CN210715360U

CN210715360U - Dustproof unloading device for cylinder cover

Info

Publication number: CN210715360U
Application number: CN201921180086.5U
Authority: CN
Inventors: 张泽栋; 江行舟; 白金文
Original assignee: BEIJING JINZI TIANCHENG HYDRAULIC TECHNOLOGY CO LTD
Current assignee: BEIJING JINZI TIANCHENG HYDRAULIC TECHNOLOGY CO LTD
Priority date: 2019-07-24
Filing date: 2019-07-24
Publication date: 2020-06-09
Anticipated expiration: 2029-07-24

Abstract

The utility model discloses a cylinder cap is with dustproof off-load device, this device install in the lateral surface of pneumatic cylinder cap, locate the one end of off-load oil circuit, including off-load valve overcoat, off-load valve endotheca, off-load case and compression spring. The unloading valve outer sleeve is connected with the inner wall of the unloading oil path, the unloading valve inner sleeve is arranged in the unloading valve outer sleeve, the unloading valve core is arranged in the unloading valve inner sleeve, the compression spring is arranged on the outer side of the unloading valve core in a sleeved mode, one end of the compression spring abuts against the unloading valve core, and the other end of the compression spring abuts against the unloading valve inner sleeve. The utility model provides a cylinder cap is with dustproof off-load device can enough be used for the hydraulic oil between discharge dust ring and the sealing washer, prevents that dust ring or sealing washer from damaging, can prevent again that outside pollutant from getting into, damages the pneumatic cylinder. The utility model discloses stable in structure safety can bear the hydraulic oil pressure in the off-load oil circuit, can guarantee the long-term steady operation of pneumatic cylinder.

Description

Dustproof unloading device for cylinder cover

Technical Field

The utility model relates to a heavy load pneumatic cylinder among the metallurgical industry reforms transform technical field, especially a dustproof unloading device is used to cylinder cap.

Background

The hydraulic cylinder used in the metallurgical industry is a large-specification heavy-load hydraulic cylinder generally, and the hydraulic cylinder is characterized in that the cylinder body is large in diameter, and the pressure and the impact load are large. The hydraulic cylinder is a hydraulic actuating element, converts hydraulic energy into mechanical energy, and realizes the linear reciprocating motion of the piston rod. Sealing device is the essential part of pneumatic cylinder, and the cylinder cap department of pneumatic cylinder all needs to set up dust ring and sealing washer, and wherein the effect of dust ring prevents that the outside pollutant of pneumatic cylinder from following the gap entering pneumatic cylinder when the piston rod is flexible, polluting the flexible environment of hydraulic stem. The sealing washer sets up in the inboard of dust ring, is closer to the cylinder of pneumatic cylinder, and the effect of sealing washer is the hydraulic oil of interception in the cylinder, prevents that hydraulic oil from revealing, influences the working property of pneumatic cylinder. In the metallurgical industry, the dust ring usually can choose for use the lip dust ring, and the lip dust ring can enough scrape the hydraulic oil of adhesion on the piston rod, can prevent that outside pollutant from getting into the pneumatic cylinder again. But the back is scraped to the hydraulic oil of adhesion on the piston rod, can pile up in the space between dust ring and sealing washer, makes the original pressureless appearance intracavity produce certain backpressure to hydraulic oil between dust ring and the sealing washer can be along with piston rod reciprocating motion's number of times increase and accumulate gradually, and the backpressure increases gradually, can destroy dust ring or sealing washer, leads to the pneumatic cylinder to damage.

At present, in order to solve the accumulational problem of hydraulic oil between dust ring and sealing washer, the method of taking is to set up a release hole that runs through the cylinder cap lateral wall between dust ring and sealing washer, accumulational fluid is discharged by the release hole, and set up a pneumatic muffler in the exit position of release hole, but pneumatic muffler itself can not bear the oil pressure, in case pressure is too big, the inside filter core of pneumatic muffler will damage, the filter core that damages loses the effect, outside pollutant can follow between release hole entering dust ring and the sealing washer, influence the reciprocating motion of piston rod, consequently, need to develop a neotype dust keeper, solve above-mentioned problem.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a dustproof unloading device is used to cylinder cap can discharge the hydraulic oil between dust ring and the sealing washer to prevent that outside pollutant from getting into the cylinder cap of pneumatic cylinder, guarantee that the pneumatic cylinder normally works.

In order to solve the technical problem, the utility model discloses a following technical scheme: a dustproof unloading device for a cylinder cover is installed on the outer side surface of a cylinder cover of a hydraulic cylinder and is arranged at one end of an unloading oil way. In order to prevent external pollutants from entering the hydraulic cylinder and intercept the leakage of hydraulic oil, the inner side surface of the cylinder cover is provided with a dustproof ring and a sealing ring, and the sealing ring is closer to the bottom of the cylinder than the dustproof ring. The unloading oil way is a through hole penetrating through the wall of the cylinder cover, one end of the unloading oil way is located in a gap between the dust ring and the sealing ring, and the other end of the unloading oil way is located on the outer side surface of the cylinder cover.

