KR20130011953A - Electronic component mounting apparatus - Google Patents

Abstract

PURPOSE: An electronic component mounting apparatus is provided to search for an origin point of a belt by an origin point detection signal and to stably perform return to an origin point of a belt. CONSTITUTION: A suction nozzle is installed on a nozzle shaft by a theta shaft motor. A driving pulley(22) is installed on a shaft of the theta shaft motor. A first driving pulley(12c) is installed in the nozzle shaft. A belt(23) has the number of saw tooth. An origin return unit returns the belt based on a first origin point detection signal and a second origin point detection signal. [Reference numerals] (AA,CC) Number of teeth m; (BB) Number of teeth L; (DD) Number of teeth P

Description

ELECTRONIC COMPONENT MOUNTING APPARATUS

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting apparatus for mounting a component supplied from an electronic component supply apparatus onto a substrate, and in particular, the origin of a belt connecting the shaft of a nozzle that sucks the component with the shaft of a motor that rotates the nozzle. Iii) an electronic component mounting apparatus for performing a return.

An adsorption nozzle capable of each of the movement in the X- and Y-axis directions on the plane, the Z-axis direction in the vertical direction, and the rotation around the θ-axis in the rotational direction about the Z-axis adsorbs and holds the electronic component. BACKGROUND ART Electronic component mounting devices capable of moving an electronic component onto a substrate and mounting on the substrate are known.

In such an electronic component mounting apparatus, there exists a technique of patent document 1 as a technique which improves the mounting precision by improving the rotation position precision about the (theta) axis of an adsorption nozzle. This electronic component mounting apparatus connects the shaft of an adsorption nozzle and the shaft of the (theta) -axis motor which rotates an adsorption nozzle with a belt, and transmits the driving force of a (theta) -axis motor to an adsorption nozzle, and displays a belt mark on the said belt, and this belt By detecting the mark by the sensor, the origin of the belt is searched to perform the origin return of the belt.

Japanese Patent Publication No. 2009-124083

However, in the conventional apparatus described in Patent Document 1, it is sometimes difficult to detect the belt mark due to aging deterioration, friction of the belt, or the like, and durability is unstable.

Accordingly, it is a problem to stably perform the origin return of the belt connecting the shaft of the suction nozzle and the shaft of the motor for rotating the suction nozzle.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, this invention provides the electronic component mounting apparatus which has each characteristic of the following (1)-(8).

(One)

An electronic component mounting apparatus for absorbing an electronic component by a suction nozzle mounted on a nozzle shaft rotated by a θ axis motor, and mounting the electronic component on a substrate, on the axis of the θ axis motor, coaxially with the axis. An attached toothed drive pulley, a toothed first driven pulley coaxially mounted to the nozzle shaft, a toothed second driven pulley, the drive pulley, the first driven pulley and the second A toothed belt spanning a driven pulley and having a tooth number equal to a minimum common multiple of the number of teeth of the drive pulley and the number of teeth of the second driven pulley, and when the driving pulley is at the origin, a first origin detection signal is generated. First origin detecting means for outputting, second origin detecting means for outputting a second origin detecting signal when the second driven pulley is at the origin, and the first outputting means for outputting by the first origin detecting means And an origin return means for returning the belt to the origin based on the origin detection signal and the second origin detection signal output by the second origin detection means.

In the electronic component mounting apparatus having such a feature, since the number of teeth of the belt for transmitting the driving force of the θ-axis motor to the nozzle shaft matches the minimum common multiple of the number of teeth of the driving pulley and the number of teeth of the second driven pulley, Only once during 1 week, the timing at which the driving pulley and the second driven pulley are both origin can be made. Moreover, regularity can be provided to the shift amount from the origin of the 2nd driven pulley when the drive pulley is at the origin, and the shift amount from the origin of the drive pulley when the second driven pulley is at the origin.

For this reason, based on the output timing of the first origin detection signal and the output timing of the second origin detection signal, it is possible to search the belt origin appropriately and perform the home return. At this time, since it is not necessary to display the belt mark on the belt as in the conventional apparatus, even if deterioration or friction of the belt occurs, the belt origin return operation is not affected. Therefore, the zero point return of the belt can be performed stably.

(2)

An electronic component mounting apparatus according to (1), comprising: a plurality of second driven pulleys, and a second origin point for outputting respective second origin detection signals when each of the second driven pulleys is at the origin; And the belt is returned to the origin based on the detection means and the second origin detection signal output by the second origin detection means.

As described above, in the electronic component mounting apparatus provided with a plurality of driven pulleys for the belt home search, a home sensor is provided in each driven pulley to determine whether all the home sensors are in an ON state. The belt can be returned to the home position as in the case where only one driven pulley is installed.

(3)

The electronic component mounting apparatus according to the above (1) or (2), wherein the drive pulley and the second driven pulley are both assembled so as to be at the origin when the belt is at the origin. Mounting device.

In the electronic component mounting apparatus having such a feature, the output timing of the first origin detection signal and the output timing of the second origin detection signal can be made to coincide only when the belt is at the origin. Therefore, the belt origin can be easily searched for.

(4)

In the electronic component mounting apparatus according to (1) or (2), the home position return means simultaneously detects the home position by the first home position detection means and the second home position detection means while rotating the θ-axis motor. And a search means for searching for a timing for outputting a signal, and a motor stop means for stopping rotation of the θ-axis motor at the timing searched by the search means.

In the electronic component mounting apparatus having such a feature, by rotating the θ-axis motor by using the coincidence of the output timing of the first origin detection signal and the output timing of the second origin detection signal only when the belt is at the origin, Rotation of the θ-axis motor when it is confirmed whether the second home detection signal is also output when the first home detection signal is output, and when the second home detection signal is also output when the first home detection signal is output. To stop. Thereby, the (theta) -axis motor can be stopped when the belt returns to the origin. That is, in such an electronic component mounting apparatus, the home search and the home return of the belt can be performed simultaneously.

(5)

The electronic component mounting apparatus according to (1) or (2), further comprising pulley angle detecting means for detecting a rotation angle of the second driven pulley, wherein the home return means comprises the first home detection means. Shift amount calculation means for calculating a shift amount from the origin of the belt at the point in time based on the rotation angle of the second driven pulley detected by the angle detection means when outputting the first origin detection signal; Motor control amount calculation means for calculating a rotational direction and rotation amount of the θ-axis motor required to return the belt to the origin, based on the deviation amount from the origin of the belt calculated by the deviation amount calculation means; When the θ-axis motor is rotated in the rotational direction calculated by the motor control amount calculation means, by the rotation amount calculated by the motor control amount calculation means. The key is an electronic component mounting apparatus comprising a motor drive means.

In the electronic component mounting apparatus having such a feature, since the rotation angle of the second driven pulley when the driving pulley is at the origin is regular, the rotation of the second driven pulley at the time when the first origin detection signal is outputted If the angle can be detected, the position (deviation amount from the origin) of the present belt can be appropriately recognized based on the detected angle. Then, after recognizing the current position of the belt, the θ-axis motor can be rotated at once to return the belt to the origin. In this way, the return operation of the belt origin can be performed appropriately and quickly.

(6)

The electronic component mounting apparatus according to (1) or (2) above, further comprising motor angle detection means for detecting a rotation angle of the θ-axis motor, wherein the origin return means comprises the second origin detection means. A shift amount calculation means for calculating a shift amount from the origin of the belt at that point of time based on the rotation angle of the θ-axis motor detected by the motor angle detection means when an origin detection signal is output; Motor control amount calculation means for calculating the rotational direction and amount of rotation of the θ axis motor required to return the belt to the origin based on the amount of deviation from the origin of the belt calculated by the deviation amount calculation means, and the θ axis The motor which rotates a motor by the rotation amount computed by the said motor control quantity calculation means in the rotation direction computed by the said motor control quantity calculation means. Electronic parts mounting apparatus comprising a driving means.

