JP2021133654A - Printing pressure control device and printing pressure control method - Google Patents

Abstract

To provide a printing pressure control device and a printing pressure control method which can appropriately set a measurement position at which printing pressure is measured and control printing pressure on the basis of a measured value of printing pressure at the set measurement position.SOLUTION: The printing pressure control device comprises a measurement position setting part, a printing pressure measuring part, and an instruction value setting part. The measurement position setting part sets a plurality of measurement positions for each time of sliding so that the plurality of measurement positions for printing pressure that is measured sequentially together with sliding of a squeegee in each of a plurality of times of target sliding which are at least some of a plurality of times of sliding of the squeegee differ among the plurality of times of target sliding. The printing pressure measuring part makes a pressure sensor measure printing pressure at the plurality of measurement positions set for each time of sliding by the measurement position setting part. The instruction value setting part sets an instruction value of printing pressure in the next time of sliding, on the basis of measured values of printing pressure up to the current time of sliding having been measured by the printing pressure measuring part and a target value of printing pressure.SELECTED DRAWING: Figure 2

Description

The present specification discloses a technique relating to a printing pressure control device and a printing pressure control method.

The screen printing machine described in Patent Document 1 includes a printing pressure sensor, a data correction unit, and a print control unit. The printing pressure sensor measures the printing pressure that the circuit board receives from the squeegee in response to the pressing force. The data correction unit sets control data indicating the relationship between the squeegee position and the command value in at least a part of the print range as the target of the print pressure measured over the entire area and the preset print pressure. Correct based on the value. The print control unit controls screen printing based on the corrected control data.

International Publication No. 2014/147812

However, Patent Document 1 does not specify a method for setting a measurement position for measuring printing pressure. For example, in one sliding of the squeegee, it is necessary to shorten the sampling cycle of the printing pressure as the number of measurements of the printing pressure (the number of measurement positions) is increased, and a control device for controlling the printing pressure or the like. May increase the cost.

In view of such circumstances, the present specification appropriately sets a measurement position for measuring the printing pressure, and print pressure control capable of controlling the printing pressure based on the measured value of the printing pressure at the set measurement position. The apparatus and the printing pressure control method are disclosed.

The present specification controls the printing pressure, which is the pressure applied to the mask when the squeegee slides in the solder printing machine in which the squeegee slides the mask a plurality of times to print solder on the substrate through the mask. The printing pressure control device to be used is disclosed. The printing pressure control device includes a measurement position setting unit, a printing pressure measuring unit, and a command value setting unit. The measurement position setting unit measures a plurality of printing pressures in order as the squeegee slides in each of the plurality of target slides, which is at least a part of the plurality of slides of the squeegee. The plurality of measurement positions are set for each sliding rotation so that the positions are different in the plurality of target sliding times. The printing pressure measuring unit causes a pressure sensor to measure the printing pressure at the plurality of measuring positions set for each sliding rotation by the measuring position setting unit. The command value setting unit commands the printing pressure in the next sliding rotation based on the measured value of the printing pressure up to the current sliding rotation measured by the printing pressure measuring unit and the target value of the printing pressure. Set the value.

Further, the present specification describes a printing pressure which is a pressure applied to the mask when the squeegee slides in a solder printing machine in which the squeegee slides the mask a plurality of times to print solder on a substrate through the mask. The printing pressure control method for controlling the printing pressure is disclosed. The printing pressure control method includes a measurement position setting step, a printing pressure measuring step, and a command value setting step. In the measurement position setting step, a plurality of measurements of the printing pressure are sequentially measured as the squeegee slides in each of the plurality of target slides which are at least a part of the plurality of slides of the squeegee. The plurality of measurement positions are set for each sliding rotation so that the positions are different in the plurality of target sliding times. In the printing pressure measuring step, the pressure sensor is made to measure the printing pressure at the plurality of measuring positions set for each sliding rotation by the measuring position setting step. The command value setting step is a command of the printing pressure in the next sliding rotation based on the measured value of the printing pressure up to the current sliding rotation measured by the printing pressure measuring step and the target value of the printing pressure. Set the value.

Since the above-mentioned printing pressure control device is provided with a measurement position setting unit, it is possible to set a plurality of measurement positions for each sliding rotation so that a plurality of measuring positions for printing pressure are different in a plurality of target slides. can. Further, since the above-mentioned printing pressure control device includes a printing pressure measuring unit and a command value setting unit, the printing pressure is controlled based on the measured value of the printing pressure at the measurement position set by the measuring position setting unit. Can be done. The same applies to the printing pressure control method as described above for the printing pressure control device.

It is sectional drawing which shows the structural example of a solder printing machine. It is a block diagram which shows an example of the control block of a printing pressure control device. It is a flowchart which shows an example of the control procedure by a printing pressure control device. It is a system diagram which shows an example of the control system which measures the printing pressure and controls the printing pressure based on the measured value of the printing pressure. It is a schematic diagram which shows the setting example of the measurement position of a printing pressure. It is a schematic diagram which shows an example of the relationship between the printing pressure and the position of a squeegee. It is a schematic diagram which shows the structural example of the command value setting part. It is a schematic diagram which shows the control example of a printing pressure.

1. 1. Embodiment 1-1. Configuration Example of Solder Printing Machine 1 In the solder printing machine 1 of the present embodiment, the solder 80 is moved along the mask 70 by the squeegee 34, and the printing process is executed on the substrate 90. The solder printing machine 1 is included in a substrate working machine that produces a substrate product by performing a predetermined substrate working on the substrate 90. The solder printing machine 1 constitutes a board production line together with a board-to-board working machine such as a printing inspection machine, a component mounting machine, a reflow furnace, and a visual inspection machine.

