Magnetic Adsorption Device

Abstract

To provide a magnetic sucker which is of a simple structure and is compact, yet capable of obtaining sufficient magnetic forces, and which has good rotational operability and excellent ease of use, with no flux leakage from a suction unit and opposite surface.SOLUTION: Provided is a magnetic sucker comprising a permanent magnet rotor 5 which is accommodated in an accommodation unit 2a of a device body 2, and where a pair of yokes 5b, 5c magnetized to an N or S pole centering on a rare earth magnet block 5a is rotatably supported so as to respectively face the inner surface of the accommodation unit of a magnetic housing 2b; and a handle unit 6 which is connected to a shank on one longitudinal end side of the permanent magnet rotor. The permanent magnet rotor is turned a prescribed angle by rotation operation of the handle unit so as to switch between a first position where a plurality of magnetic circuits M1, M2 are formed and a base unit 4 is attracted to a magnetic member 8 facing a suction unit 2e and a second position where a plurality of magnetic closing circuits M1', M2' separated by separators 2c, 2d between the device body and the permanent magnet rotor respectively are formed, and the base unit releases the magnetic member facing the suction unit.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a magnetic attraction device that magnetically attracts a magnetic member by a magnetic circuit formed by magnetic flux generated from a permanent magnet. [Background technology]

[0002] The magnetic attraction device comprises a device main body having a housing with a circular cross section in a magnetic housing, and a permanent magnet rotor rotatably supported in the housing. The device main body is magnetically divided into a pair of magnetic pole members by a pair of spacers provided in the magnetic housing. The permanent magnet rotor integrally comprises a permanent magnet magnetized to a north pole or south pole and a yoke. One side of the device main body has an attraction part that attracts magnetic materials such as workpieces, iron plates, and steel materials.

[0003] An example of a magnetic adsorption device is shown in Figures 15(a) and (b). A magnetic housing-like device main body 101 has a container 102 with a circular cross section provided therein. The device main body 101 is magnetically divided into two parts, a pair of magnetic pole members, by a pair of separators 103 (e.g., made of aluminum) arranged at opposing positions. One surface (bottom surface) of the device main body 101 has an adsorption part 101a that attracts magnetic materials such as workpieces, iron plates, steel materials, etc. Furthermore, the separator 103 provided on the surface portion 101b opposite to the adsorption part 101a has a tapped hole for mounting.

[0004] The permanent magnet rotator 104 is made by stacking a yoke 106 on both sides (north and south pole faces) of a plate-shaped permanent magnet 105 such as a ferrite magnet or a rare earth magnet and screwing them together. The surface of the yoke 106 facing the housing is formed into an arcuate surface. The permanent magnet rotator 104 can be rotated between a first position and a second position by a lever (not shown) that is extended to the outside of the device body 101. The rotation angle of the permanent magnet rotator 104 is designed to be in the range of 90° to 100° at the center angle.

[0005] 15(a) shows a case where the permanent magnet rotating body 104 is in the first position. Magnetic flux generated from the N-pole side yoke 106 passes through the opposing device main body 101, passes through the outside of the separator 103 provided on the attraction part 101a and the opposite surface part 101b, passes through the device main body 101, and returns to the S-pole side yoke 106, forming a magnetic circuit M. At this time, the device main body 101 is attracted and held by a magnetic body (not shown) arranged opposite the attraction part 101a.

[0006] 15(b) shows a case where the permanent magnet rotating body 104 is in the second position. A plurality of magnetic closed circuits M' are formed in which the magnetic flux generated from the N-pole side yoke 106 passes through the opposing device body 101 and returns to the S-pole side yoke 106 while facing the side surface of the permanent magnet 105 on the inside. At this time, the magnetic field lines do not leak outward from the attraction portion 101a, and the device body 101 is not attracted to the magnetic body (not shown) arranged opposite the attraction portion 101a.

[0007] The applicant has also proposed a magnetic attraction device that exerts an attractive force when the rotation angle of the permanent magnet rotor is smaller than 90° (Patent Document 1; JP 2005-19551 A). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2005-19551 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, the magnetic attraction device of the above-mentioned Patent Document 1 has a permanent magnet assembly in a circular cross-sectional cavity that penetrates the magnetic circuit block in the longitudinal direction, and a magnetic attraction surface is formed by fixing a pair of seats by welding or bolts to a mounting surface that is partially chamfered from the magnetic circuit block. The permanent magnet assembly has a pair of permanent magnets attached to the outer periphery of a cylindrical magnetic pole member, the inner surface of which is formed in an arc shape with the same curvature as the magnetic pole member. A rod-shaped handle is connected to one longitudinal end of the magnetic pole member, and can be rotated at an angle of less than 90° to switch between attraction and release in a first recess and a second recess in an end plate provided at both ends of the magnetic circuit block. As such, the magnetic attraction surface of the magnetic circuit block requires labor such as chamfering and welding of the seat, and because the permanent magnet is attached to the outer periphery of the magnetic pole member, it tends to become larger in the radial direction. In addition, a structure is required to fix the handle and its rotational position, which increases the number of parts and machining operations and increases production costs.

[0010] 15(a) and (b), when a rare earth magnet is used for the permanent magnet rotor 104, the rotation angle of the lever is 90° to 100° at the center angle, so the amount of rotation is large and requires a rotational force, resulting in poor operability. Also, since the permanent magnet 105 and the yoke 106 are stacked on both sides of the permanent magnet 105 and screwed in place, the number of parts increases, screw hole processing is required, and the magnetic force of the permanent magnet 105 is weakened. Furthermore, as shown in FIG. 15(a), when the attraction portion 101a of the device main body 101 is attracted to a magnetic member, a magnetic circuit M is formed on the opposite surface portion 101b of the attraction portion 101a, through which magnetic flux leaks to the outside. Therefore, when the opposite surface portion 101b is used as an attachment portion for instruments such as measuring devices, it is necessary to take measures against magnetism. Furthermore, since the separator 103, which is structurally weak, has tapped holes, there is a risk that its strength may be reduced. [Means for solving the problem]

[0011] The present invention has been made to solve these problems, and its object is to provide an easy-to-use magnetic attraction device that has a simple configuration, is small but provides sufficient magnetic force, has good rotational operability, and does not leak magnetic flux from the surface opposite the attraction part.

