JP3924469B2 - Clean room wheel unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In a clean room such as a sterilization chamber for sterilizing tableware or a dust-free chamber for assembling semiconductors, for example, the article mounting pallet travels along a guide wheel, or a wheel of a traveling cart is used as a guide rail It is related with the wheel unit used for making it run along.
[0002]
[Prior art and problems]
Generally, a wheel such as a carriage can be smoothly rotated by a bearing interposed between the support shaft and the bearing is essential for the wheel. These bearings include a sliding bearing made of a sleeve or the like and a rolling bearing made of a ball, a roller, or the like. If any bearing receives a considerable load, lubrication with oil is required.
[0003]
However, in the case of a wheel used in a clean room as described above, if oil is used, dust and the like are likely to adhere, and the attached dust and the like tend to generate fungi. This makes it difficult to smoothly rotate the wheel, which makes it difficult to use the wheel within a short period of time due to the generation of metallic noise during use and worsening the working environment. There was a problem that said.
[0004]
An object of this invention is to provide the wheel unit for clean rooms which can rotate a wheel smoothly and can extend a service life in view of said problem.
[0005]
[Means for Solving the Problems]
In the clean room wheel unit according to the first aspect of the present invention, the wheel main body 2 supported by the support shaft 1 is divided into a metal inner ring body 2a and an outer ring body 2b, respectively, and an inner ring wheel is formed. Between the body 2a and the outer ring 2b, metal bearing rollers 4 arranged in the circumferential direction are inserted in approximately one half of the wheel width, and self-lubricating properties are provided on the opposite side. In addition, a first bearing sleeve 5 made of a fluororesin-based material having excellent wear resistance is inserted, and the same fluororesin as that of the first bearing sleeve 5 is interposed between the support shaft 1 and the inner ring 2a. A second bearing sleeve 6 made of a system material is inserted, and brackets 3 and 3 are attached to the support shaft 1 to support both end faces of the two wheels 2a and 2b.
[0006]
According to a second aspect of the present invention, in the clean room wheel unit according to the first aspect, the bearing sleeves 5 and 6 are made of the same material between both end faces of the two wheel bodies 2a and 2b and the brackets 3 and 3, respectively. A thrust washer 7 is interposed.
[0007]
According to a third aspect of the present invention, in the clean room wheel unit according to the first or second aspect, an annular outer cover member 18 made of a fluororesin material is attached to the outer periphery of the outer peripheral ring body 2b.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a partially sectional front view of a clean room wheel unit WU according to the present invention, and FIG. 2 is an exploded sectional view showing the wheel unit WU in an exploded state. 1 and 2, a wheel unit WU of the present invention includes a support shaft 1, a wheel body 2 supported by the support shaft 1, the support shaft 1 and the both ends of the wheel body 2. And a bearing member (bearing roller 4, first bearing sleeve 5, second bearing sleeve 6 and thrust washer 7).
[0009]
The structure of the wheel unit WU will be described in detail. The support shaft 1 is made of stainless steel, and as can be seen from FIG. 2, a bearing portion 1a and screw shaft portions 1b and 1b formed at both ends thereof. Consists of. The wheel main body 2 is divided and formed by an inner peripheral side ring body 2a and an outer peripheral side ring body 2b each made of stainless steel, and there is a wheel between the inner peripheral side ring body 2a and the outer peripheral side ring body 2b. Fluorine resin having self-lubricating property and excellent wear resistance on the opposite side of a plurality of stainless steel bearing rollers 4 that are arranged in the circumferential direction in the half of the width. A first bearing sleeve 5 made of a system material is inserted.
[0010]
A second bearing sleeve 6 made of the same fluororesin material as that of the first bearing sleeve 5 is interposed between the inner peripheral ring body 2a of the first bearing sleeve 5 and the support shaft 1, and the inner and outer sides are inserted. Thrust washers 7 and 7 made of the same material as the first and second bearing sleeves 5 and 6 are inserted between both end faces of both the ring bodies 2a and 2b and the brackets 3 and 3, respectively.
