WO2020039512A1

WO2020039512A1 - Moving body driving control system

Info

Publication number: WO2020039512A1
Application number: PCT/JP2018/030933
Authority: WO
Inventors: 隆志城戸
Original assignee: 株式会社Ｆｕｊｉ
Priority date: 2018-08-22
Filing date: 2018-08-22
Publication date: 2020-02-27
Also published as: JPWO2020039512A1; JP6937921B2

Abstract

The present invention is provided with a function for operating a dynamic brake and braking, when a servo control is unexecutable while the servo control is performed which moves a moving body (14) to a target position by taking a servo motor (25) or a linear servo motor (27) as a driving source. A control unit (41), which controls the servo motor or the linear servo motor, takes a section within a prescribed distance from a movement limit position of the moving body as a speed limit section in which moving speed is limited to a prescribed speed limit or lower, and corrects deceleration according to the distance between a target position and the movement limit position, when the target position is set within the speed limit section so that the moving body is moved toward the movement limit position within the speed limit section.

Description

Mobile drive control system

The present specification has a function of operating a dynamic brake to perform braking when servo control becomes impossible during servo control for moving a moving body to a target position using a servo motor or a linear servo motor as a drive source. This discloses a technique relating to a moving body drive control system. In the following description, the term “servo motor” simply means either a rotary servo motor or a linear servo motor (linear servo motor).

Generally, a moving body drive control system using a servo motor as a driving source drives a servo motor to move a moving body to a target position, as described in Japanese Patent Application Laid-Open No. 2016-213993. If servo control becomes impossible due to a sensor error or power failure during servo control, the dynamic brake is activated to short-circuit the motor winding terminals, thereby braking the servo motor and moving Stop moving.

JP 2016-213993 A

Generally, the braking force of the servomotor by the dynamic brake is smaller than the braking force of the servo control, so that the braking distance by the dynamic brake is longer than the braking distance by the servo control. For this reason, when the target position is set near the movement limit position (mechanical end) of the moving body and the servo control is executed, when the servo control becomes impossible near the target position, the dynamic brake is activated. However, there is a possibility that the moving body does not sufficiently decelerate until the moving body reaches the movement limit position and collides vigorously with a stopper or the like at the movement limit position, and the impact may damage the mechanism of the driving device. is there.

In order to solve the above-mentioned problem, a function of operating a dynamic brake to perform braking when servo control becomes impossible during servo control for moving a moving body to a target position using a servo motor or a linear servo motor as a driving source. A target position setting unit that sets the target position; and a reduction in acceleration, a moving speed, and a deceleration section of an acceleration section of the moving body until the moving body is moved to the target position. And a control unit for controlling a speed, wherein the control unit sets a section within a predetermined distance to a movement limit position of the moving body as a speed limit section that limits the movement speed to a predetermined speed limit or less, The target position setting unit sets the target position in the speed limit section so as to move the moving body in the direction of the movement limit position in the speed limit section. Wherein said target position if in accordance with a distance Lbl between the movement limit position is obtained so as to correct the deceleration.

In this case, if the speed limit in the speed limit section is excessively reduced to prevent the moving body from colliding with a stopper or the like at the movement limit position when the dynamic brake is activated, the moving speed of the moving body in the speed limit section decreases. It becomes too much and the productivity decreases.

In that regard, in the above configuration, when the target position is set in the speed limit section so as to move the moving body in the direction of the movement limit position in the speed limit section, the distance Lbl between the target position and the movement limit position The deceleration is corrected in accordance with the following formula, so that control can be performed such that the deceleration is increased as the target position is closer to the movement limit position, and the moving speed of the moving object in the speed limit section is reduced. For this reason, even if the servo control becomes impossible near the target position set in the speed limit section and the dynamic brake is actuated, in a short section until the moving body reaches the stopper at the movement limit position, The moving speed of the moving body can be sufficiently reduced by the dynamic brake, and the speed (impact force) at which the moving body collides with the stopper at the movement limit position can be sufficiently reduced. In addition, since the deceleration is corrected according to the distance Lbl between the target position and the movement limit position, an appropriate deceleration can be set according to the distance Lbl between the target position and the movement limit position. In addition, it is possible to minimize the decrease in the moving speed of the moving object in the speed limited section, and to minimize the decrease in productivity due to the decrease in the moving speed.

FIG. 1 is a perspective view showing a configuration of a main part of a component mounter in one embodiment. FIG. 2 is a block diagram showing a configuration of a control system of the component mounter. FIG. 3 is a diagram illustrating the relationship between the speed limit and the speed command in the speed limit section. FIG. 4 is a flowchart showing the flow of the processing of the deceleration correction program in the speed limit section.

