CN113802433B

CN113802433B - A dust removal recovery unit for pitch production

Info

Publication number: CN113802433B
Application number: CN202111038034.6A
Authority: CN
Inventors: 盛青山
Original assignee: Huangshan Luzhimeng Traffic Engineering Co ltd
Current assignee: Huangshan Road Dream Construction Co.,Ltd.
Priority date: 2021-09-06
Filing date: 2021-09-06
Publication date: 2022-09-09
Anticipated expiration: 2041-09-06
Also published as: CN113802433A

Abstract

The invention discloses a dust removal and recovery device for asphalt production, which comprises a cylindrical shell, wherein a heating cavity and a waste gas cavity are arranged in the shell, a feed inlet communicated with the heating cavity is arranged on the shell, and the dust removal and recovery device is characterized in that: the waste gas chamber includes leading waste gas chamber and rearmounted waste gas chamber, leading waste gas chamber is located the top in heating chamber, and the air inlet of leading waste gas chamber and the upper end intercommunication in heating chamber, rearmounted waste gas chamber is located on the shell, be equipped with annular cooling water cavity between rearmounted waste gas chamber and the leading waste gas chamber, the gas outlet of leading waste gas chamber is through a plurality of branch air pipes and rearmounted waste gas chamber intercommunication to each branch air pipe all holds in the cooling water cavity. The invention provides a dust removal and recovery device for asphalt production, which can well cool and remove dust from high-temperature smoke dust generated by heating in the process of heating and recovering asphalt waste materials, thereby achieving the effect of dust removal.

Description

A dust removal recovery unit for pitch production

Technical Field

The invention relates to the technical field of asphalt recycling, in particular to a dust removal and recovery device for asphalt production.

Background

The waste materials of the asphalt pavement are required to be recycled after the service life of the asphalt pavement is reached, in the prior art, the waste asphalt is directly processed into new asphalt concrete after a regenerant is directly added into the old asphalt, and the asphalt waste materials are required to be heated if the asphalt in the waste materials of the asphalt pavement is required to be separated out and then used for other purposes.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art: the utility model provides a dust removal recovery unit for pitch production, its in-process to the pitch waste material heat recovery can be fine to the high temperature smoke and dust that the heating produced cool down the dust removal to the effect of dust removal.

Therefore, one object of the present invention is to provide a dust removal and recovery device for asphalt production, which comprises a cylindrical housing, wherein a heating cavity and an exhaust gas cavity are arranged in the housing, a feeding port communicated with the heating cavity is arranged on the housing, and the dust removal and recovery device is characterized in that: the waste gas chamber includes leading waste gas chamber and rearmounted waste gas chamber, leading waste gas chamber is located the top in heating chamber, and the air inlet of leading waste gas chamber and the upper end intercommunication in heating chamber, rearmounted waste gas chamber is located on the shell, be equipped with annular cooling water cavity between rearmounted waste gas chamber and the leading waste gas chamber, the gas outlet of leading waste gas chamber passes through a plurality of branch air pipes and rearmounted waste gas chamber intercommunication to each branch air pipe all holds in the cooling water cavity, be equipped with terminal gas vent on the rearmounted waste gas chamber, rearmounted waste gas intracavity is equipped with a plurality of filter layers.

The heating chamber includes that the lower extreme has the open-ended inner tube, the upper end of inner tube links to each other with the shell, be equipped with the pivot in the inner tube, the lower extreme of pivot is equipped with the carousel, form annular discharge gate between the lower terminal surface of carousel and inner tube, the upper end of pivot is worn out the shell and is linked to each other with the driver at shell top, the driver orders about the pivot and rotates or follow axial reciprocating motion, the discharge gate along vertical direction's width with the axial motion of pivot is correlated with, be equipped with the heating element who is used for heating the inner tube inner chamber in the inner tube, follow in the shell and be located the annular water pipe of one set outside the inner tube is installed to the position of discharge gate top, the bottom of annular water pipe forms annular delivery port, water in the annular water pipe flow through the delivery port and form set in the outer water curtain wall of discharge gate. Make the pitch liquid after the heating liquefaction can be thrown away the inner tube through the discharge gate through the centrifugal force effect of carousel, and make the liquefied pitch liquid of high temperature can cool off rapidly and solidify after touching the water curtain wall under the effect of water curtain wall, the pitch after this solidification is the strip to finally fall downwards under the drive of self gravity and rivers, the lower extreme opening of final follow shell breaks away from the shell, accomplish the separation to pitch and aggregate in the road surface pitch waste material from this, accomplish recycle. Meanwhile, the high-temperature liquefied asphalt is directly cooled by the water curtain wall when being thrown out of the inner barrel, so that the inner wall of the shell is not polluted by asphalt liquid.

