KR101305383B1 - Plate reducer - Google Patents

Abstract

Disclosed are a plate type reducer having a large drive torque, stable driveability, and a small and mass-producible structure.
The disclosed plate reducer includes: an input shaft which is rotationally driven by power provided from a drive source; An actuating portion provided on the input shaft such that the plate surface is inclined with respect to a plane perpendicular to the rotation axis line of the input shaft at a predetermined position of the input shaft, and in association with rotation of the input shaft, the plate surface reciprocates meandering with respect to the rotation axis direction of the input shaft; A rolling element movable by the operating unit in the direction of the rotation axis of the input shaft; A rotation guide groove is formed on a surface facing the rolling element and is rotated by the pressing force of the rolling element; And a housing having a guide groove for guiding the rolling element to move in the axial direction of the input shaft.

Description

Plate Reducer {PLATE REDUCER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed reducer, and more particularly, to a plate type speed reducer having a large driving torque, a stable driveability, and a structure capable of producing a small size and mass.

In general, a speed reducer is a device that receives a high speed rotational force output from a driving source such as a motor, and decelerates and outputs a low speed rotational force. Harmonic reducers, planetary reducers, cycloid reducers, and RV reducers are widely known according to the deceleration method.

Among them, the harmonic reducer includes a circular spline having internal gears and a flexible spline having external gears to engage the internal gear of the circular spline, and is generated by the difference in the number of gear teeth of the circular spline and the flexible spline. By using the relative rotation is reduced the input high-speed rotational force to a low speed.

The cycloid reducer includes a pin gear having an internal tooth of a predetermined tooth shape having a pin inserted therein; A cam member provided on the crankshaft translates in the radial direction of the input shaft, and includes an eccentric gear having an external tooth of a cycloid tooth having a predetermined number of teeth and an internal tooth. This cycloidal speed reducer decelerates the input high-speed rotational force at a low speed by using the relative rotation of the pin gear generated by the gear tooth difference between the inner tooth of the pin gear and the outer tooth of the eccentric gear.

Recently, as the speed reducer has been diversified in not only industrial facilities such as semiconductor production lines, but also humanoid robots, miniaturization, stable driveability, and ease of mass production are required.

On the other hand, the above kinds of reducers have a difficult problem to be solved in order to achieve miniaturization, stable driveability and ease of manufacture. For example, in the case of a harmonic reducer, it is relatively easy to miniaturize, but it is difficult to realize a relatively stable drive due to stiffness and vibration characteristics. Cycloid reducer is relatively large driving torque (torque) and a small backlash (backlash) is possible to drive stable, while the disadvantage of the relatively small size by the configuration of the crankshaft.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described points, and has an object of providing a plate type reducer having a large driving torque, a stable driving property, and a small and mass-producible structure.

In order to achieve the above object, the plate reducer according to the present invention comprises: an input shaft driven to rotate by power provided from a drive source; The plate surface is installed on the input shaft such that the plate surface is inclined with respect to the plane perpendicular to the rotation axis of the input shaft at a predetermined position of the input shaft, and the plate surface reciprocates meandering with respect to the rotation axis direction of the input shaft in conjunction with the rotation of the input shaft. An actuating unit; A rolling element movable by the operation unit in a direction of the rotation axis of the input shaft; An output unit having a rotation guide groove formed on a surface opposing the rolling element, and being rotated by a pressing force of the rolling element; And a housing having a guide groove for guiding the rolling element to move in an axial direction of the input shaft.

The operating unit includes an input bearing installed on the input shaft; It may be installed so as to be relatively rotatable with respect to the input bearing, and may include a working plate for pressing the rolling element toward the output unit.

The input bearing includes: an input inner ring having an insertion hole formed to be inserted into the input shaft and having a ball seat formed at an outer surface thereof; An input outer ring inserted into the hollow of the operation plate and having a ball seat formed therein; It may include a movable body installed in the ball seat of each of the input inner ring and the input outer ring to enable a rolling motion. Here, the input outer ring may be formed integrally with the operating plate.

In addition, the insertion hole may be formed in the input inner ring such that the central axis of the input inner ring insertion hole is inclined at a predetermined angle with respect to the axis of the input shaft.

The ball seat may be formed on the input inner ring such that the plate surface of the input inner ring is inclined at an angle with respect to a plane perpendicular to the rotation axis.

