JP2006147640A - Component mounting apparatus and component mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a component mounting device and a mounting method for shortening a tact time by reducing a tact time by reducing a weight of a driving part and suppressing an impact at the time of contact without reducing a lifting speed.
A component mounting apparatus has two motors for controlling the position of a component P in the height direction and a load to be pressed against an object to be mounted S. A small VCM 30 is mounted on a head unit 37 that is driven up and down by a servo motor 33. Is arranged. The small VCM 30 is configured to drive the sub head unit 31 in which the nozzle 28 is disposed up and down, and switches the operation of the servo motor 33 and the small VCM 30 with respect to a target load that presses the component P against the mounted object S.
[Selection] Figure 2

Description

  The present invention relates to a component mounting apparatus and a component mounting method for mounting a component on an object to be mounted.

  Conventionally, as a component mounting apparatus and a component mounting method, there are a component mounting control method and an apparatus using an air cylinder for pressing a component (see, for example, Patent Document 1). Hereinafter, a conventional component mounting control method will be described with reference to FIG. FIG. 14 is a schematic diagram showing a component mounting head controlled by the component mounting control apparatus described in Patent Document 1.

  In FIG. 14, the component mounting head controlled by the conventional component mounting control device is intended to mount the component P on the mounted object S in a predetermined pressing state. The component mounting head includes a servo motor 3 that is a lifting and lowering unit, a nozzle 4 that is a component holding unit, a force sensor 5 that detects a load on the component, and an air cylinder 6 that is a pressure control unit.

  The rotation shaft of the servo motor 3 is connected to the ball screw shaft 8. The ball screw shaft 8 is screwed with the nut portion 9 of the frame 20. The frame 20 supports the force sensor 5 and the air cylinder 6. The air cylinder 6 performs a pressing pressure control operation by the nozzle 4 supported via the block unit 19. That is, the frame 20, the air cylinder 6, the force sensor 5, the block unit 19, and the nozzle 4 are entirely moved up and down by the driving force of the servo motor 3. The block unit 19 and the nozzle 4 are moved up and down by the air pressure control operation of the air cylinder 6.

For example, the servo motor 3 lowers the component P held by the nozzle 4 at the maximum speed, decelerates the component P to a minimum speed at a predetermined position, and changes the load value of the force sensor 5 between the component P and the workpiece S. Detect contact. After the contact is detected, the air cylinder 6 is pressed so that the load value of the force sensor 5 becomes a predetermined load state. When the pressing is completed, the nozzle 4 releases the holding of the component P and rises to a predetermined position by the driving force of the servo motor 3. The component P is mounted on the mounted object S by a series of these operations. In this way, when the servo motor 3 lowers the component P toward the workpiece S, the servo motor 3 decelerates the descending speed from the maximum speed to the minimum speed at a predetermined height, so that the component P becomes the workpiece S. The impact when touching is suppressed.
JP 2001-210995 A

  However, since the conventional component mounting head uses the air cylinder 6 as the pressure control means, the response in detecting contact between the component P and the mounted object S is poor. Further, since the air cylinder 6 is used, the unit mass of the entire component mounting head is increased. Thus, in order to accurately perform contact detection while suppressing the impact at the time of contact between the component P and the workpiece S, the descending speed of the component mounting head is switched from the highest speed to the lowest speed before the contact. It is necessary to raise and lower the component mounting head, resulting in a longer tact time in the mounting operation.

  Therefore, an object of the present invention is to provide a component mounting apparatus and a mounting method that reduce the tact time by reducing the driving portion and reducing contact speed without reducing the ascending / descending speed while suppressing the impact at the time of contact. is there.

In order to achieve the above object, the present invention has the following features.
The component mounting apparatus of the present invention mounts a component on an object to be mounted. The component mounting apparatus includes a holding unit, a support member, a first motor, a sub head unit, a second motor, and a control unit. The holding unit holds the component. The first motor moves the support member up and down. The sub head unit is provided with a holding portion at the tip thereof. The second motor is provided on the support member and moves the sub head unit up and down. The control unit drives at least one of the first motor and the second motor to control the height direction position of the component held by the holding unit and the load that presses the component against the mounted object.

  In the component mounting method of the present invention, the component is mounted on the mounted object. The component mounting method includes a step of holding a component, a step of raising and lowering a support member, a step of selecting a motor, and a step of controlling a load. In the step of holding the component, the component is held by the holding unit. The step of raising and lowering the support member raises and lowers the support member that supports the second motor that raises and lowers the sub head unit provided with the holding portion at the tip by driving the first motor. When the step of selecting the motor and pressing the component held by the holding portion against the mounted object, the motor is selected as a motor that drives at least one of the first motor and the second motor according to the target load. The step of controlling the load drives at least one of the selected first motor and second motor to control the position in the height direction of the component held in the holding portion and the load that presses the component against the mounted object. To do.

