JP2016004801A - Solenoid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase an attraction force acting on a mover relatively without causing any up-sizing, while enhancing reliability, in a solenoid having a self-holding function for holding the mover.SOLUTION: A solenoid includes a cylindrical coil 1 generating a first magnetic flux M1 upon electrification, a yoke 2 forming a magnetic circuit, through which the first magnetic flux M1 flows, on the periphery of the coil 1, a magnet 3 facing the end face of the coil 1, while coming into contact with the inner periphery 2b1 of the yoke 2, and disposed while spaced apart by a predetermined distance from the outer peripheral member 2a of the yoke 2 in the radial direction, and generating a second magnetic flux M2 flowing through the magnetic circuit in the opposite direction from the first magnetic flux M1, and a mover 4 of magnetic material facing the magnet 3, and disposed to be able to contact with the outer peripheral member 2a, while spaced apart by a predetermined distance from the magnet 3 in the axial direction.

Description

  The present invention relates to a solenoid having a self-holding function for holding a mover.

As a type of solenoid, one disclosed in Patent Document 1 is known. As shown in FIG. 1 of Patent Document 1, the solenoid 8 of Patent Document 1 includes an exciting coil 10, a magnetic plunger 9, a permanent magnet 19, and a fixed iron core 18 disposed on the inner peripheral surface of the exciting coil 10. I have. The plunger 9 is held at a position where the end surface of the plunger 9 and the end surface of the fixed iron core 18 abut against each other by the attractive force generated by the permanent magnet 19. In this case, the attractive force acting on the plunger 9 is determined by the density of the magnetic flux generated by the permanent magnet 19 (magnetic flux density) and the area where the magnetic flux acts (attraction area). This adsorption area is determined by the area of the end surface of the plunger 9 that faces the end surface of the fixed iron core 18.
Here, in order to increase the attractive force acting on the plunger 9, the area of the end surface of the plunger 9 is increased because the plunger 9 is disposed inside the inner peripheral surface of the excitation coil 10. Since the diameter of 10 needs to be increased, the size of the coil 2 is affected. Further, increasing the magnetic flux density of the permanent magnet 19 to increase the attractive force acting on the plunger 9 affects the cost.

  On the other hand, what is shown by patent document 2 is known as one type of solenoid. As shown in FIG. 1 of Patent Document 2, the solenoid 1 of Patent Document 2 is movable on the inner side of the solenoid coil 2, the magnetic body 16 disposed at the front end of the solenoid coil 2, and the solenoid coil 2. A disc-shaped magnet assembly 30 is provided which is fixed to the plunger 20 so as to face the arranged plunger 20 and the magnetic body 16. The plunger 20 is held by the attractive force of the magnet assembly 30 and the magnetic body 16 at a position where the magnet assembly 30 and the magnetic body 16 are in contact with each other. Since the magnet assembly 30 is disposed not to the inside of the solenoid coil 2 but to face the front end of the solenoid coil 2 on which the magnetic body 16 is disposed, regardless of the size of the solenoid coil 2, the magnet assembly 30 is magnetized. The area (adsorption area) where the assembly 30 and the magnetic body 16 come into contact can be made relatively large. As described above, the solenoid 1 can relatively increase the attractive force between the magnetic body 16 and the magnet assembly 30 without increasing the size of the coil 2.

Japanese Patent No. 4277719 Japanese Patent No. 1842066

  However, in the solenoid 1 described in Patent Document 2 described above, since the plunger 20 and the magnet assembly 30 are fixed, the magnet assembly 30 moves as the plunger 20 moves. Therefore, since the impact generated when the plunger 20 moves and the magnet assembly 30 and the magnetic body 16 contact each other directly acts on the permanent magnet 32 constituting the magnet assembly 30, the permanent magnet 32 is cracked. May occur. The impact on the permanent magnet 32 affects the reliability of the solenoid 1.

  Accordingly, the present invention has been made to solve the above-described problems, and in a solenoid having a self-holding function for holding the mover, the suction force acting on the mover is made relatively large without causing an increase in size. At the same time, it aims to improve reliability.