Preferably, the rotating shaft is sleeved with a shaft sleeve, the upper end of the shaft sleeve is fixedly connected with the top of the shell, the rotating shaft is movably matched with the shaft sleeve, and when the rotating shaft drives the rotating disc to move upwards to the position where the rotating disc abuts against the lower end of the shaft sleeve, the width of the discharge port in the vertical direction is larger than zero. The rotating shaft can be well protected through the shaft sleeve, so that asphalt waste in the heating cavity can not contact the rotating shaft, and the influence of asphalt liquid on the rotating shaft is reduced.

Preferably, the outer edge of the rotating disc extends to the position below the lower end face of the inner cylinder along the radial direction, and the upper end face of the rotating disc is provided with a conical surface with the height of the central position being greater than that of the edge position. Through the design of conical surface make pitch liquid can be fine assemble towards discharge gate position, the discharge of pitch liquid of being convenient for, thereby can make the aggregate slide towards the discharge gate under the drive of conical surface when the carousel moves down along with the pivot open the discharge gate simultaneously, the aggregate of being convenient for is automatic under the effect of self gravity to be discharged.

Preferably, the heating assembly comprises a plurality of heating sheets, one side of any one heating sheet is fixedly connected with the inner side wall of the inner cylinder, the other end of the heating sheet extends along the radial direction, and all the heating sheets are sequentially arranged along the circumferential direction. Through the design of this heating plate along radial extension for the heating of the waste material is piled up more evenly in the heating chamber, improves heating efficiency, reduces the local inhomogeneous problem of separating the pitch liquid that leads to of being heated.

Preferably, a cooling water cavity is arranged above the annular water pipe in the shell and is communicated with the water pipe through one or more water supply branch pipes. The cooling water cavity through the design of elevating can make and keep comparatively stable water pressure in the water pipe to can keep continuous make the water curtain wall, outside water pressure change is to the influence of water curtain wall when this design also can direct external water pipe.

Preferably, an airflow channel is arranged in the rotating shaft, a plurality of blades are arranged in the airflow channel, and all the blades are arranged at intervals along the axial direction of the rotating shaft. The rotating shaft can be lightened by arranging the airflow channel in the rotating shaft, and the blades arranged in the rotating shaft can automatically exhaust the inner cavity of the shell along with the rotation of the rotating shaft, so that waste gas generated by heating in the inner barrel can be timely exhausted, and the deposition of asphalt particles contained in the waste gas caused by unsmooth circulation of the waste gas in the inner cavity of the shell is reduced.

Preferably, a water receiving tray is arranged below the shell, an inner ring is arranged in the water receiving tray, the inner ring divides an inner cavity of the water receiving tray into a middle cavity and an annular outer cavity, the height of the upper end face of the inner ring is smaller than that of the upper end face of the water receiving tray, the outer diameter of the inner ring is smaller than the inner diameter of the bottom of the shell, the outer diameter of the bottom of the shell is smaller than that of the water receiving tray, a plurality of water passing holes are formed in the bottom of the inner ring, and the middle cavity is communicated with the annular outer cavity through the water passing holes. Can be so that the solidification pitch after being cooled down by the water curtain wall can fall into the water collector through setting up the water collector, the aggregate also can fall into the water collector after by the inner tube that discharges in simultaneously, because pitch liquid all is the strip this moment, consequently stir banding pitch in aqueous and make strip pitch arrange the inner ring in, realize that pitch and aggregate are categorised in the screening of water collector, at this in-process because the buoyancy of water, consequently easy operation.