In the electronic component mounting apparatus having such a feature, since the rotation angle of the θ-axis motor (drive pulley) when the second driven pulley is at the origin is regular, θ at the time when the second origin detection signal is output If the rotation angle of the shaft motor (drive pulley) can be detected, the position (deviation amount from the origin) of the present belt can be appropriately recognized based on the detection angle. After recognizing the current position of the belt, the θ-axis motor can be rotated at once to return the belt to the origin. In this way, the return operation of the belt origin can be performed appropriately and quickly.

(7)

In the electronic component mounting apparatus according to (6), the shift amount calculation means detects that the first origin detection means outputs a first origin detection signal, and then rotates the θ-axis motor by a predetermined angle. Each time, the second home position detecting means checks whether or not the second home position detection signal outputs the second home position detection signal, and when the second home position detection means confirms that the second home position detection signal has been output, the motor angle detecting means detects the result. And the shift amount is calculated based on the rotation angle of the θ-axis motor.

In the electronic component mounting apparatus provided with such a feature, even when the second origin detecting means has a width in a range where the origin of the second driven pulley can be detected (response range of the sensor), the predetermined angle is appropriately set. The timing at which the second origin detection signal is output can be detected with good accuracy.

(8)

The electronic component mounting apparatus according to (7), wherein the predetermined angle is determined according to a ratio of the number of teeth of the drive pulley and the number of teeth of the second driven pulley.

In the electronic component mounting apparatus having such a feature, after the first origin detection signal is detected by using the regularity in the amount of shift from the origin of the second driven pulley when the driving pulley is at the origin, the second origin detection signal is detected. The θ-axis motor can be rotated so as to be a belt position where the home position detection signal may be output. That is, the presence or absence of the output of the second origin detection signal can be confirmed only at the belt position where the second origin detection signal is likely to be output, so that the output timing of the second origin detection signal can be searched efficiently and with high accuracy.

(9)

In the electronic component mounting apparatus according to (1), a motor encoder capable of detecting the home position of the drive pulley and an origin sensor capable of detecting the home position of the second driven pulley are further provided, and the home position of the drive pulley is provided. And the origin of the belt connecting the shaft of the suction nozzle and the shaft of the motor which rotates the suction nozzle by the relationship between the origin position of the second driven pulley, and the homing is performed. Electronic component mounting device.

According to the electronic component mounting apparatus as described in said (1)-(9), the origin detection signal of the drive pulley attached to the motor shaft and the origin detection of the 2nd driven pulley provided separately from the 1st driven pulley attached to the nozzle shaft Since the origin of the belt itself can be searched by the signal, the origin return of the belt can be performed without displaying the belt mark. Therefore, even if deterioration and friction of the belt occur, the belt return to the origin can be stably performed without affecting the return operation of the belt origin. As a result, stable mounting can be established.

1 is a plan view of an electronic component mounting apparatus according to a first embodiment of the present invention.
2 is a perspective view showing an outline of a mounting head and a θ-axis rotation mechanism of the mounting head.
3 is a plan view of the main part of the θ-axis rotation mechanism.
4 is a block diagram showing a configuration of a control system of the electronic component mounting apparatus.
Fig. 5 is a flowchart showing the belt origin search processing procedure of the electronic component mounting apparatus according to the first embodiment.
Fig. 6 is a diagram showing the relationship between the state of the belt and the Z phase, and is an image diagram in which one circumference of the belt is unfolded in one dimension.
It is a figure which shows the normal state of the belt and the state developed one-dimensionally.
FIG. 8 is a diagram for explaining the operation of the electronic component mounting apparatus according to the first embodiment, which shows the state of the belt at the point in time when the motor encoder outputs the Z phase.
9 is a diagram illustrating an example in which two second driven pulleys are provided.
Fig. 10 is a flowchart showing a belt origin search processing procedure of the electronic component mounting apparatus according to the second embodiment.
FIG. 11 is a view showing an angle of rotation of the pulley at the point of time of detecting an image of the motor encoder in the electronic component mounting apparatus according to the second embodiment.
12 is a flowchart showing a belt origin search processing procedure of the electronic component mounting apparatus according to the third embodiment.
FIG. 13 is a diagram showing the motor encoder output at the point of time when the home position sensor in the electronic component mounting apparatus according to the third embodiment detects the negative phase, and is an image diagram in which one circumference of the belt is unfolded in one dimension.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment)

(Configuration)

In FIG. 1, the electronic component mounting apparatus 1 is equipped with the pair of conveyance rails 11 which extend in the X direction and exist in the upper surface of the base 10. As shown in FIG. The conveyance rail 11 supports both side portions of the circuit board 5 and is driven by a conveying motor (not shown) to convey the circuit board 5 in the X direction.

In addition, the electronic component mounting apparatus 1 includes a mounting head 12. The mounting head 12 includes a plurality of adsorption nozzles for adsorbing electronic components in the lower portion thereof, and is horizontally moved on the base 10 in the XY direction by the X-axis gantry 13 and the Y-axis gantry 14. It is configured to be.

The electronic component mounting apparatus 1 is equipped with the electronic component supply apparatus 15 which supplies an electronic component with a tape feeder etc. in the both sides of the conveyance rail 11 in the Y direction. Then, the electronic component supplied from the electronic component supply device 15 is vacuum sucked by the suction nozzle of the mounting head 12, mounted on the circuit board 5, and mounted.

Moreover, between the component supply apparatus 15 and the circuit board 5, the recognition camera 7 which consists of a CCD camera is arrange | positioned. The recognition camera 7 detects the positional shift of the electronic component (deviation between the center position of the suction nozzle and the center position of the adsorbed component) and the electrons adsorbed by the suction nozzle to detect the deviation of the suction angle. The imaging of the parts.

In addition, a distance sensor 8 is attached to the mounting head 12. The distance sensor 8 measures the distance (height) in the Z direction between the suction nozzle and the circuit board 5 by the sensor light.

Moreover, the electronic component mounting apparatus 1 is provided with the nozzle exchanger 16 for replacing | exchanging a suction nozzle according to the size and shape of the component to adsorb | suck. In the nozzle exchanger 16, a plurality of nozzles are stored and managed.

In FIG. 2, the θ-axis rotation mechanism 20 includes a θ-axis motor 21 as a drive source for rotating the suction nozzle 12b about the nozzle shaft 12a of the mounting head 12. .

The drive pulley 22 is attached to the motor shaft 27 in the θ-axis motor 21. Driving the θ-axis motor 21 rotates a driven pulley (first driven pulley; 12c) mounted coaxially to the nozzle shaft 12a via a belt 23 spanning the drive pulley 22, thereby rotating the nozzle. The shaft 12a is supposed to rotate. In addition to the drive pulley 22 and the driven pulley 12c, the belt 23 also spans the pulley (second driven pulley; 24) for belt origin search, and at the time of driving the θ-axis motor 21, The pulley 24 also rotates through the belt 23 by the drive pulley 22.

Here, each pulley 22, 24, and 12c is a toothed pulley, as shown in FIG. 3, and the drive pulley 22 and the driven pulley 12c have the same tooth number m. The belt 23 is a toothed belt, and the number of teeth L of the belt 23 is equal to the minimum common multiple of the number of teeth m of the drive pulley 22 and the number p of teeth of the pulley 24. Is in agreement.

That is, the number of teeth L of the belt 23 is represented by the following equation using a function LCM () which derives the lowest common multiple.

L = LCM (m, p)... ... (One)

2, the θ-axis motor 21 has a motor encoder 25 built therein, and the motor angle of the θ-axis motor 21 can be detected from the output of the motor encoder 25. As shown in FIG. The motor encoder 25 outputs the Z phase as the first origin detection signal whenever the motor shaft 27 rotates once and the origin position becomes a predetermined reference position. Therefore, the home position of the drive pulley 22 can be detected by the motor encoder 25.