In order to solve the above problems, a solenoid according to claim 1 includes a first surface, a second surface different from the first surface, an outer peripheral surface extending from a radially outer peripheral surface, and a radially inner peripheral surface. A cylindrical coil that generates a first magnetic flux when energized, an outer peripheral portion that extends along the outer peripheral surface of the coil, and an inner peripheral surface that extends along the inner peripheral surface of the coil. An inner peripheral portion and a connecting portion that extends along the first surface of the coil and connects one end portion of the outer peripheral portion and one end portion of the inner peripheral portion to form a magnetic circuit through which the first magnetic flux flows. The yoke faces the second surface of the coil, contacts one of the outer peripheral portion and inner peripheral portion of the yoke, and is predetermined in the radial direction of the coil from the other of the outer peripheral portion and inner peripheral portion of the yoke. A second magnetic flux that is arranged at a distance and flows through the magnetic circuit in a direction opposite to the direction in which the first magnetic flux flows. And a mover made of a magnetic material facing the magnet and capable of contacting the other of the outer peripheral portion and the inner peripheral portion of the yoke and spaced apart from the magnet in the axial direction of the coil by a predetermined distance. The mover has a first position in contact with the other of the outer peripheral portion and the inner peripheral portion of the yoke, and the other of the outer peripheral portion and the inner peripheral portion of the yoke. In the axial direction, when moving between the second position further away from the first position and the mover is located at the first position, the mover is generated by the second magnetic flux when the coil is not energized. If the coil is not energized and the mover is held in the first position by the first suction force, the first suction force is maintained. Is made for the mover When a predetermined external force smaller than the first attractive force acts on the mover by the external member in a direction opposite to the direction in which the first attracting force is applied, the coil is energized to generate the first magnetic flux, whereby the first attractive force is smaller than the predetermined external force. When the mover is moved from the first position to the second position and the mover is located at the second position by being changed to the two attractive forces, the mover is generated by a predetermined external force by the external member and at least the second magnetic flux. When the third attraction force attracted toward the magnet acts on the mover, the predetermined external force is removed, and the second position is moved to the first position.
According to this, since the magnet is disposed so as to face the second surface of the coil and the mover is disposed so as to face the magnet, the mover is disposed inside the inner peripheral surface of the coil. Compared with the case where it has, the area (attraction | suction area) of the needle | mover which the 2nd magnetic flux produced by a magnet acts can be enlarged. Therefore, the attractive force acting on the mover can be made relatively large without increasing the size of the coil.
Further, since the magnet is not fixed to the mover, it does not move even when the mover moves, and is disposed at a predetermined distance from the mover. Thereby, the impact that occurs when the mover moves and the other of the outer peripheral portion and the inner peripheral portion of the yoke comes into contact does not directly act on the magnet. Therefore, since the occurrence of magnet breakage is suppressed, the reliability of the solenoid can be improved.

According to a second aspect of the present invention, in the solenoid according to the first aspect, a flange portion extending in a radial direction of the coil is provided at a portion where one of the outer peripheral portion and the inner peripheral portion of the yoke contacts. The outer periphery and the inner periphery of the coil are formed over the entire circumference at a predetermined distance in the radial direction of the coil.
According to this, since the area of the part which one magnet of the outer peripheral part and inner peripheral part of a yoke contacts can be enlarged by a flange part, a 2nd magnetic flux can be enlarged further. Therefore, the suction force acting on the mover can be further increased.

The invention according to claim 3 is the solenoid according to claim 1 or 2, further comprising a spring that presses the mover toward the magnet, and the pressing force of the spring is such that the mover is positioned at the first position. In this case, the magnitude of the resultant force of the pressing force of the spring and the second suction force is set to be smaller than the magnitude of the predetermined external force.
According to this, since the spring presses the mover toward the magnet, the mover can be reliably returned from the second position to the first position.

According to a fourth aspect of the present invention, in the solenoid according to any one of the first to third aspects, a non-magnetic shaft on which a predetermined external force acts is fixed to the mover.
According to this, since the shaft on which the predetermined external force acts is fixed to the mover, the predetermined external force can be reliably applied to the mover.

It is an axial direction sectional view of a solenoid in one embodiment of the present invention, and shows the state where a mover is held in the 1st position. It is an axial sectional view of the solenoid shown in FIG. 1, and shows a state where the mover is located at the second position. It is a figure which shows the attractive force which acts on the needle | mover shown in FIG. It is an axial sectional view of a solenoid in a modification of one embodiment of the present invention.

  Hereinafter, an embodiment of a solenoid having a self-holding function for holding a mover according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the solenoid 10 includes a coil 1, a yoke 2, a magnet 3, a mover 4, a shaft 5, a plurality of bearings 6, a spring 7, and a holding member 8.

