119 results about "Double lip" patented technology

The invention discloses a lipstick with sun-screening and anti-free radical effects. The lipstick comprises natural beeswax, carnauba wax, coconut oil, jojoba oil, olive oil, shea butter, nanometer-sized titanium dioxide, a polymethylsilsesquioxane coated organic sun-screening agent ethylhexyl methoxycinnamate and additives. According to the invention, nanometer-sized titanium dioxide used as a physical sun-screening agent and the polymethylsilsesquioxane coated organic sun-screening agent are employed, effects of antioxidation and removal of free radicals of vitamin E are cooperatively used, so the lipstick provided by the invention causes no allergy or discomfort to a human body after usage. Long-term usage of the lipstick enables skin aging to be delayed and the skin of a lip to be improved and endows people with healthy, soft, moist and full double lips.

A double lip seal for a dust excluder seal for a cylindrical reciprocating tube connected to a recreational or utility vehicle, wheel and an off-road motorcycle or bicycle. The seal includes an oil side beam generally parallel to the axis of the reciprocating members and having a spring loaded dust excluder lip for engaging the inner cylindrical tube and wherein the spring is protected from dust and dirt by an outer excluder lip that prevents the garter sprung lip from fouling. In addition the lip is designed with a negative R-value which allows the sprung lip to rotate and position the geometry of the lip to act as a dust excluder lip. The protected spring can now compensate for lip wear which enhances the service life of the seal. The seal also includes an air side beam having a second sealing lip engaging the inner cylindrical tube.

The present invention relates to water-proof structure for an outdoor pan rotary shaft, and consists of a pan outer casing, and a rotary shaft and a pan base coaxially arranged inside the pan outer casing. Wherein, the bottom of the pan outer casing and the rotary shaft are coaxially provided with a ring type outer water-proof ring. The upper part of the pan and a pillow block of the pan base are coaxially provided with a ring type inner water-proof ring. A sealing frame is arranged between the pillow block of the pan base and the pan outer casing. A double lip sealing ring of integrated forming is arranged between the sealing frame and the pillow block of the pan base. The water-proof structure has no requirement of high assembling and processing accuracy for the rotary shaft and the outer casing due to the adoption of the double lip sealing ring and the radial roaming of the sealing frame with the strength of the pressure, and has the advantages of good water-proof property, reducing cost, improving sealing effect and reliability, simple whole structure, convenient assembling and maintenance.

Process for fastening an accessory to a hollow body obtained by molding a molten plastic parison and using a plastic connector comprising coupling means for the accessory and a stop surface intended to limit the penetration of the connector into the molten plastic, according to which the stop surface is provided with a curved double lip (or one-piece part having two concentric curved edges, i.e., two protuberances located preferably at its periphery, which are concentric and are in relief relative to the remainder of the part) and the connector is welded to the inner wall of the parison using this double lip.

The invention discloses a lifting rod-type ball valve, comprising a valve body, a valve seat, a ball body, a valve cover, a valve rod, a plurality of groups of sealing fillers, a packing gland and an execution mechanism. The sealing surface of the valve seat comprises a sealing area and a supporting area. The sealing area comprises an internal sealing surface and an external sealing surface. The internal sealing surface and the external sealing surface are separated by a buffer groove. The supporting area comprises an internal supporting surface and an external supporting surface. The internal supporting surface is disposed on the inner side of the internal sealing surface. The external supporting surface is disposed on the outer side of the external sealing surface. In this way, a double-lip sealing surface is formed. The upper outer surface and lower outer surface of the ball body behind a spherical surface sealing ring are respectively cut with elastic compensation grooves which are opposite to each other and perpendicular to the axis of the sealing ring. The wall surface of a gland cavity of the valve cover is provided with a manhole. A guide cavity has a fully enclosed structure. A packing chamber is also provided with a spacer ring located in the middle of several groups of sealing fillers. A position of the corresponding spacer ring on the sidewall of a packing cavity of the valve cover is provided with a sealing greasing hole communicated with the spacer ring and equipped with a sealing grease check valve in a radial direction.

