JPH0427198A - Parts sucking condition detector in surface mounter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a surface mounting machine equipped with a suction nozzle that suctions components to be mounted on a circuit board and releases the suction at a predetermined mounting position. The present invention relates to a device for detecting the state of a picked-up component.

[Prior Art] In recent years, there has been an increasing demand for electronic circuits that constitute various electronic devices to be able to more densely package small components. In line with this demand, the component mounting technology has shifted from the bottle insertion method to the surface mounting method. In other words, in the bottle insertion method, a large number of through holes are drilled in the printed board,
In contrast to the surface mount method, in which the leads of circuit components such as resistors, capacitors, and ICs are inserted into the holes from the front side of the board and the protruding ends of each lead are soldered, the surface mount method inserts the resistors and other circuit components at predetermined positions on the printed circuit board. Install the circuit elements and ICs and solder the leads. Therefore, there is no need to drill holes, and the leads of circuit elements can be shortened, making it suitable for high-density mounting of miniaturized components. As a means of realizing this kind of surface mounting,
A surface mounter is used.

In a surface mounter, a necessary component is suctioned to a vacuum nozzle at a predetermined component extraction position, and the suction state (for example, the position and inclination of the component with respect to the suction nozzle) is detected. Then, if there is any positional deviation, it is corrected, the suction is released at a predetermined component mounting position, and the component is mounted on the circuit board.

For this reason, the surface mounter includes a component suction device, a moving mechanism and a positioning mechanism for the component suction device, a detection device that detects the suction state of the component, and the like.

In a conventional surface mounter, when detecting the suction state of a component, the nozzle that has suctioned one component is moved to a fixed sensor position in the surface mounter to detect the suction state.

[Problem to be solved by the invention] However, according to the conventional detection method, the position of the sensor is fixed, so in order to detect the suction state of the component, the suction nozzle must be moved to the sensor position each time. It is necessary to do so.

On the other hand, a space is required to place the sensor inside the surface mounter, and due to the structure of the surface mounter, the position where the component is picked up by the suction nozzle, the position where the component is mounted on the circuit board, and the position of the sensor are kept close to each other. It is difficult to place the In addition, it is difficult to place the sensor on a straight line connecting the component extraction position and the component mounting position, so when detecting the suction state of the component, the suction nozzle must take the shortest path from the component extraction position to the component mounting position. This resulted in the suction nozzle having to travel a long distance.

As a result, between the time the parts are taken out and the time they are installed,
A waiting time is required to move the suction nozzle to the sensor position and to position it, and a waiting time is also required for the sensor to detect the state of the component after the positioning.

Furthermore, there is a problem in that the mechanism of the surface mounter becomes large in order to take up the space necessary for mounting the sensor and the movement range of the suction nozzle.

The present invention has been made in view of the above problems, and
In a surface mounting machine equipped with a component suction nozzle, the suction state of the component can be detected while the suction nozzle moves along the shortest path from the component pick-up position to the component mounting position, thereby eliminating time loss and performing surface mounting. The purpose of this invention is to provide a detection device that can reduce the size of the machine.

[Means for Solving the Problems] In order to achieve the above object, the present invention is configured such that a sensor section for detecting the state of a suctioned component is attached to a mechanism section including a suction nozzle. That is, the detection device of the present invention includes a suction nozzle that is rotatably provided around an axis in the longitudinal direction and formed to suction a component at its tip; a nozzle rotating means for rotating the suction nozzle, a nozzle moving means for moving and positioning the suction nozzle between a component pick-up position and a component mounting position, a measuring means for measuring the state of the component suctioned by the suction nozzle, and the measuring means It is comprised of a measurement drive means for moving the means between a measurement position close to the suction nozzle and a standby position a predetermined distance from this position and positioning the means at the measurement position.

The measurement means includes a camera section that captures an image of the component sucked at the tip of the suction nozzle, and an optical system block including a lens that is close to the tip of the suction nozzle at the measurement position and introduces the image of the component into the camera section. It can be composed of

[Function] According to the present invention, when the suction nozzle suctions a necessary component at a predetermined component extraction position, the nozzle moving means is activated to move the suction nozzle to the component mounting position, while the measurement drive means is activated. The measurement means is moved from the standby position to the measurement position close to the suction nozzle and positioned. Here, the measuring means detects the suction state of the component, for example, the position and inclination of the component with respect to the suction nozzle. Through this detection, if there is any positional deviation, it is corrected. After the detection, the measurement drive means returns the measurement means from the measurement position to the standby position, and then,
When the suction nozzle reaches the component mounting position, it releases suction at the component mounting position and mounts the component on the circuit board.