Hereinafter, an embodiment in which the moving object drive control system disclosed in this specification is mounted on the component mounter 11 will be described.

First, the configuration of the component mounter 11 will be described with reference to FIG.
In the component mounter 11, a component supply device 12 that supplies components is set detachably. The component supply device 12 to be set in the component mounter 11 may be any of a tray feeder, a tape feeder, a bulk feeder, a stick feeder, and the like, and of course, a plurality of types of feeders may be mixed. The component mounter 11 includes a conveyor 13 for transporting a circuit board (not shown), a mounting head 14 (moving body) for mounting components supplied by the component supply device 12 on the circuit board, and a mounting head 14. A mounting head moving device 15 for moving in the X-axis direction (transfer direction of the circuit board) and a Y-axis direction perpendicular to the X-axis direction, and a nozzle station 16 for mounting a suction nozzle (not shown) for replacement are provided. ing.

(4) A suction nozzle (not shown) for sucking a component supplied by the component supply device 12 is exchangeably held by the mounting head 14. The component mounter 11 is provided with a component imaging camera 17 for imaging the component held by the suction nozzle from below, and the mounting head 14 is provided with a mark imaging camera 18 for imaging a reference position mark or the like of the circuit board. Is provided.

The mounting head 14 is provided with a Z-axis slide 24 driven in the Z-axis direction (up-down direction) by a Z-axis motor 22. The suction nozzle is moved by lowering / elevating the Z-axis slide 24 during a component suction operation or a component mounting operation. Is lowered / elevated.

The mounting head moving device 15 includes an X-axis slide device 26 using an X-axis servo motor 25 as a drive source, and a Y-axis slide device 28 using a Y-axis linear servo motor 27 as a drive source. The X-axis slide device 26 rotates the X-axis ball screw 29 by the X-axis servo motor 25 to move the X-axis slide (not shown) to which the mounting head 14 is attached along the X-axis guide 30 in the X-axis direction. Move. The X-axis guide 30 is supported by a Y-axis guide 31 of a Y-axis slide device 28 so as to be slidable in the Y-axis direction, and has a X-axis slide 32 attached to a mover 33 of the Y-axis linear servomotor 27. The shaft guide 30 is connected. Thus, the X-axis slide device 26 is moved in the Y-axis direction along the Y-axis guide 31 by the Y-axis linear servomotor 27. The stator 34 of the Y-axis linear servomotor 27 is provided with two rows of magnets facing each other across the mover 33 so as to extend parallel to the Y-axis direction.

The control device 41 of the component mounter 11 is mainly configured by a computer, and includes an input device 42 such as a keyboard, a mouse, and a touch panel, a display device 43 such as an LCD, an EL, and a CRT, and an operation of each function of the component mounter 11. Is connected to a storage device 44 such as a hard disk device for storing various control programs for controlling the deceleration and a deceleration correction program in the speed limit section shown in FIG.

During operation (during production), the control device 41 of the component mounter 11 controls operations of the X-axis servo motor 25, the Y-axis linear servo motor 27, the Z-axis motor 22 and the like of the mounting head moving device 15 to perform mounting. The head 14 is moved between the component suction position on the component supply device 12 side and the component mounting position on the circuit board to execute the component suction operation and the component mounting operation. The X-axis servo motor 25 and the Y-axis linear servo motor 27, which are the driving sources of the mounting head moving device 15, have a servo control due to some cause such as a sensor abnormality or power failure during the servo control for moving the mounting head 14 to the target position. A dynamic brake function is provided for short-circuiting the terminals of the motor winding and braking the motor when the motor cannot be executed.

The control device 41 of the component mounter 11 functions as a target position setting unit that sets a target position at which the mounting head 14 is moved, and accelerates, moves, and decelerates in an acceleration section until the mounting head 14 is moved to the target position. It also functions as a control unit that controls the deceleration of the section. As shown in FIG. 3, the control device 41 of the component mounter 11 limits the moving speed of a section within a predetermined limit distance from the movement limit position (mechanical end) of the mounting head 14 to a predetermined speed limit or less. When a target position is set in the speed limit section so as to move the mounting head 14 in the direction of the movement limit position in the speed limit section, the speed is determined according to the distance Lbl between the target position and the movement limit position. Thus, the deceleration Bi て is corrected by the following equation (1).

{Bi} = 2 · Z (Z · Lbl + Vend) (1)

{Where, Z is the slope of a straight line indicating the change characteristic of the speed limit in the speed limit section, Lbl is the distance between the target position and the movement limit position, and Vend} is the allowable speed which is the speed limit at the movement limit position.

