JP4478583B2 - Electronic component mounting device - Google Patents

Description

  The present invention relates to an electronic component mounting apparatus in which an appropriate pressure can be applied to an electronic component using contact detection means for detecting that the electronic component has contacted a substrate.

  Generally, in an electronic component mounting machine, a system capable of accurately detecting mounting on an electronic component on a board is desired. In addition, there has been a demand for a pressure control system that can capture the moment when an electronic component comes into contact with the substrate and feed it back to the control system based on the warpage of the substrate and the variation in thickness of the electronic component. However, the mounting head portion of the electronic component mounting apparatus needs to be designed lightly in order to avoid the impact force on the electronic component, in addition to the swiveling and up-and-down movement, and the need for nozzle replacement.

For this reason, conventionally, as described in Patent Document 1, for example, the nozzle base is lowered at a high speed until immediately before the electronic component comes into contact with the substrate, and then the nozzle base is moved to a position where a predetermined lowering stroke is achieved. The sensor is lowered at a low speed, or a touch sensor or a pressure sensor is provided, and the touch sensor or the pressure sensor detects that the electronic base is in contact with the substrate and the nozzle base and the suction holder are relatively displaced. Thus, a technique is described in which the elevating motor is stopped after being driven for a predetermined time.
JP-A-9-148790 (paragraphs 0021 and 0025, FIGS. 1 and 3)

  However, as described in Patent Document 1 described above, in the method in which the nozzle base is lowered at a high speed until just before the electronic component comes into contact with the substrate, in order to reliably suppress the impact when the electronic component comes into contact with the substrate. In consideration of variations in the thickness of the electronic component, warpage of the substrate, etc., it is necessary to decelerate the electronic component considerably before the position where the electronic component abuts on the substrate, which causes a longer cycle time. In the method of detecting that the electronic component is in contact with the substrate, if the lowering speed of the nozzle base is increased, a compression spring for pressurization acts on the electronic component and the substrate. In order to avoid an increase in the acting impact, and lowering the lowering speed of the nozzle base, the cycle time becomes longer, and it is difficult to satisfy both the relaxation of the impact and the reduction of the cycle time.

  The present invention has been made to solve the above-described conventional problems, and can apply an appropriate pressure to an electronic component without impacting the electronic component and without increasing the cycle time. The object is to provide a component mounting apparatus.

  In order to solve the above-mentioned problem, the invention described in claim 1 includes an elevating member capable of elevating and lowering, a nozzle holder supported by the elevating member, a nozzle body provided at the tip of the nozzle holder, and the nozzle A suction head having a suction portion that is supported by the main body so as to be relatively movable in a vertical axis direction by a predetermined amount and sucks an electronic component attached to the substrate at the tip, and biases the suction head downward with respect to the nozzle body. Biasing means, contact detection means for detecting relative movement between the suction head and the nozzle body caused when the electronic component comes into contact with the substrate by lowering of the elevating member, and predetermined application of the electronic component to the substrate And a pressurizing means for pressurizing with pressure.

  According to a second aspect of the present invention, in the first aspect, the lowering speed of the elevating member is controlled based on a detection signal of the contact detection means.

  According to a third aspect of the present invention, in the second aspect, the elevating member is moved up and down via a ball screw mechanism by an elevating servo motor, and based on a detection signal of the contact detection means. The rotational speed of the lifting / lowering servomotor is controlled.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the nozzle body is provided to be movable relative to the nozzle holder in a vertical axis direction by a predetermined amount, and the pressurization is performed. The means comprises a pressure spring provided between the nozzle body and the nozzle holder, and is configured to press the nozzle body downward with respect to the nozzle holder by the spring force of the pressure spring. It is characterized by being.

  According to a fifth aspect of the present invention, in the fourth aspect of the invention, the abutment detecting means is used as a reference for the pressing amount of the pressure spring.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the contact detection means is configured by an optical system detection means supported by the elevating head. Is.

  According to the first aspect of the invention, the suction head is supported by the nozzle body provided at the tip of the nozzle holder so that the suction head can be moved by a predetermined amount, and the biasing means for biasing the suction head downward with respect to the nozzle body. Therefore, even if the electronic component sucked and held by the suction head is brought into contact with the substrate at a high speed, only the biasing force of the suction head and the biasing means having a small mass is applied to the electronic component and the substrate. Therefore, even when the electronic component is brought into contact with the substrate at a high speed, the impact can be kept small, and the cycle time of the pressure mounting operation of the electronic component can be shortened. .