[0012] In order to achieve the above object, the present invention provides a magnetic adsorption device having the following configuration. The magnetic housing has a housing section with a circular cross section inside, and a first separator and a second separator that magnetically divide the magnetic housing are arranged on adjacent side surfaces of the magnetic housing at a predetermined angle less than 180° at the center angle to form a plurality of magnetic circuits, and an attraction section that attracts an opposing magnetic member across any of the separators is formed; a base section having a lid section that closes the opening of the housing section of the device main body; a permanent magnet rotor that is housed in the housing section of the device main body, and has a pair of yokes magnetized to N poles or S poles around a rare earth magnet block, each of which has a chamfered portion where the arc surfaces that face the inner surface of the housing section of the magnetic housing are chamfered, and is rotatably supported facing the inner surface of the housing section of the magnetic housing; and a length of the permanent magnet rotor a handle portion connected to the shaft portion at one end in the hand direction and having an operation portion attached thereto and exposed from the lid portion, and the permanent magnet rotor is rotated by a predetermined angle less than 90° about a central angle by rotating the handle portion, and is switched between a first position in which a plurality of magnetic circuits are formed so that the magnetic flux leaks from the device body to the outside of the first separator and the second separator, the base portion is attracted to the magnetic member facing the attraction portion, and the magnetic flux does not leak out of the device body from the surface portion opposite the attraction portion, and a second position in which a plurality of magnetic closed circuits separated by the first separator and the second separator are formed between the device body and the permanent magnet rotor, and the base portion releases the attraction to the magnetic member facing the attraction portion, When the handle portion is in the first position, a magnetized boundary portion of the rare earth magnet block is disposed opposite the first separator provided on the attraction portion, and any chamfered portion is disposed opposite the second separator, thereby forming a plurality of magnetic circuits that allow magnetic flux to leak outside the device body across the first separator and the second separator. It is characterized by the above.

[0013] In this way, the device body is a magnetic device in which multiple magnetic circuits are formed. Chassis A part of the device is equipped with an adhesive, and the magnetic Chassis A housing portion having a circular cross section is provided inside the housing portion. First and second magnetic strips are placed on adjacent sides of the magnetic housing. Since the magnetic pole members are magnetically divided into a plurality of magnetic pole members by the separators, the number of parts and the number of processing steps can be reduced, resulting in a simplified configuration. In addition, by using a permanent magnet rotor in which a pair of yokes magnetized to north or south poles are rotatably supported around the rare earth magnet block so that they each face the inner surface of the storage section of the magnetic block, sufficient magnetic force can be obtained even with a small diameter. By providing a handle section that is connected to the shaft section at one longitudinal end of the permanent magnet rotor and has an operating section exposed from the cover section, the permanent magnet rotor housed in the device body can be rotated within a specified angular range of less than 90°, allowing the base section to switch between attraction and release with respect to the magnetic member facing the attraction section, thereby improving rotational operability. Furthermore, by arranging the first separator and the second separator at a specified angle of less than 180°, it is possible to prevent magnetic flux from leaking outside the device body from the side opposite the suction portion of the device body, and it is possible to drill tapped holes for mounting in a structurally strong magnetic casing other than the first and second separators, thereby improving the mounting strength.

[0014] Also, When the handle portion is in the first position, a magnetic circuit is formed in which the magnetic flux generated from the N-pole yoke passes through the opposing magnetic housing, passes the outside of the first separator, passes through the magnetic housing, and returns to the S-pole yoke. At this time, the base portion can be attracted and held by the magnetic body facing the attraction portion. In addition, a magnetic circuit is formed in which the magnetic flux generated from the N-pole yoke passes through the opposing magnetic housing, passes the outside of the second separator, passes through the magnetic housing, and returns to the S-pole yoke.

[0015] When the handle portion is in the second position, it is preferable that the arcuate surfaces of the pair of yokes are each arranged opposite a first separator or a second separator provided on the magnetic housing, thereby forming a plurality of magnetic closed circuits in which magnetic flux does not leak between the magnetic housing and the permanent magnet rotating body. As a result, when the handle portion is in the second position, multiple magnetic closed circuits are formed in which the magnetic flux generated from the N-pole yoke passes through the opposing magnetic casing and returns to the S-pole magnetic block, and the base portion is not attracted to the magnetic body opposing the attraction portion.

[0016] The first separator and the second separator Each of the plates may be formed with a thin portion where the plate thickness is thin. This means: The first separator and the second separator can be processed integrally by cutting, molding or other processes when forming the storage section and the adsorption section of the magnetic casing, which reduces the number of parts and simplifies the structure.

[0017] The gap forming the thin portion may also serve as a positioning hole into which a boss of a lid portion that closes the housing portion of the magnetic casing is inserted. This makes it possible to omit the screw holes for fixing the lid to the device body, improving assembly and increasing the amount of magnetic flux passing through the magnetic casing.

[0018] The above magnetic The side surface of the housing may be formed with a curved surface that is continuous with the thin portion that forms the second separator. This allows the magnetic workpiece to magnetic Even if the magnetic workpiece is placed adjacent to the side of the housing, the curved surface provides escape space, making it possible to prevent the magnetic workpiece from being unintentionally attracted to any surface other than the attraction surface.

[0019] before A non-magnetic material may be interposed between adjacent side surfaces of the magnetic casing. In this way, by interposing a non-magnetic material (e.g., aluminum material) between adjacent side surfaces of the magnetic casing, the magnetic casing can be divided into a plurality of magnetic pole members in the same manner as the thin-walled portion. In this case, it is also possible to prevent magnetic flux from leaking out of the device body from the side portion opposite the adsorption portion of the device body, and since tapped holes for attachment can be processed in the structurally strong magnetic casing other than the separator, the attachment strength is also improved.

[0020] The handle portion connected to the permanent magnet rotor may be provided so as to be rotatable (forward and reverse rotatable) within a central angle range of 60° to 70°. This improves the ease of rotation of the handle portion by the operator even when a rare earth magnet block is used for the permanent magnet rotating body.

[0021] The base portion may be formed on one surface of the device body with an adhesive portion adapted to be attached to a magnetic member, and the surface opposite to the adhesive portion may be an attachment portion for an attachment target member. As a result, no leakage magnetic flux occurs when the device is attached to the surface opposite the suction part of the device body, which is a magnetic casing, so no special magnetic countermeasures are required when attaching the device, making it easy to use and versatile.

