Linear motor and component mounting device

Abstract

This linear motor is installed on a ceiling part of a device frame. The linear motor comprises: a plate-shaped stator that extends in the horizontal direction, is fixed to the ceiling part such that both side surfaces are vertical surfaces, and has a plurality of permanent magnets each arranged on both side surfaces so as to be aligned in the horizontal direction; and a mover that is formed in a recessed shape so as to sandwich the stator from both sides and has a coil provided on a surface facing the stator so as to face the permanent magnets.

Description

Linear motor and component mounting device

[0001] This specification discloses a linear motor and a component mounting device.

[0002] Conventionally, as a Y-axis actuator for moving a head unit suspended and supported from above by a support frame, a pair of plate-shaped stators fixed to the opposing side surfaces of a pair of mounting wall portions extending in the Y direction, and a mover disposed slightly spaced from each stator between the pair of stators have been proposed (see, for example, Patent Document 1). An opening is formed in the support frame so as to linearly extend in the Y direction corresponding to the movable range of the head unit in the Y direction. The pair of mounting wall portions are formed in a plate shape and are provided so as to extend upward from the upper surface of the support frame at the edges on both sides in the X direction of the opening. The mover is fixed to the upper surface of the lower movable table via a connecting member passing through the opening, and the movable table is movably supported by the support frame via a linear bearing provided on the lower surface of the support frame.

[0003] Japanese Patent Application Laid-Open No. 2012-33736

[0004] In the above-described linear motor, since the magnetic attractive force of the permanent magnet acts inwardly on each of the pair of mounting wall portions (stators) of the device frame, it is difficult to reduce the weight of the structure for fixing the stator. For this reason, the weight of the device ceiling portion increases, and there is a risk of deteriorating the vibration characteristics.

[0005] The main object of the present disclosure is to reduce the weight of the structural member for fixing the stator and improve the vibration characteristics of the device.

[0006] The present disclosure has taken the following means to achieve the above main object.

[0007] The linear motor of this disclosure is a linear motor installed on the ceiling of a device frame, and comprises a plate-shaped stator that extends horizontally and is fixed to the ceiling such that both sides are vertical surfaces, and has a plurality of permanent magnets arranged on both sides such that they are aligned horizontally, and a movable element that is formed in a concave shape so as to sandwich the stator from both sides, and has coils provided on the surface facing the stator so as to face the permanent magnets.

[0008] In the linear motor of this disclosure, the stator is fixed to the ceiling of the device frame, and the movable element is formed in a concave shape so as to sandwich the stator from both sides. This effectively cancels out the magnetic attractive force acting on the stator. As a result, the structural members supporting the stator can be made lighter, and the vibration characteristics of the device can be improved.

[0009] The component mounting apparatus of this disclosure comprises an apparatus frame, a head moving device for moving a head in the horizontal direction, and a linear motor as a drive source for the head moving device, which includes a plate-shaped stator that extends in the horizontal direction and is fixed to the ceiling such that both sides are vertical surfaces, and has a plurality of permanent magnets arranged on both sides such that they are aligned in the horizontal direction, and a movable element that is concavely formed so as to sandwich the stator from both sides, and has coils provided on the surface facing the stator so as to face the permanent magnets.

[0010] Since the component mounting apparatus of this disclosure is equipped with the linear motor of this disclosure as the drive source for the head moving device, it can achieve the same effects as the linear motor of this disclosure.

[0011] This is a perspective view of the component mounting apparatus of this embodiment, viewed from diagonally above. This is a perspective view of the component mounting apparatus of this embodiment, viewed from diagonally below. This is a front view of the component mounting apparatus of this embodiment. This is a partial enlarged view centered on the linear motor in the component mounting apparatus of Figure 3.

[0012] Next, the forms for implementing this disclosure will be described with reference to the drawings.

