JP4731903B2 - Mounting head for component mounting, and component mounting apparatus including the mounting head - Google Patents

Description

  The present invention includes a shaft-type linear motor that linearly moves a drive shaft by supplying a drive current to a coil, a multi-axis linear motor including a plurality of the shaft-type linear motors, and the multi-axis linear motor. The present invention relates to a mounting head and a component mounting apparatus used for component mounting, and a magnetic shielding method for a multi-axis linear motor that avoids mutual interference due to magnetic force when controlling the multi-axis linear motor.

  Conventionally, as one type of linear motor, a shaft including a hollow linear stator (stator portion) and a drive shaft (movable portion) that is inserted into the hollow portion of the stator and driven linearly A type linear motor is known (see, for example, Patent Document 1). A plurality of coils that can individually control the magnetic poles are linearly arranged in the stator portion, and a shaft that is magnetized in the N and S poles along the axial direction is arranged in the movable portion. The combination of the coil and the permanent magnet can be reversed between the stator portion and the movable portion. By applying a drive current to the coil so as to generate a magnetic field that intersects the magnetic field lines of the magnetic field generated by the permanent magnet, a repulsive force is generated between them, and the movable part moves in the axial direction with respect to the stator part.

  When a multi-axis actuator with multiple shaft-type linear motors is used in an FA precision device such as a component mounting device, it has good responsiveness that enables high-speed operation and high accuracy to achieve accurate positioning Maintenance is important. In particular, when a multi-axis linear motor including a plurality of linear motors is provided as the multi-axis actuator, individual control of each axis can be reliably performed without being influenced by other axes. is important.

  Conventionally, as a position detection method for improving the positioning accuracy of a shaft type linear motor, a configuration using a linear scale for optically detecting a position (see, for example, Patent Document 2), a linear resolver has been used. (For example, refer to Patent Document 3) or a movable shaft portion provided with a driving magnetized portion and a position detecting magnetized portion, and a stator provided with a driving coil and a position detecting magnetic sensor (for example, a patent) Reference 4) is known.

Generally, a linear motor uses a magnet and an electromagnet (coil) for control and driving. In addition, among the various positioning means described above, in the method disclosed in Patent Document 4, a magnet is used not only for driving but also for detecting a moving position. In order to move the driving shaft of the linear motor by a desired amount at a desired timing, it is necessary to generate an appropriate driving force (repulsive force) between the stator portion and the movable portion. For this purpose, an appropriate magnetic force corresponding to the amount of current passed through the coil in the stator portion must be generated, and a predetermined repulsive force must be generated between the permanent magnets facing each other. Further, in order to accurately measure the moving position of the linear motor movable portion, the sensor for detection must be able to accurately grasp the strength of the magnetic field magnetized on the object to be measured.
Japanese Patent Laid-Open No. 10-313566 JP 2000-262034 A JP 2003-32995 A JP-A-7-107706

  However, a multi-axis linear motor provided with a plurality of shaft-type linear motors (hereinafter simply referred to as “linear motors”) according to the prior art, and a mounting head used in a component supply apparatus using the multi-axis linear motor, etc. There was a problem with precise control and operation. For example, in a mounting head or the like, in order to increase the efficiency of component mounting, it is desired to incorporate a shaft for sucking as many components as possible into one mounting head, that is, a suction nozzle assembly. At the same time, since the mounting head is transported at high speed by an XY robot, etc., make the mounting head itself as small and light as possible in order to minimize the moment of inertia during movement and to minimize vibration during stoppage. Is required.

  However, when trying to realize the above requirements, it is important to arrange a plurality of linear motors as close as possible. However, this approach reduces the distance between the linear motors, so it is included in each linear motor. The lines of magnetic force from the permanent magnets and electromagnets affect each other, which hinders control of the linear motor and detection of the moving position of the movable part.

  How close the distance between linear motors is to cause the above-mentioned control obstacles depends on the specifications of each linear motor, that is, the strength of the magnetic force of the permanent magnet or coil (electromagnet) used, I can't say anything. It has been found that the degree of failure at this time is particularly affected by the maximum energy product (BHmax) of the magnet, that is, the maximum value of the product of residual magnetic flux density (Br) and coercive force (HC). In extreme cases, even if a drive current is applied to a coil to move one shaft type linear motor, the drive shaft of the linear motor to be driven should be moved under the influence of the permanent magnet of the adjacent linear motor. There is a problem that cannot be done. In addition, the position detection sensor that detects the strength of the magnetic field magnetized by the drive shaft described above is affected by the magnets of the adjacent linear motors, thereby causing a problem that accurate reading cannot be performed.

  For this reason, conventionally, it is necessary to arrange the linear motors with a sufficiently large distance between the linear motors so as not to cause an obstacle in control, and it is necessary to limit the number of nozzles provided in one mounting head. Or, since the mutual interval of the linear motors is increased, the mounting head is made larger than necessary.

  As described above, the present invention realizes reliable individual control of each linear motor without being adversely affected by the interaction of various magnets generated from each linear motor even when the distance between adjacent linear motors is made closer. And a multi-axis linear motor that can realize accurate position detection by a magnetic field detection sensor, a mounting head that uses the multi-axis linear motor, a component mounting apparatus, and a plurality of linear motors are arranged close to each other. However, it aims at providing the magnetic shielding method which does not receive the bad influence by a magnetic force mutually.

  In the present invention, the interaction between the linear motors constituting the multi-axis linear motor and the magnetic lines of the magnets or electromagnets of other linear motors adjacent to the magnetic lines of the magnets or electromagnets of the linear motors is provided between adjacent linear motors. The problem of the prior art is solved by providing magnetic shielding means for suppressing, and specifically includes the following contents.