[0022] In another configuration, a first separator and a second separator that magnetically divide the magnetic cylinder and have a circular cross-sectional container inside the magnetic cylinder are arranged at a predetermined angle less than 180° at the center angle to form a plurality of magnetic circuits, and Consists of The magnetic cylinder is provided with a lid for closing the container opening, and an adsorption portion for adsorbing to the opposing magnetic member across any of the separators is formed at the other end of the magnetic cylinder in the longitudinal direction. Body a permanent magnet rotor that is housed in the housing of the magnetic cylindrical body and has a pair of yokes that are magnetized to N or S poles around a rare earth magnet block and are rotatably supported facing the inner surface of the housing of the magnetic cylindrical body; and a handle portion that is connected to a shaft portion on one end side of the permanent magnet rotor in the longitudinal direction and has an operation portion exposed from the lid portion and assembled thereto, the handle portion being a rotating plate that is connected to the shaft portion on one end side of the permanent magnet rotor in the longitudinal direction and that is rotatably assembled by being sandwiched between the device body and the lid portion with the outer circumferential surface exposed at one end side of the magnetic cylindrical body, and the pair of yokes each have a chamfered portion on the arcuate surface that faces the inner surface of the housing of the magnetic cylindrical body, and the pair of yokes are rotated by rotating the handle portion. The permanent magnet rotating body is rotated a predetermined angle less than 90° around a central angle, and when the handle portion is in a first position, the magnetization boundary portion of the rare earth magnet block is arranged opposite a first separator provided on the attraction portion, and any of the chamfered portions is arranged opposite a second separator, thereby forming a plurality of magnetic circuits that allow magnetic flux to leak from the attraction portion, and the base portion is attracted to the magnetic member facing the attraction portion, and when the handle portion is in a second position, the arcuate surfaces of the pair of yokes are arranged opposite a first separator or a second separator provided on the magnetic cylindrical body, respectively, thereby forming a plurality of magnetic closed circuits that do not allow magnetic flux to leak between the magnetic cylindrical body and the permanent magnet rotating body, and the base portion releases the attraction of the magnetic member facing the attraction portion. As a result, when the handle portion is in the first position, multiple magnetic circuits are formed in which the magnetic flux generated from the N-pole yoke passes through the end face of the opposing magnetic cylinder, straddles the first separator or the second separator, and returns to the S-pole yoke. At this time, the base portion can be attracted and fixed to the magnetic member facing the attraction portion. In this way, by using one longitudinal end side of the magnetic cylinder as the attraction portion and disposing the handle portion on the other longitudinal end side, it can be installed even in places where the attraction area is narrow. When the handle is in the second position, multiple magnetic closed circuits are formed in which the magnetic flux generated from the N-pole yoke passes through the opposing magnetic cylinder and returns to the S-pole yoke. At this time, the magnetic flux does not leak from the magnetic cylinder, so it is not attracted to the magnetic member facing the end face of the magnetic cylinder. In this way, the rotating plate is connected to the permanent magnet rotor and disposed at one end of the magnetic cylinder, and the cover is attached to the magnetic cylinder by overlapping the rotating plate, so that the rotating plate serving as the operating part does not require a large installation area and can be disposed compactly. Also, by arranging the cover over the handle, screw holes can be provided in the cover and it can be used as an attachment surface for equipment.

[0025] The cover portion may be disposed on the surface of the magnetic cylinder opposite the attraction portion on the other end side, and may serve as a mounting surface for a mounting member. In this case, the lid portion also serves as the mounting surface for the workpiece, so the magnetic adsorption device can be placed without taking up much installation space, and tapped holes can be provided in the relatively strong lid portion to serve as the mounting surface.

[0026] It is desirable that the permanent magnet rotating body be rotatably supported via a bearing provided on at least one end side within the housing portion of the device main body. The permanent magnet rotating body has yokes arranged on both sides of the rare earth magnet block, and the magnetic attraction force is greater than that of ferrite magnets, etc., which can easily reduce rotational operability. However, the rotational operability can be improved by inserting a bearing on at least one end. Effect of the Invention

[0027] It is possible to provide an easy-to-use magnetic attraction device which has a simple structure, is small but has sufficient magnetic force, has good rotational operability, and has no leakage of magnetic flux from the surface opposite to the attraction portion. [Brief description of the drawings]

[0028] [Figure 1] 1A and 1B are a front view, a plan view, and a sectional view taken along the arrow AA direction of a magnetic adsorption device according to a first embodiment. [Diagram 2] 2 is an explanatory diagram of a magnetic circuit formed in the device body according to the rotational position of a permanent magnet rotating body in the magnetic attraction device of FIG. 1. [Diagram 3] 2A and 2B are a front view and a plan view of a device main body used in the magnetic adsorption device of FIG. [Figure 4] 2A and 2B are a front view and a plan view of a yoke used in the magnetic adsorption device of FIG. [Diagram 5] FIG. 2 is an exploded perspective view of the magnetic adsorption device of FIG. [Figure 6] 11A is a front view, a plan view, and a sectional view taken along the arrow BB of a magnetic adsorption device according to a second embodiment of the present invention. [Figure 7] 7A and 7B are a front view and a plan view of a device main body used in the magnetic adsorption device of FIG. 6. [Figure 8] 7A and 7B are a front view and a plan view of a yoke used in the magnetic adsorption device of FIG. 6. [Figure 9] FIG. 7 is an exploded perspective view of the magnetic adsorption device of FIG. 6. [Figure 10] FIG. 11 is an explanatory diagram showing a modified example of the device main body used in the first and second embodiments. [Figure 11] 13 is an explanatory diagram of a magnetic circuit formed in a device body according to a rotational position of a permanent magnet rotating body used in a magnetic attraction device according to a third embodiment. FIG. [Figure 12] 13A and 13B are a perspective view and an exploded perspective view of a magnetic adsorption device according to a fourth embodiment. [Figure 13] 13A and 13B are a front view, a plan view and a rear view of a device main body used in the magnetic adsorption device of FIG. 12, a front view and a plan view of a handle portion, and a front view and a plan view of a cover body. [Figure 14]13 is a front view, a bottom view and a horizontal sectional view of the magnetic attraction device of FIG. 12, illustrating a magnetic circuit formed in the device body according to the rotational position of a permanent magnet rotating body. [Figure 15] 1 is an explanatory diagram of a magnetic circuit formed in a device body according to the rotational position of a permanent magnet rotating body of a current magnetic attraction device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] [Example 1] Hereinafter, a schematic configuration of the magnetic attraction device according to the first embodiment will be described with reference to Fig. 1 to Fig. 5. In Fig. 1(a) to (c), the magnetic attraction device 1 includes a device main body 2 having a storage section 2a with a circular cross section inside a magnetic housing 2b (magnetic block), a base section 4 having a lid section 3 that closes the opening of the storage section 2a of the device main body 2, a permanent magnet rotating body 5 in which a pair of yokes magnetized to N poles or S poles are provided around a rare earth magnet block 5a so as to face the inner surface of the storage section of the device main body, and a handle section 6 connected to a shaft section on one end side in the longitudinal direction of the permanent magnet rotating body 5 and having a lever 6a (operating section) extended on the outer surface of the lid section 3.

[0030] The configuration of each part will be described below. As shown in Fig. 2(a)(b), the device main body 2 uses a magnetic housing 2b made of, for example, iron. The magnetic housing 2b is divided into a plurality of magnetic pole members by a plurality of separators (first separator 2c, second separator 2d) to form a plurality of magnetic circuits. The device main body 2 is formed with an adsorption part 2e that straddles the first separator 2c and is attracted to the opposing magnetic member 8 (see Fig. 2(a)). The adsorption part 2e is formed on a flat surface that is continuous with inclined surfaces that are chamfered in a V-shape on both sides, sandwiching the thin first separator 2c adjacent to the storage part 2a.