As shown in FIG. 1, the solder printing machine 1 includes a substrate transfer device 10, a mask support device 20, a squeegee moving device 30, a display device 40, and a control device 50. In the present specification, the transport direction of the substrate 90 (the direction perpendicular to the paper surface of FIG. 1) is the X-axis direction, and the front-rear direction of the solder printing machine 1 orthogonal to the X-axis in the horizontal plane (the left-right direction on the paper surface of FIG. 1) is defined as the X-axis direction. The Y-axis direction is defined, and the vertical direction (vertical direction on the paper surface of FIG. 1) orthogonal to the X-axis and the Y-axis is defined as the Z-axis direction.

The substrate transfer device 10 conveys the substrate 90 to be printed. The substrate 90 is a circuit board on which an electronic circuit, an electric circuit, a magnetic circuit, and the like are formed. The substrate transfer device 10 is provided on the base 2 of the solder printing machine 1. The substrate transfer device 10 conveys the substrate 90 arranged on the pallet by, for example, a belt conveyor extending in the X-axis direction. The substrate transfer device 10 includes a substrate holding unit 11 that holds the substrate 90 carried into the solder printing machine 1. The substrate holding portion 11 holds the substrate 90 at a predetermined position on the lower surface side of the mask 70 in a state where the upper surface of the substrate 90 is in close contact with the lower surface of the mask 70.

The mask support device 20 is arranged above the substrate transfer device 10. The mask support device 20 supports the mask 70 by a pair of clamp members (one clamp member is shown in FIG. 1). The pair of clamp members are arranged on the left side and the right side of the solder printing machine 1 in the front direction, and are formed so as to extend along the Y-axis direction. Note that FIG. 1 is a partial cross-sectional view of the solder printing machine 1 cut along the Y-axis direction, and schematically shows the inside of the solder printing machine 1 in the side view and the cross sections of the mask 70 and the substrate 90. It is shown. The mask 70 is formed with an opening 71 that penetrates at a position corresponding to the wiring pattern of the substrate 90. The mask 70 is supported by the mask support device 20 via, for example, a frame member provided on the outer peripheral edge.

The squeegee moving device 30 raises and lowers the squeegee 34 in a direction perpendicular to the mask 70 (Z-axis direction), and moves the squeegee 34 in the Y-axis direction on the upper surface of the mask 70. The squeegee moving device 30 includes a head driving device 31, a squeegee head 32, a pair of elevating devices 33, 33, and a pair of squeegees 34, 34. The head driving device 31 is arranged above the solder printing machine 1. The head drive device 31 can move the squeegee head 32 in the Y-axis direction by, for example, a linear motion mechanism such as a feed screw mechanism.

The squeegee head 32 is clamped and fixed to a moving body constituting the linear motion mechanism of the head drive device 31. The squeegee head 32 holds a pair of elevating devices 33, 33. Each of the pair of elevating devices 33, 33 holds the squeegee 34 and can be driven independently of each other. Each of the pair of elevating devices 33, 33 drives, for example, an actuator such as a servomotor or an air cylinder to elevate the squeegee 34 to be held.

The pair of squeegees 34, 34 slide on the upper surface of the mask 70 to move the solder 80 supplied to the upper surface of the mask 70 along the mask 70. As the solder 80, cream solder (solder paste) can be used. The solder 80 is imprinted on the substrate 90 through the opening 71 of the mask 70, and the solder 80 is printed on the substrate 90 arranged on the lower surface side of the mask 70. In the present embodiment, each of the pair of squeegees 34, 34 is a plate-shaped member formed so as to extend along the X-axis direction orthogonal to the printing direction (Y-axis direction).

Of the pair of squeegees 34, 34, the squeegee 34 on the front side (left side of the paper surface in FIG. 1) is used for the printing process of moving the solder 80 from the front side to the rear side, and is used from the front side to the rear side of the solder printing machine 1. The direction of travel is the direction of travel. Of the pair of squeegees 34, 34, the squeegee 34 on the rear side (right side of the paper surface in FIG. 1) is used for a printing process for moving the solder 80 from the rear side to the front side, and is used for a printing process from the rear side to the front side of the solder printing machine 1. The direction toward is the direction of travel. Further, in any of the squeegees 34, the direction opposite to the traveling direction is set as the retreating direction.

Each of the pair of squeegees 34, 34 is held by the elevating device 33 so as to be inclined so that the front portion located on the traveling side faces downward. In other words, each of the pair of squeegees 34, 34 is held by the elevating device 33 at an angle so that the back surface portion located on the retracting side faces upward. The inclination angle of each of the pair of squeegees 34, 34 is adjusted by an adjustment mechanism provided in the lower part of the elevating device 33.

The display device 40 can display the working status of the solder printing machine 1. Further, the display device 40 is composed of a touch panel, and also functions as an input device that accepts various operations by the user of the solder printing machine 1.

The control device 50 includes a known arithmetic unit and a storage device, and constitutes a control circuit. The control device 50 is communicably connected to the management device via a network, and can transmit and receive various data. The control device 50 drives and controls the substrate transport device 10, the mask support device 20, the squeegee moving device 30, and the display device 40 based on the production program, the detection results detected by various sensors, and the like.

As shown in FIG. 2, when the control device 50 is regarded as a control block, the measurement position setting unit 51, the printing pressure measurement unit 52, the command value setting unit 53, the interpolation unit 54, the storage unit 55, and so on. It includes a setting unit 56 and a print control unit 57. Further, the control device 50 is provided with a storage device 50 m. A description of the measurement position setting unit 51, the printing pressure measurement unit 52, the command value setting unit 53, the interpolation unit 54, the storage unit 55, and the resetting unit 56 will be described later.