Specifically, the mounting head and the component mounting apparatus according to the present invention are:
A plurality of nozzle portions for sucking parts; a negative pressure air supply portion for supplying negative pressure to the nozzle portions; and a multi-axis linear motor for moving the plurality of nozzle portions in the longitudinal direction, respectively. A component mounting mounting head and a component mounting apparatus for taking out components supplied to a component supply unit and mounting them at a mounting position on a circuit board,
The multi-axis linear motor is
A stator in which either permanent magnets or coils are linearly arranged;
And a movable part in which either a coil facing the permanent magnet of the stator or a permanent magnet facing the coil of the stator is linearly arranged, and the stator is energized by energizing the coil with a drive current A multi-axis linear motor provided with a plurality of shaft-type linear motors for moving the movable part with respect to
Magnetic shielding means for suppressing magnetic disturbance between the adjacent linear motors is further provided between the adjacent linear motors .

In another embodiment of the present invention, the linear motor is adjacent to the other linear motor only on one side, and there is no other linear motor on the other side that is axially symmetric with the one side. Further, magnetic force shielding means is further provided on the other side.

In another aspect of the present invention, when the plurality of linear motors are circumferentially arranged in a plane perpendicular to the longitudinal axis, the magnetic shielding means are arranged radially between the linear motors. It is characterized by.

According to another aspect of the present invention, each linear motor constituting the multi-axis linear motor detects the magnetic field strength of the driving permanent magnet provided on the driving shaft constituting the movable portion, thereby A position detection sensor unit for detecting the movement position of the drive shaft is further provided .

A component mounting apparatus according to another aspect of the present invention includes a plurality of the mounting heads that operate independently.

  By implementing the multi-axis linear motor including the magnetic shielding means according to the present invention, control failure and operation failure caused by the interaction of magnetic force between the linear motors can be avoided, and the multi-axis linear motor can be controlled smoothly as desired. Therefore, it is possible to operate the apparatus, and it is possible to avoid the occurrence of defects and the generation of defective products due to the operation of various facilities including the multi-axis linear motor, thereby improving the productivity and stabilizing the quality.

  Moreover, since it becomes possible to arrange a plurality of linear motors in close proximity, the multi-axis linear motor can be configured to be small and light.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a multi-axis linear motor provided with magnetic force shielding means according to the present invention and an apparatus using the multi-axis linear motor will be described below with reference to the drawings, taking a mounting head of a component mounting apparatus as an example. FIG. 1 shows an overall schematic perspective view of a component mounting apparatus 101 according to an embodiment of the present invention. The component mounting apparatus 101 includes a loader 1 that carries the circuit board 2 into the component mounting apparatus 101, an unloader 11 that can carry out the circuit board 2 on which the components are mounted from the component mounting apparatus 101, and the components on the circuit board 2. A first substrate transport and holding device 3 including a pair of support rail portions that transport and hold the circuit board 2 carried from the loader 1 while being mounted is provided.

  In FIG. 1, the circuit board 2-0 loaded on the loader 1 is carried into the component mounting apparatus 101, and the component is mounted on the circuit board 2-1 loaded on the first board transporting and holding apparatus 3. FIG. 6 also shows a state where the circuit board 2-3 on which the component is mounted is being unloaded from the component mounting apparatus 101 by the unloader 11. In the following description, “circuit board 2” is generally used when a circuit board is shown regardless of position, and “circuit board 2-0” is shown when a circuit board placed at a specific position is shown. , 2-1, 2-2, or 2-3 ". The same applies to the case where suffixes such as a, b, c,.

  The mounting apparatus main body 101 is further provided with a plurality of components that are respectively arranged at the end on the near side in the Y-axis direction of the drawing in the component mounting work area and that sequentially and sequentially supply the components mounted on the circuit board 2 to the component extraction position. A component supply unit 8A, 8B having a supply cassette 80 and a component supply unit 8C that is disposed in the vicinity of the component supply unit 8B and that stores components mounted on the circuit board 2 on a tray are provided. The components supplied from the respective component supply cassettes 80 in the component supply units 8A and 8B are, for example, mainly fine chip components, while the components supplied from the component supply unit 8C are, for example, main components. IC parts typified by an IC chip and irregular parts such as connectors.

  The mounting apparatus main body 101 further includes an attachment portion to which the component supply units 8A and 8B are attached, and a first mounting head 4 that sucks and mounts components supplied from the component supply units 8A, 8B, and 8C on the circuit board 2. The recognition camera 9 that images the suction posture of the parts held by the nozzle portion 39 provided at the tip of each suction nozzle assembly 10 provided in the first mounting head 4, and the entire mounting apparatus main body 101. And a mounting control device 100 that controls the operation.

  The first mounting head 4 is configured to be movable by an XY robot 5 that is positioned at predetermined positions in the X-axis direction and the Y-axis direction that are two orthogonal directions in the component mounting work area that is the upper surface of the component mounting apparatus 101. ing. The first mounting head 4 is provided with a plurality of, for example, twelve nozzle portions 39 for sucking and holding components in a releasable manner. The first mounting head 4 can move the component mounting work area two-dimensionally by the XY robot 5. For example, the first mounting head 4 is moved to the component supply positions of the component supply units 8A, 8B, and 8C to suck and hold the components supplied from the component supply units 8A, 8B, and 8C, respectively. A nozzle station for exchanging the nozzle unit 39 mounted on the mounting head 4 as necessary to a position facing the first substrate transport and holding device 3 for mounting components on the circuit board 2-1 held by 7 can be moved to positions facing each other. The nozzle station 7 is disposed in the vicinity of the component supply unit 8A in the component mounting work area, and stores a plurality of types of nozzle units 39 suitable for a plurality of types of components.

  The component mounting apparatus 101 shown in FIG. 1 further receives the circuit board 2-1 transferred from the first board transfer holding device 3 and performs the same component mounting operation on the back side in the Y direction in the figure, so that it has been described so far. Similar to the configuration, the apparatus includes a second substrate transport and holding device 13, a second mounting head 14, an XY robot 15, a nozzle station 17, component supply units 18A to 18C, and a recognition camera 19. Further, the load cell 12 for measuring the load when the nozzle portions 39 of the first mounting head 4 and the second mounting head 14 are in contact with each other and adjusting the height of the nozzle portion 39 is 2 in the component mounting work area. It is provided in the place.