The dustproof unloading device for the cylinder cover comprises an unloading valve outer sleeve, an unloading valve inner sleeve, an unloading valve core and a compression spring. The unloading valve outer sleeve is connected with the unloading oil way, the unloading valve inner sleeve is arranged in the unloading valve outer sleeve, the unloading valve core is arranged in the unloading valve inner sleeve, the compression spring is arranged on the outer side of the unloading valve core in a sleeved mode, one end of the compression spring abuts against the unloading valve core, and the other end of the compression spring abuts against the unloading valve inner sleeve.

The unloading valve outer sleeve comprises a first connecting seat and a first threaded cylinder which are integrally formed and coaxially arranged, a circular inner threaded hole is formed in the middle of the first connecting seat, and the outer side of the first connecting seat is hexagonal. The first threaded cylinder is cylindrical, and the radial sectional area of the first threaded cylinder is smaller than that of the first connecting seat. The outer side of the first threaded cylinder is provided with an external thread, and the inner side of the unloading oil way is provided with an internal thread matched with the external thread on the outer side of the first threaded cylinder. A first reducing through hole is formed in the inner side of the first threaded cylinder, the diameter of one end, close to the first connecting seat, of the first reducing through hole is large, the diameter of one end, far away from the first connecting seat, of the first reducing through hole is small, the maximum diameter of the first reducing through hole is equal to the diameter of a round hole in the inner side of the first connecting seat, and the end, small in diameter, of the first reducing through hole is communicated with an unloading oil way.

The reducing part of the first reducing through hole is a circular truncated cone-shaped hole, the diameter of the circular truncated cone-shaped hole is uniformly changed, the diameter of the upper bottom surface of the circular truncated cone is equal to that of the end with the smaller diameter of the first reducing through hole, the diameter of the lower bottom surface of the circular truncated cone is equal to that of the end with the larger diameter of the first reducing through hole, and the included angle between the generatrix of the circular truncated cone and the upper bottom surface is 120-140 degrees.

A circle of mounting groove is formed in one side, close to the first threaded cylinder, of the first connecting seat, and a gasket is further laid in the mounting groove. A first thread cylinder of an unloading valve outer sleeve is screwed in an unloading oil way, and a first connecting seat is in contact with the outer side surface of a cylinder cover. The gasket is positioned between the dustproof unloading device and the outer side surface of the cylinder cover, and can play roles in gasket, sealing, buffering and shock absorption.

The unloading valve inner sleeve comprises a second connecting seat and a second threaded cylinder which are integrally formed and coaxially arranged, a circular through hole is formed in the middle of the second connecting seat, and the outer side of the second connecting seat is hexagonal. The second thread cylinder is cylindrical, and the radial sectional area of the second thread cylinder is smaller than that of the second connecting seat. The outer side of the second thread cylinder is provided with an external thread matched with the internal thread on the inner side of the first connecting seat, and the inner side of the second thread cylinder is provided with a second reducing through hole. The one end that the diameter of second reducing through-hole is little is close to the second connecting seat, and with the inboard round hole isodiametric of second connecting seat, the second connecting seat is kept away from to the one end that the diameter of second reducing through-hole is big.

The unloading valve core comprises a threaded rod, a straight rod and a movable head which are integrally formed, sequentially connected and coaxially arranged, the threaded rod and the straight rod are cylindrical, an external thread is formed in the outer side of the threaded rod, a straight groove is formed in one end, away from the straight rod, of the threaded rod, a locking nut is further sleeved on the outer side of the threaded rod, and the internal thread of the locking nut is matched with the external thread on the outer side of the threaded rod. One end of the movable head, which is far away from the straight rod, is in a round table shape, the upper bottom surface of the round table is far away from the straight rod, and the diameter of the upper bottom surface is smaller than the minimum diameter of the first reducing through hole; the lower bottom surface of the circular truncated cone is close to the straight rod, the diameter of the lower bottom surface is larger than the minimum diameter of the first reducing through hole, and the diameter of the lower bottom surface is smaller than the maximum diameter of the first reducing through hole. The included angle between the generatrix of the circular truncated cone and the upper bottom surface is 100-110 degrees.

The compression spring is a spiral spring, the outer diameter of the compression spring is smaller than the maximum diameter of the second reducing through hole and larger than the minimum diameter of the second reducing through hole, and the outer diameter of the compression spring is smaller than the maximum diameter of the circular truncated cone in the movable head.

