JP4360257B2 - Electronic component mounting apparatus and state determination method in electronic component mounting apparatus - Google Patents

Description

  The present invention relates to an electronic component mounting apparatus used in an electronic component mounting line for mounting an electronic component on a substrate, and a state determination method in the electronic component mounting apparatus.

  The electronic component mounting line is configured by connecting a plurality of electronic component mounting devices such as a screen printing device and an electronic component mounting device. These devices perform predetermined work operations by moving work heads such as squeegee heads for screen printing and mounting heads for transferring and mounting electronic components on a substrate by a head moving mechanism using a motor as a drive source. Execute.

The head moving mechanism is composed of a combination of mechanism elements such as ball screws and linear guides. In order to ensure smooth operation over a long period of time with such mechanism elements, the lubrication state of each part of the mechanism and the machine It is indispensable to maintain a good apparatus state such as adjustment accuracy. If operation continues for a long period of time, such as poor lubrication, poor machine adjustment, or foreign object biting, the system may shift to a state where it cannot be repaired due to wear of parts due to abnormal sliding. Large-scale repairs that involve complicated parts replacement. In order to prevent the occurrence of such a situation in advance, a method for detecting an abnormality such as damage to the mechanism has been proposed (see, for example, Patent Document 1).
JP 2001-58342 A

  However, in the above-described prior art examples, the state cannot be determined until the abnormal state occurs as a specific symptom such as an abnormal rise in temperature or the occurrence of a flaw on the ball. It was difficult to prevent situations such as damage.

  Accordingly, an object of the present invention is to provide an electronic component mounting apparatus that can detect the sign of an abnormal state and reduce the occurrence of component damage.

An electronic component mounting apparatus according to the present invention is an electronic component mounting apparatus used in an electronic component mounting line for mounting an electronic component on a board, and includes a work head that moves in at least one direction and performs a predetermined work operation; A head moving mechanism that is driven by a motor to move the working head; a control unit that controls the motor to cause the head moving mechanism to execute a predetermined state determination operation; and a torque detection unit that detects a load torque of the motor. And a state determination unit that determines whether or not the head moving mechanism is in an abnormal state based on a torque detection result by the torque detection unit when the state determination operation is performed. where the said when the load torque of the motor exceeds a determination threshold value, and said even if not exceeding the judgment threshold the head moving mechanism If the variation range in the load torque of the motor in the subject distance range exceeds the allowable variation threshold, it is determined that the abnormal state present over a certain range not normal.

The state determination method in the electronic component mounting apparatus according to the present invention is used in an electronic component mounting line for mounting an electronic component on a board, and is driven by a motor, which is driven by a motor, which moves in at least one direction and performs a predetermined work operation. An electronic device comprising: a head moving mechanism that moves a work head; a control unit that controls the motor to cause the head moving mechanism to execute a predetermined state determination operation; and a torque detection unit that detects a load torque of the motor. In the component mounting apparatus, a state determination method in the electronic component mounting apparatus that determines whether or not the head moving mechanism is in an abnormal state, wherein the torque detection unit performs the state determination operation. includes a step of determining whether the or head moving mechanism is in an abnormal state based on the torque detection result, the load bets of the motor If the click exceeds a determination threshold, and the predetermined target distance variation range variation tolerance threshold of the load torque of the motor within the scope of the even if not exceeding the judgment threshold the head moving mechanism if greater than the value, it is determined that the abnormal state present over a certain range not normal.

According to the present invention, the abnormal state of the head moving mechanism based on the torque detection result by the torque detecting means for detecting the load torque of the motor that drives the head moving mechanism and the torque detecting means when the state determination operation is executed. State determining means for determining the presence or absence of the motor, and the state determining means determines that the state is abnormal if the fluctuation range of the motor load torque within a predetermined target distance range of the head moving mechanism exceeds a fluctuation allowable threshold. Accordingly, it is possible to detect signs of some abnormal state and reduce the occurrence of component damage.