In addition, the outer circumferential surface on which the ball seat of the input inner ring is formed may be formed in a round shape.

The rolling element may include a first electric motor and a second electric motor provided on both sides of the operating plate. In this case, the output unit includes: a first carrier having a first rotation guide groove formed on one side of the operating plate opposite to the operating plate with the first motor body interposed therebetween; A second carrier having the second motor body interposed therebetween, the second carrier being provided opposite to the other side of the operation plate, and having a second rotation guide groove formed on one surface of the operation plate opposite to the operation plate; It may include a carrier pin for coupling the first carrier and the second carrier so that the movement of the first carrier and the second carrier are interlocked with each other.

Each of the first and second rotation guide grooves may be formed in at least one of a cycloid tooth, an involute tooth, and an arc tooth.

The operating plate may further include: a first pressing piece for elastically pressing the first electric body in the first carrier direction; The first pressing piece may be spaced apart from each other by a predetermined interval, and may include a second pressing piece for elastically pressing the second motor body in the second carrier direction.

In addition, the plate-type reducer according to the present invention may further include a support member interposed between the operating unit and the output unit for supporting the rolling element.

The rolling element may include at least one of a plurality of rigid balls and a plurality of rigid needles.

The input shaft may be formed in a hollow cylindrical shape.

In addition, the plate-type speed reducer according to the present invention includes a first bearing interposed between the input shaft and the output unit, the first bearing for supporting the output unit to rotate independently with respect to the input shaft; It may further include a second bearing interposed between the output unit and the housing to support relative rotation between the output unit and the housing.

In addition, in the plate type reducer according to the present invention, at least one of the input shaft, the operation unit, the rolling element, the output unit and the housing may be made of an engineering plastic material. Here, the engineering plastics, polyacetal, polyphenylene oxide, polyamide, polycarbonate, polybutylene terephthalate, U polymer, polysulfone, polyphenylene sulfide, polyetherimide, polyether sulfone, polyarylate, Polyether ether ketone, ethylene tetrafluoroethylene, polychlorotrifluoroethylene, chlorotrifluoroethylene ethylene copolymer, perfluoroalkoxy, polyethylene terephthalate, high density molecular weight polyethylene, polyvinylidene fluoride, acrylonitrile butadiene styrene At least one selected from the group consisting of copolymer, nylon 6, cerazole, polyurethane, and polyamideimide.

The plate-type speed reducer according to the present invention configured as described above has a large driving torque, has a stable driveability without backlash, and has a plate-like structure, so that the speed reducer can be made slim and miniaturized.

In addition, the plate reducer according to the present invention can produce a large amount of each component through the sintering molding, there is an advantage that can increase the product productivity and lower the product cost.

In addition, the plate-type reducer according to the present invention has the advantage that by at least a part of the configuration made of engineering plastic, it is possible to reduce the manufacturing cost, and to improve the weight and product productivity.

1 is a partial cross-sectional perspective view showing a plate-type reducer according to a first embodiment of the present invention.
Figure 2 is an exploded perspective view showing a plate reducer according to a first embodiment of the present invention.
3A and 3B are cross-sectional views each showing a plate type reducer according to a first embodiment of the present invention.
4 is a view for explaining a modification of the input shaft of the plate type reducer according to the first embodiment of the present invention.
5 is a cross-sectional view showing a plate-type reducer according to a second embodiment of the present invention.
Figure 6 is an exploded perspective view showing a plate reducer according to a third embodiment of the present invention.
Figure 7 is a cross-sectional view showing the eccentric plate and the rolling element of the plate-type reducer according to the fourth embodiment of the present invention.

Hereinafter, a plate type reducer according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 to 2 are each a partial cross-sectional perspective view and an exploded perspective view showing a plate-type reducer according to a first embodiment of the present invention, Figures 3a and 3b is a cross-sectional view showing a plate-type reducer according to a first embodiment of the present invention . 4 is a view for explaining a modification of the input shaft of the plate type reducer according to the first embodiment of the present invention.

Referring to the drawings, the plate-type reducer according to the first embodiment of the present invention, the input shaft 10 is driven to rotate by the power provided from a drive source (not shown), and the operation unit 100 is installed on the input shaft 10 ), The rolling element 20 which is moved in the direction of the rotation axis 11 of the input shaft 10 by the operation unit 100, the output unit 200 which is decelerated and rotated by the pressing force of the rolling element 20, and the front The body 20 includes a housing 50 having a guide groove 51 for guiding the body 20 to move in the direction of the rotation axis 11 of the input shaft 10.