The unloading valve outer sleeve, the unloading valve inner sleeve, the unloading valve core and the compression spring are coaxially arranged, a first thread cylinder in the unloading valve outer sleeve is screwed in an unloading oil way, a second thread cylinder in the unloading valve inner sleeve is screwed in a first connecting seat, a movable head in the unloading valve core is positioned in the first thread cylinder, a threaded rod in the unloading valve core is positioned on one side, away from the second thread cylinder, of the second connecting seat, one end of the compression spring abuts against the movable head, and the other end of the compression spring abuts against the reducing part of the second reducing through hole. The utility model discloses can be through adjusting the interval between a word groove control activity head and the first screw thread section of thick bamboo, and then control the discharge velocity of hydraulic oil, when the hydraulic oil in the off-load oil circuit is more, use spanner fixed lock nut, through a word groove adjustment off-load case, make the variable diameter department that first reducing through-hole was kept away from to the activity head, enlarge the interval, hydraulic oil discharge velocity accelerates.

The utility model discloses still include the gasket, the gasket is located between first connecting seat and the second connecting seat for the buffering shock attenuation.

The distance between the inner surface of the second connecting seat and the outer surface of the straight rod is 0.3mm-0.6 mm.

The movable head of the unloading valve core blocks the first variable-diameter through hole under the action of the compression spring, external pollutants cannot enter a cylinder cover of the hydraulic cylinder, and hydraulic oil scraped by the sealing ring is accumulated in the unloading oil way. The hydraulic oil in the unloading oil way is gradually accumulated, the pressure is increased, when the pressure in the unloading oil way exceeds the resistance in the compression spring, the movable head of the unloading valve core can be jacked open, the hydraulic oil in the unloading oil way can be discharged along the gap between the inner sleeve of the unloading valve and the unloading valve core, and when the pressure in the unloading oil way is reduced, the movable head of the unloading valve core plugs the first reducing through hole again to isolate external pollutants.

Compared with the prior art, the utility model discloses an useful part lies in: the dustproof unloading device for the cylinder cover is arranged on the outer side surface of the cylinder cover of the hydraulic cylinder, can be used for discharging hydraulic oil between a dustproof ring and a sealing ring, prevents the dustproof ring or the sealing ring from being damaged, and can prevent external pollutants from entering and damaging the hydraulic cylinder. The utility model discloses stable in structure safety can bear the hydraulic oil pressure in the off-load oil circuit, can guarantee the long-term steady operation of pneumatic cylinder.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a cross-sectional view of the outer cover of the pressure relief valve of the present invention;

FIG. 3 is a cross-sectional view of the inner sleeve of the pressure relief valve of the present invention;

fig. 4 is a schematic structural view of a pressure relief valve element of the present invention;

fig. 5 is a schematic view of the installation position of the present invention;

fig. 6 is a radial side view of the present invention.

The meaning of the reference numerals: the hydraulic cylinder comprises a cylinder cover 1, an unloading oil way 2, an unloading valve outer sleeve 3, an unloading valve inner sleeve 4, an unloading valve core 5, a compression spring 6, a dustproof ring 7, a sealing ring 8, a first connecting seat 9, a first threaded cylinder 10, a first reducing through hole 11, an installation groove 12, a second connecting seat 13, a second threaded cylinder 14, a second reducing through hole 15, a threaded rod 16, a straight rod 17, a movable head 18, a straight groove 19, a locking nut 20 and a gasket 21.

The present invention will be further described with reference to the accompanying drawings and the detailed description.

Detailed Description

Embodiment 1 of the utility model: as shown in fig. 5, a dustproof unloading device for cylinder cover is installed in the lateral surface of hydraulic cylinder cover 1, locates the one end of off-load oil circuit 2, the medial surface of cylinder cover 1 is equipped with dust ring 7 and sealing washer 8, and dust ring 7 can be isolated with external pollutants in the one side that cylinder cover 1 keeps away from the cylinder bottom, and sealing washer 8 is close to the one side of cylinder bottom in cylinder cover 1, can scrape the hydraulic oil of adhesion on the piston rod down, prevents simultaneously that hydraulic oil from leaking. However, with repeated use of the hydraulic cylinder, hydraulic oil can be accumulated in a gap between the dust ring 7 and the sealing ring 8, so that one end of the unloading oil path 2 is located between the dust ring 7 and the sealing ring 8, and the other end of the unloading oil path 2 is located on the outer side surface of the cylinder cover 1 and used for discharging the hydraulic oil between the dust ring 7 and the sealing ring 8. The dustproof unloading device for the cylinder cover comprises an unloading valve outer sleeve 3, an unloading valve inner sleeve 4, an unloading valve core 5 and a compression spring 6, wherein the unloading valve outer sleeve 3, the unloading valve inner sleeve 4 and the unloading valve core 5 are all made of 2Cr13 (a type of martensitic stainless steel), and the influence of severe working environments in the metallurgical industry on the dustproof unloading device for the cylinder cover can be effectively resisted. In the embodiment, the inner side of the unloading oil way 2 is provided with an internal thread, so that the installation of the dustproof unloading device is facilitated.