Further, the pulley 24 is provided with an origin sensor 26 capable of detecting the origin position of the pulley 24. The home sensor 26 outputs a signal corresponding to Z phase as the second home detection signal whenever the pulley 24 rotates once and the home position becomes a predetermined reference position. It can be configured by the sensor.

In the assembly installation of the θ-axis rotation mechanism 20, when the belt 23 is at the origin, initial adjustment is performed so that both the θ-axis motor 21 and the pulley 24 are at the origin. Here, the fact that the belt 23 is at the origin refers to a state where the origin position α of the belt 23 is at a predetermined reference position shown in FIG. 3, and both the θ-axis motor 21 and the pulley 24 are both. To be at the origin refers to a state in which both the origin position β of the θ-axis motor 21 and the origin position γ of the pulley 24 are both at the predetermined reference positions shown in FIG. 3. In addition, each reference position can be set suitably.

In the block diagram shown in FIG. 4, the electronic component mounting apparatus 1 is provided with the controller 30 which consists of a microcomputer provided with CPU, RAM, ROM, etc. which control the whole apparatus. The controller 30 controls each of the configurations 31 to 35 shown below.

The vacuum mechanism 31 generates a vacuum, and generates a negative pressure of vacuum to the suction nozzle 12b through a vacuum switch (not shown).

The X-axis motor 32 is a drive source for moving the mounting head 12 along the X-axis gantry 13 in the X-axis direction, and the Y-axis motor 33 moves the X-axis gantry 13 to the Y-axis gantry. A driving source for moving in the Y-axis direction along 14. The controller 30 drives the X-axis motor 32 and the Y-axis motor 33 to drive control, whereby the mounting head 12 is movable in the XY direction.

The Z-axis motor 34 is a drive source for raising and lowering the suction nozzle 12b in the Z direction. On the other hand, although only one Z-axis motor 34 is shown here, when a plurality of adsorption nozzles 12b are provided, the number of adsorption nozzles 12b is provided.

The controller 30 sucks the electronic component P using the suction nozzle 12b of the mounting head 12, and based on the image of the electronic component P captured by the recognition camera 7, the electronic component The component mounting process for mounting (P) on the circuit board 5 is performed. In addition, the controller 30 performs the belt origin search process shown in FIG. 5 at a predetermined timing (for example, when the power supply of the electronic component mounting apparatus 1 is ON), and searches for the origin of the belt 23. To perform the homing.

Since the θ-axis rotation mechanism 20 has the above formula (1), when the belt 23 is at the origin and returns to the origin for one week, the driving pulley 22 is L / m times and the pulley ( 24) rotates L / p times to return to the origin, respectively. The driving pulley 22 and the pulley 24 are both at the origin only when the belt 23 is at the origin. That is, when the belt 23 is displaced from the origin, the pulley 24 is in a state displaced from the origin even when the drive pulley 22 is at the origin.

Therefore, in such a belt origin search process, the drive pulley 22 and the pulley 24 are searched for in the belt origin search process while the? When the state of 24 is all confirmed at the origin, the rotation of the θ-axis motor 21 is stopped at that time. In this way, the belt 23 is returned to the origin.

In the belt origin search process, as shown in FIG. 5, first, in step S1, the controller 30 rotates the θ-axis motor 21 in a constant direction (for example, in a positive direction) and proceeds to step S2.

In step S2, the controller 30 determines whether or not the X phase of the motor encoder 25 has been detected. When the Z phase is detected, the process proceeds to step S3. When the Z phase is not detected, the θ-axis motor 21 is rotated until the detection is performed, and the process proceeds to the step S1.

In step S3, the controller 30 increments the counter n, which counts the number of times the motor encoder 25 has detected an abnormal phase after starting execution of the belt origin search process, and proceeds to step S4.

In step S4, the controller 30 checks the state of the home sensor 26 to determine whether the home sensor 26 is in an ON state (state of outputting a Z phase). When the home sensor 26 is in the ON state, it is determined that both the drive pulley 22 and the pulley 24 are at the home position, and the flow proceeds to step S5. When the home sensor 26 is in the OFF state, the following description will be made. The process proceeds to step S6.

In step S5, the controller 30 assumes that the search for the belt origin has succeeded and stops the rotation of the θ-axis motor 21, and sets the current state of the belt 23 as the state where the belt 23 is at the origin. Then, the belt home search process ends.

In addition, in step S6, the controller 30 determines whether the counter n has reached the predetermined value N. FIG. Here, the predetermined value (N) is for determining whether the belt 23 is one round after starting execution of the belt origin search process, and the number of teeth L of the belt 23 and the driving pulley 22 are determined. Determined by the ratio of the number of teeth (m). Specifically, the drive pulley 22 is rotated by L / m when the belt 23 is circumferential, so that N = L / m. When it is determined in step S6 that the counter n has not reached the predetermined value N, the process proceeds to the step S1 and when it is determined that the counter n has reached the predetermined value N. The flow proceeds to step S7.

In step S7, the controller 30 assumes that the belt origin cannot be searched even if the belt 23 is one week, and performs a predetermined error process such as reporting this to an operator, thereby ending the belt origin search process. Here, as a cause of the belt home search error, a failure of the sensor unit or failure of initial adjustment may be considered.

In the above configuration, when the motor shaft 27 is rotated up to N (= L / m) in the normal case, the origin of the belt 23 can be found and home return can be performed.

On the other hand, in the above, the motor encoder 25 corresponds to the first origin detection means, and the origin sensor 26 corresponds to the second origin detection means. In addition, step S1-S4 of FIG. 5 correspond to a search means, and step S5 corresponds to a motor stop means.

(action)

Next, the operation of the first embodiment will be described with reference to FIGS. 6 to 8. Here, the number of teeth (m) of the drive pulley 22 = 24, the number of teeth p of the pulley 24 for belt origin search 24 = 21, and the number of teeth L of the belt 23 = 168 will be described. .

The number of teeth m of the drive pulley 22 and the number L of teeth of the belt 23 are largely determined according to the environment to be used. For this reason, when designing the (theta) axis | shaft rotation mechanism 20, it is made to guide | induce the tooth number p which satisfy | fills said Formula (1) based on the tooth number m and tooth number L. In the case of m = 24 and L = 168, any of 7,14,21,28,42,56,84 can be selected as calculation of the tooth number p of the pulley 24.

Therefore, although p = 21 is demonstrated here, other values can also be selected arbitrarily from the said some value. On the other hand, the number p of teeth satisfying the above formula (1) includes p = 168 in calculation, but cannot be actually included because it is equal to the number of teeth L of the belt 23. For this reason, p = 168 is not selectable.

As shown in FIG. 7 (a), FIG. 6 unfolds and shows the belt which normally has a loop shape in one dimension as shown in FIG. In addition, the inverse triangular mark ((circle)) in FIG.7 (a) and (b) has shown the same point on a belt.

As shown in FIG. 6, when m = 24, L = 168, and p = 21, when the belt 23 is one round, the motor shaft 27 rotates L / m = 7, and the motor encoder 25 is Z The phase is output seven times (A) to (G). Similarly, when the belt 23 is one round, the pulley 24 rotates L / p = 8, and the origin sensor 26 outputs Z phase eight times (a) to (h).

In addition, as described above, the number of teeth L of the belt 23 corresponds to the minimum common multiple of the number of teeth m of the drive pulley 22 and the number of teeth p of the pulley 24. When 23) is at the origin, the driving pulley 22 and the pulley 24 are initially adjusted so that both are at the origin. For this reason, the timing of outputting the Z phase from the motor encoder 25 and the timing of outputting the Z phase from the origin sensor 26 coincide only when the belt 23 is at the origin.

From L / m = 168/24 = 7, the state of the belt 23 when the Z-phase is output from the motor encoder 25 is considered to be seven states of Figs. Here, Fig. 8 (a) shows a state in which the belt 23 is at the origin, and Figs. 8 (b) to 8 (g) show that the belt 23 is 1/7, 2/7,... , 6/7 weeks.