  The component mounting apparatus 101 shown in the figure has two component mounting work areas arranged on the upper surface of the mounting apparatus base 16, and each of the first substrate transport holding apparatus 3 and the second substrate transport holding apparatus 13 has a structure. It is possible to perform component mounting operations simultaneously and independently on each held circuit board 2 using the first mounting head 4 and the second mounting head 14.

  FIG. 2 is a perspective view of the XY robots 5 and 15 used in the component mounting apparatus shown in FIG. As shown in FIG. 2, the XY robots 5 and 15 support the first mounting head 4 (not shown) so as to be movable in the X-axis direction of the drawing, and drive the movement of the first mounting head 4 in the X-axis direction. A first X-axis part 6b, a second X-axis part 6c that supports the second mounting head 14 so as to be movable in the X-axis direction shown in the figure, and drives the movement of the second mounting head 14 in the X-axis direction; 16 (see FIG. 1), is installed near the respective end portions in the X-axis direction, supports the respective X-axis portions 6b and 6c at the respective end portions, and the respective X-axis direction drive portions 6b and 6c. And a Y-axis part 6a for driving movement in the Y-axis direction shown in the figure.

  The Y-axis part 6a can drive the two X-axis parts 6b and 6c independently of each other in the Y-axis direction. That is, the first mounting head 4 can move in the X-axis direction or the Y-axis direction above the component mounting area on the front side in the figure by the X-axis portion 6b and the Y-axis portion 6a. On the other hand, the X-axis part 6c and the Y-axis part 6a allow the second mounting head 14 to move in the X-axis direction or the Y-axis direction above the component mounting area on the back side in the figure. The movement operations of the first and second mounting heads are independent of each other. Furthermore, both the X-axis parts 6b and 6c are limited in the range of movement in the Y-axis direction, and the occurrence of a mutual collision due to the respective movements is prevented. The XY robots 5 and 15 are configured to be able to move the first mounting head 4 and the second mounting head 14 in the XY directions using a linear motor, a ball screw, or the like as a drive source.

  In addition, as shown in FIG. 1, the component mounting apparatus 101 can perform overall control while associating the board loading / unloading, component holding, component recognition, component mounting operations, and the like with each other. A mounting control apparatus 100 is provided. The mounting control apparatus 100 includes respective component supply units 8A and 8B, 18A and 18B, a component supply cassette 80, first and second mounting heads 4 and 14, recognition cameras 9 and 19, and first and second substrate transports. The holding devices 3 and 13, the XY robots 5 and 15, the loader 1, and the unloader 11 are connected. The mounting control apparatus 100 includes a database unit and a memory unit. These include, for example, a library of component information related to the shape and height corresponding to the type of component, board information related to the shape and the like corresponding to the type of circuit board, and each type of nozzle corresponding to the type of component. NC data which is a mounting program such as the shape and nozzle position information of the part 39, which parts are mounted in which order and in which order, an arrangement program such as which parts are arranged in which part supply member, or the arrangement Arrangement information, information on the substrate conveyance position in each substrate conveyance holding device, and the like are stored so as to be removable.

  FIG. 3 shows a cross section of the X-axis portion 6. As shown in the figure, the X-axis portion 6 is provided with an X-axis linear motor shaft 32 on an X-axis frame 36 having a substantially Y-shaped cross-section, and X-axis linear guides 33 at two positions above and below. The X-axis linear motor shaft 32 is inserted into the X-axis movable part 34 of the mounting head movable part 31 and engages both. The mounting head movable portion 31 is configured to be movable in the X-axis direction along the two X-axis linear guides 33. The X-axis frame 36 is provided with an X-axis linear scale 38 so that the position of the mounting head movable unit 31 can be detected by an X-axis position sensor 37 provided on the mounting head movable unit 31. Yes. The mounting head movable unit 31 includes an attachment surface 35 that fixes the first or second mounting head 4 or 14. When a normal motor is used as an alternative to the linear motor for driving the X axis, a ball screw is generally used instead of the linear motor shaft 32.

  Next, the structure of the mounting heads 4 and 14 will be described with reference to the drawings. Since the first mounting head 4 and the second mounting head 14 have the same structure, the structure of the first mounting head 4 will be described as a representative in the following description. FIG. 4 shows an entire image of the mounting head 4, and FIGS.

  4, the mounting head 4 includes a plurality of, for example, twelve suction nozzle assemblies 10a to 101, and six rows are arranged at a constant pitch Px along the X-axis direction in the figure. Two rows are arranged at a constant interval pitch Py along the Y-axis direction. The mounting head 4 is configured using a so-called multi-axis linear motor. The respective suction nozzle assemblies 10 included in the mounting head 4 are referred to as first to sixth suction nozzle assemblies 10a to 10f in order from the front side in the Y-axis direction and the left side to the right in the X-axis direction. The seventh to twelfth suction nozzle assemblies 10g to 10l (only 10a, 10b, and 10f are shown in the drawing) in order from the rear side in the axial direction and from the left side to the right side in the X-axis direction. .

  In the component supply unit 8A (or 8B, see FIG. 1), a plurality of component supply cassettes 80 are arranged at a constant interval pitch L along the X-axis direction in the drawing. The fixed interval pitch Px in the array of the respective suction nozzle assemblies 10 may be a dimension (Px = L × n) that is an integral multiple of the fixed interval pitch L in the array of the component supply cassettes 80. In the present embodiment, the interval pitch Px of the suction nozzle assembly 10 and the interval pitch L of the component supply cassette 80 have the same dimension (n = 1). The first suction nozzle assembly 10a to the twelfth suction nozzle assembly 10l have substantially the same structure.

