JP4342914B2 - Position detection device and single axis robot, surface mounter, component testing device, SCARA robot equipped with the same - Google Patents

Description

The present invention is a power failure, even if the power supply during a high speed rotation of the drive motor by disconnection or the like is cut off, position the rotational absolute positions of the drive motor Ru can be accurately detected with a置検detection apparatus and the apparatus The present invention relates to single-axis robots, surface mounters, component testing equipment, and SCARA robots.

  Conventionally, an XY table in which a table is moved two-dimensionally by two single-axis robots arranged orthogonally is widely known. This type of XY table has a wide application field, and is also applied to, for example, a so-called surface mounter that automatically mounts components on a printed circuit board.

  In this type of XY table, for example, a resolver is incorporated as a position detection means in the drive motor of each single-axis robot, and the position control of the table in the X-axis direction and the Y-axis direction is based on a response signal when the resolver is excited. For example, when a power failure occurs during driving and the power supply is cut off, the supply of excitation voltage to the resolver is cut off, and the rotational absolute position over multiple rotations of the motor (from the reference position) However, there is a problem that the drive motor rotates due to inertia and hinders subsequent position control. In order to solve this point, for example, a position detection device as disclosed in Patent Document 1 has been proposed.

This apparatus excites the resolver with a sine wave when the main power is on, and detects the absolute rotational position of the drive motor based on the detection of the induced voltage. When the main power is turned off (disconnected) due to a power failure or the like, the rotation amount of the drive motor (the number of rotations from the reference position) is calculated and stored based on the absolute rotation position at that time. During power interruption, the resolver is pulse-excited using a backup power source, and the rotational change amount of the drive motor is detected based on detection of the induced voltage, and the stored rotational amount is corrected. Thus, when the main power supply is restored, the rotation angle of the drive motor is obtained based on the output of the resolver, and the absolute rotation position of the drive motor is detected from the rotation angle and the stored rotation amount.
JP 63-214617 A

  According to the position detection device disclosed in Patent Document 1, the absolute position of rotation can be detected with high accuracy because the response signal from the resolver becomes a smooth sine wave by exciting the resolver with a sine wave during energization. There is an advantage that the consumption of the backup power supply can be reduced because the response signal from the resolver is obtained by performing the pulse excitation when the power is supplied.

  However, as described above, since the resolver is switched to pulse excitation after the occurrence of a power failure (power failure, etc.), the response signal from the resolver becomes an intermittent signal and the continuity of the signal before and after the power failure occurs is lost. There is a drawback in that an error is likely to occur in the rotation amount (correction value), and the reliability of the finally obtained absolute rotation position is not necessarily high. Thus, it is conceivable to increase the duty ratio of the excitation signal (pulse signal) or shorten the transmission cycle. However, this reduces the effect of reducing the consumption of the backup power supply, which is not a good idea. Therefore, it is desirable to solve this point.

  The present invention has been made in view of the circumstances as described above, and an object of the present invention is to improve the reliability of the absolute rotation position detected after the main power supply is restored while reducing the consumption of the backup power supply at the time of power interruption. It is said.

The position detection device of the present invention detects the absolute position of rotation of the rotating shaft over multiple rotations based on the output of the sine wave by sine wave excitation of the resolver of the rotating shaft to which the resolver is assembled. When the main power supply is cut off, the resolver is pulse-excited using a backup power supply to detect the amount of rotation of the rotating shaft based on the pulse output as the output, and after the main power supply is restored, this rotation An apparatus for detecting the rotational absolute position based on a rotation amount and a rotation angle of a rotating shaft detected based on the sine wave output, wherein the rotation angle of the rotating shaft is detected based on the sine wave output. and angular detecting means, Thailand when using sinusoidal excitation signal for exciting the resolver, absolute value of the sine wave output from the resolver by converting this signal has a peak A waveform shaping means for outputting a ring signal, a first data generation means for generating waveform output data corresponding to the rotation of the rotary shaft by the sample-hold in synchronism with the sine wave output to the timing signal from the resolver After the occurrence of power interruption, the pulse output from the resolver is sampled and held to generate waveform output data corresponding to the rotation of the rotary shaft, and the first and second data generation means A rotation amount detecting means for continuously detecting the rotation amount of the rotating shaft before and after the occurrence of power interruption based on the waveform output data, a rotation angle detected by the rotation angle detecting means after the main power supply is restored, and An absolute position detecting means for detecting the absolute position of the rotation shaft based on the rotation amount detected by the rotation amount detecting means, Sometimes, those which are configured to back up by the backup power supply at least the respective data generating means and the rotation amount detecting means (claim 1).

In this position detection device, a power interruption detection means for detecting the occurrence of power interruption, a switching means for switching the timing of the sample hold based on the detection of the occurrence of power interruption by the power interruption detection means, the first and more preferably and a common data generating means is a second data generation unit (claim 2).

The position detecting device according to claim 1 or 2 , further comprising an exciting unit that excites the resolver, wherein the exciting unit is configured to perform the pulse excitation before the occurrence of power interruption at the time of the pulse excitation. more preferably, it is configured to apply an excitation voltage amplitude is small in the resolver as compared with sinusoidal excitation (claim 3).

The present invention also provides a movable part supported so as to be reciprocally movable in a uniaxial direction, a drive mechanism for moving the movable part in the uniaxial direction using a motor as a drive source, a resolver incorporated in the motor, in uniaxial robot having a position detection device for detecting the rotational absolute positions over multiple rotations of the output shaft of the motor is a rotary shaft on the basis of the output, any one of claims 1 to 3 as the position detecting device The position detecting device according to claim 1 is provided (claim 4 ).

The present invention also provides a motor-driven robot that moves a head unit having one or more heads for picking up components, and an electronic component that is moved from the component supply unit by the head while the head unit is moved by the operation of the robot. In a surface mounter that picks up and mounts on a substrate set at a mounting work position that is a target position, a resolver incorporated into each motor of the robot, and a motor that is a rotating shaft based on the output of the resolver. A position detection device that detects a rotation absolute position over multiple rotations of the output shaft, and drive-controls the robot based on the rotation absolute position of the motor required by the position detection device to move the head unit to a desired position. and control means, further, serial to any one of claims 1 to 3 as the position detecting device In which it is provided a position detecting apparatus (claim 5).

