JPWO2013105208A1 - Linear motor - Google Patents

Abstract

In a linear motor provided with a mover having a cylindrical coil and a shaft-like stator that penetrates the inside of the coil, the mover is (a) a magnetic body disposed so as to cover the outer peripheral surface of the coil And (b) a heat-dissipating member having a heat-collecting part attached to the outer peripheral surface of the magnetic body and a heat-dissipating part that is continuous from the heat-collecting part and extends outward in the radial direction of the coil. With this configuration, the magnetic flux can be efficiently passed through the coil, and the motor can be increased in thrust. In addition, heat generated in the coil can be efficiently released to the outside of the coil, and heat dissipation characteristics can be improved.

Description

  The present invention relates to a linear motor in which a movable part has a cylindrical coil and a stator penetrates the inside of the coil.

  Some linear motors have a structure in which a movable portion has a cylindrical coil and a stator penetrates the inside of the coil, and is called a shaft motor. A linear motor such as a shaft motor has a problem that the coil generates heat during driving, and it is desired to improve the heat dissipation characteristics of the coil. It is also desired to increase the thrust in order to improve the ability as a motor. The following patent documents describe techniques for improving the heat dissipation characteristics and increasing the thrust of the coil.

JP-A-9-182408 JP 2002-247830 A

  According to the linear motor described in the above-mentioned patent document, it is possible to improve the heat dissipation characteristics and increase the thrust to some extent. However, there is still much room for improvement, and it is desired to further improve the heat dissipation characteristics and increase the thrust. This invention is made | formed in view of such a situation, and makes it a subject to provide the linear motor which can aim at the further improvement of a thermal radiation characteristic, and high thrust.

  In order to solve the above problems, a linear motor according to claim 1 of the present application includes a mover having a cylindrical coil and a shaft-like stator that penetrates the inside of the coil, and the mover is A magnetic body disposed so as to cover the outer peripheral surface of the coil, a heat collecting portion attached to the outer peripheral surface of the magnetic body, and continuous from the heat collecting portion and extending outward in the radial direction of the coil. A heat dissipating member having a heat dissipating part.

  According to a second aspect of the present invention, there is provided the linear motor according to the first aspect, wherein the magnetic body is formed of electromagnetic steel.

  According to a third aspect of the present invention, there is provided the linear motor according to the first or second aspect, wherein the magnetic material has a saturation magnetic flux density of 1.8 T or more.

  The linear motor according to claim 4 is the linear motor according to any one of claims 1 to 3, wherein the thermal conductivity of the magnetic body is 20 W / (m · K) or more. Configured as follows.

  According to a fifth aspect of the present invention, there is provided the linear motor according to any one of the first to fourth aspects, wherein the magnetic body has a cylindrical shape and extends in the axial direction. It is comprised so that it may have the notch part made.

  A linear motor according to a sixth aspect is the linear motor according to the fifth aspect, wherein the radial thickness of the magnetic body is 0.5 mm or more.

  The linear motor according to claim 7 is the linear motor according to any one of claims 1 to 6, wherein the heat collecting portion is disposed along an outer peripheral surface of the magnetic body. The heat radiating portion extends outside the housing of the mover, and the mover includes a spacer that is press-fitted between the heat collecting portion and the housing.

  According to an eighth aspect of the present invention, in the linear motor according to the seventh aspect, the spacer is configured to have a wedge shape.

  The linear motor according to claim 9 is the linear motor according to claim 7 or 8, wherein the spacer is press-fitted between the heat collecting portion and the housing. It is comprised so that it may deform | transform along the outer peripheral surface of a part.

  The linear motor according to claim 10 is the linear motor according to any one of claims 1 to 6, wherein the heat collecting portion is fixed to the outer peripheral surface of the magnetic body by soldering. Configured to be attached.

  In the linear motor according to the first aspect, the magnetic body is disposed so as to cover the outer peripheral surface of the coil. In a linear motor, normally, a magnetic flux generated by a permanent magnet flows in the coil, and when a drive current is supplied to the coil, the interaction between the magnetic flux flowing in the coil and the current supplied to the coil Thrust is generated. For this reason, by covering the outer peripheral surface of the coil with a magnetic material that allows easy flow of magnetic flux, the magnetic flux generated by the permanent magnet can be efficiently flowed into the coil, and thrust can be generated efficiently. It becomes. That is, the magnetic body functions as a yoke, and the magnetic body allows the magnetic flux flowing in the coil to be concentrated in a direction that can be efficiently converted into a thrust, thereby achieving high thrust.