  Next, FIG. 5 shows a state in which the mounting head 4 shown in FIG. 4 is attached to the X-axis portion 6 shown in FIG. In FIG. 5, each suction nozzle assembly 10 (in FIG. 5, only the first suction nozzle assembly 10 a and the seventh nozzle assembly 10 g located on the front side are shown. Others appear behind them). The outer cylinder 53 including a housing 46 and a ball spline nut 53a provided above the mounting head 4 is movable in the Z-axis direction shown in the figure and is held rotatably about the same axis. The suction nozzle assembly 10 is configured to be vertically movable in the axial direction (Z-axis direction) by an actuator (linear motor) 40 provided in the housing 46 as will be described later. At the same time, the suction nozzle assembly 10 rotates around the axis. The spline shaft 44 is provided so that the θ rotation can be performed. Each suction nozzle assembly 10 includes a spline shaft 44, a nozzle portion 39 provided at the lower end of the spline shaft 44, a drive shaft 45 configured integrally with the spline shaft 44, and the suction nozzle assembly 10. And a timing pulley 41 for rotating.

  The drive shaft 45 functions as a drive shaft for the actuator 40 for moving the suction nozzle assembly 10 up and down. A timing pulley 41 is connected to the spline shaft 44, and both can move relative to each other in the Z-axis direction, and relative movement in the rotation direction around the Z-axis is restricted. The details are shown in FIG. 6 shows the relationship between the suction nozzle assembly 10, the timing pulley 41, and the timing belt 43 as seen from above. One timing belt 43 is engaged with each timing pulley 41 of the first to sixth suction nozzle assemblies 10a to 10f. The timing belt 43 is engaged through five tension pulleys 43a and 43b in order to completely engage the six suction nozzle assemblies 10a to 10f with the pulley 41, respectively. By the engagement of the timing belt 43, forward / reverse rotation driving of the θ rotation motor 42a is transmitted through the timing belt 43, and the first to sixth suction nozzle assemblies 10a to 10f are simultaneously rotated by θ (the suction nozzle group). It can be rotated around the axis of the solid 10).

  Similarly, different timing belts 43 are engaged with the respective timing pulleys 41 of the seventh to twelfth suction nozzle assemblies 10g to 10l, whereby the forward / reverse rotational driving force of another θ rotation motor 42b. Is transmitted through the timing belt 43, and the seventh to twelfth suction nozzle assemblies 10g to 10l can be simultaneously rotated by θ. Such a drive format by the two sets of timing belts 43 is merely an example.

  Returning to FIG. 5, the actuator 40 is constituted by a shaft type linear motor (hereinafter, this is indicated by reference numeral 40), and the corresponding nozzle portion 39 is moved up and down by the linear motor 40 to selectively perform the component suction operation. Alternatively, a component mounting operation is performed. Each of the component supply cassettes 80 accommodates components so that they can be removed, and has a component extraction position when the components are extracted. Further, the respective component take-out positions are arranged in a line at a constant interval pitch L in the X-axis direction as shown above. Thus, for example, the first suction nozzle assembly 10a is placed above the part removal position in the first part supply cassette 80, and the second suction nozzle assembly 10b is placed above the part removal position in the second part supply cassette 80 simultaneously. The nozzle portions 39 arranged in the X-axis direction can be arranged above the component supply cassettes 80 arranged in the X-axis direction as shown in FIG. It is possible to simultaneously pick up and remove parts from the position.

  Next, the linear motor 40 of the mounting heads 4 and 14 will be described with reference to the drawings. In FIG. 5, the linear motor 40 is provided in a drive shaft 45 configured coaxially with the spline shaft 44 of the suction nozzle assembly 10, a housing 46 of the mounting head 4, and includes a coil 48, a position detection magnetic pole sensor 49, and the like. And a stator 47 provided with. In the illustrated example, the stator 47 is provided with the position detection magnetic pole sensor 49 as described above. However, the sensor 49 may be separately provided outside the stator 47, which will be described later.

  The drive shaft 45 fixed to the first to sixth suction nozzle assemblies 10a to 10f (the right column of the two suction nozzle assemblies shown in FIG. 5) is configured to be hollow. By sucking air from the suction connection port 45b provided at the upper end, negative pressure air can be passed through the hollow hole 45e to the nozzle portion 39 provided at the tip of the drive shaft 45. . Further, the drive shaft 45 fixed to the seventh to twelfth suction nozzle assemblies 10g to 10l (the left column of the two suction nozzle assemblies shown in FIG. 5) is solid. The spline shaft 44 is provided with a suction port 45c for air suction. The suction port 45 c is connected to a suction connection nozzle 45 d provided in the outer cylinder 53, and sucks air in the spline shaft 44, thereby passing negative pressure air to the nozzle portion 39 provided at the tip of the spline shaft 44. It is configured to be able to.

  Each suction nozzle assembly 10 is configured to be moved up and down in the Z-axis direction by a linear motor 40, while being attached upward in the drawing by a spring 52 so that the suction nozzle assembly 10 is not lowered by gravity. Held in a biased state. That is, a spring seat 54 provided on the outer cylinder 53 side having a ball spline nut 53 a that receives the spline shaft 44 of each suction nozzle assembly 10, and a drive shaft 45 that is integrally formed with each spline shaft 44. Between the fixed spring seat 55, a spring 52 having a natural length longer than the distance between the two spring seats 54, 55 is disposed coaxially with the drive shaft 45 so that the drive shaft 45 is attached upward in the figure. The suction nozzle assembly 10 is configured not to fall due to gravity. The spring seat 55 also functions as a stopper that contacts the lower end of the stator 47 when the drive shaft is at the origin position and prevents the drive shaft from rising further.

  Next, the configuration of the linear motor 40 will be described with reference to FIG. The plurality of driving permanent magnets 45a constituting the driving shaft 45 are all cylindrical permanent magnets having substantially the same length, and both ends in the axial direction are magnetized to S and N poles. The driving permanent magnet 45a is concentrically stacked and fixed on the driving shaft 45 so that the S pole and the N pole face each other in the axial direction. The magnetic pole provided on the drive shaft 45 may be configured to be incorporated in the drive shaft using a plurality of cylindrical magnets having a uniform length, or a sheet-like permanent magnet may be used as the drive shaft. You may arrange | position and arrange | position on the outer peripheral surface. Alternatively, the drive shaft may be directly magnetized.