The present invention also provides a motor-driven robot that moves a head unit having one or more heads for picking up components, and an electronic component that is moved from the component supply unit by the head while moving the head unit by the operation of the robot. In a component testing apparatus that performs various inspections by adsorbing and adhering to an inspection means that is a target position, a resolver incorporated in each motor of the robot, and an output of the motor that is a rotating shaft based on the output of the resolver A position detection device for detecting a rotational absolute position over multiple rotations of the shaft, and a control for driving and controlling the robot based on the rotational absolute position of the motor required by the position detection device to move the head unit to a desired position; and means, further, the position of any one of claims 1 to 3 as the position detecting device In which is provided with a detection device (claim 6).

Further, the present invention is based on an arm having a working head portion at the tip and supported so as to be able to turn, a motor for driving the arm to turn, a resolver incorporated in the motor, and an output of the resolver. A position detecting device that detects a rotation absolute position over multiple rotations of the output shaft of the motor that is a rotation shaft, and the position of the position of the position of the arm is determined based on the rotation absolute position. to any one of claims 1 to 3 as a detection device in which is provided with a position detecting device according to an item (claim 7).

According to the position detection device of the present invention (Claim 1), during energization, the absolute rotation position of the rotating shaft is detected based on the sine wave output from the resolver, while the first data generating means corresponds to the rotation of the rotating shaft. Waveform output data is generated. Then, when a power failure state such as a power failure occurs, waveform output data corresponding to the rotation of the rotating shaft is generated in the second data generating means based on the pulse output from the resolver, and these first and second data generating means Based on the generated output data, the rotation amount detecting means obtains the rotation amount of the rotating shaft. When the main power supply is restored, the absolute rotation position of the rotation shaft is detected based on the rotation amount obtained by the rotation amount detection means and the rotation angle detected by the rotation angle detection means after the main power supply is restored. The Rukoto. Therefore, during normal energization, the resolver is excited with a sine wave to detect the absolute rotation position of the rotary shaft based on the sine wave output, so that the absolute rotation position can be detected with high accuracy. Since the resolver is pulse-excited at the time of power interruption, power consumption at the time of power interruption can be reduced. In addition, the sampler holds the output of the resolver before and after the occurrence of power interruption to obtain continuous waveform output data corresponding to the rotation of the rotating shaft, and based on such waveform output data, Since the rotation amount of the rotation shaft is continuously detected, the rotation amount can be detected with high accuracy, and as a result, the absolute rotation position after the main power supply is restored can be detected with higher accuracy. Therefore, it is possible to improve the reliability of the absolute rotation position detected after the main power supply is restored while reducing the power consumption at the time of disconnection.

In the description of the claims, “sine wave excitation” means excitation by applying a sine wave signal having a predetermined frequency to the resolver as an excitation signal (excitation voltage), and “pulse excitation” means excitation signal ( This means that excitation is performed by applying a pulse signal having a predetermined frequency to the resolver as an excitation voltage. “Rotation angle” means an angular difference from the reference position during one rotation of the rotation shaft, and “rotation amount” means a rotation speed over multiple rotations from the coaxial reference position. The “absolute position” means a position specified up to “a rotation angle during one rotation” in addition to the “amount of rotation”. Further, “after the main power supply is restored” means that the main power supply is turned off and then returned to the energized state (or restored) .

The position detecting device this, especially according to the configuration according to claim 2, it is possible to generate the waveform output data by using a common data generating means, it is possible to rationally simplified device configuration. Specifically, when the power is turned on, the peak value of the sine wave output from the resolver is sampled and held at a fixed period, and after power interruption, the output is sampled and held at the timing of the pulse output from the resolver. The waveform output data can be generated by a common data generation means by switching the timing in synchronization with each other.

Further, according to the configuration of claim 3 , it becomes possible to further reduce the power consumption during the power interruption, and to save the backup power supply.

On the other hand, according to the single-axis robot according to the present invention (Claim 4 ), since the position detecting device as described above is provided, even when a power failure occurs, the absolute rotational position of the output shaft is determined after the main power supply is restored. It can be detected with high accuracy. Therefore, it is possible to move various members mounted on the movable portion with higher accuracy with respect to the target position. In addition, since power consumption at the time of power interruption can be reduced, a backup power source (battery) can also be saved.

Further, according to the surface mounting machine (Claim 5 ) and the component testing apparatus (Claim 6 ) according to the present invention, the position detecting device as described above is provided as the position detecting device of the output shaft of the motor that drives the robot. Therefore, even when a power failure occurs, the absolute rotation position of the output shaft can be detected with high accuracy after the main power supply is restored. Accordingly, it is possible to move the head unit with respect to the target position with higher accuracy. In addition, since power consumption at the time of power interruption can be reduced, the backup power source (battery) of the apparatus can be saved.

Further, according to the SCARA robot according to the present invention (Claim 7 ), since the position detecting device as described above is provided as the position detecting device of the output shaft of the motor for driving the arm to turn, when a power failure or the like occurs However, the absolute rotation position of the output shaft can be detected with high accuracy after the main power supply is restored. Therefore, it is possible to move the arm (head portion) more accurately with respect to the target position. In addition, since power consumption at the time of power interruption can be reduced, the backup power source (battery) of the apparatus can be saved.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 schematically shows a surface mounter (a surface mounter to which the position detection method and apparatus according to the present invention are applied) according to the present invention. As shown in the figure, on a base 1 of a surface mounter (hereinafter abbreviated as a mounter), a printed board transporting conveyor 2 is arranged, and the printed circuit board 3 is transported on the conveyor 2 to a predetermined level. It is stopped at the mounting work position.