  Next, embodiments of the present invention will be described with reference to the drawings. 1 is a plan view of an electronic component mounting apparatus according to an embodiment of the present invention, FIGS. 2 and 3 are sectional views of the electronic component mounting apparatus according to an embodiment of the present invention, and FIG. 4 is an embodiment of the present invention. The block diagram which shows the structure of the control system of the electronic component mounting apparatus of form, FIG. 5 is the graph which shows the torque measurement result in the electronic component mounting apparatus of one embodiment of this invention, FIG. 6 is one embodiment of this invention It is a flowchart of the state determination in an electronic component mounting apparatus.

  First, the structure of an electronic component mounting apparatus as an electronic component mounting apparatus used in an electronic component mounting line for mounting electronic components on a substrate will be described with reference to FIGS. In FIG. 1, a transport path 2 is disposed on a base 1 in the X direction. The transport path 2 transports the substrate 3 on which electronic components are mounted, and positions the substrate 3 at a mounting position set on the transport path 2. Component supply units 4 are provided on both sides of the conveyance path 2, and a plurality of tape feeders 5 are mounted on the component supply unit 4.

Y-axis frames 6a are provided in the Y direction at both ends of the base 1 in the X direction, and guide rails 6 are disposed on the upper surface of the Y-axis frame 6a. As shown in FIGS. 2 and 3B, a slider 7 is fitted on the guide rail 6 so as to be slidable in the Y direction. The slider 7 has table end portions 8a provided at both ends of the X-axis table 8. , 8b is fixed to the lower surface. Nut 11 screw 9 sends to the lower surface of the table end 8a is screwed is coupled, as shown in FIG. 1, FIG. 3 (a), the feed screw 9 is driven to rotate by the Y-axis motor 10. By rotating and driving the Y-axis motor 10, the table end 8a is driven in the Y direction, whereby the X-axis table 8 moves in the Y direction.

  A feed screw 16 is disposed between the table end portions 8a and 8b, and the feed screw 16 is rotationally driven by an X-axis motor 17 disposed at the table end portion 8a. The feed screw 16 is screwed into a nut 18, and the nut 18 is coupled to the mounting head 12 slidable in the X direction along the X axis table 8. A slide guide mechanism for guiding the mounting head 12 is not shown. By driving the X-axis motor 17, the mounting head 12 moves in the X direction.

  As shown in FIG. 2, the mounting head 12 is a multi-type head including a plurality of unit mounting heads 12a, and the unit mounting head 12a includes a nozzle 13 at the lower end. The nozzle 13 is rotated around the nozzle axis by a θ-axis motor 14 provided in common. The mounting head 12 includes a camera 15 that moves integrally. When the mounting head 12 moves onto the substrate 3, the camera 15 is positioned on the substrate 3, and the substrate 3 is imaged to recognize the position.

  By driving the Y-axis motor 10 and the X-axis motor 17, the mounting head 12 moves in the XY direction, whereby an electronic component is picked up from the tape feeder 5 of the component supply unit 4 by the nozzle 13 of each unit mounting head 12 a. Then, the mounting operation of transferring and mounting on the substrate 3 positioned in the transport path 2 is performed. That is, the mounting head 12 is a work head that moves in at least one direction and performs a predetermined work operation. The mounting head 12 includes a guide rail 6, a slider 7, a feed screw 9, a Y-axis mechanism including a nut 11, a nut 18, and a feed screw 16. The X-axis mechanism including the X-direction slide guide mechanism constitutes a head moving mechanism that is driven by a motor and moves the aforementioned working head.

  A component recognition camera 20 and a tool stocker 21 are disposed between the conveyance path 2 and the component supply unit 4. When the mounting head 12 that has picked up the electronic component from the tape feeder 5 by the nozzle 13 moves above the component recognition camera 20, the component recognition camera 20 images the electronic component held by the nozzle 13 and thereby electronically The position of the part is recognized. The tool stocker 21 stores and holds nozzles 13 corresponding to a plurality of types of electronic components. When the mounting head 12 accesses the tool stocker 21, the nozzles 13 are replaced as necessary.

