JP2002173250A - Suction carrying method and suction machining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suction carrying method and a suction machining method hardly causing unstable image recognition with the influence of a suction face and permitting highly precise control. SOLUTION: The suction carrying method utilizing the result of image recognition of a carried material 4 for carrying control when carrying the carried material 4 being sucked and fixed to the suction face of a suction plate 3 with the movement of the suction plate 3 comprises forming the suction face of the suction plate 3 with a porous sheet 5 having a thickness of 0.1-3 mm consisting of a sintered porous body of super high molecular weight polyethylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for adsorbing and conveying an adsorbing plate used for adsorbing and conveying, wherein the adsorbing surface of the adsorbing plate is formed of a porous sheet made of a sintered porous material of ultra high molecular weight polyethylene (UHMWPE). And the suction processing method, in particular, flexible circuit boards (FPC) used for electronic equipment, thin-layer sheets, transport of other circuit boards,
This is a useful technique for fixing applications during processing.

[0002]

2. Description of the Related Art In the processing of precision cutting of a glass plate for liquid crystal or a semiconductor wafer, precise coating on a glass plate for liquid crystal or a semiconductor wafer, precision bonding of a polarizing plate and a retardation plate, or precision bonding of these and a glass plate. These workpieces are fixed so as not to be displaced.

[0003] A vacuum suction method is often employed for fixing such a workpiece. In this method, for example, as shown in FIG. 1, a suction plate (made of a material having mechanical strength such as metal) 3 provided with a predetermined number of suction holes 1 on an upper surface and provided with suction connection portions 2 at predetermined positions. The workpiece 4 is placed on the porous sheet 5 on the surface of the suction plate 3 on which the suction holes 1 are formed, and a vacuum pump (not shown) is connected through a hose connected to the suction connection 2. By reducing the pressure to make the inside of the suction plate 3 in a reduced pressure state, the workpiece 4 is suction-fixed on the suction plate 3 to prevent the displacement thereof and to process the work.

[0004] The vacuum suction method has an advantage that a workpiece can be easily fixed and a positional deviation during processing can be prevented. And as the porous sheet 5 of the vacuum suction device,
Porous materials such as ceramic perforated plates and sintered metal plates have been used.

[0005] However, in recent years, the shape of the workpiece has become complicated and the processing shape has become complicated, and it is difficult to obtain a sufficient suction force with a ceramic porous body or a metal sintered plate having a large hole diameter. In some cases, the object may be damaged during suction, such as dents along the hole. Further, in the case where two or more members are joined by bonding or the like, a porous metal plate or a ceramic porous body lacks adhesion during compression. For this reason, a porous resin sheet having a smaller pore diameter has been proposed as the porous sheet 5 (Japanese Unexamined Patent Application Publication No. Hei 8-
No. 169971).

On the other hand, in recent years, the shape of a processing object has become complicated and the processing shape has also become complicated. Therefore, a method of processing by computer control and a method of controlling using an image recognition result by an image recognition apparatus at that time have been developed. Increasing. In addition, when an object to be conveyed is suction-fixed and conveyed, a suction conveyance method for performing conveyance control using an image recognition result or a processing unit for processing the suction-fixed object to a processing position. In addition, a suction processing method for performing position control using an image recognition result for a workpiece is being adopted.

[0007]

In the processing control using the image recognition result as described above, it is necessary to accurately recognize the shape, the part, and the position of each part of the object. It is desirable that the adsorption surface or the like, which is a part, does not affect recognition. However, when a conventional porous resin sheet is used, a suction hole below the porous resin sheet may be seen through the porous resin sheet, and may be erroneously recognized as a mark for positioning an object. In addition, a general porous resin sheet is easily deformed in a concave shape on the suction hole due to its strength and air permeability, and image recognition becomes unstable due to the deformation when the mark is thereon. There is. This is a problem particularly when a sheet or member having no stiffness and low elastic modulus is fixed by suction.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a suction conveyance method and a suction processing method in which image recognition is less likely to be unstable due to the influence of a suction surface and high-precision control can be performed.

[0009]

Means for Solving the Problems The present inventors have made a sintered porous body of ultrahigh molecular weight polyethylene having a thickness of 0.1 to 3 mm.
It has been found that the above object can be achieved by forming an adsorption surface with a porous sheet having a thickness of 2 mm, and the present invention has been completed.

That is, according to the suction transfer method of the present invention, when a transfer object is transferred by moving the suction plate while the transfer object is suction-fixed to the suction surface of the suction plate, the image recognition result for the transfer object is determined. In the suction transfer method for controlling the transfer by utilizing the suction plate, the suction surface of the suction plate is made of a sintered porous body of ultra-high molecular weight polyethylene having a thickness of 0.1 to 3 mm.
mm porous sheet.