  On both sides of the conveyor 2, component supply units 4 are arranged. These component supply units 4 are provided with multiple rows of tape feeders 4a. Each tape feeder 4a is configured such that small chip components such as ICs, transistors, capacitors, etc. are accommodated at predetermined intervals, and the held tapes are led out from the reels. As the parts are taken out, the parts are taken out intermittently.

  Above the base 1, a head unit 6 for component mounting is provided. The head unit 6 is movable across the component supply unit 4 and the component mounting unit on which the printed circuit board 3 is located, and is in the X-axis direction (direction parallel to the conveyor 2) and the Y-axis direction (direction orthogonal to the conveyor 2). Can be moved to.

  That is, a fixed rail 7 in the Y-axis direction and a ball screw shaft 8 that is rotationally driven by a Y-axis servomotor 9 are disposed on the base 1, and a head unit support member 11 is disposed on the fixed rail 7. And a nut portion 12 provided on the support member 11 is screwed onto the ball screw shaft 8. The support member 11 is provided with a guide member 13 in the X-axis direction and a ball screw shaft 14 driven by an X-axis servo motor 15, and the head unit 6 is movably held by the guide member 13. A nut portion (not shown) provided on the head unit 6 is screwed onto the ball screw shaft 14. The support member 11 is moved in the Y-axis direction by the operation of the Y-axis servo motor 9, and the head unit 6 is moved in the X-axis direction with respect to the support member 11 by the operation of the X-axis servo motor 15. ing.

  Resolvers 10 and 16 are incorporated in the Y-axis servo motor 9 and the X-axis servo motor 15, respectively, so that the position control of the head unit 6 is performed based on the outputs from the resolvers 10 and 16. It has become.

  Although not shown, the resolvers 10 and 16 include, for example, a rotor having a single-phase excitation coil fixed to the output shaft of the servo motors 9 and 15 and a two-phase output coil that is 90 ° out of phase. 1-phase excitation 2-phase output type having a stator and an induced voltage generated in the output coil by applying an excitation voltage (excitation signal) to the excitation coil, that is, an induced voltage corresponding to the rotational angle position of the output shaft Is output to the controller as a response signal.

  A plurality of mounting heads 18 for mounting components are mounted on the head unit 6. In this embodiment, six mounting heads 18 are mounted in a line at equal intervals in the X-axis direction.

  The mounting head 18 can be moved in the Z-axis direction and rotated around the R-axis (nozzle center axis) with respect to the frame of the head unit 6. It is driven by. Each mounting head 18 is provided with a suction nozzle (not shown) at its tip (lower end), and negative pressure is supplied to the tip of the suction nozzle from a negative pressure supply means (not shown). Parts are attracted by the suction force of pressure.

  On the base 1, an image pickup unit 20 for recognizing an image of the suction state of the components by the head unit 6 is further provided. The imaging unit 20 includes, for example, a camera having a CCD line sensor and an illuminating device including a large number of LEDs, and the components adsorbed to each mounting head 18 while the head unit 6 moves on the imaging unit 20. An image is taken from the lower side.

  The basic mounting operation by this mounting machine is as follows.

  When the mounting operation is started, first, the head unit 6 moves to the component supply unit 4, and the components are adsorbed by the mounting heads 18. Specifically, after the mounting head 18 is disposed above the target tape feeder 4a, the mounting head 18 moves up and down to take out the components in the tape from the tape feeder 4a while being sucked by the suction nozzle. .

  When the suction of the components is completed, the head unit 6 moves from the component supply unit 4 onto the printed circuit board 3. During this movement, the components adsorbed to each mounting head 18 are imaged as the head unit 6 passes over the imaging unit 20, and the component adsorbing state (adsorption error) by each mounting head 18 based on the image. ) Is determined, and the target position is reset based on the suction error.

  When the head unit 6 reaches the printed circuit board 3, the first component is mounted on the printed circuit board 3 as the mounting heads 18 are moved up and down, and thereafter the head unit 6 moves intermittently to the mounting position. The remaining suction parts are sequentially mounted on the printed circuit board 3.

  When all the components are mounted on the printed circuit board 3 in this way, the head unit 6 is reset on the component supply unit 4, and thereafter the head unit 6 moves back and forth between the component supply unit 4 and the printed circuit board 3. A predetermined number of components are mounted on the printed circuit board 3.

  The mounting machine as described above includes a well-known CPU that executes logical operations, a ROM that stores various programs for controlling the CPU in advance, a RAM that temporarily stores various data during operation of the apparatus, and the like. A controller is provided.

  FIG. 2 shows the configuration of a part of the controller corresponding to the main part of the present invention, that is, a part for detecting the rotational position of the servo motors 9 and 15 for driving the head unit 6 (hereinafter referred to as a position detection function part 30; FIG. 1 is a block diagram showing a configuration of a position detection device according to the present invention.

  As shown in the figure, the position detection function part 30 is backed up by a first operating unit 32 that operates only when the main power supply of the mounting machine is on (referred to as energization) and a backup power supply 66, that is, always energized. And a second operating unit 34 that operates not only when a power failure occurs but also when a power failure occurs.

  The first operation unit 32 includes a sine wave excitation circuit 40, an R / D (resolver / digital) converter 42, a waveform shaping circuit 44, and the like.

Sine wave excitation circuit 40 is for outputting a sine wave signal having a predetermined frequency as shown in FIG. 3 (a) as an excitation signal for the resolver 10 (16), when energized, the through excitation switch circuit 54 to be described later An excitation signal is given to the excitation coil of the resolver 10 (16).

  Based on the response signal output from the resolver 10 (16), the R / D converter 42 rotates the rotation angle θ of the servo motor 9 (15) (the rotation angle of the output shaft; the angular difference from the reference position during one rotation of the output shaft). ) Is output to the absolute position detection circuit 36 to be described later. When energized, the sine wave output from the resolver 10 (16) excited by the excitation signal output from the sine wave excitation circuit 40 (sinusoidal excitation) (see FIG. 3 (b)), the rotation angle θ is obtained.