  Next, the configuration of the control system will be described with reference to FIG. The control unit 30 is a CPU and controls the operation of each part of the mounting apparatus, and controls each part described below to perform an automatic greasing operation to be described later. The motor drive unit 31 drives the Y-axis motor 10 and the X-axis motor 17. When the control unit 30 controls the Y-axis motor 10 and the X-axis motor 17 via the motor driving unit 31, the head moving mechanism executes a state determination operation described later. Therefore, the control unit 30 is a control unit that controls the motor to cause the head moving mechanism to execute a predetermined state determination operation.

  The torque measuring unit 32 is a torque detecting unit that detects the load torque of the motor, and the current value of the electric power supplied from the motor driving unit 31 to each motor as the load torque when driving the Y-axis motor 10 and the X-axis motor 17. Measure based on Based on the torque measurement result by the torque measurement unit 32 when the head moving mechanism executes the state determination operation, the state determination unit 33 is in an abnormal state in the load mechanism unit driven by these motors, that is, the sliding unit is abnormal. It is determined whether or not there is a sign of transition to a state where normal operation of the load mechanism such as wear is inhibited. That is, the state determination unit 33 is a state determination unit that determines whether or not the head moving mechanism that is the load mechanism unit is in an abnormal state based on a torque detection result by the torque detection unit when the state determination operation is executed. It has become.

  The display unit 34 is a screen display unit such as a display panel, and displays a torque measurement result (see FIG. 5) acquired by the torque measurement unit 32, a determination result by the state determination unit 33, and the like. The operation input unit 35 is an input unit such as a keyboard or a touch panel, and performs operation input for setting a state determination operation pattern and a determination threshold value, which will be described later.

  Next, with reference to FIG. 5, the state determination of the load mechanism unit and the state determination operation will be described. The graph of FIG. 5 shows that the motor (in this case, the Y-axis motor 10 or the X-axis motor 17) that drives the load mechanism is rotated at a low speed of about 50 to 100 rpm with little fluctuation in torque value due to the influence of the amount of grease. The torque measurement value when the head movement mechanism is caused to execute a predetermined state determination operation is shown with the movement stroke taken on the horizontal axis. Here, as the pattern of the state determination operation, a forward / reverse inversion operation in a low-speed rotation region is used here.

  FIG. 5A shows the torque measurement result when the load mechanism is in a normal state. When the motor is driven in this state to cause the load mechanism unit to execute the state determination operation, torque values (+) (−) corresponding to the rotation direction are recorded during forward rotation and reverse rotation, respectively. At this time, although the torque value shows some increase / decrease, as a whole, it almost converges to the torque level defined by the sliding resistance of the load mechanism at that time.

  Determination threshold values + Tth and -Tth are set by adding a margin value considered to be an allowable range to the torque level. That is, the condition for determining that the device state of the load mechanism portion of the motor is normal that the torque measurement result is within the range of the determination threshold value + Tth to −Tth and does not show a large fluctuation. It becomes.

FIG. 5B shows a measurement result 1 when it is determined that the device state of the load mechanism unit is abnormal.
The pattern is shown. In this example, a torque measurement waveform (see peak waveform indicated by an arrow) exceeding a determination threshold value + Tth is obtained at a specific position at the time of forward rotation. This indicates that there is an abnormal state that locally increases the load resistance, such as a surface flaw.

  During reverse rotation, the entire torque measurement waveform is within the range of the determination threshold value −Tth, but the torque value fluctuation range R within the predetermined target distance range L is the fluctuation allowable threshold value Rth. This indicates that the abnormal state such as a galling of the guide rail exists over a certain range. That is, if a measurement result as illustrated in FIG. 5B is obtained by torque measurement, the state determination unit 33 determines that the state is abnormal and displays that fact on the display unit 34.

  Next, a state determination method for determining whether or not the head moving mechanism is in an abnormal state in the electronic component mounting apparatus will be described with reference to the flow of FIG. Here, the shaft breakage diagnosis of the X-axis mechanism and the Y-axis mechanism of the head moving mechanism is performed. First, in FIG. 6, the shaft breakage diagnosis start is instructed by the control unit 30 (ST1), whereby a predetermined state determination operation is executed.