On the other hand, according to the suction processing method of the present invention, when the workpiece is suction-fixed to the suction surface of the suction plate and the processing means for processing the workpiece is moved to the processing position, In the suction processing method of performing position control using an image recognition result with respect to the above, the suction surface of the suction plate is formed of a porous sheet having a thickness of 0.1 to 3 mm made of a sintered porous body of ultra-high molecular weight polyethylene. There is a feature.

[0012] Further, another suction processing method of the present invention is directed to the first method.
In a state where the workpiece is suction-fixed to the suction surface of the suction plate, and the workpiece is suction-fixed to the suction surface of the second suction plate,
When transporting the transported object to the processing position for the workpiece by moving the second suction plate, transport control is performed using the image recognition result for the transported object and / or the workpiece. In the adsorption processing method, the adsorption surface of the second adsorption plate and / or the first adsorption plate is formed of a porous sheet having a thickness of 0.1 to 3 mm made of a sintered porous body of ultra-high molecular weight polyethylene. It is characterized by.

According to the suction conveying method or the suction processing method of the present invention, the suction surface on which the object of image recognition is to be suction-fixed has a thickness of 0.1 mm made of a sintered porous body of ultra-high molecular weight polyethylene. Since it is formed of a porous sheet having a thickness of about 3 mm, the suction surface hardly affects image recognition, and the shape, site, position of each part, and the like of the object can be accurately recognized. This is because the fine holes are formed uniformly, and the deformation due to the suction holes is small in relation to the air permeability and the elastic modulus. Also, in the joining process of the sheet-like material, since the adhesiveness of the member is high due to the cushioning property, stable processing is possible, and since it is excellent in abrasion resistance, it has durability against processing and suction, It has low self-dusting properties and can avoid problems of contamination and contamination. Furthermore, even if the target is amorphous or the target is located at any position, the suction force can be reliably fixed without changing the suction force by the uniform fine holes, and the conveyance and processing can be performed. Can be performed with high accuracy.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in the order of a porous sheet, a suction conveyance method, and a suction processing method.

[Porous Sheet] The porous sheet in the present invention is formed from UHMWPE. UHM
WPE is characterized in that the molecular weight (measured by a viscosity method) of general polyethylene is about 100,000 or less, while the molecular weight is about 500,000 or more. Such UHMWPE
For example, from Mitsui Petrochemical Industries, Inc.
Million "and Hoechst AG under the trade name" Hostalen GUR ".

The UHMWPE porous sheet preferably has a coefficient of friction of 0.3 or less, more preferably 0.2 or less. When the friction coefficient exceeds 0.3, the life when used for suction fixing tends to be short.

The thickness, porosity, and pore size of the UHMWPE porous sheet are set to a value of 0.1 to reduce the deformation due to the suction hole because the shape of the hole hardly affects the image recognition.
３3 mm, a porosity of 5-60%, and a pore size of 5-200 μm are preferred, and a thickness of 0.5-2 mm, a porosity of 20-40%, and a pore size of 10-150 μm are more preferred.

Next, an example of a method for producing the UHMWPE porous sheet will be described. In this method, a mold is filled with UHMWPE powder, and then sintered in a steam atmosphere heated to a temperature equal to or higher than the melting point of UHMWPE to form a block-shaped compact, and then cooled. It is to be cut into a sheet.

In this method, first, UHMWPE
Filling a mold with powder (particle size is usually 30-200 μm)
Next, this is sintered in a steam atmosphere heated to the melting point of UHMWPE or higher to obtain a block-shaped molded body. Since the mold is filled with the UHMWPE powder and sintered in a heated steam atmosphere, a mold having at least one opening (for introducing heated steam) is used. The time required for sintering varies depending on the filling amount of the powder, the temperature of steam, and the like, but is usually about 1 to 12 hours.

The steam used at this time is pressurized in order to raise the temperature above the melting point of UHMWPE, so that it can easily enter between the UHMWPE powders filled in the mold. In order to make it easier for heated steam to enter between the UHMWPE powders, the powder was filled in a mold, and the mold was placed in a pressure-resistant container, subjected to a deaeration operation under reduced pressure, and then heated. Sintering may be performed in a steam atmosphere. The degree of pressure reduction at this time is not particularly limited, but is preferably about 1 to 100 mmHg.

Therefore, the sintering of the UHMWPE powder filled in the mold is performed by providing a steam introduction pipe and an opening / closing valve thereof in the pressure-resistant container and degassing the air between the powders.
The method can be carried out by a method of opening the steam valve and introducing heated steam while stopping or continuing to reduce the pressure.

