JP3635360B2 - Electromagnet, movable core of electromagnet and method of manufacturing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnet, a movable iron core that moves linearly in the electromagnet, and a method for manufacturing the movable iron core.
[0002]
[Prior art]
Conventionally, various improvements have been made in electromagnets in order to reduce hysteresis. In particular, when the movable iron core has a large runout during linear movement, the hysteresis becomes large, which degrades the performance of the electromagnet. Since the movable iron core is usually configured to have an iron core body that generates magnetic flux and a pin that is not affected by the magnetic flux, concentricity in manufacturing the iron core main body and the pin is an important issue. It was done. For example, the movable core 30 of the electromagnet shown in FIG. 6 has a pin 34 disposed and fixed in front of the core body 32 and the iron core body 32 (leftward in the figure). The core body 32 is formed with a pin hole 33 by machining, and the pin 34 is press-fitted into the pin hole 33.
[0003]
[Problems to be solved by the invention]
However, since the accuracy of the pin hole 33 formed in the movable iron core 30 is directly affected by the machine accuracy and the tool to be machined, the pin hole 33 is machined if the machine machine is inaccurate or the tool is worn. The accuracy of the pin hole 33 is deteriorated. For this reason, attention has been paid to the maintenance of machines and tools, and since high-precision products are originally processed, the processing time is long and the cost is high. Furthermore, since the oil hole 35 is separately processed in the core body 32, the processing cost of the core body 32 has only increased.
[0004]
This invention solves the above-mentioned subject, and aims at providing the movable iron core which can reduce cost while reducing hysteresis.
[0005]
[Means for Solving the Problems]
The movable iron core of the electromagnet according to the present invention is to perform the concentricity between the core body portion and the pin portion by an assembly jig without machining.
A movable iron core of an electromagnet configured to be moved in the left-right direction by excitation of a coil and configured to include an iron core main body and a pin portion disposed so as to penetrate the shaft hole of the iron core main body,
The pin portion is loosely fitted in the shaft hole of the iron core main body portion, the pin portion is disposed concentrically with the iron core main body portion, and the iron core main body portion and the pin portion are fixed by fixing means. It is characterized by being fixed.
[0006]
The method for manufacturing a movable iron core according to the present invention includes an iron core main body portion and a pin portion disposed so as to be penetrated through the shaft hole of the iron core main body portion by exciting the coil. A method of manufacturing a movable iron core of an electromagnet comprising:
In a state where the core body portion and the pin portion are loosely fitted, the pin portion is set on a movable core assembly jig that is disposed concentrically with the core body portion , and after being set, the core body portion and said pin portion is a method of manufacturing a movable core of the electromagnet, characterized in that it is fixed by fixing means.
[0007]
Further, the fixing means may be a spring pin that communicates the core body portion and the pin portion.
[0008]
The electromagnet according to the present invention is capable of sliding a movable iron core having an iron core main body and a pin portion penetrating through the shaft hole of the iron core main body in a coil body formed by winding a coil into a hollow shape. An electromagnet disposed in
The pin portion is concentrically fixed to the iron core main body in a loosely fitted state, and the pin portion is configured to be slidably supported on the coil body together with the iron core main body. It is.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0010]
FIG. 1 is a view showing a movable iron core of an electromagnet according to the present invention. A movable iron core 10 is loosely fitted in a through hole 11 and a magnetic iron core portion 12 having a through hole 11 formed in an axial center portion. And a magnetic pin part 14. The through hole 11 is machined with a tool such as a drill, and the accuracy of the hole diameter is not particularly required. There is a gap of about 2 to 3 mm between the through hole 11 and the pin 14, and the iron core portion 12 has two spring pin holes 13 in the direction perpendicular to the through hole 11 at the center thereof. Is formed. The iron core portion 12 and the pin 14 are driven into the spring pin hole 13 from the iron core portion 12 side after the concentricity of the iron core portion 12 and the pin portion 14 is determined within a predetermined range by a manufacturing method described later. Fixed by.
[0011]
The manufacturing method by assembling the movable iron core 10 is assembled using an upper jig 20 and a lower jig 25 as shown in FIGS. The upper jig 20 is formed in a rectangular shape and has a semi-cylindrical pin upper hole 21 on both sides of the lower surface side 20a and a semi-cylindrical iron core upper hole 22 between the pin upper holes 21 and 21 at the center of the lower surface side 20a. Are formed, and two rectangular opening holes 23 are formed on the upper surface side 20b so as to penetrate the upper core hole 22. In addition, bolt through holes 24 are formed at the four corners of the upper jig 20 so as to penetrate from the upper surface side 20b to the lower surface side 20a. The concentricity between the pin upper hole 21 and the iron core upper hole 22 is manufactured with extremely high accuracy.
