upper part in advance, is inserted through the through hole 20, and the upper part of the guide pipe 6 is projected from the through hole 23. The guide cover 6 and the fixed core 7 are fixed to the magnetic frame 3 by fitting and deforming the fixing cover 12 to the upper part of the guide pipe 6.

A lower end of the guide pipe 6 is inserted into an inner hole of the nut 13, and a flange at the lower end of the guide pipe 6 is
The O-ring 26 is placed on the step at the lower end of the central screw hole of the valve body 1 and the nut 13 is screwed into the central screw hole. Thus, the electromagnet 2 is connected to the upper part of the valve body 1, and the space between the inner surface of the guide pipe 6 and the step of the valve body 1 is sealed by the O-ring 26. A movable iron core 8 is disposed inside the guide pipe 6 so as to be movable up and down.
The valve body 9 at the lower end of the movable core 8 is urged toward a valve seat 10 of the valve body 1 by a spring 11 mounted between the movable core 8 and the movable core 8. When the exciting coil 5 is excited, the movable core 8 is attracted and moves upward, and the solenoid valve is opened. When the exciting coil 5 is degaussed, the movable iron core 8 moves downward by the elastic force of the spring 11, and the solenoid valve closes. Note that reference numeral 30 denotes an entrance-side port, and 31 denotes an exit-side port. Further, as shown in FIG. 4D, power supply terminal holes 27 and 28 and a ground terminal hole 29 are formed in the side plate portion 16 of the magnetic frame 3.

Next, disadvantages of the conventional electromagnet for a solenoid valve will be described. Regarding Transfer of Magnetic Flux at End of Magnetic Frame The magnetic continuation part between the upper end of the magnetic frame 3 forming the magnetic path and the fixed core 7 and the magnetic continuation part between the lower end of the magnetic frame 3 and the movable core 8 are: Since the magnetic path cross-sectional area of each continuation portion is smaller than that of the other portions of the magnetic frame 3, the magnetic resistance is large. Therefore, the auxiliary magnetic frame 4 is provided in each magnetic continuation section to reduce the magnetic resistance and improve the magnetic efficiency. However, the provision of the auxiliary magnetic frame 4 increases the number of parts and increases the cost. . Eddy current countermeasures To prevent the generation of eddy currents, slits are provided on the mating surface (top plate 17) of the magnetic frame 3, the bottom plate 15 of the magnetic frame 3, and the auxiliary magnetic frame 4, respectively. In this case, the slit 4a of the auxiliary magnetic frame 4 is connected to the slit 22 of the mating surface and the bottom plate 15
The generation of an eddy current can be completely prevented if the slit 21 and the slit 21 completely overlap each other in the vertical direction. However, if the overlapping state is incomplete, the generation of the eddy current cannot be completely prevented. Magnetic Efficiency As shown in FIG. 4D, power supply terminal holes 27 and 28 and a ground terminal hole 29 are formed in the side plate portion 16 of the magnetic frame 3.
A portion having a small magnetic flux passage area is generated, and the magnetic efficiency is reduced. Plate Thickness and Bending R of Magnetic Frame When the radius R (bending R) of the bent portions 18 and 19 of the magnetic frame 3 is reduced for miniaturization, cracks enter the outside of the bent portions 18 and 19 to cause magnetic leakage. The amount increases. For this reason, the bending R has to be increased, and the magnetic frame 3 becomes larger than necessary. Adhesion between Magnetic Frame 3 and Filling Resin The contact surface between magnetic frame 3 and filling resin is wide, and if adhesion failure occurs, temperature rise of excitation coil 5 and insulation failure occur.

[0006]

According to the present invention, there is provided an electromagnet structure for an electromagnetic valve, comprising a plurality of magnetic frames each having a continuous upper, lower, left and right side portion being combined to constitute a magnetic frame. It is an object to eliminate the above-mentioned disadvantages.