The print control unit 57 drives and controls, for example, the squeegee moving device 30. The print control unit 57 acquires various information stored in the storage device 50 m and detection results of various sensors provided in the solder printing machine 1. As the storage device 50m, for example, a magnetic storage device such as a hard disk device, a storage device using a semiconductor element such as a flash memory, or the like can be used. The storage device 50m stores a production program for driving the solder printing machine 1.

The print control unit 57 sends a control signal to the squeegee moving device 30 based on the above-mentioned various information and detection results. Thereby, the position and height (position in the Z-axis direction) of the pair of squeegees 34, 34 held in the squeegee head 32 in the printing direction (Y-axis direction), as well as the moving speed and the tilt angle are controlled.

1-2. Example of kneading process and printing process When the substrate 90 is carried in by the substrate transport device 10 and the substrate 90 is arranged at a predetermined position on the lower surface side of the mask 70, the kneading process and the printing process are executed. Specifically, at the start of the printing process, the solder 80 is supplied to the upper surface of the mask 70. As shown in FIG. 1, in the solder 80, a solder roll 81 is formed by a kneading process.

The solder roll 81 is formed by kneading paste-like cream solder by alternately moving a pair of squeegees 34 and 34 in the traveling direction. The solder roll 81 is a solder 80 in a state in which the squeegee 34 is stretched in the length direction (X-axis direction) and the width in the printing direction (Y-axis direction) is substantially uniform. In the following description, the solder roll 81 is appropriately described as the solder 80.

The print control unit 57 first executes the preparatory step. One of the pair of squeegees 34, 34 is designated as the first squeegee. Further, the other squeegee 34 of the pair of squeegees 34, 34 is referred to as a second squeegee. In the preparation step, the first squeegee is positioned at a predetermined position (height) retracted above the mask 70. Further, the first squeegee is positioned at a predetermined position on the receding side of the solder roll 81 in the Y-axis direction.

Next, the print control unit 57 executes the squeegee lowering step to lower the first squeegee to the printing position (height) where the lower end of the first squeegee contacts the mask 70. As a result, the first squeegee comes into contact with the mask 70 with a predetermined pressure. Subsequently, the print control unit 57 drives and controls the head drive device 31 to execute the printing process.

The print control unit 57 moves the first squeegee in the traveling direction while maintaining the above-mentioned print position (height) in the printing process. Then, the solder roll 81 supplied to the upper surface of the mask 70 is moved along the mask 70 as the first squeegee moves. At this time, the solder roll 81 is imprinted on the substrate 90 through the opening 71 of the mask 70, and the solder 80 is printed on the upper surface of the substrate 90 arranged on the lower surface side of the mask 70.

After the first squeegee has passed the predetermined print range, the print control unit 57 drives and controls the elevating device 33 to execute the squeegee ascending step. In the squeegee raising step, the first squeegee is separated from the solder roll 81. At this time, the print control unit 57 raises the first squeegee at a predetermined movement speed along a predetermined movement locus. The movement locus and the movement speed are set based on, for example, the physical properties of the solder roll 81 in use. Next, the print control unit 57 switches from the first squeegee to the second squeegee and repeats the above printing process so that the squeegee head 32 reciprocates in the Y-axis direction. As described above, in the solder printing machine 1 of the present embodiment, the squeegee 34 slides the mask 70 a plurality of times to print the solder 80 on the substrate 90 via the mask 70.

1-3. Configuration Example of Printing Pressure Control Device 100 The printing pressure control device 100 includes a measurement position setting unit 51, a printing pressure measuring unit 52, and a command value setting unit 53. The printing pressure control device 100 may also include at least one of an interpolation unit 54, a storage unit 55, and a resetting unit 56. As shown in FIG. 2, the printing pressure control device 100 of the present embodiment includes a measurement position setting unit 51, a printing pressure measurement unit 52, a command value setting unit 53, an interpolation unit 54, a storage unit 55, and the like. It is provided with a setting unit 56.

Further, the printing pressure control device 100 of the present embodiment executes control according to the flowchart shown in FIG. The measurement position setting unit 51 performs the process shown in step S11. The printing pressure measuring unit 52 performs the process shown in step S12. The command value setting unit 53 performs the process shown in step S14. The interpolation unit 54 performs the process shown in step S13. The storage unit 55 performs the process shown in step S15. The resetting unit 56 performs the determination shown in step S16 and the process shown in step S17.

Further, the printing pressure control device 100 makes the determination shown in step S18, and repeats the processing and determination shown in steps S12 to S17 until the kneading process is completed. The printing pressure control device 100 can also repeat the processing and determination shown in steps S12 to S17 until the printing processing is completed. The printing pressure control device 100 can be provided in various control devices. The printing pressure control device 100 of this embodiment is provided in the control device 50 of the solder printing machine 1. The printing pressure control device 100 can also be provided in a management device that manages a plurality of board-to-board working machines including the solder printing machine 1. The printing pressure control device 100 can also be formed on the cloud.

1-3-1. Configuration example of the control system 60 In the printing pressure control device 100, the squeegee 34 slides in the solder printing machine 1 in which the squeegee 34 slides the mask 70 a plurality of times to print the solder 80 on the substrate 90 via the mask 70. The printing pressure, which is the pressure sometimes applied to the mask 70, is controlled. FIG. 4 shows an example of a control system 60 that measures the printing pressure and controls the printing pressure based on the measured value of the printing pressure.