  According to the component mounting apparatus and the component mounting method of the present invention, the impact at the time of contact between the mounted component and the mounted object can be suppressed by reducing the weight of the drive part. Thus, the tact time required for mounting can be shortened by increasing the speed at the time of contact detection.

  In addition, when a low load that is equal to or less than the maximum thrust of the second motor is targeted, the tact time can be further shortened because the component and the mounted object can be brought into contact with each other at a relatively high speed.

  Further, when the load to be pressed is directly detected, feedback control is possible, and the load can be controlled using a more accurate load value.

(First embodiment)
Hereinafter, a component mounting apparatus and a component mounting method according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the overall configuration of the component mounting apparatus.

  In FIG. 1, the component mounting apparatus includes a component mounting head unit 1, a moving table unit 22, a component supply unit 23, an XY robot unit 25, and a control device 26. The component mounting head unit 1 is mounted on the XY robot unit 25 and holds a component P (the component P includes a chip component such as an IC, a transistor and a memory, a semiconductor component such as a flip chip and a bare chip). The object is mounted on an object S (the object S includes a substrate, a wafer, etc.). As an example, the component mounting apparatus of the present invention is an electronic component mounting apparatus that mounts an electronic component on a mounting substrate. In this case, the component mounting head unit 1 holds the electronic component and mounts it on the mounting substrate. The detailed structure of the component mounting head unit 1 will be described later. The moving table unit 22 transports the mounted object S from the loading of the mounted object S to the unloading of the mounted object S, and holds the mounted object S in a predetermined position when the component P is mounted. The component supply unit 23 supplies the component P. The XY robot unit 25 moves and positions the component mounting head unit 1 to an arbitrary position on the moving table unit 22 in the X and Y directions (see FIG. 1) perpendicular to each other on a plane. The control device 26 controls operations of the component mounting head unit 1, the moving table unit 22, the component supply unit 23, and the XY robot unit 25.

  In addition, although the components supply part 23 has shown the form which supplies the components P with the components supply tray 27 which mounts the components P in a grid | lattice form in FIG. 1, it is not limited to this form, Other component supply devices such as a configuration in which the component P is supplied using a card ridge wound with a temporarily fixed tape may be used. In addition, the XY robot unit 25 shows a mode of moving in the X and Y directions in order to move the component mounting head unit 1 to an arbitrary position on the moving table unit 22, but is not limited to this mode. Alternatively, some functions of the XY robot unit 25 may be provided on the moving table unit 22 side. For example, an XY robot structure capable of moving the component mounting head unit 1 to an arbitrary position on the moving table unit 22 is used, for example, a moving function in one direction (for example, the X direction) is provided on the moving table unit 22 side. It doesn't matter. In addition, since the movement table part 22, the component supply part 23, and the XY robot part 25 are apparatuses conventionally used, detailed description beyond this is abbreviate | omitted here.

  Next, the structure of the component mounting head unit 1 will be described with reference to FIG. FIG. 2 is a schematic diagram showing the configuration of the component mounting head unit 1a according to the first embodiment.

  In FIG. 2, the component mounting head portion 1a includes a nozzle 28, a pressure shaft 29, a small VCM (voice coil motor) 30, a ball screw 32, a servo motor 33, an encoder 34, and a rotary shaft servo motor. 35, a rotary shaft encoder 36, a head unit 37, a block 38, bearings 39, 42 and 43, and a rotary shaft 41.

  The nozzle 28 holds the component P at its tip and corresponds to the holding portion of the present invention. For example, the nozzle 28 holds the component P by air pressure (negative pressure), and air pressure is passed through a suction passage (not shown) provided in a block 38 located between the nozzle 28 and the pressure shaft 29. When the change is transmitted, the component P held at the tip is removed. The pressure shaft 29 is disposed above the central axis of the nozzle 28 via the block 38 and supports the nozzle 28 and the block 38. The small VCM 30 is disposed on the central axis of the pressure shaft 29 and drives the mover 30a with a low output in the thickness direction of the component (the central axis direction). The thickness direction is a Z direction perpendicular to the X and Y directions in which the XY robot unit 25 can move. And the pressurization shaft 29 attached to the needle | mover 30a is raised / lowered in the thickness direction with the driving force of small VCM30. The ball screw 32 is disposed with the Z direction as an axial direction, and is connected to the rotation shaft of the servo motor 33. The encoder 34 detects the rotation amount and rotation speed of the servo motor 33. The rotary shaft servomotor 35 and the rotary shaft encoder 36 rotate the pressure shaft 29 about the central axis of the pressure shaft 29 via the rotary shaft 41 to rotate the part P held by the nozzle 28 to the part P. Position in the direction of rotation. The rotary shaft servomotor 35 is connected to the pressure shaft 29 via a guide (not shown) of the rotary shaft 41 extending in the Z direction, so that the small VCM 30 and the servomotor 33 operate. The rotary shaft servomotor 35 does not move in the Z direction. The head unit 37 has a nut portion 40 that is screwed with the ball screw 32, and moves up and down in the Z direction when the ball screw 32 is rotated by the drive of the servo motor 33. The head unit 37 is provided with a small VCM 30 and bearings 42, 43. When the small VCM 30 is driven, the pressure shaft 29 moves up and down with respect to the head unit 37 in the Z direction. The servo motor 33 corresponds to the first motor of the present invention, and the small VCM 30 corresponds to the second motor of the present invention.

