CN108451694B

CN108451694B - Improved cervical tractor

Info

Publication number: CN108451694B
Application number: CN201711458716.6A
Authority: CN
Inventors: 唐朝贤; 何云; 周晓红; 王亚晖; 龚靖淋
Original assignee: Chongqing Tumour Institute
Current assignee: Chongqing Tumour Institute
Priority date: 2017-12-28
Filing date: 2017-12-28
Publication date: 2020-06-16
Anticipated expiration: 2037-12-28
Also published as: CN108451694A

Abstract

The invention discloses an improved neck tractor, which comprises a tractor body; the tractor body comprises a front neck support frame and a rear traction neck support, and the front neck support frame is connected with the rear traction neck support through a hanging buckle; the end surface of the back traction neck support, which is contacted with the neck of the human body, is provided with a plurality of longitudinal air columns, and two adjacent longitudinal air columns are connected through at least one transverse air column; the longitudinal air column near one end of the rear traction neck support is connected with an exhaust pipe, and the exhaust pipe is provided with an exhaust valve; the longitudinal air column near the other end of the rear traction neck support is connected with an air inlet pipeline, the air inlet end of the air inlet pipeline is connected with a heating temperature control device, and an air throttle is arranged on the air inlet pipeline; the air inlet end of the heating temperature control device is connected with the air charging bag through an air pipe, and an air inlet valve is arranged on the air pipe. The neck support device realizes good support for the neck of a human body, avoids the phenomenon of spasm or convulsion generated when the back traction neck support is initially contacted with the human body, ensures that the temperature of the inner side surface of the traction neck support is proper to the temperature of the human body, and improves the experience feeling of users.

Description

Improved cervical tractor

Technical Field

The invention relates to the technical field of medical auxiliary equipment, in particular to an improved neck retractor.

Background

The neck tractor can be used for preventing and treating various cervical spondylosis and compression symptoms caused by the cervical spondylosis, can increase the supply of cerebral blood and oxygen, is beneficial to restoring physical strength and energy, and can also be used for preventing various senile cervical spondylosis. The neck tractor reduces repeated friction and bad stimulation to the pressed marrow and nerve roots by limiting the movement of the cervical vertebra, is beneficial to eliminating edema and inflammation of tissues such as spinal cord, nerve roots, joint capsules, muscles and the like, can increase intervertebral space and intervertebral foramen, and relieves or even relieves the stimulation and the compression on the nerve roots. However, the inner side surface of the rear traction neck support of the existing neck tractor cannot be in good contact with the neck of a human body, thereby affecting the treatment effect of the neck tractor on the neck of the human body; in addition, the inner side surface of the back traction neck brace is cool, and when the back traction neck brace is initially contacted with the neck of a human body, a person is easy to generate instant spasm or convulsion, so that the neck of the human body is worsened; meanwhile, after the inner side surface of the back traction neck brace is contacted with a human body for a long time, the temperature of the inner side surface of the back traction neck brace is suitable for the temperature of the human body, and the use experience of a user is reduced.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide an improved neck tractor, which realizes good support for the neck of a human body, avoids the phenomenon of spasm or convulsion generated when a back traction neck support is in initial contact with the human body, ensures that the temperature of the inner side surface of the traction neck support is proper to the temperature of the human body, and improves the experience feeling of users.

The invention provides an improved cervical tractor, which comprises a tractor body; the tractor body comprises a front neck support frame and a rear traction neck support, and the front neck support frame is connected with the rear traction neck support through a hanging buckle; the end face of the rear traction neck brace, which is contacted with the neck of a human body, is provided with a plurality of longitudinal air columns, and two adjacent longitudinal air columns are connected through at least one transverse air column; the longitudinal air column near one end of the rear traction neck support is connected with an exhaust pipe, and the exhaust pipe is provided with an exhaust valve; the longitudinal air column near the other end of the rear traction neck support is connected with an air inlet pipeline, the air inlet end of the air inlet pipeline is connected with a heating temperature control device, and an air throttle is arranged on the air inlet pipeline; the air inlet end of the heating temperature control device is connected with the air charging bag through an air pipe, and an air inlet valve is arranged on the air pipe.