[0011]
As can be seen from FIGS. 3 and 4, the inner peripheral side wheel body 2 a of the wheel body 2 has a flange portion 9 protruding from one end portion in the axial direction of the base tube portion 8, and on the outer periphery side of the base tube portion 8. Forms an annular convex step portion 10 from the flange portion 9 to the intermediate portion in the axial direction of the base tube portion 8, and a plurality of substantially C-shaped cross sections extending in parallel to the axial direction of the base tube portion 8 on the annular convex step portion 10. A roller-shaped fitting groove 11 is formed so as to open on the outer peripheral surface of the annular convex step portion 10 at regular intervals in the circumferential direction. An annular recess 23 is formed in a portion adjacent to the direction, and each roller fitting groove 11 of the annular projecting step portion 10 has a cylindrical bearing roller 4 in which both end portions 4a and 4a are formed in a hemispherical round shape. It is fitted so as to be rotatable around and axially detachable. An annular ridge 12 having a semicircular cross section is provided on the inner side of the front end of the flange 9, and an annular ridge 13 is formed on the inner periphery of the annular ridge 12.
[0012]
As shown in FIG. 2, the outer peripheral side wheel body 2 b of the wheel main body 2 has a flange portion 15 projecting outward at one axial end portion of the base tube portion 14, and an inner peripheral surface of the base tube portion 15. An inward annular convex portion 16 is provided on one end side, and an annular concave portion 24 is formed on the inner peripheral side of the base tube portion 14 at a portion adjacent to the inward annular convex portion 16 in the axial direction. An annular convex portion 17 having a semicircular cross section is provided on the outer end surface of the annular convex portion 16. Further, as shown in FIG. 1, an annular jacket member 18 made of Teflon (registered trademark), which is a fluororesin material, is mounted on the outer peripheral surface of the outer peripheral ring body 2b.
[0013]
In FIGS. 1 and 2, reference numeral 19 denotes a ring-shaped spacer made of a fluororesin material similar to that of the outer cover member 18, and the bearing roller 4 interposed between the inner and outer ring bodies 2a and 2b. It is inserted between each one end part and the annular convex part 16 of the outer peripheral side ring body 2b to prevent the bearing roller 4 from rattling in the axial direction. Reference numeral 20 denotes a nut for fixing the bracket 3 that supports both end faces in the axial direction of both the ring bodies 2a and 2b to the support shaft 1. Each bracket 3 is formed in an L shape by a main body portion 3a and an attachment portion 3b. The main body portion 3a has a spindle insertion hole 21 and the attachment portion 3b has a bolt insertion hole 22 for fixing the bracket. Is provided.
[0014]
The fluororesin-based material having a self-lubricating property and excellent wear resistance, which is a material for forming the first bearing sleeve 5, the second bearing sleeve 6 and the thrust washer 7, is polytetrafluoroethylene (PTFE). Is a high-performance sliding material formed by adding a filler such as glass fiber or molybdenum disulfide to the base resin. Specifically, it is manufactured by NTN Corporation and is manufactured by “Beary FL3000” and “Bearly”. Those sold under a trade name such as “FL3700” can be used.
[0015]
The above features such as “Bearly FL3000” and “Bearly FL3700” are highly self-lubricating, can be used without lubrication as a bearing material, eliminate the need for lubricating oil, have a low friction coefficient, and have excellent wear resistance. It has good compatibility with mild steel and stainless steel, and also has excellent heat resistance, weather resistance, and chemical resistance. With regard to heat resistance, it can sufficiently withstand high temperatures of about 220 ° C.
[0016]
In assembling the wheel unit WU composed of the above-described components, as shown in FIGS. 1 and 2, first, the second bearing sleeve 6 is externally fitted to the bearing portion 1a of the support shaft 1, and the second bearing The inner peripheral side ring body 2 a is fitted to the sleeve 6. A bearing roller 4 is inserted into each roller fitting groove 11 provided in the annular convex step portion 10 of the base tube portion 8 on the inner peripheral ring body 2a, and the annular recess 23 side of the outer peripheral surface of the base tube portion 8 is inserted. The first bearing sleeve 5 is externally fitted to the first.