  According to the invention of claim 2, since the pressurizing means is configured to pressurize the nozzle body downward with respect to the nozzle holder, by moving the nozzle body relative to the nozzle holder, There is an effect that it is possible to control the pressure of the electronic component against the substrate.

  According to the second aspect of the present invention, since the descending speed of the elevating member is controlled based on the detection signal of the contact detection means, the thickness of parts varies or the board warps. Even if it occurs, there is an effect that the descending speed of the elevating member can be appropriately switched according to the thickness of the component and the warping state of the substrate without giving an impact to the electronic component and the substrate.

  According to the third aspect of the present invention, the rotational speed of the lifting / lowering servomotor that lifts and lowers the lifting member via the ball screw mechanism is controlled based on the detection signal of the contact detection means. There is an effect that the lowering speed of the elevating member can be easily controlled by controlling the rotational speed of the elevating servo motor.

  According to the fourth aspect of the present invention, the nozzle body is provided to be movable relative to the nozzle holder by a predetermined amount in the vertical axis direction, and the pressurizing means is provided between the nozzle body and the nozzle holder. Since the pressurizing spring is used, the pressurizing means can be realized with a simple configuration, and the pressurizing force can be arbitrarily controlled by the stroke control of the elevating member, so that highly accurate pressurizing control can be realized. .

  According to the fifth aspect of the present invention, since the contact detection means serves as a reference for the pressing amount of the pressure spring, the elevating member is moved to a predetermined position based on the contact detection position by the contact detection means. By lowering the pressure, the pressure can be increased with a pressure suitable for the electronic component.

  According to the sixth aspect of the present invention, since the contact detection means is constituted by an optical sensor supported by the elevating member, the relative movement between the suction head and the nozzle body can be detected in a non-contact manner. In addition, there is no need to install the sensor on the suction head or the nozzle body, and in particular, the mass of the suction head is not increased, and the suction head for each nozzle body can be easily replaced.

  A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an electronic component mounting apparatus suitable for a mounting machine for mounting, for example, a bumped electronic component W1 having a solder electrode attached to the lower surface thereof on the surface of a substrate W, and an X table 10 that can move horizontally in the X-axis direction. The Y table 11 is mounted so as to be horizontally movable in the Y-axis direction orthogonal to the X-axis direction. These tables 10 and 11 constitute a known XY table whose movement is controlled in a horizontal plane by a servo motor (not shown) via a ball screw mechanism. An elevating member 13 is mounted on the Y table 11 so as to be vertically movable in the Z-axis direction. The elevating servo motor 14 installed on the Y table 11 is controlled to move via a ball screw mechanism 15. .

  A nozzle holder 17 is supported on the elevating member 13 so as to be rotatable only around the vertical axis, and the nozzle holder 17 is slid in the axial direction on a spline sleeve 18 supported on the Y table 11 so as to be rotatable around the vertical axis. Only spline engagement is possible. A guide sleeve 19 is connected to the spline sleeve 18, and a nozzle holder 17 is guided to the guide sleeve 19 via a guide ball so as to be slidable in the vertical axis direction. The spline sleeve 18 is connected to a nozzle holder turning servo motor 21 installed on the Y table 11 via a reduction gear 20 so that the nozzle holder 17 can be turned at an arbitrary angle together with the spline sleeve 18 by the turning servo motor 21. It has become.

  As shown in detail in FIG. 2, a mounting hole 17a is formed at the tip of the nozzle holder 17, and the nozzle body 23 is fitted into the mounting hole 17a so as to be slidable in the vertical axis direction. It projects downward from the tip of the. The nozzle body 23 holds an engagement pin 24 penetrating in the diameter direction, and the engagement pin 24 can only move in the axial direction in a slit groove 17b of a predetermined length formed along the vertical axis direction of the nozzle holder 17. Is engaged. As a result, the nozzle body 23 can move relative to the nozzle holder 17 by a predetermined amount in the axial direction. A pressure spring 26 is inserted in a compressed state between the nozzle holder 17 and a spring receiver 25 that engages with the engagement pin 24, and the nozzle body 23 is normally attached to the nozzle holder by the spring force of the pressure spring 26. 17, the engaging pin 24 is held at the lower end engaged with the lower end of the slit groove 17b. A portion of the nozzle body 23 that protrudes from the lower end of the nozzle holder 17 is formed with a flange portion 23a projecting in a disk shape, and the lower surface of the flange portion 23a functions as a screen board when an electronic component is imaged from below.