  Furthermore, in the linear motor according to the first aspect, the heat collecting portion of the heat radiating member is attached to the outer peripheral surface of the magnetic body, and the heat radiating portion of the heat radiating member extends outward in the radial direction of the coil. Thereby, it becomes possible to discharge | release the heat of a coil suitably to the exterior of a motor. More specifically, the heat of the coil is transmitted to a magnetic body provided on the outer peripheral surface of the coil. In a magnetic body, in general, not only the magnetic flux easily flows but also the heat is easily transmitted, so that the heat of the coil is efficiently transmitted to the magnetic body. And the heat transmitted to the magnetic body is transmitted to the heat collecting section that covers the outer peripheral surface of the magnetic body, and is released from the heat radiating section that extends to the outside of the coil. Thereby, it becomes possible to discharge | release the heat | fever of a coil suitably to the exterior of a motor, and it becomes possible to implement | achieve the linear motor excellent in the thermal radiation characteristic.

  In the linear motor according to claim 2, the magnetic body is formed of electromagnetic steel. Magnetic steel has high magnetic flux density, magnetic permeability, etc., and magnetic flux easily flows in the magnetic steel. For this reason, according to the linear motor of Claim 2, it becomes possible to aim at the high thrust of a motor efficiently. The “electromagnetic steel” described in this section may be an electromagnetic steel manufactured by adding silicon to iron, so-called silicon steel, or an electromagnetic steel not containing silicon.

  In the linear motor according to claim 3, the saturation magnetic flux density of the magnetic material is set to 1.8 T or more, and the outer peripheral surface of the coil is covered with the magnetic material in which the magnetic flux easily flows. Thereby, a linear motor capable of generating high thrust can be realized.

  In the linear motor according to the fourth aspect, the thermal conductivity of the magnetic material is 20 W / (m · K) or more, and heat is easily transmitted. Thereby, it becomes possible to transmit the heat of a coil to a heat radiating member suitably.

  In the linear motor according to the fifth aspect, the magnetic body is formed in a cylindrical shape, and a notch extending in the axial direction is formed. As a result, the magnetic body covers substantially the entire circumference of the outer peripheral surface of the coil, and wiring for energizing the coil can be performed through the notch.

  In the linear motor according to claim 6, the thickness of the magnetic body is set to 0.5 mm or more. If the thickness of the magnetic material is too thin, the magnetic flux is easily saturated and the magnetic flux is difficult to flow. For this reason, according to the linear motor of Claim 6, it becomes possible to ensure the easiness of the flow of magnetic flux.

  In the linear motor according to claim 7, a spacer is press-fitted between the heat collecting portion of the heat radiating member and the housing of the mover, and the heat collecting portion is directed toward the outer peripheral surface of the magnetic body by the spacer. Pressed. As a result, the heat collecting part and the magnetic body can be reliably brought into close contact with each other, and the contact area between the heat collecting part and the magnetic body can be increased. Therefore, according to the linear motor of the seventh aspect, the heat generated in the coil is easily transmitted from the magnetic body to the heat collecting portion of the heat radiating member, and it is possible to further improve the heat radiation characteristics. .

  In the linear motor according to the eighth aspect, the spacer has a wedge shape. As a result, the spacer can be easily press-fitted between the heat collecting part and the housing, and the heat collecting part and the magnetic body can be suitably brought into close contact with each other.

  In the linear motor according to the ninth aspect, the spacer press-fitted between the heat collecting portion and the housing is deformed along the outer peripheral surface of the heat collecting portion. Thereby, it is possible to suppress excessive pressing of the heat collecting part to the magnetic body, and it is possible to suppress an excessive increase in the load applied between the heat collecting part and the magnetic body.

  In the linear motor according to claim 10, the heat collecting part and the magnetic body are joined by soldering. Thereby, the heat generated in the coil can be transmitted from the magnetic body to the heat collecting part via the solder having high thermal conductivity, and the heat dissipation characteristics can be improved.