  The stator 47 is formed by laminating a plurality of ring-shaped coils 48 provided with a hollow circular hole into which the driving shaft 45 can be inserted at the center so that the holes are concentric and overlap in the Z-axis direction. 48 holes are formed as insertion holes for the drive shaft 45. The coil 48 is positioned in the stator 47 so as to face the permanent magnet 45a of the drive shaft 45 when the drive shaft 45 is received in the insertion hole. Specifically, the coil is wound in a loop around a member including a core portion for winding the coil so as to surround the outer peripheral surface of the driving permanent magnet 45a, and the coil faces the driving permanent magnet 45a. It is attached in the stator 47. In order to avoid contact between the coil 48 and the driving permanent magnet 45a, a protective film such as a polytetrafluoroethylene film is attached to the outer surface of the coil 48. Thus, the coil 48 is preferably arranged along the curved outer peripheral surface of the driving permanent magnet 45a in order to minimize the loss of magnetic field lines.

  Bearings 50a and 50b (see FIG. 5) are provided above and below the laminated coil 48 to guide the drive shaft 45 so as not to deviate from the axial center of the laminated coil 48, and to drive the shaft. 45 is held in a state where it can move in the axial direction. A pair of position detecting sensor units 49a and 49b are arranged further below the bearing 50b on the lower side of the figure. Each position detection magnetic pole sensor 49 includes a pair of magnetic pole detection sensors (491 and 492, or 493) arranged in the axial direction of the drive shaft 45 at intervals of 1/2 the length of one drive permanent magnet 45a. 494), so that when one of the magnetic pole sensors detects a substantially maximum magnetic field strength (that is, when it is at a position facing the axial tip of one driving permanent magnet 45a). The other magnetic pole detection sensor can detect a substantially zero magnetic field strength (that is, the center position in the axial direction of one driving permanent magnet 45a). The moving position of the drive shaft 45 can be detected from the change in the strength of the magnetic field output from the pair of magnetic pole detection sensors.

  The position detecting sensor unit 49 for detecting the driving magnetic pole of the driving shaft 45 is merely an example as described above, and other position detecting means may be provided. This will be described later.

  Next, in FIG. 8, the housing 46 has a hollow rectangular parallelepiped shape having a sufficient thickness for mechanical strength, and is made of a nonmagnetic material such as a plastic material, aluminum, or a ceramic material. The housing 46 has a through hole 56 on its upper surface that is slightly larger than the diameter of the drive shaft 45 so as to movably receive the drive shaft 45. The through hole 56 is aligned so as to communicate with a hollow hole provided in the coil of the stator 47 disposed in the housing 46. On the side surface of the housing 46, a female screw 57 for screwing to the mounting surface 35 (see FIG. 3) of the mounting head movable portion 31 is provided.

  The component mounting apparatus 101 configured as described above operates as follows. First, components are supplied to the component supply units 8A to 8C, and the mounting head 4 driven by the XY robot 5 moves to a position facing the component supply units 8A to 8C. The nozzle portion 39 is lowered by the operation of the mounting head 4 and comes into contact with the components. Then, the negative pressure air is supplied to suck the components and take out the components from each component supply cassette 80. By driving the XY robot 5, the mounting head 4 moves to a position facing the recognition camera 9, and the component suction state is imaged. The holding state of the component is analyzed based on the imaging result, and if the mounting control device 100 determines that the holding state is appropriate, the mounting head 4 further moves to a position facing the circuit board 2. During this movement, θ rotation is applied to the nozzle portion 39 based on the imaging result, and the angle of the held component is corrected. Thereafter, the mounting head 4 that has moved to a position facing the predetermined mounting position of the circuit board 2 lowers the nozzle portion 39 and mounts the held components at the mounting position. Each suction nozzle assembly 10 of the mounting head 4 performs the same operation to mount components, and the operations so far are repeated.

  In the present embodiment, a magnetic shielding member 60 shown in FIG. 5 is provided for the mounting head 4 according to the above-described configuration in order to avoid mutual interference due to magnetic force between adjacent linear motors 40. This content will be described in more detail with reference to FIGS. 9A to 9D. FIG. 9A is a front view showing a housing 46 portion of the mounting head 4 a provided with the magnetic shielding material 60. It can be seen that the linear motors 40 of the six suction nozzle assemblies are arranged in front from the window portion of the housing 46 (the six linear motors 40 in the second row appear behind them). In the mounting head 4a according to this aspect, the magnetic shielding materials 60 are arranged between the adjacent linear motors 40 and at a total of seven locations outside the two linear motors 40 at the left and right ends of the figure. In other words, all of the arranged shaft type linear motors 40 are provided with the magnetic shielding material 60 on both sides in the figure. Each magnetic shielding material 60 penetrates the housing 46 in the vertical direction of the drawing and is arranged in a direction perpendicular to the drawing. Each magnetic shielding member 60 is also fixed to the upper surface of the housing 46 by a mounting portion 61 bent in an L shape at the upper end, and the lower end is a position when the drive shaft 45 (not shown) of the linear motor 40 moves downward. It extends to.

  For the purpose of shielding only the interaction caused by the magnetic lines of force from the adjacent linear motors 40, it may be sufficient to provide the five magnetic shielding members 60 that are intermediate positions between the adjacent linear motors 40. However, if such a magnetic shielding material 60 is arranged, the magnetic lines of force generated by the magnets and electromagnets of the linear motor 40 located at both ends are not stable, and therefore it becomes difficult to control the linear motor 40. Regardless of the above, it is preferable that the magnetic shielding material 60 is similarly disposed outside the linear motor 40 at both ends.

  In the mounting head 4a shown in FIG. 9A, the position detecting sensor 49 for detecting the position of the driving shaft 45 of each linear motor 40 is not in the stator 47 of the linear motor 40, but in the driving shaft 45 at the upper side of the figure. Is provided at an extended position. A fan 65 visible on the left side of the figure is a cooling fan for forcibly introducing cooling air into an array of linear motors 40 to be described later.

