JP3779708B2 - Manufacturing method of dry barrel polishing container - Google Patents

Description

  The present invention relates to a method for manufacturing a dry barrel polishing container.

  A barrel tank used in a barrel polishing apparatus of a type in which the barrel tank rotates includes a container and a lid that closes the opening of the container. This container is generally composed of a steel housing and an inner wall with a lining made of an elastic material. The lining plays a role in reducing the collision between the grinding stone and the workpiece during polishing and preventing the steel wall from being worn. I am doing. Similarly, the lid side is made of steel and the container closing surface side is lining. Such a barrel tank is mounted on a barrel polishing apparatus to perform a desired polishing process.

  By the way, the steel casing of the container is manufactured by bending a steel plate 39 as shown in FIGS. For example, in order to manufacture a container 47 having a hexagonal cross section having an opening 40 on one side as shown in FIG. 3, the steel plate 39 is bent so as to have a hexagonal cross section, and then both ends are hexagonal steel. The case 42 is closed by welding or the like with the plate 42. Next, the cores 44 a and 44 b are inserted into the housing 41 from the opening 40 and assembled inside to form an integral core 44, and the bridge 31 is bridged over the flange 45 of the housing 41, The core 44 is suspended. Thereafter, a base material for the lining 46 such as a molten polyurethane resin is cast between the inner wall of the housing 41 and the core 44. When this is cooled and solidified, a barrel polishing container 47 having a lining 46 made of polyurethane is formed.

By the way, recently, in the field of barrel polishing, the demand for a dry polishing method that does not use water is increasing from the conventional wet polishing method that uses water from the viewpoint of environmental improvement and processing cost saving. The barrel tank used for dry polishing includes, for example, an external air suction part that introduces air into the wall surface of a container or a lid and a dust discharge part that discharges polishing debris and dust, as disclosed in Patent Document 1 below. When such a barrel tank is attached to the polishing apparatus and started, the polishing stone and the workpiece move relatively fast in the barrel tank, and the workpiece is polished. During polishing, air is taken in from the outside air suction part due to the action of the dust collector, passes through the grinding stone and workpiece and cools them, and polishing dust and dust generated by polishing pass through the dust discharge part to the dust collector side. This is designed to prevent clogging of polishing stones due to polishing debris and dust, which is a problem inherent to dry polishing, and to prevent dirt from adhering to the workpiece.
Japanese Patent No. 2643103

  In order to manufacture such a barrel barrel for dry polishing, after manufacturing the steel casing 41 in the same manner as described above, a lining 46 such as polyurethane is attached by casting, and then a polishing stone is used as an outside air suction part or dust discharge part. A plurality of small holes 50 through which a workpiece cannot pass is formed by drilling (FIG. 4a), or a large ventilation portion 51 is formed in the casing 41, and a lining 46 having a ventilation portion 52 slightly larger than this is formed. A polyurethane piece 5 having a small hole 4 through which a polishing stone or a work cannot pass is fitted to the ventilation portion 52 by bolting or the like and then formed by fitting with a casting mold (FIG. 4b). When a dry polishing barrel is manufactured by the above method, first, the former must be drilled through the steel casing 41 and the lining 46 at the same time. Drilling is very difficult. Because polyurethane is an elastic body, if a small drilling process is performed, it is blocked as soon as the drilling tool is removed. Even if the hole is formed, the end face of the small hole 50 on the inner wall of the barrel tank is deteriorated due to the processing, so that the degree of wear during polishing is severe, and the periphery of the small hole 50 is unevenly worn. If the lining 46 needs to be replaced due to this uneven wear, the entire lining must be replaced, which is wasteful.

  Next, in the latter case, after the steel plate having the ventilation portion 51 is bent to manufacture the steel casing 41, the lining material does not flow into the ventilation portion 51, and the same ventilation portion is also applied to the lining 46 after the lining is completed. A dummy mold is fitted into the ventilation portions 51 and 52 so that the lining material is cast so that 52 is formed. After the lining is solidified, the dummy mold is removed, and a polyurethane piece 5 having a small hole 4 through which a polishing stone or a work cannot pass is bolted to the ventilation portion 52. However, there is a limit to the bending accuracy of the steel casing 41, and distortion due to springback or the like may occur after processing (FIG. 5). Therefore, when the surroundings of the ventilation parts 51 and 52 after completion of the lining are viewed, one of the ventilation parts 51 is displaced from the original position, resulting in a difference in the lining thickness, and when the polyurethane piece 5 with small holes 4 is bolted thereto, the piece 5 And a lining thickness of the ventilation portion 52 are stepped. A step is not preferable because it causes the above-mentioned uneven wear. In particular, when the lid is pressed and closed, a force is applied from above the casing 41, so that the degree of distortion becomes significant, and the gap becomes large or severe when it is severe, which is not preferable.