It is a top view which shows an electronic component mounting machine provided with the shaft motor which is an Example of this invention. It is sectional drawing which shows the shaft motor with which the electronic component mounting machine shown in FIG. 1 is provided. It is a perspective view which shows the shaft motor shown in FIG. 2 in the state which removed the housing and the resin mold. It is sectional drawing which shows the shaft motor of the modification 1. It is sectional drawing which shows the shaft motor of the modification 2. It is sectional drawing which shows the shaft motor of the modification 3. It is a perspective view which shows the shaft motor of the modification 4 in the state except the resin mold. It is a perspective view which shows the shaft motor of the modification 5 in the state which removed the housing and the resin mold.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments and modifications of the present invention will be described in detail with reference to the drawings as modes for carrying out the present invention.

<Configuration of electronic component mounting machine>
FIG. 1 shows an electronic component mounting machine 10. FIG. 1 is a schematic plan view showing the electronic component mounting machine 10 with the upper cover removed from a viewpoint from above. The electronic component mounting machine 10 performs an operation of mounting an electronic circuit component (hereinafter abbreviated as “electronic component”) on the circuit board 12, and includes a transport device 14 that transports the circuit board 12, and a circuit board. A work head 16 for mounting the electronic component, a moving device 18 for moving the work head 16, and a pair of supply devices 20 and 22 for supplying the electronic component.

  The transport device 14 has a pair of conveyor belts 30 provided on a base 28, and is supported by the conveyor belt 30 by rotating the pair of conveyor belts 30 by an electromagnetic motor (not shown). The circuit board 12 is transported. Further, the transfer device 14 includes a substrate holding device 32, and is configured to hold the circuit board 12 in a fixed position (a position where the circuit board 12 in the drawing is illustrated). In the present embodiment, the transport direction of the circuit board 12 by the transport device 14 (the left-right direction in FIG. 1) is referred to as an X-axis direction, and a direction perpendicular to the direction is referred to as a Y-axis direction.

  Further, the pair of supply devices 20 and 22 are disposed on both side portions of the base 28 in the Y-axis direction so as to sandwich the transport device 14. Each of the pair of supply devices 20 and 22 is a feeder-type supply device, and has a plurality of tape feeders 36 that hold the taped electronic components and send out the electronic components one by one. Each of the plurality of tape feeders 36 is configured to supply an electronic component to a supply position to the work head 16.

  The work head 16 is a mounting head for mounting an electronic component on the circuit board 12 held by the transport device 14 and having a suction nozzle 38 for sucking the electronic component on the lower surface. The suction nozzle 38 communicates with negative pressure air and a positive pressure air passage via a positive / negative pressure supply device (not shown), and sucks and holds the electronic component with a negative pressure so that a slight positive pressure is supplied. It is structured to release the held electronic component. Furthermore, the work head 16 has a nozzle lifting / lowering device (not shown) that lifts and lowers the suction nozzle 38, and can change the vertical position of the electronic component to be held.

  The working head 16 can be moved to an arbitrary position on the base 28 by the moving device 18. Specifically, the moving device 18 includes an X-axis direction slide mechanism 50 for moving the work head 16 in the X-axis direction, and a Y-axis direction slide mechanism 52 for moving the work head 16 in the Y-axis direction. ing. The X-axis direction slide mechanism 50 has an X-axis slider 54 provided on the base 28 so as to be movable in the X-axis direction, and a pair of shaft motors 56 as a drive source. 56, the X-axis slider 54 can be moved to an arbitrary position in the X-axis direction. The Y-axis direction slide mechanism 52 includes a Y-axis slider 58 provided on the side surface of the X-axis slider 54 so as to be movable in the Y-axis direction, and a linear motor 60 as a drive source. Thus, the Y-axis slider 58 can be moved to an arbitrary position in the Y-axis direction. By attaching the working head 16 to the Y-axis slider 58, the working head 16 can be moved to an arbitrary position on the base 28 by the moving device 18. The work head 16 can be attached to and detached from the Y-axis slider 58 with one touch, and can be changed to a different type of work head, such as a dispenser head.

<Configuration of shaft motor>
Each of the pair of shaft motors 56 that is a drive source of the X-axis direction sliding mechanism 50 for moving the work head 16 in the X-axis direction is a cylindrical linear motor, as shown in FIGS. 1 and 2. A movable element 72 having a plurality of cylindrical coils (only one is shown in FIG. 2) 70 and a shaft-shaped stator 74 penetrating the inside of the coil 70 are provided. The stator 74 of each shaft motor 56 is disposed between the transport device 14 and the supply devices 20 and 22 so as to extend in the X-axis direction, and is supported by a pair of support members 76 at both ends. It is stretched over the base 28.