  FIG. 9B shows a cross-sectional side view of the mounting head 4a shown in FIG. 9A. In the figure, the mounting head 4a is fixed to the mounting surface 35 of the mounting head movable portion 31, and in the state shown in the drawing, the two suction nozzle assemblies 10a and 10g on the front side of the first row and the second row are shown. Linear motors 40 are shown (the linear motors 40 of other suction nozzle assemblies 10 appear behind them). A large number of fins 40a are provided on both the left and right sides of the two linear motors 40 seen in the center to cool the heat generated by the linear motors 40. In particular, at the central part of both linear motors 40 that generate heat most easily, air is forcibly introduced by the above-described fan 65 (see FIG. 9A) in the direction perpendicular to the drawing to allow the cooling effect To increase.

  The magnetic shielding material 60 is represented as the width direction in FIG. 9B, whereas FIG. 9A is the thickness direction (a part of the magnetic shielding material 60 is indicated by a broken line in the figure). In this embodiment, the magnetic shielding material 60 is formed of an integral plate so that the suction nozzle assemblies 10 in the first row and the second row can be covered simultaneously. This will be described later.

  In the upper part of the drawing, a position detecting sensor 49 including a detected portion 59 extended through a flexible joint 58 is provided on the driving shaft 45 of the linear motor 40. In this example, the magnetic pole detection sensor 491 detects a continuous N pole and S pole that are finely magnetized in the axial direction of the detected portion 59, but optically detected by using a linear scale. It is also possible to use means to do so. The flexible joint 58 eliminates the need for exact alignment between the drive shaft 45 of the linear motor 40 and the detected portion 59, and facilitates assembly.

  In the embodiment shown in FIG. 5, since the magnetic pole for driving magnetized on the driving shaft 45 is detected by the magnetic pole detection sensor 491, the magnetic force of the detected portion is strong. It was desirable to shield the strong magnetic force from the adjacent linear motor 40 with the shielding material 60. In the example shown in FIG. 9B, since the position detection sensor 49 detects a relatively weak magnetic force dedicated to position detection, the influence of the magnetic force between the linear motors 40 is small, and the sensor unit is located outside the magnetic shielding material 60. Even if 49 is provided, no problem occurs. However, it is possible to cover the sensor unit 49 by extending the magnetic shielding material 60 as necessary.

  FIG. 9C shows the mounting head 4a according to this aspect as viewed from above. As is apparent from the figure, the total of seven magnetic shielding members 60 have the mounting portions 61 fixed at the upper portion of the housing 46 (the fasteners such as screws are omitted in the drawing). The two suction nozzle assemblies 10 in the row are covered and extend in the Y-axis direction in the figure. In the present embodiment, the interval pitch Py between the suction nozzle assemblies 10 in the first and second rows in the Y-axis direction is set wider than the interval pitch Px in the same arrangement in the X-axis direction. (Py> Px). As a result, control of each shaft type linear motor 40 is not hindered even if the magnetic shielding material 60 is not provided between the suction nozzle assemblies 10 in the Y-axis direction in the figure. However, if necessary in the Y-axis direction, a similar magnetic shielding material 60 can be provided. Note that a cooling fan 65 for forcibly circulating air between the linear motor 40 described above and cooling is seen on the lower side of the figure.

  FIG. 9D shows a specific example of the magnetic shielding material 60 used in this embodiment. In the figure, the magnetic shielding material 60 is preferably formed of a ferromagnetic material such as an iron plate, for example. However, the invention is not limited to this, and other materials may be used as long as they can shield the lines of magnetic force. In the example shown in the figure, an example that can be easily made by punching and bending an iron plate is shown. A mounting portion 61 formed by bending in an L shape is provided on the upper portion, and a fixing screw 64 is inserted into a fastening hole 63 of the mounting portion 61 and fixed to the upper end of the housing 46 of the mounting head 4a.

  The long hole 62 provided in the central portion of the magnetic shielding material 60 allows air to pass when blowing cooling air that passes through the X-axis direction of the mounting head 4a and cools the heat generated by the linear motor 40. It is a hole. When the linear motors 40 are not arranged in two rows in the Y-axis direction, the long holes 62 are not necessary.

  When the magnetic shielding material 60 as described above is provided, magnetic lines generated from the magnet of the linear motor 40 on one side of the magnetic shielding material 60 are generated from the magnet of the linear motor 40 on the other adjacent side. As a result of suppressing the interaction with the magnetic field lines, each magnetic field line is formed as a closed loop magnetic field line connected to the magnet of its own motor. For this reason, it is avoided that the linear motors 40 are adversely affected by each other's magnets, and the control and operation of the linear motor 40 are not hindered.

  According to the experiments conducted by the inventors of the present application, the linear motor 40 that did not operate at all even when the drive current was supplied to the coil 48 was simply inserted a single iron plate between the adjacent linear motors 40. In most cases, it was possible to operate without any problem, and a very remarkable effect was recognized. The thickness of the iron plate varies depending on the specifications such as the strength of the magnetic force of each magnet, but a sufficient effect is recognized even when the thickness is about several millimeters of comma, for example. In addition, the steel plate as used in this specification includes a steel plate.

  FIGS. 10A to 10D show examples of arrangement of the magnetic shielding material 60 when a plurality of linear motors 40 are arranged in various forms. In each of the drawings, the linear motor 40 is viewed from the axial direction, and in FIG. 10A, the linear motor 40 is circumferentially arranged in a plane perpendicular to the axis. In such a form, the magnetic shielding material 60 can be arranged radially in the middle of each of the plurality of linear motors 40. In this case, the arrangement of the pair of magnetic shielding members 60 arranged on both sides of the one linear motor 40 is not parallel to each other, and is radially directed toward the center of the circle and has a constant angle with each other. Inclined state. However, even in the case of such an arrangement, the effect of shielding the lines of magnetic force can be obtained without any problem as long as the inclination is to some extent. The degree of inclination that can be achieved varies depending on the specifications of the linear motor 40 and the interval between the linear motors 40, and cannot be generally stated. In FIG. 10A, the arrangement of the linear motors 40 is a circular shape. However, for example, a plurality of linear motors 40 such as an ellipse and an ellipse are generally arranged adjacent to each other in a circular manner with their axes substantially parallel. In such a case, similarly, the magnetic shielding material 60 can be disposed between the adjacent linear motors 40 to avoid the mutual influence due to the magnetic lines of force.