  The coil 1 is a conductive wire wound in a cylindrical shape. The coil 1 includes a first surface 1a which is one end surface (left side in FIG. 1), a second surface 1b which is the other end surface (right side in FIG. 1), an outer peripheral surface 1c extending radially outward and a radial direction. It has an inner peripheral surface 1d extending inward. The coil 1 is wound around, for example, a resin bobbin (not shown). Both ends of the conducting wire are drawn out of the solenoid 10 and connected to a current control device (not shown). The current control device controls a direct current supplied to the coil 1. Specifically, the current control device performs control for supplying or interrupting a direct current to the coil 1. Further, the coil 1 is energized to generate a first magnetic flux M1 indicated by a broken line in FIG.

  The yoke 2 forms a magnetic circuit. The yoke 2 is formed of a magnetic material such as iron and includes an outer peripheral member (outer peripheral portion of claims) 2a, a base member 2b, and a flange member 2c as shown in FIG. The outer peripheral member 2 a is formed in a cylindrical shape extending along the outer peripheral surface 1 c of the coil 1. The base member 2b includes a cylindrical inner peripheral portion 2b1 extending along the inner peripheral surface 1d of the coil 1 and an end surface portion extending along the first surface 1a of the coil 1 (the connecting portion in the claims). 2b2. An opening peripheral edge of one end portion (left end portion in FIG. 1) of the inner peripheral portion 2b1 and an inner peripheral edge of the end surface portion 2b2 are continuously formed. Moreover, the outer periphery of the end surface part 2b2 and the opening part periphery of the one end part (left side edge part of FIG. 1) of the outer peripheral member 2a are joined (connected) by caulking, for example. Thus, the end surface portion 2b2 connects the one end portion of the outer peripheral member 2a and the one end portion (the left end portion in FIG. 1) of the inner peripheral portion 2b1. Further, the outer peripheral member 2 a and the end surface portion 2 b 2 constitute an outer shell of the solenoid 10.

  The flange member 2c includes a flange portion 2c1 and a cylindrical portion 2c2. The flange portion 2c1 is formed over the entire circumference so as to extend radially outward from the other end (the right end in FIG. 1) of the inner peripheral portion 2b1. The flange portion 2c1 is formed at a predetermined distance from the outer peripheral member 2a in the radial direction. Specifically, the first gap G1 is provided so that the outer peripheral surface of the flange portion 2c1 and the inner peripheral surface of the outer peripheral member 2a are separated by a predetermined distance. The first gap G1 is set to such a size that the magnetic flux flowing in the magnetic circuit is not short-circuited between the flange portion 2c1 and the outer peripheral member 2a. The cylindrical part 2c2 is a part that fits with the inner peripheral part 2b1. The cylindrical portion 2c2 is fixed by being press-fitted into the inner peripheral portion 2b1, for example. The cylindrical portion 2c2 is formed so as to protrude in the axial direction from the inner peripheral edge of the flange portion 2c1. The inner peripheral surface of the cylindrical portion 2c2 and the inner peripheral surface of the inner peripheral portion 2b1 are set to be substantially the same surface. Thus, when the coil 1 is energized, the first magnetic flux M1 flows in the magnetic circuit formed by the yoke 2 in the direction indicated by the broken line in FIG.

  The magnet 3 is a permanent magnet. The magnet 3 is formed in a disc shape. As shown in FIG. 1, the magnet 3 has one surface (the left surface in FIG. 1) facing the second surface 1b of the coil 1 and is in contact with the end surface (the right end surface in FIG. 1) of the flange portion 2c1. doing. The magnet 3 and the flange portion 2c1 are fixed by adhesion, for example. The magnet 3 is disposed at a predetermined distance from the outer peripheral member 2a in the radial direction. Specifically, the second gap G2 is provided so that the outer peripheral surface of the magnet 3 and the inner peripheral surface of the outer peripheral member 2a are separated by a predetermined distance. The second gap G2 is set to a size such that the second magnetic flux M2 generated by the magnet 3 is not short-circuited between the magnet 3 and the outer peripheral member 2a. Further, as shown in FIGS. 1 and 2, the second magnetic flux M2 flows through the magnetic circuit in the direction opposite to the direction of the first magnetic flux M1. Further, the magnet 3 is formed with a through hole 3 a penetrating the shaft 5.