[0031] As shown in FIG. 3(b), the first separator 2c and the second separator 2d are formed by thin-walled portions where the plate thickness of the adjacent side surfaces of the magnetic housing 2b constituting the device main body 2 is thin. The first separator 2c and the second separator 2d are formed by forming gaps such as round holes and recesses on the adjacent side surfaces of the magnetic housing 2b. In this case, when the storage section 2a and the adsorption section 2e of the device main body 2 are formed by cutting or molding, the first separator 2c and the second separator 2d can be processed integrally, and the number of parts can be reduced to make a simple structure. In addition, as described later, by setting the arrangement of the first separator 2c and the second separator 2d at a predetermined angle less than 180° (for example, a central angle in the range of 145° to 150°), it is possible to prevent magnetic flux from leaking from the side portion (attachment section 2f) opposite the adsorption section 2e of the device main body 2. Also, a screw hole 2g (tapped hole) is drilled in the mounting portion 2f, which is the surface opposite to the suction portion 2e. For example, when a holder for holding a dial gauge or the like is attached to the mounting portion 2f, the shaft of the holder can be screwed into the screw hole 2g to attach it. Note that if another attachment method is used, the screw hole 2g may be omitted. In this way, tapped holes for attachment can be drilled in the structurally strong magnetic housing 2b other than the separator in the device main body 2, and the attachment strength is also improved.

[0032] 3(b), boss holes 2h and 2i are provided around the housing portion 2a. Bosses 3a and 3b provided on the lid portion 3, which will be described later, are fitted into the boss holes 2h and 2i, respectively. As shown in FIG. 3(a), the boss hole 2h is formed continuously with the accommodating portion 2a, and is formed from the front side of the magnetic casing 2b along the longitudinal direction to near the rear side in order to form the second separator 2d.

[0033] 2(a) and 2(b), the permanent magnet rotating body 5 is rotatably supported by a pair of yokes 5b, 5c magnetized to the N pole or S pole around a plate-shaped rare earth magnet block 5a, with a small gap between them and the inner surface of the housing section 2a of the device main body 2. The polarities of the N pole side yoke 5c and the S pole side yoke 5b may be interchanged. 4(a)(b), the permanent magnet rotor 5 is magnetically divided into left and right semi-cylindrical blocks by forming an insertion hole 5d in the radial direction intersecting with the longitudinal center axis of the cylindrical block made of a magnetic material (the pair of yokes 5b, 5c are mechanically connected together by bearing mounting parts 5e, 5f provided at both longitudinal ends). In addition, the radial end side (upper end side in FIG. 4(a)) of the semi-cylindrical blocks of the pair of yokes 5b, 5c is respectively formed with chamfered parts 5b1, 5c1 with chamfered arc surfaces. The plate-shaped rare earth magnet block 5a is inserted into the insertion hole 5d of this cylindrical block and magnetized to the N pole or S pole, and the pair of yokes 5b, 5c are formed with the N pole side yoke 5c and the S pole side yoke 5b facing the inner surface of the housing part 2a of the device main body 2 in plane symmetry (see FIG. 2(a)(b)).

[0034] 4(b), small-diameter cylindrical bearing attachment parts 5e and 5f are provided at both longitudinal ends of the pair of yokes 5b and 5c. Rolling bearings 7a and 7b are fitted into the outer peripheries of the bearing attachment parts 5e and 5f, respectively, as described below. As shown in FIG. 4(a), the bearing mounting portion 5e on one side (front side) is provided with a fitting hole 5g that fits with a fitting protrusion 6b of the handle portion 6, which will be described later.

[0035] 5, rolling bearings 7a, 7b (bearings) are mounted on the outer periphery of bearing mounting parts 5e, 5f provided at the longitudinal ends of a pair of yokes 5b, 5c, respectively. As shown in FIG. 1(c), the rolling bearings 7a, 7b are fitted into the housing part 2a of the device body 2 together with the pair of yokes 5b, 5c, and support the permanent magnet rotating body 5 rotatably relative to the device body 2. In this way, by supporting the permanent magnet rotating body 5 via the rolling bearings 7a and 7b, it is possible to improve the rotational operability of the permanent magnet rotating body 5 using the rare earth magnet block 5a. As will be described later, it is also possible to omit one of the pair of rolling bearings 7a and 7b by changing the shape of the bearing mounting portion.

[0036] In FIG. 5, the handle portion 6 has a lever 6a that is held by an operator and extends radially from the front side, and a fitting protrusion 6b that protrudes from the rear side. The fitting protrusion 6b is assembled so as to fit into a fitting hole 5g of the opposing bearing mounting portion 5e. An arc-shaped protrusion 6c is provided on the outer circumferential edge of the handle portion 6, and is fitted rotatably within a predetermined range along a notched recess 3d provided in the circumferential direction on the inner wall surface of a fitting cylinder portion 3c provided on the rear side of the cover portion 3, which will be described later. That is, the handle portion 6 is assembled so that the arc-shaped protrusion 6c rotates within the range of the notched recess 3d provided in the circumferential direction (central angle θ: range of 60° to 70°).

[0037] A hole 3e is provided in the center of the lid 3, and the lid 3 is attached from the front side of the handle 6, with the lever 6a exposed outside the hole 3e of the lid 3, as shown in Figures 1(a) and 1(b). In addition, bosses 3a and 3b provided at diagonal positions on the rear side of the lid 3 are fitted into boss holes 2h and 2i provided around the housing 2a of the device body 2 for assembly. In this way, the boss hole 2h forming the second separator 2d also serves as a positioning hole into which the boss portion 3a of the lid portion 3 that closes the storage section 2a of the magnetic casing 2b is inserted, thereby making it possible to omit a screw hole for fixing the lid portion 3 to the device main body 2, improving assembly ease and increasing the amount of magnetic flux passing through the magnetic casing 2b.

[0038] In this embodiment, as shown in Fig. 1(a), the handle portion 6 connected to the permanent magnet rotator 5 is provided so as to be rotatable within a range of 60° to 70° when the lever 6a has a central angle θ. This improves the ease of rotation of the handle portion 6 by an operator. When an operator holds the lever 6a and rotates the handle portion 6 to a first position shown by a solid line in Fig. 1(a), the magnetized boundary portion (end face) of the rare earth magnet block 5a is disposed opposite the first separator 2c in Fig. 2(a), and the chamfered portion 5b1 of the yoke 5b is disposed opposite the second separator 2d provided on the device main body 2. At this time, a first magnetic circuit M1 is formed in which magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, across the first separator 2c, and from the attraction part 2e to the outside of the device body 2, and returns to the S-pole side yoke 5b through the magnetic casing 2b, and a second magnetic circuit M2 is formed in which magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, across the second separator 2d, and returns to the S-pole side yoke 5b through the magnetic casing 2b. The first magnetic circuit M1 is formed in the magnetic member 8 disposed opposite the attraction part 2e, and the base part 4 is attracted and held by the magnetic member 8.