As shown in fig. 2, the unloading valve housing 3 in the present embodiment includes a first connecting seat 9 and a first threaded cylinder 10 which are integrally formed and coaxially arranged. As shown in fig. 6, a circular female screw hole is opened in the middle of the first connecting seat 9, and the outer side of the first connecting seat 9 is hexagonal. The first threaded cylinder 10 is a circular through hole and is coaxially connected with the first connecting seat 9, and the radial sectional area of the first threaded cylinder 10 is smaller than that of the first connecting seat 9. The outer side of the first thread cylinder 10 is provided with an external thread matched with the internal thread on the inner side of the unloading oil way 2, and the first thread cylinder 10 is tightly connected with the unloading oil way 2 through a thread. A first reducing through hole 11 is formed in the inner side of the first threaded cylinder 10, the first reducing through hole 11 is close to the first connecting seat 9, and the diameter of the first reducing through hole is equal to that of a round hole in the inner side of the first connecting seat 9. The diameter of one end, far away from the first connecting seat 9, of the first reducing through hole 11 is small, the diameter of one end, close to the first connecting seat 9, of the first reducing through hole 11 is large, and the maximum diameter of the first reducing through hole 11 is equal to the diameter of the round hole in the inner side of the first connecting seat 9. The end with the smaller diameter of the first reducing through hole is communicated with the unloading oil way 2, and hydraulic oil in the unloading oil way 2 can enter the dustproof unloading device through the end with the smaller diameter of the first reducing through hole 11. In this embodiment, a circular truncated cone-shaped hole is formed between the end with the larger diameter of the first diameter-changing through hole 11 and the end with the smaller diameter, the hole diameter of the circular truncated cone-shaped hole is uniformly changed, the diameter of the upper bottom surface of the circular truncated cone is equal to that of the end with the smaller diameter of the first diameter-changing through hole 11, the diameter of the lower bottom surface of the circular truncated cone is equal to that of the end with the larger diameter of the first diameter-changing through hole 11, and the included angle between the bus.

As shown in fig. 3, the unloading valve inner sleeve 4 in this embodiment includes a second connecting seat 13 and a second threaded cylinder 14 that are integrally formed and connected in sequence, a circular through hole is opened in the middle of the second connecting seat 13, and the outer side of the second connecting seat 13 is hexagonal. The second threaded cylinder 14 is cylindrical, and the radial sectional area of the second threaded cylinder 14 is smaller than the radial sectional area of the second connecting seat 13. The outer side of the second thread cylinder 14 is provided with an external thread matched with the internal thread on the inner side of the first connecting seat 9, and the inner side of the second thread cylinder 14 is provided with a second reducing through hole 15. The end of the second reducing through hole 15 with a small diameter is close to the second connecting seat 13 and has the same diameter as the inner round hole of the second connecting seat 13. The end of the second reducing through hole 15 with a large diameter is far away from the second connecting seat 13. The second threaded cylinder 14 is threadedly connected with the first connecting seat 9, and the first threaded cylinder 10 and the second threaded cylinder 14 form a cavity in the dust-proof unloading device.

As shown in fig. 4, the unloading valve core 5 comprises a threaded rod 16, a straight rod 17 and a movable head 18 which are integrally formed, connected in sequence and coaxially arranged. The threaded rod 16 and the straight rod 17 are both cylindrical, an external thread is formed in the outer side of the threaded rod 16, a straight groove 19 is further formed in one end, away from the straight rod 17, of the threaded rod 16, a locking nut 20 is further sleeved on the outer side of the threaded rod 16, and the internal thread of the locking nut 20 is matched with the external thread on the outer side of the threaded rod 16. The end, far away from the straight rod 17, of the movable head 18 is in a circular truncated cone shape, the upper bottom surface of the circular truncated cone is far away from the straight rod 17, and the diameter of the upper bottom surface is smaller than the minimum diameter of the first reducing through hole 11. The lower bottom surface of the circular truncated cone is close to the straight rod 17, the diameter of the lower bottom surface is larger than the minimum diameter of the first variable diameter through hole 11, and the diameter of the lower bottom surface is smaller than the maximum diameter of the first variable diameter through hole 11. The included angle between the generatrix of the circular truncated cone and the upper bottom surface is 100 degrees.

In this embodiment, the compression spring 6 is a coil spring, the outer diameter of the compression spring 6 is smaller than the maximum diameter of the second reducing through hole 15 and larger than the minimum diameter of the second reducing through hole 15, and the outer diameter of the compression spring 6 is also smaller than the maximum diameter of the circular truncated cone in the movable head 18.