Preferably, a floating plate is arranged in the inner ring, the outer contour of the floating plate along the horizontal direction is matched with the inner side wall of the inner ring, and a pull rod in a vertical state is arranged on the floating plate. The floating plate can directly lift all the asphalt and finish the transportation of the asphalt after the inner ring is internally filled with the strip asphalt.

Preferably, a partition plate is arranged in the water receiving tray, the upper end face of the partition plate is higher than the upper end face of the inner ring and lower than the upper end face of the water receiving tray, a sewage cavity is formed by the partition plate and the inner side wall of the water receiving tray in a surrounding mode, and a sewage discharge port communicated with the bottom of the sewage cavity is formed in the outer side wall of the water receiving tray. Through setting up the baffle can make on the water collector liquid level floating greasy dirt etc. can be driven by timely rivers that are flowed by the surface and overflow to the sewage chamber, finally discharge through the drain, the high-efficient utilization of saving water in the water collector that this can be great.

Preferably, the driver is including being used for driving pivot pivoted rotation motor and being used for driving the pivot along axial displacement's lift cylinder, the output shaft that rotates the motor passes through the gear train and meshes with the driven tooth on the pivot lateral wall, be equipped with the shift fork on the piston rod of lift cylinder, in the annular groove on the pivot lateral wall is gone into to the shift fork card, the shift fork drives the pivot along axial motion.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

The technical scheme has the following advantages or beneficial effects: firstly, asphalt in the waste material can be in a liquefied state through heating when the pavement asphalt waste material is thrown into the inner cylinder through the feeding port so as to be convenient for recycling of the asphalt, meanwhile, high-temperature waste gas generated in the heating process is cooled through the front waste gas cavity and the branch gas pipe and is purified through the rear waste gas cavity, finally, the waste gas is well cooled and dedusted, secondly, the asphalt is continuously thrown out from the discharge port under the action of centrifugal force through the rotating turntable, at the moment, the liquid asphalt liquid touches the water curtain wall to be rapidly cooled and solidified, so that the asphalt liquid is solidified into a strip shape and finally falls into the water receiving disc, the aggregate is kept in the inner cylinder, after the separation of the asphalt liquid is completed, the discharge port is enlarged through the axial downward movement of the rotating shaft, the aggregate with larger volume also falls into the water receiving disc, and the solidified asphalt liquid is separated from the aggregate, and both can be recovered separately.

Drawings

FIG. 1 is a schematic structural diagram of a dust removal and recovery device for asphalt production according to the present invention.

Fig. 2 is a partially enlarged view of the region "a" in fig. 1.

Fig. 3 is a schematic perspective view of the present invention with the water tray removed.

Fig. 4 is a side view of fig. 3.

FIG. 5 is a schematic sectional view taken along the line "B-B" in FIG. 4.

Fig. 6 is a schematic cross-sectional view of the perspective state of fig. 5.

Fig. 7 is a partially enlarged view of the region "C" in fig. 6.

Wherein, 1, a shell; 1.1, opening at the lower end; 2. an inner barrel; 3. a rotating shaft; 4. a turntable; 5. a discharge port; 6. a heating plate; 7. an annular water pipe; 7.1, a water outlet; 8. a water curtain wall; 9. a feeding port; 10. a shaft sleeve; 11. a cooling water cavity; 12. a water supply branch pipe; 13. a pre-exhaust chamber; 14. a water pan; 15. an inner ring; 16. water passing holes; 17. a floating plate; 17.1, small holes; 17.2, a pull rod; 18. a partition plate; 19. a sewage chamber; 20. a sewage draining outlet; 21. rotating the motor; 22. a lifting cylinder; 23. a rear exhaust gas cavity; 24. a branch air pipe; 25. a terminal exhaust port; 100. a chamber is heated.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be illustrative of the invention and are not to be construed as limiting the invention.