The input shaft 10 may be coupled to the output shaft of the drive source, or may be configured to the output shaft of the drive source when applied to the motor and reducer integrated structure. The input shaft 10 may be configured as a cylindrical shape as shown in FIG. 1, or may be configured as a hollow cylindrical input shaft 15 as shown in FIG. 4. Here, when the input shaft is composed of a hollow cylindrical input shaft 15, electrical wiring necessary for driving the motor through the hollow interior is possible, so that the electrical wiring arrangement of the apparatus main body to which the reducer is applied can be facilitated.

3A and 3B, the operation unit 100 is installed on the input shaft 100 such that the plate surface thereof is inclined with respect to a plane perpendicular to the rotation axis 11 of the input shaft at a predetermined position of the input shaft 10. That is, the first line segment 101 parallel to the plate surface of the operation unit 100 forms a predetermined inclination with respect to the second line segment 13 on a plane perpendicular to the rotation axis 11 of the input shaft.

To this end, the operation unit 100 may include an input bearing 110 installed on the input shaft 10 and an operation plate 120 installed to be relatively rotatable with respect to the input bearing 110. Here, the operation plate 120 presses the rolling element 20 in the direction of the output unit, such that the output unit 200 decelerates and rotates.

When the input shaft 10 rotates, the plate surface of the operation unit 100 reciprocates meandering with respect to the rotation axis 11 direction of the input shaft 10 in association with the rotation of the input shaft 10. 3A is a view showing a state where the upper end of the plate surface of the operation unit 100 is inclined to the left side, and the lower end of the plate surface of the operation unit 100 is inclined to the right side. When the input shaft 10 rotates half a turn in the state of FIG. 3A, the plate surface state of the operation unit 100 is changed to the state as shown in FIG. 3B. That is, the upper end of the plate surface of the operating unit 100 is inclined to the right side and the lower end of the plate surface of the operating unit 100 is inclined to the left side. Therefore, when the operating unit 100 is installed on the input shaft 10 as described above, the operating unit 100 reciprocates meandering with respect to the rotation axis line 11 direction of the input shaft 10 as the input shaft 10 rotates. do.

The input bearing 110 includes an input inner ring 111, an input outer ring 117, and a movable body 115. The input inner ring 111 has an insertion hole 111a formed to be inserted into the input shaft 10. On the outer surface of the input inner ring 111, a ball seat 113 for guiding the rolling motion of the movable body 115 is formed.

Here, in the input inner ring 111 to form the insertion hole 111a therein, the central axis 111b of the insertion hole 111a is a predetermined angle (angle θ) with respect to the rotation axis 11 of the input shaft 10. It may be formed to be inclined. Accordingly, by inserting the input inner ring 111 on the input shaft 10, the operating unit 100 can be inclined. The inclination angle θ between the central axis 111b of the insertion hole 111a and the rotation axis 11 of the input shaft 10 is the distance r between the rotation axis 11 and the operation unit 100 and actuated. It is set in consideration of the rotation axis direction moving distance d of the part 100. That is, the inclination angle θ may be set to tan ⁻¹ (d / r).

In addition, the outer circumferential surface on which the ball seat 113 of the input inner ring 111 is formed may be formed in a round shape. Preferably, the outer circumferential surface of the input inner ring 111 may be formed in a spherical shape having an origin on the center axis line 111b of the insertion hole 111a. In this case, in forming the insertion hole 111a inclined in the input inner ring 111, a tool for processing the insertion hole 111a can be installed using the outer circumferential surface of the input inner ring 111 as a reference plane. Thereby, the insertion hole 111a can be easily processed to the input inner ring 111. FIG.

The input outer ring 117 is inserted into the hollow of the operation plate 120 and the ball seat 117a is formed on the inner surface. The input outer ring 117 is not provided separately, as shown in Figure 2, it may be formed integrally with the operating plate 120. That is, by forming the ball seat 117a in the hollow inside of the operating plate 120 can replace the input outer ring. The movable body 115 is installed in the ball seat of each of the input inner ring 111 and the input outer ring 117 so as to enable rolling motion, and may be configured in a spherical shape, a cylindrical shape, and the like.