  The mover 4 is formed of a magnetic material such as iron. The mover 4 is formed in a disc shape. The mover 4 has one surface (the left surface in FIG. 1) facing the other surface (the right surface in FIG. 1) of the magnet 3 and the other end surface (the right end surface in FIG. 1) of the outer peripheral member 2a. It is arranged so that it can contact. The mover 4 shown in FIG. 1 represents the state located in the 1st position P1 which contacts the other end surface of the outer peripheral member 2a. The mover 4 is disposed at a predetermined distance from the magnet 3 in the axial direction. Specifically, a third gap G3 is provided so that one surface of the mover 4 and the other surface of the magnet 3 are separated from each other by a predetermined distance in the axial direction. The third gap G3 is set to such a magnitude that the impact generated by the movement of the mover 4 does not directly act on the magnet 3. In order to increase the attractive force acting on the mover 4 generated by the second magnetic flux M2, the third gap G3 is set small. Further, one end of the shaft 5 (the right end in FIG. 1) is fixed to the mover 4. For example, a female screw is formed on the mover 4, and a male screw is formed on one end of the shaft 5, and the mover 4 and the shaft 5 are fixed by the screw portion.

  The shaft 5 is formed in a cylindrical shape by a nonmagnetic material such as stainless steel. The shaft 5 is disposed inside the yoke 2 via a plurality of bearings 6 so as to be movable in the axial direction. The length of the shaft 5 is set such that the other end (the left end in FIG. 1) protrudes from the yoke 2. The bearing 6 is a slide bearing, for example.

  The spring 7 is disposed on the other surface side of the mover 4 and presses the mover 4 toward the magnet 3. The spring 7 is, for example, a coil spring. The holding member 8 constitutes the outline of the solenoid 10 and holds the spring 7. The holding member 8 is formed in a bottomed cylindrical shape by a nonmagnetic material such as stainless steel. Further, the holding member 8 is formed with a through hole 8a at the center of the bottom surface and a protruding portion 8b protruding in a cylindrical shape toward the mover 4 in the axial direction from the periphery of the through hole 8a.

  Next, the operation of the mover 4 in the solenoid 10 will be described. First, as shown in FIG. 1, the case where the mover 4 is held at the first position P1 will be described. In this case, since the coil 1 is not energized, the first magnetic flux M1 is not generated. Therefore, only the second magnetic flux M2 flows through the magnetic circuit. At this time, the first suction force F1 acts on the mover 4 in the left direction in FIG. That is, the first attraction force F1 is generated only by the second magnetic flux M2 when the mover 4 is located at the first position P1 and the coil 1 is not energized, and the mover 4 is attracted toward the magnet 3. Is the suction force F. The attractive force F is a force that is generated by at least one of the first magnetic flux M1 and the second magnetic flux M2 and attracts the mover 4 toward the coil 1 and the magnet 3.

  Further, a first pressing force Fs1 is applied to the mover 4 from the spring 7 in the left direction in FIG. The first pressing force Fs1 is a pressing force Fs from the spring 7 that acts on the mover 4 when the mover 4 is located at the first position P1. That is, the mover 4 is held at the first position P1 by the first suction force F1 and the first pressing force Fs1.

  Further, a predetermined external force Fg acts on the other end of the shaft 5 from the outside of the solenoid 10 by an external member (not shown) in the right direction in FIG. Since the shaft 5 and the mover 4 are fixed, a predetermined external force Fg acts on the mover 4. Here, when the mover 4 is located at the first position P1, the second magnetic flux M2 is set so that the resultant force of the first attractive force F1 and the first pressing force Fs1 is larger than the predetermined external force Fg (F1 + Fs1> Fg). And the spring constant of the spring 7 are set. Thereby, even when the predetermined external force Fg acts on the mover 4, the mover 4 is held at the first position P1.

  Next, the case where the mover 4 moves from the first position P1 to the second position P2 will be described. As shown in FIG. 2, the second position P2 is a position where the mover 4 is further away from the other end surface of the outer peripheral member 2a on the right side of FIG. When the mover 4 is moved from the first position P1 to the second position P2, the coil 1 is energized for a predetermined time at the current value Iα. The predetermined time is sufficient time for the mover 4 to move away from the other end surface of the outer peripheral member 2a. The predetermined time is, for example, 0.5 seconds. When the coil 1 is energized at the current value Iα, as shown in FIG. 3, the attractive force F is changed from the first attractive force F1 (point A) to the second attractive force F2 (point B) by the first magnetic flux M1. ). The second attractive force F2 is the first position attractive force Fp1 when the coil 1 is supplied with the current value Iα. The first position attractive force Fp1 is generated by at least one of the first magnetic flux M1 and the second magnetic flux M2 when the movable element 4 is located at the first position P1, and attracts the movable element 4 toward the coil 1 and the magnet 3. Is the suction force F.