Preferably, the foreneck support frame comprises a foreneck support, a mandible support, two support rods and two telescopic rods, the two support rods are symmetrically arranged at the shoulder positions at the left end and the right end of the foreneck support, and the two ends of the mandible support are respectively hinged with the upper ends of the two support rods; the lower ends of the two telescopic rods are hinged with the chest position of the front neck support, the two telescopic rods are arranged in bilateral symmetry, and the upper ends of the two telescopic rods are hinged with the front part of the lower jaw bone support.

Preferably, the telescopic rod comprises a screw rod, a sleeve and a support rod, the lower end of the support rod is hinged to the front neck support, the upper end of the support rod is rotatably connected with the lower end of the sleeve, a threaded hole with an opening in the upper end is longitudinally formed in the sleeve, the lower end of the screw rod is in threaded connection with the threaded hole of the sleeve, and the upper end of the screw rod is hinged to the lower jaw support.

Preferably, the lower end of the sleeve is provided with a counter bore groove, a bearing is fixedly arranged in the counter bore groove, and the upper end of the support rod is embedded in an inner ring of the bearing; the counter bore groove of the sleeve is provided with an annular step sealing cover, the annular step sealing cover penetrates through the supporting rod to be connected with the lower end of the sleeve, and an annular step of the annular step sealing cover is in close contact with the bearing.

The invention has the beneficial effects that:

the invention can send the external gas into the heating temperature control device through the air bag, the heating temperature control device heats the sent gas to the designated temperature and then sends the heated gas into the longitudinal gas column and the transverse gas column through the gas inlet pipeline, so that the temperature of the gas in the longitudinal gas column and the transverse gas column is proper to the temperature required by the neck of the human body, and the blood circulation of the neck of the human body can be promoted; the design of the longitudinal air columns 121 and the transverse air columns 122 is convenient for realizing support and soft contact on the neck of a human body; the design of the exhaust pipe and the exhaust valve is convenient for people to adjust the air pressure of the longitudinal air column and the transverse air column or exhaust air according to needs; in conclusion, the neck of the human body is well supported, the phenomenon that the back traction neck brace is in initial contact with the human body to generate spasm or twitch is avoided, the condition that the temperature of the inner side surface of the traction neck brace is appropriate to the temperature of the human body is ensured, and the user experience is improved.

Drawings

FIG. 1 is a schematic structural view of example 1;

FIG. 2 is a schematic view showing the structure of a carotid artery compressor in accordance with example 1;

fig. 3 is a schematic structural view of a back traction neck brace in embodiment 1;

fig. 4 is a schematic structural view of the telescopic rod in embodiment 1;

FIG. 5 is a schematic view showing the structure of a carotid artery compressor in example 2;

fig. 6 is a cross-sectional view a-a of fig. 5.

Reference numerals: 1-retractor body, 11-anterior cervical bracing frame, 111-anterior cervical bracing, 112-mandibular brace, 113-bracing bar, 114-telescopic bar, 1141-screw, 1142-sleeve, 1143-bracing bar, 1144-bearing, 1145-annular step cover, 12-posterior traction cervical bracing, 121-longitudinal air column, 122-transverse air column, 123-exhaust pipe, 124-exhaust valve, 125-air inlet pipe, 126-heating temperature control device, 127-air throttle, 128-air-inflating bag, 129-air inlet valve, 2-carotid compressor, 21-bracing body, 211-annular cavity, 212-installation cavity, 213-annular wall, 214-chute, 22-annular compression seat, 221-supporting block, 222-counter bore, 223-angle hole, 224-rear convex annular sphere, 23-compression rod, 231-compression ball, 24-adjusting nut, 25-compression spring, 26-annular compression block, 261-front convex annular sphere, 27-non-slip pad, 28-annular cushion block, 31-shell, 311-bearing beam, 312-bearing, 32-rotary annular column, 33-inner support column, 331-inlet swing angle hole, 332-annular sphere, 333-outlet swing angle hole, 34-stabilizing device, 341-screw, 342-nut, 343-wedge-shaped sliding block, and 344-tension spring.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