The input bearing 110 is to allow the operating plate 120 to reciprocate in the direction of the rotation axis 11 of the input shaft 10, consisting of a ball bearing as shown in Figures 1 to 4, or in Figure 5 It may be composed of an angular contact bearing 117 of the shape as shown. In the case of forming the angular contact bearing 117, since the movable body 117a is in contact with four points, there is an advantage that it can be stably supported in the journal and trust directions of the input shaft. In addition, the input bearing 110 may be configured as a cross roller bearing (not shown).

The output unit 200 has a rotation guide groove 201 is formed on the surface facing the rolling element 20. The operation plate 120 is meandered by the input bearing 110 in the direction of the rotation axis 11 of the input shaft 10, and presses the rolling element 20 in the direction of the rotation guide groove 201 of the output unit 200. do.

Here, the rolling element 20 is moved in the direction of the rotation axis 11 of the input shaft 10 by the operating unit 100, the first motor 21 and the first motor 21 is provided on each side of the operating plate 120 It may include a two-electric body 25. In this case, the output unit 200 may be rotated in conjunction with each of the first and second motors 21 and 25, so that the first carrier 210, the second carrier 220, and the carrier pin 230 are rotated. It may include.

The first carrier 210 is installed to face one side of the operation plate 120 with the first motor 21 therebetween. The first rotation guide groove 211 is formed on one surface of the first carrier 210 that faces the operating plate 120. The second carrier 220 is disposed to face the other side of the operation plate 120 with the second motor 25 therebetween. A second rotation guide groove 221 is formed on one surface of the second carrier 220 that faces the operating plate 120. Here, as a means for continuously rotating the first and second carriers 210 and 220, each of the first and second rotation guide grooves 211 and 221 has a cycloid tooth and an involute having a hill and a valley. Teeth, arc teeth, and the like.

The carrier pin 230 couples the first carrier 210 and the second carrier 220 through the operating plate 120 so that the movements of the first carrier 210 and the second carrier 220 interlock with each other. . That is, the carrier pin 230 is to fasten the first and second carriers 210 and 220 by passing through the through hole 120a formed in the operation plate 120, and the first and second motors 21 By each, the first and second carriers 210 and 220 are simultaneously moved. That is, when the input shaft 10 rotates from the state of FIG. 3B to the state of FIG. 3A, the first carrier 210 moves the first motor 21a positioned at the upper end of the plurality of first motors 21. Move in the direction of pressurization. In addition, the second carrier 220 moves in the direction of pressing the second motor 25b positioned at the lower end of the plurality of second motors 25.

At this time, the pressurized first motor body 21a moves in the direction of the rotation axis 11 of the input shaft 10 in a state in which the rotational direction movement is restricted by the guide groove 51 formed in the housing 50 so as to move the first carrier. The inclined surface 211a of the first rotation guide groove 211 formed in the 210 is pressed, and the pressed second motor 25b is inclined surface of the second rotation guide groove 221 formed in the second carrier 220. Press (not shown). As a result, the first carrier 210 rotates the input shaft 10 by a predetermined angle in the direction of rotation.

Subsequently, when the input shaft 10 rotates from the state of FIG. 3A to the state of FIG. 3B, the first carrier 210 is positioned at the lower end of the plurality of first motors 21. 21b moves in the pressing direction, and the second carrier 220 moves in the pressing direction of the second motor 25a located at the upper end of the plurality of second motors 25.

As a result, each of the first and second motors 210 and 220 that are pressurized presses each of the inclined surfaces of the first and second rotation guide grooves 211 and 221 so that the first carrier 210 receives the input shaft 10. ) Is rotated a predetermined angle in the same direction as the case described above with the rotation center.

Therefore, the above operation is repeated by the continuous rotation of the input shaft 10, so that the first and second carriers 210, 220 can be continuously rotated in a predetermined rotation direction.

In addition, the plate-type reducer according to the present invention may be interposed between the operation unit 100 and the output unit 220, and may further include a support member 70 for supporting the rolling element 20. That is, the support member 70 is provided inside the rolling member 20, and guides the rolling member 20 to be guided and moved in the guide groove 51 formed in the housing 50.

