JP4395654B2 - Work positioning device - Google Patents

Description

  The present invention relates to an apparatus for positioning a workpiece such as a semiconductor chip in a correct posture at a set position.

  For example, in an assembly machine in a semiconductor manufacturing process, a semiconductor chip as a part is attached to a tape and used. In a taping machine that makes such a component placement tape, a semiconductor chip is placed in a correct position and posture in advance with respect to the tape using a workpiece positioning mechanism (alignment unit) (hereinafter referred to as positioning). Alternatively, in a semiconductor chip inspection machine, an alignment unit is used to always correctly position the chip in accordance with the position of the inspection probe.

Patent Document 1 discloses an alignment unit proposed by the applicant of the present application, in which a workpiece is positioned by driving fingers in four directions by a cam mechanism. By adopting a cam mechanism, high-speed and highly accurate work can be performed, and a spring member is interposed for driving the fingers so that the workpiece is not damaged during positioning.
Note that there are not many patent documents relating to units that are functionally specialized only for alignment, and as recent ones, Patent Documents 2 to 5 (cited in Patent Document 1), Patent Document 6 and Patent Document 7 are scattered. It is a grade.

However, this type of alignment unit often has a structure in which the fingers and their movement guide members are exposed to the work space together with the work cradle on the upper surface of the unit due to the nature of the work.
FIGS. 6 to 9 simply show the structure of the workpiece positioning device 1 in Patent Document 1 and include a motor 2 and an alignment unit 3. The alignment unit 3 includes a main body portion 4 and a finger drive mechanism 5 (FIG. 8) housed therein. The finger drive mechanism 5 is driven by the motor 2 and includes a cam mechanism 6 (FIG. 9), fingers 7, a linear guide 8 for guiding the fingers 7, and the like. The cam mechanism 6 is rotationally driven by the motor 2 and the four fingers 7 are simultaneously reciprocated in the radial direction to position the target workpiece.

  In this structure, as shown in FIG. 7, the upper portion of the main body 4 is closed by a cover 9 that also serves as a work cradle. However, a slide hole 10 is formed in the cover 9, and the finger 7 Is protruding. Reference numeral 11 is a claw, and reference numeral 12 is a target workpiece. For this reason, the finger drive mechanism 5 below the cover 9 is equivalent to being exposed to the work space.

JP 2004-106095 A Japanese Patent Laid-Open No. 01-133327 JP-A-60-172438 JP-A-57-138596 Japanese Patent Laid-Open No. 09-109081 JP-A-10-293913 JP 2000-246571 A

  When the workpiece (target workpiece) that requires positioning is an electronic component, the outer shell material is often ceramic or synthetic resin. Then, when they are brought into contact with the positioning claws, burrs and powder (referred to as dust) adhering to the workpiece are scattered around the workpiece, and in the conventional structure, adhere to the exposed mechanism on the upper surface of the alignment unit. . The dust eventually gets caught in a linear guide or a cam mechanism for smoothly moving the fingers, which may cause malfunction.

In order to avoid such a situation, it is conceivable to attach a simple dustproof cover that covers the upper surface of the alignment unit. However, dust may enter from a very small gap, and a cover that is easily deformed in the form of a sheet may come into contact with the finger drive mechanism. For example, in the alignment unit of Patent Document 1, the target workpiece is positioned by using a spring having a small output torque so that the motor load is not directly applied to the target workpiece after the target workpiece is positioned by the fingers. Therefore, when the finger is in contact with the cover during the finger operation, the sliding resistance of the finger is increased, and there is a problem that the finger stops before the spring is defeated and the target workpiece is positioned. Thus, accurate positioning cannot be performed.
Therefore, the present invention provides a workpiece positioning apparatus having an alignment unit having a main body structure that exhibits a high dustproof effect.

In a work positioning apparatus including a motor and an alignment unit, a main body structure in which the upper surface of the alignment unit is covered with a cover member is employed. The finger driving mechanism is housed inside the cover member, and a work receiving portion is provided on the upper surface of the cover member. The fingers are structured to move in the radial direction from the inside of the cover member to the outer peripheral side. On the other hand, a joint that moves in the radial direction along the upper surface of the cover member is provided to connect the fingers. Attach the claw that comes into contact with the target workpiece to the tip of the joint.
It is preferable to introduce air pressure into the cover member so that the interior of the cover member is always higher than the external pressure.

  Since the cover member is provided as the main body structure of the alignment unit and the fingers are reciprocally driven in the radial direction inside the cover member, a mechanism for guiding and driving the fingers is not exposed on the upper surface of the unit. For this reason, it is prevented that malfunctioning is caused by dust scattered from the target workpiece. Also, it is easy to make the interior of the cover member higher than the outside air pressure, and it is possible to more effectively prevent dust from entering the cover member.

The workpiece positioning device includes a motor and an alignment unit.
The alignment unit positions the target workpiece on the upper surface of the cradle with a claw that is driven and interlocked with the finger. Therefore, the alignment unit includes a cover member, a finger drive mechanism, fingers, joints, and claws.
The cover member is composed of a cylindrical outer cover and an upper cover and a seal block that hermetically cover the upper surface thereof. The finger driving mechanism is disposed inside the cover member.