In this way, the suction state of the component is detected while the nozzle that has suctioned the component is moving along the shortest path from the component take-out position to the component mounting position.

[Embodiment] FIG. 1 shows the entire surface mounting machine equipped with the detection device of the present invention, and FIGS. 2 to 4 are diagrams showing the mounting head peripheral mechanism including the detection device of the embodiment.

In Figure 1, 1 surface mounter 1 has a double door 2 on the front side.
It consists of components on a base plate (table) 3 placed on a cabinet 2 equipped with cabinets 2a and 2b, and components housed inside the cabinet 2.

On the top surface of the table 3, a robot 5 equipped with a component mounting head 4, which will be explained in detail later, a belt conveyor 7 for moving a printed circuit board 6, and a belt conveyor 7 for transporting various components (chips) of the same type to be mounted on each board. A large number of tape cartridges 8 taped together, a tape tweeter 10 for feeding the taped parts of each cartridge 8 to a take-out position on a feeder base 9, a CRT II for monitoring, a keyboard 12 operated by an operator, a robot operation panel 13, etc. Inside the cabinet 2, a controller 14 and an image processing device 15, which will be described later, are installed.

The robot 5 includes a Z-axis slide block 16 (FIG. 2) that supports the loading head 4 and moves it in the vertical direction (Z-axis direction) perpendicular to the table 3, and a belt conveyor. 7 and an X-axis arm 17 that moves in a direction parallel to X-axis arm 1
It consists of a Y-axis arm 18 that moves the entire conveyor belt 7 in a direction perpendicular to the belt conveyor 7 (Y-axis direction).

The X-axis arm 17 slidably supports a hollow prismatic biaxial base 19 in which the Z-axis slide block 16 is vertically movably housed. At the upper end of the Z-axis base 19,
A Z-axis motor 2o for moving the Z-axis slide block 16 in the Z-axis direction is installed, and inside the Z-axis base 19,
As shown by the broken line in FIG. 1, a ball screw mechanism 21 that converts the rotation of the Z-axis motor 20 into vertical movement of the Z-axis slide block 16 is housed. In addition, the X-axis arm 17
Inside, there is an X-axis motor 22 and a Z-axis base 19 that controls its rotation.
A ball screw mechanism 23 for converting movement in the X-axis direction is housed. One end of the X-axis arm 17 slides along the Y-axis arm 18, and the other end slides along the horizontal axis of a gate-shaped guide member 24 installed parallel to the Y-axis arm 17 on the table 3. freely supported. Furthermore, a Y-axis motor 25 and a ball screw mechanism 26 that converts the rotation of the Y-axis motor 25 into movement of the X-axis arm 17 in the Y-axis direction are housed in the Y-axis arm 18 . AC servo motors are used for the three motors 20, 22, and 25, respectively.

Therefore, the Z-axis slide P block 16 to which the mounting head 4 is attached is driven by the two-axis motor 20 to rotate the two-axis base 19.
It moves in the Z-axis direction along the X-axis arm 17 along with the Z-axis base 19 by driving the It moves along the Y-axis arm 18 together with the X-axis arm 17 in the Y-axis direction.

The robot 5 also has an X-axis arm 17, a Y-axis arm 18,
and the Z-axis by each ball screw mechanism of the base 19 and the encoder built in each motor 22, 25 and 20.
Positions on the Y-axis and Z-axis are detected and fed back to the controller 14.

Next, as shown in FIGS. 2 and 3, the component mounting head 4 includes an L-shaped helad base 3o fixed to the lower end of the Z-axis slide block 16, and a nozzle installed on one side of the L-shaped helad base 3o. The indexing mechanism 31 includes an indexing mechanism 31 and a pulse motor 32 attached to the opposite side of the head base 3o as its driving source.