[0017]
Thereafter, the outer peripheral side ring body 2b is fitted into the inner peripheral side ring body 2a, and the annular convex step portion 10 of the inner peripheral side ring body 2a is concavo-convexly fitted into the annular concave portion 24 of the outer peripheral side ring body 2b. The annular convex portion 16 of the outer peripheral ring body 2b is concavo-convexly fitted into the annular concave portion 23 of the inner peripheral ring body 2a, and at the same time, the inner end face of the annular convex step portion 10 of the inner peripheral ring body 2a and the outer peripheral ring body 2b. By interposing a spacer 19 with the inner end surface of the annular step portion 16, a wheel body 2 composed of both inner and outer wheels 2a, 2b is formed, and a thrust washer 7 abutting against both end surfaces of the wheel body 2, 7 is fitted into the support shaft 1, and nuts 20 and 20 are fitted into both ends of the support shaft 1 and tightened to assemble the wheel unit WU. The wheel unit WU can be easily disassembled in the reverse order of the above assembly. Since the wheel unit WU is easy to disassemble and assemble as described above, the wheel unit WU can be easily cleaned and is optimal as a wheel unit used in a clean room.
[0018]
In the wheel unit WU assembled as described above, the outer peripheral side ring body 2b of the wheel main body 2 is interposed between the inner peripheral side ring body 2a and the one half of the wheel width and the bearing roller 4 and its The inner ring 2a is rotatably supported by the inner ring 2a via the first bearing sleeve 5 inserted on the opposite side, and the inner ring 2a is supported by the support shaft 1 via the second bearing sleeve 6. The both end surfaces of the inner and outer ring bodies 2a and 2b are rotatably supported with respect to the brackets 3 and 3 on both sides via thrust washers 7 and 7, respectively. The bearing rollers 4 fitted in the respective roller fitting grooves 11 on the inner peripheral side ring body 2a side are in line contact with the inner peripheral surface of the base cylinder part 14 of the outer peripheral side ring body 2b. Both end portions 4 a and 4 a of the bearing roller 4 are in point contact with the back end surface 11 a (see FIG. 4) of each roller fitting groove 11 and the spacer 19.
[0019]
Therefore, the wheel unit WU is used as a pallet guide wheel disposed on a sterilization chamber frame 30 for sterilizing tableware or the like as shown in phantom lines in FIG. When the unit WU guides the pallet 31 loaded with the dishes to be sterilized, the wheel body 2 of the wheel unit WU rotates with the movement of the pallet 31 loaded with the dishes. Depending on the direction and size of the load applied to the main body 2, the rotation state varies. In FIG. 1, reference numeral 32 denotes a bolt / nut that fixes the bracket 3 to the mount 30 using the bolt insertion hole 22 of the bracket 3.
[0020]
That is, when the pallet 31 travels and travels, when the vertical load (load in the direction orthogonal to the support shaft 1) is applied to the wheel body 2, the inner peripheral side ring body 2a and the outer peripheral side ring body 2b are usually used. Are rotated around the support shaft 1 together with the second bearing sleeve 6 inserted between the inner peripheral ring body 2a and the support shaft 1. In this case, even if the vertical load applied to the wheel body 2 is considerably large and the rotation speed is high, the second bearing sleeve 6 is made of a high performance sliding material having a self-lubricating property and a small friction coefficient. The wheel body 2 can smoothly rotate without causing the second bearing sleeve 6, the support shaft 1, or the inner peripheral ring body 2 a to generate heat or generate abnormal noise.
[0021]
Further, during the traveling movement of the pallet 31, in addition to the vertical load on the wheel body 2, the pallet 31 slides sideways and a lateral load (thrust load) along the axial direction of the wheel body 2 acts, and the inner circumference When the end face on the flange 9 side of the side ring 2a or the end face on the flange 15 side of the outer ring 2b is pressed against the bracket 3 via the thrust washer 7, the inner ring 2a of the wheel body 2 is The outer ring body 2b may rotate relative to the inner ring body 2a while still.