  The pressurizing shaft 29 is supported by bearings 39, 42, and 43 in the rotating operation by the rotary shaft servomotor 35 and the elevating operation in the Z direction by the small VCM 30. Specifically, the pressure shaft 29 is attached to the mover 30a of the small VCM 30 via the bearing 39, and the mover 30a does not rotate even if the pressure shaft 29 rotates. The pressure shaft 29 is penetrated by bearings 42 and 43 attached to the head unit 37 and is supported so as to be movable in the Z direction. The sub head unit 31 is constituted by the nozzle 28 that moves up and down in the Z direction, the pressure shaft 29, the mover 30 a of the small VCM 30, the block 38, and the bearing 39 by the small VCM 30.

  Next, the configuration of the control device 26 will be described with reference to FIGS. 1 and 3. FIG. 3 is a block diagram showing the configuration of the control device 26.

  1 and 3, the control device 26 includes a component mounting head control unit 26a, a moving table control unit 26b, a component supply control unit 26c, an XY robot control unit 26d, and a host control unit 26e. The component mounting head control unit 26a is electrically connected to the component mounting head unit 1a and controls the operation of the component mounting head unit 1a. The movement table control unit 26 b is electrically connected to the movement table unit 22 and controls the operation of the movement table unit 22. The component supply control unit 26 c is electrically connected to the component supply unit 23 and controls the operation of the component supply unit 23. The XY robot control unit 26d is electrically connected to the XY robot unit 25 and controls the operation of the XY robot unit 25 in the X and Y directions. The host control unit 26e controls the overall operation of the component mounting apparatus by controlling the component mounting head control unit 26a, the moving table control unit 26b, the component supply control unit 26c, and the XY robot control unit 26d.

  Here, the component mounting head control unit 26a will be described. The component mounting head control unit 26 a includes a small VCM control unit 261, a servo motor control unit 262, and a rotary shaft servo motor control unit 263. The host control unit 26e sends positioning and weighting operation commands to the small VCM control unit 261, the servo motor control unit 262, and the rotary shaft servo motor control unit 263, respectively. The small VCM control unit 261 is electrically connected to the small VCM 30 and controls driving of the small VCM 30 based on an instruction from the host control unit 26e. The servo motor control unit 262 is electrically connected to the servo motor 33 and the encoder 34, and based on the rotation amount and rotation speed information of the servo motor 33 output from the encoder 34 and an instruction from the host control unit 26e, The drive of the servo motor 33 is controlled. Details of the control contents of the small VCM control unit 261 and the servo motor control unit 262 will be described later. The rotation axis servo motor control unit 263 is electrically connected to the rotation axis servo motor 35 and the rotation axis encoder 36, and the rotation amount and rotation speed of the rotation axis servo motor 35 output from the rotation axis encoder 36. Based on this information and an instruction from the host control unit 26e, the drive of the rotary shaft servomotor 35 is controlled. Note that the control content of the rotary shaft servomotor control unit 263 is the same as that of a conventionally used position control method, and thus detailed description thereof is omitted.

  Next, the small VCM control unit 261 will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of the small VCM control unit 261 and the host control unit 26e.

  In FIG. 4, the small VCM control unit 261 includes a weight command unit 261a, a weight control unit 261b, and a power amplifier 261c. The host control unit 26e includes a low-load operation command unit 26e1 and a high-load operation command unit 26e2 as components related to the small VCM control unit 261.

