JP2001077131A - Transfer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer device with transfers a magnetic work fast with low vibration and noise, generating no metal worm powder. SOLUTION: There are provided a nonmagnetic rail 1, comprising a guide surface 1a which guides, for free sliding, a first surface of a magnetic work W comprising two surfaces perpendicular to each other, a nonmagnetic metal belt 18 which is, comprising a transfer surface 18a contacting the second surface of the work W, free to move along the rail 1, a drive means for circulating the belt 18, a yoke 4 provided opposite to the guide surface 1a of the rail 1 with the belt 18 in between, and a magnet 5 which provides a magnetic force comprising a component force which tightly contacts the second surface of the work W to the belt 18 as well as the component force which contacts the first surface of the work W to the guide surface 1a of the rail 1, with the yoke 4 arranged on one magnetic pole. A part of the yoke 4, which faces the belt 18, is covered with a resin guide member 7 having wear-resistance and self-lubrication characteristics, and the resin guide member 7 supports the back side of the transfer surface of the belt 18 for free sliding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device, and more particularly to a transfer device suitable for transferring a magnetic work such as a lead frame.

[0002]

2. Description of the Related Art Conventionally, as described in Japanese Utility Model Publication No. 7-35388, as a lead frame transfer device, a lead frame is guided along the upper surface of a non-magnetic guide rail, and one side of the upper surface of the guide rail. A transfer guide device has been proposed in which a non-magnetic guide member is provided on a side edge, and magnets are embedded at appropriate intervals inside the guide member. In this case, the side edge of the lead frame is attracted by the magnetic force and comes into contact with the guide member, so that the position accuracy is excellent, and a device for preventing the lead frame from moving backward, a device for applying tension, etc. There is an advantage that it becomes unnecessary.

However, in this case, it is necessary to use a transfer means such as a feed claw for transferring the lead frame, and it is difficult to perform high-speed transfer with low vibration and low noise. Also, since the lead frame is in close contact with the guide member, frictional resistance acts between the lead frame and the guide member, and when the feed pawl is engaged with the lead frame and transferred, a large load is partially applied to the lead frame. Therefore, there is a fear that the lead frame may be elongated or deformed.

[0004] In order to solve the above problems,
As disclosed in Japanese Patent Application Laid-Open No. 9-199516, a transfer device capable of transferring a magnetic work at high speed with low vibration and low noise and capable of high-precision positioning has been proposed. This transport device
An apparatus for conveying a magnetic work having two adjacent surfaces, comprising: a non-magnetic rail having a guide surface that slidably guides a first surface of the work; and a transfer surface that contacts a second surface of the work. A non-magnetic belt movable along the rails, a driving means for driving the belt to circulate, and a part arranged at a position facing the rail with the belt interposed therebetween so as to bring the second surface of the work into close contact with the belt. A magnet for generating a magnetic force having a force and a component force for bringing the first surface of the work into contact with the rail.

[0005]

SUMMARY OF THE INVENTION In the case of the above transport device,
The magnetic work is conveyed while being attracted to a magnet (yoke) via a non-magnetic belt. In particular, when a heavy work requiring a large magnetic force is conveyed, the frictional force between the non-magnetic belt and the magnet (yoke) also increases, and the non-magnetic belt and the magnet (yoke) are worn, resulting in durability. And the transfer position accuracy is lowered. Further, there is a problem that a large driving force is required to drive the belt.

In order to increase the durability of the non-magnetic belt, it is conceivable to use a non-magnetic metal belt such as stainless steel as the belt. Stainless steel has high hardness and excellent durability, but on the other hand, wears the yoke made of a magnetic metal and generates metal powder. This metal powder becomes an abrasive, and may cause the belt to wear and break.

An object of the present invention is to provide a transfer device which can transfer a magnetic work at high speed with low vibration and low noise, does not generate metal abrasion powder, and has excellent durability.

[0008]

The above object is achieved by a transfer device according to the present invention. That is, claim 1
The first aspect of the magnetic work having two perpendicular surfaces is described below.
A non-magnetic rail having a guide surface that slidably guides the surface, and a transport surface that contacts the second surface of the work,
A non-magnetic belt movable along a rail, driving means for driving the non-magnetic belt to circulate, a yoke arranged at a position facing the guide surface of the rail with the belt interposed therebetween, and a yoke provided at one of the magnetic poles Is placed and the second of the workpiece
A magnet for generating a magnetic force having a component force for bringing the surface into close contact with the belt and a component force for bringing the first surface of the work into contact with the guide surface of the rail, wherein the belt is formed of a non-magnetic metal belt; The portion facing the non-magnetic metal belt is covered with a resin-made guide member having wear resistance and self-lubricating property, and the resin-made guide member slidably supports the rear surface of the conveying surface of the belt. A transfer device is provided.