[0039] Furthermore, when the operator rotates the handle portion 6 via the lever 6a to the second position shown by the dashed line in FIG. 1(b), in FIG. 2(b), the arcuate surface of the N-pole side yoke 5c is positioned opposite the first separator 2c, and the arcuate surface of the S-pole side yoke 5b is positioned opposite the second separator 2d. At this time, a first magnetic closed circuit M1' is formed, which runs from the N-pole side yoke 5c through the opposing magnetic casing 2b and returns to the S-pole side yoke 5b while looking inward at the chamfered portions 5c1, 5b1, and a second magnetic closed circuit M2' is formed, which runs from the N-pole side yoke 5c through the opposing magnetic casing 2b and returns to the S-pole side yoke 5b while looking inward at the magnetized boundary portion (end face) of the rare earth magnet block 5a. As a result, when the handle portion 6 is in the second position, no magnetic flux is generated that leaks out of the device body 2 from the attraction portion 2e, and therefore the base portion 4 is not attracted to the opposing magnetic member 8.

[0040] As shown in FIG. 5, to assemble the magnetic adsorption device 1, a plate-shaped rare earth magnet block 5a is inserted into an insertion hole 5d between the yokes 5b and 5c with chamfered portions 5b1 and 5c1 to prepare a permanent magnet rotor 5 magnetized to the N pole or S pole. This permanent magnet rotor 5 is prepared. Rolling bearings 8a and 8b are fitted into the bearing mounting portions 5e and 5f extended at both ends in the longitudinal direction, and these are inserted into the housing portion 2a of the device body 2 for assembly. The fitting protrusion 6b of the handle portion 6 is fitted into the fitting hole 5g of the bearing mounting portion 5e to be assembled together. Finally, the lever 6a is inserted through the hole 3e of the cover portion 3 and exposed to the outside, and the boss portions 3a and 3b are fitted into the boss holes 2h and 2i of the device body 2 to assemble it. In this way, by minimizing the use of screws in assembling the parts together, the ease of assembly is improved and magnetic loss is prevented.

[0041] As described above, when the handle portion 6 is in the first position, a first magnetic circuit M1 is formed in which the magnetic flux generated from the N-pole side yoke 5c passes through the opposing device main body 2, passes outside the first separator 2c, and returns to the S-pole side yoke 5b via the device main body 2, and the base portion 4 can be attracted to the magnetic member 8 facing the attraction portion 2e. Also, a second magnetic circuit M2 is formed in which the magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, straddles the second separator 2d, and returns to the S-pole side yoke 5b through the magnetic casing 2b, but since there is no magnetic flux leakage from the mounting portion 2f, which is the surface opposite to the attraction portion 2e, no special magnetic countermeasures are required when mounting a measuring device, etc., and the device is easy to use and has a wide versatility. The permanent magnet rotor 5 has a pair of yokes 5b, 5c arranged on either side of the rare earth magnet block 5a, and although its magnetic attraction is greater than that of ferrite magnets and the like, and rotational operability is easily reduced, the use of rolling bearings 7a, 7b improves rotational operability. In addition, the rotational angle of the lever 6a is also good because the central angle θ is in the range of 60° to 70°.

[0042] [Example 2] A schematic configuration of a magnetic attraction device according to a second embodiment will be described below with reference to Fig. 6 to Fig. 9. The same members as those in the first embodiment are given the same reference numbers and the description will be repeated. The following description will focus on the different configurations. 6(a) to (c), the magnetic adsorption device 1 includes a device body 2 having a container 2a with a circular cross section inside a magnetic housing 2b, a base 4 having a lid 3 for closing the opening of the container 2a of the device body 2, a permanent magnet rotor 5 supported rotatably such that a pair of yokes 5b, 5c magnetized to N poles or S poles around a rare earth magnet block 5a face the inner surface of the container 2a of the device body 2, and a handle 6 connected to a shaft on one end of the permanent magnet rotor 5 in the longitudinal direction and having a lever 6a extending from the outer surface of the lid 3, which is the same as in the first embodiment. In this embodiment, the rolling bearing 7b of the pair of bearings is omitted from the first embodiment, and the structures of the permanent magnet rotor 5 and the device body 2 supporting it rotatably are different.

[0043] As shown in FIG. 6(c), the permanent magnet rotating body 5 has a pair of yokes 5b, 5c formed in a plane symmetry, the pair having chamfered portions 5b1, 5c1 whose arcuate surfaces are chamfered and magnetized to the N pole or the S pole while the plate-shaped rare earth magnet block 5a is inserted into the insertion hole 5d of the cylindrical block, and the pair of yokes 5b, 5c are formed in a plane symmetry, similar to the first embodiment.

[0044] 8(a) and 8(b), a small-diameter cylindrical bearing attachment portion 5e is extended from one longitudinal end of the cylindrical block constituting the yoke 5b, 5c. A rolling bearing 7a is fitted to the outer periphery of the bearing attachment portion 5e, as described later. A conical shaft portion 5h having a tapered surface protrudes from the center of the other longitudinal end of the cylindrical block constituting the yoke 5b, 5c. The tip of the conical shaft portion 5h does not have to be sharply pointed, and may be chamfered into a truncated cone shape.

[0045] As shown in FIG. 7(a), the device body 2 uses a magnetic casing 2b made of, for example, iron. The magnetic casing 2b is divided into a plurality of magnetic pole members by a first separator 2c and a second separator 2d to form a plurality of magnetic circuits. The device body 2 is formed with an adsorption portion 2e that straddles the first separator 2c and adsorbs an opposing magnetic body (not shown). The first separator 2c and the second separator 2d are formed by thin-walled portions where the plate thickness of adjacent side surfaces of the magnetic casing 2b constituting the device body 2 is thin. The first separator 2c and the second separator 2d are also arranged at a predetermined angle of less than 180° (for example, a central angle in the range of 145° to 150°) as in the first embodiment.

[0046] As shown by the dashed lines in FIG. 7(b), boss holes 2h and 2i are provided around the periphery of the housing 2a. The bosses 3a and 3b provided on the cover 3 are fitted into the boss holes 2h and 2i, respectively, for assembly. A bearing recess 2j is provided in the center of the rear inner wall of the housing 2a. The bearing recess 2j is formed as an inverted conical hole to receive the conical shaft 5h of the permanent magnet rotor 5. As shown in FIG. 6(c), the permanent magnet rotor 5 is centered and accommodated in the housing 2a of the device body 2 by fitting the conical shaft 5h into the bearing recess 2j at the rear side in the longitudinal direction, and is rotatably supported via a rolling bearing 7a at the front side in the longitudinal direction.

[0047] As shown in FIG. 9, to assemble the magnetic attraction device 1, a plate-shaped rare earth magnet block 5a is inserted into an insertion hole 5d between the yokes 5b and 5c with chamfered portions 5b1 and 5c1 to prepare a permanent magnet rotor 5 magnetized to the N pole or S pole. A rolling bearing 7a is fitted into a bearing mounting portion 5e extended from one end of the permanent magnet rotor 5 in the longitudinal direction, and the permanent magnet rotor 5 is inserted into the accommodation portion 2a of the device body 2 from the conical shaft portion 5h side and fitted into the bearing recess 2j to assemble. The fitting protrusion 6b of the handle portion 6 is fitted into the fitting hole 5g of the bearing mounting portion 5e to assemble the device. Finally, the lever 6a is inserted through the hole 3e of the cover portion 3 and exposed to the outer surface, and the boss portions 3a and 3b are fitted into the boss holes 2h and 2i of the device body 2 to assemble the device.