One end of the finger is connected to the finger drive mechanism and attached to the seal block so as to pass through the seal block from the center of the outer cover to the outer periphery.
On the other hand, a joint that is movable in the radial direction is disposed along the upper surface of the upper cover. A claw is provided at one end of the joint and the other end of the joint is connected to the other end of the finger. A nail | claw is set as the arrangement | positioning which contacts the object workpiece | work mounted in the workpiece receiving part formed in the upper surface of an upper cover.
Air pressure is introduced into the cover member so that the internal pressure of the cover member is always higher than the outside air.

The workpiece positioning device 1 (FIG. 1) includes a motor 2 and an alignment unit 3. The motor 2 is a stepping motor in this embodiment.
The alignment unit 2 includes a main body 4, a cover member 13, and a joint 14, and a finger driving mechanism 5 (FIG. 2) and four fingers 7 are arranged on the main body 4. The finger drive mechanism 5 is the same as in the case of Patent Document 1. 2 and 3, the joint 14 is removed.

The cover member 13 (FIG. 4) includes a short cylindrical outer cover 15, an upper cover 16, and a seal block 17, and the upper surface of the outer cover 15 is hermetically closed by the upper cover 16 via a seal ring 18. The upper cover 16 is fixed to the main body 4 with screws from above (FIG. 2).
Four attachment points 19 for the seal block 17 are formed on the side wall of the outer cover 15. A notch 20 through which the finger 7 penetrates each attachment point 19, an air inlet hole 21, an air outlet hole 22, and a screw hole 23. Is formed.

  The seal block 17 has an insertion hole 24 through which the finger 7 penetrates in the center, a screw hole 25 for attachment is formed, and an air joint 26 is attached. The seal block 17 is fixed to the outer cover 15 with screws 28 (FIG. 2) at each of the attachment points 19 with a seal plate 27 interposed therebetween. At this time, the other end portion of the finger 7 whose one end is connected to the finger drive mechanism 5 is allowed to move in the radial direction through the insertion hole 24 of the seal block 17, and the end portion is exposed to the outside. That is, the fingers 7 protrude outward from the side wall of the outer peripheral cover 15 and move in the radial direction. The insertion hole 24 is connected to the notch 20 of the outer peripheral cover 15 and communicates with the inside of the outer peripheral cover 15. An air flow path from the air joint 26 is also communicated with the inside of the outer peripheral cover 15.

In this embodiment, the finger 7 is a round shaft and includes a stepped portion 29 at the tip, and the insertion hole 24 of the seal block 17 is larger than the diameter of the finger 7 except for the tip. (Figure 5).
The outer surface of the stepped portion 29 of the finger 7 is a tapered surface 30, and the opening edge of the seal block 17 is also the inner surface of a tapered surface 31 opposite to this, and when the finger 7 moves most outward, These tapered surfaces 30 and 31 are close to each other so as to suppress dust intrusion as much as possible.
Inside the step 29, a rubber packing 32 is attached. The rubber packing 32 is of a type that reduces the diameter when the air pressure on the outer peripheral cover 15 side increases and opens the air flow path on the outer side.
Further, an air suction port is formed in the insertion hole 24 of the seal block 17 on the outer side of the rubber packing 32, and an air joint 34 can be attached thereto (FIG. 3).

The joint 14 (FIG. 1) is L-shaped with a vertical portion 35 and a horizontal portion 36, and is connected to the outer end portion of the finger 7 by slitting the lower end of the vertical portion 35. Thereby, the horizontal part 36 can move in the same radial direction as the finger 7 along the upper surface of the outer peripheral cover 15, that is, the upper surface of the upper cover 16 together with the movement of the finger 7, and the claw 11 is attached to the tip. Reference numeral 37 denotes a work cradle, which is fixed to the upper surface of the upper cover 16.
In the above structure, the upper surface of the alignment unit 3 is closed by the cover member 13, and the fingers 7 protrude from the outer cover 15 to the side.

When using the workpiece positioning device 1, the power source and the air source are connected after being installed at a predetermined position. Note that all or a part of the air joints 26 may be used. The unused air inlet hole 21 is plugged. Since the air suction port 33 is used when necessary, it is always closed.
When the motor 2 is driven, the finger 7 is reciprocated in the radial direction at the timing set by the finger driving mechanism 5, whereby the claw 11 on the upper surface of the cover member 13 is moved via the joint 14 and supplied to the workpiece cradle 37. The operation of positioning the target workpiece 12 is repeated.

This example exhibits the following excellent effects.
Even if the target workpiece 12 generates dust, the upper surface of the alignment unit 3 is closed by the cover member 13, and the penetrating portion where the finger 7 protrudes from the outer peripheral cover 15 is lateral to the cover member 13. The possibility that dust will reach the inside of the cover member 13 is extremely low.