  In dry barrel polishing, the polishing stone and the workpiece flow in the barrel tank at high speed and repeatedly collide with the lining wall. Therefore, if the workpiece is soft, a dent may occur. In the case of conventional wet polishing, water becomes a buffering agent, so that is not so much. For this reason, the barrel tank for wet polishing can be used without problems even if it uses a high hardness from the viewpoint of wear resistance, but when using a barrel with the same hardness for dry barrel polishing, A problem will occur.

  This invention is completed based on the above situations, Comprising: It aims at providing the manufacturing method of the container of the barrel tank which is hard to produce a dent in a workpiece | work.

As a means for achieving the above object, the invention of claim 1 is a method of manufacturing a dry barrel polishing container having an air circulation part formed on the side surface, which can be opened and closed. And facing each other while holding the molding space of the container between them, and after placing a dummy mold in the corresponding portion of the ventilation portion in the molding space, poured molten polyurethane resin into the molding space, After the solidification, the mold and the core are opened to take out the molded product, and then the polyurethane piece is separately molded with respect to the opening formed by the dummy mold and the small hole serving as the ventilation portion is formed therethrough. It is characterized by being fitted with its inner surface being flush with the surroundings.

According to a second aspect of the present invention, in the first aspect of the present invention, a steel plate to which the polyurethane piece can be attached is fixed to a portion of the mold facing the dummy mold, and the polyurethane plate is fixed in that state. A molded product in which the plate is inserted is obtained by pouring resin, and then the polyurethane piece is attached through the plate.

<Invention of Claim 1>
In the present invention, since the entire container is manufactured by casting which does not cause distortion such as springback after molding, the thickness is kept uniform even if there is a vent, and even if a piece with a small hole is fitted later There is no step.

<Invention of Claim 2>
Since the polyurethane piece is attached via the steel plate, it is easy to attach and the reinforcement around the ventilation portion can be achieved.

  Next, an embodiment of the present invention will be described with reference to FIGS.

  6 of FIG. 6 shows the barrel tank of the present invention. The barrel tank 1 includes a container 2 and a lid 3. The container 2 is made of an elastic material, and here, a polyurethane resin is formed by a casting manufacturing method described later. This polyurethane resin has a hardness of 70 according to JIS K 6253 durometer hardness type A. In dry barrel polishing, since there is no water as a buffering agent, the workpiece collides with the wall surface of the container 2 with a strong impact, so that a dent is easily generated. However, if the hardness of the container 2 is set in this way, the dents can be reduced. Regarding the hardness, if it is less than 60, the performance is inferior due to the problem of mechanical strength. Moreover, since it will become easy to produce a dent when it exceeds 80, the range of 60 to 80 is preferable with durometer hardness type A. In this example, a polyurethane resin is used as the material of the container 2, but a thermosetting resin that can be solidified by casting, such as a polyester resin, can be used.

  The container 2 has a hexagonal cross section, and both ends are thick portions 2a in order to reinforce the container 2. Ventilation portions 25a and 25b are formed on two surfaces of the container 2 in the circumferential direction. The ventilation portions 25a and 25b are large openings, and are large enough to allow, for example, a grinding stone and / or a workpiece to pass through. Around these ventilation portions 25a and 25b, steel plates 6a and 6b are embedded in the container 2 together with polyurethane casting. In addition, polyurethane pieces 5a and 5b having small holes 4 through which polishing stones and workpieces cannot pass can be fitted into the ventilation portions 25a and 25b from inside the container, and are fixed to the plates 6a and 6b with bolts and nuts. Has been. The polyurethane pieces 5a and 5b and these small holes 4 are also produced by casting.