[0013] Figure 1 is a perspective view of the component mounting apparatus 10 of this embodiment, viewed from diagonally above. Figure 2 is a perspective view of the component mounting apparatus 10 of this embodiment, viewed from diagonally below. Figure 3 is a front view of the component mounting apparatus 10 of this embodiment. Figure 4 is a partially enlarged view of the component mounting apparatus 10 of Figure 3, centered on the linear motor 30. In Figures 1 to 3, the X direction is the substrate transport direction, the Z direction is the vertical direction, and the Y direction is perpendicular to the X and Z directions.

[0014] The component mounting apparatus 10 of this embodiment has a component supply device (not shown) mounted on its front, and collects electronic components supplied from the component supply device and mounts them onto a substrate. As shown in Figures 1 to 3, this component mounting apparatus 10 comprises an apparatus frame 11 installed on a base (not shown), and first and second head moving devices 21 and 22 arranged in the X direction.

[0015] As shown in Figure 1, the device frame 11 comprises a main frame 12 having a box-shaped outer shape with dimensions in the X and Y directions that are approximately the same as the base, and a ceiling frame 13 installed on top of the main frame 12.

[0016] The main frame 12 has a gate-shaped front wall portion 121 erected at the front end of the base, a rear wall portion 122 erected at the rear end of the base, and a right side wall portion 123 and a left side wall portion 124 erected at the right and left ends of the base, respectively, extending parallel to each other in the Y direction and connected to the left and right sides of the front wall portion 121 and the left and right sides of the rear wall portion 122. The right side wall portion 113 and the left side wall portion 114 have openings 113a and 114a, respectively, through which substrates being transported in the X direction can pass.

[0017] The ceiling frame 13 supports the first and second head moving devices 21 and 22. The ceiling frame 13 includes a rectangular and annular support base 131 fixed to the upper end surfaces of the front wall portion 121, the rear wall portion 122, the right side wall portion 123, and the left side wall portion 124; a right side wall portion 133 erected on the right side of the upper surface of the support base 131; a left side wall portion 134 erected on the left side of the upper surface of the support base 131; a central beam 132 spanning the front and rear ends of the upper surface of the support base 131; and first and second support beams 137 and 138 spanning the front and rear ends of the upper surface of the support base 131 parallel to the central beam 132. The central beam 132 is a long member and spans the central part in the X direction of the front end of the upper surface of the support base 131 and the central part in the X direction of the rear end. The first and second support beams 137 and 138 are elongated, rectangular tubular members, and are provided on both the left and right sides of the central beam 132. In this embodiment, as shown in Figure 1, rectangular tubular support members 135L and 136L are installed on the left side of the crossing position of the central beam 132 at the front and rear ends of the upper surface of the support base 131, so as to be along the front and rear ends. The first support beam 137 is spanned between the support member 135L installed on the left side of the front end of the support base 131 and the support member 136L installed on the left side of the rear end. The first support beam 137 is fixed to the left side wall portion 134 by a fixing member 139L. In addition, rectangular tubular support members 135R and 136R are installed on the right side of the crossing position of the central beam 132 at the front and rear ends of the upper surface of the support base 131, so as to be along the front and rear ends. The second support beam 138 spans between a support member 135R installed on the right side of the front end of the upper surface of the support base 131 and a support member 136R installed on the right side of the rear end. The second support beam 138 is then fixed to the right side wall 133 by a fixing member 139R.

[0018] The first head moving device 21 includes a first X-axis moving device (not shown) for moving the first head (not shown) in the X direction, and a first Y-axis moving device for moving the first head in the Y direction. The second head moving device 22 includes a second X-axis moving device (not shown) for moving the second head (not shown) in the X direction, and a second Y-axis moving device for moving the second head in the Y direction.

[0019] As shown in Figure 3, the first Y-axis moving device of the first head moving device 21 includes a pair of first Y-axis linear guide rails (first left rail 211L, first right rail 211R) extending parallel to the Y direction at a predetermined interval in the X direction, a suspended first Y-axis slider 213 that is movablely suspended from the pair of first Y-axis linear guide rails via a linear guide block 212, and a first Y-axis actuator that drives the first Y-axis slider 213. The first left rail 211L is fixed to the left end of the lower surface of the support base 132, and the first right rail 211R is fixed to the lower surface of the central beam 132. The first head is installed on the first Y-axis slider 213 via the first X-axis moving device, and the first head moving device 21 moves the first head in the XY direction by driving the first X-axis moving device and the first Y-axis moving device.