During the sintering, the UHMWPE powder is heated to a temperature not lower than its melting point, but does not flow much because of its high melt viscosity, and maintains a part or most of the powder shape, and the adjacent powders have the same shape. Heat fusion is performed at the contact portion to form a porous block-shaped molded product (the non-contact portions between the powders become micropores of the porous molded product). During sintering, pressure may be applied as desired, but the pressure is usually preferably about 10 kg / cm ² or less.

After sintering as described above, it is cooled. During cooling, it is preferable to avoid rapid cooling in order to prevent cracks from forming in the block-shaped molded body. For example, a method in which the molded body is left at room temperature and cooled can be employed. The cooling may be performed while the block-shaped molded body is placed in the mold, or may be removed from the mold. After cooling the block-shaped molded body in this manner, a porous sheet can be obtained by cutting to a predetermined thickness with a lathe or the like.

The pore size and porosity of the micropores of the porous sheet obtained by the above method are determined by the particle size of the UHMWPE powder to be used and the presence or absence of pressure during sintering. If the other conditions are the same, the larger the particle size of the powder used, the larger the pore size of the fine pores, and a porous sheet having a high porosity can be obtained. In addition, when pressure is not applied during sintering, a porous sheet having a large pore diameter and a high porosity can be obtained as compared with the case where pressure is applied. Furthermore, when pressure is applied during sintering, the higher the pressure, the smaller the pore size of the micropores and the lower the porosity of the porous sheet.

UHMWP obtained by such a method
E porous sheet, as described above, the adjacent UHMWP
E has a microstructure in which the powder maintains a part or a large part of its shape, and the powders are heat-sealed at their contact portions to form a sheet, and the non-contact portions of the powders have micropores. ing. The microstructure of this porous sheet is
For example, the porous sheet can be cut along the thickness direction, and the cut surface can be observed using a scanning electron microscope (the magnification is appropriately set, but is usually about 100 to 1000 times).

The porous sheet according to the present invention may have been subjected to an antistatic treatment. By performing the antistatic treatment, for example, a spark due to charging of the porous sheet can be avoided in a dicing process of a semiconductor wafer, and damage to the wafer due to the spark can be prevented. Further, it is possible to prevent dust and dirt from adhering to a workpiece such as a semiconductor wafer.

The antistatic treatment on the porous sheet does not need to be exceptional, and a usual method can be employed. For example, when producing a porous sheet by the above method, UHMWP
Prior to filling the E powder into a mold, the powder and the antistatic agent may be mixed, and the mixture may be used for the operation. In addition, the porous block-shaped molded body or the porous sheet obtained by cutting the same is brought into contact with the antistatic agent-containing liquid (immersion, coating, etc.),
A method of impregnating the molded article or sheet with an antistatic agent can also be employed. The amount of the antistatic agent used when performing this treatment is not particularly limited, but usually the proportion of the antistatic agent in the weight of the treated porous sheet is 0.5 to
It is in the range of 2% by weight.

As the above-mentioned antistatic agent, "Elecnon OR"
Commercially available products such as "W (manufactured by New Fine Chemical Co., Ltd.)" and "Electro Stripper (manufactured by Kao Corporation)" can be used, and inorganic conductive materials such as carbon black powder and metal powder can be used.

The porous sheet according to the present invention may be colored. Although the UHMWPE porous sheet is white and opaque, when it is colored in any color, there are the following advantages, for example. When the UHMWPE porous sheet is used for cutting a glass plate for liquid crystal, scribing marks (thin lines close to white) are formed on the glass plate in the scribing step. However, when the porous sheet is white, the porous sheet below the glass plate is removed. In some cases, it is difficult to distinguish between the sheet and the scribe mark by image recognition, and it may be impossible to perform processing control in the subsequent cutting processing. However, if the UHMWPE porous sheet is colored in an arbitrary color other than white, the scribe mark can be easily recognized as an image by the contrast between the white color of the scribe mark and the color of the porous sheet so that the cutting process can be performed with high accuracy. become. In order to obtain the colored porous sheet by the above-described method, for example, prior to filling the UHMWPE powder into a mold, the powder and the pigment may be mixed, and the mixture may be used for the operation.

The method of forming the porous sheet according to the present invention as the suction surface of the suction plate described below is performed by partially (streak-like, dot-like) the formation surface of the suction surface using, for example, a double-sided adhesive tape or an adhesive layer. (Mesh-like or the like) or a method of detachably fixing the vicinity of the edge with a stopper or the like. In addition, as the adhesive, the workability of bonding to the base,
A pressure-sensitive adhesive is preferable in consideration of the ease of peeling from the base when the sheet is replaced, but a hot-melt adhesive or a thermosetting adhesive can also be used.