  Here, the first position suction force Fp1 will be described using the graph of FIG. The first position suction force Fp1 is indicated by a solid line. The first position attractive force Fp1 changes according to the current value I applied to the coil 1. Specifically, when the coil 1 is not energized and the current value I is zero, the first position attractive force Fp1 is the above-described first attractive force F1 (point A). When the coil 1 is energized and the current value I increases from zero, the first magnetic flux M1 is generated. The first magnetic flux M1 and the second magnetic flux M2 act so that the first magnetic flux M1 cancels the second magnetic flux M2 because the directions in which the magnetic circuit flows are opposite directions (see FIG. 2). Thereby, the first position suction force Fp1 decreases from the first suction force F1 (point A). When the current value I increases from zero until the first magnetic flux M1 and the second magnetic flux M2 become equal, the first position attractive force Fp1 becomes zero (point C). Further, when the current value I increases from this state (point C), the first magnetic flux M1 becomes larger than the second magnetic flux M2, so that a first position attractive force Fp1 is generated by the first magnetic flux M1. Therefore, the first position suction force Fp1 increases from zero. That is, the second attractive force F2 (point B) changes according to the current value Iα.

  Here, the range Ih of the current value Iα is set so that the resultant force of the second suction force F2 and the first pressing force Fs1 is smaller than the predetermined external force Fg (F2 + Fs1 <F3). The range Ih is a range in which the current value Iα changes due to variations in voltage supplied to the current control device, temperature changes of the coil 1, and the like. As described above, when the coil 1 is energized, the first suction force F1 that holds the mover 4 at the first position P1 is changed to the second suction force F2. Since the resultant force with the pressing force Fs1 is smaller than the predetermined external force Fg, the mover 4 moves from the first position P1 to the second position P2.

  When the mover 4 is located at the second position P2, as shown in FIG. 2, a predetermined external force Fg and a second pressing force Fs2 larger than the first pressing force Fs1 act on the mover 4. The second pressing force Fs2 is a pressing force Fs generated when the spring 7 is compressed when the mover 4 moves from the first position P1 to the second position P2. Further, in this case, a second position suction force Fp2 (corresponding to the third suction force in the claims) acts on the movable element 4. The second position attractive force Fp2 is an attractive force F that attracts the movable element 4 generated by at least the second magnetic flux M2 toward the coil 1 and the magnet 3 when the movable element 4 is positioned at the second position P2. When the mover 4 is located at the second position P2, the mover 4 and the coil 1 and the magnet 3 are separated from each other as compared to when the mover 4 is located at the first position P1. Magnetic flux density is low. Therefore, the magnitude of the second position suction force Fp2 is equal to or less than the magnitude of the first position suction force Fp1. The second position suction force Fp2 is indicated by a one-dot broken line in FIG. Similar to the first position attractive force Fp1, the second position attractive force Fp2 changes according to the change in the first magnetic flux M1 generated by the current value I.

Moreover, in this embodiment, when the needle | mover 4 is located in the 2nd position P2, it sets so that the coil 1 may not be supplied with electricity. Thereby, the second position suction force Fp2 at the point D shown in FIG. The second position attractive force Fp2 at the point D is generated only by the second magnetic flux M2 because the current value I is zero.
Accordingly, the second position P2 is specifically the position where the resultant force of the second position suction force Fp2 and the second pressing force Fs2 and the predetermined external force Fg are balanced, or When the predetermined external force Fg is larger than the resultant force of the second position suction force Fp2 and the second pressing force Fs2, the position where the other surface of the movable element 4 abuts against the end surface 8b1 (see FIG. 2) of the protruding portion 8b, or When the external member that generates the predetermined external force Fg moves the mover 4 to the right in FIG. 2 by a predetermined amount X1, it is a position away from the first position P1 by the predetermined amount X1 in the right direction in FIG. In the present embodiment, as shown in FIG. 2, the second position P2 is a position away from the first position P1 by a predetermined amount X1 in the right direction in FIG. And the needle | mover 4 is located in the 2nd position P2, while the predetermined external force Fg is acting.

