JP4626885B2 - Dust processing device for roller conveyor - Google Patents

Description

The present invention is a configuration in which an object to be transported such as a cassette for storing a semiconductor substrate is transported by a roller conveyor, and particularly in a clean room where the surrounding environment needs to be maintained in a dust-free state, The present invention relates to a dust processing apparatus in a roller-type conveyor for preventing dust generated by contact between an object to be conveyed and a roller-type conveyor roller that rolls in contact with the object to be conveyed.

For example, in a semiconductor manufacturing factory, a cassette containing a large number of semiconductor substrates is transported by a roller-type conveyor laid in a clean room, and transported to a place where cleaning, CVD, and other treatments are performed.
By the way, the cassette conveyed by a roller type conveyor contacts the bottom part, and is conveyed by the roller for rolling conveyors. At this time, the contact surface between the bottom surface of the cassette and the roller in contact with the roller undergoes rolling friction, and as a result, generation of dust cannot be avoided.

As described above, Patent Document 1 below discloses a prior art that accurately captures and captures dust generated on the contact surface between the bottom surface of the cassette and the rollers of the roller-type conveyor that conveys the cassette before it is scattered around. There is.
The technique disclosed in Patent Document 1 is a roller-type conveyor provided with a series of rollers driven at a synchronous speed, and a transport container (see reference numeral 103 in FIG. 2) transferred on the roller-type conveyor. A cleaning roller 5 in which foreign matter (dust) generated by rolling or sliding friction between the bottom surface and the roller facing the roller is arranged at appropriate intervals in a series of aluminum rollers 3 is disposed. In this technique, the foreign matter is taken in.

Thus, the foreign matter taken in by the cleaning roller 5 is peeled off from the surface of the cleaning roller 5 by the brush 6 as disclosed in FIG.
On the other hand, instead of the cleaning roller, a disposable adhesive tape having slight adhesiveness on the surface of a normal roller is laminated and wound so that the adhesive surface is on the outer side, and the degree of contamination due to adhesion of foreign matter is reduced. Remove the adhesive tape foreign material layer (approx. The length corresponding to one round of the roller) at an appropriate time to reach a certain limit, and remove the foreign material on the surface of the cleaning roller contact surface (transport container, cassette, etc.) There is also disclosed a method for obtaining a state where there is no (see the description [0026] column)

JP-A-11-236117

When a transported object such as a semiconductor substrate storage cassette is transported in a clean room by rotating a series of rollers in a roller conveyor, the roller and the transported object are transferred when the transported object is transferred along with the rotation of the roller. The generation of dust due to friction is inevitable unless the conveying speed is extremely low.
However, from the viewpoint of improving the conveyance efficiency of the object to be conveyed, the conveyance speed of the roller conveyor is increased and the generation of the dust is inevitable.
The dust that is inevitably generated along with the conveyance of the roller conveyor causes a decrease in yield particularly in the semiconductor product manufacturing process, and therefore it is necessary to prevent dust from being scattered to the surroundings.

As a prior art for realizing this, there is Patent Document 1 mentioned above.
However, this prior art has a configuration in which the surface of the roller in which dust generated with a change in the contact portion between the roller of the roller conveyor and the object to be conveyed is arranged at a predetermined appropriate interval has a slight adhesiveness. . Then, scrape the dust adhering to the roller surface with a brush, or peel off the dust-adhered layer (generally equivalent to one round layer) of the adhesive tape laminated and wound around the roller according to the degree of dust adhesion. I am doing so.