  FIG. 10B shows a case where a plurality of linear motors 40 are arranged in a grid pattern so as to approach each other in two orthogonal directions. In this case, the magnetic shielding material 60 may be disposed between the linear motors 40 adjacent in the vertical and horizontal directions. As shown in the drawing, when the distance between the linear motors 40 is the same in two orthogonal directions, the magnetic shielding material 60 is arranged in a square shape. Note that the linear motors 40 positioned at the terminals of each array are not adjacent to the other linear motors 40 on at least one side, but it is also possible to similarly provide the magnetic shielding material 60 on the non-adjacent side. This is desirable for correct control.

  FIG. 10C shows a case where a plurality of linear motors 40 are arranged in a staggered manner. In such a state, the influence of mutual magnetic lines of force can be avoided by forming the magnetic shielding material 60 in a cylindrical shape so as to surround the periphery of the linear motor 40. In the radial arrangement shown in FIG. 10 (a), even when the magnetic shielding material 60 has an excessively large inclination between the magnetic shielding materials 60, a magnetic shielding effect cannot be obtained sufficiently, as shown in FIG. 10 (c). It can be solved by surrounding with the magnetic shielding material 60.

  Next, FIGS. 11A to 11C show the magnetic shielding material 60 as described so far in advance according to the arrangement state of the linear motor 40 without considering the arrangement state separately in advance. An embodiment is shown in which a unit type linear motor is formed integrally with the motor 40 and has a magnetic shielding effect.

  FIG. 11A shows a unit-type linear motor 401 in which a pair of magnetic shielding materials 60 that are opposed to each other with the linear motor 40 interposed therebetween are integrally formed on the outer periphery of the linear motor 40. A driving shaft 45 is arranged at the center so as to be movable in the axial direction which is the upper and lower sides of the drawing, and a stator 47 including a driving coil 48 (not shown) is surrounded around the shaft. In the illustrated example, the pair of magnetic shielding materials 60 are fixed to a non-magnetic material (for example, plastic) that encloses the stator 47, and are integrally formed. Various methods such as adhesion, integral molding with a plastic material that wraps the coil 48, and clip fastening in the vertical direction are conceivable as a method for fixing the both. Such a unit type linear motor 401 is formed integrally when the linear motor 40 is arranged close to only in one axial direction such as the mounting heads 4 and 14 shown in the present embodiment. The linear motor 40 can be disposed and used with the magnetic shielding materials 60 facing each other. In the example shown in the figure, a pair of opposing magnetic shielding materials 60 formed integrally are arranged in parallel. However, as shown in FIG. 10A, the magnetic shielding materials 60 are arranged radially. Then, it is also possible to arrange them at an angle with respect to each other rather than in parallel.

  FIG. 11B shows a unit type linear motor 402 in which the magnetic shielding material 60 is arranged in four directions along the longitudinal axis of the linear motor 40. In this example, a casing 51 made of a non-magnetic material (for example, plastic) having a substantially rectangular cross section is provided around the linear motor 40, and the magnetic shielding material 60 is arranged in four directions with respect to the casing 51. Other configurations are the same as those shown in FIG. In the illustrated example, the magnetic shielding material 60 is arranged in a substantially square shape when viewed in cross section, but may be arranged in a rectangular shape according to the vertical and horizontal intervals between the linear motors 40. Alternatively, it may be a trapezoidal shape, a rhombus or other irregular quadrilateral cross-section that is deformed to some extent from a rectangle. The integrated linear motor 402 having such a configuration can be used when the linear motor 40 as shown in FIG.

  FIG. 11C shows an example in which the magnetic shielding material 60 is formed in a cylindrical shape on the outer periphery of the linear motor 40. The other configuration is the same as that shown in FIG. 11B except that the magnetic shielding material 60 has a cylindrical shape and the casing 51 has a columnar shape. By forming such a unit-type linear motor 403, it can be used, for example, when the linear motors 40 as shown in FIG. Further, when the magnetic shielding materials 60 as shown in FIG. 10A are arranged radially, the inclination angle between the magnetic shielding materials 60 on both sides of each linear motor 40 is too large, and a sufficient magnetic shielding effect is obtained. It can be used even when it is not possible. In addition, the cross-sectional shape of the magnetic shielding material 60 is not necessarily a circle, and may be another shape such as an ellipse or an ellipse depending on the purpose. Alternatively, the magnetic shielding material 60 surrounding the four sides shown in FIG. 11B can be formed so as to be surrounded by a hollow square member having a quadrilateral cross section.

  11A to 11C, the length of the magnetic shielding material 60 in the longitudinal direction is drawn in accordance with the length of the stator 47, but this is for illustrative purposes and driving. When the magnetized portion of the shaft 45 is longer than this, it is preferable that the magnetic shielding material 60 has a length that wraps it over the entire range in which the magnetized portion strokes.

  In the embodiments described so far, it is assumed that the interaction due to the magnetic force lines between the plurality of linear motors 40 is avoided. However, the cylindrical magnetic shielding material 60 shown in FIGS. In the linear motors 401 to 403 formed integrally with each other, a unique effect can be obtained even when used alone. For example, in the environment where a linear motor is used in various devices, other components including ferromagnetic materials and magnets such as actuators and transfer devices pass through the proximity distance of the linear motor, or are fixedly arranged close to each other. It can be done. In such a case, these equipment components may affect the magnetic lines of the magnets and electromagnets constituting the linear motor 40 and cause unexpected control failures and operation failures. The linear motors 401 to 403 integrally formed with the illustrated magnetic shielding material 60 can suppress the spread of magnetic lines of force generated by magnets and coils to the outside, and are used in an environment in which the above-described obstacles may occur. Even in such a case, it is possible to eliminate magnetic disturbance and ensure smooth control and operation. Conversely, the effect of preventing adverse effects on surrounding electronic devices due to electromagnetic waves generated in the coils 48 of the linear motors 401 to 403 can also be obtained.