That is, Fig.8 (a)-(g) is the state of the belt 23 at the time when the Z phase (A)-Z phase G in FIG. 6 was detected, respectively. 8 (a) to 8 (g), the point α is the home position of the belt 23, the point β is the home position of the driving pulley 22, and the point γ is the pulley 24. Indicates the home position of.

When execution of the belt origin search process shown in FIG. 5 is started, the controller 30 first rotates the θ-axis motor 21 to detect the Z phase of the motor encoder 25. When the detected Z phase is Z phase B of FIG. 6, the state of the belt 23 at that time is a state which progressed by 1/7 week from the origin as shown in FIG. In addition, the pulley 24 is also in the state which advanced 1/7 weeks from an origin at this time.

In this way, the shift amount from the origin of the belt 23 and the shift amount from the origin of the pulley 24 coincide. When the belt 23 is at the origin, the pulley 24 is also at the origin. Thus, when both the driving pulley 22 and the pulley 24 are at the origin, the belt 23 is at the origin. Therefore, it is checked whether the pulley 24 is also at the origin when the driving pulley 22 is at the origin.

When the state when the drive pulley 22 is detecting the origin, that is, the Z phase of the motor encoder 25 is a state shown in Fig. 8B, the pulley 24 is not at the origin, so the origin sensor 26 ) Is OFF. Therefore, the controller 30 rotates the θ-axis motor 21 again until it detects the Z phase of the motor encoder 25 again. As shown in Fig. 8 (c), when the belt 23 is in the state of traveling by 2/7 weeks from the origin, and the motor encoder 25 outputs the Z phase C of Fig. 6, the controller ( 30 confirms the state of the origin sensor 26 at that time. However, even in this state, since the pulley 24 is in the state of traveling 2/7 weeks from the origin and the origin sensor 26 is in the OFF state, the controller 30 detects the Z phase of the motor encoder 25 again. The θ-axis motor 21 is rotated one time until it is (FIG. 8 (d)).

In addition, as shown in FIGS. 8E and 8F, the motor shaft 27 is rotated by one rotation to advance the belt 23 by 1/7 weeks, and the state of the origin sensor 26 is checked every time. To check whether the pulley 24 is at the origin (belt 23 is at the origin).

Then, as shown in Fig. 8 (g), when the belt 23 moves 6/7 weeks from the origin, the θ-axis motor 21 is rotated once until the Z phase of the motor encoder 25 is detected. As shown in Fig. 8A, the state of the belt 23 returns to the state at the origin, and the pulley 24 also returns to the origin. For this reason, the home sensor 26 at this time will be in an ON state. Therefore, the controller 30 stops the rotation of the θ-axis motor 21 at this point in time. As a result, the belt 23 returns to the origin.

In this embodiment, even if the belt 23 is in any position at the start of execution of the belt origin search process, the θ-axis motor 21 is rotated to a position where the Z phase of the motor encoder 25 is detected. The state of (23) always becomes either of FIG. 8 (a)-(g). Therefore, using this point, the belt 23 can be returned to the origin by rotating the motor shaft 27 at maximum N revolutions (7 revolutions in the above example).

(effect)

As described above, in the first embodiment, the number of teeth of the belt connecting the shaft of the suction nozzle and the motor shaft is made to match the minimum common multiple between the number of teeth of the drive pulley and the number of teeth of the belt origin search pulley. While the belt is in one week, the timing at which both the driving pulley and the belt origin search pulley coincide at the origin can be set only once. Since the timing at which the origin of the driving pulley coincides with the origin of the belt origin search pulley coincides with the timing at which the belt is at the origin, the θ-axis rotation mechanism is assembled and installed so that the origin of the driving pulley and the belt origin search can be performed. By searching the timing at which the origin of the pulley coincides, the origin of the belt can be searched.

The number of teeth of the motor shaft and the length of the belts vary depending on the system.If the number of teeth of the belt satisfies the condition that is an integer multiple of the number of teeth of the motor shaft, by adjusting the number of teeth of the belt homing pulley, Also available at. Moreover, the number of teeth of the belt origin search pulley can be obtained by simple calculation, and a good configuration can be arbitrarily selected.

When the belt origin is searched for, the Z phase output by the motor encoder of the θ-axis motor is detected, and the θ-axis motor is rotated by one rotation in a predetermined direction based on the point of time when the Z phase is detected. Check the state of the home sensor that detects the home position of the belt home search pulley each time. When it is confirmed from the state of the home sensor that the belt home search pulley is at the home position, the rotation of the θ-axis motor is stopped at that time. This makes it possible to reliably perform the home position return of the belt.

That is, the origin return of the belt can be performed without displaying the belt mark as in the conventional method. Therefore, even if aged deterioration or friction of the belt occurs, the search accuracy of the belt origin is not affected, and the belt return to the origin can be stably performed. As a result, stable mounting can be established.

Moreover, the origin sensor which detects the origin of the belt origin search pulley can be applied in what kind of structure, as long as it knows the origin (Z phase) of 1 week of the said pulley. Therefore, it is not necessary to know the detailed angle of the pulley, so that an inexpensive sensor can be used.

(Modified example)

In addition, in the said 1st Embodiment, although the case where only one pulley for belt origin search was provided was demonstrated, you may provide it in multiple numbers. For example, when the number of teeth L of the belt 23 is 144 and the number of teeth m of the driving pulley 22 is 24, the number of teeth p satisfying the above expression (1) is the belt 23. There is no other than 144, such as the number of teeth (L). Since it is impossible to include the pulley for the belt origin search with the number of teeth (p) = 144 in the θ-axis rotation mechanism 20 with the number of teeth (L) = 144, in this case, a plurality of pulleys for the belt origin search are provided. It is realized by installation.

That is, as shown in the following equation, the minimum common multiple between the number of teeth m of the drive pulley 22 and the number of teeth p1,..., Pk of the pulley for plural (k) belt origin search, The number of teeth L of the belt 23 is equal to that.

L = LCM (m, p1, ..., pk)... ... (2)

For example, in the above example (L = 144, m = 24), as shown in Fig. 9, two pulleys for belt origin search are provided, and the number of teeth (p1, p2) of these two pulleys is (16). , 18). On the other hand, in the example shown in Fig. 9, (p1, p2) = (16,18), but (p1, p2) satisfying the above formula (2) is (9,16), (9) in calculation. (48), (16,18), (16,36), (18,48), (16,72), (36,48), (48,72). Therefore, (p1, p2) can be arbitrarily selected from the above.

When a plurality of pulleys for belt origin search are provided, an origin sensor is provided in each of them, and in step S4 of the belt origin search process shown in Fig. 5, it is determined whether all the origin sensors are in the ON state. By this structure, the effect similar to the case where only one pulley for belt origin search is provided can be acquired.

(Second Embodiment)

Next, a second embodiment of the present invention will be described.

In the second embodiment described above, in the first embodiment described above, an angle sensor (pull angle detection means) capable of detecting the rotation angle of the pulley 24 is provided in place of the origin sensor 26.

(Configuration)

The θ-axis rotation mechanism 20 according to the present embodiment includes an angle sensor that can detect the rotation angle of the pulley 24 instead of the origin sensor 26 in FIG. 2. Then, the controller 30, in the belt origin search process, is based on the rotation angle of the pulley 24 at the point of time when the X-phase of the motor encoder 25 is detected, and the origin of the belt 23 at that point in time. The shift of the axial axis motor 21 is detected by detecting a deviation amount from the gap and making the deviation amount equal to zero.

10, the belt origin search processing procedure of the second embodiment will be described.

First, in step S11, the controller 30 rotates the θ-axis motor 21 in a predetermined direction (for example, in a forward direction), and the process proceeds to step S12.

In step S12, the controller 30 determines whether the Z phase of the motor encoder 25 has been detected. When the Z phase is detected, the process proceeds to Step S13. When the Z phase is not detected, the θ-axis motor 21 is rotated until it is detected, and the process proceeds to the step S11.

