Self-lubricating gear reducer

Abstract

The present application provides a self-lubricating gear reducer, which includes a box body, an output shaft and an input shaft. A small gear and a large gear that mesh with each other are arranged inside the box body. The small gear is sleeved on the input shaft, and the large gear is sleeved on the output shaft. The self-lubricating gear reducer further includes a hollow shaft joint. A lubricating gear is sleeved on the hollow shaft joint. The lubricating gear meshes with the small gear or the large gear. The lubricating gear is arranged above the small gear or the large gear. Hollow tubes are respectively arranged at both ends of the hollow shaft joint. The hollow shaft joint and the hollow tubes form an outer tube body. The hollow tube is provided with an inner conical surface, the inner wall of the hollow shaft joint is provided with an arc-shaped cavity, and a plurality of through holes are arranged along the circumferential direction of the hollow shaft joint, solving the problems that impurities in the traditional self-lubricating reducer repeatedly participate in lubrication and the running resistance increases due to excessive filling of grease.

Description

Technical Field

[0001] The present invention relates to the field of speed reducers, and particularly to a self-lubricating gear speed reducer. Background Art

[0002] A speed reducer is a transmission component, generally used to reduce the rotational speed of the power end and increase the torque. Among them, the common one is the box-type gear speed reducer, and the lubrication of the box-type gear speed reducer generally uses lubricating oil or grease.

[0003] When the gear speed reducer meshes, the two teeth rub against each other or cause relatively uniform wear, especially for a newly installed speed reducer that has not been run-in. Due to the presence of lubricating grease, the fine particles worn off generally adhere to the grease and are thrown out as the gears rotate, accumulating at the lower end of the box body.

[0004] For traditional self-lubricating speed reducers, mainly by adding a certain height of lubricating oil at the lower end of the box body or coating an excessive amount of grease on the gear surface. The former will cause the fine particles worn off to repeatedly participate in lubrication, resulting in a larger amount of wear, and the latter will cause too large a running resistance during the meshing process of the gears. Summary of the Invention

[0005] The present invention provides a self-lubricating gear speed reducer, which solves the problems of the traditional self-lubricating speed reducer that impurities repeatedly participate in lubrication and the running resistance increases due to excessive addition of grease.

[0006] To solve the above technical problems, the technical solution adopted by the present invention is: a self-lubricating gear speed reducer, including a box body, an output shaft and an input shaft. A small gear and a large gear that mesh with each other are arranged in the box body. The small gear is sleeved on the input shaft, and the large gear is sleeved on the output shaft. It also includes a hollow shaft joint, on which a lubricating gear is sleeved. The lubricating gear meshes with the small gear or the large gear, and the lubricating gear is arranged above the small gear or the large gear. Hollow tubes are respectively arranged at both ends of the hollow shaft joint. The hollow shaft joint and the hollow tubes form an outer tube body. The hollow tube is provided with an inner conical surface, the inner wall of the hollow shaft joint is provided with an arc-shaped cavity, and a plurality of through holes are arranged along the circumferential direction of the hollow shaft joint.

[0007] In a preferred solution, a detachable inner tube is sleeved inside the outer tube body, and a plurality of oil seepage channels are arranged along the circumferential direction of the inner tube.

[0008] In a preferred solution, a first end cover and a second end cover are respectively arranged at both ends of the inner tube, and the second end cover is provided with a central hole.

[0009] In a preferred embodiment, the through hole is a stepped hole, which includes a small hole portion and a large hole portion. A slidable movable oil-sealing terminal is provided in the through hole. The movable oil-sealing terminal is provided with a plugging head for plugging the small hole portion of the through hole. A magnetic ring piece is provided at one end of the movable oil-sealing terminal close to the plugging head, and the magnetic ring piece adsorbs the stepped end face of the large hole portion of the through hole. A plurality of oil grooves are provided on the outer wall of the movable oil-sealing terminal along the circumferential direction.

[0010] In a preferred embodiment, an adsorption column is provided inside the inner tube, and the adsorption column is a multi-porous and fluffy structure.

[0011] In a preferred embodiment, a counterbore is provided at the center of the adsorption column, and the counterbore communicates with the central hole. A conveying device is further provided, which includes an oil storage cylinder and a conveying oil pipe. One end of the conveying oil pipe is inserted into the central counterbore of the adsorption column through the central hole, and the other end of the conveying oil pipe communicates with the inside of the oil storage cylinder. A plurality of cutting grooves are provided along the circumferential direction of the central hole.