The invention relates to a hydraulic damper with excellent tightness, which is provided with a cylinder body (4), a piston (8), a piston rod (2), a guiding sleeve(3), a front rubber cup(5), an elastic element (6), a middle rubber cup (7)or a fixing ring(7), a blanking element(12), a washer (10)and a rear rubber cup (11), wherein the periphery of the guiding sleeve(3) is provided with a clamping block (3.1), the cylinder body (4) is provided with a bayonet (4.1) matched with the clamping block (3.1), the periphery of the blanking element(12) is provided with a clamping block (12.1), and a bayonet (4.3) is arranged on the cylinder body (4), and the cylinder wall of the hydraulic damper cylinder body (4) is provided with a liquid releasing groove (4.2); the piston (8) is arranged to be a transverse I-shaped contoured structure, and comprises two piston rings(8.1 and 8.3) in the front and at the back and a piston column (8.2) in the middle; the piston column in the middle is sleeved with a floating ring (9), wherein the front piston ring wall is provided with a damping hole (8.4); and the front rubber cup (5), the middle rubber cup (7) and the rear rubber cup (11) of the hydraulic damper are arranged to be internal and external double-lip structures. The hydraulic damper has simple assembling and firm connection among the guiding sleeve and the blanking element with the cylinder wall of the cylinder body, the piston rod can position accurately, and the damping effect and the tightness are good.

The invention discloses a GLP03 type paddle valve comprising a floodgate frame and a flashboard; a seal valve buckle is fixed on the floodgate frame; the seal valve buckle is in a U-shaped structure which is arranged between the flashboard and an installation wall surface; the opening of the U-shaped structure is towards the flashboard; a double lip-shaped rubber sealing strip is installed in the sealing floodgate frame; and the lip-shaped part of the double lip-shaped rubber sealing strip is contacted with the flashboard, which plays a seal function. Interference close fit is formed between the lip-shaped part of the double lip-shaped rubber sealing strip and the flashboard, thus preventing fluid medium at the internal direction and the external direction of the paddle valve from passing through, and realizing bidirectional water stopping effect. Foamed rubber sealing strips are arranged between the floodgate frame and the installation wall surface and between the sealing valve frame and the installation surface, which play the function of water stop. The paddle valve of the invention has simple and lightweight design structure, high strength, convenient installation and maintenance and good bidirectional water stopping effect; compression resisting safety factor is larger than 6; and the highest adaptive water pressure can reach 10 water heads.

The invention provides a double vacuum sucker lifting appliance, solving the problems that in the process of carrying materials by the vacuum sucker lifting appliance, work time is delayed when vacuum leakage and maintenance delays occur. The vacuum sucker lifting appliance comprises a sucker body and a buffer support which is articulated with the sucker body, wherein, the buffer support comprises a guide pillar and buffer springs which are sheathed on the upper and lower sides of the guide pillar; the guide pillar between two buffer springs are sheathed on the hanger frame; the lower end surface of the sucker body is designed to be a bilabial structure by which a central chamber and a circular chamber formed by the sucker body are respectively opened with vent hole which are communicated with two vacuum pumps through pipelines. By improving the sucker structure and changing the connection type between the sucker and the vacuum pump, the invention effectively strengthens the adsorption capability of the double vacuum sucker lifting appliance, simultaneously ensures working reliability and effectively improves work efficiency.

Process for fastening an accessory to a hollow body obtained by molding a molten plastic parison and using a plastic connector comprising coupling means for the accessory and a stop surface intended to limit the penetration of the connector into the molten plastic, according to which the stop surface is provided with a curved double lip (or one-piece part having two concentric curved edges, i.e., two protuberances located preferably at its periphery, which are concentric and are in relief relative to the remainder of the part) and the connector is welded to the inner wall of the parison using this double lip.

The invention relates to the field of screw vacuum pumps, and provides a screw vacuum pump with a built-in nitrogen seal at the exhaust side. In a nitrogen gas flow sealing chamber arranged between amechanical seal of a front shell and a double-lip sealing ring, nitrogen gas flow can always uphold a constant micro-positive pressure state, so that oil vapor in a gear box can be prevented from entering a pump chamber of the screw vacuum pump, corrosive media in the pump chamber of the screw vacuum pump can be prevented from entering the gear box to pollute lubricating oil, the mechanical seal and the double-lip sealing ring can be effectively protected from being damaged, and the service life of a sealing member can be prolonged.