  When the component P is mounted, the weight command unit 261a receives a low load operation command from the low load operation command unit 26e1 of the host control unit 26e or a high load operation command from the high load operation command unit 26e2. Then, the weight command unit 261a outputs the weight command to the weight command unit 261b based on the low load operation command or the high load operation command. The weight control unit 261b outputs a torque control command to the power amplifier 261c based on the weight command from the weight command unit 261a. The power amplifier 261c drives the small VCM 30 with an input current based on the torque control command. Here, the torque control means that the input current to the motor is controlled so that the torque (force or rotational force) of the motor by driving becomes a torque based on the command. For example, in the case of a motor that directly outputs thrust, such as a VCM, although there is a sliding resistance loss in the guide or the like, the torque can be handled as it is as a load. In this case, the input current to the motor (VCM) and the load are in a proportional relationship, and the load due to motor driving can be controlled by controlling the input current by torque control.

  Next, the servo motor control unit 262 will be described with reference to FIG. FIG. 5 is a block diagram showing the configuration of the servo motor control unit 262 and the host control unit 26e.

  The servo motor control unit 262 includes a position / weight command unit 262a, a load control unit 262b, a position control unit 262c, a contact detection unit 262d, a speed control unit 262e, a switching unit 262f, and a power amplifier 262g. The host control unit 26e has a low load operation command unit 26e1 and a high load operation command unit 26e2 as components related to the servo motor control unit 262.

  When the component P is mounted, the position / weight command unit 262a receives a low load operation command from the low load operation command unit 26e1 of the host control unit 26e or a high load operation command from the high load operation command unit 26e2. Then, the position / weight command unit 262a outputs the weight command to the weight command unit 262b or the position command to the position control unit 262c based on the low load operation command or the high load operation command. The position / weight command unit 262a outputs a control switching signal to the contact detection unit 262d based on the low load operation command or the high load operation command.

  When performing torque control, based on the weighting command output from the position / weighting command unit 262a, the weighting control unit 262b outputs a torque control command to the power amplifier 262g via the switching unit 262f. The power amplifier 262g drives the servo motor 33 with an input current based on the torque control command. In the torque control, the contact detection unit 262d determines the torque from the weight control unit 262b based on the contact status between the component P to be mounted and the mounted object S and the control switching signal from the position / weight command unit 262a. The switching unit 262f is switched so that the control command is output to the power amplifier 262g.

  When position control to be described later is performed, the position control unit 262c outputs a speed command to the speed control unit 262e based on the position command output from the position / weight command unit 262a and the position information output from the encoder 34. Then, the speed control unit 262e outputs a position control command to the power amplifier 262g via the switching unit 262f based on the speed command and the speed information output from the encoder 34. The power amplifier 262g drives the servo motor 33 with an input current based on the position control command. Here, the position control is to control the input current to the motor so that the driven body (for example, the nozzle 28) driven by the motor moves at a speed based on the command and is arranged at the position based on the command. Is meant to do. In the position control, the contact detection unit 262d detects the position from the speed control unit 262e based on the contact state between the component P to be mounted and the mounted object S and the control switching signal from the position / weight command unit 262a. The switching unit 262f is switched so that the control command is output to the power amplifier 262g. As described above, the servo motor control unit 262 can control the operation of the servo motor 33 by either the torque control or the position control in accordance with an instruction from the host control unit 26e.

  Next, a specific example in which the control device 26 controls the operation of the component mounting head unit 1a will be described with reference to FIGS. FIG. 6 is a diagram illustrating a specific example in which the control device 26 controls the operation of the component mounting head unit 1a when mounting the component P with a low load. FIG. 7 is a diagram illustrating a specific example in which the control device 26 controls the operation of the component mounting head unit 1a when mounting the component P with a high load. Here, in FIG. 6 and FIG. 7, the first motor indicates the servo motor 33, and the second motor indicates the small VCM 30.

  The host control unit 26e of the control device 26 selects whether to operate the small VCM 30 and the servo motor 33 with a low load or a high load according to a target load for pressing the component P to be mounted against the mounted object S. To do. When the target load is less than or equal to the threshold value, the upper control unit 26e transmits a low load operation command to the small VCM control unit 261 and the servo motor control unit 262, respectively. In addition, when the target load is larger than the threshold value, the upper control unit 26e transmits a high load operation command to the small VCM control unit 261 and the servo motor control unit 262, respectively.

  The threshold value for selecting one of the low load operation and the high load operation by the host control unit 26e is set to a value equal to or less than the maximum thrust set in the small VCM 30. For example, a maximum thrust set for the small VCM 30, a value obtained by multiplying the maximum thrust by a predetermined safety factor, or a rated thrust set for the small VCM 30 may be used as the threshold. Specifically, it is assumed that the small VCM 30 is set to a rated current of 1 A and a thrust constant of 12 N / A, and the servo motor 33 has a rated current of 2.5 A and a thrust constant of 200 N / A. In this case, the rated thrust of the small VCM 30 is 12N, and the rated thrust of the servo motor 33 is 500N. When the rated thrust is set as the threshold value, the upper control unit 26e sets the low-load operation when pressurizing with a load of 0N or more and 12N or less to mount the component P, and with a load greater than 12N and 500N or less. The high-load operation is set when the component P is applied under pressure. In the above description, the low load operation and the high load operation are selected according to the magnitude of the target load. However, the selection may be made according to the type of the component P to be mounted.