  Furthermore, the case where the needle | mover 4 returns from the 2nd position P2 to the 1st position P1 is demonstrated. As shown in FIG. 2, the mover 4 returns from the second position P2 to the first position P1 when the predetermined external force Fg is removed from the state held at the second position P2. This is because by removing the predetermined external force Fg, only the second position suction force Fp2 and the second pressing force Fs2 acting in the left direction in FIG.

According to this embodiment, the 1st surface 1a, the 2nd surface 1b different from the 1st surface 1a, the outer peripheral surface 1c which extends the circumferential surface of radial direction outer side, and the inner peripheral surface extended to the circumferential surface of radial direction inner side 1d, and a cylindrical coil 1 that generates a first magnetic flux M1 when energized, an outer peripheral member 2a that extends along the outer peripheral surface 1c of the coil 1, and an inner peripheral surface 1d of the coil 1. An inner peripheral portion 2b1 extending along the first surface 1a of the coil 1, and an end surface portion 2b2 connecting one end portion of the outer peripheral member 2a and one end portion of the inner peripheral portion 2b1. The yoke 2 that forms a magnetic circuit through which one magnetic flux M1 flows and the second surface 1b of the coil 1 are in contact with the inner peripheral portion 2b1 of the yoke 2 and the diameter of the coil 1 from the outer peripheral member 2a of the yoke 2 In the direction opposite to the direction in which the first magnetic flux M1 flows. A magnet 3 for generating a second magnetic flux M2 flowing through the air circuit, and facing the magnet 3 so as to be in contact with the outer peripheral member 2a of the yoke 2 and arranged at a predetermined distance from the magnet 3 in the axial direction of the coil 1. The movable body 4 is a solenoid 10 having a magnetic body 4, and the movable body 4 includes a first position P 1 in contact with the outer peripheral member 2 a of the yoke 2 and an outer peripheral member 2 a of the yoke 2. In the axial direction, when moving between the second position P2 further away from the first position P1 and the mover 4 is located at the first position P1, the second magnetic flux M2 when the coil 1 is not energized. The first attracting force F1 that attracts the mover 4 toward the magnet 3 is held at the first position P1, the coil 1 is not energized, and the mover 4 is first activated by the first attracting force F1. In one position P1 When held, when the predetermined external force Fg smaller than the first suction force F1 acts on the mover 4 by the external member in the direction opposite to the direction in which the first suction force F1 acts on the mover 4, the coil 1 Is generated and the first magnetic flux M1 is generated, whereby the first attractive force F1 is changed to the second attractive force F2 smaller than the predetermined external force Fg, thereby moving from the first position P1 to the second position P2. When the mover 4 is located at the second position P2, the predetermined external force Fg by the external member and the second position attraction force Fp2 generated by at least the second magnetic flux M2 and attracting the mover 4 toward the magnet 3 are movable. When acting on the child 4, the predetermined external force Fg is removed to move from the second position P2 to the first position P1.
According to this, the disk-shaped magnet 3 is disposed so that one surface thereof faces the other end surface of the coil 1, and the disk-shaped movable element 4 has its one surface facing the magnet 3. Therefore, the second magnetic flux M2 generated by the magnet 3 acts as compared with the case where the mover 4 is disposed inside the inner peripheral surface 1d of the coil 1. The area (adsorption area) of the child 4 can be increased. Therefore, the attractive force F acting on the mover 4 can be made relatively large without increasing the size of the coil 1.
Furthermore, in order to make the attractive force F acting on the mover 4 relatively large, it is possible to avoid changing the material of the magnet 3 to a material having a relatively high cost and high magnetic flux density.
Further, since the magnet 3 is not fixed to the mover 4, the magnet 3 does not move even when the mover 4 moves, and is disposed at a predetermined distance from the mover 4. Thereby, the impact generated when the mover 4 moves and the mover 4 comes into contact with the outer peripheral member 2 a does not directly act on the magnet 3. Therefore, since the cracking of the magnet 3 is suppressed, the reliability of the solenoid 10 can be improved.