[0007]

According to the present invention, in order to achieve the above object, a fixed core is disposed in a bobbin of an exciting coil whose outer periphery is surrounded by a magnetic frame, and the fixed core is energized in the bobbin by exciting the exciting coil. In the electromagnet structure for an electromagnetic valve in which a movable iron core is movably disposed, the magnetic frame is configured by combining a plurality of magnetic frames, and each magnetic frame is an upper side, a first side, and a lower side. And a central part of the upper side and the lower side is an arcuate part in an arc shape in a top view, and straight parts on both sides of the upper side and the lower side arc part. Are formed so as to form a predetermined angle with each other when viewed from above, and the first configuration is such that the bobbins are mounted between the upper side and the lower side of each magnetic frame. According to the present invention, in the first configuration, the arc portion of the upper side of each magnetic frame body is arranged close to the fixed iron core, the lower side portion of each magnetic frame body is arranged close to the movable iron core, and the upper side and the lower side are bobbin. A ring is fitted to an outer peripheral portion of an arc portion of an upper side portion of each magnetic frame body that is engaged with an engagement groove on an outer surface of the flange portion, and a lower side portion of each magnetic frame body that protrudes downward. The fact that the ring is fitted to the outer peripheral portion of the circular arc portion is referred to as a second configuration. According to the present invention, in the first configuration or the second configuration, the angles formed by the linear portions on both sides of the arc portion on the upper side and the lower side in the top view are approximately 90 ° and approximately 180 °.
Alternatively, the angle of approximately 60 ° is referred to as a third configuration.

[0008]

1 and 2 show a first embodiment of an electromagnet structure for a solenoid valve according to the present invention. 1 and 2, the same members as those of the conventional example of FIG. 4 are denoted by the same reference numerals as those of FIG. 4, and the description thereof will be simplified or omitted. As shown in FIGS. 1 and 2, the magnetic frame 3 is configured by combining a first magnetic frame 35 and a second magnetic frame 36 that are symmetrical left and right.
Reference numeral 36 denotes an integrated frame body including an upper side portion 38, a first side portion 39, a lower side portion 41, and a second side portion 40. And each magnetic frame 35
The central portion of the upper side portion 38 and the lower side portion 41 of the 36 are arcuate arc portions 38c and 41c in a top view, and the straight portions 38a and 41a on both sides of the arc portions 38c and 41c of the upper side portion 38 and the lower side portion 41. Linear part 38b
And 41b are formed so as to form an angle of about 90 degrees with each other when viewed from above. The upper surfaces of the arc portions 38c of the magnetic frames 35 and 36 project upward to form projections 38c ', and the lower surfaces of the arc portions 41c project downward to form projection portions 41c'.

Two engagement grooves 46 are formed in the upper surface of the upper flange portion 48 of the bobbin 25. The engagement grooves 46 are similarly formed in the lower surface of the lower flange portion 49 of the bobbin 25. Is 2
Individually formed. The arc portions 46c and 47c inside the fan-shaped engagement grooves 46 and 47 and the straight portions 46a and 47a and 46b on both sides when viewed from above.
・ The shape of 47b is the upper part 38 and the lower part of each magnetic frame 35 ・ 36
It matches the outer shape of top view 41. The upper side portion 38 and the lower side portion 41 of each of the magnetic frames 35 and 36 are inserted into the engagement groove 46 of the upper flange portion 48 of the bobbin 25 and the engagement groove 47 of the lower flange portion 49 of the bobbin 25.
Are brought into the state shown in FIG. 1 (b). Next, the upper ring 43 is fitted on the outer periphery of the arc-shaped projection 38c 'of the upper side 38 of each magnetic frame 35, 36, and each magnetic frame 35
The lower ring 44 is attached to the outer periphery of the arc-shaped projection 41c '
Are fitted together, the first magnetic frame 35 and the second magnetic frame 36 are combined with the outer surface of the guide pipe 6 to form the magnetic frame 3, and the first magnetic frame 35 and the second magnetic frame 36 Is maintained at the combination position (see FIG. 1 (a)). The circular arc portion 38c of the upper side portion 38 of each of the magnetic frames 35 and 36 is arranged close to the fixed core 7, and the lower side 41 of each of the magnetic frames 35 and 36 is arranged close to the movable core 8.