  The stator 74 is configured by a cylindrical pipe 78 and a plurality of permanent magnets 80 (only one is shown in FIG. 2) disposed in the pipe 78. Each of the plurality of permanent magnets 80 is generally cylindrical, and one end side is an N pole, and the other end side is an S pole. The plurality of permanent magnets 80 are arranged so as to extend on one axis, and the opposite end portions of two adjacent permanent magnets 80 have the same magnetic pole. A spacer (not shown) made of a nonmagnetic material is provided between two adjacent permanent magnets 80. On the other hand, the pipe 78 is provided so as to cover a plurality of permanent magnets 80 arranged to extend on one axis, and is made of a nonmagnetic material.

  Each of the plurality of coils 70 of the mover 72 is formed into a cylindrical shape by winding a wire, and a gap between the wires is filled with resin. The plurality of coils 70 are provided concentrically at equal intervals, and an annular spacer (not shown) made of a nonmagnetic material is provided between two adjacent coils 70. The outer peripheral surfaces of the plurality of coils 70 and the spacer are covered with a covering member 82 made of a magnetic material. The covering member 82 is formed into a cylindrical shape by electromagnetic steel, specifically, silicon steel having a saturation magnetic flux density of 1.8 T or more and a thermal conductivity of 20 W / (m · K) or more. The thickness in the direction is 0.5 mm. The covering member 82 is formed with a notch 83 extending in the axial direction, and a current-carrying wiring (not shown) is connected to the coil 70 through the notch 83.

  The plurality of coils 70 and the spacers covered with the covering member 82 are fitted on the outer peripheral surface of the stator 74 with a clearance, and can be moved in the axial direction of the stator 74, that is, in the X-axis direction. ing. Thereby, the mover 72 is movable on the base 28 in the X-axis direction.

  A heat radiating member 84 is provided on the outer peripheral surface of the covering member 82. The heat dissipating member 84 is formed by bending a metal material having high heat conductivity and excellent heat dissipating characteristics (heat dissipating amount / mass) per unit mass, specifically, a copper member. More specifically, the heat radiating member 84 is composed of a plurality of copper tubes 85 as shown in FIG. The copper tube 85 is compressed in the radial direction with a space inside, and the space inside the copper tube 85 is filled with water. That is, a heat pipe is employed as the heat radiating member 84. Thereby, the heat dissipation characteristic of the heat radiating member 84 is further improved. Incidentally, FIG. 3 shows the shaft motor 56 in a state where a housing and a resin mold described later are removed.

  The copper tube 85 is divided into an arc portion 86 disposed along the outer peripheral surface of the covering member 82 and an extending portion 88 that continues from the arc portion 86 and extends outward in the radial direction of the covering member 82. The arc portion 86 covers the outer peripheral surface of the covering member 82 by about 1/3 in the circumferential direction thereof, and the curvature of the inner surface of the arc portion 86 and the curvature of the outer peripheral surface of the covering member 82 are substantially the same. Has been.

  The extension part 88 of the copper tube 85 extends to the outside of the housing 90 of the mover 72, and fins 92 are provided in the extended part. The fin 92 has a high thermal conductivity and is formed by bending a metal material excellent in heat dissipation characteristics (heat dissipation amount / mass) per unit mass, specifically, a thin plate made of an aluminum alloy into an uneven shape. ing. The fin 92 has a length approximately the same as the length of the mover 72 in the axial direction, and a pair of fans 94 are provided at both ends of the fin 92. One of the pair of fans 94 is configured to blow air toward the inside of the fin 92 and the other is blown toward the outside. As a result, the heat passes through the fins 92 to improve heat dissipation characteristics.

  The housing 90 of the mover 72 has a groove shape as shown in FIG. 2, and the covering member 82 having the heat radiating member 84 attached to the outer peripheral surface connects the extended portion 88 of the copper tube 85 to the housing 90. The housing 90 is housed in a state of extending to the outside. Of the pair of side walls 96 of the housing 90, the side wall 96 a on the side from which the extending portion 88 extends faces the outer peripheral surface of the covering member 82 and is in contact with the outer peripheral surface. The other side wall 96 b faces the arc portion 86 of the copper tube 85 that covers the outer peripheral surface of the covering member 82, and there is a gap between the side wall 96 b and the arc portion 86. A wedge-shaped spacer 98 is press-fitted into the gap, and the thickness of the rear end portion of the spacer 98, that is, the end portion on the thick side, is thicker than the gap between the arc portion 86 and the side wall 96b. As a result, the arc portion 86 of the copper tube 85 can be pressed toward the covering member 82, and the inner surface of the arc portion 86 and the outer peripheral surface of the covering member 82 are brought into close contact with each other.