Example 1

As shown in fig. 1 to 4, the present invention discloses a cervical traction apparatus for facilitating compression of carotid artery, comprising a retractor body 1 and a carotid artery compressor 2; the carotid artery compressor 2 is arranged on the left side or the right side of the retractor body 1; the retractor body 1 comprises a front neck support frame 11 and a back traction neck support 12, wherein the front neck support frame 11 is connected with the back traction neck support 12 through a hanging buckle. Through using carotid compressor 2 on tractor body 1 for when tractor body 1 is realizing pulling the treatment or alleviating to human neck, also can adopt carotid compressor 2 to control human carotid's blood supply volume simultaneously, compromise the control to the traction of neck and to carotid blood supply volume, provide good treatment and alleviate for this type of special patient's the state of an illness, improved the practicality.

Specifically, the carotid artery compressor 2 comprises a shell 31, a rotary annular column 32, an inner support column 33 and a compression rod 23, wherein two symmetrically arranged bearing beams 311 are fixedly installed in the shell 31, the inner side surfaces of the two bearing beams 311 are fixedly connected with bearings 312, the inner rings of the bearings 312 are connected with the rotary annular column 32, and the inner wall of the rotary annular column 32 is in threaded connection with the outer contour of the inner support column 33; the pressing bar 23 is rotatably installed in the inner support column 33 at a plurality of angles. The rotating annular column 32 is screwed, and the inner support column 33 can move along the axial direction due to the threaded connection of the rotating annular column 32 and the inner support column 33, so that the compression rod 23 is driven to move, the compression feeling when the compression rod 23 is contacted with the human carotid artery is controlled conveniently, the compression feeling of the end head of the compression rod 23 and the human carotid artery is controlled finely by combining the angle adjustment of the compression rod 23, and the good control of the blood supply of the human carotid artery is realized. Wherein, the middle part of the pressing rod 23 is spherical, and both ends of the pressing rod 23 are provided with pressing balls 231; an inlet swing angle hole 331, an annular spherical surface 332 and an outlet swing angle hole 333 which are mutually communicated are arranged in the inner support column 33, the pressing rod 23 sequentially penetrates through the inlet swing angle hole 331, the annular spherical surface 332 and the outlet swing angle hole 332, and the middle spherical area of the pressing rod 23 is embedded in the annular spherical surface 332 of the inner support column 33 in a matched mode. The cooperation of the central spherical region of the pressing rod 23 and the annular spherical surface 332 of the supporting column 33 facilitates the angular adjustment of the pressing rod 23 in the inner supporting column 33.

In addition, the carotid artery compressor 2 further comprises two stabilizing devices 34 symmetrically installed in the housing, each stabilizing device 34 comprises a screw 341, a nut 342, a wedge-shaped sliding block 343 and a tension spring 344, one end of the screw 341 is fixedly connected with the housing 31, the other end of the screw 341 is connected with the nut 342, the wedge-shaped sliding block 343 is slidably sleeved on the screw 341 between the nut 342 and the inner wall of the housing 31, one end of the tension spring 344 is connected with the wedge-shaped sliding block 343, the other end of the tension spring 344 is connected with the inner wall of the housing 31, and the tension spring 344 is sleeved on the screw 341;

the inner wall of the outlet swing angle hole 333 is in an inverted cone shape, and the wedge-shaped surface of the wedge-shaped sliding block 343 is tightly attached to the inner wall of the outlet swing angle hole 333. An operator screws and rotates the annular column 32 as required, the inner support column 33 moves in the axial direction, and the wedge surfaces of the two wedge sliding blocks 343 are kept in close fit with the inverted cone inner wall of the outlet swing angle hole 333 under the action of the respective tension springs 344 of the two wedge sliding blocks 343, so that the stability of the compression rod 23 during operation is improved; in addition, the nut 342 is matched with the screw 341, so that the limit position of the wedge-shaped sliding block 343 can be set, the limit position of the inner supporting column 33 moving in the axial direction can be set, and the practicability is improved.