  The nozzle body 23 has a bottomed cylindrical shape with an open lower end, and a cylindrical portion 28 of the suction head 27 is fitted to the nozzle body 23 so as to be slidable in the axial direction. A slit groove 28 a having a predetermined length is formed in the tube portion 28 along the axial direction, and the engagement pin 24 is penetrated through the slit groove 28 a, whereby the tube portion 28 is relative to the nozzle body 23 in the axial direction. It is movable. A spring 29 as an urging means is inserted between the bottom of the nozzle body 23 and the suction head tube portion 28 in a compressed state. The spring force of the spring 29 causes the suction head tube portion 28 to be normally attached to the nozzle body 23. On the other hand, the upper end of the slit groove 28 a is held at the descending end that engages with the engagement pin 24.

  The suction part 30 of the suction head 27 that sucks and holds the electronic component W1 by vacuum suction is attached to the lower end of the cylindrical part 28, and the vacuum passage 31 opened in the suction part 30 includes the cylindrical part 28, the nozzle body 23, and the nozzle holder. 17 is connected to a vacuum source (not shown) through passages 33, 34, and 35 formed in the respective parts. A cylindrical shielding portion 30 a that blocks an optical axis, which will be described later, is formed at the upper end of the suction portion 30. When the cylindrical portion 28 moves relative to the nozzle main body 23 by a predetermined amount H1, the upper end of the shielding portion 30a comes into contact with the lower end of the flange portion 23a of the nozzle main body 23.

  The lifting member 13 is provided with an optical detector mounting block 13a at a position corresponding to the tip of the nozzle holder 17, and a through hole 13b through which the tip of the nozzle holder 17 can be inserted is formed in the mounting block 13a. Yes. An optical sensor 36 is attached to the mounting block 13a. The optical sensor 36 receives a signal by receiving a projector 37 disposed on one side of the through hole 13b and an optical axis emitted from the projector 37 disposed on the other side. It is comprised from the light receiver 38 which emits. As shown in FIG. 3, the optical axis irradiated from the projector 37 is slightly smaller than the radius of the shielding part 30a of the suction part 30 with respect to the center line L1 passing through the center of the nozzle body 23, and It is set so as to pass on a line L2 that is biased by a dimension S larger than the lower radius.

  Thus, in a state where the suction head 27 is held at the lower end with respect to the nozzle body 23, the optical axis is received by the light receiver 38 without being blocked by the shielding portion 30a of the suction head 27, and the received light amount is A corresponding signal is output (ON). However, when the suction head 27 is retracted relative to the nozzle body 23, the optical axis is blocked by the shielding portion 30a of the suction head 27 and is not received by the light receiver 38, and the output of the light receiver 38 is OFF. Become. As described above, the optical sensor 36 including the light projector 37 and the light receiver 38 detects the relative movement between the suction head 27 and the nozzle body 23. The spring 29 is set to a spring force sufficiently smaller than the spring force of the pressure spring 26 so as not to give an impact even when the electronic component W1 abuts against the substrate W by the biasing force.

  In FIG. 4, reference numeral 50 denotes a control device, and the control device 50 includes a microprocessor 51 and a memory 52 having a calculation function. The memory 52 mainly includes a control program for mounting electronic components and a substrate W. Pressure data set for each electronic component W1 is stored. Further, the control device 50 receives a signal from the optical sensor 36 and outputs various signals including a deceleration signal to the motor control unit 53 that controls the lifting servomotor 14.