  The covering member 82 to which the copper tube 85 is attached and the spacer 98 that closely contacts the covering member 82 and the arc portion 86 are sealed in the housing 90 by the resin mold 100. The resin of the resin mold 100 is the same as the resin filled in the gaps between the wires of the coil 70.

  Further, a table 102 is fixed to the upper portion of the movable element 72, specifically, the upper surface of the resin mold 100 and the upper surface of the extending portion 88 of the copper tube 85, and the X-axis slider 54 (see FIG. 2 is omitted). The table 102 can be slid by the slide mechanism 104 in the axial direction of the stator 74, that is, in the X-axis direction. Specifically, the slide mechanism 104 includes a pair of slide rails 106 disposed on the base 28, a pair of sliders 108 fitted to the pair of slide rails 106 so as to be relatively movable, and the slide rail 106. And a linear bearing 110 disposed between the slider 108 and the slider 108. The pair of slide rails 106 are arranged so as to extend in the X-axis direction with the stator 74 interposed therebetween, and a pair of slide rails 106 fitted to the pair of slide rails 106 via linear bearings 110. The slider 108 is fixed to the lower surface of the table 102. Thereby, the table 102, that is, the X-axis slider 54 is slidable in the X-axis direction.

  With the configuration described above, in the shaft motor 56, the magnetic flux generated by the permanent magnet 80 flows in the coil. When a drive current is supplied to the coil 70, an axial movement thrust is generated by the interaction between the magnetic flux flowing in the coil 70 and the current supplied to the coil 70. By this thrust, the mover 72 is moved in a direction parallel to the axis of the stator 74, and the table 102, that is, the X-axis slider 54 is moved in the X-axis direction.

  In the shaft motor 56 of the present embodiment, the outer peripheral surface of the coil 70 is covered with a covering member 82 made of a magnetic material having a high saturation magnetic flux density, and the magnetic flux generated by the permanent magnet 80 is efficiently generated by the covering member 82. In the coil 70. That is, the covering member 82 functions as a yoke, and the covering member 82 concentrates the magnetic flux flowing in the coil 70 in a direction that can be efficiently converted into the thrust. As a result, the magnetic flux flowing in the coil can be efficiently converted into the thrust, and the shaft motor 56 can be increased in thrust.

  In addition, when the drive current is supplied to the coil 70, the coil 70 generates heat, but the heat is transmitted to the covering member 82 provided on the outer peripheral surface of the coil 70 with high thermal conductivity. Then, the heat is transmitted to the arc portion 86 of the heat radiating member 84 that covers the outer peripheral surface of the covering member 82, and is released from the extending portion 88 and the fin 92 of the heat radiating member 84 to the outside of the mover 72. Is done. Thereby, it becomes possible to realize a shaft motor excellent in heat dissipation characteristics. Furthermore, high thrust can be generated by improving the heat dissipation characteristics. For this reason, in the shaft motor 56 of the present embodiment, it is possible to further increase the thrust.

  Further, in the shaft motor 56 of the present embodiment, the inner surface of the arc portion 86 of the heat radiating member 84 and the outer peripheral surface of the covering member 82 are in close contact with each other by the spacer 98, and the arc portion 86 and the covering member 82 are in close contact with each other. The contact area is relatively large. Thereby, the heat generated in the coil 70 can be easily transmitted from the covering member 82 to the arc portion 86, and the heat dissipation characteristics can be further improved.

<Modification>
In the shaft motor 56 of the above embodiment, the spacer 98 press-fitted between the side wall 96b of the housing 90 and the arc portion 86 of the heat radiating member 84 has a wedge shape, and a relatively high rigidity is employed. . However, the shape of the spacer press-fitted between the side wall 96b and the arc portion 86 is not limited to the wedge shape, and various shapes of spacers can be employed. Further, the material of the spacer may be a material having low rigidity, and it is possible to adopt a material formed from various materials.