The invention relates to a bearing box or gear box lubricating oil (grease) sealing device for a rotating shaft of mechanical equipment, in particular to an outside mounted type two-lip framework oil seal. The outside mounted type two-lip framework oil seal comprises a sealing lip, a crown part, a spring groove, a limiting step, a shoulder part, a back part, a waist part, a secondary lip and a locating groove, wherein an integral structure of the outside mounted type two-lip framework oil seal is formed by the sealing lip, the crown part, the spring groove, the limiting step, the shoulder part, the back part, the waist part, the secondary lip and the locating groove; the sealing lip is arranged on the outer side of the crown part; the spring groove is formed in the inner side of the crown part; the secondary lip is arranged on the outer side of the waist part; the outside mounted type two-lip framework oil seal further comprises a circular pad type framework and an L-shaped framework; the limiting step is integrally connected with the shoulder part, the back part, the secondary lip, the waist part, the crown part, the sealing lip, the spring groove, the circular pad type framework and the L-shaped framework; a spring is arranged in the spring groove. The secondary lip is used for preventing external impurities such as water vapor and smoke from entering a sealing cavity; the sealing lip is used for preventing oil (grease) in the sealing cavity from leaking outside. The oil seal thoroughly solves the problem of inconvenient online dismounting, has the advantages of simple structure, low cost, high adaptability and convenience in online replacement, and can totally replace a standard framework oil seal.

The invention discloses a water pump shaft connecting bearing with a sealing structure and belongs to the field of machinery. The water pump shaft connecting bearing comprises an outer ring, a shaft, a rolling body, a retaining frame, a double-lip seal ring and a sealing structure and the like. The rolling body is installed in a rolling path between the outer ring and the shaft through the retaining frame, the outer diameter of the double-lip seal ring is embedded in a dustproof sealing groove, double lips on the inner diameter are in interference fit with the shaft, the sealing structure is installed at the end of an impeller of the water pump shaft connecting bearing and located on the outer side of an outer rolling path, and the sealing structure is a clamping ring type seal ring or a compound sealing structure with a water throwing ring. Direct contact between dirt in the working environment and an inner lip of the seal ring is effectively avoided, the seal ring protection effect is achieved, and the abrasion speed of a lip on the inner side of the seal ring is reduced.

The invention relates to a hydraulic rotary joint comprising a rotary body (1) and a rotary shaft (2). The hydraulic rotary joint is characterized in that the bottom end of the rotary shaft (2) is axially inserted from the top end of the rotary body (1), the top end of the rotary shaft (2) extends out of the rotary body (1), a flange (3) is arranged between the top end of the rotary body (1) and the rotary shaft (2), a rotary sealing ring (5) and a dustproof sealing ring (6) are arranged in a circular groove between the rotary body (1) and the rotary shaft (2), an upper lip and a lower lip (6.1) are arranged on one side of the dustproof sealing ring (6) contacting with the rotary shaft (2) to form double lips, and the upper lip and the lower lip (6.1) are attached to the outer wall of the rotary shaft (2). According to the hydraulic rotary joint, dust is not prone to entering and oil is not prone to leakage. Besides, a rotary angle is large, interference does not exist among pipelines, and operation and maintenance are very convenient.

The invention discloses a novel hub motor oil seal of an electric vehicle. The novel hub motor oil seal comprises a rubber double lip, a metal framework and a tightening spring, wherein the metal framework is tightly bonded with the rubber double lip through sulfuration, and the tightening spring is installed in a spring groove of the rubber double lip. Lubricating grease is added between the rubber double lip. A dust-proof lip at the outermost end of the rubber double lip is in an exocentric structure. The novel hub motor oil seal of the electric vehicle has the advantages that the structure is simple, producing costs are low, and functions of high protecting capacity against foreign matters, low working temperature and energy consumption of bearings and small friction torque of a seal lip can be achieved.

The invention relates to an outdoor tripod head with a good waterproof function and a dustproof function and the outdoor tripod head consists of an outer shell of the tripod head, a rotation axis and a deck mechanism. The rotation axis is coaxially arranged in the outer shell of the tripod head and a base is fixedly arranged at the end of the rotation axis extending out of the outer shell of the tripod head. The deck mechanism is fixedly connected with the outer shell of the tripod head and drives the outer shell of the tripod head to rotate around the rotation axis. The invention has an innovation point that: the part of the rotation axis extending out of the outer shell of the tripod head is coaxially sheathed with a bottom support plate which is arranged on the bottom surface of the outer shell of the tripod head, and the inner plane of the bottom support plate is provided with a cylinder sleeve the inside of which is embedded with a sealing ring which is coaxially sheathed on the rotation axis. The outdoor tripod head is simple in structure and scientific and rational in design, utilizes a double-lip sealing ring and improves the sealing effect and the reliability of the rotation axis of the outdoor tripod head. By virtue of the bottom support plate, the coaxial degree of the rotation axis and the installing hole of the outer shell of the tripod head is automatically adjusted, the installation and maintenance are more convenient and the processing cost is lower, so the outdoor tripod head is an innovative outdoor tripod head which improves the waterproof function and dustproof function of the rotation axis.