Further, in the solenoid 10, a flange portion 2 c 1 extending in the radial direction of the coil 1 is disposed at a predetermined distance in the radial direction of the coil 1 from the outer peripheral member 2 a of the yoke 2 at a portion where the magnet 3 of the inner peripheral portion 2 b 1 of the yoke 2 contacts. It is separated and formed over the entire circumference.
According to this, since the area where the other end surface of the inner peripheral portion 2b1 and one surface of the magnet 3 come into contact with each other can be increased by the flange portion 2c1, the second magnetic flux M2 can be further increased. Therefore, the suction force F acting on the mover 4 can be further increased.

The solenoid 10 further includes a spring 7 that presses the mover 4 toward the magnet 3, and the pressing force Fs of the spring 7 is such that when the mover 4 is located at the first position P 1, the first push of the spring 7 is performed. The magnitude of the resultant force between the pressure Fs1 and the second suction force F2 is set to be smaller than the magnitude of the predetermined external force Fg.
According to this, since the spring 7 presses the mover 4 toward the magnet 3, the mover 4 can be reliably returned from the second position P2 to the first position P1.
In addition, for example, when the solenoid 10 is used in a vehicle, the movable element 4 can be reliably held at the first position P1 even when vibration generated by traveling of the vehicle acts on the solenoid 10.

Further, in the solenoid 10, a non-magnetic shaft 5 on which a predetermined external force Fg acts is fixed to the mover 4.
According to this, since the shaft 5 on which the predetermined external force Fg acts is fixed to the mover 4, the predetermined external force Fg can be reliably applied to the mover 4.

In the above-described embodiment, an example of the solenoid is shown, but the present invention is not limited to this, and other configurations can be adopted. For example, the coil 1 and the magnet 3 may be configured such that the directions of the first magnetic flux M1 and the second magnetic flux M2 flowing in the magnetic circuit are opposite to the directions shown in FIGS. .
Further, when the mover 4 is positioned at the second position P2, the coil 1 may be energized. Further, when the mover 4 is returned from the second position P2 to the first position P1, the coil 1 may be energized. In this case, the movable element 4 moves from the second position P2 to the first position P1 by the second position attractive force Fp2 generated by at least one of the first magnetic flux M1 and the second magnetic flux M2.

  In the embodiment described above, the solenoid 10 includes the spring 7, but the spring 7 may not be included. In this case, it is preferable to set the range Ih of the current value I so that the second position attractive force Fp2 does not become zero so that the mover 4 can return from the second position P2 to the first position P1. Further, when the mover 4 is positioned above the coil 1 so that the mover 4 can return from the second position P2 to the first position P1 by its own weight. good.

  In the above-described embodiment, the shaft 5 is disposed such that the other end projects from the yoke 2 as shown in FIGS. 1 and 2, but as shown in FIG. You may make it protrude from. In this case, the bearing 6 may be disposed in the through hole 8 a of the holding member 8. Further, the length of the shaft 5 may be set so that the shaft 5 does not protrude from the outline of the solenoid 10. Further, the predetermined external force Fg may be directly applied to the mover 4 without providing the shaft 5.

  Further, in the above-described embodiment, as shown in FIGS. 1 and 2, a flange portion 2c1 is formed at the other end of the inner peripheral portion 2b1, and one surface of the magnet 3 and the end surface of the flange portion 2c1 are in contact with each other. It arrange | positions so that the one surface of the needle | mover 4 and the other end surface of the outer peripheral member 2a may be contacted. Instead, as shown in FIG. 4, the flange portion 2d1 of the flange member 2d is provided at the other end of the outer peripheral member 2a, and the diameter is extended from the inner peripheral portion 2b1 so as to protrude radially inward from the other end of the outer peripheral member 2a. It is formed over the entire circumference at a predetermined distance in the direction, and is arranged so that one surface of the magnet 3 and the end surface of the flange portion 2d1 are in contact with each other, and the one surface of the mover 4 and the other end surface of the inner peripheral portion 2b1 May be arranged so as to be in contact with each other. In this case, the magnet 3 is disposed at a predetermined distance in the radial direction from the inner peripheral portion 2b1.

In the above-described embodiment, one of the flange portion 2c1 and the flange portion 2d1 and the magnet 3 are in contact with each other, but the yoke 2 is not provided with the flange member 2c and the flange member 2d, so that the outer peripheral member 2a and the inner member 2 The other end face of the peripheral portion 2b1 and the magnet 3 may be brought into contact with each other.
In the above-described embodiment, the shaft 5 is supported via the bearing 6, but the bearing 6 may not be provided. In this case, the shaft 5 may be supported by the inner peripheral surface of the yoke 2 or the through hole 8a.