In step S13, the controller 30 acquires the rotation angle of the pulley 24 detected by the angle sensor, and proceeds to step S14.

In step S14, the controller 30 determines whether the origin of the belt 23 can be searched based on the rotation angle of the pulley 24 obtained in step S13.

When the above-described initial adjustment is made, there is a certain law in the rotation angle of the pulley 24 at the time when the Z phase of the motor encoder 25 is detected, and the angle is the number of teeth (m) of the driving pulley 22. And the number p of teeth of the pulley 24 are determined. Then, knowing the rotation angle of the pulley 24 at the time point when the Z phase of the motor encoder 25 is detected, it can be known how far the belt 23 is shifted from the origin. This point will be described in detail with reference to FIG. On the other hand, FIG. 11 is an image diagram in which one round of the belt 23 is unfolded in one dimension. That is, as shown to Fig.7 (a), the belt which is normally loop-shaped is shown to expand one-dimensionally, as shown to Fig.7 (b).

In the example shown in FIG. 11, the tooth number m of the drive pulley 22 = 24, the tooth number p of the pulley 24 = 21, and the tooth number L of the belt 23 = 168. The rotation angle of the pulley 24 at the time of detecting the Z phase of the motor encoder 25 is 0 degrees at the time of detecting the Z phase A (belt origin). Then, 360 ° / 7 × 51 ° at the detection of the Z phase (B), 360 ° / 7 × 2 × 103 ° at the detection of the Z phase (C), 360 ° / at the detection of the Z phase (D) 7 × 3 ≒ 154 °, 360 ° / 7 × 4 ≒ 206 ° at detection of Z phase (E), 360 ° / 7 × 5 ≒ 257 ° at detection of Z phase (F), Z phase (G) Is detected at 360 ° / 7 × 6 × 309 °.

Therefore, when the rotation angle of the pulley 24 detected by the angle sensor at the time when the Z phase of the motor encoder 25 is detected, for example, 51 degrees, it is understood that the detected Z phase is the Z phase B of FIG. Can be. Therefore, in this case, since the belt 23 is shifted by 1/7 weeks in the forward direction, the belt 23 can be returned to the origin by rotating the motor shaft 27 for one week in the reverse direction. It can be seen.

Therefore, in step S14, the rotation angle of the pulley 24 acquired in the said step S13 is determined by the ratio of the tooth number m of the drive pulley 22 and the tooth number p of the pulley 24, The belt It is determined whether or not the origin of (23) is a searchable angle. For example, in the example of FIG. 11, when the rotation angle of the pulley 24 is an angle which provided the allowable range (+/- several degrees) by j times (j is an integer of 1 or more and 7 or less) of 360 degrees / 7, the belt 23 Is determined to be the searchable angle. When it is determined that the origin of the belt 23 is searchable, the process proceeds to step S15.

In step S15, the controller 30 obtains the amount of deviation from the origin of the belt 23 through the rotation angle of the pulley 24 obtained in the step S13, and θ required to return the belt 23 to the origin in the shortest path. The rotation direction and the rotation amount of the shaft motor 21 are calculated.

For example, in the example shown in FIG. 11, when the rotation angle of the pulley 24 is 0 degrees, since the belt 23 is at the origin, it is assumed that the θ-axis motor 21 does not need to be rotated. 0. On the other hand, when the rotation angle of the pulley 24 is 51 degrees, since the phase Z is detected, the θ-axis motor 21 is rotated one direction in the reverse direction to return the belt 23 to the origin in the shortest path. The rotation direction is reversed and the rotation amount is 360 degrees. Similarly, when the rotation angle of the pulley 24 is 103 °, it is necessary to rotate the θ-axis motor 21 in the reverse direction, and the rotation direction is reverse and the rotation amount is 720 °. Furthermore, when the rotation angle of the pulley 24 is 154 °, it is necessary to rotate the θ-axis motor 21 three directions in the reverse direction. The rotation direction is set in the reverse direction and the rotation amount is set to 1080 degrees.

In addition, when the rotation angle of the pulley 24 is 154 degrees, in order to return the belt 23 to the origin at the shortest path, it is necessary to rotate the θ-axis motor 21 three times in the forward direction. In the forward direction, the amount of rotation is 1080 °. And when the rotation angle of the pulley 24 is 206 degrees, it is necessary to make the (theta) shaft motor 21 rotate two directions forward, and the said rotation direction shall be a forward direction, and the said rotation amount shall be 720 degrees. Similarly, when the rotation angle of the pulley 24 is 309 degrees, it is necessary to rotate the (theta) shaft motor 21 one direction forward, and the said rotation direction shall be a forward direction, and the said rotation amount shall be 360 degrees.

Here, the determination of the rotation angle of the pulley 24 is performed in consideration of the allowable range. That is, for example, when the detected value detected by the angle sensor is 0 ° ± permissible range, when the rotation angle of the pulley 24 is 0 ° and the detected value detected by the angle sensor is 51 ° ± permissible range, Assuming that the rotation angle of the pulley 24 is 51 °, the rotation direction and rotation amount of the θ-axis motor 21 are calculated.

Next, in step S16, the controller 30 rotates the θ-axis motor 21 in the rotational direction obtained in the step S15 by the amount of rotation obtained in the step S15, and proceeds to step S17.

In step S17, when the rotation of the (theta) -axis motor 21 complete | finished, the controller 30 assumes that origin return of the belt 23 is complete, and complete | finishes a belt origin search process.

If it is determined in step S14 that the belt origin cannot be searched, the process proceeds to step S18, and the controller 30 performs predetermined error processing such as reporting to the operator that the belt origin cannot be searched. The belt origin search process ends. Here, as a cause of the belt origin search error, a failure of the sensor unit or failure of initial adjustment may be considered.

On the other hand, steps S11 to S14 in FIG. 10 correspond to the shift amount calculating means, step S15 corresponds to the motor control amount calculating means, and step S16 corresponds to the motor driving means.

(action)

Next, the operation of the second embodiment will be described. Here, as shown in FIG. 11, the number of teeth (m) of the drive pulley 22 = 24, the number of teeth (p) of the pulley 24 for belt origin search = 21, and the number of teeth (L) of the belt 23 It demonstrates using the example of = 168.

When execution of the belt origin search process shown in FIG. 10 is started, the controller 30 first rotates the θ-axis motor 21 to detect the Z phase of the motor encoder 25. Then, the rotation angle of the pulley 24 at that time is detected by the angle sensor.

At this time, if it is detected by the angle sensor that the rotation angle of the pulley 24 is 51 °, since the angle is an angle that can be searched for the belt origin, the controller 30 is based on the detected angle to the origin of the belt 23 The direction of rotation and the amount of rotation of the θ-axis motor 21 necessary for returning to are calculated.

Since the rotation angle of the pulley 24 is 51 degrees, the controller 30 has the state of the belt 23 progressing 1/7 weeks in the forward direction when the Z phase of the motor encoder 25 is detected. It is judged to be in a state. For this reason, when the motor shaft 27 is rotated once in the reverse direction, it is determined that the belt 23 can be returned 1/7 weeks in the reverse direction, and the belt 23 can be returned to the origin in the shortest path. Therefore, the controller 30 sets the rotation direction in the reverse direction and the rotation amount to 360 ° for one week, thereby rotating the θ-axis motor 21 by 360 ° in the reverse direction. As a result, the belt 23 returns to the origin.

As described above, by detecting the rotation angle of the pulley 24 at the time when the Z phase of the motor encoder 25 is detected, the amount of deviation from the origin of the belt 23 is determined, and then the θ-axis motor 21 ), Rotate the amount of rotation required for homing at once. Therefore, after detecting the Z phase of the motor encoder 25, it can return to origin quickly, without rotating the (theta) -axis motor 21 several times.