[0020] The second Y-axis moving device of the second head moving device 22, like the first Y-axis moving device, comprises a pair of second Y-axis linear guide rails (second left rail 221L, second right rail 221R) extending parallel to the Y-direction at a predetermined interval in the X-direction, a suspended second Y-axis slider 223 movably suspended from the pair of second Y-axis linear guide rails via a linear guide block 222, and a second Y-axis actuator that drives the second Y-axis slider 223. The second left rail 221L is fixed to the lower surface of the central beam 132, and the second right rail 221R is fixed to the right end of the lower surface of the support base 132. The second head is installed on the second Y-axis slider 223 via the second X-axis moving device, and the second head moving device 22 moves the second head in the XY direction by driving the second X-axis moving device and the second Y-axis moving device.

[0021] The first Y-axis actuator of the first head moving device 21 and the second Y-axis actuator of the second head moving device 22 are both composed of linear motors 30.

[0022] As shown in Figures 3 and 4, the linear motor 30 comprises a stator 31, a pair of movable elements 32, and a connecting member 33. The stator 31 has a plate-shaped yoke plate 311 that extends in the Y direction and is fixed to the lower surface of a rectangular tubular support beam (first support beam 137, second support beam 138) with both sides being vertical planes, and a plurality of permanent magnets 312 arranged on both sides of the yoke plate 311 so as to have alternating polarities along the Y direction. The pair of movable elements 32 are arranged to sandwich the stator 31 from both the left and right sides, and are formed to have a concave shape when viewed in the Y direction, which is the direction of travel of the movable elements 32, by the connecting member 33. The pair of movable elements 32 (the concave side portions) are provided with a plurality of coils 321 wound around a core so as to face the permanent magnets 312. The connecting member 33 connects a pair of movable elements 32 and also connects them to the Y-axis sliders (first Y-axis slider 213, second Y-axis slider 223). As a result, the stator 31 is supported by the ceiling frame 13 (support base 131) via the support beams (first support beam 137, second support beam 138). The movable elements 32 are also supported so as to be movable in the Y direction relative to the ceiling frame 13 (support base 131) via the connecting member 33, the Y-axis sliders (first Y-axis slider 213, second Y-axis slider 223), and the linear guide blocks 212, 222.

[0023] Furthermore, a cooling member 34 for cooling the movable elements 32 is installed on the side of the pair of movable elements 32 opposite to the stator 31. The cooling member 34 comprises a heat sink 341 installed in close contact with the movable elements 32 so as to be able to transfer heat with the heat-generating part (coil 321) of the movable elements 32, and a fan 342 that blows air onto the fins of the heat sink 341.

[0024] As described above, in the linear motor 30 of this embodiment, the stator 31 is formed in a plate shape and fixed to the ceiling frame 13 (support base 131) of the device frame 11 via support beams (first support beam 137, second support beam 138) so that both sides are vertical surfaces, and the movable element 32 is formed in a concave shape when viewed from the direction of travel of the movable element 32 so as to sandwich the stator 31 from both sides. This makes it possible to effectively cancel out the magnetic attractive force acting on the stator 31. As a result, the structural members (first support beam 137, second support beam 138) for fixing the stator 31 can be made lighter, and the vibration characteristics of the component mounting device 20 can be improved.

[0025] Here, the correspondence between the main elements of this embodiment and the main elements of the present disclosure will be explained. Specifically, the device frame 11 of this embodiment is an example of the device frame of the present disclosure, the stator 31 is an example of a stator, and the movable element 32 is an example of a movable element. Also, the first support beam 137 and the second support beam 138 are examples of the first bracket. Furthermore, the connecting member 33 and the first and second Y-axis sliders 213 and 223 are examples of the second bracket.

[0026] It goes without saying that this disclosure is not limited in any way to the embodiments described above, and can be implemented in various forms as long as they fall within the technical scope of this disclosure.