  On the other hand, the opening 2b of the container 2 uses one surface in the circumferential direction, from which a work and a grinding stone are put. The opening 2b is a seal 2c formed in a protruding shape so that the opening 2b can be sealed when the lid 3 is closed. A rectangular frame 7 is embedded in the container 2 together with a polyurethane casting for reinforcement purposes around the seal 2c, but this is not always necessary. A connecting plate 24 is screwed to the frame 7 and a container carrying bar 8 is attached.

  Next, the manufacturing method of the container 2 of this invention is demonstrated based on FIG. Here, the inner surface of the mold 30 has the shape of the container 2, and is divided into 30a, 30b, and 30c so that the casting material can be taken out after being cooled and solidified to become the container 2. A bridge 31 is placed over the upper end of the mold 30, and a core 32 is suspended from the bridge 31. The core 32 is also divided into 32a and 32b so that the container 2 can be taken out from the container after being cooled and solidified. The plates 6a and 6b and the frame 7 are screwed to the corresponding molds (not shown). Dummy molds 33a and 33b are attached to the portions corresponding to the ventilation portions 25a and 25b via the plates 6a and 6b, and the thickness obtained by adding the dummy molds 33a and 33b and the plates 6a and 6b is the same as that of the container 2. ing.

  After setting the mold 30, the bridge 31, the core 32, the plates 6a and 6b, the frame 7, and the dummy molds 33a and 33b, a molten polyurethane resin is poured. When the resin is solidified, the core 32, the bridge 31, the mold 30, the dummy molds 33a and 33b are disassembled in this order to form the barrel tank container 2 of the present invention.

  Next, the lid 3 will be described with reference to FIGS. The base 10 of the lid 3 is made of a lightweight alloy such as aluminum, and a polyurethane lining 9 made of the same material as the container 2 is attached to the side facing the container 2 by casting. Two handles 11 are provided on the upper surface of the base 10 so that the lid 3 can be easily attached and detached. In order to close the lid 3 to the container 2, in order to press with the clamp shaft 21 mentioned later, the surface which the clamp shaft 21 contacts is provided with the friction plate 12. FIG. The base 10 is provided with a clamp shaft locking mechanism 26 for rotating the clamp shaft 21 to close the lid 3. In the lock mechanism 26, the spring 14 is attached to the rod 13, and the spring 14 is located between the insertion plates 15a and 15b, so that the rod 13 is always biased toward the insertion plate 15c.

  Next, the closing mechanism of the lid 3 will be described with reference to FIGS. Reference numeral 16 denotes a barrel case that accommodates the barrel tank 1 and is attached to the rotation shaft 17a and the hollow rotation shaft 17b. A partition plate 18 is provided in the barrel case 16 with a certain space therebetween, and supports the barrel tank 1 via a rectangular sponge rubber 19. Inside the sponge rubber 19, the partition plate 18 is cut out in a rectangular shape like the sponge rubber to form a cutout 18 a. On the other hand, a side plate 20 is bolted to the upper end of the barrel case 16 so as to hold the clamp shaft 21 rotatably. An eccentric cam 22 is formed on the clamp shaft 21 with respect to the rotation axis. When the clamp shaft 21 is inserted into the side plate 20 and rotates in the direction indicated by the arrow A with the center gripping shaft 21 a, the eccentric cam 22 is attached to the lid 3. The friction plate 12 is pressed to close the lid 3 with respect to the container 2. At this time, since the sponge rubber 19 is present on the bottom surface of the container 2, the sponge rubber 19 is compressed to keep the space between the barrel tank 1 and the partition plate 18 airtight.

  Such a barrel tank 1 is accommodated in a barrel case 16, and a rotation shaft 17a and a hollow rotation shaft 17b are mounted on the circumference of two revolution turrets 23 so as to be capable of rotation at equal intervals, and are arranged in four places in this example. (FIG. 13).

  Next, a case where a workpiece is polished using the barrel tank 1 will be described. A grinding stone and a work are put in from the opening 2b of the container 2. Next, the barrel tank 1 is mounted on the barrel case 16, and the lid 3 is placed on the opening 2b. Next, the barrel tank 1 is fixed to the barrel case 16 by inserting the clamp shaft 21 into the side plate 20 and rotating the clamp shaft 21 in the direction indicated by the arrow A with the gripping shaft 21a. Further, if the rod 13 of the lock mechanism 26 is retracted against the spring 14 in advance and the gripping shaft 21a is rotated and then the rod 13 is returned, the gripping shaft 21a is fixed by the rod 13 and can be prevented from rebounding. . In this state, when the turret 23 revolves in the direction indicated by arrow D and the rotation shaft 17a and the hollow rotation shaft 17b rotate in the direction indicated by arrow E, the barrel tank 1 receives the rotation and revolution action and polishes the workpiece.