The invention relates to a hydraulic center rotary joint characterized in that the lower end of a rotary shaft (2) is axially inserted into a rotary body (1) from the upper end of the rotary body (1), seven main oil-way holes and a center oil drainage hole are axially formed in the rotary shaft (2), seven main oil ports are radially formed in the rotary body (1) to be correspondingly communicated with the seven main oil-way holes in the rotary shaft (2), a dustproof ring (12) is arranged in a circular groove between the rotary body (1) and the rotary shaft (2), an upper lip and a lower lip (12.1) are arranged on one side of the dustproof ring (12) contacting with the rotary shaft (2) to form double lips, and the upper lip and the lower lip (12.1) are attached to the outer wall of the rotary shaft (2). According to the hydraulic center rotary joint, dust is not prone to entering, oil is not prone to leakage, fixed parts of a hydraulic system and a circuit can rotate 360 degrees relative to rotary parts. Besides, the upper portions and the lower portions of oil-ways are communicated, and the oil-ways and the circuit are not connected in serial.

A radial shaft seal for sealing a rotating shaft led out from a space filled with a fluid medium, for example for sealing the drive shaft of a coolant pump, minimizes wear, especially the starting wear acting upon the sealing lips in double lip sealing systems, and allows end-of-line motor tests with coolant pumps without cooling liquid for up to several hours without damages to the radial shaft seal. The radial shaft seal includes two sealing bodies, an outer lip element on the pressure side and an inner lip element on the atmosphere side, each having a sealing cylinder resting on the shaft or the sleeve, arranged in a sealing housing with a joined metal supporting body, the sealing cylinders having three adjoining sealing cylinder regions such that on each pressure side a conical inlet surface and opposite thereof on each negative pressure side a conical outlet surface are provided, in each case a cylindrical contact zone being present between the conical inlet surface and the conical outlet surface. A lubrication chamber is defined by the outer lip, the supporting body, the inner lip element having the inner lip and the shaft, or the sleeve and is sealed on all sides, a lubricant medium which is flowable at room temperature and which has a kinematic viscosity in the range of 5,000 mm2 / s to 1.000 mm2 / s at a residual excess pressure of 0.005 bar to 0.01 bar being arranged in the lubrication chamber.

The invention relates to a double-lip distortion resistance air inlet duct structure suitable for the crosswind working condition. The structure comprises a first-stage lip and a second-stage lip, a flange is designed on the first-stage lip and is responsible for being connected with a duct casing, a lemniscate is adopted for the lip curve, and thus air flows can enter a duct fan at a smallest loss under the crosswind-free working condition. According to the double-lip distortion resistance air inlet duct structure suitable for the crosswind working condition, the air inlet quality of the crosswind-free working condition cannot be lowered firstly, and the excessive extra weight cannot be caused. On the other hand, when a traditional air inlet duct encounters crosswind, flow separation extremely easily occurs on the windward sides of the lips, and thus flow field distortion is caused; and according to the double-lip distortion resistance air inlet duct structure suitable for the crosswind working condition, the separation phenomenon is obviously inhibited, air flow flowing is stable, and the airflow distortion strength is obviously lowered.