In addition, in this embodiment, although the case where only one pulley for belt origin search is provided was demonstrated, it is applicable also when it installs in multiple numbers as shown, for example in FIG.

(effect)

Thus, in the said 2nd Embodiment, since the angle sensor which detects the present angle of the belt origin search pulley is provided, from the angle of the pulley at the time of detecting the Z phase of a motor encoder, the belt at that time is The state of (deviation amount from the origin) can be recognized. For this reason, after detecting the Z phase of a motor encoder, a belt can be returned to origin at once. Therefore, the belt can be returned to the origin without having to repeat N times (L / m times) as in the first embodiment described above. As a result, the time required for home position return can be shortened.

In addition, after detecting the Z phase of the motor encoder, the rotation direction and the rotation amount of the θ-axis motor are calculated to return to the home position in the shortest path, so that home return can be performed more quickly.

(Third Embodiment)

Next, a third embodiment of the present invention will be described.

In the third embodiment, in the second embodiment described above, the position of the current belt 23 is determined based on the rotation angle of the pulley 24 at the time when the Z phase of the motor encoder 25 is detected. On the contrary, the current position of the belt 23 is determined based on the rotation angle of the θ-axis motor 21 at the time when the Z phase of the origin sensor 26 provided in the pulley 24 is detected. .

(Configuration)

The θ-axis rotation mechanism 20 in the present embodiment has the same configuration as the θ-axis rotation mechanism 20 shown in FIG. 2. Then, the controller 30 acquires the rotation angle of the θ-axis motor 21 at the point of time when the Z-phase of the origin sensor 26 is detected in the belt origin search process, and at that time based on the acquired angle. The shift amount from the origin of the belt 23 is detected.

12, the belt origin search processing procedure of the third embodiment will be described.

First, in step S21, the controller 30 rotates the θ-axis motor 21 in a constant direction (for example, in a forward direction) and proceeds to step 22. FIG.

In step S22, the controller 30 determines whether or not the Z phase of the motor encoder 25 has been detected. When the Z phase is detected, the process proceeds to Step S23. When the Z phase is not detected, the θ-axis motor 21 is rotated until it is detected.

In step S23, the controller 30 checks the state of the home sensor 26 to determine whether the home sensor 26 is in the ON state. When the home sensor 26 is in the OFF state, the process proceeds to Step S24. When the home sensor 26 is in the ON state, the process proceeds to Step S27 described later.

In step S24, the controller 30 determines whether the search for the belt origin has failed. Here, after detecting the Z phase of the motor encoder 25, it is determined whether or not the θ-axis motor 21 is rotated by the angle at which the Z phase of the origin sensor 26 is theoretically detected. For example, when the number of teeth m of the drive pulley 22 is greater than the number of teeth p of the pulley 24, the Z phase of the origin sensor 26 is at least rotated while rotating the θ-axis motor 21 by 360 degrees. It can be detected once. Therefore, in such a case, after detecting the Z phase of the motor encoder 25, it is determined whether the θ-axis motor 21 is rotated 360 degrees, and when it is rotated 360 degrees, it is determined that the search for the belt origin has failed. do.

If it is determined in step S24 that the search for the belt origin has failed, the process proceeds to step S25, and a predetermined error process is performed such as reporting to the operator that the search for the belt origin has failed, and the belt origin search process ends. do. Here, as a cause of the belt origin search error, a failure of the sensor unit or failure of initial adjustment may be considered.

On the other hand, in step S24, if it is not determined that the search for the belt origin has failed, the process proceeds to step S26, in which the controller 30 rotates the θ-axis motor 21 in a predetermined angle (θ ₀ °) in the forward direction and performs the step. Go to S23. Here, the predetermined angle θ ₀ is determined based on the ratio of the number of teeth m of the drive pulley 22 to the number of teeth p of the pulley 24.

In the example shown in FIG. 13, the number of teeth m of the drive pulley 22 is 24, the number of teeth p of the pulley 24 is 21, and the number of teeth L of the belt 23 is 168. When the above initial adjustment is made, the motor encoder output becomes 0 ° at the time of detecting the Z phase a of the home sensor 26 (belt origin). 315 ° at the detection of the Z phase (b), 270 ° at the detection of the Z phase (c), 225 ° at the detection of the Z phase (d), 180 ° at the detection of the Z phase (e), 135 degrees at the time of detection of Z phase (f), 90 degrees at the time of detection of Z phase (g), and 45 degrees at the time of detection of Z phase (h). As described above, when the ratio of the number of teeth m and the number of teeth p is 8: 7, the motor encoder output at the time of detecting the Z phase of the origin sensor 26 is a multiple of 45 °.

Therefore, in the example shown in FIG. 13, when the θ-axis motor 21 is rotated forward by 45 ° based on the point in time when the Z phase of the motor encoder 25 is detected, the Z phase of the motor encoder 25 is again. Before detecting this, it is necessary to coincide with the timing of detecting the Z phase of the origin sensor 26 somewhere. For this reason, in this case, the predetermined angle θ ₀ = 45 ° and whenever the θ-axis motor 21 is rotated in the 45 ° forward direction, whether the home sensor 26 reacts (turns on) Check it. This operation is repeated until the home sensor 26 reacts, and when the motor encoder output when the home sensor 26 reacts is acquired, the motor encoder output from the origin of the belt 23 at that time is obtained. The amount of misalignment can be grasped.

In step S27, the controller 30 obtains the motor angle from the output of the motor encoder 25, and the process proceeds to step S28.

In step S28, the controller 30 obtains the amount of deviation from the origin of the belt 23 through the motor angle obtained in step S27, and the θ-axis motor 21 required to return the belt 23 to the origin in the shortest path. Calculate the rotation direction and amount of rotation.

For example, in the example shown in FIG. 13, when the motor angle is 0 degrees, since the belt 23 is at the origin, it is assumed that the θ-axis motor 21 does not need to be rotated and the rotation amount is zero. In addition, when the motor angle is 315 °, since the Z phase b is in a detected state, the θ-axis motor 21 needs to be rotated 315 ° in the reverse direction in order to return the belt 23 to the origin in the shortest path. Let the said rotation direction be reverse, and let the said rotation amount be 315 degrees. Similarly, when the motor angle is 270 °, it is necessary to rotate the θ-axis motor 21 in the reverse direction 360 ° + 270 °, and the rotation direction is reversed, and the rotation amount is 630 °. In addition, when the motor angle is 225 °, it is necessary to rotate the θ-axis motor 21 in the reverse direction by 720 ° + 225 °, and the rotation direction is reversed, and the rotation amount is 945 °.

In addition, when the motor angle is 180 degrees, since the Z phase e is in a detected state, it is necessary to rotate the θ-axis motor 21 in the forward direction 1080 ° + 180 ° in order to return the belt 23 to the origin. It is assumed that the rotational direction is in the forward direction and the rotational amount is 1260 °. On the other hand, when the motor angle is 180 degrees, the rotation direction may be reversed and the rotation amount may be 1260 degrees.

In addition, when the motor angle is 135 °, the Z phase f is in a detection state. Therefore, in order to return the belt 23 to the home position in the shortest path, the θ-axis motor 21 is 720 ° + (360 ° in the forward direction). -135 degrees), the rotation direction is set to the forward direction, and the rotation amount is set to 945 degrees. Similarly, when the motor angle is 90 °, the θ-axis motor 21 needs to be rotated 360 ° + (360 ° -90 °) in the forward direction, and the rotation amount is reversed, and the rotation amount is 630. Let it be °. In addition, when the motor angle is 45 °, it is necessary to rotate the θ-axis motor 21 in the forward direction (360 ° -45 °), and the rotation direction is in the forward direction, and the rotation amount is 315 °. .

Here, the determination of the motor angle is performed in consideration of a predetermined allowable range (± several degrees). That is, for example, when the detected value detected by the motor encoder 25 is within the allowable range of 315 ° ±, the motor angle is 315 ° when the detected value detected by the motor encoder 25 is within the allowable range of 270 ° ±. The angle is set to 270 ° and the rotation direction and the rotation amount of the θ-axis motor 21 are calculated.