  Next, the operation of the first embodiment in the above configuration will be described with reference to FIG. First, the XY tables 10 and 11 are driven in a state where the electronic component W1 is sucked and held on the suction head 27, and the elevating member 13 is placed on the cream solder (not shown) on the substrate W at a position corresponding to the electronic component W1. Positioned. Further, if necessary, the nozzle holder turning servo motor 21 is driven to turn the nozzle holder 17 to a predetermined angular position to position the electronic component W1 with respect to the substrate W at a predetermined angular position.

  Subsequently, the lifting / lowering servomotor 14 is driven, and the nozzle holder 17 is lowered at a high speed together with the lifting / lowering member 13 by the ball screw mechanism 15. Accordingly, the suction head 27 that sucks and holds the electronic component W1 is lowered at high speed, and the electronic component W1 comes into contact with the substrate W (state shown in FIG. 5A). At this time, the electronic component W1 is brought into contact with the substrate W only by the suction head 27 having a small mass and the spring 29 having a small spring force, so that even if the electronic component W1 contacts the substrate W at a high speed, Impact can be kept small.

  When the electronic component W1 comes into contact with the substrate W, the further lowering of the suction head 27 is stopped, but the nozzle body 23 together with the nozzle holder 17 is lowered while compressing the spring 29 as shown in FIG. Therefore, the cylinder portion 28 of the suction head 27 is moved relative to the nozzle body 23. As a result, the shielding portion 30a of the suction portion 30 is retracted relative to the mounting block 13a of the elevating member 13, so that the optical axis irradiated from the projector 37 is blocked by the shielding portion 30a of the suction portion 30 and receives light. The output signal of the device 38 changes from the ON state to the OFF state. The output signal of the light receiver 38 is input to the control device 50, and the control device 50 detects that the electronic component W <b> 1 has contacted the substrate W based on the change in the signal, and outputs a deceleration command to the motor control unit 53. Thereby, the descending speed of the elevating member 13 by the elevating servomotor 14 is gradually reduced from high speed to low speed. As described above, the optical sensor 36 constitutes a contact detection unit that detects the relative movement between the suction head 27 and the nozzle body 23 caused by the contact of the electronic component W1 with the substrate W.

  After the controller 50 detects the contact between the electronic component W1 and the substrate W, when the nozzle holder 17 and the nozzle body 23 are lowered by a predetermined amount, as shown in FIG. The end surface of 30a is engaged with the lower surface of the flange portion 23a of the nozzle body 23, and the lowering of the nozzle body 23 is stopped. Therefore, after that, the nozzle holder 17 is lowered with respect to the nozzle main body 23 while compressing the pressure spring 26. However, in the switching from the high speed to the low speed of the elevating member 13 described above, the end surface of the shielding portion 30a is located on the nozzle main body. Since it is completed before engaging the lower surface of the flange portion 23a of 23, a large impact does not occur even when the shielding portion 30a is engaged with the flange portion 23a.

  By the way, after the control device 50 detects the contact between the electronic component W1 and the substrate W based on the change in the output signal of the optical sensor 36 (contact detection means), the shielding portion 30a is engaged with the flange portion 23a. Distance “H1-α” (where α is the relative movement amount between the suction head 27 and the nozzle body 23 until the control device 50 detects contact between the electronic component W1 and the substrate W). Therefore, the control device 50 can recognize the position where the pressure spring 26 starts to be compressed by detecting the rotation amount of the lifting / lowering servomotor 14 after detecting the contact by an encoder (not shown). . In addition, by controlling the downward stroke amount of the elevating member 13 from the position where the pressure spring 26 starts to compress, the spring force (pressing force) of the pressure spring 26 to be applied to the electronic component W1 is applied to the electronic component W1. It becomes possible to control to an appropriate value in accordance with it. That is, the contact detection by the contact detection means (36) is used as a reference for controlling the pressing amount of the pressure spring 26.

  Therefore, as shown in FIG. 5D, the lifting member 13 is lowered to a predetermined position programmed by the lifting servo motor 14 based on the contact detection position by the contact detection means (36). As a result, the electronic component W1 can be pressed against the substrate W with an appropriate pressure (spring force of the pressure spring 26). As a result, the pressing force of the electronic component W1 against the substrate W can be made appropriate according to the type of the electronic component W1 and the adhesive strength of the cream solder, and the damage to the electronic component W1 and the scattering of the cream solder are effective. It is possible to mount the electronic component W1 at a high speed while preventing it.