Specifically, the front neck support frame 11 comprises a front neck support 111, a mandible support 112, two support rods 113 and two telescopic rods 114, wherein the two support rods 113 are symmetrically arranged at the shoulder positions at the left end and the right end of the front neck support 111, and the two ends of the mandible support 112 are respectively hinged with the upper ends of the two support rods 113; the lower ends of the two telescopic rods 114 are hinged with the chest of the front neck support 111, the two telescopic rods 114 are arranged in a left-right symmetrical mode, and the upper ends of the two telescopic rods 114 are hinged with the front part of the mandible support 112. The height of the front end of the front neck support 111 can be adjusted through the telescopic rod 114, so that the front neck support 111 can be in good contact with the neck of a human body, and the support of the front neck support 111 on the lower jaw of the human body is guaranteed. Wherein, telescopic link 114 includes screw rod 1141, sleeve 1142 and bracing piece 1143, and the lower extreme and the front neck brace 111 of bracing piece 1143 are articulated, and the upper end of bracing piece 1143 is rotatable to be connected with the lower extreme of sleeve 1142, is equipped with the open screw hole in upper end on the sleeve 1142 vertically, and the lower extreme and the screw hole threaded connection of sleeve 1142 of screw rod 1143, and the upper end and the mandibular bone brace 112 of screw rod 1141 are articulated. The extension and contraction of the screw 1141 can be realized by screwing the sleeve 1142, so that the height of the front end of the mandibular bone support 112 is adjusted to make the mandibular bone support 112 in good contact with the mandible of a human body. The lower end of the sleeve 1142 is provided with a counter bore groove, a bearing 1144 is fixedly arranged in the counter bore groove, and the upper end of the support rod 1143 is embedded in the inner ring of the bearing 1144; the counterbore of the sleeve 1142 is fitted with an annular step cover 1145, the annular step cover 1145 is connected to the lower end of the sleeve 1142 through the support rod 1143, and the annular step of the annular step cover 1145 is in close contact with the bearing 1144. The supporting rod 1143 is connected with the sleeve 1142 in a nested manner through a bearing 1144, so that the supporting rod 1143 and the sleeve 1142 rotate relatively; meanwhile, the design of the annular stepped sealing cover 1145 avoids the phenomenon that the bearing 1144 falls off.

In addition, the end surface of the back traction neck support 12 contacting with the neck of the human body is provided with a plurality of longitudinal air columns 121, and two adjacent longitudinal air columns 121 are connected through at least one transverse air column 122; an exhaust pipe 123 is connected to the longitudinal air column near one end of the rear traction neck support 12, and an exhaust valve 124 is arranged on the exhaust pipe 123; an air inlet pipeline 125 is connected to a longitudinal air column at the other end of the rear traction neck support 12, a heating temperature control device 126 is connected to the air inlet end of the air inlet pipeline 125, and an air throttle valve 127 is arranged on the air inlet pipeline 125; the air inlet end of the heating temperature control device 126 is connected with an air charging bag 128 through an air pipe, and an air inlet valve 129 is arranged on the air pipe. The external gas can be sent into the heating temperature control device 126 through the air bag 128, the heating temperature control device 126 heats the sent gas to a specified temperature and then sends the heated gas into the longitudinal gas column 121 and the transverse gas column 122 through the gas inlet pipeline 125, so that the temperature of the gas in the longitudinal gas column 121 and the transverse gas column 122 is proper to the temperature required by the neck of the human body, and the blood circulation of the neck of the human body can be promoted; and the design of the longitudinal air columns 121 and the transverse air columns 122 is convenient for realizing the support and the soft contact on the neck of the human body. The design of the exhaust pipe 123 and the exhaust valve 124 facilitates the adjustment of the air pressure or exhaust of the longitudinal air column 121 and the transverse air column 122 as required.