[0012]
Similarly to the upper jig 20, the lower jig 25 is also formed in a rectangular shape and has a semi-cylindrical pin pilot hole 26 on both sides of the upper surface side 25a, and between the pin lower holes 26, 26 at the center of the upper surface side 25a. A semi-cylindrical iron core prepared hole 27 is formed. Further, tap holes 28 are formed at positions corresponding to the bolt holes 24 of the upper jig 20 at the four corners of the lower jig 25 so as to penetrate from the upper surface side 25a to the lower surface side 25b. The concentricity between the pin pilot hole 26 and the iron core pilot hole 27 is manufactured with extremely high accuracy. When the lower surface side 20a of the upper jig 20 and the upper surface side 25a of the lower jig 25 are brought into contact with each other, the same shape as that of the movable iron core 10 can be formed around the contact surface. In the same shape as the synthesized movable core 10, the roundness and concentricity of the portion corresponding to the core portion 12 and the portion corresponding to the pin portion 14 are formed with high accuracy.
[0013]
In order to assemble the movable iron core 10 with the upper jig 20 and the lower jig 21, first, the iron core portion 12 of the movable iron core 10 is inserted into the lower jig 25 into the iron core lower hole 27 of the lower jig 25, and then the pin portion 14. Is inserted into the through hole 11 of the iron core portion 12. In this case, the pin portion 14 may be inserted into the through hole 11 of the iron core portion 12 in advance and then inserted into the pin hole 26 and the iron core lower hole 27. After the iron core portion 12 and the pin portion 14 are set in the lower jig 25, the upper surface of the lower jig 25 is aligned with the iron core upper hole 22 and the pin upper hole 21 of the upper jig 20 aligned with the iron core portion 12 and the pin portion 14. The side 25a and the lower surface side 20a of the upper jig are brought into contact with each other. Then, four bolts (not shown) are inserted into the bolt holes 24 formed at the four corners of the upper jig 20, and are respectively screwed and fixed to the tap holes 28 formed at the four corners of the lower jig 25. Then, when the spring pin 16 is driven into the spring pin hole 13 formed in the iron core portion 12 of the movable iron core 12 from the two opening holes 23 formed in the upper jig 20 to fix the iron core portion 12 and the pin portion 14. As shown in FIG.
[0014]
When the bolts fixing the upper jig 20 and the lower jig 25 are removed, the upper jig 20 is removed and the movable iron core 10 is taken out, the movable iron core 10 in the state shown in FIG. It is completed while maintaining the concentricity within 14 predetermined ranges.
[0015]
Next, an embodiment in which the movable iron core 10 is incorporated in an electromagnet, particularly an electromagnetic proportional solenoid will be described.
[0016]
FIG. 4 is a cross-sectional view showing an embodiment of an electromagnetic proportional solenoid. The electromagnetic proportional solenoid S includes a main body case 1, a coil body 3 disposed in the main body case 1, and a coil body 3. A fixed iron core 4, a pipe 5, a magnetic shielding member 6 disposed between the fixed magnetic pole 4 and the pipe 5, and a movable iron core 10 slidably disposed in the pipe 5. The
[0017]
The main body case 1 is formed in a cylindrical shape with one opening, and a magnetic yoke 2a, 2b, 2c constituting an outer peripheral circuit body and a resin portion 1a formed in a part of the outer peripheral portion are integrated. The resin portion 1a is provided with a bushing for protecting a lead wire connected to a coil described later. The right end of the main body case 1 is formed with a closed portion 1b having a protruding portion. In addition, a coil body 3 including a hollow bobbin 3a sandwiched between the yokes 2a and 2c and a coil 3b wound around the bobbin 3a is disposed in the hollow portion formed inside. Has been.