Since the cover member 13 has a main body structure and the seal block 17 can be attached to the outer peripheral cover 15, the dustproof effect can be further enhanced as necessary.
The rubber packing 32 disposed between the inner wall of the insertion hole 24 and the finger 7 reduces the diameter and widens the flow path when the flow rate of air is large, so that a large amount of air is sent toward the opening end of the insertion hole 24. be able to.
The stepped portion 29 and the rubber packing 32 provided on the finger 7 have a function of a stopper for blocking dust that has entered from the opening end of the insertion hole 24 and an action of pushing back this outward. The dust pushed back in this way and accumulated near the end of the insertion hole 24 is sucked from the air suction port 33 and discharged to the outside at regular intervals set according to the situation.

The part where the air blows out from the inside of the cover member 13 is the side surface of the outer peripheral cover 15 and is far from the work cradle 37 on the upper surface of the cover member 13, so that the position of the positioned target work 12 is not shifted by air blow. .
Since the sealing method is non-contact by air blow, the thrust of the finger 7 required for positioning does not change, and stable positioning accuracy can be maintained over a long period of time.
When the seal member (seal block 17 or rubber packing 32) is consumed by dust, it is possible to replace only the seal member independently from the cover member 13 which is the structure on the main body side, and it is easy to maintain and improve the sealing effect. Inexpensive.

Since the shape of the finger 7 is a round shaft and the connection with the claw 11 is performed by the joint 14, the claw shape is not limited and a free shape can be selected according to the workpiece shape and positioning specifications.
Conventionally, it was intended for handling a small work, but the size of the work that can be handled is increased because the fingers 7 are on the side.
The seal block can be replaced with an appropriate one in accordance with the size, material, shape, etc. of the dust generated from the target workpiece 12, and there is no need to replace the alignment unit itself.

  As a result of the sealing of the penetrating portion of the finger 7 with the seal block 17 and the inside of the cover member 13 being kept higher than the external air pressure by the supplied air pressure, the internal air from the opening end of the insertion hole 24 in the seal block 17 Flows out and dust is prevented more effectively from entering the cover member 13.

A is a front view of the whole, B is a partial side view as seen from the arrow Plan view Front view (partial cross section) Exploded perspective view Partial enlarged front view (partial cross section) Front view (conventional example) Plan view (conventional example) Plan view (conventional example) Plan view (cam)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Work positioning device 2 Motor 3 Alignment unit 4 Main body part 5 Finger drive mechanism 6 Cam mechanism 7 Finger 8 Linear guide 9 Cover 10 Slide hole 11 Claw 12 Target work 13 Cover member 14 Joint 15 Outer cover 16 Upper cover 17 Seal block 18 Seal Ring 19 Mounting point 20 Notch 21 Air inlet 22 Air outlet 23 Screw hole 24 Insertion hole 25 Screw hole 26 Air joint 27 Seal plate 28 Screw 29 Step 30 Tapered surface (finger)
31 Tapered surface (insertion hole)
32 Rubber packing 33 Air suction port 34 Air joint 35 Vertical portion 36 Horizontal portion 37 Work receiving base

Claims (6)

  It includes a motor and an alignment unit, and the alignment unit includes a cover member, a finger drive mechanism, fingers, joints, and claws, and positions the target workpiece on the upper surface of the cradle with the claws that are driven and interlocked with the fingers. The cover member is composed of a cylindrical outer cover and an upper cover that hermetically covers the upper surface of the cover member. The finger drive mechanism is disposed inside the cover member, and the finger is connected to the finger drive mechanism at one end thereof. A work receiving part formed on the upper surface of the upper cover at one end of the joint, which is mounted so that it can be driven back and forth from the center of the cover to the outer periphery and vice versa. Claw that comes into contact with the target workpiece placed on the Positioning device of a work which is characterized in that are connected to the other end of the chromatography.   2. The work positioning apparatus according to claim 1, wherein air pressure is introduced into the cover member so that the pressure inside the cover member is always higher than the outside air.   A seal block provided with an insertion hole for penetrating the finger is attached to a portion where the finger penetrates the outer periphery cover to cover the penetration portion and to allow the penetration portion and the insertion hole to communicate with each other, and between the inner wall of the insertion hole and the finger. The work positioning apparatus according to claim 2, wherein an annular rubber packing is mounted so that the diameter can be reduced by an atmospheric pressure from the inside.   The finger has a stepped shape, the outer surface of the stepped portion is formed into a tapered surface, and the inner wall of the opening portion of the insertion hole is formed into a tapered surface opposite to this, and the finger reaches the moving end in the outer circumferential direction. 4. The workpiece positioning device according to claim 3, wherein the tapered surface of the finger and the tapered surface of the insertion hole are close to each other, and the air flow path of the insertion hole is reduced.   5. The positioning device according to claim 4, wherein an air joint is attached to the seal block, and an air flow path from the air joint is communicated with the inside of the cover member. The positioning according to any one of claims 3 to 5, wherein a preliminary air port is formed outside the annular rubber packing in the insertion hole through which the finger passes, and air can be sucked from this portion. apparatus.

Images