[0012] In a preferred embodiment, a guide block is further provided. A piston rod is slidably sleeved inside the guide block. A blind hole is provided inside the piston rod. One end of the blind hole communicates with the conveying oil pipe, and an oil inlet hole is provided on the side wall of the blind hole. A movable plate is slidably provided inside the oil storage cylinder. The movable plate is provided with a first spring to continuously extrude the lubricating grease inside the oil storage cylinder. The guide block is provided with an intermediate inlet hole, which communicates with the oil storage cylinder, and the communication state between the intermediate inlet hole and the oil inlet hole can be switched.

[0013] In a preferred embodiment, a fixing block is provided on one side of the guide block away from the conveying oil pipe. The fixing block is provided with an air cavity, and the air cavity is provided with an air inlet and exhaust port. One end of the piston rod is slidably sleeved with the air cavity, and a second spring is sleeved outside the piston rod. The two ends of the second spring respectively abut against the guide block and the piston rod.

[0014] In a preferred embodiment, one end of the conveying oil pipe away from the piston rod is closed, and a plurality of seepage holes are provided on the side wall of the conveying oil pipe.

[0015] In a preferred embodiment, the oil seepage channel is strip-shaped, circular hole-shaped or oval hole-shaped.

[0016] The beneficial effects of the present invention are as follows: The lubricating oil is conveyed in a meshing manner by using a hollow shaft and a lubricating gear with multiple sparse holes, so that the lubrication is more uniform, and the problem of increased running resistance caused by excessive lubricating grease is avoided; The lubricating structure can be placed above the running transmission gear, and the dirty lubricating oil dripping downward will not contaminate the lubricating gear, and the newly conveyed lubricating grease always remains clean, improving the lubrication effect; It is convenient to convey the lubricating grease online, and it is not necessary to stop the machine to operate when adding new lubricating grease and replacing dirty grease; In the preferred embodiment, the movable oil-sealing terminal has a throttling and pressure maintaining function, which can avoid the lubricating grease from gushing out and dripping due to excessive pressure of the oil filling machine when replenishing the lubricating oil, causing unnecessary waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0018] Figure 1 is a schematic diagram of the present invention.

[0019] Figure 2 is an internal layout diagram of the present invention.

[0020] Figure 3 is a cross-sectional view of the present invention.

[0021] Figure 4 is a cross-sectional view of the optimized structure of the present invention.

[0022] Figure 5 is a schematic diagram of the inner tube of the present invention.

[0023] Figure 6 is a partially enlarged view of the inner tube of the present invention.

[0024] Figure 7 is a schematic diagram of the movable oil-sealing terminal of the present invention.

[0025] Figure 8 is a schematic diagram of the second end cap of the present invention.

[0026] Figure 9 is a schematic diagram of the optimized expansion of the present invention.

[0027] Figure 10 is a schematic diagram of the grease conveying device of the present invention.

[0028] In the figure: hollow tube body 1; inner conical surface 101; inner tube 2; oil seepage channel 201; hollow shaft joint 3; through hole 301; arc-shaped cavity 302; movable oil-sealing terminal 303; plugging head 304; magnetic ring piece 305; oil passing groove 306; first end cap 4; second end cap 5; central hole 501; cut groove 502; adsorption column body 6; lubricating gear 7; pinion 8; large gear 9; box body 10; sedimentation tank 1001; oil drain hole 1002; oil guiding inclined surface 1003; output shaft 11; input shaft 12; conveying device 13; oil storage cylinder 1301; movable plate 1302; first spring 1303; piston rod 1304; oil inlet hole 1305; second spring 1306; conveying oil pipe 14; seepage hole 1401; guiding block 15; intermediate oil inlet hole 1501; fixing block 16; air cavity 1601. Specific embodiments

[0029] Such as Figures 1-10In it, a self-lubricating gear reducer includes a hollow shaft section 3, on which a lubricating gear 7 is sleeved. At both ends of the hollow shaft section 3, a hollow tube body 1 is provided respectively. The hollow shaft section 3 and the hollow tube body 1 form an outer tube body, and an inner tube 2 is sleeved inside the outer tube body. The inner tube 2 is provided with a plurality of oil seepage channels 201 along the circumferential direction. The hollow tube body 1 is provided with an inner conical surface 101, and the hollow shaft section 3 is provided with a plurality of through holes 301 along the circumferential direction.