[Suction and Conveyance Method] The suction and conveyance method of the present invention is a method for carrying an object by moving the suction plate while the object to be conveyed is suction-fixed to the suction surface of the suction plate.
The transport control is performed using the image recognition result for the transported object. Since the suction conveyance method itself is publicly known, a detailed description based on the drawing of the apparatus is omitted, but the following is exemplified as a suction plate moving mechanism, an image recognition device, a control method, and the like.

As the moving mechanism of the suction plate, an XY table provided with various driving mechanisms, an XYZ table, a table having a rotational degree of freedom, a table such as a stage, a robot hand, a conveyor, etc. are constituted by the suction plate. Is mentioned.

Examples of the image recognition device include a CCD camera, an ITV, an infrared camera, and an image sensor having image processing means. These may be arranged toward the conveyance end position or may be arranged in the middle of the conveyance and used for measuring the relative positional relationship between the suction plate and the object to be conveyed.

The result of the image recognition is taken into a control flow as data for specifying the shape, part, and position of each part of the object, and is used for transport control.

For example, as shown in FIG. 1, the suction plate is provided with a predetermined number of suction holes 1 on the upper surface and a suction connection portion 2 at a predetermined position (a material having mechanical strength such as metal). 3), and the above-described porous sheet 5 is fixed on the surface on which the suction holes 1 are formed. The workpiece 4 is placed on the porous sheet 5,
The workpiece 4 is suction-fixed onto the suction plate 3 by depressurizing the inside of the suction plate 3 through a hose connected to the suction connection part 2 to reduce the pressure inside the suction plate 3, thereby displacing the position thereof. Can be performed while preventing suction.

In the case of transportation including vertical movement by a robot hand or the like, suction and fixing from above may be performed, in which case the drawing is turned upside down. In addition, it is also possible to fix by suction from the horizontal direction.

[Suction Processing Method] In the suction processing method of the present invention, when a workpiece is suction-fixed to the suction surface of a suction plate and the processing means for processing the workpiece is moved to a processing position, The position control is performed using the image recognition result for the workpiece. Since this adsorption processing method itself is publicly known, detailed description based on the apparatus drawings is omitted, but processing means, a moving mechanism of the processing means, an image recognition device,
The following are examples of the control method and the like.

As processing means, joining (including bonding, bonding, welding, etc.) of members, cutting, coating, marking, polishing, grinding, drilling, dry etching, vapor deposition, and processing of a workpiece are performed. Any means for mounting, fixing, and the like the above components may be used.

Examples of the moving mechanism of the processing means include an XY table, an XYZ table provided with various driving mechanisms, a table and a stage having a further degree of freedom of rotation, a robot hand, and the like.

Examples of the image recognition device include a CCD camera, an ITV, an infrared camera, and an image sensor having an image processing means. These are arranged towards the workpiece on the suction surface. The result of image recognition is the shape of the object,
The data is specified in a control flow as data for specifying a part, a position of each part, and the like, and is used for position control when the processing means is moved to the processing position.

The suction plate itself is the same as in the suction transport method described above. The suction plate on which the workpiece is fixed by suction may be transportable by a transport mechanism.
In that case, the above-mentioned suction conveyance method may be adopted.

[Another Suction Processing Method] In another suction processing method of the present invention, a workpiece is suction-fixed on a suction surface of a first suction plate, and a workpiece is suction-fixed on a suction surface of a second suction plate. In this state, when the transported object is transported to the processing position for the workpiece by moving the second suction plate, the image recognition result for the transported object and / or the workpiece is used. This is to control the transport. Since this suction processing method itself is publicly known, a detailed description based on the device drawing is omitted, but the following are the second suction plate moving mechanism, processing means, processing means moving mechanism, image recognition device, control method, and the like. Are exemplified.

As a moving mechanism of the second suction plate, an XY table provided with various driving mechanisms, an XYZ table,
A table, a stage, a robot hand, and the like further having a rotational degree of freedom are exemplified.

The image recognition device includes a CCD camera, an ITV, an infrared camera, and an image sensor having an image processing means. When using the image recognition results for the transported object, these are not only placed toward the transport end position, but also placed in the middle of transport to measure the relative positional relationship between the suction plate and the transported object, etc. May be used. When the image recognition results for the workpiece are used, they are arranged toward the workpiece on the suction surface.

The result of the image recognition is taken into a control flow as data for specifying the shape and the part of the object to be conveyed and / or the position of each part, and is used for the conveyance control.