[0048] Here, a modified example of the device body used in the first and second embodiments will be described with reference to FIG. 10. As shown in FIG. 2(a) described above, when the handle portion 6 is in the first position, a first magnetic circuit M1 is formed in which the magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, straddling the first separator 2c, and from the attraction portion 2e to the outside of the device body 2, and returns to the S-pole side yoke 5b through the magnetic casing 2b, and a second magnetic circuit M2 is formed in which the magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, straddling the second separator 2d, and returns to the S-pole side yoke 5b through the magnetic casing 2b. At this time, when a magnetic workpiece W is placed on the side surface 2k adjacent to the attraction surface 2e of the magnetic casing 2b, it is also assumed that the workpiece W forms the second magnetic circuit M2 and is attracted to the side surface 2k. To avoid this, a curved surface 2m is formed on the side surface 2k of the magnetic casing 2b, continuing from the thin-walled portion forming the second separator 2d. As a result, even if a magnetic workpiece W is placed adjacent to the side surface 2k, the curved surface 2m provides an escape space, thereby preventing the magnetic workpiece W from being unintentionally attracted to any surface other than the attraction surface 2e.

[0049] [Example 3] Hereinafter, a schematic configuration of a magnetic adsorption device according to Example 3 will be described with reference to Figures 11(a) and 11(b). The same members as those in Example 1 are given the same numbers and the explanations are incorporated herein, and the following description will focus on the different configurations.

[0050] The first separator 2c and the second separator 2d that magnetically divide the device body 2 are arranged at a predetermined angle smaller than 180° (for example, in the range of 145° to 150°) as in the first embodiment, but instead of the thin-walled parts, non-magnetic material (aluminum material, etc.) may be interposed between adjacent side surfaces of the magnetic casing 2b. The non-magnetic material is integrally assembled to the magnetic casing 2b by welding or bonding. In this way, by interposing a non-magnetic material (for example, aluminum material) between adjacent side surfaces of the magnetic casing 2b, the magnetic casing 2b can be divided into multiple magnetic pole members in the same manner as the thin-walled portion. In addition, since tapped holes for attachment can be processed in the structurally strong magnetic casing 2b other than the separator in the device main body 2, the attachment strength is also improved. The configuration of the permanent magnet rotating body 5 is the same as in Example 1, and the rotation angle of the handle portion 6 connected to the permanent magnet rotating body 5 is also the same in that the central angle θ is rotatable within a range of 60° to 70°.

[0051] When the operator rotates the handle portion 6 to the first position shown by the solid line in Figure 1(a), the magnetization boundary portion (end face) of the rare earth magnet block 5a is positioned opposite the first separator 2c in Figure 11(a), and the chamfered portion 5b1 of the S-pole side yoke 5b is positioned opposite the second separator 2d provided on the device main body 2. At this time, a first magnetic circuit M1 is formed in which the magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, straddles the first separator 2c, and leaks out of the device body 2 from the attraction part 2e, and returns to the S-pole side yoke 5b through the magnetic casing 2b, and a second magnetic circuit M2 is formed in which the magnetic flux leaks from the N-pole side yoke 5c through the opposing magnetic casing 2b, straddles the second separator 2d, and returns to the S-pole side yoke 5b through the magnetic casing 2b. When a magnetic body (not shown) is placed opposite the attraction part 2e, the first magnetic circuit M1 is formed and the magnetic casing 2b (base part 4) is attracted and held by the magnetic body.

[0052] Furthermore, when the operator rotates the handle portion 6 via the lever 6a to the second position shown by the dashed line in FIG. 1(b), in FIG. 11(b), the arcuate surface of the N-pole side yoke 5c is positioned opposite the first separator 2c, and the arcuate surface of the S-pole side yoke 5b is positioned opposite the second separator 2d. At this time, a first magnetic closed circuit M1' is formed which passes from the N-pole side yoke 5c through the opposing magnetic casing 2b and returns to the S-pole side yoke 5b while looking inward at the chamfered portions 5c1, 5b1, and a second magnetic closed circuit M2' is formed which passes from the N-pole side yoke 5c through the opposing magnetic casing 2b and returns to the S-pole side yoke 5b while looking inward at the magnetization boundary portion (end face) of the rare earth magnet block 5a. As a result, when the handle portion 6 is in the second position, no magnetic flux is generated that leaks out of the device main body 2 from the attraction portion 2e, and therefore the magnetic casing 2b (base portion 4) is not attracted to the opposing magnetic body (not shown).

[0053] Hereinafter, the schematic configuration of the magnetic attraction device according to the fourth embodiment will be described with reference to Figs. 12 to 14. The same members as those in the first embodiment will be assigned the same numbers and the description will be incorporated, and the following description will focus on the different configurations. The permanent magnet rotating body 5 has the same configuration as that of the first embodiment. As shown in Fig. 12(a), a magnetic cylinder 2n is used as a magnetic block, and one end of the magnetic cylinder 2n in the longitudinal direction is closed by a lid 3 via a handle 6, and an attraction part 2e is formed on the other end in the longitudinal direction, so that the magnetic block is elongated. A screw hole 3f (tap hole) is drilled in the center of the lid 3, and a holder for holding a dial gauge or the like is attached. That is, the lid 3 serves as a mounting surface for mounting the shaft of a holder (not shown) by screwing it into the screw hole 3f.

[0054] As shown in Fig. 13(b), the magnetic cylindrical body 2n has a housing portion 2a formed of a cylindrical hole extending in the longitudinal direction at the center. The permanent magnet rotating body 5 is rotatably housed in the housing portion 2a. One longitudinal end face of the magnetic cylindrical body 2a has three screw holes 2p, into which the cover portion 3 described later is screwed and assembled. The magnetic cylinder 2n is divided into a plurality of magnetic pole members by separators (first separator 2c, second separator 2d) provided at a plurality of positions in the circumferential direction. The first separator 2c and the second separator 2d are formed by a thin-walled portion where the plate thickness of the peripheral wall of the magnetic cylinder 2n constituting the device main body 2 is thin. The first separator 2c and the second separator 2d are arranged at a predetermined angle less than 180° (for example, 120° at the center angle). The first separator 2c and the second separator 2d are formed from one end side of the magnetic cylinder 2n in the longitudinal direction to the vicinity of the other end in the longitudinal direction. The first separator 2c and the second separator 2d are formed by forming a gap portion 2q such as a round hole or a recess adjacent to the storage portion 2a of the magnetic cylinder 2n. When forming the storage section 2a of the device main body 2 by cutting or molding, the first separator 2c and the second separator 2d can be machined as a single unit, and the number of parts can be reduced to make the structure simple. The gap 2q provided in the longitudinal direction of the magnetic cylinder 2n is not formed to penetrate to the annular end face that becomes the adsorption section 2e. Instead of the thin-walled section, a non-magnetic material (such as aluminum) may be interposed on the peripheral wall of the magnetic cylinder 2n. The non-magnetic material is integrally assembled to the magnetic cylinder 2n by welding or bonding.