A dust removal recovery apparatus for asphalt production according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

The first embodiment is as follows:

the invention provides a dust removal and recovery device for asphalt production, which comprises a cylindrical shell 1, wherein a heating cavity 100 and an exhaust gas cavity are arranged in the shell 1, a feed inlet 9 communicated with the heating cavity 100 is arranged on the shell 1, and the dust removal and recovery device is characterized in that: the waste gas chamber includes leading waste gas chamber 13 and rearmounted waste gas chamber 23, leading waste gas chamber 13 is located the top that heats chamber 100, and the air inlet of leading waste gas chamber 13 and the upper end intercommunication that heats chamber 100, rearmounted waste gas chamber 23 is located on the shell 1, be equipped with annular cooling water chamber 11 between rearmounted waste gas chamber 23 and the leading waste gas chamber 13, a plurality of branch air pipes 24 and rearmounted waste gas chamber 23 intercommunication are passed through to the gas outlet of leading waste gas chamber 13 to each branch air pipe 24 all holds in cooling water chamber 11, be equipped with terminal gas vent 25 on the rearmounted waste gas chamber 23, be equipped with the filter layer in the rearmounted waste gas chamber 23.

The heating cavity comprises an inner cylinder 2 with an opening at the lower end, the upper end of the inner cylinder 2 is connected with the shell 1, a rotating shaft 3 is arranged in the inner cylinder 2, a rotary disc 4 is arranged at the lower end of the rotating shaft 3, an annular discharge hole 5 is formed between the rotary disc 4 and the lower end surface of the inner cylinder 2, the upper end of the rotating shaft 3 penetrates out of the shell 1 and is connected with a driver at the top of the shell 1, the driver drives the rotating shaft 3 to rotate or reciprocate along the axial direction, the width of the discharge port 5 along the vertical direction is related to the axial movement of the rotating shaft 3, a heating component for heating the inner cavity of the inner cylinder 2 is arranged in the inner cylinder 2, an annular water pipe 7 sleeved outside the inner cylinder 2 is arranged at the position above the discharge hole 5 on the inner edge of the shell 1, the bottom of the annular water pipe 7 forms an annular water outlet 7.1, and water in the annular water pipe 7 flows out through the water outlet 7.1 to form a water curtain wall 8 sleeved outside the discharge port 5.

3 overcoat of pivot is equipped with axle sleeve pipe 10, the upper end of axle sleeve pipe 10 and the top fixed connection of shell 1, pivot 3 and axle sleeve pipe 10 clearance fit work as pivot 3 drives carousel 4 and moves up to when carousel 4 offsets with the lower extreme of axle sleeve pipe 10 the width of discharge gate 5 along vertical direction is greater than zero.

The outer edge of the rotary table 4 extends to the position below the lower end face of the inner cylinder 2 along the radial direction, and the upper end face of the rotary table 4 is provided with a conical surface with the height of the center position being greater than that of the edge position.

The heating assembly comprises a plurality of heating sheets 6, one side of any one heating sheet 6 is fixedly connected with the inner side wall of the inner barrel 2, the other end of the heating sheet 6 extends along the radial direction, and all the heating sheets 6 are sequentially arranged along the circumferential direction.

The cooling water cavity 11 is positioned above the annular water pipe 7, and the cooling water cavity 11 is communicated with the annular water pipe 7 through one or more water supply branch pipes 12.

A water pan 14 is arranged below the shell 1, an inner ring 15 is arranged in the water pan 14, the inner ring 15 divides an inner cavity of the water pan 14 into a middle cavity and an annular outer cavity, the height of the upper end surface of the inner ring 15 is smaller than that of the upper end surface of the water pan 14, the outer diameter of the inner ring 15 is smaller than the inner diameter of the bottom of the shell 1, the outer diameter of the bottom of the shell 1 is smaller than that of the water pan 14, a plurality of water through holes 16 are formed in the bottom of the inner ring 15, and the middle cavity is communicated with the annular outer cavity through the water through holes 16.

Be equipped with kickboard 17 in the inner ring 15, the equipartition has a plurality of apertures on the kickboard 17, the outer profile of kickboard 17 along the horizontal direction and the inner ring 15 inside wall phase-match, be equipped with the pull rod 17.1 that is the state of erectting on the kickboard 17.

A partition plate 18 is arranged in the water pan 14, the upper end face of the partition plate 18 is higher than the upper end face of the inner ring 15 and lower than the upper end face of the water pan 14, a sewage cavity 19 is formed by surrounding the partition plate 18 and the inner side wall of the water pan 14, and a sewage discharge outlet 20 communicated with the bottom of the sewage cavity 19 is formed in the outer side wall of the water pan 14.