[0030] The oil seepage channels 201 are strip-shaped through grooves or circular fine holes. The large-diameter end of the inner conical surface 101 is close to the hollow shaft section 3. Therefore, a gap that is large in the middle and small at both ends is formed between the outer wall of the inner tube 2 and the outer tube body. Lubricating oil or grease is stored inside the inner tube 2. When the entire shaft body rotates, the outer tube body and the inner tube 2 rotate synchronously. The stored grease penetrates into the gap between the inner tube 2 and the outer tube body through the oil seepage channels 201 under the action of centrifugal force. Since the inner conical surface 101 is conical, during the rotation process, the grease converges towards the middle under the action of centrifugal force, and then is dispersed into the lubricating gear 7 through the through holes 301.

[0031] By replacing the inner tube 2 with different oil seepage channels 201, the conveying rate of different lubricating greases can be controlled. For example, for the case where the rotational speed of the input shaft 12 is relatively large, the inner tube 2 with a smaller oil seepage channel 201 can be replaced. If the rotational speed of the input shaft 12 is relatively low, the inner tube 2 with a larger oil seepage channel 201 can be replaced.

[0032] The reducer is provided with a small gear 8 and a large gear 9. The small gear 8 is provided with an input shaft 12, and the large gear 9 is provided with an output shaft 11. The lubricating gear 7, the small gear 8, and the large gear 9 are all arranged inside the box body 10.

[0033] The lubricating gear 7 is made of felt material, which can evenly disperse the lubricating grease. The lubricating gear 7 meshes with the small gear 8, and evenly coats the tooth surface of the small gear 8 with lubrication. The small gear 8 meshes with the large gear 9, and then transfers the grease to the meshing large gear 9. The lubricating gear 7 is located above the small gear 8 in the box body 10. Most of the wear fine particles generated during the meshing process of the large gear 9 and the small gear 8 are centrifugally thrown out along with the lubricating grease and flow to the sedimentation tank 1001 along the inner wall of the box body 10 and the oil guiding inclined surface 1003 for accumulation. The lubricating oil seeping out from the lubricating gear 7 is always clean lubricating oil. A transparent observation window can be provided on the side wall of the box body 10 at the sedimentation tank 1001. When it is observed that the dirty grease accumulated in the sedimentation tank 1001 is almost close to the lower end of the large gear 9, the oil drain hole 1002 is opened to discharge the dirty grease.

[0034] Due to the difficult processing of the structure of the outer tube body that is small at both ends and large in the middle, in order to reduce the manufacturing process, the outer tube body is divided into three parts, namely the hollow shaft section 3 and the hollow tube bodies 1 at both ends, and a sealing ring is installed at the joint for sealing. One end of the hollow shaft section 3 is provided with a shaft shoulder. After the lubricating gear 7 is sleeved on the outer side surface of the hollow shaft section 3, the other end is locked by a threaded ring retainer.

[0035] In a preferred embodiment, a first end cap 4 and a second end cap 5 are respectively provided at both ends of the inner tube 2. The second end cap 5 is provided with a central hole 501, and a plurality of cutting grooves 502 are provided along the circumferential direction of the central hole 501.

[0036] The second end cap 5 can be made of rubber material, and lubricating oil and grease are supplemented into the inner tube 2 through the central hole 501 by an oil delivery pipe. The cutting grooves 502 can improve the deformation ability of the orifice of the central hole 501.

[0037] The oil delivery pipe can ensure the state of being inserted into the central hole 501 without being withdrawn. Due to the presence of the lubricating medium and the loose fit between the central hole 501 and the delivery pipe, even when rotating, it will not cause a large frictional resistance, which is convenient for on-line replenishment of lubricating grease during rotation.

[0038] Due to the high viscosity of the lubricating oil and grease and the narrow cutting grooves 502, it is difficult for the grease to naturally seep out from the cutting grooves 502. When the shaft body rotates rapidly, the grease concentrates on the inner wall of the inner tube 2, forming a cavity in the middle. The cutting grooves 502 are short, and the grease avoids the position of the cutting grooves 502.