As a processing method using an object to be conveyed, any method of joining (including bonding, bonding, welding, etc.) members, mounting and fixing components and the like may be used.

The first and second suction plates themselves are the same as in the case of the suction and conveyance method described above. Further, the first suction plate on which the workpiece is suction-fixed may be conveyable by a conveyance mechanism, and in that case, the above-described suction conveyance method may be employed.

In the present invention, at least one of the suction surfaces of the second suction plate and / or the first suction plate for performing the image recognition device is formed of the above-described porous sheet.

[0049]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and the like specifically showing the configuration and effects of the present invention will be described below.

Example 1 An adsorption plate shown in FIG. 1 was formed of a sintered porous body of ultra-high molecular weight polyethylene having a thickness of 0.5 mm and a porosity of 35%.
A porous sheet having a pore size of 50 μm was attached, and suction was performed with a suction blower that could be adjusted to maintain a constant suction force. Next, an irregular-shaped circuit board was installed, and it was confirmed whether the circuit board was fixed. Further, a circuit board from which another circuit board was suction-fixed to the same suction plate was automatically conveyed from above, and positioning was performed by image recognition with a CCD camera in order to join the two types of boards, and as a result, both were accurately positioned. We were able to join. Further, the bonded circuit board could be sucked from above and transported to the next step.

COMPARATIVE EXAMPLE 1 The porous sheet of Example 1 was replaced with a suction plate SP made of SMC.
Except for replacing the porous sheet of the series (SUS material sintered metal, pore diameter φ0.3 mm, opening ratio 15% or more, porosity 30%, surface lapping finish), two kinds of substrates were prepared in the same manner as in Example 1. Attempts were made to join, but there were long holes with unequal hole diameters, and erroneous recognition occurred when reading images, making positioning control impossible.

Comparative Example 2 The porous sheet of Example 1 was replaced with a ceramic porous sheet (particle size: 46, porosity: 35%, average pore diameter: 0.22 m).
An attempt was made to bond two types of substrates in the same manner as in Example 1 except that m) was replaced. At that time, the image reading became possible although the image was rough, but dust was deposited in black during use, and the image reading became unstable. Further, there is a problem that it is difficult to clean the porous sheet and it is too expensive to replace the porous sheet.

Comparative Example 3 Two types of substrates were joined in the same manner as in Example 1 except that the porous sheet of Example 1 was replaced with an aluminum suction plate (hole diameter φ1.2 mm, interval 6 mm). However, the image could not be read without avoiding the holes.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a suction plate according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Suction hole 2 Suction connection part 3 Suction plate 4 Workpiece (or workpiece) 5 Porous sheet

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/68 H01L 21/68 BF 21/301 21/78 N (72) Inventor Keigo Funakoshi Osaka 1-1-2 Shimohozumi, Ibaraki-shi Nitto Seiki Co., Ltd. F-term (reference) 3C007 DS01 FS01 FT00 FT11 FU00 3C016 CE05 DA05 HC02 3F061 AA01 CA01 CB00 CB05 CC00 3F101 CB08 LA15 LB10 LB12 5F031 CA02 CA05 FA01 FA02 FA07 GA24 GA25 GA26 HA02 HA03 HA10 HA13 HA53 JA04 JA27 KA06 KA07 KA08 MA34 PA21

Claims (3)

[Claims] 1. A suction device for performing conveyance control by using an image recognition result for an object to be conveyed when the object to be conveyed is conveyed by moving the suction plate while the object to be conveyed is suction-fixed to an adsorption surface of the adsorption plate. In the transfer method, the suction surface of the suction plate is formed of a porous sheet having a thickness of 0.1 to 3 mm and made of a sintered porous body of ultra-high molecular weight polyethylene. 2. A workpiece is suction-fixed to a suction surface of a suction plate, and when a processing means for processing the workpiece is moved to a processing position, an image recognition result for the workpiece is used. In an adsorption processing method for performing position control, an adsorption surface of the adsorption plate is formed of a porous sheet having a thickness of 0.1 to 3 mm made of a sintered porous body of ultra-high molecular weight polyethylene. Method. 3. The workpiece is suction-fixed to the suction surface of the first suction plate, and the workpiece is suction-fixed to the suction surface of the second suction plate. In the suction processing method of performing transfer control using an image recognition result for the transferred object and / or the processed object when the transferred object is transferred to a processing position for the object, the second suction plate and / Or the first
An adsorption processing method, characterized in that the adsorption surface of the adsorption plate is formed of a porous sheet having a thickness of 0.1 to 3 mm made of a sintered porous body of ultra-high molecular weight polyethylene.