Example 2

As shown in fig. 5 and 6, the present embodiment includes substantially the same components and connection relations as those of embodiment 1, except that the carotid artery compressor 2 includes a support body 21, an annular compression seat 22, a compression rod 23 and an adjusting nut 24, the support body 21 is installed on the left side or the right side of the front neck support frame 11, the support body 21 is provided with an annular cavity 211 with an open outer side surface, the support body 21 is provided with a through installation cavity 212, and the installation cavity 212 and the annular cavity 211 have the same axial center line. An annular wall 213 formed between the installation cavity 212 and the annular cavity 211 is provided with two sliding grooves 214 which are symmetrically arranged, the annular pressing seat 22 is fittingly embedded in the installation cavity 212, two supporting blocks 221 which are symmetrically arranged are axially arranged on the annular pressing seat 22, and the two supporting blocks 221 of the annular pressing seat 22 are slidably embedded in the two sliding grooves 214 of the annular wall 213; two compression springs 25 are arranged in the annular concave cavity 211, one ends of the two compression springs 25 are connected with the bottom of the annular concave cavity 211, and the other ends of the two compression springs 25 are respectively connected with the two support blocks 221 of the annular pressing seat 22. The adjusting nut 24 is matched with the annular concave cavity 211, the adjusting nut 24 is connected with the outer ring wall or the inner ring wall of the annular concave cavity 211 through threads, and the end, close to the compression spring, of the adjusting nut 24 is tightly contacted with the two supporting blocks 221 of the annular pressing seat 22; the pressing rod 23 is rotatably installed in the annular pressing seat 22 at a plurality of angles. By arranging the two branch blocks 221 of the annular pressing seat 22 between the adjusting nut 24 and the compression spring 25, the annular pressing seat 22 can be close to or far away from the carotid artery of the human body by screwing the adjusting nut 24, so that the positions of the annular pressing seat 22 and the pressing rod 23 to the human body can be adjusted according to requirements, and the practicability is improved; the compressing rod 23 can be rotatably arranged in the annular compressing seat 22 at multiple angles, and the compressing feeling of the end of the compressing rod 23 and the human carotid artery can be finely controlled by adjusting the angle of the compressing rod 23, so that the blood supply of the human carotid artery can be well controlled.

Wherein, the middle part of the pressing rod 23 is spherical, and both ends of the pressing rod 23 are provided with pressing balls 231; the annular compression seat 22 is provided with a counter bore 222 and a swing angle hole 223 which are communicated with each other, and the transition area of the counter bore 222 and the swing angle hole 223 is provided with a rear convex annular spherical surface 224 which is matched with the middle spherical area of the compression rod 23; the counter bore 222 of the annular pressing seat 22 is provided with an annular pressing block 26, and the side of the annular pressing block 26 close to the swing angle hole is provided with a front convex annular spherical surface 261 matched with the middle spherical area of the pressing rod 23; the annular pressing block 26 is sleeved on the middle spherical region of the pressing rod 23, the annular pressing block 26 is embedded in the counterbore 222 and connected with the annular pressing seat 22, the middle spherical region of the pressing rod 23 is embedded in a space formed by the rear convex annular spherical surface 224 and the front convex annular spherical surface 261 in a multi-angle rotating manner, and the middle spherical region of the pressing rod 23 is in close contact with the rear convex annular spherical surface 224 and the front convex annular spherical surface 261. The middle spherical area of the compression rod 23 is rotatably embedded in a space enclosed by the rear convex annular spherical surface 224 and the front convex annular spherical surface 261 in multiple angles, and the middle spherical area of the compression rod 23 is tightly contacted with the rear convex annular spherical surface 224 and the front convex annular spherical surface 261, so that the middle spherical area of the compression rod 23 can rotate between the rear convex annular spherical surface 224 and the front convex annular spherical surface 261 and keep relative tight fit, and further the compression rod 23 can be fixed when rotating to a certain angle, thereby ensuring continuous compression on the carotid; and the whole structure of the design is simple, and the disassembly, the assembly and the maintenance are convenient.

Non-slip pads 27 are arranged between the rear convex annular spherical surface 224 and the front convex annular spherical surface 261 and the outer surface of the middle spherical area of the compression bar 23. The design of the anti-slip pad 27 further avoids the phenomenon that the compression rod 23 deflects and loosens in the using process, thereby ensuring that the compression rod 23 continuously controls the blood supply of the carotid artery. In addition, an annular cushion block 28 is arranged between the adjusting nut 24 and the support block 221 of the annular compression seat 22, and the design of the annular cushion block 28 avoids the direct contact between the adjusting nut 24 and the support block 221, avoids the abrasion of the support block 221 and prolongs the service life of the support block 221; the swing hole 223 is formed in an inverted cone shape, and the angle adjustment range of the pressing rod 23 is expanded.