The control system 60 of the present embodiment includes a pressure sensor 61, a signal conversion device 62, a control device 50, a driver device 63, and a pair of elevating devices 33 and 33. In the figure, one elevating device 33 is illustrated, and in this specification, one elevating device 33 and one squeegee 34 are described, but the same applies to the other elevating device 33 and the squeegee 34. ..

The pressure sensor 61 may take various forms as long as it can measure the printing pressure. As the pressure sensor 61, for example, a known load cell can be used. The load cell can detect distortion, light, string vibration, capacitance, inductance, etc., and measure the force generated in the detected body or the force received by the detected body. The pressure sensor 61 of the present embodiment is provided on the piston rod that raises and lowers the squeegee 34 in each of the pair of elevating devices 33 and 33. The pressure sensor 61 uses a load cell having a strain generating body and a strain gauge that distort in proportion to the stress generated in the piston rod, and is the reaction of the force (printing pressure) applied to the mask 70 when the squeegee 34 slides. The force can be measured.

The voltage output from the pressure sensor 61 (voltage proportional to the stress generated in the piston rod) is input to the signal conversion device 62. The signal conversion device 62 acquires the input voltage (analog signal) at a predetermined sampling cycle and converts it into a digital signal. The print pressure measurement information (print pressure measurement value) converted into a digital signal by the signal conversion device 62 is transmitted to the control device 50.

The control device 50 is provided with a printing pressure control device 100, and controls the printing pressure based on the measured value of the printing pressure. Details of the control by the printing pressure control device 100 will be described later. The driver device 63 generates a drive signal of the drive device that raises and lowers the piston rods of the pair of elevating devices 33 and 33 based on the command value of the printing pressure set by the printing pressure control device 100. For example, as shown in FIG. 4, when the drive device for raising and lowering the piston rod includes the electric motor 33a, the driver device 63 generates a drive signal for rotationally driving the electric motor 33a.

As the electric motor 33a, for example, a known servomotor can be used. In this case, the driver device 63 can use a known servo amplifier. In the drive device shown in FIG. 4, the feed screw mechanism 33b moves (elevates) the piston rod in the Z-axis direction to raise and lower the squeegee 34 provided at the tip of the piston rod. Specifically, when the motor 33a rotates in a predetermined rotation direction, the squeegee 34 moves in the direction closer to the mask 70 (downward in the Z-axis direction on the paper surface of FIG. 4), and the printing pressure is higher than that before the movement. It gets higher. On the contrary, when the motor 33a rotates in the direction opposite to the predetermined rotation direction, the squeegee 34 moves in the direction away from the mask 70 (upward in the Z-axis direction on the paper surface of FIG. 4), and the printing pressure is higher than that before the movement. Will be low.

1-3-2. Measurement position setting unit 51
For example, in one sliding of the squeegee 34, it is necessary to shorten the sampling cycle of the printing pressure so as to increase the number of measurements of the printing pressure (the number of measurement positions), and the control device for controlling the printing pressure. There is a possibility that the cost of 50 or the like will increase. Further, it is necessary to increase the communication speed between the signal conversion device 62 and the control device 50 so as to increase the number of measured printing pressures (the number of measurement positions) in one sliding of the squeegee 34. Therefore, there is a possibility that the cost of the control device 50 or the like for controlling the printing pressure will increase.

Therefore, the printing pressure control device 100 of the present embodiment includes a measurement position setting unit 51. The measurement position setting unit 51 measures a plurality of measurement positions of the printing pressure in order as the squeegee 34 slides in each of the plurality of target slides, which is at least a part of the plurality of slides of the squeegee 34. A plurality of measurement positions are set for each sliding rotation so that is different in a plurality of target sliding times (step S11 shown in FIG. 3). The target sliding may be all the sliding in the kneading process or a part of the sliding in the kneading process. Further, the target sliding may be all sliding in the printing process or may be a part of the sliding in the printing process.

The measurement position setting unit 51 may take various forms as long as the measurement position of the printing pressure can be set so that the plurality of measurement positions of the printing pressure are different in a plurality of times of target sliding. The measurement position setting unit 51 sets the first measurement position P1 which is a plurality of measurement positions for measuring the printing pressure in the first sliding at regular intervals, and sets a predetermined distance PL0 and the printing pressure with respect to the first measurement position P1. It is possible to set the measurement position of the printing pressure to be measured in the second and subsequent slidings by moving the measurement position of.

FIG. 5 shows an example of setting the measurement position of the printing pressure. The figure is a plan view of the mask 70, and a setting example of the first measurement position P1 and the second measurement position P2 is schematically shown. The first measurement position P1 is shown by a solid line, and is set at a constant separation distance CL0 in the printing direction (Y-axis direction). The second measurement position P2 is a plurality of measurement positions for measuring the printing pressure in the second sliding, and is shown by a broken line in the figure. The second measurement position P2 is set to a position where the measurement position of the printing pressure is moved by a predetermined distance PL0 with respect to the first measurement position P1. For example, the predetermined distance PL0 in the figure is set to half (1/2) of the separation distance CL0.

The measurement position setting unit 51 can similarly set the measurement position of the printing pressure to be measured in the third and subsequent slidings. For example, the measurement position setting unit 51 can set the predetermined distance PL0 for the measurement position of the printing pressure to be measured in the third sliding to a quarter (1/4) of the separation distance CL0. The measurement position setting unit 51 can set the predetermined distance PL0 for the measurement position of the printing pressure to be measured in the fourth sliding to one-eighth (1/8) of the separation distance CL0.