The nozzle index mechanism 31 has a cylindrical rotating housing 33 as its main body, and has an equal angle (in this case, 12
It has three types of suction nozzles 34, 35, and 36 arranged to protrude radially at intervals of 0°). These nozzles have different diameters, and in the embodiment, nozzle 34
has the largest diameter, nozzle 35 has the middle diameter, and nozzle 36 has the smallest diameter.

Further, as shown in FIG. 4, a nozzle index mechanism 31
A positioning cylinder 37 installed on the outer peripheral surface of the one-turn housing 33, an index and an index that are movably attached to the cylinder 37 and connected to a plunger 38 protruding from the cylinder 37 via a connecting member 39. Nozzle selection positioning bin 40 and housing 3
a circular rotating plate 41 adjacent to the end face of the housing 3;
A rotary shaft 4 rotatably penetrates along the central axis of 3.
2.

A rotary plate 41 is fixed to one end of the shaft 42, and a belt pulley 43 is fixed to the other end, and as shown in FIG. A belt 45 is wound between them to transmit the rotation of the pulse motor 32 to the shaft 42.

The rotating plate 41 is provided with at least one hole 46 (three holes in the figure) into which the tip of the positioning pin 40 is inserted in order to rotate the housing 33. On the other hand, the head base 30 has each suction nozzle (large, medium).

After setting the small) 34, 35, and 36 to the lower suction position, use the positioning bin 40 to fix the housing 33.
Three holes 47a, 47b (Fig. 2) into which the proximal end of the 4
7c (not shown) is provided. This head base 3
0 is used as a housing fixing part.

Therefore, for example, as shown in Fig. 2, the suction nozzle C is large).
34 is set to the lower suction position, the positioning bottle 40 has its base end inserted into the hole 47a on the head base 3o side corresponding to the suction nozzle (large) 34. When switching the suction nozzle from this state, for example, when switching the suction nozzle (middle) 35 to the suction position, move the positioning bin 40 to the left in FIG. It is pulled out from the hole 47a corresponding to the suction nozzle (large) 34, and the tip of the positioning bottle 40 is inserted into the hole 46 (in the case of the figure, any of the three holes may be used) of the rotary plate 41. Thereby, the rotating plate 41 and the housing 33 are drivingly connected. That is, since the rotation of the shaft 42 is transmitted to the housing 33 via the rotating plate 41 and the positioning pin 40, the housing 3 is driven by the pulse motor 32.
3 can be rotated. In this case, housing 3
3 rotates until the positioning bin 40 comes to the hole 47b corresponding to the suction nozzle (middle) 35 on the Herad base 30 side,
After the rotation has stopped, the positioning pin 40 is moved in the opposite direction to the above and the tip thereof is removed from the hole 46 of the rotary plate 41.
Insert it into the hole 47b on the head base side, which is the proximal end. As a result, the housing 33 is fixed to the head base side again.
The suction nozzle (middle) 35 is set at the suction position.

As shown in FIG. 4, each suction nozzle 34, 35, 36 is located at the tip of a rotating shaft 49 that is rotatably installed around the center line inside a cylindrical portion that extends radially outward from the rotating housing 33. The rotating shaft 4 is inserted and fixed into the
It communicates with an air vent (vacuum outlet) 51 formed on the side surface of the cylindrical portion through an elongated passage 50 formed in the center of the cylinder. When in use, by sucking air through the air vent 51 using a vacuum pump or the like,
The component 52 is sucked at the tip of the suction nozzle 34.

A bevel gear 53 is fixed to the base end of the rotating shaft 49 extending toward the center of the rotating housing 33 , and this gear 53 is connected to the bevel gear 5 fixed to the rotating shaft 42 .
It meshes with 4. Therefore, the rotation of the shaft 42 driven by the pulse motor 32 causes the bevel gear 5 to rotate.
4 and 53 and each suction nozzle 3 via the rotating shaft 49.
4.35.36 rotates.

Therefore, in the embodiment, as described above, the rotating shaft 49 and the mechanism for rotationally driving it constitute a nozzle rotating means that rotates the suction nozzle about its longitudinal axis,
The mechanism for driving the mounting head 4 and the nozzle index mechanism 31 constitute a nozzle moving means for moving and positioning the suction nozzle between the component pick-up position and the component mounting position.