  In the above-described embodiment, the coil 1 is formed in a cylindrical shape. However, instead of this, the radial cross-sectional shape may be formed in a cylindrical shape. Moreover, although the magnet 3 and the needle | mover 4 are formed in disk shape, it is not limited to this, You may make it form in planar view planar shape. Moreover, you may form so that the outer surface of the magnet 3 and the needle | mover 4 may have a curved surface.

  DESCRIPTION OF SYMBOLS 1 ... Coil, 1a ... 1st surface, 1b ... 2nd surface, 1c ... Outer peripheral surface, 1d ... Inner peripheral surface, 2 ... Yoke, 2a ... Outer peripheral member (outer peripheral part), 2b1 ... Inner peripheral part, 2b2 ... End surface part (Connection part) 2c1 ... flange part, 3 ... magnet, 4 ... mover, 5 ... shaft, 6 ... bearing, 7 ... spring, 10 ... solenoid, F1 ... first suction force, F2 ... second suction force, Fg ... predetermined external force, Fp1 ... first position suction force, Fp2 ... second position suction force (third suction force), Fs1 ... first pressing force, Fs2 ... second pressing force, G1 ... first gap, G2 ... second Gap, G3 ... third gap, I ... current value, M1 ... first magnetic flux, M2 ... second magnetic flux, P1 ... first position, P2 ... second position.

Claims (4)

A first surface; a second surface different from the first surface; an outer peripheral surface extending from a radially outer peripheral surface; and an inner peripheral surface extending to a radially inner peripheral surface; A cylindrical coil that generates the first magnetic flux by
An outer peripheral portion extending along an outer peripheral surface of the coil, an inner peripheral portion extending along an inner peripheral surface of the coil, an end portion extending along the first surface of the coil, and one end portion of the outer peripheral portion and the inner portion A yoke that forms a magnetic circuit through which the first magnetic flux flows, and a coupling portion that couples one end of the peripheral portion;
Opposite the second surface of the coil and in contact with one of the outer peripheral portion and inner peripheral portion of the yoke and from the other of the outer peripheral portion and inner peripheral portion of the yoke in the radial direction of the coil A magnet that is disposed at a predetermined distance and generates a second magnetic flux that flows through the magnetic circuit in a direction opposite to the direction in which the first magnetic flux flows;
A magnetic mover that faces the magnet and is capable of contacting the other of the outer peripheral portion and the inner peripheral portion of the yoke and spaced from the magnet in a predetermined distance in the axial direction of the coil; A solenoid comprising
The mover is
From the first position in contact with the other of the outer peripheral portion and inner peripheral portion of the yoke and the other of the outer peripheral portion and inner peripheral portion of the yoke, in the axial direction of the coil, further than the first position Move between the distant second positions,
When the mover is positioned at the first position, the first attracting force is generated by the second magnetic flux and attracts the mover toward the magnet when the coil is not energized. Held in position,
When the coil is not energized and the mover is held in the first position by the first suction force, the direction in which the first suction force acts on the mover is opposite to When a predetermined external force smaller than the first attractive force acts on the mover by an external member, the first magnetic force is generated by energizing the coil, whereby the first attractive force is smaller than the predetermined external force. By changing to the suction force, it moves from the first position to the second position,
When the movable element is located at the second position, the predetermined external force by the external member and the third attractive force that is generated by at least the second magnetic flux and attracts the movable element toward the magnet are the movable element. A solenoid that moves from the second position to the first position when the predetermined external force is removed.   A flange portion extending in a radial direction of the coil is disposed at a portion where the magnet contacts one of the outer peripheral portion and the inner peripheral portion of the yoke, and the coil extends from the other of the outer peripheral portion and the inner peripheral portion of the yoke. The solenoid according to claim 1, wherein the solenoid is formed over the entire circumference at a predetermined distance in the radial direction. A spring that presses the mover toward the magnet;
The pressing force of the spring is set so that the magnitude of the resultant force of the pressing force of the spring and the second suction force is smaller than the magnitude of the predetermined external force when the mover is located at the first position. The solenoid according to claim 1 or 2, wherein   The solenoid according to any one of claims 1 to 3, wherein a non-magnetic shaft on which the predetermined external force acts is fixed to the mover.

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