As shown by a one-dot chain line 51 in FIG. 1B, when the outer circumferences of the magnetic frame 3 and the exciting coil 5 are covered with resin by resin molding, a substantially cubic electromagnet 2 is completed. Four linear portions of the upper side portion 38 of the first magnetic frame 35 and the second magnetic frame 36
38a and 38b are substantially right angles, the resin thickness is relatively uniform, and the amount of resin used is small. FIG. 1 (a)
As shown in FIG. 7, an annular engaging portion 52 is formed at the lower end of the movable core 8, and a spring 11 is mounted between the annular engaging portion 52 and a flange at the lower end of the guide pipe 6. 8 are biased downward. Each of the magnetic frames 35 and 36 is made of a magnetic material and is shown as a single plate in the figure, but it may be made by stacking a large number of thin silicon steel plates or the like. In the case of a single plate or a plurality of plates, a flat plate is formed into a frame by plastic working, and the magnetic frames 35 and 36 can be easily obtained by bending the plate.
In addition, as shown in FIG.
Numeral 54 directly adheres to the side surface of the second side 40 of the second magnetic frame 36, or adheres a resin plate to the second side 40 of the second magnetic frame 36, and attaches a lead wire to the resin plate. Fix it. Therefore, the magnetic frame
No power supply terminal holes are formed in 35 and 36.

FIG. 3 (a) shows a second embodiment of the electromagnet structure for a solenoid valve according to the present invention. In the second embodiment, the linear portions 38a and 41a of the first magnetic frame 35 and the second magnetic frame 36 are connected to the linear portions.
38b and 41b are formed so as to form an angle of approximately 180 degrees with each other in a top view, and the linear portions 38a and 38b of the first magnetic frame 35 are formed.
38b and the linear portions 38b and 38a of the second magnetic frame 36 are joined. Since the circular arc portions 38c and 41c of the first magnetic frame 35 and the circular arc portions 38c and 41c of the second magnetic frame 36 surround the entire circumference of the fixed iron core 7 and the movable iron core 8, the area of the magnetic continuation portion is reduced. growing. Other features of the second embodiment are the same as those of the first embodiment.

FIG. 3 (b) shows a third embodiment of the electromagnet structure for a solenoid valve according to the present invention. In the third embodiment, the magnetic frame 37 is composed of six magnetic frames 37, and the linear portions 38a and 41a of each magnetic frame 37 are formed.
And the linear portions 38b and 41b are formed so as to form an angle of approximately 60 degrees with each other in a top view, and the linear portions 38a and
38b and the linear portions 38b and 38a of the adjacent magnetic frame are joined. Since the arc portions 38c and 41c of the six magnetic frames 37 surround the entire periphery of the fixed iron core 7 and the movable iron core 8, the area of the magnetic continuity increases. Other features of the third embodiment are the same as those of the first embodiment.

[0013]