  When the elevating member 13 is lowered to a predetermined position where the spring force of the pressure spring 26 reaches a predetermined value, the elevating servo motor 14 is stopped, and in this state, the suction holding of the electronic component W1 by the suction head 27 is released. Is done. Thereafter, the lifting servo motor 14 is reversely rotated to raise the lifting member 13 by rapid traverse and return to the original position.

  As described above, even when the electronic component W1 is brought into contact with the substrate W at high speed, the impact of the electronic component W1 on the substrate W can be reduced, so that the electronic component W1 and the substrate W can be reduced without impacting the electronic component W1. The cycle time of the pressure mounting operation can be shortened. In addition, since the electronic component W1 is brought into direct contact with the substrate W and then switched from the high speed to the low speed, it is possible to cope with the case where the thickness of the component varies or the substrate W is warped. .

  FIG. 6 shows a second embodiment of the present invention. The difference from the first embodiment is that the contact detection means is composed of a reflective optical sensor, and the other parts are as follows. Basically the same.

  In FIG. 6, the nozzle holder 17 is supported by the elevating member 13 so as to be rotatable only as described in the first embodiment. A nozzle main body 23 is fitted in a mounting hole 17 a formed at the tip of the nozzle holder 17 so as to be slidable in the axial direction, and the tip protrudes from the tip of the nozzle holder 17. An engagement pin 24 penetrating in the diameter direction is held in the nozzle body 23, and the engagement pin 24 is engaged with a slit groove 17 b formed along the axial direction of the nozzle holder 17 so as to be movable only in the axial direction. . A pressure spring 26 is inserted between the spring receiver 25 engaged with the engagement pin 24 and the nozzle holder 17 in a compressed state, and urges the nozzle body 23 downward with respect to the nozzle holder 17. .

  Here, the nozzle body 23 includes a fitting tube portion 231 slidably fitted into the mounting hole 17a and a transparent tube portion having a predetermined length made of a transparent member joined to the lower end of the fitting tube portion 231. 232 and a flanged cylinder part 233 joined to the lower end of the transparent cylinder part 232, and the transparent cylinder part 232 is arranged at a position protruding from the tip of the nozzle holder 17.

  The cylindrical portion 28 of the suction head 27 that is slidably fitted into the nozzle body 23 is formed with a slit groove 28a having a predetermined length through which the engagement pin 24 penetrates along the axial direction. It can move relative to the main body 23 in the axial direction. A compression spring 29 is inserted between the nozzle body 23 and the cylinder portion 28 in a compressed state, and urges the cylinder portion 28 of the suction head 27 downward with respect to the nozzle body 23. Here, the cylindrical portion 28 of the suction head 27 is composed of two members, a first cylindrical portion 281 and a second cylindrical portion 282 joined to the lower end of the first cylindrical portion 281, and these first and second cylinders. The joint portions of the portions 281 and 282 are usually positioned so as to correspond to the transparent tube portion 232. The appearances of the first and second tube portions 281 and 282 have colors having different reflectances.

  The lifting member 13 is provided with an optical detector mounting block 13a at a position corresponding to the tip of the nozzle holder 17, and a reflective optical sensor 361 is mounted on the mounting block 13a. The reflective optical sensor 361 irradiates the optical axis toward the cylindrical portion 28 of the suction head 27 through the transparent cylindrical portion 232 of the nozzle body 23, and normally reflects the light reflected from the first cylindrical portion 281. It is receiving light. However, when the electronic component W1 comes into contact with the substrate W and the suction head 27 is displaced backward relative to the nozzle body 23 against the spring force of the compression spring 29, it is irradiated from the reflective optical sensor 361. The reflected light is reflected by the second cylindrical portion 282. The change signal of the reflectance of the reflective optical sensor 361 is input to the control device 50, and commands the deceleration signal to the lifting servo motor that lifts the lifting member 13 by detecting the contact of the electronic component W1 with the substrate W. .

  According to the second embodiment, the relative movement of the suction head 27 with respect to the nozzle body 23, that is, the contact of the electronic component W1 with the substrate W is detected by the reflective optical sensor 361. Compared to that of the first embodiment, the detection position by the optical sensor 36 can be arranged as far as possible from the suction surface of the suction head 27, so that there are other parts on the substrate W. However, there is an advantage that the optical sensor 36 does not interfere.