[0055] As shown in FIG. 13(b), the handle portion 6 is a disk-shaped rotating plate. A fitting protrusion 6b is protruding from the center of the handle portion 6, which fits into a fitting hole 5g of the bearing mounting portion 5e of the yoke 5b, 5c. A fitting recess 6e is formed on the opposite surface of the fitting protrusion 6b, into which a central axis 3g of the lid portion 3, which will be described later, fits. In addition, a series of elongated holes 6d are provided in a plurality of locations (for example, three locations) on the outer periphery of the handle portion 6. The boss portion 3h is inserted into the elongated hole 6d when the lid portion 3, which will be described later, is screwed into the screw hole 2p of the magnetic cylinder 2n (see FIG. 12(b)). As shown in FIG. 13(a), the handle portion 6 is sandwiched between the device body 2 and the lid portion 3 and assembled so that the outer periphery surface 6f is exposed. Therefore, the amount of rotation of the handle portion 6 is within a range in which the boss portion 3h inserted into the elongated hole 6d and both ends of the elongated hole 6d are engaged. In addition, the outer peripheral surface 6f (operating portion) of the handle portion 6 is knurled so that an operator can grip the outer peripheral surface 6f without slipping and rotate it in a predetermined direction. By rotating the handle portion 6, the attraction portion 2e of the magnetic cylinder 2n (described later) can be switched between attraction and release.

[0056] As shown in FIG. 12(a), the cover 3 is disposed on the end surface of the magnetic cylinder 2n opposite to the attraction portion 2e, and is overlapped with the handle portion 6 (rotating plate) and connected to the end of the magnetic cylinder 2n. As shown in FIG. 13(c), the cover 3 is formed in a disk shape, and a central axis 3g that serves as the rotation axis of the handle portion 6 is protruded from the center. A screw hole 3f (tapped hole) is provided on the surface opposite the central axis 3g. In addition, boss portions 3h are provided at multiple locations (for example, three locations) on the outer periphery of the cover 3. A sleeve hole 3i is provided in the boss portion 3h, and a screw 9, which will be described later, is fitted into the boss portion 3h. In this way, the cover 3 also serves as the mounting surface of the mounting member, so that the magnetic attraction device 1 can be disposed without taking up a large installation area, and the cover 3, which has the relatively strong central axis 3g, can be provided with a tapped hole to serve as the mounting surface.

[0057] As shown in Fig. 12(b), to assemble the magnetic attraction device 1, a plate-shaped rare earth magnet block 5a is inserted into the insertion hole 5d between the yokes 5b and 5c with the chamfered portions 5b1 and 5c1 to prepare a permanent magnet rotor 5 magnetized to the N or S pole. Rolling bearings 7a and 7b are fitted into the bearing mounting portions 5e and 5f extended from both longitudinal ends of the permanent magnet rotor 5, respectively, and the permanent magnet rotor 5 is inserted into the accommodation portion 2a of the magnetic cylindrical body 2n for assembly. In addition, the handle portion 6 is overlapped on the end of the magnetic cylindrical body 2n by fitting the fitting hole 5g of the bearing mounting portion 5e into the fitting protrusion 6b of the handle portion 6 (see Fig. 13(b)). The cover 3 is fitted to the handle 6 by fitting the central axis 3g into the fitting recess 6e, and the three bosses 3h are inserted into the corresponding long holes 6d to overlap each other, and the sleeve holes 3i of each boss 3h are aligned with the corresponding screw holes 2p of the magnetic cylinder 2n and butted against each other. Then, the handle 6 and the cover 3 are assembled to the end of the magnetic cylinder 2n by fitting the screws 9 into the sleeve holes 3i and screwing them into the screw holes 2p as shown in FIG. 12(a). The outer peripheral surface 6f (operation part) of the handle 6 is assembled so as to be exposed and protrude outward from the outer peripheral surface of the cover 3. When the handle 6 is rotated, the permanent magnet rotor 5 rotates together with the handle 6, and the magnetic circuit formed in the device main body 2 is switched.

[0058] As shown in Figs. 14(a) to (c), when the handle portion 6 is in the first position (the boss portion 3h is engaged with one end of the corresponding long hole 6d), for example, as shown in Fig. 14(c), the magnetization boundary portion (end face) of the rare earth magnet block 5a is disposed facing the first separator 2c, and the chamfered portion 5b1 of the yoke 5b is disposed facing the second separator 2d provided on the device body 2. At this time, as shown in Figs. 14(a) and 14(b), the magnetic flux generated from the N-pole side yoke 5b leaks out of the device body 2 from the opposing magnetic cylindrical body 2n, and first and second magnetic circuits M1 and M2 are formed in the attraction portion 2e, which straddle the first and second separators 2c and 2d, respectively, and return to the S-pole side yoke 5c through the other magnetic cylindrical body 2n that is magnetically separated. At this time, the device body 2 is attracted and fixed to the magnetic member 8 by the magnetic flux passing through the magnetic member 8 facing the attraction portion 2e of the magnetic cylindrical body 2n. Although magnetic flux that crosses the first and second separators 2c and 2d also leaks from the outer circumferential surface of the magnetic cylindrical body 2n, this does not contribute to the attraction operation to the magnetic member 8.

[0059] As shown in Fig. 14(d) and (e), when the handle portion 6 is in the second position (the boss portion 3h is engaged with the other end of the corresponding long hole 6d), for example, the S pole of the rare earth magnet block 5a is arranged to face the first separator 2c, and the N pole is arranged to face the second separator 2d. At this time, the magnetic flux generated from the N pole side yoke 5b passes through the opposing magnetic cylindrical body 2n and returns to the S pole side yoke, forming first and second magnetic closed circuits M1' and M2' (see Fig. 14(e)). At this time, since the magnetic flux does not leak to the outside from the attraction portion 2e of the magnetic cylindrical body 2n, the attraction between the attraction portion 2e and the opposing magnetic member 8 is released. The polarities (N pole and S pole) of the rare earth magnet block 5a may be reversed.