When the non-magnetic metal belt is moved along the rails by the driving means, the work moves integrally with the belt because the second surface of the work is attracted to the conveying surface of the belt by the magnetic force of the magnet. At this time, since the first surface of the work is slidably guided by the guide surface of the rail, the work is transported while maintaining a stable posture. Therefore, the work can be transferred at high speed with low vibration and low noise. Further, since the back surface of the belt, that is, the surface facing the transfer surface is slidably supported by the resin guide member, the generation of metal wear powder due to metal contact between the belt and the yoke is prevented, and the life of the metal belt is reduced. Can be improved. In particular,
Since the resin-made guide member has abrasion resistance and self-lubricating property, it is not necessary to supply a proper lubricant at the time of use, and it can be used for a long time without lubrication. Furthermore, since a non-magnetic metal belt is used as the belt, the belt is superior in tensile strength as compared with the resin belt, can be prevented from elongating, and can be made thin.

Preferably, the resin guide member is made of any one of polyethersulfone, polyamideimide, polyetheretherketone, aromatic polyester and ethylene tetrafluoride. .
These materials have mechanical strength, fatigue resistance, creep resistance,
Because it is an engineering plastic with excellent wear and heat resistance, it does not break or deform during use.
As a resin guide member, stable characteristics can be maintained over a long period of use.

It is desirable that the width of the surface of the resin-made guide member that comes into contact with the non-magnetic metal belt be at least half the width of the non-magnetic metal belt. If the width of the surface of the guide member that contacts the belt is small, the belt bends toward the guide member, and the belt may be broken along the longitudinal direction, and the transport surface becomes convex. Therefore, by setting the width of the guide member to be equal to or more than の of the width of the non-magnetic metal belt, the belt is prevented from bending toward the guide member, and the transport surface is prevented from becoming convex.

The present invention is suitable for conveying a hoop material having a thin plate shape such as a lead frame. That is, in the case of a hoop material, when a large load is applied locally, it tends to bend or deform. However, in the method of transporting while attracting using a magnetic force as in the present invention, the hoop material is locally applied to the hoop material. It is possible to convey at a high speed without applying an excessively large load.

[0013]

1 and 2 show a first embodiment of the present invention. This transfer apparatus is used to transfer a lead frame W, which is an example of a work, in a horizontal direction. The lead frame W of this embodiment is formed by punching out a thin band-shaped magnetic metal plate (hoop material), and has a tie bar a having a feed hole at one side edge in the longitudinal direction.
On the other side edge, a plurality of terminal portions b protruding from the tie bar a in a substantially orthogonal direction are integrally formed.

The present transport device includes a rail 1 that slidably supports the lower surface (first surface) of the tie bar a of the lead frame W. The rail 1 is made of a non-magnetic material such as stainless steel, aluminum, resin or the like, and its upper surface (guide surface) 1
A may be appropriately coated with a fluororesin coating or the like in order to reduce the frictional resistance with the lead frame W.
The rail 1 is fixed to a side surface of a rail base 2 made of a nonmagnetic material by a screw or the like. A wide upper yoke 4 is fixed on the rail base 2 via a non-magnetic magnet holder 3, and a permanent magnet 5 and a lower yoke 6 are sequentially attached to a lower surface of the upper yoke 4. That is, the yokes 4 and 6 made of a magnetic material are arranged on both the N and S poles of the permanent magnet 5, and the position of the upper yoke 4 is substantially equal to the height of the guide surface 1a. In addition, the yokes 4 and 6 are long members having almost the same length as the rail base 2.
The permanent magnet 5 does not need to have a length like the yokes 4 and 6, and may be partially disposed.

On the upper surface of the upper yoke 4, a resin guide (resin guide member) 7 having the same length as the yoke 4 is fixed by screws or the like. A guide wall 7 a extending between the upper yoke 4 and a belt 18, which will be described later, extends vertically from the resin guide 7. The guide wall 7a is desirably formed as thin as about 1 mm so that the magnetic force of the permanent magnet 5 can be reliably transmitted. When the guide wall 7a is made thin, the mechanical strength is reduced. However, since the back surface of the guide wall 7a is supported by the yoke 4 and the magnet 5, the bending of the guide wall 7a is prevented. Resin guide 7
Is made of a resin material having abrasion resistance and self-lubricating properties, such as polyethersulfone, polyamideimide, polyetheretherketone, aromatic polyester, and ethylene tetrafluoride. The width D of the guide wall 7a is the belt 1
It is desirable that the width be equal to or more than の of the width of 8. For example, when a belt 18 having a width of 10 mm is used, the width of the guide wall 7a is preferably set to 5 mm or more. This guide wall 7a
Slidably supports the rear surface of the belt 18 to prevent the generation of wear powder due to metal contact between the belt 18 and the yoke 4.