  In the above-described embodiment, the relative movement between the suction head 27 and the nozzle body 23 caused by the electronic component W1 coming into contact with the substrate W is detected by the optical sensor 36. Contact with the substrate W can be detected without contact. Accordingly, since it is not necessary to install the sensor unit on a movable part such as the suction head 27, the mass of the suction head 27 is not increased, and the suction head 27 for each nozzle body 23 can be easily replaced. It is not always necessary to detect the contact between the electronic component W1 and the substrate W with an optical sensor, and a wide variety of other sensors can be used.

  Moreover, in the above-described embodiment, the example in which the deceleration of the descending speed of the elevating member 13 is started based on the detection of the contact between the electronic component W1 and the substrate W has been described. Based on the detection of contact during deceleration, the elevating member 13 is lowered so that the deceleration is changed so that the speed is not applied when the shield 30a engages the flange 23a. The speed may be controlled.

  In the above-described embodiment, the example in which the suction head 27 is urged downward by the spring force of the spring 29 with respect to the nozzle body 23 has been described. However, as the urging means for urging the suction head 27 downward. Is not particularly limited to a spring, and can be replaced with one having an equivalent function.

  Furthermore, in the above-described embodiment, the configuration in which the pressure applied to the electronic component W1 is applied using the spring force of the pressurizing spring 26 has been described, but the pressurizing means controls the spring force of the pressurizing spring 26. In addition to the configuration, it can also be configured by controlling the rotational torque of the rotary motor or controlling the thrust of the fluid pressure cylinder.

1 is an overall view of an electronic component mounting apparatus showing a first embodiment of the present invention. It is an enlarged view which expands and shows the principal part of FIG. It is sectional drawing cut | disconnected along the AA line of FIG. It is a figure which shows a control block. It is explanatory drawing explaining the action | operation of the 1st Embodiment of this invention. It is sectional drawing of the electronic component mounting apparatus which shows the 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... X table, 11 ... Y table, 13 ... Elevating member, 13a ... Mounting block, 14 ... Servo motor for raising / lowering, 15 ... Ball screw mechanism, 17 ... Nozzle Holder, 21 ... Servo motor for turning, 23 ... Nozzle body, 24 ... Engagement pin, 26 ... Pressure spring, 27 ... Suction head, 28 ... Cylinder, 29 ..Biasing means (spring), 30... Adsorption part, 36 .. contact detecting means (optical sensor), 37... Projector, 38. ... Board, W1 ... Electronic components.

Claims (6)

Elevating member capable of ascending / descending, nozzle holder supported by the elevating member, nozzle main body provided at the tip of the nozzle holder, and a substrate at the tip supported by the nozzle main body so as to be relatively movable in a vertical axis direction. A suction head having a suction portion for sucking an electronic component mounted on the nozzle, a biasing means for biasing the suction head downward with respect to the nozzle body, and the electronic component is placed on the substrate by lowering the lifting member. An electronic device comprising: contact detecting means for detecting relative movement between the suction head and the nozzle body caused by contact; and pressurizing means for pressurizing the electronic component against the substrate with a predetermined pressure. Component mounting device. 2. The electronic component mounting apparatus according to claim 1, wherein the lowering speed of the elevating member is controlled based on a detection signal of the contact detection means. 3. The lift member according to claim 2, wherein the lift member is lifted and lowered by a lift servo motor via a ball screw mechanism, and the rotation speed of the lift servo motor is controlled based on a detection signal of the contact detection means. An electronic component mounting apparatus characterized by being made. 4. The nozzle body according to claim 1, wherein the nozzle body is provided to be movable relative to the nozzle holder in a vertical axis direction by a predetermined amount, and the pressurizing unit includes the nozzle body and the nozzle holder. An electronic component mounting characterized in that the nozzle body is pressed downward with respect to the nozzle holder by a spring force of the pressure spring. apparatus. 5. The electronic component mounting apparatus according to claim 4, wherein the contact detection means serves as a reference for the pressing amount of the pressure spring. 6. The electronic component mounting apparatus according to claim 1, wherein the contact detection means is constituted by an optical system detection means supported by the elevating member.

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