[0018]
In the inner periphery of the bobbin 3a, a fixed iron core 4 is disposed on the left side in FIG. 4, and a male screw 4a is formed on the outer periphery of the left end of the fixed iron core 4. For example, it is connected to a hydraulic circuit body to which an electromagnetic proportional solenoid S is attached. It has come to be. A concave portion 4b is formed at the right end of the fixed iron core 4 so that the iron core portion 12 of the movable iron core 10 is slidably fitted, and a tapered horizontal characteristic forming portion 4c is formed at the outer peripheral end of the concave portion 4b. Is formed. In particular, by forming the horizontal characteristic forming portion 4c, the horizontal characteristic forming portion 4c serves as a proportional solenoid capable of linearly expressing the relationship between current and attractive force. Also, a movable core support hole 4d through which the pin portion 14 of the movable core 10 passes in the axial direction is formed in the inner central portion of the fixed core 4, and the pin portion 14 is slidably supported via the bearing 7. Yes. Furthermore, one oil hole 4e is formed in parallel with the movable iron core support hole 4d, and an external lubrication path is configured to hold the sliding portion of the movable iron core 10 for a long period of time.
[0019]
Further, the inner periphery of the bobbin 3a is arranged between the fixed iron core 4 and the pipe 5 at the central portion of the inner periphery of the bobbin 3a and the pipe 5 fixedly arranged in the right direction of the fixed iron core 4. A nonmagnetic magnetic shielding member 6 and the fixed iron core 4 are integrally formed and disposed. The movable iron core 10 is slidably fitted in the pipe 5 and is movably disposed in the left-right direction by being sucked by the fixed iron core 4.
[0020]
A movable core support hole 1c having a smaller diameter than the inner periphery of the pipe 5 is formed inside the closed portion 1b at the right end of the main body case 1 so that the pin portion 14 of the movable core 10 is inserted. The pin portion 14 is slidably supported through the bearing 7 in the movable iron core support hole 1c. In order to smoothly move the movable core 10 from side to side, it is desirable that the outer peripheral surface of the core portion 12 of the movable core 10 and the inner peripheral surface of the pipe 5 have a gap of about 0.2 to 0.3 mm.
[0021]
Furthermore, a spacer 8 formed of a nonmagnetic material is disposed around the outer periphery of the pin portion 12 of the movable iron core 10 on the inner end face of the concave portion 4b of the fixed iron core 4, and when the coil 3b is de-energized, it remains. The magnetism is prevented from flowing to the iron core portion 12. As shown in FIG. 5, the spacer 8 is formed in a thin cylindrical shape, and four semicircular passage portions 8a through which oil passes are formed.
[0022]
Lubricating oil supplied to the movable iron core from the outside of the electromagnetic proportional solenoid S passes through the oil hole 4e and the movable iron core support hole 4d of the fixed iron core 4 and flows into the pipe 5 through the passage portion 8a of the spacer 8, Furthermore, it flows into the movable core support hole 1 c of the main body case 1 through the through hole 11 of the core portion 12. The sliding portion between the bearing 7 and the pin portion 14 of the movable iron core 10 and the sliding portion between the pipe 5 (including the magnetic shielding member 6 and the recessed portion 4b of the fixed iron core 4) and the iron core portion 12 are lubricated. . Further, an O-ring 9 is provided on the inner peripheral surface of the closed portion 1b of the main body case 1 and the outer peripheral surface of the pipe 5 to prevent the oil lubricated in the movable iron core 10 from leaking to the outside.
[0023]
When the electromagnetic proportional solenoid S configured as described above is energized and energized to the coil 3 b, magnetic flux flows through the yokes 2 a, 2 b, 2 c, the fixed iron core 4, and the iron core portion 12 of the movable iron core 10, Is attracted to the fixed iron core 4 and is moved to the left in FIG. When the coil is de-energized and de-energized, the magnetic flux disappears, and the movable iron core 10 is moved to the right and returned by a coil spring (not shown) in the circuit body in which the electromagnetic proportional solenoid S is incorporated.
[0024]
At the time of this movement, the concentricity between the iron core portion 12 and the pin portion of the movable iron core 10 is already assembled with high accuracy. Since the guide for the movement of the movable core 10 is performed between the bearing 7 and the pin portion 14 of the movable core 10, the core portion 12 and the pipe 5 (including the inside of the magnetic shielding member 6 and the recessed portion 4b of the fixed core 4). The state of the gap between the two is stable without any particular load. Therefore, the hysteresis becomes small.
[0025]
The inflow path of the lubricating oil is as described above, and the through hole 11 formed in the movable iron core 10 can be used as an oil hole. In particular, the fact that the oil hole is provided in the central portion of the iron core portion 12 is more stable than the type in which the oil hole is provided on both sides of the through hole 11 so that the flow of magnetic flux is more stable. It has a big influence on making it smaller.