A waveform shaping circuit 44 (corresponding to the waveform shaping means of the present invention) generates a timing signal for sample-holding a response signal in the sample hold circuit 60 described later, and is an excitation signal output from the sine wave excitation circuit 40. Is converted into a pulse waveform, and a pulse signal is output at a timing synchronized with a peak value (absolute value) of a specific period in the excitation signal. Specifically, as shown in FIG. 3C, the timing signal can be output with the peak value of the response signal (sine wave output) output from the resolver 10 (16) when the sine wave excitation is performed. Convert excitation signal to pulse waveform.

  On the other hand, the second operation unit 34 includes an absolute position detection circuit 36, a power failure detection circuit 50, a pulse excitation circuit 52, an excitation switching circuit 54, a timing switching circuit 56, an amplitude adjustment circuit 58, a sample hold circuit 60, a comparator 62, and a rotation. A quantity storage circuit 64 and the like are included.

  The absolute position detection circuit 36 is based on the rotation angle θ output from the R / D converter 42 and the rotation amount output from the rotation amount storage circuit 64 (the number of rotations over multiple rotations from the reference position of the output shaft). This calculates the current absolute rotation position of the output shaft (the position specified up to the rotation angle during one rotation of the output shaft in addition to the amount of rotation), and this mounting machine uses the servo absolute position based on the calculated absolute rotation position. The motors 9 and 15 are driven and controlled. In this embodiment, the R / D converter 42 constitutes the rotation angle detection means of the present invention, and the absolute position detection circuit 36 constitutes the absolute position detection means of the present invention.

  The power failure detection circuit 50 (power failure detection means) detects a power failure state such as a disconnection or a power failure and outputs a detection signal. For example, as shown in FIGS. When the voltage of the main power supply (control power supply of the controller) drops to the predetermined value Vs due to the occurrence, a detection signal is output to the pulse excitation circuit 52 and the timing switching circuit 56 at that time.

  The pulse excitation circuit 52 outputs a pulse wave as shown in FIG. 4A as an excitation signal for the resolver 10 (16). When the power is cut off, the excitation signal is transmitted via the excitation switching circuit 52 to the resolver 10 ( 16) to the exciting coil. The pulse excitation circuit 52 is configured to output a signal having a sufficiently small amplitude to the resolver 10 (16) as compared with the excitation signal output from the sine wave excitation circuit 40.

  The excitation switching circuit 54 switches an excitation signal to be applied to the resolver 10 (16). When energized, the excitation switching circuit 54 applies a sine wave excitation signal output from the sine wave excitation circuit 40 to the resolver 10 (16). That is, when a power interruption detection signal from the power interruption detection circuit 50 is input, an excitation signal of a pulse wave output from the pulse excitation circuit 52 is given to the resolver 10 (16). That is, in this embodiment, the sine wave excitation circuit 40, the pulse excitation circuit 52, and the excitation switching circuit 54 constitute the excitation means of the present invention.

  The timing switching circuit 56 (switching means) switches the sample and hold timing of the response signal in the sample and hold circuit 60, and outputs the timing signal output from the waveform shaping circuit 44 to the sample and hold circuit 60 as it is when energized. At the time of electricity, the timing synchronized with the excitation signal output from the pulse excitation circuit 52, specifically, as shown in FIG. 4C, the response signal (16) output from the resolver 10 (16) when pulse excitation is performed. A signal having a timing at which the pulse output becomes a peak value is generated and output to the sample hold circuit 60.

  The amplitude adjustment circuit 58 adjusts the amplitude of, for example, a pulse output at the time of disconnection of the response signal from the resolver 10 (16) with reference to a sine wave output at the time of energization. That is, as described above, an excitation signal having a smaller amplitude than when energized is supplied to the resolver 10 (16) at the time of disconnection, and accordingly, the amplitude of the response signal at the time of disconnection is correspondingly smaller than that at the time of energization. . The amplitude adjusting circuit 58 adjusts the amplitude so that the amplitude of the response signal at the time of power interruption is equivalent to that at the time of energization. The amplitude adjustment circuit 58 outputs the response signal from the resolver 10 (16) to the sample hold circuit 60 as it is when energized.

  The sample hold circuit 60 samples and holds the response signal (induced voltage) from the resolver 10 (16) that has passed through the amplitude adjustment circuit 58 in accordance with the timing signal from the timing switching circuit 56. More specifically, when energized, as shown in FIG. 3C, the response signal from the resolver 10 (16) is sampled and held based on the timing signal output from the waveform shaping circuit 44. As shown in FIG. 4C, the response signal is sampled and held based on the timing signal generated by the timing switching circuit 56.

  The comparator 62 binarizes the data sampled and held by the sample and hold circuit 60 (waveform output data) by setting a predetermined threshold value, and the sampled and held data is a rectangle suitable for detecting the rotation amount of the output shaft. It is converted into wave data and output.

The rotation amount storage circuit 64 calculates the rotation amount of the output shaft based on the rectangular wave data generated by the comparator 62 and outputs the result to the absolute position detection circuit 36 .

  In the present embodiment, the data generation means of the present invention (a common data generation means that also serves as the first and second data generation means) by the sample hold circuit 60 is replaced by the comparator 62 and the rotation amount storage circuit 64. These rotation amount detecting means are respectively configured.

  According to the configuration of the position detection function part 30 as described above, the detection of the absolute rotation position by the servo motors 9 and 15 is performed as follows. Hereinafter, a description will be given with reference to FIG. In FIG. 6, voltage is plotted on the vertical axis and time is plotted on the horizontal axis. (B) Excitation signal given to resolver 10 (16), (b) Response signal from resolver 10 (16), (c) Sample The response signal after the hold and (d) the rectangular wave data obtained by binarizing the response signal after the sample and hold are shown respectively, and the time point t0 is the time point when the power failure detection circuit 50 detects the occurrence of power failure. Is shown.

  First, at the time of energization (before time t0), both the first operation unit 32 and the second operation unit 34 are operated by receiving power supply from the main power source, and an excitation signal (sinusoidal wave) from the sine wave excitation circuit 40. A signal (FIG. 6A) is given to the resolver 10 (16). As a result, the resolver 10 (16) is excited with a sine wave, and a response signal (sine wave output; FIG. 6 (b)) is output to the R / D converter 42 to obtain the rotation angle θ of the output shaft.

