JP2003124239A - Electronic part mounting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part mounting device which can mitigate the restriction of allowable dimensions of a board conveying mechanism and can fast and stably make the moving operation of a transfer head. SOLUTION: In an electronic part mounting device, a chip 3 is taken out of a chip supply part 1 disposed at a lower position by a step H on a board 5 on a board conveying mechanism 4 for mounting. A head moving mechanism 8 is arranged in the arrow b direction of a down gradient toward the chip supply part 1 for moving a transfer head 9 along a rib cam 11 of a cam mechanism 6. Thus, a vertical moving stroke of the transfer head 9 can be assured without increasing an inclination of the cam curved surface of the rib cam 11 to a drive direction by the head moving mechanism 8. It is possible to mitigate the restriction of allowable dimensions of the board conveying mechanism 4 and fast and stably make the moving operation of the transfer head 9.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an electronic component mounting apparatus for taking out an electronic component cut out from a wafer and attached to an adhesive sheet and mounting it on a substrate. is there. 2. Description of the Related Art In a semiconductor device manufacturing process, a semiconductor chip is cut out from a wafer composed of a large number of chips. This chip is cut out with the wafer adhered to the adhesive sheet, and the cut out individual chip is picked up from the chip supply unit holding the wafer by the transfer head of the electronic component mounting apparatus, and is sent to the substrate transport mechanism. It is mounted on the positioned substrate. [0003] As such an electronic component mounting apparatus, there is known an apparatus in which a chip supply unit is partially vertically arranged below a substrate transport mechanism in order to shorten a moving stroke by a transfer head. I have. In the electronic component mounting apparatus having such an arrangement, a step occurs between the pickup surface of the chip supply unit and the mounting surface of the substrate positioned by the substrate transport mechanism. It is necessary to repeat the vertical movement each time the user moves between. [0004] A cam mechanism may be used as a mechanism for efficiently performing the vertical movement. This mechanism moves a cam follower that moves integrally with the transfer head along a cam curved surface having a step to perform a predetermined up and down movement, and a moving mechanism that moves the transfer head in the horizontal direction is used. Since the transfer head can also be moved up and down as a drive source, there is an advantage that the mechanism can be simplified. However, in the transfer head moving mechanism using the above-described conventional cam mechanism, the thickness of the transfer mechanism needs to be increased due to the structure of the substrate transfer mechanism. In this case, the step between the substrate transfer mechanism and the chip supply unit becomes large, and accordingly, it is necessary to increase the inclination of the cam curved surface and the curvature of the transition between the horizontal part and the inclined part. However, when the inclination or curvature of the cam curved surface is increased, the cam follower is apt to generate galling when rolling along the cam curved surface by driving in the horizontal direction, and it is difficult to realize a stable operation at high speed. For this reason, there is a limit to the level difference allowed in operation, and there is a problem that the size of the substrate transfer mechanism is restricted by this limit. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an electronic component mounting apparatus capable of relaxing the restriction on the allowable size of the substrate transfer mechanism and performing high-speed and stable movement of the transfer head. . According to a first aspect of the present invention, there is provided an electronic component mounting apparatus which transports and positions a substrate, and a step which is higher than the substrate positioned by the substrate transport mechanism. A chip supply unit disposed at a lower position, a transfer head for picking up the chips of the chip supply unit and transferring and mounting the chips on the substrate, and moving the transfer head between the substrate transfer unit and the chip supply unit A moving mechanism for moving the substrate, a first horizontal portion corresponding to a position above the substrate transfer portion, a second horizontal portion corresponding to a position above the chip supply portion, and the chip supply portion between the first and second horizontal portions. A cam member having a cam curved surface having a downwardly inclined portion; and a cam member that moves up and down with the transfer head and moves along the cam curved surface as the transfer head moves by the moving mechanism. A lower portion, and the moving mechanism is disposed at a downward gradient toward the chip supply section. According to the present invention, the moving mechanism for moving the transfer head that moves along the cam surface having a downward slope toward the chip supply section is disposed at a downward slope toward the chip supply section. The vertical movement stroke of the transfer head can be secured without increasing the inclination of the cam curved surface with respect to the driving direction of the transfer mechanism, thereby relaxing the restrictions on the allowable dimensions of the substrate transfer mechanism and speeding up the transfer head movement operation. Can be performed stably. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of an electronic component mounting apparatus according to one embodiment of the present invention. FIG. 2A is a partial front view of a cam mechanism of the electronic component mounting apparatus according to one embodiment of the present invention.
FIG. 3B is a partially enlarged view of a cam mechanism of the electronic component mounting apparatus according to the embodiment of the present invention. FIG. 3A is a partial front view of the cam mechanism of the electronic component mounting apparatus according to the embodiment of the present invention. FIG.