Even when the target position is set within the speed limit section, if the mounting head 14 moves to the target position in a direction opposite to the movement limit position, the mounting head 14 collides with a stopper or the like at the movement limit position. Since there is no danger of deceleration, the deceleration is not corrected by the above equation (1).

の長 The length of the speed limit section (limit distance) is set based on the braking characteristics of the dynamic brake. In the present embodiment, the speed limit in the speed limit section linearly decreases from the speed limit section start position toward the movement limit position such that the movement speed at the movement limit position becomes a predetermined allowable speed Vend #. It is set as follows. The allowable speed Vend # at the movement limit position is set to the movement speed of the mounting head 14 such that even if the mounting head 14 collides with a stopper or the like at the movement limit position, the impact does not damage the mechanism of the mounting head moving device 15. I have. This allowable speed Vend # may be a constant value set by the manufacturer or may be changed by the user.

Further, as shown in FIG. 3, when the movement of the mounting head 14 is started in the direction of the movement limit position within the speed limit section, the control device 41 of the component mounter 11 performs mounting by acceleration after the start of movement. Before the moving speed of the head 14 reaches the speed limit, the speed is switched from acceleration to deceleration, and the command speed profile is corrected so that the trajectory of the moving speed is in contact with a straight line indicating the change characteristic of the speed limit within the deceleration section.

By the way, in the conventional system in which the speed limit section is not provided, as shown by the dotted line in FIG. 3, even when the movement of the mounting head 14 is started toward the movement limit position in the section corresponding to the speed limit section, The moving speed is not limited to the speed limit or less, and the speed is accelerated to the maximum speed within a range where the deceleration to the target position by the servo control is possible. For this reason, if the servo control becomes infeasible near the maximum speed, the mounting head 14 is not sufficiently decelerated until the mounting head 14 reaches the movement limit position even if the dynamic brake is actuated. 14 may collide vigorously, and the impact may damage the mounting head moving device 15.

In this regard, in the present embodiment, as shown in FIG. 3, when the movement of the mounting head 14 is started in the direction of the movement limit position within the speed limit section, the movement of the mounting head 14 is accelerated after the movement is started. Before the speed reaches the speed limit, the speed is switched from acceleration to deceleration, and the command speed profile is corrected so that the trajectory of the moving speed is in contact with a straight line indicating the change characteristic of the speed limit within the deceleration section. As a result, no matter where the dynamic brake is activated in the speed limit section, the moving speed of the mounting head 14 is limited to the speed limit or less, and the mounting head 14 is moved for a short time until it reaches the stopper at the movement limit position. Thus, the moving speed can be sufficiently reduced by the dynamic brake, and the speed (impact force) at which the mounting head 14 collides with the stopper or the like at the movement limit position can be sufficiently reduced.

The control device 41 of the component mounter 11 repeatedly executes the deceleration correction program in the speed limit section in FIG. 4 at a predetermined cycle while the component mounter 11 is operating, thereby moving the mounting head 14 within the speed limit section. Each time a target position is set within the speed limit section so as to move in the direction of the position, the deceleration is corrected to correct the commanded speed profile. Hereinafter, the processing content of the deceleration correction program in the speed limit section in FIG. 4 will be described.

When the control device 41 of the component mounter 11 starts the deceleration correction program in the speed limit section in FIG. 4, first, in step 101, the mounting head 14 is moved in the direction of the movement limit position in the speed limit section. It is determined whether or not the target position has been set within the speed limit section. For example, if the target position is not within the speed limit section, or if the moving direction of the mounting head 14 is in the opposite direction to the movement limit position even when the target position is within the speed limit section, “ No, the program is terminated. That is, when the target position is not within the speed limit section, or when the moving direction of the mounting head 14 is opposite to the movement limit position even when the target position is within the speed limit section, the mounting head 14 Since there is no possibility of collision with a position stopper or the like, the deceleration is not corrected.

On the other hand, if it is determined “Yes” in step 101, if the servo control cannot be executed for some reason during the servo control, the mounting head 14 may be moved to the stopper at the movement limit position even if the dynamic brake is activated. Since there is a possibility of collision, the routine proceeds to step 102, where the deceleration is corrected by the above equation (1). After that, the process proceeds to step 103, in which the moving speed of the mounting head 14 is switched from acceleration to deceleration before the moving speed of the mounting head 14 reaches the speed limit due to the acceleration after the start of the movement, and the trajectory of the moving speed changes the speed characteristic of the speed limit within the deceleration section. The command speed profile is corrected so as to be in contact with the indicated straight line, and the program ends.

By the way, in order to prevent the mounting head 14 from colliding with a stopper or the like at the movement limit position during the dynamic braking operation, if the speed limit in the speed limit section is excessively lowered, the movement speed of the mounting head 14 in the speed limit section becomes lower. Too slow and productivity drops.