In this way, the measurement position setting unit 51 multiplies the separation distance CL0 between two measurement positions adjacent to each other in the sliding direction of the squeegee 34 at the first measurement position P1 by a coefficient that decreases as the number of slides increases. , The predetermined distance PL0 in at least one sliding after the second time can be set. In the above example, the coefficient can be expressed as ^{1/2 N-1 using the number of slides N.} The above coefficient can be set arbitrarily. For example, the above coefficient may be a coefficient that is inversely proportional to the number of slides. In this case, the coefficient can be expressed as 1 / N by using the number of slides N. In either case, the measurement position setting unit 51 can easily set the measurement position for each different sliding turn in a plurality of target slides.

FIG. 6 shows an example of the relationship between the printing pressure and the position of the squeegee 34. The horizontal axis of the figure shows the position of the squeegee 34, and the vertical axis shows the printing pressure. The straight line L11 shows an example of the target value P0_g of the printing pressure, and the curve L12 shows an example of the printing pressure measured by the pressure sensor 61. In the figure, in order to make it easy to understand the positional relationship between the squeegee 34 and the mask 70, a plan view of the mask 70 supported by the pair of clamp members 20c is also shown.

In the examples shown in the straight line L11 and the curve L12, the measured value of the printing pressure is generally smaller than the target value P0_g of the printing pressure. When the squeegee 34 moves from the left side to the right side of the paper surface in the figure and reaches the outer edge portion BP0 on the left side of the paper surface of the mask 70, the measured value of the printing pressure momentarily increases. When the squeegee 34 slides on the mask 70, the contact portion of the squeegee 34 increases, so that the measured value of the printing pressure is larger than that before the squeegee 34 reaches the mask 70.

When the squeegee 34 reaches the notch NA0 of the mask 70, the contact portion of the squeegee 34 decreases, and the measured value of the printing pressure becomes smaller than before the squeegee 34 reaches the notch NA0. When the squeegee 34 passes through the notch NA0, it returns to the state before reaching the notch NA0, and the measured value of the printing pressure increases and returns to the state before the squeegee 34 reaches the notch NA0. There is. Then, when the squeegee 34 reaches the outer edge portion BP0 on the right side of the paper surface of the mask 70, the measured value of the printing pressure once increases, then decreases, and then becomes constant.

In this way, the printing pressure varies depending on the portion of the mask 70. Therefore, the measurement position setting unit 51 sets the printing area PA0 of the substrate 90 to a predetermined number of measurement positions among the plurality of measurement positions where the printing pressure is measured by the predetermined sliding rotation. It is also possible to set a predetermined distance PL0 in at least one sliding after the first time. The print area PA0 refers to an area on the substrate 90 on which components are mounted.

For example, when the number of sliding times is 10 and 100 measurement positions are set, the predetermined distance PL0 can be set so that 95 measurement positions are set in the print area PA0 of the substrate 90. .. Specifically, it is assumed that when the measurement position of the printing pressure is moved by a predetermined distance PL0 with respect to the first measurement position P1, the measurement position of the printing pressure is set in the cutout portion NA0 of the mask 70. In this case, the measurement position setting unit 51 can change (increase or decrease) the predetermined distance PL0 to set the measurement position in the print area PA0 of the substrate 90. As a result, the measurement position setting unit 51 can set a predetermined number of measurement positions in the print area PA0 of the substrate 90, which easily affects the print quality.

The measurement position setting unit 51 is the outer edge of the mask 70 in which the squeegee 34 first or last contacts the mask 70 at a predetermined number of measurement positions among the plurality of measurement positions where the printing pressure has been measured by the predetermined sliding rotation. A predetermined distance PL0 in at least one sliding after the second time can be set so as to be set in the part BP0 or the cutout part NA0 of the mask 70. The measurement position setting unit 51 sets a predetermined number of measurement positions (for example, 5 in the above example) to the outer edge portion BP0 in the same manner as in the case of setting a predetermined number of measurement positions in the print area PA0 of the substrate 90. Alternatively, it can be set to the notch portion NA0. As a result, the measurement position setting unit 51 can set a predetermined number of measurement positions in a region where the printing pressure is likely to fluctuate.

1-3-3. Printing pressure measuring unit 52
The printing pressure measuring unit 52 causes the pressure sensor 61 to measure the printing pressure at a plurality of measuring positions set for each sliding rotation by the measuring position setting unit 51 (step S12 shown in FIG. 3).

As described above, the head drive device 31 shown in FIG. 1 can move the squeegee head 32 in the Y-axis direction by, for example, a linear motion mechanism such as a feed screw mechanism. The linear motion mechanism is provided with a position detector such as an encoder. The printing pressure measuring unit 52 can know the position of the squeegee 34 in the printing direction (Y-axis direction) based on the position of the squeegee head 32 detected by the position detector. The printing pressure measuring unit 52 has a plurality of measuring positions set for each sliding rotation by the measuring position setting unit 51 from the measurement information of the printing pressure acquired when the squeegee 34 reaches the measuring position and converted into a digital signal. It is possible to obtain the measured value of the printing pressure in.

The printing pressure measuring unit 52 is a pressure sensor when the solder printing machine 1 is performing the kneading process of kneading the solder 80, which is a pretreatment before producing the substrate product in which the components are mounted on the substrate 90. The printing pressure can be measured by 61. As a result, the printing pressure control device 100 can acquire the relationship between the measured value of the printing pressure and the target value of the printing pressure before the printing process for producing the substrate product is performed. Further, the printing pressure control device 100 can control the printing pressure by using the above-mentioned relationship acquired in the kneading process when the sliding rotation is small in the printing process when producing the substrate product. Print quality can be ensured from an early stage.