  A shaft motor provided with a spacer formed of a material different from the spacer 98 of the above embodiment is shown in FIG. 3 as a shaft motor 120 of the first modification, and a shaft motor provided with a spacer having a different shape from the spacer 98 of the above embodiment. Is shown in FIG. 4 as the shaft motor 122 of the second modification. The shaft motors 120 and 122 of the respective modifications have the same configuration as that of the shaft motor 56 of the above-described embodiment except for the spacers. Therefore, the same components as those of the shaft motor 56 are described using the same reference numerals. Is omitted or simplified.

  As shown in FIG. 4, the shaft motor 120 of Modification 1 has a wedge-shaped spacer 124, and the spacer 124 is press-fitted between the side wall 96 b of the housing 90 and the arc portion 86 of the copper tube 85. ing. The spacer 124 is formed of a material having rigidity lower than that of the copper tube 85, and the spacer 124 is deformed along the outer peripheral surface of the arc portion 86 by being press-fitted between the side wall 96b and the arc portion 86. doing. This makes it possible to suppress excessive pressing of the arc portion 86 of the copper tube 85 to the covering member 82, and an excessive load applied between the inner surface of the arc portion 86 and the outer peripheral surface of the covering member 82. The increase can be suppressed.

  The material of the spacer 124 of Modification 1 may be any material as long as the spacer 124 deforms along the outer peripheral surface of the arc portion 86 when press-fitted between the side wall 96 b and the arc portion 86. It is possible to employ various materials such as a metal material having a lower rigidity than the above-described rigidity and an elastic body having flexibility. The spacer 124 can be deformed in various forms such as plastic deformation and elastic deformation.

  Moreover, the shaft motor 122 of the modification 2 has the flat spacer 126 as shown in FIG. The spacer 126 is press-fitted between the side wall 96 b of the housing 90 and the arc portion 86 of the copper tube 85, and the inner surface of the arc portion 86 of the copper tube 85 and the outer peripheral surface of the covering member 82 are preferably in close contact with each other. ing. As described above, the spacer press-fitted between the side wall 96b and the arc part 86 has any shape, and the inner surface of the arc part 86 of the copper tube 85 and the outer peripheral surface of the covering member 82 Can be suitably adhered. The flat spacer 126 is formed of a material having high rigidity, but may be formed of a material having low rigidity in the same manner as the spacer 124 of Modification 1.

  In the shaft motors 56, 120, and 122 of the above embodiment and the first and second modifications, the inner surface of the arc portion 86 of the copper tube 85 and the outer peripheral surface of the covering member 82 are brought into close contact by the spacers 98, 124, and 126. However, the inner surface of the arc portion 86 and the outer peripheral surface of the covering member 82 may be in close contact with each other by a different one from the spacer. A shaft motor in which the inner surface of the arc portion 86 and the outer peripheral surface of the covering member 82 are in close contact with each other by a different one from the spacer is shown as a shaft motor 130 of Modification 3 in FIG. The shaft motor 130 of the third modification has substantially the same configuration as that of the shaft motor 56 of the above embodiment except that the inner surface of the arc portion 86 and the outer peripheral surface of the covering member 82 are in close contact with each other. The same components as those of the shaft motor 56 are denoted by the same reference numerals, and description thereof is omitted or simplified.

  In the shaft motor 130 of the third modification, as shown in FIG. 6, the spacer is not press-fitted between the side wall 96 b of the housing 90 and the arc portion 86 of the copper tube 85, and the arc portion 86 of the copper tube 85 is not pressed. The inner surface and the outer peripheral surface of the covering member 82 are joined by solder 132. That is, the inner surface of the arc portion 86 and the outer peripheral surface of the covering member 82 are in close contact with each other via the solder 132. As a result, heat generated in the coil 70 is transmitted from the covering member 82 to the arc portion 86 via the solder 132 having high thermal conductivity, and high heat dissipation characteristics can be ensured. The outer peripheral surface of the covering member 82 is subjected to nickel plating.

  Incidentally, in the above-described embodiments and modifications, the shaft motors 56, 120, 122, and 130 are examples of linear motors, and the mover 72 and the stator 74 that constitute the shaft motors 56, 120, 122, and 130 are movable. It is an example of a child and a stator. The coil 70, the covering member 82, and the housing 90 are examples of a coil, a magnetic body, and a housing, and the notch 83 of the covering member 82 is an example of a notch. The spacers 98, 124, and 126 are examples of spacers, and what is constituted by the heat dissipation member 84 and the fins 92 is an example of a heat dissipation member. The arc portion 86 of the heat radiating member 84 is an example of a heat collecting portion, and what is constituted by the extending portion 88 of the heat radiating member 84 and the fins 92 is an example of a heat radiating portion.