Such a prior art according to Patent Document 1 captures dust generated with fluctuations in the contact portion between a roller of a roller-type conveyor and an object to be conveyed and prevents a situation in which the dust is discharged to the surroundings. Although it is possible to accurately capture the dust adhering to the object side, it is not possible to accurately capture the dust adhering to the roller having no adhesiveness on the surface.
In addition, the means for winding the adhesive tape around rollers at appropriate intervals and peeling off the adhesive tape corresponding to one rotation layer on the surface according to the adhesion of the surrounding dust is to peel off the adhesive tape several times. Accordingly, the outer diameter of the roller provided with the adhesive tape gradually decreases.
Along with this, the outer diameter of the roller wound with the adhesive tape gradually decreases in diameter, and in order to align with the surface level of the adjacent roller, the vertical direction of the support shaft of the roller wound with the adhesive tape Therefore, there is a tendency to make the configuration complicated.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to remove dust adhering to a surface to be conveyed traveling on a series of rollers, for example, a surface of a cassette for housing a semiconductor substrate, with the rotation of the series of rollers in a roller type conveyor. By means of removing continuously or at appropriate time intervals, it is possible to capture efficiently without requiring a complicated mechanism, and at the same time, dust adhering to all rollers along the traveling path of the conveyed object is scattered around. An object of the present invention is to provide a dust processing apparatus in a roller type conveyor that can be captured without any trouble.

Means and effects for solving the problems

In order to solve the above-mentioned problem, the dust processing apparatus in the roller type conveyor according to claim 1, wherein the objects to be conveyed are arranged continuously along a predetermined path and on a series of rollers which are subjected to rotation control at a predetermined speed. A dust processing device used in a roller type conveyor for transporting in a dust , which is provided on a bottom surface portion of the object to be transported and comes into contact with the roller, and the contact portion changes due to rolling or friction. and adhesive material adhering the is characterized by having a brush roller interposed, to remove the deposited dust to the adhesive material in said series of rollers at predetermined intervals.

According to the present invention, in particular, in a roller type conveyor installed in a place (clean room or the like) where the surrounding environment needs to be kept in a clean state, a series of rollers and an object (container for housing a semiconductor substrate, etc.) It is possible to take in dust generated by rolling friction at the contact portion with the object to be conveyed.
Therefore, dust generated at the part of each roller that contacts the object to be conveyed is captured on the object to be conveyed side without being scattered around, and the captured dust is accurately removed continuously or at appropriate time intervals. can do.
The dust removing brush roller can eliminate dust adhering to the opposing contact surface of the roller of the conveyed object.
According to a second aspect of the present invention, in the dust treatment apparatus for the roller type conveyor according to the first aspect, the brush roller is rotationally controlled at a rotational speed different from the series of rollers or in a reverse direction. This is more preferable.
Further, as in the invention described in claim 3, the dust processing device in the roller type conveyor according to claim 1 or 2, further comprising a dust collecting air intake device for sucking the dust removed by the brush roller. By doing so, it is possible to accurately prevent the excluded dust from scattering to the surroundings, which is more preferable.
Furthermore, as in the invention according to claim 4, in the dust treatment apparatus for a roller conveyor according to any one of claims 1 to 3, the adhesive property is applied only to a part of the object to be transported that plays a role of cleaning. It is more preferable if a material is provided.

The dust processing apparatus in the roller type conveyor according to claim 5 is the dust processing apparatus in the roller type conveyor according to any one of claims 1 to 4, wherein the object to be transported is stored in a clean room. It is a cassette.
According to the present invention, the effects of the inventions according to the first to fourth aspects of the present invention are not limited to the above, but dust scattering generated in the process of transporting the cassette for housing a semiconductor substrate in a semiconductor manufacturing apparatus that needs to maintain a particularly clean environment. Can be accurately prevented without complicating the configuration.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
First, the outline of the drawing will be described. FIG. 1 is a front view showing the relationship between a roller type conveyor to which the present invention is applied and an object to be conveyed, and FIG. 2 is a diagram showing a driving roller group of the roller type conveyor. FIG. 3 is a perspective view showing an exaggerated view of the main part of the bottom part of the conveyed object.

The most preferred embodiment of the present invention is shown in FIGS. In FIG. 1, 1 is a roller type conveyor (the drive source is omitted). Reference numerals 2 and 3 denote roller support members, which are laid in parallel along the path of the roller conveyor 1 while maintaining equal intervals. Reference numerals 4 and 5 denote support shafts, which are continuously arranged at regular intervals along the roller support members 2 and 3, respectively, and are fixed to the roller support members 2 and 3. 6 and 7 are rollers, each having cylindrical holding portions 6a and 7a for supporting both side portions of the bottom surface of the object to be described later, and flanges 6b and 7b for regulating the position of the object to be conveyed in the left-right direction, The roller support members 2 and 3 are rotatably supported by the roller support members 2 and 3, respectively.