[0022]
When the outer ring 2b rotates while the inner ring 2a is stationary as described above, the outer ring 2b is inserted into one side of the wheel width with the inner ring 2a. The bearing roller 4 and the first bearing sleeve 5 inserted on the opposite side are rotatably supported by the inner ring body 2a, and both end surfaces of both the ring bodies 2a and 2b and the bracket. 3 and 3, thrust washers 7 and 7 are inserted, respectively, and the bearing roller 4 is in a line contact state with the inner peripheral surface of the base tube portion 14 of the outer peripheral ring body 2b and both end portions of the bearing roller 4 4a and 4a are in point contact with the back end surface 11a of each roller fitting groove 11 and the spacer 19, so that even if the vertical load or the lateral load applied to the wheel body 2 is considerably large, the vertical load is a bearing. It can be supported by the rollers 4 and the lateral load is Since it is supported by the washer 7, the wheel body 2 can be prevented from being damaged by the vertical load and the lateral load, and the second bearing sleeve 6 and the thrust washer 7 made of the same material as the second bearing sleeve 6 can be used. 6 and the thrust washer 7 do not generate heat or generate abnormal noise, so that the outer peripheral ring body 2b can be smoothly rotated and the service life can be extended.
[0023]
Further, when the outer peripheral side ring body 2b rotates with respect to the inner peripheral side ring body 2a, an annular convex part 12 having a semicircular cross section is provided on the inner side surface of the front end of the flange part 9 of the inner peripheral side ring body 2a In addition, since an annular convex portion 17 having a semicircular cross section is provided on the end surface of the outer peripheral side ring body 2b on the flange 15 side, the annular convex portion 12 of the inner peripheral side ring body 2a is provided on the outer peripheral side. The ring body 2b or the outer surface of the outer ring member 2b is in line contact with the opposite end surface of the ring member 2b or the outer cover member 18, and the annular convex portion 17 of the outer ring member 2b is in line contact with the thrust washer 7 to the inner ring member 2a. The rotation of the outer peripheral side ring body 2b can be further smoothed.
[0024]
Further, while the use of the wheel unit WU as described above is repeatedly performed over a long period of time, for example, the wheel unit WU is inserted between the inner ring body 2a and the outer ring body 2b of the wheel body 2. Even if the first bearing sleeve 5 is worn and damaged, the metal bearing roller 4 is inserted between the two wheel bodies 2a and 2b together with the first bearing sleeve 5. The load applied to the outer peripheral ring body 2b can be sufficiently supported by the rollers 4, and the outer peripheral ring body 2b can be smoothly rotated.
[0025]
According to this wheel unit WU, the two bearing members of the bearing roller 4 and the first bearing sleeve 5 are interposed between the inner peripheral ring body 2a and the outer peripheral ring body 2b as described above. A bearing member comprising a second bearing sleeve 6 is interposed between the inner ring 2a and the support shaft 1, and between both end faces of both rings 2a, 2b and both brackets 3, 3. Since a kind of bearing member (thrust bearing member) composed of a thrust washer 7 is inserted, even if the bearing member between the two wheel bodies 2a and 2b is worn and damaged, the inner ring body 2a and the support shaft 1 are provided. The wheel body 2 can be smoothly rotated by the bearing member between the two, and if the bearing member between the inner peripheral side wheel body 2a and the support shaft 1 is worn and damaged, the space between the two wheel bodies 2a and 2b can be reduced. The wheel body 2 can be smoothly rotated by the bearing member. One of the washer 7, 7 can support the lateral load applied to the wheel body 2 by the other thrust washer 7 be worn damaged.
[0026]
In the embodiment described above, both brackets 3 and 3 are provided with attachment portions 3b, respectively, and both brackets 3 and 3 are attached to the pedestal 30, but only one bracket 3 is provided with attachment portions 3b and the opposite side. The bracket 3 may be composed of only the main body 3a, and the bracket 3 on the side having the mounting portion 3b may be mounted in a cantilevered state at a predetermined location such as the gantry 30 when mounting the wheel unit WU.
[0027]
【The invention's effect】
In the clean room wheel unit according to the first aspect of the present invention, the wheel main body is divided and formed by a metal inner ring body and an outer ring body, and a metal bearing roller and self A first bearing sleeve made of a fluororesin material having lubricity and excellent wear resistance is inserted, and the same material as that of the first bearing sleeve is interposed between the support shaft and the inner ring. The second bearing sleeve is interposed, and no lubricating oil is used for the bearing member, and only the outer peripheral ring is changed to the inner peripheral ring according to the load applied to the outer peripheral ring. It is possible to smoothly rotate the outer peripheral ring body with respect to the body and the spindle in an integrated state with the inner peripheral ring body, and to extend the service life of the wheel.