As shown in fig. 1, the unloading valve outer sleeve 3, the unloading valve inner sleeve 4, the unloading valve core 5 and the compression spring 6 are coaxially arranged, a first threaded cylinder 10 in the unloading valve outer sleeve 3 is screwed in the unloading oil path 2, a second threaded cylinder 14 in the unloading valve outer sleeve 4 is screwed in the first connecting seat 9, a movable head 18 in the unloading valve core 5 is located in a cavity formed by the first threaded cylinder 10 and the second threaded cylinder 14, and a gap is left between the straight rod 17 and the second connecting seat 13, wherein the distance is 0.4 mm. The threaded rod 16 in the unloading valve core 5 is positioned on one side, away from the second threaded cylinder 14, of the second connecting seat 13, one end of the compression spring 6 props against the movable head 18, and the other end of the compression spring 6 props against the reducing part of the second reducing through hole 15. The compression spring 6 is pressed, the movable head 18 is abutted against the end with the smaller diameter of the first reducing through hole 11 under the action of the compression spring 6, the unloading oil way 2 is sealed and blocked, and external pollutants cannot enter the cylinder cover 1 through the dustproof unloading device. The hydraulic oil in the unloading oil circuit 2 is gradually accumulated, the pressure is increased, the hydraulic oil can jack up the movable head 18, the compression spring 6 is further compressed, the hydraulic oil can be discharged along the gap between the straight rod 17 and the second connecting seat 13, the pressure in the unloading oil circuit 2 can be released, and the dust ring 7 and the sealing ring 8 are prevented from being damaged due to the fact that the pressure is increased. The discharging speed of the hydraulic oil can be adjusted, when the hydraulic oil in the unloading oil way 2 is too much, the straight groove 19 is adjusted by fixing the locking nut 20, the distance between the movable head 18 and the reducing part of the first reducing through hole 11 is increased, and the discharging speed of the hydraulic oil is further increased.

Embodiment 2 of the utility model: as shown in fig. 5, a dustproof unloading device for cylinder cover is installed in the lateral surface of hydraulic cylinder cover 1, locates the one end of off-load oil circuit 2, the medial surface of cylinder cover 1 is equipped with dust ring 7 and sealing washer 8, and dust ring 7 can be isolated with external pollutants in the one side that cylinder cover 1 keeps away from the cylinder bottom, and sealing washer 8 is close to the one side of cylinder bottom in cylinder cover 1, can scrape the hydraulic oil of adhesion on the piston rod down, prevents simultaneously that hydraulic oil from leaking. However, with repeated use of the hydraulic cylinder, hydraulic oil can be accumulated in a gap between the dust ring 7 and the sealing ring 8, so that one end of the unloading oil path 2 is located between the dust ring 7 and the sealing ring 8, and the other end of the unloading oil path 2 is located on the outer side surface of the cylinder cover 1 and used for discharging the hydraulic oil between the dust ring 7 and the sealing ring 8. The dustproof unloading device for the cylinder cover comprises an unloading valve outer sleeve 3, an unloading valve inner sleeve 4, an unloading valve core 5 and a compression spring 6, wherein the unloading valve outer sleeve 3, the unloading valve inner sleeve 4 and the unloading valve core 5 are all made of 2Cr13 (a type of martensitic stainless steel), and the influence of severe working environments in the metallurgical industry on the dustproof unloading device for the cylinder cover can be effectively resisted. In the embodiment, the inner side of the unloading oil way 2 is provided with an internal thread, so that the installation of the dustproof unloading device is facilitated.

As shown in fig. 4, the unloading valve core 5 comprises a threaded rod 16, a straight rod 17 and a movable head 18 which are integrally formed, connected in sequence and coaxially arranged. The threaded rod 16 and the straight rod 17 are both cylindrical, an external thread is formed in the outer side of the threaded rod 16, a straight groove 19 is further formed in one end, away from the straight rod 17, of the threaded rod 16, a locking nut 20 is further sleeved on the outer side of the threaded rod 16, and the internal thread of the locking nut 20 is matched with the external thread on the outer side of the threaded rod 16. The end, far away from the straight rod 17, of the movable head 18 is in a circular truncated cone shape, the upper bottom surface of the circular truncated cone is far away from the straight rod 17, and the diameter of the upper bottom surface is smaller than the minimum diameter of the first reducing through hole 11. The lower bottom surface of the circular truncated cone is close to the straight rod 17, the diameter of the lower bottom surface is larger than the minimum diameter of the first variable diameter through hole 11, and the diameter of the lower bottom surface is smaller than the maximum diameter of the first variable diameter through hole 11. The included angle between the generatrix of the circular truncated cone and the upper bottom surface is 105 degrees.