By the way, the tip of each cylindrical portion extending outside of the rotary housing 33 is covered with a light diffusing plate 60, and each suction nozzle 34.3
5.36 passes through this light diffusing plate 60. Light for illuminating the tip of the suction nozzle when detecting the suction state of a component is sent to the light diffusion plate 60 from a direction perpendicular to the suction nozzle. The light diffusing plate 60 diffuses or reflects light incident from one side of the plate downward, so as shown enlarged in FIGS. 5 and 6, the area around the light diffusing plate 60 is Except for the light source 64 side, it is formed as a reflective film 61 or a reflective surface 62.

The illumination device that illuminates the light diffusing plate 60 includes a casing 63 having an opening on the light diffusing plate 60 side, and a plurality of light sources (in this case, three light sources) disposed inside the casing 63 as shown in FIG. The casing 63 is attached to an optical system block 65.

The optical system block 65 consists of an L-shaped rectangular cylindrical housing, and plane mirrors 66 and 67 with reflective surfaces facing inward are disposed at the lower end and corners, respectively. A circular transparent plate 68 is attached to a portion of the optical system block 65 located above the plane mirror 66 on the lower tip side to form a light transmission window. On the other hand, a telephoto lens 69 is housed inside the upwardly extending portion of the optical system block 65, and a close-up ring 70 and a CCD (charge coupled device) camera 71 are arranged above it.

Therefore, the light emitted from the light source 64 of the lighting device is transmitted to the light diffusing plate 6
When viewed from the CCD camera 71, the component 52 attracted to the tip of the nozzle is uniformly illuminated from above.
The component 52 can be captured as a stable image via two plane mirrors 66 and 67.

The optical system block 65 is attached to a block support 72 fixed to the lower end of the biaxial base 19 so as to be slidable in the X-axis direction, and is moved by a drive mechanism including an air cylinder 73 shown in FIG. The position of the optical system block 65 is detected by a pair of position detectors 74 (one of which is shown in FIG. 4) arranged at both ends of the air cylinder 73.

Note that a buffer 75 is installed on the upper surface of the block support section 72.

Therefore, in the embodiment, as described above, an optical system including a camera 71 that captures an image of the component sucked at the tip of the suction nozzle, and a lens that introduces the image of the component into the camera 71 at a measurement position close to the tip of the suction nozzle. The system block 65 constitutes a measuring means for measuring the state of the component picked up by the suction nozzle, and the drive mechanism of the optical system block 65 moves the measuring means to a measurement position close to the suction nozzle and a predetermined distance away from this position. It constitutes a measurement drive means for moving the measurement device to the standby position and positioning the measurement device to the measurement position.

FIG. 7 shows one cycle operation of the mounting head section,
The steps will be explained in order as follows.

■The mounting head 4 is moved by the operation of the robot 5 shown in Fig. 1.
It moves to the parts removal position on the feeder base 9 and descends to a predetermined height. Then, the nozzle selected for the component 52 sent to the pick-up position by the tape feeder IO is the suction position, that is, the suction nozzle (large) in FIG.
If the nozzle is not at the position 34, the housing 33 is rotated until the nozzle is at the suction position, and then the component 52 is suctioned to the tip of the nozzle by vacuum suction.

(2) The mounting head 4 rises and moves toward a predetermined component mounting position, that is, a position on the printed circuit board 6 carried by the belt conveyor 7. At this time, the optical system block 65 is moved (advanced) to the left in the figure, and its tip is positioned directly below the component 52 sucked by the nozzle.

■Rotate the nozzle that picked up the component 52 and transfer the component to the board 6.
Set the mounting angle above. Here, the attitude of the component, that is, the position and inclination of the component is measured.

This measurement is accomplished by sending an image of the part captured by the CCD camera 71 to the image processing device 15 for processing, and making a determination using the controller 14.

■If correction is required as a result of measurement, optical system block 6
5 to the right (backward), the mounting position or inclination of the component is corrected by moving the mounting head 4 itself on the xY plane or rotating the nozzle that has picked up the component.

(2) The mounting head 4 descends, positions the component on the printed circuit board 6, stops the suction of the nozzle, and releases the nozzle to atmospheric pressure, thereby mounting the component on the circuit board.

■When the mounting head 4 rises and the next component is to be mounted,
Move to the parts removal position.