In order to enable rotation of the spindle and axial movement of the spindle, existing drives may be employed to respectively enable rotation and axial movement of the spindle:

an example of a driver is:

the driver comprises a rotating motor 21 for driving the rotating shaft 3 to rotate and a lifting cylinder 22 for driving the rotating shaft 3 to move axially, an output shaft of the rotating motor 21 is meshed with a driven tooth on the outer side wall of the rotating shaft 3 through a gear set, so that the rotating shaft is driven to rotate, the piston rod in the lifting cylinder 22 can stretch axially along the rotating shaft through the telescopic motion of the piston rod in the lifting cylinder 22, and the axial motion of the rotating shaft can be realized through the connection of the piston rod and the rotating shaft. Certainly, because the pivot needs to have circumferential direction at this in-process, consequently unable direct fixed connection between piston rod and the pivot, it can adopt current shift fork structural design, form annular groove in the lateral wall undercut of pivot 3 promptly, lift cylinder 22's piston rod and the stalk portion fixed connection of shift fork, the head of shift fork forms the branching of Y font, and make this Y font branching insert in the annular groove, the branching and the annular groove sliding fit of shift fork in the pivot rotation process this moment, then can drive pivot axial motion when lift cylinder 22 during operation.

Example two of the drivers:

the driver can comprise a direct drive motor, the direct drive motor at least comprises a stator ring and a rotor ring, the stator ring is fixed with the shell 1 or the shaft sleeve 10, the rotor ring is fixed with the rotating shaft, and the stator ring extends along the axial direction of the rotating shaft to enable the axial length of the stator ring to be larger than that of the rotor ring, so that the rotating shaft can well realize circumferential rotation under the driving of the direct drive motor, meanwhile, when the rotating shaft receives external force to do axial motion, the rotor ring and the stator ring are in sliding fit and the stator ring is longer, and the rotor ring moving axially can not cause the failure of the direct drive motor. Certainly, the structure of the direct drive motor in this embodiment further includes a coil, but the structure of the direct drive motor does not make sense of understanding of this embodiment, and thus the description is not repeated.

Example three of the driver:

the driver is the same including elevator motor and rotation motor, rotate the transmission between motor and the pivot and be connected, rotate motor sliding fit simultaneously on a slide rail that sets up along the axial, elevator motor orders about to rotate the motor and follows axial displacement, rotates motor and pivot from this and follows axial synchronous motion, and final this embodiment can realize pivot axial displacement and circumferential direction.

A piston rod of the lifting cylinder 22 is provided with a shifting fork which is clamped in, and the shifting fork drives the rotating shaft 3 to move along the axial direction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Various alterations and modifications will no doubt become apparent to those skilled in the art after having read the above description. Therefore, the appended claims should be construed to cover all such variations and modifications as fall within the true spirit and scope of the invention. Any and all equivalent ranges and contents within the scope of the claims should be considered to be within the intent and scope of the present invention.

Claims

1. The utility model provides a dust removal recovery unit for pitch production, it includes shell (1) of cylinder, be equipped with heating chamber (100) and waste gas chamber in shell (1), be equipped with dog-house (9) with heating chamber (100) intercommunication on shell (1), its characterized in that: the waste gas cavity comprises a front waste gas cavity (13) and a rear waste gas cavity (23), the front waste gas cavity (13) is located above the heating cavity (100), an air inlet of the front waste gas cavity (13) is communicated with the upper end of the heating cavity (100), the rear waste gas cavity (23) is arranged on the shell (1), an annular cooling water cavity (11) is arranged between the rear waste gas cavity (23) and the front waste gas cavity (13), an air outlet of the front waste gas cavity (13) is communicated with the rear waste gas cavity (23) through a plurality of branch air pipes (24), each branch air pipe (24) is accommodated in the cooling water cavity (11), a tail end exhaust port (25) is arranged on the rear waste gas cavity (23), and a filter layer is arranged in the rear waste gas cavity;