Both ends in the longitudinal direction of the rail base 2 are horizontally supported by support tables 10 and 11. A drive motor 12 composed of a servomotor, a pulse motor, or the like is fixed to one support base 10. The rotating shaft 13 of the motor 12 is connected via a coupling 14 to a driving pulley 15 disposed on the upper surface of one end of the rail base 2. A rotatable driven pulley 16 is disposed on the upper surface of the other end of the rail base 2.
The rotation axis of the rail base 2 is supported by a support mechanism (not shown).
Are movably guided in the longitudinal direction. The rotating shaft of the driven pulley 16 is urged by a tension spring 17 in a direction opposite to the driving pulley 15.
A predetermined tension is applied to the belt 18.

The driving pulley 15 and the driven pulley 16
Between them, a belt 18 made of a non-magnetic metal material is wound around with tension, and is driven to rotate in the horizontal direction. As the belt 18, a non-magnetic metal belt such as stainless steel is used. The belt 18 is formed in a thin tape shape having a thickness of, for example, about 50 μm and a width of about 10 mm, and is horizontally movable in a gap between the guide wall 7 a of the resin guide 7 and the rail 1. The transfer surface (outer peripheral surface) 18 a of the belt 18 is in close contact with the end surface (second surface) of the tie bar a of the lead frame W, and the back surface (inner peripheral surface on the feed side) is slid by the guide wall 7 a of the resin guide 7. It is movably supported. Therefore, the conveying surface 18a of the belt 18
Is substantially perpendicular to the guide surface 1a of the rail 1. The belt 18 can change the feed speed of the lead frame W by drive control of the motor 12, and can perform continuous feed, tact feed, and forward / reverse switching in addition to continuous feed.

Here, the operation of the present transport device will be described. Since the yokes 4, 6 are arranged at both poles of the permanent magnet 5, the lines of magnetic force concentrate on the boundary between the yokes 4, 6 and the permanent magnet 5. In particular, since the guide surface 1a of the rail 1 is located near the boundary between the upper yoke 4 and the permanent magnet 5,
The lines of magnetic force concentrate on the tie bars a of the lead frame W sliding on the guide surface 1a.

The magnetic force of the permanent magnet 5 is as shown in FIG.
A component force X for bringing the end surface (second surface) of the tie bar a of the lead frame W into close contact with the belt 18 and a component force Y for bringing the lower surface (first surface) of the tie bar a of the lead frame W into close contact with the rail 1.
And can occur. Note that the lead frame W is effectively brought into close contact with the belt 18 and the lead frame W
In order to minimize the sliding friction between the rail 1 and
The component force X is set larger than the component force Y. Due to the attraction force of the magnet 5 as described above, the end surface (second surface) of the lead frame W comes into contact with the guide wall 7a of the resin guide 7 via the belt 18, and the lower surface (first surface) of the rail 1 guides the rail 1. The posture in contact with the surface 1a is maintained. Here, when the belt 18 is driven, the lead frame W slides on the rail 1,
It is conveyed integrally with the belt 18. Therefore, a stable posture can be maintained even when the sheet is conveyed at high speed. Further, since the belt 18 and the lead frame W are in close contact with each other over almost the entire length, a contact state can be ensured over a long distance, and a large load does not act locally on the lead frame W.
Therefore, even if the lead frame W is formed of a thin material, deformation, warping, bending, and the like of the lead frame W can be prevented. In addition, since the belt 18 as the conveying member is driven to rotate, it is possible to suppress the generation of vibration and noise as in a conventional reciprocating feed claw.

The rear surface of the belt 18 has a guide wall 7a of the resin guide 7 having a width of at least half the width of the belt 18.
As a result, the belt 18 can be prevented from being bent or broken, and metal wear powder due to contact between the belt 18 and the yoke 4 can be prevented.
The durability of the belt 18 and the yoke 4 is improved. Further, since the resin guide 7 is made of a resin having wear resistance and self-lubricating property, it can be used without lubrication for a long period of time. In addition, since the friction between the belt 18 and the resin guide 7 is small, the driving force of the motor 12 for driving the belt 18 can be reduced, and the wear of the resin guide 7 is small. Can always be kept high. Therefore, a small-sized and high-accuracy transfer device can be realized.