  In parallel with this, a response signal from the resolver 10 (16) is output to the sample hold circuit 60 through the amplitude adjustment circuit 58, and sine wave data as shown in FIG. Based on the data, the comparator 62 generates rectangular wave data as shown in FIG. 6B, and the rotation amount storage circuit 64 obtains the rotation amount of the output shaft from the rectangular wave data.

  Based on the rotation angle θ of the output shaft obtained by the R / D converter 42 and the rotation amount obtained by the rotation amount storage circuit 64, the absolute position detection circuit 36 determines the servo motors 9 and 15 (output shafts). The absolute rotation position is determined.

  Thus, during energization, the servo motors 9 and 15 are driven and controlled based on the absolute rotation position obtained by the absolute position detection circuit 36 as described above.

  In such a drive control state of the servo motors 9 and 15, when a power interruption state such as a power failure occurs, the power supply from the main power supply is cut off and the first operation unit 32 of the position detection function unit 30 stops. However, the second operation unit 34 is backed up by the backup power source 66 and continuously operates.

  When a power interruption occurs (after time t0), an excitation signal (pulse signal; FIG. 6 (a)) from the pulse excitation circuit 52 is given to the resolver 10 (16) by switching the excitation switching circuit 54. As a result, the resolver 10 (16) is pulse-excited and a response signal (pulse output; FIG. 6B) is output to the amplitude adjustment circuit 58. The response signal is waveform-shaped by the amplitude adjustment circuit 58 and then output to the sample hold circuit 60 to generate waveform output data (FIG. 6C). Further, the comparator 62 generates rectangular wave data based on this data. (FIG. 6D) is generated, and the rotation amount of the output shaft is obtained in the rotation amount storage circuit 64 from this rectangular wave data.

  When the main power supply returns, the absolute position detection circuit 36 uses the servo motor 9 based on the rotation amount obtained by the rotation amount storage circuit 64 and the rotation angle θ of the output shaft obtained by the R / D converter 42 after the main power supply is restored. , 15 (output shaft) is obtained.

  According to the mounting machine as described above, regarding the position detection of the servo motors 9 and 15 for driving the head unit 6, during normal energization, the resolver is excited with a sine wave and the servo motors 9, Since the rotation absolute position of 15 (output shaft) is detected, the rotation absolute position can be detected with high accuracy. In addition, by continuously sample-holding the response signal from the resolver 10 (16) before and after the occurrence of power interruption (time t0 in FIG. 6), it corresponds to the rotation of the output shaft as shown in FIG. 6 (c). Since the waveform output data having continuity is acquired, and the waveform output data is binarized by the comparator 62 to detect the rotation amount, the rotation amount of the output shaft is continuously detected. The absolute rotation position after return can be detected more accurately. That is, it is possible to accurately detect the rotation amount without any error by detecting the rotation amount of the output shaft without interruption before and after the occurrence of power interruption. Therefore, for example, as in Patent Document 1 described in the related art, the rotation detected when compared with the method of correcting the rotation amount stored at the time of power interruption based on the response signal (pulse output) from the resolver after power interruption. The quantity accuracy is high. Accordingly, the absolute rotation position of the servo motors 9 and 15 after the main power supply is restored can be detected with higher accuracy.

  In addition, when the power is cut off, the resolver 10 (16) is pulse-excited to detect the absolute rotation position based on the pulse output, so that the power consumption at the time of the power cut (consumption of the backup power supply 66) can be reduced. it can.

  Therefore, according to the mounting machine described above, it is possible to more accurately control the position of the head unit 6 after the main power supply is restored (restarted) while reducing the power consumption at the time of power interruption.

  Although not described in detail in the above embodiment, in the surface mounter shown in FIGS. 1 and 2, the head unit support member 11 includes the X-axis direction guide member 13 and the X-axis servomotor 15 as described above. A ball screw shaft 14 to be driven is disposed, the head unit 6 is movably held by the guide member 13, and a nut portion provided in the head unit 6 is screwed to the ball screw shaft 14, so that X The head unit 6 is moved in the X-axis direction with respect to the support member 11 by the operation of the axis servo motor 15. Therefore, in the above embodiment, the single-axis robot of the present invention is also constituted by these support members 11 and the like. Will be. That is, the movable unit of the single-axis robot is driven by the head unit 6, the drive mechanism is driven by the support member 11, the guide member 13, the ball screw shaft 14, and the X-axis servomotor 15, and the position detection function portion 30 of the controller is used for the position of the present invention. Each detection device is configured.

  By the way, the mounting machine described above is one form of the surface mounting machine according to the present invention (the surface mounting machine to which the position detection method and apparatus according to the present invention is applied), and its specific configuration and position detection. The specific configuration of the method and the apparatus can be changed as appropriate without departing from the scope of the present invention.

  For example, in the embodiment, the sample hold circuit 60, the comparator 62, and the rotation amount storage circuit 64 are provided only in the second operation unit 34 in the position detection function part 30 of the controller, and the timing of the sample hold is switched by the timing switching circuit 56. Is configured to detect the amount of rotation of the output shaft using a common circuit 60 or the like when energized or disconnected, but of course, an independent sample hold circuit or the like is provided in the first operating unit 32, The rotation amount of the output shaft during energization may be detected by a sample hold circuit or the like provided in the first operation unit 32 (in this case, the present invention is provided by the sample hold circuit of the first operation unit 32). The first data generation means is configured, and the second data generation means of the present invention is configured by the sample hold circuit 60 of the second operation unit 34. That). That is, you may comprise so that the rotation amount of the output shaft at the time of electricity supply and the rotation amount of the output shaft at the time of a power disconnection may be detected by a separate independent circuit. However, according to the configuration in which the sample hold circuit 60 and the like of the second operation unit 34 are shared as in the embodiment, there is an advantage that the configuration of the controller (position detection function portion 30) can be rationally simplified. is there.