[0028]
Further, a metal bearing roller is inserted in one side of the wheel width between the inner peripheral side ring and the outer peripheral side ring, and a first bearing sleeve made of the fluororesin material is inserted in the opposite side part. Therefore, even if a considerably large vertical load is applied to the outer ring body, the outer ring body can be smoothly rotated by the first bearing sleeve while the load is received by the metal bearing roller. There is no such thing as damaging the wheel body. In particular, since a bearing roller, that is, a cylindrical bearing member is used, it is easier to install between the inner and outer ring bodies than the ball bearing member, and it can be stably mounted between the both ring bodies, resulting in production. Becomes easy.
[0029]
Further, according to this wheel unit, even if the bearing member between the inner peripheral ring body and the outer peripheral ring body is worn and damaged, the wheel main body is supported by the bearing member between the inner peripheral ring body and the support shaft. The wheel body can be rotated smoothly, and even if the bearing member between the inner ring and the support shaft is worn and damaged, the wheel body can be smoothly rotated by the bearing member between the two rings. Even if the first bearing sleeve, which is one of the bearing members between the outer ring and the outer ring, is worn and damaged, it can be rotated by the bearing roller on the opposite side. Rotation is maintained. Furthermore, since this wheel unit is easy to disassemble and assemble and is easy to clean, it is most suitable as a wheel unit for a clean room.
[0030]
According to a second aspect of the present invention, there is provided a wheel unit in which a thrust washer made of the same material as the first and second bearing sleeves is interposed between both end faces of both the inner and outer ring bodies and both brackets. Even if a lateral load is applied to the body and the outer peripheral side wheel body, each wheel body does not generate heat or generate an abnormal noise by supporting the lateral load with a thrust washer. The body can be rotated smoothly. Therefore, according to this wheel unit, both the vertical load and the lateral load applied to the wheel body can be supported by the bearing member made of a fluororesin material having self-lubricating properties and excellent wear resistance. Therefore, the wheel can be rotated smoothly at all times, and the service life can be extended.
[0031]
According to the wheel unit of the invention according to claim 3, by mounting an annular outer cover member made of a fluororesin material on the outer periphery of the outer peripheral ring body, the member that comes into contact with the outer peripheral ring body when the wheel unit is used. Sliding is improved and workability is improved by using the wheel unit.
[Brief description of the drawings]
FIG. 1 is a partially sectional front view of a clean room wheel unit according to the present invention.
FIG. 2 is an exploded sectional view of the wheel unit.
FIG. 3 is a perspective view showing an inner peripheral ring body and a bearing roller.
4A is a front view of an inner peripheral side ring body, and FIG. 4B is a sectional view taken along line XX of FIG. 4A.
[Explanation of symbols]
WU Wheel unit 1 Support shaft 2 Wheel body 2a Inner ring body 2b Outer ring body 3 Bracket 4 Bearing roller 5 First bearing sleeve 6 Second bearing sleeve 7 Thrust washer 18 Jacket member

Claims (3)

A wheel main body 2 supported by the support shaft 1 is divided and formed by an inner circumferential ring body 2a and an outer circumferential ring body 2b made of metal, and between the inner circumferential ring body 2a and the outer circumferential ring body 2b. A metal bearing roller 4 arranged in the circumferential direction is inserted in a half of one side of the wheel width, and a fluororesin material having self-lubricating properties and excellent wear resistance is provided on the opposite side portion. The first bearing sleeve 5 is inserted, and the second bearing sleeve 6 made of the same fluororesin material as the first bearing sleeve 5 is inserted between the support shaft 1 and the inner peripheral ring body 2a. A clean room wheel unit in which brackets 3 and 3 for supporting both end surfaces of both the wheel bodies 2a and 2b are attached to the support shaft 1. The clean room wheel according to claim 1, wherein a thrust washer (7) made of the same material as that of the bearing sleeve (5, 6) is inserted between both end faces of the two wheel bodies (2a, 2b) and the brackets (3, 3). unit. The wheel unit for a clean room according to claim 1 or 2, wherein an annular outer covering member 18 made of a fluororesin material is attached to the outer periphery of the outer peripheral ring body 2b.

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