As shown in fig. 1, the unloading valve outer sleeve 3, the unloading valve inner sleeve 4, the unloading valve core 5 and the compression spring 6 are coaxially arranged, a first threaded cylinder 10 in the unloading valve outer sleeve 3 is screwed in the unloading oil path 2, a second threaded cylinder 14 in the unloading valve outer sleeve 4 is screwed in the first connecting seat 9, a movable head 18 in the unloading valve core 5 is located in a cavity formed by the first threaded cylinder 10 and the second threaded cylinder 14, and a gap is left between the straight rod 17 and the second connecting seat 13, wherein the distance is 0.6 mm. The threaded rod 16 in the unloading valve core 5 is positioned on one side, away from the second threaded cylinder 14, of the second connecting seat 13, one end of the compression spring 6 props against the movable head 18, and the other end of the compression spring 6 props against the reducing part of the second reducing through hole 15. The compression spring 6 is pressed, the movable head 18 is abutted against the end with the smaller diameter of the first reducing through hole 11 under the action of the compression spring 6, the unloading oil way 2 is sealed and blocked, and external pollutants cannot enter the cylinder cover 1 through the dustproof unloading device. The hydraulic oil in the unloading oil circuit 2 is gradually accumulated, the pressure is increased, the hydraulic oil can jack up the movable head 18, the compression spring 6 is further compressed, the hydraulic oil can be discharged along the gap between the straight rod 17 and the second connecting seat 13, the pressure in the unloading oil circuit 2 can be released, and the dust ring 7 and the sealing ring 8 are prevented from being damaged due to the fact that the pressure is increased. The discharging speed of the hydraulic oil can be adjusted, when the hydraulic oil in the unloading oil way 2 is too much, the straight groove 19 is adjusted by fixing the locking nut 20, the distance between the movable head 18 and the reducing part of the first reducing through hole 11 is increased, and the discharging speed of the hydraulic oil is further increased.

As shown in fig. 2, in the present embodiment, an installation groove 12 is further formed on one side of the first connection seat 9 close to the first threaded cylinder 10, and a gasket is disposed in the installation groove 12. As shown in fig. 5, the dust-proof unloading device for the cylinder cover is installed on the unloading oil path 2, the first connecting seat 9 is in contact with the side surface of the cylinder cover 1, and the additional installation groove 12 and the gasket can play roles of sealing, padding, buffering and shock absorption.

Embodiment 3 of the utility model: as shown in fig. 5, a dustproof unloading device for cylinder cover is installed in the lateral surface of hydraulic cylinder cover 1, locates the one end of off-load oil circuit 2, the medial surface of cylinder cover 1 is equipped with dust ring 7 and sealing washer 8, and dust ring 7 can be isolated with external pollutants in the one side that cylinder cover 1 keeps away from the cylinder bottom, and sealing washer 8 is close to the one side of cylinder bottom in cylinder cover 1, can scrape the hydraulic oil of adhesion on the piston rod down, prevents simultaneously that hydraulic oil from leaking. However, with repeated use of the hydraulic cylinder, hydraulic oil can be accumulated in a gap between the dust ring 7 and the sealing ring 8, so that one end of the unloading oil path 2 is located between the dust ring 7 and the sealing ring 8, and the other end of the unloading oil path 2 is located on the outer side surface of the cylinder cover 1 and used for discharging the hydraulic oil between the dust ring 7 and the sealing ring 8. The dustproof unloading device for the cylinder cover comprises an unloading valve outer sleeve 3, an unloading valve inner sleeve 4, an unloading valve core 5 and a compression spring 6, wherein the unloading valve outer sleeve 3, the unloading valve inner sleeve 4 and the unloading valve core 5 are all made of 2Cr13 (a type of martensitic stainless steel), and the influence of severe working environments in the metallurgical industry on the dustproof unloading device for the cylinder cover can be effectively resisted. In the embodiment, the inner side of the unloading oil way 2 is provided with an internal thread, so that the installation of the dustproof unloading device is facilitated.

As shown in fig. 4, the unloading valve core 5 comprises a threaded rod 16, a straight rod 17 and a movable head 18 which are integrally formed, connected in sequence and coaxially arranged. The threaded rod 16 and the straight rod 17 are both cylindrical, an external thread is formed in the outer side of the threaded rod 16, a straight groove 19 is further formed in one end, away from the straight rod 17, of the threaded rod 16, a locking nut 20 is further sleeved on the outer side of the threaded rod 16, and the internal thread of the locking nut 20 is matched with the external thread on the outer side of the threaded rod 16. The end, far away from the straight rod 17, of the movable head 18 is in a circular truncated cone shape, the upper bottom surface of the circular truncated cone is far away from the straight rod 17, and the diameter of the upper bottom surface is smaller than the minimum diameter of the first reducing through hole 11. The lower bottom surface of the circular truncated cone is close to the straight rod 17, the diameter of the lower bottom surface is larger than the minimum diameter of the first variable diameter through hole 11, and the diameter of the lower bottom surface is smaller than the maximum diameter of the first variable diameter through hole 11. The included angle between the generatrix of the circular truncated cone and the upper bottom surface is 110 degrees.