And, on each peripheral surface of the cylindrical holding portions 6a, 7a, urethane rubber coating portions 6ax, 7ax are coated to increase the contact friction force with the object to be conveyed, and in the process of conveying the object to be conveyed, It prevents slipping between the conveyed object and the cylindrical holding portions 6a and 7a of the rollers 6 and 7.
Reference numeral 8 denotes an object to be conveyed. As a most preferable application example, there is a cassette containing a semiconductor substrate which is transferred in a clean room and sequentially subjected to various kinds of processing (chemical processing such as cleaning and CVD).
The rollers 6 and 7 are provided with driving means only on one side (roller 6 in this example), and the other (roller 7 in this example) is rotatably supported by the support shaft 5 and does not have driving means. It is a driven roller.

Incidentally, the driving means for the five rollers 6 constituting one block is configured as shown in FIG. 2, and a plurality of blocks are continuously arranged in the entire roller conveyor 1.
First, in FIG. 2, the roller 6 rotatably supported by the support shaft 4 laid on the roller support member 2 of the roller type conveyor 1 is opposite to the flange portion 6b of the cylindrical holding portion 6a. A toothed pulley 6c is provided. A toothed pulley 9b is fixed to a drive shaft 9a of the motor 9, and the toothed pulley 9b is disposed on the same vertical plane as the toothed pulley 6c fixed to the series of rollers 6.

Reference numeral 10 denotes a timing belt for a plurality of (5 in the example shown in FIG. 2) toothed pulleys 6c provided on the toothed pulley 9b serving as a driving source of the roller 6 and a series of rollers 6 arranged in a straight line. The tooth portion 10a side (inner peripheral surface) is sequentially engaged to form one loop. And the tension roller 11 is arrange | positioned in the suitable place (2 places in the example shown in FIG. 2) of the side (outer peripheral surface) which does not have the tooth | gear part 10a of the said timing belt 10. FIG.
The support shaft 11a of the tension roller 11 is supported by known means (not shown) that can move so as to have a restoring force in the direction in which the timing belt 10 is tensioned.

Next, a configuration that is a main part of the present invention and has the characteristics of the conveyed object 8 will be described with reference to FIGS. 1 and 3. 1 and 3, reference numerals 12 and 13 denote adhesive tape laminates, which are provided along the portions including the portions of the cylindrical holding portions 6a and 7a of the rollers 6 and 7 that are in contact with the urethane rubber covering portions 6ax and 7ax, respectively. It is done.
At this time, the adhesive tape laminates 12 and 13 are formed by laminating a large number (for example, 40) of adhesive tapes having a thickness of about 0.07 mm (similar to conductive adhesive mats used at the entrance of a clean room), and the urethane rubber. A slight adhesive material is applied to the surface in contact with the covering portions 6ax and 7ax.
And this adhesive tape laminated body 12 and 13 is adhesively fixed to the bottom face both sides of the to-be-conveyed object 8, for example with the double-sided adhesive tape which is not shown in figure.

Next, the operation of the above configuration will be described as follows.
First, when each motor 9 in a plurality of blocks of the roller conveyor 1 is driven, the toothed pulley 9b rotates in FIG. 2 showing one of the blocks, and accordingly, the toothed pulley 9b meshes with the toothed pulley 9b. The timing belt 10 that forms two loops receives power to perform circulation driving.
At this time, the toothed pulley 6c that engages with the tooth portion 10a of the timing belt 10 rotates. Thereby, each roller 6 rotates synchronously.
The timing belt 10 is always given a substantially constant level of tension by the tension roller 11, and the toothed pulley 6 c on the roller 6 side and the toothed pulley 9 b on the motor 9 side are engaged with the tooth portion 10 a of the tension belt 10. Is maintained properly.