[0039] In a preferred embodiment, an adsorption column 6 is provided inside the inner tube 2. The adsorption column 6 has a porous and fluffy structure.

[0040] The adsorption column 6 can be made of sponge material, which plays a good role in adsorbing and retaining lubricating grease or lubricating oil with low viscosity.

[0041] If the adsorption column 6 is directly installed in the outer tube body, due to the special internal shape of the outer tube body, the manufacturing and installation of the adsorption column 6 are both difficult, and the fitting tightness is not good. Since the inner tube 2 is an equal-diameter hollow tube, the adsorption column 6 is in the shape of an equal-diameter cylinder and does not require special processing technology. During installation, it is also in a relatively uniform contact state in the length direction; and the presence of the inner tube 2 forms a gap area that is large in the middle and small at both ends with the outer tube body. In the presence of the adsorption column 6, the grease first enters the gap area and then axially converges to the middle without being blocked by the body of the adsorption column 6, making the oil output smoother.

[0042] In a preferred embodiment, the through hole 301 is a stepped hole. The through hole 301 includes a small hole part and a large hole part. An axially slidable movable oil-sealing terminal 303 is provided in the through hole 301. The movable oil-sealing terminal 303 is provided with a plugging head 304. The plugging head 304 is used to plug the small hole part of the through hole 301. A magnetic ring piece 305 is provided at one end of the movable oil-sealing terminal 303 close to the plugging head 304. The magnetic ring piece 305 adsorbs the stepped end face of the large hole part of the through hole 301. A plurality of oil passing grooves 306 are provided along the circumferential direction of the outer wall of the movable oil-sealing terminal 303.

[0043] When the shaft body is stationary, under the adsorption of the magnetic ring piece 305, the movable oil-sealing terminal 303 closes the through-hole 301. At this time, the grease that has been transported to the lubricating gear 7 will not fall back to the inside of the outer tube body due to gravity, and the grease in the outer tube body will not continue to penetrate downward due to gravity. That is, when lubrication is not required during stationary, the lubrication process can be automatically terminated to avoid waste of lubricating grease.

[0044] In addition, since the through-hole 301 is closed, when grease is transported at this time, the outer tube body can maintain a certain pressure. When the grease in the outer tube body accumulates to a certain extent and the pressure reaches a certain value, the movable oil-sealing terminal 303 at the lower end cannot maintain adsorption due to magnetic force and then opens to maintain the internal and external pressure balance. However, due to the throttling effect of the oil passage 306 on the through-hole 301, it is avoided that the grease directly rushes out of the through-hole 301 under high pressure. When the grease continues to accumulate, all the movable oil-sealing terminals 303 open, but at this time the grease replenishment process is almost over, so a large amount of grease will not ooze and drip.

[0045] The adsorption force of the magnetic ring piece 305 is limited and only maintains the self-weight of the movable oil-sealing terminal 303. When the shaft body rotates, the magnetic ring piece 305 disengages from the stepped end face of the large-hole part of the through-hole 301. At this time, the movable oil-sealing terminal 303 moves outward, and the plugging head 304 can no longer plug the small-hole part of the through-hole 301. The lubricating grease in the outer tube body first enters the small-hole part of the through-hole 301 and then flows to the inner wall of the lubricating gear 7 through the oil passage 306. And since there are multiple oil passages 306, it can play a role in dispersing the grease.

[0046] In a preferred solution, an arc-shaped concave cavity 302 is provided on the inner wall of the hollow shaft joint 3.

[0047] The arc-shaped inner concave surface cooperates with the inner conical surface 101 of the hollow tube body 1 to effectively gather the grease to the middle part area where the through-holes 301 are distributed on the inner wall of the hollow shaft joint 3 when the shaft body rotates.

[0048] In a preferred solution, a counterbore is provided in the center of the adsorption cylinder 6, the counterbore is communicated with the central hole 501, and a conveying device 13 is further provided. The conveying device 13 includes an oil storage cylinder 1301 and a conveying oil pipe 14. One end of the conveying oil pipe 14 is inserted into the central counterbore of the adsorption cylinder 6 through the central hole 501, and the other end of the conveying oil pipe 14 is communicated with the inside of the oil storage cylinder 1301. A plurality of cutting grooves 502 are provided along the circumferential direction of the central hole 501.