As shown in fig. 1, the unloading valve outer sleeve 3, the unloading valve inner sleeve 4, the unloading valve core 5 and the compression spring 6 are coaxially arranged, a first threaded cylinder 10 in the unloading valve outer sleeve 3 is screwed in the unloading oil path 2, a second threaded cylinder 14 in the unloading valve outer sleeve 4 is screwed in the first connecting seat 9, a movable head 18 in the unloading valve core 5 is located in a cavity formed by the first threaded cylinder 10 and the second threaded cylinder 14, and a gap is left between the straight rod 17 and the second connecting seat 13, wherein the distance is 0.3 mm. The threaded rod 16 in the unloading valve core 5 is positioned on one side, away from the second threaded cylinder 14, of the second connecting seat 13, one end of the compression spring 6 props against the movable head 18, and the other end of the compression spring 6 props against the reducing part of the second reducing through hole 15. The compression spring 6 is pressed, the movable head 18 is abutted against the end with the smaller diameter of the first reducing through hole 11 under the action of the compression spring 6, the unloading oil way 2 is sealed and blocked, and external pollutants cannot enter the cylinder cover 1 through the dustproof unloading device. The hydraulic oil in the unloading oil circuit 2 is gradually accumulated, the pressure is increased, the hydraulic oil can jack up the movable head 18, the compression spring 6 is further compressed, the hydraulic oil can be discharged along the gap between the straight rod 17 and the second connecting seat 13, the pressure in the unloading oil circuit 2 can be released, and the dust ring 7 and the sealing ring 8 are prevented from being damaged due to the fact that the pressure is increased. The discharging speed of the hydraulic oil can be adjusted, when the hydraulic oil in the unloading oil way 2 is too much, the straight groove 19 is adjusted by fixing the locking nut 20, the distance between the movable head 18 and the reducing part of the first reducing through hole 11 is increased, and the discharging speed of the hydraulic oil is further increased.

As shown in fig. 1, the present embodiment further includes a gasket 21, where the gasket 21 is located between the first connecting seat 9 and the second connecting seat 13 and is used as a buffer between the outer unloading valve sleeve 3 and the inner unloading valve sleeve 4, and the gasket is made of fluororubber in the present embodiment.

The utility model discloses a theory of operation: the inboard dust ring 7 and the sealing washer 8 that set up of cylinder cap 1 of pneumatic cylinder can accumulate hydraulic oil gradually between dust ring 7 and sealing washer 8. An unloading oil way 2 penetrates through the side surface of the hydraulic cylinder cover 1, one end of the unloading oil way 2 is positioned between the dust ring 7 and the sealing ring 8, and the other end of the unloading oil way 2 is positioned on the outer side surface of the cylinder cover 1. The utility model discloses install the port position in the 1 outside of cylinder cap in off-load oil circuit 2, hydraulic oil between dust ring 7 and the sealing washer 8 gets into off-load oil circuit 2, and by the utility model discloses the interception. Along with the gradual accumulation of the hydraulic oil in the unloading oil path 2, the pressure in the unloading oil path 2 also gradually increases, the unloading valve core 5 is jacked up, a gap is formed between the unloading valve core 5 and the first reducing through hole 11, and the hydraulic oil can be discharged out of the cylinder cover 1. After the unloading oil circuit 2 is used for the first time or is cleaned completely, no hydraulic oil is in the unloading oil circuit 2 or the pressure is low, the unloading valve core 5 is propped against the diameter-changing position of the first diameter-changing through hole 11 under the action of the compression spring 6, the first diameter-changing through hole 11 is sealed, external pollutants are isolated, and the dustproof effect is achieved.

Claims

1. The utility model provides a dustproof unloading device for cylinder cap installs in the lateral surface of pneumatic cylinder cap (1), locates the one end of off-load oil circuit (2), the medial surface of cylinder cap (1) is equipped with dust ring (7) and sealing washer (8), the one end of off-load oil circuit (2) is located between dust ring (7) and sealing washer (8), and the other end of off-load oil circuit (2) is located the lateral surface of cylinder cap (1), this dustproof unloading device for cylinder cap's characterized in that: comprises an outer unloading valve sleeve (3), an inner unloading valve sleeve (4), an unloading valve core (5) and a compression spring (6); the unloading valve is characterized in that the unloading valve outer sleeve (3) is connected with the unloading oil way (2), the unloading valve inner sleeve (4) is arranged in the unloading valve outer sleeve (3), the unloading valve core (5) is arranged in the unloading valve inner sleeve (4), the compression spring (6) is sleeved on the outer side of the unloading valve core (5), one end of the compression spring (6) is abutted against the unloading valve core (5), and the other end of the compression spring (6) is abutted against the unloading valve inner sleeve (4).

2. The dust-proof unloading device for the cylinder head according to claim 1, characterized in that: the unloading valve outer sleeve (3) comprises a first connecting seat (9) and a first threaded cylinder (10) which are integrally formed and coaxially arranged, a circular internal threaded hole is formed in the middle of the first connecting seat (9), and the outer side of the first connecting seat (9) is hexagonal; the first threaded cylinder (10) is cylindrical, the radial sectional area of the first threaded cylinder (10) is smaller than that of the first connecting seat (9), an external thread is arranged on the outer side of the first threaded cylinder (10), and an internal thread matched with the external thread on the outer side of the first threaded cylinder (10) is arranged on the inner side of the unloading oil path (2); first reducing through hole (11) have been seted up to the inboard of first thread section of thick bamboo (10), the diameter that first reducing through hole (11) is close to first connecting seat (9) one end is greater than the diameter that first connecting seat (9) one end was kept away from in first reducing through hole (11), and the maximum diameter of first reducing through hole (11) equals with the diameter of the inboard round hole of first connecting seat (9), the one end that first reducing through hole (11) diameter is little communicates with each other with off-load oil circuit (2).