In this regard, in this embodiment, when the target position is set in the speed limit section so as to move the mounting head 14 in the direction of the movement limit position in the speed limit section, the position between the target position and the movement limit position is set. Since the deceleration is corrected in accordance with the distance Lbl, it is possible to perform control such that as the target position is closer to the movement limit position, the deceleration is increased and the movement speed of the mounting head 14 in the speed limit section is reduced. Become. For this reason, even if the servo control becomes impossible near the target position set in the speed limit section and the dynamic brake is actuated, the mounting head 14 is moved in a short section until the mounting head 14 reaches the stopper at the movement limit position. The moving speed of the mounting head 14 can be sufficiently reduced by the dynamic brake, and the speed (impact force) at which the mounting head 14 collides with a stopper or the like at the movement limit position can be sufficiently reduced. The mounting head moving device 15 can be prevented from being damaged due to collision with the stopper or the like. In addition, since the deceleration is corrected according to the distance Lbl between the target position and the movement limit position, an appropriate deceleration can be set according to the distance Lbl between the target position and the movement limit position. In addition, it is possible to minimize the decrease in the moving speed of the mounting head 14 in the speed limited section, and to minimize the decrease in productivity due to the decrease in the moving speed.

In the present embodiment, the change characteristic of the speed limit in the speed limit section is set by a straight line, but may be set by a curve such as a quadratic curve.

Further, in the present embodiment, the deceleration is corrected under predetermined conditions for the X-axis servo motor 25 and the Y-axis linear servo motor 27. However, when the Z-axis motor 22 is configured by a servo motor or a linear servo motor. Alternatively, the deceleration of the Z-axis motor 22 may be corrected under the same conditions.

In addition, the scope of application of the present invention is not limited to the component mounter 11, but may be applied to devices (such as solder printing machines) in each process arranged on a component mounting line for producing a component mounted board. The present invention may be applied to devices in each process of a production line other than a component mounting line. In short, as long as the device is equipped with a moving body driving device that drives a moving body by a servomotor, the present invention can be applied to any device. It can be implemented by applying the invention.

In addition, the present invention is not limited to the present embodiment. For example, the configuration of the moving body driving device (mounting head moving device 15) may be appropriately changed, and various changes may be made without departing from the gist. It goes without saying that you can do it.

11: Component mounting machine, 12: Component supply device, 14: Mounting head (moving body), 15: Mounting head moving device, 25: X-axis servo motor, 26: X-axis slide device, 27: Y-axis linear servo motor, 28: Y-axis slide device, 41: Control device (target position setting unit, control unit)

Claims

A moving body drive control system having a function of operating a dynamic brake to perform braking when servo control becomes impossible during servo control for moving a moving body to a target position using a servo motor or a linear servo motor as a drive source At
A target position setting unit for setting the target position,
A control unit that controls acceleration of an acceleration section of the moving body until moving the moving body to the target position, moving speed, and deceleration of a deceleration section,
The control unit may set a section within a predetermined distance from the movement limit position of the moving object as a speed limit section that limits the moving speed to a predetermined speed limit or less, and the target position setting unit may set the target position setting unit within the speed limit section. When the target position is set in the speed limit section so as to move the moving body in the direction of the movement limit position, the deceleration is performed according to a distance Lbl between the target position and the movement limit position. Moving control system.
2. The control unit sets the speed limit in the speed limit section to decrease toward the movement limit position such that the movement speed at the movement limit position becomes a predetermined allowable speed Vend. 3. 4. A moving body drive control system according to claim 1.
The moving body according to claim 2, wherein the control unit sets the speed limit in the speed limit section to linearly decrease toward the movement limit position, and calculates the deceleration by the following equation. Drive control system.
The deceleration = 2 · Z (Z · Lbl + Vend)
Here, Z is the slope of the change characteristic line of the speed limit Lbl is the distance between the target position and the movement limit position Vend is the allowable speed at the movement limit position
When the movement of the moving body is started in the direction of the movement limit position within the speed limit section, the control unit accelerates the movement speed before the movement speed reaches the speed limit by acceleration after the start of movement. 4. The moving body drive control system according to claim 2, wherein the command speed profile is corrected such that the speed is switched from deceleration to deceleration and the trajectory of the moving speed is in contact with the change characteristic line of the speed limit within the deceleration section.
The moving body drive control system according to any one of claims 1 to 4, wherein the predetermined distance that is the length of the speed limit section is set based on a braking characteristic of the dynamic brake.
The moving body drive control system according to claim 1, wherein the moving body is a mounting head of a component mounting machine.