[0027] For example, in the embodiment described above, the linear motor 30 was used as an actuator for the Y-axis moving device, but it may also be used as an actuator for the X-axis moving device.

[0028] As described above, in the linear motor of this disclosure, the stator is fixed to the ceiling of the device frame, and the movable element is formed in a concave shape so as to sandwich the stator from both sides. This effectively cancels out the magnetic attractive force acting on the stator. As a result, the structural members supporting the stator can be made lighter, and the vibration characteristics of the device can be improved.

[0029] In the linear motor of this disclosure, the device frame is provided with a first bracket for fixing the stator to the ceiling portion, wherein the first bracket is a member extending in the horizontal direction, and the stator may be fixed to the bottom surface of the first bracket. In this way, the structural member supporting the stator can be easily made lighter while ensuring sufficient strength.

[0030] In this case, the first bracket may be positioned so as to span across both ends of the ceiling portion in the horizontal direction. This allows the stator to be easily held in a horizontal position using the first bracket.

[0031] Furthermore, the linear motor of this disclosure includes a pair of linear guides supported by the device frame and guiding the movement of the movable element, and a second bracket extending in a direction horizontal to and perpendicular to the direction of travel of the movable element, to which the movable element is fixed, wherein the pair of linear guides may movably support the second bracket at both ends in the extending direction of the second bracket. By attaching the object to be moved to the second bracket, the object to be moved can be moved smoothly.

[0032] Furthermore, this disclosure is not limited to the form of a linear motor, but may also be in the form of a component mounting device equipped with a linear motor.

[0033] This disclosure can be used in industries such as the manufacturing of linear motors.

[0034] 10 Component mounting device, 11 Device frame, 12 Main frame, 13 Ceiling frame, 20 Component mounting device, 21 First head moving device, 22 Second head moving device, 30 Linear motor, 31 Stator, 32 Movable element, 33 Connecting member, 34 Cooling member, 113 Right side wall section, 113a Opening, 114 Left side wall section, 114a Opening, 121 Front wall section, 122 Rear wall section, 123 Right side wall section, 124 Left side wall section, 131 Support base, 132 Central beam, 133 Right side wall section, 134 Left side wall section, 135L, 135R, 136L, 136R Support members, 137 First support beam, 138 Second support beam, 139L, 139R Fixing members, 211L First left rail, 211R First right rail, 212, 222; linear guide block, 213; first Y-axis slider, 221L; second left rail, 221R; second right rail, 223; second Y-axis slider, 311; yoke plate, 312; permanent magnet, 321; coil, 341; heat sink, 342; fan.

Claims

1. A linear motor installed on the ceiling of a device frame, comprising: a plate-shaped stator that extends horizontally and is fixed to the ceiling such that both sides are vertical surfaces, and has a plurality of permanent magnets arranged on both sides such that they are aligned horizontally; and a movable element that is concave in shape so as to sandwich the stator from both sides, and has coils provided on the surface facing the stator so as to face the permanent magnets.

2. A linear motor according to claim 1, comprising a first bracket for fixing the stator to the ceiling portion of the device frame, wherein the first bracket is a member extending in the horizontal direction, and the stator is fixed to the bottom surface of the first bracket.

3. A linear motor according to claim 2, wherein the first bracket is arranged to span across both ends of the ceiling portion in the horizontal direction.

4. A linear motor according to any one of claims 1 to 3, comprising: a pair of linear guides supported on the device frame and guiding the movement of the movable element; and a second bracket extending in a direction perpendicular to the direction of travel of the movable element and to which the movable element is fixed, wherein the pair of linear guides movably support the second bracket at both ends in the extending direction of the second bracket.

5. A component mounting apparatus comprising: a device frame; a head moving device for moving a head in the horizontal direction; a linear motor as a drive source for the head moving device, which includes a plate-shaped stator that extends in the horizontal direction and is fixed to the ceiling such that both sides are vertical surfaces, and has a plurality of permanent magnets arranged on both sides such that they are aligned in the horizontal direction; and a movable element that is concave in shape so as to sandwich the stator from both sides, and has coils provided on the surface facing the stator so as to face the permanent magnets.

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