The present invention relates to a water pump bearing, and belongs to the technical field of bearing equipment. The water pump bearing comprises an outer ring, a core shaft, a double lip sealing ring, a ball retainer, column retainers, rolling columns and a steel ball, wherein the rolling column is arranged in the window hole of the column retainer, the steel ball is arranged in the pocket hole of the ball retainer, groove channels and rolling channels are processed on the outer ring and the core shaft, the steel ball rolls in the groove channel, the rolling column rolls in the rolling channel, the outer diameter of the double lip sealing ring is arranged in the sealing ring threaded groove of the outer ring, the inner diameter of the double lip sealing ring is connected with the core shaft, and the double lip sealing ring is made from a nitrile butadiene rubber. According to the water pump bearing of the present invention, the ball retainer, the column retainer and the double lip sealing ring are additionally arranged on the base of the existing bearing, such that the falling out of the rolling body during the installation and the disassembly is prevented, it is ensured that the bearing does not produce the oil leakage condition, and the invasion of external impurities is prevented; and the specified column end radial dynamic load of the present invention is increased by 25 KN compared with the specified column end radial dynamic load of the previously-designed structure, such that advantages of high bearing capacity, long service life, good rigidity, high rotation degree and the like are provided, and the failure rate is almost zero after the water pump bearing is used by customers.

The invention belongs to the technical field of sealing and discloses a dynamic pressure balance rotary sealing part. The pressure borne by a second sealing lip is reduced based on a spiral sealing principle and through the pumping function on fluid arranged in sealing gaps in a filling mode in the rotating process, and reliable sealing under the high-pressure and high-speed sealing working condition is achieved through coordination of multiple sealing. The dynamic pressure balance rotary sealing part is of a double-lip sealing structure and is composed of a rigid sealing ring (1) and an oil seal (2). The dynamic pressure balance rotary sealing part is characterized in that the sealing face of the rigid sealing ring (1) is provided with a backflow groove (3), a sealing gap is not larger than 1 mm, and the rigid sealing ring is located on the oil side. The sealing part is high in designability, good in sealing reliability, long in service life, suitable for high-pressure rotary sealing occasions, particularly suitable for high-speed and high-pressure rotary sealing of shafts / cylinders and suitable for reliable sealing of 0.05 MPa-2 MPa and 10 m / s-40 m / s rigorous working conditions.

The invention relates to an elastically-sealed automatic sprinkler head. The automatic sprinkler head comprises a body, a thermosensitive element, an adjusting bolt, a water splashing deflector, a ball seat, an elastic gasket, a cover-shaped elastic sheet, an inner sealing washer, an outer sealing washer, a sealing washer, a sealing ring and the like, wherein the elastic gasket, the ball seat and the cover-shaped elastic sheet can be selectively and respectively inosculated and equipped with the inner sealing washer, the outer sealing washer, the integrated sealing washer and the sealing ring with different section shapes such as a single-lip shape, a double-lip shape, an outward-turned single-lip shape, an outward-turned double-lip shape and an L shape. By virtue of different sealing surface types, the non-extrusion type elastic sealing as well as hydraulic-power sealing and hydraulic-pressure sealing of the automatic sprinkler head can be realized, the required sealing surfaces are reduced, the assembly pretightening force of the sealing surfaces and the normal temperature creep value of non-metal materials are reduced, long-time sealing performance can be achieved, and besides, when the thermosensitive element is opened and released in a fire, sealing elements are not adhered to the sealing surfaces of the body and can be separated easily, so that the sprinkler head can automatically spraying water for extinguishment.

Disclosed is a slurry pump bracket end bearing oil seat structural combination. The slurry pump bracket end bearing oil seat structural combination comprises a bracket body 1, a bearing 3, a bear end cover 4, an oil seal 5', a shaft sleeve 6 which sleeves a pump spindle and rotates along with the pump spindle, a cooling water channel 8, a vertical oil drainage channel 9 and a machine a sump 10. The slurry pump bracket end bearing oil seat structural combination is characterized in that the oil seal 5' is mounted inside the flange of the bearing end cover 4 and fixed firmly; the flange of the bearing end cover 4 and the bracket body 1 are compressed through a sealing gasket and can avoid oil leakage; the cooling water channel 8 is arranged around the bearing 3 and used for reducing the working temperature of lubricant and the oil seal 5'; the vertical oil drainage channel 9 comprises a first channel perpendicular to the pump spindle, and a second channel parallel to the pump spindle, wherein the first channel and the second channel are communicated with each other and rapidly drain returned machine oil passing through the bearing to the bottom of the sump 10; the oil seal 5' is of a fluororubber double-lip structure with a metal framework.