  In addition, this invention is not limited to the said Example and modification, It is possible to implement in the various aspect which gave various change and improvement based on the knowledge of those skilled in the art. Specifically, for example, in the above-described embodiments and modifications, the shaft motor of the present invention is employed as a drive source for the X-axis direction slide mechanism 50 that moves the work head 16 in the X-axis direction. The shaft motor of the present invention can be employed as a drive source for the direction slide mechanism 52. Further, the shaft motor of the present invention can be employed as a drive source for devices and mechanisms other than the devices and mechanisms that constitute the electronic component mounting machine 10.

  Further, in the above-described embodiments and modifications, the thickness in the radial direction of the covering member 82 as the magnetic body is 0.5 mm, but is not limited to this value, and may be 0.5 mm or more. That's fine. However, the thicker the covering member 82, the heavier the covering member 82, that is, the mover 72, so the thickness of the covering member 82 is preferably about 0.5 to 3 mm.

  Further, in order to further improve the heat dissipation characteristics of the shaft motor, the fins 92 may be provided on both sides in the radial direction of the mover 72. Specifically, as shown in FIG. 7, half of the plurality of copper tubes 85 attached to the outer peripheral surface of the covering member 82 extend in one direction outside the housing 90, The extension portion 88 of the remaining half of the copper tube 85 extends in a direction opposite to the one direction. A copper tube 85a having an extending portion 88 extending in the one direction and a copper tube 85b having an extending portion 88 extending in a direction opposite to the one direction are alternately arranged on the outer peripheral surface of the covering member 82. It is attached. And the fin 92a is provided in the extension part 88a of the copper pipe 85a, and the fin 92b is provided in the extension part 88b of the copper pipe 85b. With such a structure, the fins 92 a and 92 b are provided on both sides in the radial direction of the mover 72.

  Further, the number of fans 94 attached to the fins 92 may be increased in order to improve the heat dissipation characteristics of the shaft motor. Specifically, as shown in FIG. 8, a plurality of fans 94 (six fans 94 in the figure) are arranged side by side in the axial direction of the mover 72 and attached to the side surfaces in the longitudinal direction of the fins 92. May be. As a result, the number of fans 94 attached to the fins 92 can be increased, and the heat dissipation characteristics can be improved.

  56: Shaft motor 70: Coil 72: Movable element 74: Stator 82: Cover member (magnetic body) 83: Notch part 84: Heat radiation member 86: Arc part (heat collecting part) 88: Arc part (heat radiation part) 90 : Housing 92: Fin (heat radiating member) (heat radiating part) 98: Spacer 120; Shaft motor 122: Shaft motor 124: Spacer 126: Spacer 130: Shaft motor

Claims (10)

A mover having a cylindrical coil, and a shaft-like stator that penetrates the inside of the coil,
The mover is
A magnetic body disposed so as to cover the outer peripheral surface of the coil;
A linear motor comprising: a heat collecting part attached to the outer peripheral surface of the magnetic body; and a heat radiating member that is continuous from the heat collecting part and has a heat radiating part extending toward the outside in the radial direction of the coil.   The linear motor according to claim 1, wherein the magnetic body is formed of electromagnetic steel.   The linear motor according to claim 1, wherein a saturation magnetic flux density of the magnetic body is 1.8 T or more.   The linear motor according to any one of claims 1 to 3, wherein the magnetic substance has a thermal conductivity of 20 W / (m · K) or more. The magnetic body is
5. The linear motor according to claim 1, wherein the linear motor has a notch portion that is formed in a cylindrical shape and extends in the axial direction.   The linear motor according to any one of claims 1 to 5, wherein a thickness of the magnetic body in a radial direction is 0.5 mm or more. The heat collecting portion is disposed along an outer peripheral surface of the magnetic body;
The heat dissipating part extends outside the housing of the mover;
The mover is
The linear motor according to claim 1, further comprising a spacer press-fitted between the heat collecting unit and the housing.   The linear motor according to claim 7, wherein the spacer has a wedge shape. The spacer is
9. The linear motor according to claim 7, wherein the linear motor is deformed along an outer peripheral surface of the heat collecting portion while being press-fitted between the heat collecting portion and the housing.   The linear motor according to any one of claims 1 to 6, wherein the heat collecting portion is fixedly attached to an outer peripheral surface of the magnetic body by soldering.

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