(B) is a partial front view of the electronic component mounting apparatus according to one embodiment of the present invention, and FIGS. 4, 5, and 6 are explanatory views of a chip mounting operation of the electronic component mounting apparatus according to one embodiment of the present invention. is there. First, the overall structure of the electronic component mounting apparatus will be described with reference to FIG. In FIG. 1, a chip 3 attached to an adhesive sheet (not shown) is held on the upper surface of a wafer holding table 2 of a chip supply unit 1. The wafer holding table 2 is horizontally movable in the direction of arrow a by a table moving mechanism (not shown). A substrate transport mechanism 4 is provided beside the chip supply unit 1. The substrate transport mechanism 4 transports and positions the substrate 5 placed on the upper surface. The wafer holding table 2 includes a substrate transport mechanism 4
The wafer holding table 2 is disposed at a lower position while securing a step H with respect to the substrate 5 positioned at a predetermined position. When the wafer holding table 2 moves horizontally, the wafer holding table 2 partially enters below the substrate transfer mechanism 4. It is possible. A cam mechanism 6 is provided above the wafer holding table 2 and the substrate transfer mechanism 4 so as to be vertically movable by a cam vertical movement mechanism 7. The cam mechanism 6 guides the horizontal movement and the vertical movement of the transfer head 9 by the cam curved surface. The transfer head 9 is driven by the head moving mechanism 8 to be guided by the cam mechanism 6 to reciprocate between the chip supply unit 1 and the substrate transport mechanism 4. By this reciprocating movement, the transfer head 9 picks up the chip 3 from the chip supply unit 1 and transfers and mounts the chip 3 on the substrate 5. Head moving mechanism 8
Is a moving mechanism for moving the transfer head 9 between the substrate transport mechanism 4 and the chip supply unit 1. The cam mechanism 6, transfer head 9, and cam vertical movement mechanism 7 will be described. A rib cam 11 (cam member) is provided at a lower end of the vertically arranged cam plate 10 in a cam shape described later. The rib cam 11 is sandwiched from above and below by a cam follower 18 connected to the block 15. The cam follower 18 moves up and down together with the transfer head 9, and the rib cam 11 is moved by the head moving mechanism 8. Move along the cam curved surface. A suction nozzle 16 is attached to a lower end of a shaft 17 fixed by inserting the block 15 up and down. The suction nozzle 16 sucks and holds the chip 3. One end of the cam plate 10 is connected to the cam vertical movement mechanism 7. The cam vertical movement mechanism 7 includes the motor 1
2 and a feed screw 1
3 is constituted by a nut 14 to be screwed. Motor 1
As the 2 rotates, the cam plate 10 coupled to the nut 14 moves up and down. Thus, the entire cam mechanism 6 moves up and down together with the transfer head 9. Next, the head moving mechanism 8 will be described.
The upper part of the shaft 17 is held by the moving block 20 in a state where sliding in the vertical direction is allowed. A slider 19 is coupled to a lower portion of the moving block 20, and the slider 19 is guided and moved by a slide rail 21 disposed at an angle in accordance with the step H. Therefore, the moving block 20 reciprocates in an oblique direction along the slide rail 21, whereby the transfer head 9 moves with the shaft 17 and the moving block 20 in a downward gradient direction indicated by an arrow b. That is, the head moving mechanism 8 is disposed at a downward gradient toward the chip supply unit 1. On the upper side of the slide rail 21, a belt 24 adjusted by a drive pulley 22 and a driven pulley 25 is disposed in parallel with the slide rail 21, and the drive pulley 22 is rotated by a motor 23 so as to rotate. The belt 24 reciprocates in the direction of arrow c. Therefore, by driving the motor 23 to rotate, the transfer head 9 moves while being guided by the cam mechanism 6. In the movement of the transfer head 9, the cam follower 18 moves along the rib cam 11, so that the transfer head 9 moves along a movement locus following the cam curved surface of the rib cam 11. Next, the cam shape of the rib cam 11 will be described with reference to FIG. As shown in FIG. 2A, the cam curved surface of the rib cam 11 includes a first horizontal portion 11 a corresponding to above the substrate transport mechanism 4, a second horizontal portion 11 c corresponding to above the chip supply portion 1, and An inclined portion 11b is provided between the first horizontal portion 11a and the second horizontal portion 11c and has a downward slope toward the chip supply portion 1. Here, the rib width B in the range of the inclined portion 11b is equal to the center distance D (FIG.
(See (b)) is set according to the state of inclination of the rib cam 11 such that the inclined rib cam 11 fits between the two fixed cam followers 18 without any gap. By driving the head moving mechanism 8,
The slider 19 reciprocates along the inclination of the slide rail 21. At this time, the cam follower 18 moves while sandwiching the rib cam 11 from above and below. When moving above the supply part 1, it moves horizontally along the first horizontal part 11a and the second horizontal part 11c. When the slider 19 reciprocates between the chip supply unit 1 and the substrate transport mechanism 4, the transfer head 9 moves obliquely along the inclined portion 11b. An external force acting on the rib cam 11 by the cam follower 18 during the oblique movement of the transfer head 9 will be described. As shown in FIG. 2B, a driving force F is applied to the upper and lower cam followers 18 in a downward gradient direction (see an arrow b shown in FIG. 1) by the head moving mechanism 8. The driving force F is divided into a component force F1 parallel to the direction in which the rib cams 11 are arranged and a component force F2 perpendicular to the direction in which the rib cams 11 are arranged. At this time, the driving force F is always
Is inclined only in the direction of the arrow b indicating the downward gradient direction, the component force F2 is smaller than that of the conventional moving mechanism in which the driving force always acts in the horizontal direction. Since the drag when the cam follower 18 is moved along the rib cam 11 depends on the vertical component F2, the smaller the component F2, the smaller the cam follower 18 becomes.