[0026]
Note that the movable iron core of the present invention is designed so that the concentricity between the iron core portion and the pin portion is not machined but is assembled at the time of assembly. It is not limited to. For example, a guide bush based on the outer periphery of the iron core portion 12 is applied to both sides of the iron core portion 12, the pin portion 14 is inserted into the guide bush, and then fixed with a spring pin 16, and then the guide bush is removed. You may do it.
[0027]
Further, the iron core portion 12 and the pin portion 14 may be fixed by using bolts from both sides instead of the spring pin 16.
[0028]
Furthermore, it is needless to say that the electromagnet using the movable iron core may be a general electromagnet instead of the electromagnetic proportional solenoid of the above-described form.
[0029]
【The invention's effect】
According to the present invention, the movable iron core of the electromagnet of the present invention is
An iron core main body and a pin portion disposed so as to penetrate through the shaft hole of the iron core main body portion, and the pin portion is loosely fitted in the shaft hole of the iron core main body portion, and Since the pin portion is disposed concentrically with respect to the core body portion, and the core body portion and the pin portion are fixed by a fixing means, the shaft hole formed in the movable core is particularly a hole-shaped machining Does not require accuracy. Further, since the shaft hole can also serve as an oil hole, the hysteresis can be reduced and the manufacturing cost of the movable iron core can be greatly reduced.
[0030]
Further, according to the method for manufacturing a movable core of the present invention, the core includes a core body and a pin portion disposed so as to penetrate through the shaft hole of the core body, and the core body and the core With the pin part loosely fitted, the concentricity of the iron core body part and the pin part can be assembled within a predetermined range by an assembling jig. For this reason, the hysteresis can be reduced and the cost can be reduced without manufacturing a high-cost movable iron core by machining.
[0031]
Furthermore, the electromagnet of the present invention has a movable iron core slidably disposed having an iron core main body portion and a pin portion penetrating through the shaft hole of the iron core main body portion, and the pin portion is an iron core main body portion. The pin portion is supported so as to be slidable. Therefore, the sliding portion of the iron core main body can move stably without any particular load, and the hysteresis can be reduced.
[Brief description of the drawings]
1 is a cross-sectional view of a movable iron core showing an embodiment of the present invention. FIG. 2 is a perspective view showing a method for manufacturing the movable iron core in FIG. 1. FIG. 3 is an assembled cross-sectional view in FIG. FIG. 5 is a sectional view of an electromagnetic proportional solenoid using a movable iron core in FIG. 5 is a diagram showing a spacer in FIG. 4. FIG. 6 is a sectional view showing a conventional movable iron core.
DESCRIPTION OF SYMBOLS 1 ... Main body case 3 ... Coil body 3b ... Coil 4 ... Fixed iron core 7 ... Bearing 10 ... Movable iron core 11 ... Through-hole (shaft hole)
12 ... Iron core (core body)
14 ... pin portion 16 ... spring pin (fixing means)
20 ... Upper jig 25 ... Lower jig

Claims (5)

A movable iron core of an electromagnet configured to be moved in the left-right direction by excitation of a coil and configured to include an iron core main body and a pin portion disposed so as to penetrate the shaft hole of the iron core main body ,
The pin portion is loosely fitted in the shaft hole of the iron core main body portion, the pin portion is disposed concentrically with the iron core main body portion, and the iron core main body portion and the pin portion are fixed by fixing means. Electromagnet movable iron core characterized by being fixed. A method of manufacturing a movable iron core of an electromagnet configured to include a pin body portion that is moved in the left-right direction by excitation of a coil and disposed so as to penetrate through a shaft hole of the core body portion. ,
In a state where the core body portion and the pin portion are loosely fitted, the pin portion is set on a movable core assembly jig that is disposed concentrically with the core body portion , and after being set, the core body portion A method for manufacturing a movable iron core of an electromagnet, wherein the pin portion is fixed by a fixing means.   2. The movable iron core according to claim 1, wherein the fixing means is a spring pin that allows the iron core body and the pin to communicate with each other.   The method for manufacturing a movable iron core of an electromagnet according to claim 2, wherein the fixing means is a spring pin that allows the iron core body and the pin to communicate with each other. An electromagnet in which a movable iron core having a core body portion and a pin portion penetrating through a shaft hole of the iron core main body portion is slidably disposed in a coil body that is wound and formed in a hollow shape. ,
An electromagnet characterized in that the pin portion is concentrically fixed to the iron core main body in a loosely fitted state, and the pin portion is supported so as to be slidable with the coil body together with the iron core main body. .

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