The rolling element 20 may include a plurality of rigid body balls 20a having a structure as shown in FIG. 2 or a plurality of rigid needles 120 having a structure as shown in FIG. 6.

In addition, the plate-type reducer according to the embodiment of the present invention may further include a first bearing 71 and the second bearing (75). The first bearing 71 is interposed between the input shaft 10 and the output unit 200 to support the output unit 200 to be independently rotated with respect to the input shaft 10. The second bearing 75 is interposed between the output unit 200 and the housing 50 to support the output unit 200 so as to rotate relative to the housing 50.

Referring to FIG. 7, the operation plate 120 includes a first pressing piece 121 for elastically pressing the first motor body 21 in the direction of the first carrier 210, and the first pressing piece 121. The second pressing body 125 may be spaced apart a predetermined interval and may include a second pressing piece 125 to elastically press the second electric motor 25 in the direction of the second carrier 220.

In addition, the plate-type reducer according to the present invention, in the manufacture of each component, the sintering molding can be manufactured integrally with the support member 70, the first carrier 210 and the carrier pin 230. Accordingly, there is an advantage that it is possible to increase the product productivity and lower the product cost.

In addition, the plate-type reducer according to the embodiment of the present invention may be configured of at least one of the input shaft 10, the operation unit 100, the rolling element 20, the output unit 200 and the housing 50 of the engineering plastic material. Can be.

Here, engineering plastics are high-performance resins of high rich structure whose physical properties are stronger than steel and rich in malleability than aluminum and gold / silver are more chemically resistant. The performance and characteristics vary depending on the chemical structure, and can be largely divided into five kinds of polyamide, polyacetyl, polycarbonate, polyester resin, and modified polyphenylene oxide. These are polymers ranging from tens to millions of polymers, unlike conventional plastics with molecular weights ranging from tens to hundreds of hundreds of molecules.

The engineering plastics that can be used in this embodiment are polyacetal (POM, Polyacetal PolyOxyMethylene), polyphenylene oxide (PPO, PolyPhehyleneoxide), polyamide (PI), polycarbonate (PC), polybutylene terephthalate (PBT, Polybuthylene Terephthlate), Polyarylate, Polysulfone (PSF, Polysulfone, Polysulphone), Polyphenylene sulfide (PPS, Polyphenylene sulfide), Polyetherimide (PEI, Polyether Imide), Polyether sulfone (PES) , PolyetherSulfon), Polyetheretherketone (PEEK, PolyEtherKetone), Ethylene Tetrafluoroethylene (PTFE, PolyTetraFluoroEthylene), Polychlorotrifluoroethylene (PCTFE, PolychlorotriFluoroEthylene) Perfluoroalkoxy (PFA), Polyethylene terephthalate (PET), High molecular weight polyethylene (UHMW-PE, Ultra high molecular weight polyethylene), polyvinylidenfluorid (PVDF), acrylonitrile butadiene styrene copolymer (ABS, Acrylonitryl Butadiene Styrene), nylon 6 (PA6, PA66), cerazole (PBI) , PolyBenzimidazole), polyurethane (Poly Urethane) and polyamideimide (PolyAmideImide) is at least one selected from the group consisting of.

For example, the plate-type reducer according to the present embodiment may be manufactured using only one material selected from the group of engineering plastics, and most preferably, polyether ether ketone (PEEK).

In addition, the plate reducer may be manufactured by mixing at least two materials selected from the above-mentioned engineering plastics group. In addition, it may further include a reinforcing agent contained in the engineering plastics to increase the strength of the member made of the engineering plastics. The reinforcing agent is any one of carbon fiber, glass fiber, and inorganic filler. The inorganic filler may include a ceramic.

In the case of manufacturing the plate reducer of the present embodiment from the engineering plastics (or the engineering plastics added with the reinforcing agent) as described above, it can be manufactured by injection molding instead of processing, thereby reducing manufacturing cost, preventing processing defects, and mass production in a short time. It can enjoy the positive effect of.

The above-described embodiments are merely illustrative, and various modifications and equivalent other embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of protection of the present invention should be determined by the technical idea of the invention described in the following claims.