[0049] In a preferred embodiment, a guiding block 15 is further provided. A piston rod 1304 is slidably sleeved inside the guiding block 15. A blind hole is provided inside the piston rod 1304. One end of the blind hole communicates with the delivery oil pipe 14, and an oil inlet hole 1305 is provided on the side wall of the blind hole. A movable plate 1302 is slidably provided inside the oil storage cylinder 1301. A first spring 1303 is provided on the movable plate 1302 to continuously extrude the lubricating grease inside the oil storage cylinder 1301. The guiding block 15 is provided with an intermediate inlet hole 1501, and the intermediate inlet hole 1501 communicates with the oil storage cylinder 1301. The communication state between the intermediate inlet hole 1501 and the oil inlet hole 1305 can be switched.

[0050] The oil storage cylinder 1301 is provided with a cover. Two ends of the first spring 1303 respectively abut against the cover and the movable plate 1302. The grease inside the oil storage cylinder 1301 maintains a continuous delivery pressure. Since the piston rod 1304 can slide horizontally, when it is necessary to replenish grease into the shaft body, the piston rod 1304 can be slid to make the intermediate inlet hole 1501 communicate with the oil inlet hole 1305. After the replenishment is completed, the piston rod 1304 is slid to stagger the intermediate inlet hole 1501 and the oil inlet hole 1305 to close the channel.

[0051] In a preferred embodiment, a fixing block 16 is provided on the side of the guiding block 15 away from the delivery oil pipe 14. The fixing block 16 is provided with an air cavity 1601. The air cavity 1601 is provided with an air inlet and outlet. One end of the piston rod 1304 is slidably sleeved with the air cavity 1601. A second spring 1306 is sleeved outside the piston rod 1304. Two ends of the second spring 1306 respectively abut against the guiding block 15 and the piston rod 1304.

[0052] The diameter of the contact part between the piston rod 1304 and the air cavity 1601 is large, and the second spring 1306 can abut against this part to continuously apply a thrust. The external valve body controls the air inlet and outlet of the air cavity 1601 to ventilate or pulse ventilate, and pushes the piston rod 1304 to make the intermediate inlet hole 1501 communicate with the oil inlet hole 1305.

[0053] In a preferred embodiment, one end of the delivery oil pipe 14 away from the piston rod 1304 is closed, and a plurality of seepage holes 1401 are provided on the side wall of the delivery oil pipe 14.

[0054] Through the seepage holes 1401, each part of the adsorption column body 6 can be evenly replenished with grease.

[0055] In a preferred embodiment, the oil seepage channel 201 is strip-shaped, round hole-shaped or oval hole-shaped.