  In the controller (position detection function part 30) of the embodiment, the pulse excitation circuit 52 applies an excitation signal having a smaller amplitude (voltage) than the excitation signal output from the sine wave excitation circuit 40 to the resolver 10 (16). However, of course, it may be a signal having an amplitude equal to or greater than the excitation signal output from the sine wave excitation circuit 40. However, according to the configuration of the embodiment, it is possible to reduce the power consumption during power interruption, and thus there is an advantage that the backup power supply 66 can be further saved.

  In addition, the power interruption detection circuit 50 of the embodiment is configured to output a detection signal at that time when the voltage of the main power supply drops to the predetermined value Vs (see FIGS. 5A and 5B). For example, as shown in FIGS. 7A and 7B, the amplitude (voltage) of the excitation signal output from the sine wave excitation circuit 40 is a predetermined value VDs. A power interruption may be detected when a certain time (t) elapses after descending. Alternatively, in order to increase the reliability of detection of power interruption, both of the detection methods shown in FIGS. 5 and 7 are adopted, and the time when the voltage of the main power source reaches the predetermined value Vs or the above-described fixed time (t) elapses. The detection signal may be output at a later point in time.

  Moreover, in the controller (position detection function part 30) of the embodiment, the absolute position detection circuit 36 is provided in the second operating part 34, but may be provided in the first operating part 32, for example. In this case, the R / D converter and the absolute position detection circuit 36 can be integrally configured by a CPU.

  In the above embodiment, the present invention is applied to a surface mounter. However, for example, the present invention can also be applied to a component testing apparatus that inspects an electronic component such as an IC chip.

  FIG. 8 is a plan view showing a component test apparatus according to the present invention (a component test apparatus to which the position detection method / apparatus according to the present invention is applied).

  As shown in FIG. 8, the base 71 of the component testing apparatus 70 is provided with a cassette installation portion 73 on which cassettes 72 in which wafers Wa in which bare chips are diced are stored in multiple stages can be mounted. The cassette 72 attached to the cassette installation unit 73 is transported to a position below the opening 74 formed in the base 71 by a transport mechanism (not shown), and the bare chip is picked up by the head 75 at this position. The head 75 conveys the bare chip from the opening 74 to the component standby unit 77 along a rail 76 extending in the Y-axis direction on the base 71.

  The component standby unit 77 is disposed between a pair of rails 78 extending in the X-axis direction on the base 71, and a pair of bare chips conveyed to the component standby unit 77 are driven along each rail 78. The head units 79 and 80 are transported to the inspection socket 81 on the base 71, and a predetermined inspection is performed. In the head unit 79 (80), two inspection heads 79a (81a) capable of attracting bare chips are provided side by side.

  The bare chip determined to be defective as a result of the inspection in the inspection socket 81 is conveyed to the defective product tray 89 of the defective product recovery unit 88 by the head units 79 and 80, and is determined to be good. The bare chip is conveyed to the component storage section 90 on the base 71 by the head units 79 and 80, and is stored in the base tape 91 for the tape feeder in the component storage section 90. A cover tape (not shown) is attached to the cover.

  When the defective product tray 89 of the defective product collection unit 88 is fully loaded, the tray 89 is transferred to the tray discharge unit 92 by a tray moving mechanism (not shown) and the tray standby adjacent to the defective product collection unit 88 is waited for. The tray 94 in the section 93 is transferred to the defective product collection section 88 by the head units 79 and 80, and the empty tray is transferred from the empty tray mounting section 85 to the tray standby section 83 by a tray moving mechanism (not shown). It has become.

  In such a component testing apparatus, the head 75 and the head units 79 and 80 are configured to move along the rails 76 and 78 by a ball screw mechanism using a motor as a drive source, respectively, and are incorporated in the motor. The position of the head 75 and head units 79 and 80 is controlled by detecting the absolute rotation position of the motor based on the response signal from the resolver. The controller that controls the component testing apparatus is provided with a position detection function part (see FIG. 2) similar to the surface mounter of the above embodiment as a part for detecting the position of the motor. The function part detects the absolute rotation position of the motor that drives the head 75 and the head units 79 and 80, respectively.

  According to such a component testing apparatus, regarding the detection of the absolute rotation position of the motor that drives the head 75 and the head units 79 and 80, the reliability of the detection value (rotational absolute position) while reducing the power consumption at the time of power interruption. Therefore, the position control of the head 75 and the like, in particular, the position control of the head 75 and the like after restarting after the occurrence of power failure can be performed with higher accuracy.

  In the above embodiment, the present invention is applied to a surface mounter. However, for example, the present invention can also be applied to a so-called single-axis robot.

  FIG. 9 schematically shows a cross-sectional view of a single-axis robot according to the present invention (a single-axis robot to which the position detection method and apparatus according to the present invention are applied).

  As shown in this figure, a single-axis robot 101 has an elongated casing in a uniaxial direction composed of a base 102, a cover 103, and the like, and a movable member 104 is movably provided in the casing and provided in the casing. The movable member 104 is driven by the drive mechanism 105 provided.

  The driving mechanism 105 includes a guide rail 110 fixed on the base 102 and extending in one axial direction, a ball screw shaft 111 extending in parallel with the guide rail 110 and rotatably supported by the base 102, and the ball screw. And a motor 112 for rotating the shaft 111. The movable member 104 is movably mounted on the guide rail 110, and a nut member 104a integrally incorporated in the movable member 104 includes the ball screw shaft. 111 is screwed. Then, when the ball screw shaft 111 that is the rotation shaft is driven to rotate in the forward and reverse directions by the motor 112 that is the drive source, the movable member 104 is moved along the guide rail 110 in a uniaxial direction accordingly. Yes. The movable member 104 is provided with a mounting portion 104b exposed to the outside from the slit 103a formed in the casing, and various working members are mounted on the mounting portion 104b.