10, 15: input shaft 20: rolling element
21: first motor body 25: second motor body
50: housing 100: operating part
110: input bearing 120: operating plate
115: movable body 200: output unit
210: first carrier 220: second carrier
230: carrier pin

Claims (17)

In the plate type reducer,
An input shaft driven to rotate by power provided from a drive source;
The plate surface is installed on the input shaft such that the plate surface is inclined with respect to the plane perpendicular to the rotation axis of the input shaft at a predetermined position of the input shaft, the plate surface is reciprocated meandering with respect to the rotation axis direction of the input shaft in conjunction with the rotation of the input shaft An actuating unit;
A rolling element movable by the operation unit in a direction of the rotation axis of the input shaft;
An output unit having a rotation guide groove formed on a surface opposing the rolling element, and being rotated by a pressing force of the rolling element;
And a housing having a guide groove for guiding the rolling element to move in an axial direction of the input shaft.
The operating unit includes an input bearing installed on the input shaft; It is installed to be rotatable relative to the input bearing, and includes a working plate for pressing the rolling element in the direction of the output,
The input bearing includes: an input inner ring having an insertion hole formed to be inserted into the input shaft and having a ball seat formed at an outer surface thereof; An input outer ring inserted into the hollow of the operation plate and having a ball seat formed therein; And a movable body installed in the ball seat of each of the input inner ring and the input outer ring to enable rolling motion. delete delete The method of claim 1,
And said input outer ring is formed integrally with said operating plate. The method of claim 1,
And the insertion hole is formed in the input inner ring such that the central axis of the input inner ring insertion hole is inclined at a predetermined angle with respect to the axis of the input shaft. The method of claim 1,
And the ball seat is formed on the input inner ring such that the plate surface formed by the ball seat of the input inner ring is inclined at a predetermined angle with respect to a plane perpendicular to the rotation axis. The method of claim 1,
The outer circumferential surface on which the ball seat of the input inner ring is formed is formed in a round shape. The method of claim 1,
The rolling element is
And a first motor body and a second motor body provided on each of both sides of the operating plate. 9. The method of claim 8,
The output unit includes:
A first carrier having the first motor body therebetween and installed to face one side of the operation plate, the first carrier having a first rotation guide groove formed on one surface of the operation plate opposite to the operation plate;
A second carrier having the second motor body interposed therebetween, the second carrier being provided opposite to the other side of the operation plate, and having a second rotation guide groove formed on one surface of the operation plate opposite to the operation plate;
And a carrier pin for coupling the first carrier and the second carrier so that the movement of the first carrier and the second carrier are interlocked with each other. 10. The method of claim 9,
Each of the first and second rotation guide grooves,
A plate-type reducer, characterized in that formed of at least one of a cycloid tooth, an involute tooth, and an arc tooth. 9. The method of claim 8,
The operating plate,
A first pressing piece for elastically pressing the first motor body in the first carrier direction;
And a second pressing piece spaced apart from the first pressing piece by a predetermined interval and elastically pressing the second electric body in the second carrier direction. 8. The method according to any one of claims 1 to 7,
And a support member interposed between the operation unit and the output unit and supporting the rolling element. 8. The method according to any one of claims 1 to 7,
The rolling element is
And at least one of a plurality of rigid balls and a plurality of rigid needles. 8. The method according to any one of claims 1 to 7,
The input shaft is a plate-type reducer, characterized in that formed in a hollow cylindrical shape. 8. The method according to any one of claims 1 to 7,
A first bearing interposed between the input shaft and the output unit to support the output unit to be independently rotated with respect to the input shaft;
And a second bearing interposed between the output unit and the housing to support the second unit to rotate relative to the output unit and the housing. 8. The method according to any one of claims 1 to 7,
And at least one of the input shaft, the operation unit, the rolling element, the output unit, and the housing is made of an engineering plastic material. 17. The method of claim 16,
The engineering plastics,
Polyacetal, polyphenylene oxide, polyamide, polycarbonate, polybutylene terephthalate, U polymer, polysulfone, polyphenylene sulfide, polyetherimide, polyether sulfone, polyarylate, polyether ether ketone, tetrafluoride Ethylene resin, polychlorotrifluoroethylene, chlorochlorofluoroethylene ethylene copolymer, perfluoroalkoxy, polyethylene terephthalate, high density molecular weight polyethylene, polyvinylidene fluoride, acrylonitrile butadiene styrene copolymer, nylon 6, cera A plate-type reducer, characterized in that at least any one selected from the group consisting of sol, polyurethane and polyamideimide.

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