[0056] The above embodiments are only the preferred technical solutions of the present invention and should not be regarded as limitations on the present invention. The protection scope of the present invention should be the technical solutions recorded in the claims, including the equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, the equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A self-lubricating gear reducer, characterized in that: It includes a box body (10), an output shaft (11) and an input shaft (12). Inside the box body (10), there are a small gear (8) and a large gear (9) that mesh with each other. The small gear (8) is sleeved on the input shaft (12), and the large gear (9) is sleeved on the output shaft (11). It also includes a hollow shaft joint (3). A lubricating gear (7) is sleeved on the hollow shaft joint (3). The lubricating gear (7) meshes with the small gear (8) or the large gear (9). The lubricating gear (7) is arranged above the small gear (8) or the large gear (9). At both ends of the hollow shaft joint (3), there are hollow tubes (1) respectively. The hollow shaft joint (3) and the hollow tubes (1) form an outer tube body. The hollow tube (1) is provided with an inner conical surface (101). The inner wall of the hollow shaft joint (3) is provided with an arc-shaped cavity (302). The hollow shaft joint (3) is provided with a plurality of through holes (301) along the circumferential direction; A detachable inner tube (2) is sleeved inside the outer tube body. The inner tube (2) is provided with a plurality of oil seepage channels (201) along the circumferential direction; The large diameter end of the inner conical surface (101) is close to the hollow shaft joint (3). Therefore, a gap that is large in the middle and small at both ends is formed between the outer wall of the inner tube (2) and the outer tube body. Lubricating oil or grease is stored inside the inner tube (2). When the entire shaft body rotates, the outer tube body and the inner tube (2) rotate synchronously. The grease stored inside seeps into the gap between the inner tube (2) and the outer tube body through the oil seepage channels (201) under the action of centrifugal force. Since the inner conical surface (101) is conical, during the rotation process, the grease converges towards the middle under the action of centrifugal force, and then is dispersed into the lubricating gear (7) through the through holes (301); At both ends of the inner tube (2), there are a first end cap (4) and a second end cap (5) respectively. The second end cap (5) is provided with a central hole (501); The through hole (301) is a stepped hole. The through hole (301) includes a small hole part and a large hole part. A slidable movable oil-sealing terminal (303) is arranged inside the through hole (301). The movable oil-sealing terminal (303) is provided with a plugging head (304). The plugging head (304) is used to plug the small hole part of the through hole (301). One end of the movable oil-sealing terminal (303) close to the plugging head (304) is provided with a magnetic ring piece (305). The magnetic ring piece (305) adsorbs the stepped end face of the large hole part of the through hole (301). A plurality of oil passing grooves (306) are arranged on the outer wall of the movable oil-sealing terminal (303) along the circumferential direction; When the shaft body is stationary, under the adsorption of the magnetic ring piece (305), the movable oil-sealing terminal (303) closes the through hole (301). When the shaft body rotates, the magnetic ring piece (305) disengages from the stepped end face of the large hole part of the through hole (301). At this time, the movable oil-sealing terminal (303) moves outwards, and the plugging head (304) can no longer plug the small hole part of the through hole (301). The lubricating grease inside the outer tube body enters the small hole part of the through hole (301), and then flows to the inner wall of the lubricating gear (7) through the oil passing grooves (306).

2. The self-lubricating gear reducer according to claim 1, wherein: An adsorption column body (6) is arranged inside the inner tube (2). The adsorption column body (6) is a multi-porous and fluffy structure.

3. The self-lubricating gear reducer according to claim 2, characterized in that: A sunken hole is provided at the center of the adsorption cylinder (6), and the sunken hole communicates with the central hole (501). A conveying device (13) is also provided. The conveying device (13) includes an oil storage cylinder (1301) and a conveying oil pipe (14). One end of the conveying oil pipe (14) is inserted into the central sunken hole of the adsorption cylinder (6) through the central hole (501), and the other end of the conveying oil pipe (14) communicates with the inside of the oil storage cylinder (1301). A plurality of cutting grooves (502) are provided along the circumferential direction of the central hole (501).

4. The self-lubricating gear reducer according to claim 3, characterized in that: A guide block (15) is also provided. A piston rod (1304) is slidably sleeved inside the guide block (15). A blind hole is provided inside the piston rod (1304). One end of the blind hole communicates with the conveying oil pipe (14), and an oil inlet hole (1305) is provided on the side wall of the blind hole. A movable plate (1302) that can slide is provided inside the oil storage cylinder (1301). The movable plate (1302) is provided with a first spring (1303) to continuously extrude the lubricating grease inside the oil storage cylinder (1301). The guide block (15) is provided with an intermediate inlet hole (1501), and the intermediate inlet hole (1501) communicates with the oil storage cylinder (1301). The communication state between the intermediate inlet hole (1501) and the oil inlet hole (1305) can be switched.

5. The self-lubricating gear reducer according to claim 4, wherein: A fixed block (16) is provided on the side of the guide block (15) away from the conveying oil pipe (14). The fixed block (16) is provided with an air cavity (1601). The air cavity (1601) is provided with an air inlet and exhaust port. One end of the piston rod (1304) is slidably sleeved with the air cavity (1601). A second spring (1306) is sleeved outside the piston rod (1304). The two ends of the second spring (1306) respectively abut against the guide block (15) and the piston rod (1304).

6. The self-lubricating gear reducer according to claim 5, characterized in that: One end of the conveying oil pipe (14) away from the piston rod (1304) is closed, and a plurality of seepage holes (1401) are provided on the side wall of the conveying oil pipe (14).

7. The self-lubricating gear reducer according to claim 1, characterized in that: The oil seepage channel (201) is strip-shaped, circular hole-shaped or elliptical hole-shaped.

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