Further, the printing pressure measuring unit 52 causes the pressure sensor 61 to measure the printing pressure when the printing process for producing the substrate product in which the components are mounted on the substrate 90 is being performed in the solder printing machine 1. You can also. In this case, the printing pressure control device 100 can acquire the relationship between the measured value of the printing pressure and the target value of the printing pressure when the printing process for producing the substrate product is being performed. Therefore, for example, the printing pressure control device 100 can control the printing pressure according to the amount of solder even if the amount of solder decreases with the production of the substrate product and the above relationship fluctuates. The printing pressure measuring unit 52 causes the pressure sensor 61 to measure the printing pressure when the kneading process is performed in the solder printing machine 1, and the pressure is measured when the printing process is performed in the solder printing machine 1. It is also possible to have the sensor 61 measure the printing pressure.

1-3-4. Command value setting unit 53
The command value setting unit 53 sets the command value of the printing pressure in the next sliding rotation based on the measured value of the printing pressure up to the current sliding rotation and the target value of the printing pressure measured by the printing pressure measuring unit 52. (Step S14 shown in FIG. 3).

The command value setting unit 53 feedback-controls the printing pressure so as to cancel the difference between the measured value of the printing pressure up to the current sliding rotation measured by the printing pressure measuring unit 52 and the target value of the printing pressure, and next time. It is possible to set the command value of the printing pressure in the sliding rotation of. Further, as the feedback control, at least proportional control among proportional control, integral control and differential control can be used.

FIG. 7 shows a configuration example of the command value setting unit 53. As shown in the figure, the command value setting unit 53 includes a subtractor 53a and a feedback control unit 53b. The target value P0_g of the printing pressure and the measured value P0_s of the printing pressure measured up to the sliding rotation this time are input to the subtractor 53a. The subtractor 53a outputs the deviation ΔP0 of the printing pressure by subtracting the measured value P0_s of the printing pressure from the target value P0_g of the printing pressure. The deviation ΔP0 of the printing pressure is input to the feedback control unit 53b. The feedback control unit 53b performs at least proportional control among proportional control, integral control, and differential control, and outputs a command value P0_ref of the printing pressure.

For example, assume that the control gain (proportional gain) of proportional control is set to 1. In this case, when the measured value P0_s of the printing pressure is smaller than the target value P0_g of the printing pressure and the deviation ΔP0 of the printing pressure is positive, the feedback control unit 53b sets the deviation ΔP0, which is the shortage of the printing pressure, as the target of the printing pressure. The command value P0_ref of the printing pressure added to the value P0_g is set to increase the printing pressure. On the contrary, when the measured value P0_s of the printing pressure is larger than the target value P0_g of the printing pressure and the deviation ΔP0 of the printing pressure is negative, the feedback control unit 53b sets the deviation ΔP0, which is the excess of the printing pressure, as the target of the printing pressure. The command value P0_ref of the printing pressure subtracted from the value P0_g is set to lower the printing pressure.

The control gain is set, for example, between zero and one. The larger the proportional gain, the shorter the deviation ΔP0 can be. Further, as the control gain (integral gain) of the integral control is increased, the offset (steady state deviation) due to the deviation ΔP0 can be eliminated in a short time. Further, as the control gain (differential gain) of the differential control is increased, the vibration of the deviation ΔP0 can be converged in a short time and becomes stronger against the disturbance. These control gains may be acquired in advance by simulation, adjustment by an actual machine, or the like.

As shown in FIG. 7, the command value P0_ref of the printing pressure in the next sliding rotation is input to the driver device 63. The driver device 63 generates a drive signal of the drive device that raises and lowers the piston rod of the elevating device 33 based on the command value P0_ref of the printing pressure. As the piston rod moves (elevates) in the Z-axis direction, the squeegee 34 provided at the tip of the piston rod moves up and down, and the printing pressure is increased or decreased as compared with the sliding rotation this time.

FIG. 8 shows an example of controlling the printing pressure. The horizontal axis in the figure shows the time. The vertical axis of the upper figure shows the moving speed of the squeegee 34 in the horizontal direction. The vertical axis of the middle figure shows the moving speed of the squeegee 34 in the vertical direction. The vertical axis of the lower figure shows the measured value of the printing pressure. The polygonal line L21 shows an example of a change over time in the horizontal movement speed of the squeegee 34. The polygonal line L22 shows an example of a change over time in the vertical movement speed of the squeegee 34. The black dots in the lower figure show an example of obtaining the measured value of the printing pressure.

As shown by the polygonal line L22, when the lower end portion of the squeegee 34 comes into contact with the mask 70 in the squeegee lowering step described above, a moving speed is instantaneously generated in the vertical direction of the squeegee 34. When the squeegee 34 moves in the traveling direction, the horizontal moving speed of the squeegee 34 increases (accelerates) as shown by the polygonal line L21. After that, the horizontal moving speed of the squeegee 34 becomes constant, decreases (decelerates), and one sliding of the squeegee 34 ends. As shown by the polygonal line L22, when the squeegee 34 rises in the squeegee ascending step described above, the moving speed is instantaneously generated in the vertical direction of the squeegee 34 (the direction opposite to the case of the squeegee lowering step). The same can be said for the second sliding.

The printed pressure measured value PP1 is an example of the printed pressure measured value measured in the first sliding. The measured value PP1 has a larger deviation ΔP0 from the target value P0_g of the printing pressure as compared with other measured values. The printed pressure measured value PP2 is an example of the printed pressure measured value measured in the second sliding. The printing pressure of the measured value PP2 is controlled based on the command value P0_ref of the printing pressure set by the command value setting unit 53, and the deviation ΔP0 is smaller than that of the measured value PP1. As shown by the polygonal line L22, in the figure, it is schematically shown that the printing pressure is controlled by the fluctuation of the moving speed of the squeegee 34 in the vertical direction.