Next, in step S29, the controller 30 rotates the θ-axis motor 21 in the rotational direction obtained in the step S28 by the amount of rotation obtained in the step S28, and proceeds to step S30.

In step S30, the controller 30 assumes that the homing of the belt 23 has been completed at the time when the rotation of the θ-axis motor 21 is finished, and the belt origin searching process ends.

On the other hand, in the above, the motor encoder 25 corresponds to the motor angle detecting means. In addition, step S21-S27 of FIG. 2 respond | corresponds to a shift amount calculation means, step S28 corresponds to a motor control amount calculation means, and step S29 corresponds to a motor drive means.

(action)

Next, the operation of the third embodiment will be described. Here, as shown in FIG. 13, the number of teeth (m) of the drive pulley 22 = 24, the number of teeth (p) of the pulley 24 for the belt origin search = 21, and the number of teeth (L) of the belt 23 It demonstrates using the example of = 168.

When execution of the belt origin search process shown in FIG. 12 is started, the controller 30 first rotates the θ-axis motor 21 to detect the Z phase of the motor encoder 25. From this point in time, the θ-axis motor 21 is rotated in the forward direction by a predetermined angle θ ₀ , and it is checked whether or not the origin sensor 26 reacts every time.

For example, in the example shown in FIG. 13, when the θ-axis motor 21 is rotated to detect the Z phase of the motor encoder 25 in a state where the belt 23 slightly advances from the origin, the belt at that time Reference numeral 23 shows a state of 1/7 weeks in the forward direction. In this state, when the θ-axis motor 21 is rotated in the forward direction by a predetermined angle (θ ₀ ) = 45 °, the Z phase of the origin sensor 26 is rotated at the time when the θ-axis motor 21 is rotated six times. (c) is detected. That is, the motor encoder output at this time is 45 ° x 6 = 270 °.

When it is detected that the rotational angle of the θ-axis motor 21 at the time point of detecting the i-phase c of the origin sensor 26 is 270 °, the controller 30 determines the belt 23 based on the detected angle. The rotational direction and amount of rotation of the θ-axis motor 21 necessary to return to the origin are calculated.

Since the rotation angle of the θ-axis motor 21 is 270 °, when the controller 30 rotates the θ-axis motor 21 in the reverse direction 360 ° + 270 ° = 630 °, the belt 23 is homed in the shortest path. I think it can be returned to. Therefore, the controller 30 sets the rotation direction in the reverse direction, the rotation amount to 630 °, and rotates the θ-axis motor 21 in the reverse direction 630 °. As a result, the belt 23 returns to the origin.

As described above, the θ-axis motor 21 is rotated by a predetermined angle θ ₀ from the time point when the Z phase of the motor encoder 25 is detected, and the reaction of the origin sensor 26 is confirmed, and the origin sensor 26 is checked. By detecting the rotation angle of the θ-axis motor 21 at the time when the Z phase is detected, the shift amount from the origin of the belt 23 is grasped. In addition, at the time of detecting the Z phase of the motor sensor 25 at the time of detecting the Z phase of the origin sensor 26, the number of teeth m of the driving pulley 22 and the pulley 24 are driven by the θ-axis motor 21. ) Rotates by a predetermined angle (θ ₀ ) determined according to the ratio between the number of teeth p of.

Thereby, it can be made to confirm whether the origin sensor 26 actually reacts in the belt position where the origin sensor 26 may react. Therefore, even if the reaction angle (origin detectable range) of the home sensor 26 has a predetermined width, and the structure of the home sensor 26 reacts even if the pulley 24 is slightly shifted from the home position, good accuracy is obtained. It is possible to detect that the low pulley 26 is at the origin.

After detecting the Z phase of the home sensor 26, the θ-axis motor 21 is rotated at one time by the amount of rotation necessary for the home position return. Therefore, after detecting the Z phase of the origin sensor 26, it can return to origin quickly without rotating the (theta) -axis motor 21 several times.

In addition, in this embodiment, although the case where only one pulley for belt origin search is provided was demonstrated, it is applicable also when it installs in multiple numbers as shown, for example in FIG.

In addition, when the home sensor 26 has a structure in which only a pin point is detected without giving a width to the reaction angle (detectable range), the home sensor is referenced based on the point of time when the Z phase of the motor encoder 25 is detected. Instead of detecting the Z phase of (26), the Z phase of the origin sensor 26 may be detected while the θ-axis motor 21 is directly rotated immediately after the belt origin search process is started.

(effect)

As described above, in the third embodiment, the current position of the belt can be grasped based on the rotational angle of the θ-axis motor at the time when the origin of the belt origin search pulley is detected. It is not necessary to install an expensive angle sensor that can detect the rotation angle of the pulley only by installing an inexpensive origin sensor.

When the origin of the belt origin search pulley is detected, a method of confirming the response of the origin sensor is performed by rotating the θ-axis motor by a predetermined angle from the time when the Z phase of the motor encoder is detected. At this time, the predetermined angle is set according to the ratio between the number of teeth of the drive pulley and the number of teeth of the belt origin search pulley. This makes it possible to check whether the home sensor actually reacts only at the belt position where the home sensor may react, so that the belt home search pulley can be precisely performed regardless of the reaction angle (origin detection range) of the home sensor. The origin of can be detected.

After the current position of the belt is determined based on the rotational angle of the θ-axis motor at the point of time when the origin of the belt origin search pulley is detected, it is possible to return the belt to the origin at once. It can shorten the time required.

(Application example)

In addition, in the said 2nd and 3rd embodiment, when the belt 23 is at the origin, when the drive pulley 22 and the pulley 24 are made to perform initial adjustment and an assembly installation work is performed. Although it has been described, it can be realized without the initial adjustment.

The Z phase of the θ-axis motor 21 cannot be detected accurately unless the power is turned on and operated. In addition, when the θ-axis rotation mechanism 20 such as the belt 23 is assembled and installed, it is difficult to supply power to the θ-axis motor 21, and even if it is possible, the amount of work increases. Therefore, the work amount can be reduced by performing the assembly installation work without initial adjustment. At this time, it is necessary to operate in consideration that an offset (deviation) is added to the origin position of the driving pulley 22. However, if the offset value is taken into consideration for each detection angle, the operation is sufficiently possible.

For example, in the case of 2nd Embodiment mentioned above, it is assumed that the offset value (fixed value) is contained in the rotation angle of the pulley 24 detected by the angle sensor, and a belt origin search process is performed. For example, in the example shown in FIG. 11, the permissible range used for determination of the detection value of an angle sensor is set to +/- 25 degree.

Specifically, when the detected value of the angle sensor is 0 ° ± 25 ° (335 ° to 25 °), the rotation angle of the pulley 24 is assumed to be 0 °, and it is determined that the belt 23 is at the origin. . When the detected value of the angle sensor is 51 ° ± 25 ° (26 ° to 76 °), the rotation angle of the pulley 24 is assumed to be 51 °, and the belt 23 advances 1/7 weeks from the origin. It is judged that it is in one state (a detection state of Z phase B).

Similarly, when the detection value of the angle sensor is 103 ° ± 25 ° (78 ° to 128 °), the rotation angle of the pulley 24 is 103 °, and the detection value of the angle sensor is 154 ° ± 25 ° (129 ° to 179). °), the rotation angle of the pulley 24 is 154 °, and when the detection value of the angle sensor is 206 ° ± 25 ° (181 ° to 231 °), the rotation angle of the pulley 24 is 206 ° and the angle sensor When the detected value is 257 ° ± 25 ° (232 ° to 282 °), the rotation angle of the pulley 24 is 257 °, and the detection value of the angle sensor is 309 ° ± 25 ° (284 ° to 334 °). It is assumed that the rotational angle of the pulley 24 is 309 °.