The feature of the above operation is that the head that picks up the component performs image measurement and correction operations (operations in ■ and ■ above) of the component on the route that transports the component from the component pick-up position to the mounting position, which reduces the mounting time. The aim is to shorten the time.

Figure 8 shows an example of the state of the suction nozzle and the part when measuring the part.
, ΔY) and the inclination Δθ of the long axis of the equivalent inertial ellipsoid, data necessary for correction can be obtained.

FIG. 9 shows the hardware configuration of the controller 14.

The controller 14 is mainly composed of a personal computer 80 connected to the above-mentioned monitor CRT 11 and keyboard 12, and connected via a communication path R3232C to an image processing device 15 to which a CCD camera 71 is connected, and a bus expansion board 81 attached thereto. X-axis and Y-axis motor control circuit 83, 2-axis motor control circuit 84, θ-axis motor control circuit 85,
Receiving output signals from the output board 86, input board 87, and each motor control circuit 83, 84, 85,
An X-axis servo amplifier 88, a Y-axis servo amplifier 89, a Z-axis servo amplifier 90, and a θ-axis pulse motor driver 91 drive the corresponding X-axis motor 22, Y-axis motor 25, Z-axis motor 20, and θ-axis pulse motor 32, respectively. and an interface circuit 93 that receives the output from the output board 86 and converts it into a signal for driving the conveyor motor 92.

The output board 86 has a solenoid valve 94 that is driven by its output to operate the positioning cylinder 37, and a solenoid valve 94 that is similarly driven by the output from the output board 86 to operate the camera shift air cylinder 73 (see FIG. 2). ) is connected to a solenoid valve 95 that operates the valve. The input board 87 also includes the three nozzles 34 and 35.
．． Three sensors 96 for detecting the position of the positioning bin 36 and a sensor 97 for detecting the position of the positioning bin 40 (FIG. 4) are connected.

The personal computer 80 of the controller 14 is responsible for controlling the entire surface mounter, including motor control, sequence control, and program changes.The personal computer 80 is connected to a host computer 98 via a communication line, is a disk unit 1 that exchanges data etc. with the host computer 98 via a medium such as a flexible disk 99.
00 can also be connected.

A motor control circuit 83 connected to a personal computer 80.
84, 85 and the image processing device 15 each have independent functions, and control the three axes of the servo motor and pulse motor, and calculate the posture of the attracted parts.
0 contributes to reducing the load.

The monitor CRTII can be used for both the screen display of the personal computer 80 and the monitor screen display of the image processing device 15.

FIG. 10 is a flowchart of measurement and correction operations performed by the controller 14 when actually mounting components. In this operation, measurement and correction are repeated until the mounting angle deviation 80 on the head becomes equal to or less than a certain value.

To explain the flowchart, the controller 14
First, initial values are input to the adsorption miss counter and retry counter.

Next, it is checked whether the value of the suction miss counter is O, and if it is 0, the process is abnormally terminated. If it is not zero, the #11 loading head 4 is lowered in the Z-axis direction as described above and the component is taken out.

After that, it outputs a command to raise the mounting head 4 in the Z-axis direction, a command to rotate the θ-axis (the rotation axis of the suction nozzle) to the mounting angle θ, and then moves the X-axis and Y-axis to the mounting position (x , y).

Next, by moving the optical system block 65, the CCD
The camera 71 and the illumination device are shifted and wait for completion of positioning regarding the θ axis. Then, as shown by the connector ■, visual measurement is performed using the CCD camera 71, and the eighth
ΔX explained in the figure.

Obtain ΔY and Δθ. Then, it is determined whether or not these values are abnormal values, and if they are abnormal values, 1 is subtracted from the value of the suction miss counter, and the process returns to the initial check of the suction miss counter. If the values of △X, △Y and Δθ are not abnormal values,
Next, it is checked whether the retry counter is 0 or not, and if it is 0, 1 is subtracted from the value of the suction miss counter, and the process returns to the above-mentioned check of the suction miss counter.

If the retry counter is not 0, it is first determined whether 80 is larger than a predetermined value (for example, l"), and if it is larger than the predetermined value, the θ axis is rotated by -Δθ and visual measurement is performed. to obtain ΔX, ΔY, and Δθ.Then, subtract 1 from the value of the retry counter until the retry counter becomes 0.
Return to checking whether or not.