  In FIG. 6, when the low load operation is selected, the control device 26 operates the XY robot unit 25 to move the component P held by the nozzle 28 of the component mounting head unit 1a upward in the XY direction mounting position. . Then, the control device 26 drives the servo motor 33 by the position control and drives the small VCM 30 by the torque control to mount the component P on the mounting object S.

  First, the control device 26 places the small VCM 30 in a pressurized state while maintaining a predetermined torque at a stroke lower limit (a state in which the small VCM 30 is most extended to the attachment object S side) by torque control. Then, the control device 26 controls the position of the servo motor 33 to lower the head unit 37 at a high speed in the direction of the mounting position, and further lowers the component P to a position where it is lowered by a predetermined pushing amount with respect to the mounted object S. Let As the head unit 37 descends, the component P descends and comes into contact with the workpiece S, and is further pushed in by a predetermined pushing amount. The impact generated at the time of contact between the component P and the mounted object S is reduced because the mass of the sub head unit 31 is lighter than that of the conventional structure. After the impact is generated, the control device 26 holds a predetermined torque by controlling the torque of the small VCM 30. When the servo motor 33 completes the lowering to the push-in position, the control device 26 stops the servo motor 33 at that position and causes the small VCM 30 to output a torque equivalent to the target load by torque control. Then, the control device 26 performs pressing with the target load until a predetermined time elapses, and then raises the servo motor 33 to a predetermined position at a high speed by position control, and the small VCM 30 is controlled by torque. To output a predetermined torque. As the head unit 37 rises, the small VCM 30 pressurizes at the stroke lower limit.

  On the other hand, when the high load operation is selected in FIG. 7, the control device 26 operates the XY robot unit 25 to move the component P held by the nozzle 28 of the component mounting head unit 1a above the mounting position in the XY direction. Move. Then, the control device 26 drives the servo motor 33 by switching the position control and the torque control as needed, and drives the small VCM 30 by the torque control to mount the component P on the attachment S.

  First, during the mounting operation, the control device 26 always puts the small VCM 30 in a pressurized state by the torque control at the stroke upper limit (a state in which the small VCM 30 is contracted most away from the mounted object S). Then, the control device 26 controls the position of the servo motor 33 to lower the head unit 37 in the mounting position direction at a high speed, and switches to a low speed at a predetermined position before the part P and the mounted object S contact each other. Further, the control device 26 lowers the component P at a low speed to bring it into contact with the workpiece S, and further pushes the torque command value in the servo motor 33. Contact is detected when the torque command value exceeds a predetermined value. And the control apparatus 26 switches control with respect to the servomotor 33 from position control to torque control, outputs the torque equivalent to a target load from the servomotor 33, and presses with a target load until predetermined time passes. When a predetermined time elapses, the control device 26 raises the head unit 37 to a predetermined position at a high speed by the position control of the servo motor 33.

  As described above, the component mounting apparatus according to the first embodiment selects one of a low load and a high load, and performs component mounting while switching the operation according to the selection. When mounting components with a low load operation, the impact on the component P and the object to be mounted S is reduced by reducing the weight of the component mounting head 1 (sub head unit 31). The head unit 1 can be operated, and the time required for mounting can be shortened. In addition, even in the case of high-load operation, even if the speed before the contact between the component P and the attachment S is made faster than the conventional operation due to the above weight reduction, it can be suppressed to the same level of impact as the conventional operation. Can be shortened.

  In the low load operation, the component P and the attachment S are brought into contact with each other at a high speed, but they may be brought into contact after switching from a high speed to a low speed at a predetermined position. Thereby, the impact load applied to the component P and the mounted object S can be further reduced.

  In the above description, the suction nozzle 28 using the suction action is used as the holding means for the component P. However, the present invention is not limited to this, and other component holding means such as a gripper may be used. Absent. Further, the servo motor 33 and the small VCM 30 are used as the motor for moving the nozzle holding the component P up and down. However, the present invention is not limited to this, and a combination of other motors such as both using the VCM may be used. The small VCM 30 provided in the head unit 37 may be another motor as long as it is a linear motion linear motor.

(Second Embodiment)
Hereinafter, a component mounting apparatus and a component mounting method according to a second embodiment of the present invention will be described with reference to the drawings. The overall configuration of the component mounting apparatus is the same as that of the first embodiment described above. About the following description, the same referential mark is attached | subjected with respect to the same structure, and detailed description is abbreviate | omitted.