  As mentioned above, although the shaft type linear motor concerning this invention and the application of this linear motor were described, this invention is not limited to the application to embodiment described so far. For example, the application to the mounting head of the component mounting apparatus described in the embodiment is merely an example, and can be similarly applied to a multi-axis actuator having a plurality of linear motors used for various other purposes. It is. Also, in the component mounting apparatus, in the embodiment, an example of a type having two mounting heads that operate independently is taken as an example, but one mounting head or three that operate independently are used. The thing of the type provided with the above mounting head may be sufficient. Furthermore, the present invention is not limited to the XY robot type, but also for a rotary type component mounting apparatus that mounts a plurality of suction nozzle assemblies circumferentially and mounts components using an indexing disk that rotates intermittently. Applicable. In this specification, this index is also included in the concept of the robot for transport.

1 is an overall schematic perspective view of a component mounting apparatus according to an embodiment of the present invention. It is a perspective view which shows schematic structure of the XY robot of the component mounting apparatus shown in FIG. It is a side view of the X-axis part of the XY robot shown in FIG. It is a perspective view which shows the external appearance structure of the mounting head of the component mounting apparatus shown in FIG. FIG. 5 is a cross-sectional view in the Y direction of the mounting head shown in FIG. 4. 5 is a θ rotation mechanism of the suction nozzle assembly of the mounting head shown in FIG. 4. FIG. 5 is a partially enlarged sectional view of a linear motor included in the mounting head shown in FIG. 4. FIG. 5 is a partially enlarged perspective view of the first mounting head shown in FIG. 4. It is a front view which shows the mounting head concerning embodiment of this invention. It is side surface sectional drawing of the mounting head shown to FIG. 9A. FIG. 9B is a plan view of the mounting head shown in FIG. 9A. It is a perspective view of the magnetic shielding material used for the mounting head shown in FIG. 9A. It is explanatory drawing which shows the arrangement | positioning state of the magnetic shielding material of the other aspect concerning this invention. It is a perspective view which shows the unit type linear motor of the further another aspect concerning this invention.

Explanation of symbols

4). First mounting head, 10. 14. suction nozzle assembly; Second mounting head, 31. Mounting head movable part, 35. Mounting surface, 39. Nozzle part, 40. Linear motor (actuator), 44. Spline shaft, 45. Drive shaft, 45a. Permanent magnet for driving, 46. Housing, 47. Stator, 48. Coils 50a, 50b. Bearings, 51. Casing, 53. Outer cylinder, 53a. Ball spline nut, 58. Flexible joint, 60. Magnetic shielding material, 61. Attachment part, 62. Slotted hole 63. Fastening hole, 64. Screw (fastening material), 100. Mounting control device, 101. Component mounting equipment.

Claims (6)

A plurality of nozzle portions for sucking parts; a negative pressure air supply portion for supplying negative pressure to the nozzle portions; and a multi-axis linear motor for moving the plurality of nozzle portions in the longitudinal direction, respectively. A mounting head for component mounting that takes out the component supplied to the component supply unit and mounts it on the mounting position of the circuit board,
The multi-axis linear motor is
A stator in which either permanent magnets or coils are linearly arranged;
And a movable part in which either a coil facing the permanent magnet of the stator or a permanent magnet facing the coil of the stator is linearly arranged, and the stator is energized by energizing the coil with a drive current A multi-axis linear motor provided with a plurality of shaft-type linear motors for moving the movable part with respect to
Magnetic shielding means for suppressing magnetic disturbance between adjacent linear motors between the adjacent linear motors ;
A casing means made of a non-magnetic material having a substantially rectangular cross section or a substantially circular cross section around the linear motor;
A mounting head characterized in that a unit-type linear motor is formed by arranging the magnetic shielding means with respect to the casing means . A plurality of nozzle portions for sucking parts; a negative pressure air supply portion for supplying negative pressure to the nozzle portions; and a multi-axis linear motor for moving the plurality of nozzle portions in the longitudinal direction, respectively. A mounting head for component mounting that takes out the component supplied to the component supply unit and mounts it on the mounting position of the circuit board,
The multi-axis linear motor is
A stator in which either permanent magnets or coils are linearly arranged;
And a movable part in which either a coil facing the permanent magnet of the stator or a permanent magnet facing the coil of the stator is linearly arranged, and the stator is energized by energizing the coil with a drive current A multi-axis linear motor provided with a plurality of shaft-type linear motors for moving the movable part with respect to
A plate-like magnetic shielding means for suppressing magnetic disturbance between the adjacent linear motors between the adjacent linear motors;
When the linear motor is adjacent to the other linear motor only on one side and there is no other linear motor on the other side that is axisymmetric with the one side, the magnetic force is also applied to the other side. implementation head characterized by further comprising a shielding means. The mounting head according to claim 1, wherein a hole through which air passes is provided in the magnetic shielding means .   Each linear motor constituting the multi-axis linear motor detects the moving position of the driving shaft by detecting the strength of the magnetic field of the driving permanent magnet provided on the driving shaft constituting the movable part. The mounting head according to claim 1, further comprising a position detection sensor unit. A component supply unit that continuously supplies components, a mounting head that picks up components from the component supply unit and mounts them on a circuit board, a robot that transports the mounting head, and a substrate transfer holder that carries and holds the circuit board The apparatus includes a device and a mounting control device that controls the entire operation. The component is taken out from the component supply unit using a nozzle unit mounted on the mounting head, and the component is mounted at a mounting position on the circuit board. A component mounting apparatus,
The component mounting apparatus according to claim 1, wherein the mounting head is the mounting head according to claim 1.   The component mounting apparatus according to claim 5, comprising a plurality of the mounting heads that operate independently.

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