If Δθ is not larger than the predetermined value, wait for the completion of positioning on the X-axis and Y-axis, and then move the X-axis and Y-axis by −ΔX and −ΔY, respectively, and return the CCD camera 71 and the illumination device to the origin, Then, a component mounting operation is performed, and one operation is completed.

[Advantageous Effects of the Invention 1] As described above, the detection device of the present invention is a surface mounter equipped with a component suction nozzle, in which a sensor section for detecting the state of the suctioned component is attached to the suction nozzle mechanism section. Therefore, the component pick-up position and the component mounting position are placed close to each other, and the suction state of the component can be detected while the suction nozzle moves along the shortest path from the component suction position to the component mounting position. This eliminates the physical loss and greatly improves the efficiency of component mounting. Furthermore, since conventional sensor mounting requires no space and the movement range of the suction nozzle is minimized, it is possible to realize high-speed movement of the nozzle and to downsize the entire surface mounting machine.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a surface mounter according to an embodiment of the present invention, FIG. 2 is a diagram showing the configuration of a component mounting head and its surrounding area, FIG. 3 is a partially sectional plan view of the component mounting head, Fig. 4 is a partial vertical cross-sectional view showing the structure of the inside of the component mounting head and its surrounding area, Fig. 5 is a longitudinal cross-sectional view of the tip of the head, and Fig. 6 is taken along the line Ml-Vl in Fig. 5. Partially sectional bottom view, Figure 7 is an explanatory diagram of the operation of the component mounting head, Figure 8 is a diagram showing an example of the state of the suction nozzle and components during component measurement, and Figure 9 is a diagram showing the hardware configuration of the controller. Block Diagram FIG. 10 is a flowchart showing the measurement and correction operations of the embodiment. 1...Surface mount machine, 2...Cabinet, 4...
Mounted head, 5... Robot, 6... Printed circuit board, 7... Belt conveyor, 8... Tape cartridge, 9... Feeder base, lO... Tape tweeter, 11... CRT, 12...keyboard, 13
...Operation panel, 14...Controller. 15... Image processing device, 16... Z-axis slide block, 17... X-axis arm, 18... Y-axis arm. 19...Z-axis base, 20...Z-axis motor. 21.23.26...Ball screw mechanism, 22...X
Axis motor, 24... Guide member, 25... Y-axis motor, 30... Head base, 31... Nozzle index mechanism, 32... Pulse motor, 33... Housing, 34
．． 35.36... Suction nozzle, 37... Positioning cylinder, 40... Positioning bin, 41... Rotating plate, 42...
... Rotating shaft, 43.44 ... Belt wheel, 46.47.48 ... Hole, 51 ... Air vent 52
... Parts, 53.54 ... Bevel gear, 60.
...Light diffusion plate, 63...Casing, 64...
・Light source, 65...Optical system block, 66.67・
...Plane mirror, 68...Window, 71...CCD camera. 73...Air cylinder, 80...PC, 83
．． 84.85...Motor control circuit 88.89
．． 90... Servo amplifier, 91... Pulse motor driver, 94.95... Solenoid valve, 96.97... Position sensor. Figure 6 Figure 8

Claims (2)

[Claims] (1) In a device for detecting a component suction state in a surface mounter equipped with a nozzle for suctioning components to be mounted on a circuit board, the device is rotatably provided around an axis in the longitudinal direction, and has a nozzle with which the component is attached to the tip. a suction nozzle formed to perform suction; a nozzle rotation means for rotating the suction nozzle about its longitudinal axis; and a means for moving and positioning the suction nozzle between a component removal position and a component mounting position. a nozzle moving means for measuring the state of the component suctioned by the suction nozzle; and a measuring means for measuring the state of the component suctioned by the suction nozzle; A detection device comprising: a measurement drive means for moving the detection device and positioning the detection device at the measurement position. (2) The measurement means includes a camera unit that captures an image of the component sucked at the tip of the suction nozzle, and introduces an image of the component into the camera unit in close proximity to the tip of the suction nozzle at the measurement position. 2. The detection device according to claim 1, further comprising an optical system block including a lens.