  Next, the structure of the component mounting head unit 1 according to the second embodiment will be described with reference to FIG. FIG. 8 is a schematic diagram showing the configuration of the component mounting head portion 1b.

  In FIG. 8, the component mounting head unit 1b according to the second embodiment further includes a force sensor 45 with respect to the component mounting head unit 1a described in the first embodiment. Since the other components in the component mounting head unit 1b are the same as those in the component mounting head unit 1a of the first embodiment, the same components are denoted by the same reference numerals and detailed description thereof is omitted. To do.

  The force sensor 45 is installed between the pressure shaft 29 and the block 38, for example. The force sensor 45 detects the load applied to the component P to be mounted by detecting the load applied to the pressure shaft 29. Then, the force sensor 45 outputs a signal indicating the load to the control device 26. The position where the force sensor 45 is installed may not be between the pressure shaft 29 and the block 38. In order to detect the load applied to the component P more accurately, it is preferable to install the force sensor 45 as close to the nozzle 28 as possible.

  Next, the relationship between the control device 26 and the force sensor 45 will be described with reference to FIGS. FIG. 9 is a block diagram illustrating a configuration of the control device 26 according to the second embodiment. FIG. 10 is a block diagram illustrating the configuration of the small VCM control unit 261 and the host control unit 26e of FIG. FIG. 11 is a block diagram illustrating the configuration of the servo motor control unit 262 and the host control unit 26e of FIG. The internal configuration of the control device 26 according to the second embodiment is the same as that of the first embodiment, and therefore, the relationship between the force sensor 45 and the control device 26 will be mainly described here.

  As shown in FIGS. 9 to 11, the signal indicating the load output from the force sensor 45 is input to the small VCM control unit 261 and the servo motor control unit 262, respectively. The weight control unit 261b of the small VCM control unit 261 and the weight control unit 262b of the servo motor control unit 262 can perform weight feedback control based on the signals indicating the loads input from the force sensor 45, respectively. Here, the weighted feedback control refers to controlling the input current to the motor while performing feedback control so that the load follows the target load based on the signal indicating the load input from the force sensor 45. I mean. Further, the contact detection unit 262d of the servo motor control unit 262 detects the contact between the component P and the mounted object S according to the signal indicating the load.

  For example, as shown in FIG. 10, at the time of torque control, the weight control unit 261b torque-controls the input current of the power amplifier 261c based on the weight command from the weight command unit 261a. On the other hand, during weighted feedback control, based on the weighting command from the weighting command unit 261a and the signal indicating the load input from the force sensor 45, the weighting control unit 261b receives the input current to the power amplifier 261c so as to achieve the target load. To control.

  As shown in FIG. 11, during torque control, the weight control unit 262b torque-controls the input current of the power amplifier 262g via the switching unit 262f based on the weight command from the position / weight command unit 262a. On the other hand, during weighted feedback control, based on the weight command from the position / weight command unit 262a and the signal indicating the load input from the force sensor 45, the weight control unit 262b passes through the switching unit 262f so as to achieve the target load. Thus, the input current to the power amplifier 262g is controlled. In the torque control or the weighted feedback control, the contact detection unit 262d receives the load from the weight control unit 262b based on the signal indicating the load input from the force sensor 45 and the control switching signal from the position / weight command unit 262a. The switching unit 262f is switched so that the above command is output to the power amplifier 262g.

  Next, a specific example in which the control device 26 controls the operation of the component mounting head unit 1b will be described with reference to FIGS. FIG. 12 is a diagram illustrating a specific example in which the control device 26 controls the operation of the component mounting head unit 1b when mounting the component P with a low load. FIG. 13 is a diagram illustrating a specific example in which the control device 26 controls the operation of the component mounting head unit 1b when mounting the component P with a high load. Here, in FIG. 12 and FIG. 13, the first motor indicates the servo motor 33 and the second motor indicates the small VCM 30.

  The host control unit 26e of the control device 26 selects whether to operate the small VCM 30 and the servo motor 33 with a low load or a high load according to a target load for pressing the component P to be mounted against the mounted object S. The instruction is output to the small VCM control unit 261 and the servo motor control unit 262, respectively. Note that the threshold value used for selection is the same as in the first embodiment, and a detailed description thereof will be omitted.

  In FIG. 12, when the low load operation is selected, the control device 26 operates the XY robot unit 25 to move the component P held by the nozzle 28 of the component mounting head unit 1b above the mounting position in the XY direction. . Then, the control device 26 drives the servo motor 33 by the position control, and drives the small VCM 30 by the torque control and the weighted Fordback control to mount the component P on the mounting object S.