Next, means for forming the gist of the present invention, that is, dust processing generated when the object 8 is conveyed by the rollers 6 and 7 will be described.
First, the peripheral surfaces of the cylindrical holding portions 6a and 7a of the rollers 6 and 7 were respectively coated on the adhesive surfaces of the adhesive tape laminates 12 and 13 adhered to the bottom surface of the article 8 to be conveyed. The urethane rubber covering portions 6ax and 7ax are in contact with each other, and the conveyed object 8 is transferred by the driving force of the roller 6.
In transferring the object to be conveyed 8 on the roller conveyor 1, the driving force is exclusively received from the roller 6 and the roller 7 is only driven, and the transfer direction of the object to be conveyed 8 becomes unstable. Is accurately compensated by the action of restricting the transfer direction of the conveyed object 8 of the flanges 6b, 7b of the rollers 6, 7.

In the process of transferring the object 8 to be conveyed on the roller conveyor 1 laid in the clean room in this way, the urethane rubber coverings 6ax on the peripheral surfaces of the cylindrical holding portions 6a and 7a of the rollers 6 and 7, When 7ax rolls on the lower surface of the outermost layer of the pressure-sensitive adhesive tape laminates 12 and 13 bonded to the article 8 to be conveyed, dust is generated based on the rolling friction of the contact surface.
This dust adheres to the adhesive surface of the adhesive tape, does not scatter around the clean room, and does not cause environmental pollution of the clean room.

As dust adhering to the adhesive surface on the bottom surface of the outermost layer of the adhesive tape laminates 12 and 13 gradually increases, the dust trapping force of the adhesive surface decreases, and there is a possibility that part of the dust will scatter around. .
Therefore, the lowermost layer of the pressure-sensitive adhesive tape laminates 12 and 13 is peeled off before exceeding the limit at which dust can be accurately captured on the pressure-sensitive adhesive surface. Thereby, the adhesiveness of the adhesive surface of the new tape exposed in the outermost layer of the adhesive tape laminates 12 and 13 returns to the initial state.
The thickness of the pressure-sensitive adhesive tapes constituting the pressure-sensitive adhesive tape laminates 12 and 13 is very small in principle by peeling the pressure-sensitive adhesive tapes one by one from the bottom layer of the pressure-sensitive adhesive tape laminates 12 and 13 one by one. Even if the thicknesses of the tape laminates 12 and 13 are sequentially reduced, there is no practical problem.

By the way, in the structure of FIGS. 1-3, the rollers 6 and 7 of the roller conveyor 1 and the adhesive tape laminated bodies 12 and 13 for dust trapping of the to-be-conveyed object 8 corresponding to these contact, and the rollers 6 and 7 are contacted. The conveyed object 8 is transferred by the rolling.
At this time, the driving force required by the roller 6 increases as the degree of adhesion between the rollers 6 and 7 and the adhesive surfaces of the adhesive tape laminates 12 and 13 in contact with the rollers 6 and 7 increases.
On the other hand, when the adhesive surface of the adhesive tape laminates 12 and 13 captures dust and the adhesiveness of the adhesive surface decreases, the dust attached to the rollers 6 and 7 cannot be accurately captured and scattered around, A clean environment cannot be maintained.

Therefore, it is necessary to set the adhesiveness of the adhesive surfaces of the adhesive tape laminates 12 and 13 to a predetermined appropriate value.
However, the adhesive tape laminates 12 and 13 have many opportunities to select and use commercially available products. In such a case, it is difficult to adjust the adhesiveness of the adhesive surface and it is difficult to obtain a desired adhesiveness.
As a means for this, the adhesive tape laminates 12 and 13 are respectively divided (specifically, divided into two along the transported direction), and the adhesive tape is placed before and after the transported object 8 in the transport direction as shown in FIG. The laminated bodies 12a, 12b, 13a, and 13b are bonded in accordance with the adhesive tape laminated bodies 12 and 13.
As a result, the driving force that compensates for the contact resistance between the pressure-sensitive adhesive tape laminate and the rollers 6 and 7 (the driving force that does not contribute to the conveyance of the article 8 to be conveyed) can be suppressed.