1-3-5. Interpolator 54
As the number of sliding turns decreases, the measured value of the printing pressure measured by the pressure sensor 61 decreases, and the command value P0_ref of the printing pressure between two measurement positions adjacent to each other in the sliding direction of the squeegee 34 is not set appropriately. there is a possibility. For example, the command value P0_ref of the printing pressure at one measurement position is set between one measurement position and the next measurement position in the sliding direction of the squeegee 34. Therefore, the printing pressure control device 100 of the present embodiment includes an interpolation unit 54.

The interpolation unit 54 measures the printing pressure in the unset area where the measurement position has not been set by the measurement position setting unit 51 by the current sliding rotation, and the printing pressure measured by the pressure sensor 61 by the current sliding rotation. Interpolate based on the measured value (step S13 shown in FIG. 3). The interpolated print pressure measurement value is input to the subtractor 53a shown in FIG. 7 together with the print pressure measurement value P0_s measured up to this sliding rotation.

The interpolation unit 54 may take various forms as long as it can interpolate the printing pressure in the unset area. For example, the interpolation unit 54 can approximate the measured value of the printing pressure measured up to the current sliding rotation with a straight line to interpolate the printing pressure in the unset region. Further, the interpolation unit 54 approximates the measured value of the printing pressure measured up to the current sliding rotation with a curve (for example, a quadratic curve, a cubic curve, etc.) and interpolates the printing pressure in the unset area. You can also. As a result, the command value setting unit 53 can set the command value P0_ref of the printing pressure in the unset area where the measurement position is not set.

1-3-6. Memory 55
In the printing process, the moving speed of the squeegee 34 and the printing pressure are closely related. Therefore, there is a request to know the relationship between the moving speed of the squeegee 34 and the printing pressure. Therefore, the printing pressure control device 100 of the present embodiment includes a storage unit 55. The storage unit 55 stores the moving speed of the squeegee 34 and the measurement result of the printing pressure in the storage device 50 m in association with each other (step S15 shown in FIG. 3). The moving speed of the squeegee 34 means the speed at which the squeegee 34 moves in the traveling direction.

As a result, the user of the solder printing machine 1 can know the relationship between the moving speed of the squeegee 34 and the printing pressure. In addition to the measurement results of the moving speed and the printing pressure of the squeegee 34, the storage unit 55 can store various information related to printing in the storage device 50m in association with each other. For example, the information related to printing includes information for specifying the substrate 90, information for specifying the solder 80, information for specifying the mask 70, and the like.

1-3-7. Reset unit 56
For example, the measured value of the printing pressure measured by the pressure sensor 61 may include disturbance (noise). When the printing pressure is measured only once at the same measurement position, the command value setting unit 53 may continue to set the command value of the printing pressure based on the measured value of the printing pressure including the disturbance. Therefore, the printing pressure control device 100 of the present embodiment includes a resetting unit 56.

When the measurement position of the printing pressure is set up to a predetermined sliding time by the measuring position setting unit 51, the resetting unit 56 refers to the measuring position setting unit 51 with respect to the printing pressure in sliding up to the sliding time. Is set again as the measurement position of the printing pressure. Specifically, the resetting unit 56 determines whether or not the printing pressure measurement position has been set up to a predetermined sliding rotation (step S16 shown in FIG. 3). The sliding rotation for resetting the measurement position can be set arbitrarily.

When the measurement position of the printing pressure is set up to the predetermined sliding turn (Yes in step S16), the resetting unit 56 prints on the measuring position setting unit 51 in the sliding up to the sliding time. The measurement position where the pressure is measured is set again as the measurement position of the printing pressure (step S17). Even if the measured value of the printing pressure measured at the previously set measurement position contains disturbance (noise), the printing pressure measurement position is set again for the same measurement position, and the printing pressure is re-established. Be measured. Therefore, the printing pressure control device 100 can reduce the influence of the disturbance included in the measured value of the printing pressure. If the printing pressure measurement position is not set up to the predetermined sliding rotation (No in step S16), the process shown in step S17 is not performed, and the printing pressure is controlled by the determination shown in step S18. move on.

2. The pressure sensor 61 may also be provided on the side of the substrate holding portion 11. For example, the pressure sensor 61 can be provided on a backup pin that holds the substrate 90. The pressure sensor 61 can also be provided on a backup table that holds the substrate 90. Further, when the lifting device 33 raises and lowers the squeegee 34 that drives and holds the air cylinder, the printing pressure control device 100 can also control the air pressure of the air cylinder to control the printing pressure.

3. 3. Printing pressure control method The same applies to the printing pressure control method 100 as described above for the printing pressure control device 100. Specifically, the printing pressure control method includes a measurement position setting step, a printing pressure measuring step, and a command value setting step. The measurement position setting step corresponds to the control performed by the measurement position setting unit 51. The printing pressure measuring step corresponds to the control performed by the printing pressure measuring unit 52. The command value setting step corresponds to the control performed by the command value setting unit 53. The printing pressure control method may also include at least one of an interpolation step, a storage step, and a resetting step. The interpolation step corresponds to the control performed by the interpolation unit 54. The storage step corresponds to the control performed by the storage unit 55. The resetting step corresponds to the control performed by the resetting unit 56.