  First, the control device 26 puts the small VCM 30 into a pressurized state while maintaining a predetermined torque at the stroke lower limit by torque control. Then, the control device 26 controls the position of the servo motor 33 to lower the head unit 37 at a high speed in the direction of the mounting position, and further lowers the component P to a position where it is lowered by a predetermined pushing amount with respect to the mounted object S. Let As the head unit 37 descends, the component P descends and comes into contact with the workpiece S, and is further pushed in by a predetermined pushing amount. The impact generated at the time of contact between the component P and the mounted object S is reduced because the mass of the sub head unit 31 is lighter than that of the conventional structure. After the impact is generated, the control device 26 holds a predetermined torque by controlling the torque of the small VCM 30. When the servo motor 33 completes the lowering to the pushing position, the control device 26 stops the servo motor 33 at that position, switches the small VCM 30 to the weighted feedback control by the force sensor 45, and outputs the target load. Then, the control device 26 performs pressing with the target load until a predetermined time elapses, and then raises the servo motor 33 to a predetermined position at a high speed by position control, and the small VCM 30 is controlled by torque. To output a predetermined torque. As the head unit 37 rises, the small VCM 30 pressurizes at the stroke lower limit.

  On the other hand, in FIG. 13, when the high load operation is selected, the control device 26 operates the XY robot unit 25 to move the component P held by the nozzle 28 of the component mounting head unit 1b above the mounting position in the XY direction. Move. Then, the control device 26 drives the servo motor 33 by switching the position control and the weighted feedback control as appropriate, and drives the small VCM 30 by the torque control to mount the component P on the mounted object S.

  First, the control device 26 always puts the small VCM 30 in a pressurized state at the stroke upper limit by torque control during the mounting operation. Then, the control device 26 controls the position of the servo motor 33 to lower the head unit 37 in the mounting position direction at a high speed, and switches to a low speed at a predetermined position before the part P and the mounted object S contact each other. Furthermore, the control device 26 lowers the component P at a low speed to bring it into contact with the article to be mounted S, and further pushes the load detected by the force sensor 45. Contact is detected when the load detected by the force sensor 45 exceeds a predetermined value. Then, the control device 26 switches the control for the servo motor 33 from position control to weighted feedback control, causes the load detected by the force sensor 45 to follow the target load of the servo motor 33, and keeps the target load until a predetermined time elapses. Press. When a predetermined time elapses, the control device 26 raises the head unit 37 to a predetermined position at a high speed by the position control of the servo motor 33.

  As described above, the component mounting apparatus according to the second embodiment also selects one of the low load and the high load, and performs component mounting while switching the operation according to the selection. When mounting components with a low load operation, the impact on the component P and the object to be mounted S is reduced by reducing the weight of the component mounting head 1 (sub head unit 31). The head unit 1 can be operated, and the time required for mounting can be shortened. In addition, even in the case of high-load operation, even if the speed before the contact between the component P and the attachment S is made faster than the conventional operation due to the above weight reduction, it can be suppressed to the same level of impact as the conventional operation. Can be shortened. Furthermore, since the load applied to the component P to be mounted is directly detected by the force sensor 45, it is possible to accurately switch the operation during mounting, push in with a target load, and the like.

  In the low load operation, the component P and the attachment S are brought into contact with each other at a high speed, but they may be brought into contact after switching from a high speed to a low speed at a predetermined position. Thereby, the impact load applied to the component P and the mounted object S can be further reduced.

  In the above description, the suction nozzle 28 using the suction action is used as the holding means for the component P. However, the present invention is not limited to this, and other component holding means such as a gripper may be used. Absent. Further, the servo motor 33 and the small VCM 30 are used as the motor for moving the nozzle holding the component P up and down. However, the present invention is not limited to this, and a combination of other motors such as both using the VCM may be used. The small VCM 30 provided in the head unit 37 may be another motor as long as it is a linear motion linear motor.

  The component mounting apparatus and the component mounting method according to the present invention can reduce the tact time by increasing the mounting speed while suppressing the impact at the time of contact between the component and the mounted object, and mount the component on the mounted object. It is useful as an apparatus and a method for performing the above, and can be applied to all parts mounting machines.