The movement is smooth. Therefore, the smaller the component force F2, the more stably the reciprocating motion between the chip supply unit 1 of the transfer head 9 and the substrate transport mechanism 4 can be performed. In order to reduce this component F2, FIG.
, Ie, the step H2 in the direction perpendicular to the downward gradient direction (arrow b) of the rib cam 11 by the head moving mechanism 8 may be reduced. In the configuration shown in this embodiment, a step H1 in the direction perpendicular to the horizontal plane, that is, a step H1 in the vertical direction in the movement of the transfer head 9, is set to be larger than the step H2 of the rib cam 11. It is possible. Therefore, the substrate transport mechanism 4 can be arranged at a sufficient step H1 with respect to the wafer holding table 2 of the chip supply section 1, and the restriction on the allowable dimension of the thickness T of the substrate transport mechanism 4 is relaxed. Next, the chip mounting operation of the electronic component mounting apparatus will be described with reference to FIGS. First, as shown in FIG. 4, the motor 23 of the head moving mechanism 8 is driven to move the moving block 20 in the direction of the arrow, and the transfer head 9 is positioned above the chip supply unit 1. Thus, the transfer head 9 moves horizontally and descends according to the cam curved surface. Next, the motor 12 of the cam vertical movement mechanism 7 is driven to lower the entire cam mechanism 6, and the suction nozzle 16 of the transfer head 9 is brought into contact with the chip 3 on the wafer holding table 2. Next, when the suction nozzle 16 holds the chip 3 by suction, as shown in FIG. 5, the entire cam mechanism 6 is raised together with the transfer head 9 by the cam vertical movement mechanism 7. Thus, the chip 3 held by the suction nozzle 16 is taken out of the wafer holding table 2. Then, the motor 23 of the head moving mechanism 8 is driven to move the moving block 20 in the direction of the arrow. As a result, the transfer head 9 moves horizontally and rises according to the cam curved surface. Then, as shown in FIG.
When the transfer head 9 further moves in the direction of the arrow and the transfer head 9 is positioned on a predetermined mounting point of the substrate 5 placed on the substrate transfer mechanism 4, the cam mechanism 6 is moved by the cam vertical movement mechanism 7. Lower the whole. Thereby, the transfer head 9 is also lowered, and the chip 3 holding the suction nozzle 16 is mounted on the substrate 5. According to the present invention, the moving mechanism for moving the transfer head that moves along the cam surface having a downward slope toward the chip supply section is arranged in a downward slope toward the chip supply section. As a result, the vertical movement stroke of the transfer head can be secured without increasing the inclination of the cam curved surface with respect to the driving direction by the moving mechanism, and the restriction on the allowable dimensions of the substrate transfer mechanism is relaxed, and the transfer head The moving operation can be performed stably at high speed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of an electronic component mounting apparatus according to an embodiment of the present invention. FIG. 2 (a) A cam mechanism of the electronic component mounting apparatus according to an embodiment of the present invention. FIG. 3B is a partial enlarged view of a cam mechanism of the electronic component mounting apparatus according to the embodiment of the present invention. FIG. 3A is a partial front view of a cam mechanism of the electronic component mounting apparatus according to the embodiment of the present invention. (B) Partial front view of an electronic component mounting apparatus according to an embodiment of the present invention. FIG. 4 is an explanatory diagram of a chip mounting operation of an electronic component mounting apparatus according to an embodiment of the present invention. FIG. 6 is an explanatory diagram of a chip mounting operation of the electronic component mounting apparatus according to the embodiment. FIG. 6 is an explanatory diagram of a chip mounting operation of the electronic component mounting apparatus according to the embodiment of the present invention. Substrate transport mechanism 5 Substrate 6 Cam mechanism 8 Head moving mechanism 9 Transfer head 11 Rib cam 16 Suction nozzle 18 Cam follower

Claims (1)

Claims: 1. A substrate transport mechanism for transporting and positioning a substrate, a chip supply unit disposed at a lower position by securing a step than the substrate positioned on the substrate transport mechanism, and A transfer head for picking up the chips of the chip supply unit and transferring and mounting the chips on the substrate, a moving mechanism for moving the transfer head between the substrate transfer unit and the chip supply unit, and A cam having a corresponding first horizontal portion and a corresponding second horizontal portion above the chip supply portion, and a slope between the first horizontal portion and the second horizontal portion and having a downward slope toward the chip supply portion; A cam member having a curved surface; and a cam follower that moves up and down together with the transfer head and moves along the cam curved surface with movement of the transfer head by the moving mechanism. An electronic component mounting apparatus characterized in that the electronic component mounting apparatus is disposed on a downward slope toward a surface.