Finally, it should be noted that: while there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. An improved cervical retractor, comprising: comprises a retractor body and a carotid artery compressor;

the tractor body comprises a front neck support frame and a rear traction neck support, and the front neck support frame is connected with the rear traction neck support through a hanging buckle;

the end face of the rear traction neck brace, which is contacted with the neck of a human body, is provided with a plurality of longitudinal air columns, and two adjacent longitudinal air columns are connected through at least one transverse air column; the longitudinal air column near one end of the rear traction neck support is connected with an exhaust pipe, and the exhaust pipe is provided with an exhaust valve; the longitudinal air column near the other end of the rear traction neck support is connected with an air inlet pipeline, the air inlet end of the air inlet pipeline is connected with a heating temperature control device, and an air throttle is arranged on the air inlet pipeline; the air inlet end of the heating temperature control device is connected with the air charging bag through an air pipe, and an air inlet valve is arranged on the air pipe;

the carotid artery compressor is arranged on one side of the retractor body and comprises a shell, a rotary annular column, an inner support column and a compression rod, wherein symmetrically arranged bearing beams are fixedly arranged in the shell, bearings are arranged on one opposite sides of the bearing beams and connected with the rotary annular column, the inner wall of the rotary annular column is in threaded connection with the outer wall of the inner support column, and the compression rod is rotatably arranged in the inner support column;

the middle part of the compression rod is spherical, compression balls are arranged at two ends of the compression rod, an inlet swing angle hole, an annular spherical surface and an outlet swing angle hole which are communicated with each other are arranged in the inner support column, the compression rod sequentially penetrates through the inlet swing angle hole, the annular spherical surface and the outlet swing angle hole, and the middle part of the compression rod is arranged in the annular spherical surface and is in sliding connection with the annular spherical surface;

the carotid artery compressor further comprises two stabilizing devices, wherein the two stabilizing devices are symmetrically arranged in the shell and comprise a screw rod, a nut, a wedge-shaped sliding block and a tension spring, one end of the screw rod is fixedly connected with the shell, the nut is arranged at the other end of the screw rod, the wedge-shaped sliding block is sleeved on the screw rod and is in sliding connection with the screw rod, one end of the tension spring is fixed on the inner wall of the shell, the other end of the tension spring is connected with the wedge-shaped sliding block, the inner wall of the outlet swing angle hole is conical, and the wedge-shaped sliding block can be attached to the outlet swing angle hole.

2. The improved cervical retractor of claim 1 wherein: the front neck support frame comprises a front neck support, a lower jaw bone support, two support rods and two telescopic rods, the two support rods are symmetrically arranged at the shoulder positions at the left end and the right end of the front neck support, and the two ends of the lower jaw bone support are respectively hinged with the upper ends of the two support rods; the lower ends of the two telescopic rods are hinged with the chest position of the front neck support, the two telescopic rods are arranged in bilateral symmetry, and the upper ends of the two telescopic rods are hinged with the front part of the lower jaw bone support.

3. The improved cervical retractor of claim 2 wherein: the telescopic rod comprises a first screw rod, a sleeve and a first supporting rod, the lower end of the first supporting rod is hinged to the front neck support, the upper end of the first supporting rod is rotatably connected with the lower end of the sleeve, a threaded hole with an opening in the upper end is longitudinally formed in the sleeve, the lower end of the first screw rod is in threaded connection with the threaded hole of the sleeve, and the upper end of the first screw rod is hinged to the lower jaw support.

4. The improved cervical retractor of claim 3 wherein: the lower end of the sleeve is provided with a counter bore groove, a first bearing is fixedly arranged in the counter bore groove, and the upper end of a first support rod is embedded in an inner ring of the first bearing; and a counter bore groove of the sleeve is provided with an annular step sealing cover, the annular step sealing cover penetrates through the first support rod to be connected with the lower end of the sleeve, and an annular step of the annular step sealing cover is in close contact with the first bearing.