  That is, first, the motor is rotated in the positive direction at a low rotational speed (ST2), and the torque value is measured by the torque measuring unit 32 (ST3). Next, the rotational direction of the motor is switched, the shaft is rotated in the reverse direction at a predetermined low rotational speed (ST4), and the torque value is measured by the torque measuring unit 32 (ST5). As a result, a torque measurement result for determination as shown in FIG. 5 is acquired, and based on this measurement result, the state determination unit 33 determines the state of the head moving mechanism that is the load mechanism unit of the motor (in this case, damage determination). (ST6).

  That is, in this state determination, it is determined whether or not the head moving mechanism is in an abnormal state based on a torque detection result by the torque detecting means when the head moving mechanism is caused to execute a predetermined state determining operation. I have to. In the state determination, if it is determined that any abnormal state exists in the head moving mechanism, the operation of the apparatus is stopped, the abnormal part is searched and the cause is investigated, and necessary maintenance work is performed. Thus, in the process of continuing the operation of the electronic component mounting apparatus, by performing the above-described state determination at a predetermined timing, signs of abnormal conditions are detected before specific symptoms of abnormal operation occur. Thus, occurrence of component damage can be reduced.

  In the present embodiment, an example of an electronic component mounting apparatus that mounts an electronic component on a substrate is shown as an electronic component mounting apparatus. However, other types of electronic component mounting apparatuses that constitute an electronic component mounting line such as a screen printing apparatus. Also, the present invention can be applied.

  The electronic component mounting apparatus of the present invention has an effect of detecting signs of abnormal conditions and reducing the occurrence of component damage, and an electronic component mounting line for mounting an electronic component such as an electronic component mounting device on a substrate. It is useful for an electronic component mounting apparatus used in the above.

The top view of the electronic component mounting apparatus of one embodiment of this invention Sectional drawing of the electronic component mounting apparatus of one embodiment of this invention Sectional drawing of the electronic component mounting apparatus of one embodiment of this invention The block diagram which shows the structure of the control system of the electronic component mounting apparatus of one embodiment of this invention The graph which shows the torque measurement result in the electronic component mounting apparatus of one embodiment of this invention Flow chart of state determination in electronic component mounting apparatus of one embodiment of the present invention

Explanation of symbols

6 Guide rail 7 Slider 8 X-axis table 9 Feed screw 10 Y-axis motor 11 Nut 12 Mounting head 16 Feed screw 17 X-axis motor 18 Nut

Claims (2)

An electronic component mounting apparatus used in an electronic component mounting line for mounting an electronic component on a substrate, wherein the working head moves in at least one direction and performs a predetermined working operation, and is driven by a motor to move the working head. A head moving mechanism, control means for controlling the motor to cause the head moving mechanism to execute a predetermined state determining operation, torque detecting means for detecting a load torque of the motor, and the state determining operation. State determining means for determining whether or not the head moving mechanism is in an abnormal state based on a torque detection result by the torque detecting means at the time,
The state determination unit is configured to load the motor within a predetermined target distance range of the head moving mechanism even when the load torque of the motor exceeds a determination threshold and when the motor does not exceed the determination threshold. An electronic component mounting apparatus , wherein if the torque fluctuation range exceeds a fluctuation allowable threshold, it is determined that the abnormal state exists over a certain range. Used in an electronic component mounting line for mounting electronic components on a board, a work head that moves in at least one direction and performs a predetermined work operation, a head moving mechanism that is driven by a motor to move the work head, and controls the motor Then, in the electronic component mounting apparatus comprising: a control unit that causes the head moving mechanism to execute a predetermined state determination operation; and a torque detection unit that detects a load torque of the motor, the head moving mechanism is in an abnormal state. A state determination method in the electronic component mounting apparatus for determining whether the head movement mechanism is in an abnormal state based on a torque detection result by the torque detection unit when the state determination operation is executed. Including the step of determining whether or not
Even if the load torque of the motor exceeds the determination threshold value and does not exceed the determination threshold value, the fluctuation range of the load torque of the motor within a predetermined target distance range of the head moving mechanism is if exceeding the allowable variation threshold, the state determination method in the electronic component mounting apparatus characterized by determining the abnormal state which exists over a range where there is an abnormal state.

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