  By the way, the barrel tank 1 has ventilation portions 25a and 25b. The ventilation portion 25b faces the partition plate 18. The partition plate 18 has a notch 18a and is spatially connected to the hollow portion of the hollow rotation shaft 17b via the lower surface of the partition plate 18. The tip of the hollow rotating shaft 17b is connected to a dust collector (not shown), and during the polishing, the dust collector acts to suck air into the barrel tank 1 and fit the polishing dust and dust into the ventilation portion 25b. The gas is discharged from the small hole 4 of 5b and is collected to the dust collector through the exhaust passages B and C. At this time, the sponge rubber 19 is compressed on the bottom surface of the barrel tank 1 to keep the container 2 and the partition plate 18 airtight, so that the air flows smoothly like the exhaust paths B and C. On the other hand, since air is introduced from the small holes 4 of the polyurethane piece 5a of the ventilation portion 25a with the dust collecting action, the introduction of air cools the inside of the barrel tank 1 and discharges polishing dust and dust. The stone is not clogged, and the workpiece is polished well with no contamination.

  In this example, the polyurethane pieces 5a and 5b are bolted to the plates 6a and 6b. However, the plates 6a and 6b are not always necessary, and the polyurethane pieces 5a and 5b may be directly attached to the ventilation portions 25a and 25b. In the above example, the barrel tank 1 is attached to a device that rotates and revolves, but may be attached to a rotating barrel polishing device that only rotates. One or two or more ventilation portions may be formed. In short, it is only necessary that air can be introduced and polishing waste and dust can be discharged.

  As described above, the barrel tank for dry barrel polishing according to the present invention formed the entire container by casting without using a conventional steel casing. Is kept uniform, and a step does not occur even if a piece having a small hole of the same thickness is fitted later. Moreover, since the container is made of an elastic material such as polyurethane resin, it is lightweight and can reduce the burden of carrying work. If a polyurethane resin with high wear resistance is used, the barrel tank can be used over a long period of time, and the polyurethane wall thickness is thicker than that of a steel casing barrel tank, so that it can withstand long-term use. Furthermore, since the polyurethane resin hardness is 60 to 80 in the durometer hardness type A, the impact of the workpiece hitting the inner wall of the container is reduced even in a dry barrel that has no buffering action compared to the wet barrel, leading to a reduction in the dents.

The perspective view which shows the production procedure of the conventional barrel tank housing Similarly, a cross-sectional view showing how the core is set in the housing and the elastic material is cast A perspective view of the barrel tank with the same lining Sectional view of a conventional dry polishing barrel 4b partially enlarged cross-sectional view of FIG. Front view of barrel tank of the present invention Same top view Same side view Front sectional view of the barrel tank of the present invention Same side sectional view Front sectional drawing which shows the state which attached the container of this invention to the barrel case, and was covered Same side sectional view Side surface sectional view which shows the state which attached the barrel tank of this invention to the turret Sectional drawing which showed a mode that the barrel tank container of this invention was manufactured

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Barrel tank 2 ... Container 3 ... Cover 25a ... Ventilation part 25b ... Ventilation part

Claims (2)

A method for producing a dry barrel polishing container in which a vent for circulation of outside air is formed on a side surface,
The mold and the core that can be opened and closed are opposed to each other while holding the molding space for the container therebetween, and a dummy die is disposed at a corresponding portion of the ventilation portion in the molding space, and then the molding is performed. A molten polyurethane resin is poured into the space, and after the solidification, the mold and the core are opened to take out a molded product, and then a small hole that is separately molded with respect to the opening formed by the dummy mold and serves as the ventilation portion A method for producing a dry barrel polishing container, comprising: inserting a polyurethane piece having a through hole in a state where its inner surface is flush with the periphery. A steel plate to which the polyurethane piece can be attached is fixed at a position facing the dummy mold in the mold, and the polyurethane resin is poured in that state so that the plate is inserted. 2. The method for producing a dry barrel polishing container according to claim 1, wherein the polyurethane piece is attached through the plate.

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