According to the first and second aspects of the present invention, the following effects are obtained. Regarding the transfer of magnetic flux at the end of the magnetic frame, the inside of the arc on the upper side of the magnetic frame is a magnetic continuation section, and the arc is longer than the straight section on the upper side, the first side and the second side. And the width of the arc portion can be widened, so that the magnetic path cross-sectional area of the magnetic continuation portion is considerably larger than that of the conventional frame. Therefore, even if the conventional auxiliary magnetic frame is omitted, the magnetic resistance is small and the magnetic efficiency is high. About eddy current countermeasures Since the magnetic frame is not continuous in the circumferential direction, there is no eddy current circulating circuit, and eddy current can be prevented from being generated. Magnetic efficiency The magnetic frame is an integral frame consisting of an upper side, a first side, a lower side, and a second side. A conventional power supply terminal hole and a ground terminal hole are formed in the magnetic frame. Therefore, there is no portion having a small magnetic flux passage area, and the magnetic efficiency is high. Plate Thickness and Bending R of Magnetic Frame The bent portion of the magnetic frame is a circular arc when viewed from above, and the radius of the circular arc is considerably large, so that the problem of the bending R of the bent portion of the conventional example does not occur. . Adhesion between Magnetic Frame 3 and Filling Resin The surface area of the magnetic frame is small and the contact surface with the filling resin is small as compared with the conventional example, so that the problems of temperature rise and insulation failure are eliminated.

[Brief description of the drawings]

FIG. 1 (a) is a longitudinal sectional view of an electromagnetic valve using an electromagnet structure for an electromagnetic valve according to a first embodiment of the present invention (A- FIG. 1 (b)).
1 (b) is a sectional view taken along line BB of FIG. 1 (a).

FIG. 2A is a front view (as viewed from the left side of FIG. 2B) of the magnetic frame used in the first embodiment of the present invention, and FIG. 2A is a top view, FIG. 2C is a top view of the bobbin used in the first embodiment of the present invention, and FIG. 2D is DOD ′ of FIG. 2C. It is a line sectional view.

FIG. 3 (a) is an explanatory diagram of an electromagnet structure for a solenoid valve according to a second embodiment of the present invention, and FIG. 3 (b) is an electromagnet structure for a solenoid valve according to the third embodiment of the present invention. FIG.

FIG. 4 (a) is a longitudinal sectional view of a solenoid valve using the conventional electromagnet structure for a solenoid valve, and FIG. 4 (b) is a front view of the magnetic frame of FIG. 4 (a). 4 (c) is a top view of the magnetic frame, and FIG. 4 (d) is a side view of the magnetic frame shown in FIG. 4 (a).

[Explanation of symbols]

 Reference Signs List 3 magnetic frame 5 excitation coil 7 fixed core 8 movable iron core 25 bobbin 35 first magnetic frame 36 second magnetic frame 37 magnetic frame 38 upper side 38a linear section 38b linear section 38c arc section 39 first side section 40 first 2 side 41 Lower side 41a Straight 41b Straight 41c Circular

Claims (3)

[Claims] An electromagnetic valve having a fixed core disposed in a bobbin of an excitation coil whose outer periphery is surrounded by a magnetic frame, and a movable core attracted to the fixed core by excitation of the excitation coil in the bobbin so as to be movable. In the electromagnet structure for use, the magnetic frame is configured by combining a plurality of magnetic frames, and each magnetic frame is an integrated frame including an upper side, a first side, a lower side, and a second side. The central part of the upper side part and the lower side part is an arcuate part in an arc shape in a top view, and the straight parts on both sides of the upper side part and the arc part of the lower side part are formed so as to form a predetermined angle with each other in a top view, An electromagnet structure for a solenoid valve, wherein a bobbin is mounted between an upper side and a lower side of each magnetic frame. 2. An arc portion on an upper side of each magnetic frame body is disposed close to a fixed iron core, a lower side portion of each magnetic frame body is disposed close to a movable iron core, and upper and lower sides are outer surfaces of a bobbin flange. The ring is fitted to the outer peripheral portion of the arc portion of the upper side of each magnetic frame body that is engaged with the engaging groove of The electromagnet structure for a solenoid valve according to claim 1, wherein a ring is fitted to the outer peripheral portion. 3. An angle between the straight portions on both sides of the upper and lower arc portions when viewed from above is approximately 90 °, approximately 180 °, or approximately 6 °.
3. The electromagnet structure for a solenoid valve according to claim 1, wherein the angle is 0 [deg.].