When the belt 18 is stopped, the lead frame W holds the stop position by the magnetic force of the magnet 5,
Even if vibrations or shocks are received in this state, the position of the lead frame W is not disturbed, and high positioning accuracy is obtained.
Therefore, when the present transport device is used in an electronic component assembling process or a characteristic measuring process, the position of the electronic component is less likely to be misaligned. Further, since a device for preventing the backward movement of the lead frame W and for providing tension is not required, the device can be reduced in size and simplified.

When the belt 18 is started from a stopped state, a predetermined starting torque is required due to the friction between the belt 18 and the resin guide 7, but the frictional resistance between the resin guide 7 and the belt 18 is extremely small. In addition, the starting torque of the motor 12 can be small. Therefore, even when the belt 18 is tact-feeded or when the forward / reverse switching drive is performed, the belt 18 can be driven by a small motor, and the startup delay can be reduced.

The above embodiments are merely examples of the present invention, and it goes without saying that various modifications are possible. Although a single unit has been described in the above embodiment, if a plurality of the units shown in FIG. 1 are connected in series, the transfer path becomes longer, and the work can be transferred between many processes. In this case, by controlling the motor of each unit, the belt of each unit can be operated synchronously. As described above, it is easy to add or delete a unit according to the equipment specifications, and the degree of design freedom is increased.

In the above embodiment, the guide surface for slidably guiding the first surface of the work is a horizontal surface, and the conveying surface of the belt in contact with the second surface of the work is the vertical surface. The guide surface may be a vertical surface. The work that can be transported in the present invention is not limited to a lead frame having a tie bar on one side as in the embodiment, but may be any magnetic work having two perpendicular surfaces.

The resin guide according to the present invention is not limited to a shape having a guide wall that is fixed to the upper surface of the upper yoke and hangs downward as in the embodiment. For example, a guide wall fixed to the upper surface of the rail base 2 and interposed between the yoke and the belt may be formed upright, or may be formed so as to cover the entire belt side surface of the yokes 4, 6 and the magnet 5. You may. Further, the width dimension of the guide wall may be equal to or less than 1/2 of the belt width, or may be larger than the belt width. In the above embodiment, the yokes 4 and 6 are arranged at both poles of the magnet 5, but the lower yoke 6 is not always necessary.

[0026]

As is apparent from the above description, claim 1
According to the invention described in the above, since the back surface of the metal belt is slidably supported by the resin guide member, even when a large suction force is required as in the case of transporting a heavy work, the belt and the yoke can be used. The generation of metal abrasion powder due to metal contact can be prevented, and the life of the metal belt can be improved. In particular,
Since the resin-made guide member has abrasion resistance and self-lubricating property, it does not need to be replenished with a lubricant at the time of use, and has a feature that it can be used for a long time without lubrication.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of a transport device according to the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG.

[Explanation of symbols]

 W Work 1 Rail 1a Guide surface 4 Upper yoke 5 Permanent magnet 7 Resin guide (resin guide member) 7a Guide wall 12 Motor 15 Drive pulley 16 Follower pulley 18 Non-magnetic metal belt

Claims (3)

[Claims] 1. A non-magnetic rail having a guide surface for slidably guiding a first surface of a magnetic work having two perpendicular surfaces, and a transfer surface contacting the second surface of the work, wherein the rail has A non-magnetic belt movable along the belt, a driving means for driving the non-magnetic belt to orbit, a yoke arranged at a position facing the guide surface of the rail with the belt interposed therebetween, and the yoke arranged at one magnetic pole A magnet for generating a magnetic force having a component force for bringing the second surface of the work into close contact with the belt and a component force for bringing the first surface of the work into contact with the guide surface of the rail, wherein the belt is a non-magnetic metal belt. Consists of
A portion of the yoke facing the non-magnetic metal belt is covered with a resin guide member having wear resistance and self-lubricating properties,
A transport device, wherein the resin guide member slidably supports the rear surface of the transport surface of the belt. 2. The resin guide member according to claim 1, wherein the resin guide member is formed of any one of polyethersulfone, polyamideimide, polyetheretherketone, aromatic polyester, and ethylene tetrafluoride. The transfer device as described in the above. 3. The conveyance according to claim 1, wherein the width of the surface of the resin guide member which is in contact with the non-magnetic metal belt is at least half the width of the non-magnetic metal belt. apparatus.