Schematic which shows the whole structure of the component mounting apparatus which concerns on the 1st and 2nd embodiment of this invention. Schematic which shows the structure of the component mounting head part 1a which concerns on the 1st Embodiment of this invention. The block diagram which shows the structure of the control apparatus 26 which concerns on the 1st Embodiment of this invention. The block diagram which shows the structure of the small VCM control part 261 and the high-order control part 26e of FIG. The block diagram which shows the structure of the servomotor control part 262 and the high-order control part 26e of FIG. The figure explaining the specific example in which the control apparatus 26 controls operation | movement of the components mounting head part 1a when mounting components P with a low load. The figure explaining the specific example in which the control apparatus 26 controls operation | movement of the components mounting head part 1a, when mounting components P with a heavy load. Schematic which shows the structure of the component mounting head part 1b which concerns on the 2nd Embodiment of this invention. The block diagram which shows the structure of the control apparatus 26 which concerns on the 2nd Embodiment of this invention. The block diagram which shows the structure of the small VCM control part 261 and the high-order control part 26e of FIG. The block diagram which shows the structure of the servo motor control part 262 of FIG. 9, and the high-order control part 26e. The figure explaining the specific example in which the control apparatus 26 controls operation | movement of the components mounting head part 1b, when mounting components P with a low load. The figure explaining the specific example in which the control apparatus 26 controls operation | movement of the components mounting head part 1b, when mounting components P with a heavy load. Schematic showing a component mounting head controlled by a conventional component mounting control device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Component mounting head part 28 ... Nozzle 29 ... Pressure shaft 30 ... Small VCM
31 ... Sub head unit 32 ... Ball screw 33 ... Servo motor 34 ... Encoder 35 ... Rotating shaft servo motor 36 ... Rotating shaft encoder 37 ... Head unit 38 ... Blocks 39, 42, 43 ... Bearing 40 ... Nuts 41 ... Rotation Shaft shaft 22 ... Moving table unit 23 ... Component supply unit 25 ... XY robot unit 26 ... Control device 26a ... Component mounting head control unit 261 ... Small VCM control unit 261a ... Weight command unit 261b, 262b ... Weight control unit 261c, 262g ... Power amplifier 262 ... Servo motor control unit 262a ... Position / weight command unit 262c ... Position control unit 262d ... Contact detection unit 262e ... Speed control unit 262f ... Switching unit 263 ... Rotary axis servo motor control unit 26b ... Moving table control unit 26c ... Part supply control unit 26d ... XY robot control unit 26e Upper control unit 26E1 ... With low load operation command unit 26E2 ... operation command section for high load 27 ... component feed tray 45 ... force sensor

Claims (7)

A component mounting apparatus for mounting a component on an object to be mounted,
A holding part for holding the component;
A support member;
A first motor for raising and lowering the support member;
A sub head unit provided with the holding portion at its tip;
A second motor provided on the support member for raising and lowering the sub head unit;
A controller that drives at least one of the first motor and the second motor to control a position in a height direction of the component held by the holding unit and a load that presses the component against the mounted object; Component mounting device.   The component mounting apparatus according to claim 1, further comprising a load detection unit that is provided in the sub head unit and detects a load that presses the component held by the holding unit against the mounted object. A component mounting method for mounting a component on a workpiece,
Holding the part with a holding part;
A step of raising and lowering a support member that supports a second motor that raises and lowers the sub head unit provided with the holding portion at the tip by driving the first motor;
A step of selecting at least one of the first motor and the second motor as a motor for driving at least one of the first motor and the second motor according to a target load when pressing the component held by the holding unit against the attachment;
Driving at least one of the selected first motor and second motor to control a position in the height direction of the component held in the holding portion and a load for pressing the component against the mounted object; Including parts mounting method. The maximum thrust of the second motor is smaller than the maximum thrust of the first motor,
In the selecting step, when the target load is equal to or less than the maximum thrust of the second motor, the second motor is selected as a motor to be driven when the component held by the holding portion is pressed against the attachment object. The component mounting method according to claim 3, wherein: When the target load is below a predetermined threshold value,
The step of raising and lowering the support member includes driving the first motor by position control in a state where the second motor is driven in the direction in which the sub head unit extends most, thereby moving the support member at a relatively high speed. Lower until the part comes into contact with the workpiece,
The step of controlling the load to be pressed stops the driving of the first motor, drives the second motor, and holds the position in the height direction of the part held in the holding part and the part on the mounted object. The component mounting method according to claim 4, wherein a load to be pressed is controlled. When the target load is greater than a predetermined threshold value,
The step of raising and lowering the support member includes driving the first motor by position control in a state where the second motor is driven in the direction in which the sub head unit is contracted most, and moving the support member at a relatively high speed. Lowering to a predetermined position, lowering the support member from the predetermined position at a speed slower than the high speed until the component comes into contact with the mounted object,
The step of controlling the pressing load controls the position in the height direction of the component held by the holding unit by driving the first motor and the load for pressing the component against the mounted object. The component mounting method according to claim 4. The component mounting method further includes a step of detecting a load applied to the sub head unit,
The step of raising and lowering the support member detects contact between the component and the mounted object based on the detected load,
The step of controlling the load to be pressed controls feedback of the detected load to the target load to control the load that presses the component against the mounted object. Or the component mounting method of 6.

Images