FIG. 5 is a side view schematically showing the main part of the embodiment of the present invention. Reference numeral 21 denotes a roller conveyor, which is composed of a series of rollers 21a that are rotated synchronously by a driving means (not shown). A brush roller 22 is interposed in the series of rollers 21a at an appropriate interval. Reference numeral 23 denotes an object to be transported such as a cassette for housing a semiconductor substrate, which is regulated by the series of rollers 21a in a direction along the laying path and is transferred by the rotation of the rollers 21a.

The brush roller 22 has the same surface height as the series of rollers 21a, and is subjected to rotation control at a different rotational speed or reverse rotation from the series of rollers 21a. Reference numeral 24 denotes a slightly adhesive material, which is provided at the bottom of the first-stage transported object 23 where at least a series of rollers 21a come into contact. Reference numeral 25 denotes a dust collecting air intake device, which is provided with an opening 25a in the lower part of the brush roller 22, and is configured to take in the dust discharged to the opening 25a based on the air suction action from the air intake port 25b.

In the configuration shown in FIG. 5, in the process in which the object to be conveyed 23 is transferred along with the rotation of the roller 21 a of the roller type conveyor 21, the fine adhesive material 24 provided on the bottom of the object to be conveyed 23 facing the roller 21 a The dust generated by the change in the contact portion between the fine adhesive material 24 and the roller 21a is captured.
Next, the dust trapped in the fine adhesive material 24 is the difference between the rotational peripheral speed of the brush roller 22 and the transport speed of the transported object 23 while the transported object 23 is transported on the brush roller 22. At a speed, the brush roller 22 scrapes off dust trapped in the fine adhesive material 24.
Thus, the dust scraped off from the surface of the fine adhesive material 24 is captured by the dust collecting intake device 25.

The roller type conveyor of FIG. 1 is composed of a pair of separated drive rollers and driven rollers. However, the roller type conveyor is not the separation roller, but extends the drive roller to the position of the driven roller as one drive roller. It is also possible to configure.

The adhesive tape laminate adhered to the bottom surface of the object to be conveyed in FIGS. 3 and 4 does not necessarily have to adhere to the bottom surface of all the objects to be conveyed. It is also possible to adhere only to the part.

It is a front view which shows the relationship between the roller type conveyor to which this invention is applied, and the to-be-conveyed object conveyed by this. It is a block diagram which shows the unit block of the drive roller group of a roller-type conveyor. It is a perspective view which exaggerates and shows the principal part in the bottom face part of a to-be-conveyed object. It is a perspective view of the other Example which exaggerates and shows the principal part in the bottom face part of a to-be-conveyed object. It is a side view which simplifies and shows the principal part of the Example of this invention.

Explanation of symbols

1... Roller type conveyors 6 and 7... Rollers 6 c and 9 b... Toothed pulleys 8 and 23.
9 .... Motor 10 ... Timing belts 12, 13, 12a, 12b, 13a, 13b .... Adhesive tape laminate 22 ... Brush roller 24 ... Fine Adhesive 25 ... Dust collector

Claims (5)

A dust processing apparatus used in a roller-type conveyor for transferring a transported object on a series of rollers that are continuously arranged along a predetermined path and subjected to rotation control at a predetermined speed ,
An adhesive material that is provided on the bottom surface of the object to be conveyed, contacts the roller, and adheres dust generated when the contact portion changes due to rolling or friction; and
A brush roller that is interposed in the series of rollers at a predetermined interval and removes dust adhering to the adhesive material;
The dust processing apparatus in the roller type conveyor which has. The dust treatment apparatus for a roller type conveyor according to claim 1, wherein the brush roller is rotationally controlled at a rotational speed different from that of the series of rollers or in a reverse direction. The dust treatment apparatus for a roller conveyor according to claim 1 or 2, further comprising a dust collection air suction device for sucking dust removed by the brush roller. The dust processing apparatus for a roller type conveyor according to any one of claims 1 to 3, wherein the adhesive material is provided only on a part of the object to be transported that plays a role of cleaning. 5. The dust processing apparatus for a roller conveyor according to claim 1, wherein the object to be conveyed is a cassette for housing a semiconductor substrate that is transferred in a clean room.

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