  In the drive mechanism 105, the ball screw shaft 111 is rotatably supported via bearings 116 and 117 on support bases 114 and 115 having both front and rear end portions (right and left end portions) fixed to the base 102, as shown in FIG. ing. The rear end of the ball screw shaft 111 extends further rearward than the support base 115, and the motor 112 is assembled to the extended portion 111a.

  The motor 112 has a motor main body 122 and a resolver 124. The motor main body 122 includes a stator 122a and a rotor 122b, and the rotor 122b is integrally coupled to the extended portion 111a of the ball screw shaft 111 through a key 118 in a state in which relative rotation is impossible. On the other hand, the stator 122a is disposed outside the rotor so as to face the rotor 122b and is fixed to the frame member 120 of the motor 112. The frame member 120 is fixed to the base 102 and is configured to form the casing in cooperation with the cover 103 and the like, and has a hollow portion that opens toward the front side of the ball screw shaft 111. The stator 122a is fixed to the inner wall portion of the hollow portion. A bearing 126 is disposed at the back end (the left end in the figure) of the frame member 120, and the end of the ball screw shaft 111 (the end of the extended portion 11 a) supports the bearing 126. Via the frame member 120 so as to be rotatable.

  The resolver 124 is, for example, a one-phase excitation two-phase output type similar to that of the above-described embodiment, and includes a rotor 124b including a one-phase excitation coil fixed to the extended portion 111a of the ball screw shaft 111. , And a stator 124a having two-phase output coils that are 90 ° out of phase. Then, when an excitation voltage (excitation signal) is applied to the excitation coil, an induced voltage generated in the output coil, that is, an induced voltage corresponding to the rotation angle position of the output shaft is output as a response signal.

  The controller of the motor 122 is provided with a position detection function part (see FIG. 3) similar to the surface mounter of the above-described embodiment as a part for detecting the rotational position of the motor. The absolute rotation position of the motor 122 is detected.

  According to such a single-axis robot, regarding the detection of the absolute rotation position of the motor that drives the movable member 104, the reliability of the detection value (rotational absolute position) can be improved while reducing the power consumption at the time of disconnection, Therefore, the position control of the working member attached to the movable member 104, particularly the position control of the head 75 and the like after the main power supply is restored (restarted) after the occurrence of a power failure such as a power failure can be performed with higher accuracy. It becomes possible.

  Furthermore, the present invention can also be applied to a so-called SCARA robot.

  FIG. 10 schematically shows a SCARA robot according to the present invention (a SCARA robot to which the position detection method / apparatus according to the present invention is applied).

  The SCARA robot shown in this figure includes a hollow base 201 formed in a cylindrical shape, a horizontal joint-type arm 202, and a working head portion 203 provided at the tip of the arm 202. ing. The arm 202 includes a first arm 202a and a second arm 202b in the illustrated example, and the base end portion of the first arm 202a is attached to the base 201 via a first shaft 204 which is a vertical rotation shaft. The base end of the second arm 202b is rotatably connected to the distal end of the first arm 202a via a second shaft 205 that is a vertical rotation shaft. . Further, a vertical operation shaft 206 is provided at the tip of the second arm 202b so as to be able to move up and down, and the head portion 203 is provided at the lower end of the operation shaft 206. The member can be attached.

  A first shaft motor 210 is installed in the base 201, and the first arm 202a is turned by rotating the first shaft 204 by the motor 210. A housing 207 is provided on the second arm 202b, and a second shaft motor, a Z-axis motor, and an R-axis motor (not shown) are disposed in the housing 207, and the second shaft 205 is moved by the second shaft motor. By being driven, the second arm 202b rotates with respect to the first arm 202a, and the operating shaft 206 is moved up and down by driving the Z-axis motor and the R-axis motor.

  A small chamber 208 for wiring and piping is connected to the side of the base 201, and a flexible pipe between the small chamber 208 and the housing 207 through which piping such as electric wiring and air is passed. 209 is connected.

The first shaft motor 210 disposed inside the base 201 has a motor main body portion 211 disposed such that the output shaft that is a rotation shaft faces upward, and a resolver 212 assembled to the lower end portion thereof. The output shaft of the motor main body 211 is connected to the first shaft 204 via a speed reducer 213. The resolver 212 is, for example, a one-phase excitation two-phase output type similar to that of the above-described embodiment. Although not shown, the rotor includes a one-phase excitation coil fixed to the output of the motor main body. And a stator that is fixed to the body of the motor main body part. Then, when an excitation voltage (excitation signal) is applied to the excitation coil, an induced voltage generated in the output coil, that is, an induced voltage corresponding to the rotation angle position of the output shaft is output as a response signal.

Similarly to the first axis motor 210, the second axis motor mounted on the second arm 202b also has a motor main body portion and a resolver, and the output shaft of the motor main body portion is connected to the second axis via a speed reducer. 205 is connected.

  The controller for the single-axis motor 210 and the second-axis motor is provided with a position detection function portion (see FIG. 3) similar to the surface mounter of the above-described embodiment as a portion for detecting the rotational position of each motor. The position detection function unit detects the absolute rotation position of the motor 210.

  According to such a SCARA robot, it is possible to improve the reliability of the detection value (rotation absolute position) while reducing the power consumption at the time of disconnection regarding the detection of the rotation absolute position of the motor 210 or the like that drives the arm 202. Therefore, it is possible to perform the position control of the working member attached to the head portion 203, in particular, the position control after the main power supply is restored (restarted) after the occurrence of power failure such as a power failure. Become.