3. The dust-proof unloading device for the cylinder head according to claim 2, characterized in that: the reducing part of the first reducing through hole (11) is a circular truncated cone-shaped hole, the diameter of the upper bottom surface of the circular truncated cone is equal to that of the end with the small diameter of the first reducing through hole (11), the diameter of the lower bottom surface of the circular truncated cone is equal to that of the end with the large diameter of the first reducing through hole (11), and the included angle between the generatrix of the circular truncated cone and the upper bottom surface is 120-140 degrees.

4. The dust-proof unloading device for the cylinder head according to claim 2, characterized in that: one side of the first connecting seat (9) close to the first threaded cylinder (10) is provided with a circle of mounting groove (12), and a gasket is further laid in the mounting groove (12).

5. The dust-proof unloading device for the cylinder head according to claim 3, characterized in that: the unloading valve inner sleeve (4) comprises a second connecting seat (13) and a second threaded cylinder (14) which are integrally formed and coaxially arranged, a circular through hole is formed in the middle of the second connecting seat (13), and the outer side of the second connecting seat (13) is hexagonal; the second threaded cylinder (14) is cylindrical, the radial sectional area of the second threaded cylinder (14) is smaller than that of the second connecting seat (13), and the outer side of the second threaded cylinder (14) is provided with an external thread matched with the internal thread on the inner side of the first connecting seat (9); a second reducing through hole (15) is formed in the inner side of the second threaded cylinder (14); the end, with the small diameter, of the second variable-diameter through hole (15) is close to the second connecting seat (13) and has the same diameter as the inner round hole of the second connecting seat (13); the end of the second reducing through hole (15) with large diameter is far away from the second connecting seat (13).

6. The dust-proof unloading device for the cylinder cover according to claim 5, characterized in that: the unloading valve core (5) comprises a threaded rod (16), a straight rod (17) and a movable head (18), wherein the threaded rod (16) and the straight rod (17) are integrally formed, connected in sequence and coaxially arranged, the threaded rod (16) and the straight rod (17) are both cylindrical, an external thread is arranged on the outer side of the threaded rod (16), a straight groove (19) is further formed in one end, away from the straight rod (17), of the threaded rod (16), a locking nut (20) is further sleeved on the outer side of the threaded rod (16), and an internal thread of the locking nut (20) is matched with the external thread on; one end, far away from the straight rod (17), of the movable head (18) is in a circular truncated cone shape, the upper bottom surface of the circular truncated cone is far away from the straight rod (17), and the diameter of the upper bottom surface is smaller than the minimum diameter of the first reducing through hole (11); the lower bottom surface of the circular truncated cone is close to the straight rod (17), the diameter of the lower bottom surface is larger than the minimum diameter of the first variable-diameter through hole (11), and the diameter of the lower bottom surface is smaller than the maximum diameter of the first variable-diameter through hole (11); the included angle between the generatrix of the circular truncated cone and the upper bottom surface is 100-110 degrees.

7. The dust-proof unloading device for the cylinder cover according to claim 6, characterized in that: the compression spring (6) is a spiral spring, the outer diameter of the compression spring (6) is smaller than the maximum diameter of the second reducing through hole (15) and larger than the minimum diameter of the second reducing through hole (15), and the outer diameter of the compression spring (6) is smaller than the maximum diameter of the circular truncated cone in the movable head (18).

8. The dust-proof unloading device for the cylinder head according to claim 7, characterized in that: the unloading valve comprises an unloading valve outer sleeve (3), an unloading valve inner sleeve (4), an unloading valve core (5) and a compression spring (6) which are coaxially arranged, wherein a first thread cylinder (10) in the unloading valve outer sleeve (3) is screwed in an unloading oil way (2), a second thread cylinder (14) in the unloading valve inner sleeve (4) is screwed in a first connecting seat (9), a movable head (18) in the unloading valve core (5) is positioned in the first thread cylinder (10), a threaded rod (16) in the unloading valve core (5) is positioned on one side, away from the second thread cylinder (14), of a second connecting seat (13), one end of the compression spring (6) abuts against the movable head (18), and the other end of the compression spring (6) abuts against the variable diameter position of a second variable diameter through hole (15).

9. The dust-proof unloading device for the cylinder head according to claim 8, characterized in that: the connecting device further comprises a gasket (21), wherein the gasket (21) is located between the first connecting seat (9) and the second connecting seat (13).

10. The dust-proof unloading device for the cylinder head according to claim 8, characterized in that: the distance between the inner surface of the second connecting seat (13) and the outer surface of the straight rod (17) is 0.3mm-0.6 mm.