4. An example of the effect of the embodiment Since the printing pressure control device 100 includes the measurement position setting unit 51, a plurality of measurements are performed for each sliding rotation so that a plurality of measuring positions of the printing pressure are different in a plurality of target slides. The position can be set. Further, since the printing pressure control device 100 includes a printing pressure measuring unit 52 and a command value setting unit 53, the printing pressure is controlled based on the measured value of the printing pressure at the measurement position set by the measuring position setting unit 51. can do. The same applies to the printing pressure control device 100 as described above for the printing pressure control device 100.

1: Solder printing machine, 34: Squeegee, 51: Measurement position setting unit,
52: Printing pressure measuring unit, 53: Command value setting unit, 54: Interpolating unit,
55: Storage unit, 56: Reset unit, 50 m: Storage device,
61: Pressure sensor, 70: Mask, 80: Solder, 90: Substrate,
100: Printing pressure control device, P1: First measurement position,
PL0: predetermined distance, CL0: separation distance, PA0: print area,
BP0: outer edge, NA0: notch.

Claims (13)

A printing pressure control device that controls a printing pressure, which is a pressure applied to the mask when the squeegee slides in a solder printing machine in which the squeegee slides the mask a plurality of times to print solder on a substrate through the mask. And
In each of the plurality of target slides, which is at least a part of the plurality of slides of the squeegee, the plurality of measurement positions of the printing pressure, which are sequentially measured according to the slide of the squeegee, are the targets of the plurality of times. A measurement position setting unit that sets the plurality of measurement positions for each sliding turn so as to be different in sliding.
A printing pressure measuring unit that causes a pressure sensor to measure the printing pressure at the plurality of measuring positions set for each sliding rotation by the measuring position setting unit.
Command value setting to set the command value of the printing pressure in the next sliding rotation based on the measured value of the printing pressure up to the current sliding rotation measured by the printing pressure measuring unit and the target value of the printing pressure. Department and
A printing pressure control device. The printing pressure in the unset area where the measurement position has not been set by the measurement position setting unit by the current sliding rotation is converted to the measured value of the printing pressure measured by the pressure sensor by the current sliding rotation. The printing pressure control device according to claim 1, further comprising an interpolation unit that performs interpolation based on the basis. The printing pressure measuring unit is a pretreatment before producing a substrate product in which components are mounted on the substrate, and when the kneading process of kneading the solder is performed in the solder printing machine, the printing is performed. The printing pressure control device according to claim 1 or 2, wherein the pressure is measured. Claims 1 to claim that the printing pressure measuring unit measures the printing pressure when the printing process for producing a substrate product in which a component is mounted on the substrate is performed in the solder printing machine. The printing pressure control device according to any one of 3. The measurement position setting unit sets the first measurement position, which is the plurality of measurement positions for measuring the printing pressure in the first sliding, at regular intervals, and prints the print at a predetermined distance from the first measurement position. The printing pressure control device according to any one of claims 1 to 4, wherein the measuring position of the pressure is moved to set the measuring position of the printing pressure to be measured in the second and subsequent slidings. The measurement position setting unit multiplies the separation distance between two measurement positions adjacent to each other in the sliding direction of the squeegee at the first measurement position by a coefficient that decreases as the number of slides increases, and the second and subsequent measurement positions are set. The printing pressure control device according to claim 5, wherein the predetermined distance is set in at least one sliding. The measurement position setting unit is used for the second and subsequent times so that a predetermined number of measurement positions among the plurality of measurement positions where the printing pressure is measured by the predetermined sliding rotation are set in the printing area of the substrate. The printing pressure control device according to claim 5 or 6, wherein the predetermined distance is set in at least one sliding of the above. In the measurement position setting unit, a predetermined number of measurement positions among a plurality of measurement positions where the printing pressure has been measured by a predetermined sliding turn of the mask in which the squeegee first or last contacts the mask. The printing pressure according to any one of claims 5 to 7, which sets the predetermined distance in at least one sliding after the second time so as to be set in the outer edge portion or the notch portion of the mask. Control device. The command value setting unit feedback-controls the printing pressure so as to cancel the difference between the measured value of the printing pressure up to the current sliding rotation measured by the printing pressure measuring unit and the target value of the printing pressure. The printing pressure control device according to any one of claims 1 to 8, wherein the command value of the printing pressure in the next sliding rotation is set. The printing pressure control device according to claim 9, wherein the feedback control is at least the proportional control of proportional control, integral control, and differential control. The printing pressure control device according to any one of claims 1 to 10, further comprising a storage unit that stores the moving speed of the squeegee and the measurement result of the printing pressure in a storage device. When the measurement position of the printing pressure was set up to a predetermined sliding turn by the measuring position setting unit, the printing pressure was measured with respect to the measuring position setting unit in the sliding up to the sliding turn. The printing pressure control device according to any one of claims 1 to 11, further comprising a resetting unit for resetting the measurement position as the measurement position of the printing pressure. A printing pressure control method for controlling a printing pressure, which is a pressure applied to the mask when the squeegee slides in a solder printing machine in which the squeegee slides the mask a plurality of times to print solder on a substrate through the mask. And
In each of the plurality of target slides, which is at least a part of the plurality of slides of the squeegee, the plurality of measurement positions of the printing pressure, which are sequentially measured according to the slide of the squeegee, are the targets of the plurality of times. A measurement position setting step of setting the plurality of measurement positions for each sliding turn so as to be different in sliding, and a measurement position setting step.
A printing pressure measuring step of causing a pressure sensor to measure the printing pressure at the plurality of measuring positions set for each sliding rotation by the measuring position setting step.
Command value setting to set the command value of the printing pressure in the next sliding rotation based on the measured value of the printing pressure up to the current sliding rotation measured by the printing pressure measuring step and the target value of the printing pressure. Process and
A printing pressure control method comprising.

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