The invention discloses a Y-shaped high-elasticity two-lip sealing ring and a sealing structure. The Y-shaped high-elasticity two-lip sealing ring comprises a sealing ring main body, one side of the sealing ring main body is extended outwards to be provided with an upper sealing lip and a lower sealing lip, the upper sealing lip, the lower sealing lip and the sealing ring main body are arranged ina Y shape, and a V-shaped sealing lip gap is formed between the upper sealing lip and the lower sealing lip. The sealing structure based on the Y-shaped high-elasticity two-lip sealing ring comprisesthe two-lip sealing ring and further comprises an upper sealing part and a lower sealing part, the lower sealing part is provided with a sealing groove, and the two-lip sealing ring is arranged in the sealing groove. The Y-shaped high-elasticity two-lip sealing ring and the sealing structure have the advantages of convenient construction, long service life, good sealing performance, flexible andconvenient application and the like which the prior art does not have.

The present disclosure relates to a double-lip seal of a pneumatic spring brake chamber for a vehicle, the double-lip seal has sealing performance between an inner circumferential surface of a through-hole of an adaptor housing and an outer circumferential surface of an actuator rod to prevent degradation in sealing performance of the lip seal, thereby maintaining constant sealing performance and preventing fluid leakage.

The invention relates to a double-lip oil seal device capable of regulating pressure automatically. The double-lip oil seal device capable of regulating the pressure automatically comprises a double-lip oil seal, a guide sleeve, a circular base plate, a buffer spring, a guide screw and a circular top cover, wherein the outer lip of the double-lip oil seal is slidably adhered to the outer wall of the guide sleeve in a sealed way; the inner lip of the double-lip oil seal is slidably adhered to a system working shaft in a sealed way; the circular base plate is arranged on the double-lip oil seal; a screw hole matched with the guide screw is formed on the circular base plate; the guide screw is arranged between the double-lip oil seal and the circular top cover; the guide screw is in threaded fit with the screw hole on the circular pad plate; the buffer spring is sleeved on the guide screw and is positioned between the circular base plate and the circular top cover; and the circular top cover is fixed on an outer end port of the guide sleeve through a fixing bolt. The double-lip oil seal device capable of regulating the pressure automatically can regulate the pressure automatically according to the pressure condition in a machine and ensure a stable pressure state in the machine, so that an explosion hazard caused by overhigh pressure is effectively prevented, the service life of inner components is prolonged, and excellent performance of the machine is ensured.

The invention discloses a double-lip oil-seal sealing device. The double-lip oil-seal sealing device is provided with a framework, wherein the framework is provided with lip rubber, reinforcing ribs, springs, lateral lips and first annular grooves; the lip rubber and the first annular grooves are arranged on a plane of a sealing surface of the framework; the lateral lips are arranged at the bottoms of the first annular grooves; springs are arranged on gaps opposite to the sealing surface of the framework. The double-lip oil-seal sealing device provided by the invention has the advantage that a plane where shafts are vertical to each other is sealed in combination with characteristics of a radial oil seal and an axial oil seal, and has a relatively good dustproof effect.

A thrust bearing with a improved sealing assembly includes external envelop such as with close rim at both ends having flat face to provide room for rubber lip folding and sealing such as double lip seal with two axial lips. The axis of rubber lips are inclined with relevant mating part. The extreme ends of the envelop envelops the delicate lip of rubber seals. The portion of the envelop ID [20] is put in a manner to guides roller cage assembly and create sealing at [08, 09]. The bearing external envelop is used as stiffener for body of double lip seal. The shape and design of the external machine cover face accommodate lips of seals, protect seals lips and hold the bearing together.

The invention discloses a double-lip sealing ring for a rotary shaft of an air conditioner compressor. The double-lip sealing ring consists of a first sealing seat ring, a limit taper sleeve, a second sealing ring, a bearing tray and a bearing gasket; the limit taper sleeve, the second sealing ring, the bearing tray and the bearing gasket are arranged in the cavity of the first sealing seat ring in turn; and the sectional shape of a bearing lug boss ring is right-angled trapezoid, the right-angled waist is inside, and the oblique waist is outside. The sectional shape of the bearing lug boss ring is changed into the right-angled trapezoid from rectangle; and after the bearing lug boss ring is pressed, the radial component force of the pressure acted on the bearing lug boss ring is outward and has minimum influence on the limit taper sleeve, thus ensuring the shapes of sealing lips and the stability of tension, ensuring the sealing performance, eliminating the single offset phenomenon produced after a sealing lip belt is pressed and deformed, reducing the friction force between the sealing lip belt and the rotary shaft, prolonging the service life of the whole product and reducing the energy consumption.