Here, the allowable range of "± 25 °" is determined based on the ratio of the number of teeth (m) of the driving pulley 22 and the number of teeth (p) of the pulley 24, and m: p = 7: Since it is 8, it becomes a value which coincides or nearly coincides with half of 51 degrees.

In addition, at this time, the offset value of the drive pulley 22 can be detected through the shift | deviation amount from the theoretical value (0 degree, 51 degree, 103 degree etc. in the example of FIG. 11) of the detection value of an angle sensor. Therefore, the offset value once detected is stored and used as the offset value (reference value) after the next time. As a result, the belt origin search process can be performed more appropriately.

In the third embodiment described above, it is assumed that the offset value (fixed value) is included in the motor encoder value (angle) of the θ-axis motor 21, and the belt origin search process is performed. That is, in the example shown in FIG. 13, the permissible range used for the determination of the motor angle is ± 22 °.

Specifically, when the motor encoder output is 0 ° ± 22 °, the motor encoder output is assumed to be 0 °, and it is determined that the belt 23 is at the origin. In addition, when the motor encoder output is 315 ° ± 22 °, the motor encoder output is 315 °, and the belt 23 is in a state (1 phase detected state of Z phase b) 1/8 week from the origin. To judge.

Similarly, if the motor encoder output is 270 ° ± 22 °, the motor encoder output is 270 °, and if the motor encoder output is 225 ° ± 22 °, the motor encoder output is 225 ° and the motor encoder output is 180 ° ± 22 °. If the motor encoder output is 180 °, if the motor encoder output is 135 ° ± 22 °, if the motor encoder output is 135 °, if the motor encoder output is 90 ° ± 22 °, the motor encoder output is 90 ° and the motor encoder output. In the case of 45 ° ± 22 °, the motor encoder output is assumed to be 45 °.

Here, "± 22 °" which is an allowable range is determined based on the ratio of the number of teeth (m) of the drive pulley 22 to the number of teeth (p) of the pulley 24, and m: p = 7 in the above example. Since it is 8, the value coincides or almost coincides with half of 45 °. In this case, when the angle (predetermined angle θ ₀ ) for rotating the θ-axis motor 21 is set relatively small at about 5 ° in step S26 of FIG. 12, the response can be reliably obtained by the origin sensor 26. There is a number.

The predetermined angle θ _{0 in} this case can also be set in accordance with the reaction angle (detectable range) of the origin sensor 26. In general, the origin sensor is more difficult to detect a pin point without providing a width to the detectable range, and thus, the control is more difficult to attach. Therefore, (in the example shown in Figure _{13 θ TH,, m: p} = 7: 8 so 45 °) is the width of the reference value when a large (less than the stage, θ _TH × 2) than a predetermined angle (θ ₀₎ = Set to _TH . On the other hand, in the case of θ _TH or less, the predetermined angle θ ₀ is set to 1/2 or less of the width (angle) of the detectable range of the origin sensor 26. In the example shown in FIG. 13, since it does not shift more than 45 degrees (even if it shifts, since it corresponds to the Z phase of the next (theta) -axis motor 21, it does not become a shift | offset | difference), It is possible to operate suitably by said control. Become.

1: Electronic component mounting device
5: circuit board
11: conveying rail
12: mounting head
12a: nozzle shaft
12b: adsorption nozzle
12c: driven pulley (first driven pulley)
13: X axis gantry
14: Y axis gantry
15: parts supply device
16: nozzle changer
20: θ axis rotation mechanism
21: θ axis motor
22: driven pulley
23: belt
24: belt origin search pulley (second driven pulley)
25: motor encoder
26: home sensor
30: controller
31: vacuum apparatus
32: X axis motor
33: Y axis motor
34: Z axis motor

Claims (9)

The electronic component mounting apparatus which attracts an electronic component P by the adsorption nozzle 12b attached to the nozzle shaft 12a rotated by the θ-axis motor 21, and mounts the electronic component on the substrate 5. as,
A toothed drive pulley 22 mounted coaxially with the shaft on the shaft 27 of the θ-axis motor,
A toothed first driven pulley 12c mounted coaxially with the nozzle shaft to the nozzle shaft;
Second driven pulley 24 with teeth,
A toothed belt 23 spanning the drive pulley, the first driven pulley and the second driven pulley and having a tooth number equal to a minimum common multiple of the number of teeth of the drive pulley and the number of teeth of the second driven pulley; ,
First origin detection means 25 for outputting a first origin detection signal when the drive pulley is at the origin;
Second origin detection means 26 for outputting a second origin detection signal when the second driven pulley is at the origin;
An origin return means 30 for returning the belt to the origin based on the first origin detection signal output by the first origin detection means and the second origin detection signal output by the second origin detection means; Electronic component mounting apparatus characterized in that it comprises. The method of claim 1,
The second driven pulley is provided in plurality,
The second origin detection means outputs each second origin detection signal when each of the second driven pulleys is at the origin,
And the origin return means returns the belt to the origin based on the second origin detection signal output by the second origin detection means. 3. The method according to claim 1 or 2,
And the drive pulley and the second driven pulley are both assembled so as to be at the origin (β, γ) when the belt is at the origin (α). 3. The method according to claim 1 or 2,
The origin return means,
Search means (S1 to S4) for searching the timing at which the first origin detection means and the second origin detection means respectively output the origin detection signal while rotating the θ-axis motor;
And a motor stop means (S5) for stopping the rotation of the θ-axis motor at the timing searched by the search means. 3. The method according to claim 1 or 2,
And a pulley angle detecting means 26 for detecting a rotation angle of the second driven pulley,
The origin return means,
Based on the rotation angle of the second driven pulley detected by the angle detecting means when the first origin detecting means outputs the first origin detecting signal, the amount of deviation from the origin of the belt at that time is calculated. Shift amount calculation means (S11 to S14),
Motor control amount calculation means (S15) for calculating the rotational direction and the rotational amount of the θ-axis motor required to return the belt to the origin, based on the deviation amount from the origin of the belt calculated by the deviation amount calculation means; ,
And a motor driving means (S16) for rotating the θ-axis motor in the rotational direction calculated by the motor control amount calculating means by the amount of rotation calculated by the motor control amount calculating means. . 3. The method according to claim 1 or 2,
Motor angle detecting means (S25) for detecting the rotation angle of the θ-axis motor,
The origin return means,
Based on the rotation angle of the θ-axis motor detected by the motor angle detecting means when the second home detecting means outputs a second home detecting signal, the amount of deviation from the origin of the belt at that time is calculated. Shift amount calculation means (S21 to S27)
Motor control amount calculation means (S28) for calculating the rotational direction and the rotational amount of the θ-axis motor required to return the belt to the origin based on the displacement amount from the origin of the belt calculated by the displacement amount calculation means; ,
And a motor drive means (S29) for rotating the θ-axis motor in the rotational direction calculated by the motor control amount calculation means, by the amount of rotation calculated by the motor control amount calculation means. . The method according to claim 6,
The shift amount calculation means,
After detecting that the first origin detection means outputs the first origin detection signal, whether or not the second origin detection means outputs the second origin detection signal each time the θ-axis motor is rotated by a predetermined angle. And the deviation amount is calculated based on the rotation angle of the θ-axis motor detected by the motor angle detection means when it is confirmed that the second origin detection means outputs a second origin detection signal. Electronic component mounting apparatus. 8. The method of claim 7,
The predetermined angle is determined according to the ratio of the number of teeth (m) of the drive pulley and the number of teeth (p) of the second driven pulley. The method of claim 1,
A motor encoder capable of detecting the home position of the drive pulley, and an origin sensor capable of detecting the home position of the second driven pulley,
By the relationship between the home position of the drive pulley and the home position of the second driven pulley, the home position of the belt connecting the shaft of the suction nozzle and the shaft of the motor that rotates the suction nozzle is searched for, and the home return is performed. Electronic component mounting apparatus, characterized in that for performing.

Images