the heating chamber comprises an inner barrel (2) with an opening at the lower end, the upper end of the inner barrel (2) is connected with a shell (1), a rotating shaft (3) is arranged in the inner barrel (2), a rotary disc (4) is arranged at the lower end of the rotating shaft (3), an annular discharge hole (5) is formed between the lower end faces of the rotary disc (4) and the inner barrel (2), the upper end of the rotating shaft (3) penetrates out of the shell (1) and is connected with a driver at the top of the shell (1), the driver drives the rotating shaft (3) to rotate or axially reciprocate, the width of the discharge hole (5) in the vertical direction is associated with the axial motion of the rotating shaft (3), a heating component for heating the inner cavity of the inner barrel (2) is arranged in the inner barrel (2), an annular water pipe (7) sleeved outside the inner barrel (2) is arranged in the shell (1) along the position above the discharge hole (5), the bottom of the annular water pipe (7) forms an annular water outlet (7.1), and water in the annular water pipe (7) flows out through the water outlet (7.1) to form a water curtain wall (8) sleeved outside the discharge hole (5).

2. The dust removal and recovery device for asphalt production according to claim 1, wherein: pivot (3) overcoat is equipped with axle sleeve pipe (10), the upper end of axle sleeve pipe (10) and the top fixed connection of shell (1), pivot (3) and axle sleeve pipe (10) clearance fit work as pivot (3) drive carousel (4) move up to when carousel (4) offset with the lower extreme of axle sleeve pipe (10) discharge gate (5) are greater than zero along the width of vertical direction.

3. The dust removal and recovery device for asphalt production according to claim 2, wherein: the outer edge of the rotary table (4) extends to the position below the lower end face of the inner cylinder (2) along the radial direction, and the upper end face of the rotary table (4) is provided with a conical surface with the height of the center position being greater than that of the edge position.

4. The dust removal and recovery device for asphalt production according to claim 3, wherein: the heating assembly comprises a plurality of heating sheets (6), one side of any one heating sheet (6) is fixedly connected with the inner side wall of the inner barrel (2), the other end of the heating sheet (6) extends along the radial direction, and all the heating sheets (6) are sequentially arranged along the circumferential direction.

5. The dust removal and recovery device for asphalt production according to claim 4, wherein: the cooling water cavity (11) is positioned above the annular water pipe (7), and the cooling water cavity (11) is communicated with the annular water pipe (7) through one or more water supply branch pipes (12).

6. The dust removal and recovery device for asphalt production according to claim 5, wherein: the water receiving plate is characterized in that a lower end opening (1.1) is formed in the bottom of the shell (1), a water receiving plate (14) is arranged below the shell (1), an inner ring (15) is arranged in the water receiving plate (14), the inner ring (15) divides an inner cavity of the water receiving plate (14) into a middle cavity and an annular outer cavity, the height of the upper end face of the inner ring (15) is smaller than that of the upper end face of the water receiving plate (14), the outer diameter of the inner ring (15) is smaller than the inner diameter of the bottom of the shell (1), the outer diameter of the bottom of the shell (1) is smaller than that of the water receiving plate (14), a plurality of water passing holes (16) are formed in the bottom of the inner ring (15), and the middle cavity is communicated with the annular outer cavity through the water passing holes (16).

7. The dust removal and recovery device for asphalt production according to claim 6, wherein: be equipped with kickboard (17) in inner ring (15), the equipartition has a plurality of apertures on kickboard (17), kickboard (17) are followed the outline of horizontal direction and inner ring (15) inside wall phase-match, be equipped with pull rod (17.1) that are the state of erectting on kickboard (17).

8. The dust removal and recovery device for asphalt production according to claim 7, wherein: be equipped with baffle (18) in water collector (14), the up end of baffle (18) is higher than the up end of inner ring (15) and is less than the up end of water collector (14), surround between the inside wall of baffle (18) and water collector (14) and form sewage chamber (19), be equipped with drain (20) with the bottom intercommunication in sewage chamber (19) on the lateral wall of water collector (14).

9. The dust removal and recovery device for asphalt production according to claim 8, wherein: the driver is including being used for driving pivot (3) pivoted rotation motor (21) and being used for driving pivot (3) along axial displacement's lift cylinder (22), the output shaft that rotates motor (21) passes through the driven tooth meshing on gear train and pivot (3) lateral wall, be equipped with the shift fork on the piston rod of lift cylinder (22), in the annular groove on pivot (3) lateral wall was gone into to the shift fork card, the shift fork drives pivot (3) along axial motion.