1 is a plan view showing a surface mounter according to the present invention (a surface mounter to which the position detection method / apparatus according to the present invention is applied). It is a block diagram which shows the part (position detection function part) which performs the position detection of the servomotor for driving a head unit among the functional structures contained in the controller of a surface mounter. FIG. 6 is a diagram showing various signals for detecting the absolute rotation position of the servo motor (when power is supplied from the main power supply (when energized)), (a) is an excitation signal given to the resolver, and (b) is A response signal from the resolver, (c) shows a timing signal for sampling and holding the response signal from the resolver, and (d) shows a waveform data signal generated by sampling and holding the response signal from the resolver. . FIG. 6 is a diagram showing various signals for detecting the absolute rotation position of the servo motor (a state where power supply from the main power supply is cut off (when power is cut off)), (a) is an excitation signal given to the resolver, and (b). Is a response signal from the resolver, (c) is a timing signal for sampling and holding the response signal from the resolver, and (d) is a waveform data signal generated by sampling and holding the response signal from the resolver. Yes. It is a figure explaining the generation | occurrence | production detection method of the disconnection by a disconnection detection circuit. It is a diagram showing various signals for detecting the absolute rotation position of the servo motor. (A) is the excitation signal given to the resolver, (b) is the response signal from the resolver, (c) By sampling and holding the response signal The generated waveform data signal (2) indicates rectangular wave data obtained by binarizing the waveform data (c). It is a figure explaining the generation | occurrence | production detection method of the disconnection by a disconnection detection circuit. 1 is a plan view showing a component testing apparatus according to the present invention (a position detection method according to the present invention and a component testing apparatus to which the apparatus is applied). 1 is a plan view showing a single-axis robot (single-axis robot to which the position detection method and apparatus according to the present invention are applied) according to the present invention. 1 is a plan view showing a SCARA robot according to the present invention (a SCARA robot to which the position detection method / apparatus according to the present invention is applied).

9, 15 Servo motors 10, 16 Resolver 30 Position detection function part 32 1st operation part 34 2nd operation part 36 Absolute position detection circuit 42 R / D converter 40 Sine wave excitation circuit 44 Waveform shaping circuit 50 Disconnection detection circuit 54 Excitation Switching circuit 56 Timing switching circuit 58 Amplitude adjustment circuit 60 Sample hold circuit 62 Comparator 64 Rotation amount memory circuit

Claims (7)

When the resolver of the rotating shaft to which the resolver is assembled is excited with a sine wave, the absolute position of the rotating shaft over multiple rotations is detected based on the output of the sine wave, and the main power is cut off. When power is supplied, the resolver is pulse-excited using a backup power supply to detect the rotation amount of the rotating shaft based on the pulse output that is the output, and after the main power supply is restored, based on the rotation amount and the sine wave output A device for detecting the absolute position of rotation based on the rotation angle of the rotation shaft detected in
Rotation angle detecting means for detecting a rotation angle of the rotation shaft based on the sine wave output;
Using a sine wave excitation signal for exciting the resolver, by converting this signal, waveform shaping means for outputting a timing signal when the absolute value of the sine wave output from the resolver peaks,
First data generating means for generating waveform output data corresponding to the rotation of the rotating shaft by sampling and holding the sine wave output from the resolver in synchronization with the timing signal ;
A second data generating means for generating waveform output data corresponding to the rotation of the rotating shaft by sample-holding the pulse output from the resolver after the occurrence of power interruption ;
A rotation amount detection means for continuously detecting the rotation amount of the rotation shaft before and after the occurrence of power interruption based on the waveform output data generated by the first and second data generation means ;
And a absolute position detecting means for detecting the rotational absolute positions of the rotating shaft on the basis of the rotation amount detected by the rotation amount detection means and the rotation angle detected by the rotation angle detecting means after return of the main power supply ,
A position detection apparatus configured to back up at least each of the data generation means and the rotation amount detection means with the backup power supply when a power interruption occurs . The position detection device according to claim 1,
A power interruption detection means for detecting the occurrence of the power interruption;
Switching means for switching the timing of the sample hold based on detection of occurrence of power interruption by the power interruption detection means;
A common data generation means as the first and second data generation means;
Position detecting device characterized in that it comprises a. In the position detection device according to claim 1 or 2,
Excitation means for exciting the resolver, and this excitation means applies an excitation voltage having a smaller amplitude than the sine wave excitation before the occurrence of power interruption to the resolver during the pulse excitation after the occurrence of power interruption. position detecting apparatus according to claim to Rukoto. A movable part supported so as to be reciprocally movable in one axial direction, a drive mechanism for moving the movable part in the one axial direction using a motor as a drive source, a resolver incorporated in the motor, and a rotating shaft based on the output of the resolver A single-axis robot provided with a position detection device that detects an absolute rotation position over multiple rotations of the output shaft of the motor,
Uniaxial robot characterized that you have provided a position detecting apparatus according to any one of claims 1 to 3 as the position detecting device. A motor-driven robot that moves a head unit that includes one or more heads for picking up components, and a target position that picks up electronic components from a component supply unit by the head while moving the head unit by operating the robot. In a surface mounter that mounts on a substrate set at a mounting work position,
A resolver incorporated into each motor of the robot;
A position detection device that detects an absolute rotation position over multiple rotations of the output shaft of the motor, which is a rotation shaft, based on the output of the resolver;
Control means for driving and controlling the robot based on the absolute rotation position of the motor required by the position detection device to move the head unit to a desired position;
Surface mounter which is characterized in that it comprises a position detecting device according to any one of claims 1 to 3 as the position detecting device. A motor-driven robot that moves a head unit that includes one or more heads for picking up components, and a target position that picks up electronic components from a component supply unit by the head while moving the head unit by operating the robot. In a component testing apparatus that performs various inspections by transferring to an inspection means,
A resolver incorporated into each motor of the robot;
A position detection device that detects an absolute rotation position over multiple rotations of the output shaft of the motor, which is a rotation shaft, based on the output of the resolver;
Control means for driving and controlling the robot based on the absolute rotation position of the motor required by the position detection device to move the head unit to a desired position;
Device test apparatus characterized by comprising a position detecting device according to any one of claims 1 to 3 as the position detecting device. An arm having a working head portion at the tip and supported so as to be able to turn, a motor for driving the arm to rotate, a resolver incorporated in the motor, and the motor that is a rotating shaft based on the output of the resolver A position detecting device that detects a rotational absolute position over multiple rotations of the output shaft, and a SCARA robot that detects the turning position of the arm based on the absolute rotational position.
SCARA robots, characterized in that it comprises a position detecting device according to any one of claims 1 to 3 as the position detecting device.