[0060] The device main body 2 used in the above-mentioned Examples 1 to 3 has been described as being a magnetic housing 2b, but the shape of the six faces does not necessarily have to be flat, and in addition to the inclined surface formed on the adsorption part 2e, other side faces may also have uneven surfaces, inclined surfaces, curved surfaces, etc. Also, the annular shape of the magnetic cylindrical body 2n used in Example 4 does not necessarily have to be a perfect circle, and may be formed in various shapes such as an ellipse, an oval, a rectangle including a curved surface, etc. In addition, the rare earth magnet block 5a is formed in a plate shape and inserted into the insertion hole 5d provided in the radial direction, but is not limited to a plate shape, and may be formed, for example, in a column shape and inserted into an insertion hole provided in the axial direction with respect to the yoke. Further, in the above-described magnetic attraction device 1, the components are assembled by fitting together as much as possible, but they may be assembled by using press-fitting, adhesion, or the like in combination. In addition, the operating angle (rotation angle) of the handle portion 6 is exemplified as a central angle of 60° to 70°, but is not limited to this, and by adjusting the arrangement angle of the first separator 2c and the second separator 2d, it is possible to make the central angle smaller, for example, to 45° to 55°, or larger, for example, to 80° to 90°. [Explanation of symbols]

[0061] 1 Magnetic adsorption device 2 Device body 2a Storage section 2b Magnetic housing 2c First separator 2d Second separator 2e Adsorption section 2f Mounting section 2g Screw hole 2h, 2i Boss hole 2j Bearing recess 2k Side surface 2m Curved surface 2p Screw hole 2q Cavity section 3 Lid section 3a, 3b Boss section 3c Fitting tube section 3d Notched recess 3e Drill hole 3f Screw hole 4 Base section 5 Permanent magnet rotor 5a Rare earth magnet block 5b, 5c Yoke 5b1, 5c1 Chamfered section 5d Insertion hole 5e, 5f Bearing mounting section 5g Fitting hole 5h Conical shaft section 6 Handle section 6a Lever 6b Fitting convex section 6c Arc-shaped convex section 6d Long hole 6e Fitting recess 6f Outer circumferential surface 7a, 7b Rolling bearing 8 Magnetic member M1 First magnetic circuit M2 Second magnetic circuit M1' First magnetic closed circuit M2' Second magnetic closed circuit

Claims

1. a device main body having a storage section with a circular cross section inside the magnetic housing, a first separator and a second separator that magnetically divide the magnetic housing are arranged on adjacent side surfaces of the magnetic housing at a predetermined angle less than 180° at the central angle to form a plurality of magnetic circuits, and an attraction section that attracts an opposing magnetic member across any of the separators is formed, and a base section having a lid section that closes an opening of the storage section of the device main body; a pair of yokes magnetized to N or S poles around a rare earth magnet block, each of which has a chamfered arc surface facing the inner surface of the housing, the pair of permanent magnet rotors being rotatably supported facing the inner surface of the housing; a handle portion connected to a shaft portion at one end of the permanent magnet rotor in the longitudinal direction and having an operation portion exposed from the lid portion; a magnetic attraction device in which, by rotating the handle portion, a plurality of magnetic circuits are formed that cause magnetic flux to leak from the device main body to the outside of the first separator and the second separator, the base portion is attracted to a magnetic member facing the attraction portion, and magnetic flux does not leak from the surface portion opposite the attraction portion to the outside of the device main body, and a plurality of magnetic closed circuits separated by the first separator and the second separator are formed between the device main body and the permanent magnet rotor, and the base portion releases the attraction to the magnetic member facing the attraction portion, when the handle portion is in the first position, a magnetized boundary portion of the rare earth magnet block is positioned opposite the first separator provided on the attraction portion, and any chamfered portion is positioned opposite the second separator, and a plurality of magnetic circuits are formed that cause magnetic flux to leak across the first separator and the second separator to the outside of the device main body.

2. 2. The magnetic adsorption device according to claim 1, wherein, when the handle portion is in the second position, the arcuate surfaces of the pair of yokes are disposed opposite a first separator or a second separator provided on the magnetic housing, thereby forming a plurality of magnetic closed circuits in which no magnetic flux leaks between the magnetic housing and the permanent magnet rotating body.

3. 3. The magnetic adsorption device according to claim 1, wherein a first separator and a second separator which magnetically divide the magnetic casing are arranged at a predetermined angle less than 180° at a central angle, and a thin-walled portion having a thin plate thickness is formed on adjacent side surfaces of the magnetic casing.

4. 4. The magnetic adsorption device according to claim 3, wherein the gap forming said thin portion also serves as a positioning hole into which a boss of a lid for closing an opening of said housing portion of said device body is inserted.

5. 5. The magnetic adsorption device according to claim 3, wherein a curved surface is formed on the side surface of the magnetic housing, the curved surface being continuous with the thin wall portion that forms the second separator.

6. 3. A magnetic adsorption device according to claim 1, wherein a first separator and a second separator that magnetically divide the magnetic casing are arranged at a predetermined angle smaller than 180° at the central angle, and non-magnetic material is interposed between adjacent side surfaces of the magnetic casing.

7. 7. The magnetic attraction device according to claim 1, wherein the handle portion connected to the permanent magnet rotor is provided so as to be rotatable within a central angle range of 60° to 70°.

8. 8. The magnetic attraction device according to claim 1, wherein the base portion has an attraction portion formed on one surface of the device body for attraction to a magnetic member, and the surface opposite the attraction portion serves as a mounting surface for a support member.

9. a base portion having a device main body, the device main body including a first separator and a second separator having a circular cross section inside a magnetic cylinder, the first separator and the second separator magnetically dividing the magnetic cylinder being arranged at a predetermined angle less than 180° at the central angle to form a plurality of magnetic circuits, a lid portion for closing the opening of the storage portion being provided at one longitudinal end of the magnetic cylinder, and an adsorption portion for adsorbing an opposing magnetic member across any of the separators being formed at the other longitudinal end of the magnetic cylinder; a permanent magnet rotor housed in the housing of the magnetic cylinder, the rotor being rotatably supported by a pair of yokes magnetized to N or S poles around a rare earth magnet block and facing the inner surface of the housing of the magnetic cylinder; a handle portion connected to a shaft portion at one end of the permanent magnet rotor in the longitudinal direction and having an operation portion exposed from the lid portion; the handle portion is a rotating plate connected to a shaft portion at one end in the longitudinal direction of the permanent magnet rotating body, and has an outer circumferential surface exposed at one end of the magnetic cylindrical body, and is rotatably assembled by being sandwiched between the device body and the lid portion, a chamfered portion formed by chamfering an arcuate surface of each of the pair of yokes that faces the inner surface of the accommodating portion of the magnetic cylindrical body; and a magnetic attraction device in which the permanent magnet rotor is rotated by a predetermined angle less than 90° around a central angle by rotating the handle portion, so that when the handle portion is in a first position, a magnetized boundary portion of the rare earth magnet block is disposed opposite a first separator provided on the attraction portion and one of the chamfered portions is disposed opposite a second separator, thereby forming a plurality of magnetic circuits that allow magnetic flux to leak from the attraction portion, and the base portion is attracted to the magnetic member that faces the attraction portion; and when the handle portion is in a second position, a plurality of magnetic closed circuits that do not allow magnetic flux to leak between the magnetic cylindrical body and the permanent magnet rotor are formed, and the base portion releases the attraction of the magnetic member that faces the attraction portion.

10. 10. The magnetic attraction device according to claim 9, wherein the cover portion is disposed on a surface of the magnetic cylinder opposite to the attraction portion at the other end thereof, and serves as a mounting surface for a workpiece.

11. 11. The magnetic adsorption device according to claim 1, wherein the permanent magnet rotating body is rotatably supported within the housing of the device body via a bearing provided on at least one end side thereof.

Images