CN219288199U

CN219288199U - Rice straw chopper

Info

Publication number: CN219288199U
Application number: CN202320089985.4U
Authority: CN
Inventors: 汤善忠
Original assignee: Weifang Feiyue Industry And Trade Co ltd
Current assignee: Weifang Feiyue Industry And Trade Co ltd
Priority date: 2023-01-31
Filing date: 2023-01-31
Publication date: 2023-07-04
Anticipated expiration: 2033-01-31

Abstract

The utility model discloses a rice straw chopper, which comprises a chopper bracket, wherein a chopping cavity is arranged in the middle of the chopper bracket, a fixed cutter assembly is arranged in the chopper bracket near the lower position of the chopper bracket, a movable cutter assembly is rotatably arranged in the chopper bracket, the movable cutter assembly is matched with the fixed cutter assembly to chop crop straws, and a grass discharging cover assembly is movably arranged on the chopper bracket near a discharge hole of the chopper bracket; the utility model has simple integral structure and convenient use, can be installed on a rice combine harvester, and can cut the straw discharged outside and returned to the field, thereby preventing the straw returned to the field from being overlong.

Description

Rice straw chopper

Technical Field

The utility model belongs to the technical field of agricultural machinery, and particularly relates to a rice straw chopper.

Background

The crop rice is abandoned after harvesting, the rural areas are used for heating, cooking and feeding livestock in the past, the living standard of farmers is improved in recent years, the cooking of the cooked straws is little, instead of the cooking, the gas and the electric appliance are adopted, the crop straws are largely abandoned, the air pollution is caused by collective burning in order to avoid delaying the farming season, the effective utilization amount is little, the problem of residual straws cannot be thoroughly solved, the farming season is very tight, the straws are not treated in time, and the next season agricultural production can be influenced.

In the prior art, when harvesting rice, a rice combine harvester is used for harvesting the rice, the rice combine harvester can automatically cut, thresh and screen the rice, and the grains and the straws are classified, and the grains are conveyed into a grain tank for storage.

The existing rice combine harvester processes the straws in the following modes: one is the outward discharging and returning treatment, and the other is the bundling treatment of the straws; when the straw is discharged to the outside and returned to the field, the rice straw after threshing is discharged to the outside and laid on the ground, so that the purpose of rotary tillage is facilitated to bury the straw.

However, when the existing rice combine harvester is used for burying the straws in rotary tillage, the operation is inconvenient, the phenomenon of winding rotary tillage equipment is easy to occur, and the using effect is reduced.

Disclosure of Invention

The rice straw chopper is simple in integral structure, convenient to use, capable of being installed on a rice combine harvester, and capable of chopping the discharged and returned straws, and preventing the returned straws from being overlong.

In order to solve the technical problems, the utility model provides the following technical scheme:

the utility model provides a rice straw chopper, includes the chopper support, and the middle part of chopper support is provided with the chamber of cutting up, and the inside of chopper support is close to its below position department and is provided with the stationary knife subassembly, and movable knife subassembly and stationary knife subassembly cooperation are used for cutting up crop straw, and movable mounting has row grass lid subassembly near its discharge gate department on the chopper support.

The following is a further optimization of the above technical solution according to the present utility model:

the whole structure of the shredder support comprises two side plates which are parallel and distributed at intervals, an upper end plate is fixedly connected to the upper side of each side plate, a lower bottom plate is arranged below the two side plates, and two ends, close to the two side plates, of each lower bottom plate are fixedly connected with the corresponding side plates respectively.

Further optimizing: the fixed cutter assembly comprises two adjusting plates which are parallel and distributed at intervals, a fixed cutter mounting seat is fixedly connected between the two adjusting plates, and a plurality of fixed cutters are sequentially arranged on the fixed cutter mounting seat along the axial direction of the fixed cutter mounting seat at intervals.

Further optimizing: a hinge shaft is arranged on the two adjusting plates near one side of the adjusting plates, and the other ends of the hinge shafts are respectively hinged with the corresponding side plates; an arc groove is formed in the adjusting plate, positioning bolts are fixedly arranged at positions, close to the arc groove, of the two side plates respectively, and one end portion, far away from the side plates, of each positioning bolt penetrates through the arc groove.

Further optimizing: the movable cutter assembly comprises a movable cutter shaft, two ends of the movable cutter shaft are respectively and integrally connected with a first shaft head and a second shaft head, the first shaft head and the second shaft head are respectively and rotatably connected with corresponding side plates, a protective cover is arranged at the position, close to the second shaft head, on each side plate, and the first shaft head is in transmission connection with the peripheral driving assembly.

Further optimizing: the movable cutter shaft is provided with a plurality of movable cutter mounting seats which are spirally and alternately distributed along the outer surface of the movable cutter shaft; the movable knife is arranged on the movable knife mounting seat, and the movable knife is in positioning connection with the movable knife mounting seat through the positioning and mounting assembly.

Further optimizing: the positioning and mounting assembly comprises a fixing bolt, wherein the fixing bolt comprises a positioning end part, a positioning shaft part and a threaded shaft part which are sequentially and integrally connected from left to right.

Further optimizing: the middle part of moving the sword mount pad has seted up the installation cavity, moving the afterbody of sword and installing in the installation cavity, having seted up the mounting hole on the moving the sword mount pad, having seted up the installation locating hole on the afterbody, the interior surface shape of installation locating hole and the surface shape phase-match of location shaft portion.

Further optimizing: the grass discharging cover assembly comprises a grass blocking cover movably mounted behind the chopper support and located at the discharge hole, and an adjusting chain is arranged between the chopper support and the grass blocking cover.

Further optimizing: the grass blocking cover comprises a grass blocking upper top plate, grass blocking side plates are fixedly connected to two sides of the grass blocking upper top plate respectively, the grass blocking upper top plate is hinged to the chopper support, arc-shaped through grooves are formed in the grass blocking side plates, locking bolts are fixedly mounted at positions, close to the corresponding arc-shaped through grooves, on the side plates, and one ends, far away from the side plates, of the locking bolts penetrate through the corresponding arc-shaped through grooves.

By adopting the technical scheme, the utility model has ingenious conception and reasonable structure, can be installed on the rice combine harvester, can crush the straws discharged by the rice combine harvester, is convenient to use, and then returns the crushed straws to the field, so that the problem of overlong straws returned to the field can be avoided.

The movable cutter assembly rotates and can be used for fully smashing straw materials under the cooperation of the fixed cutter assembly, so that the movable cutter assembly is convenient to use, the problem that too long straws returned to fields appear is avoided, the position of the fixed cutter can be adjusted through adjusting the adjusting plate 21, the movable cutter assembly is convenient to use, and the use effect is improved.

And move the sword through location installation component fixed mounting on moving the sword mount pad, convenient equipment and installation to can fix a position the position of moving the sword through location installation component, avoid moving the sword and appear rocking the phenomenon on moving the sword mount pad when using, improve result of use, can increase of service life.

The utility model will be further described with reference to the drawings and examples.

Drawings

FIG. 1 is a schematic view of the overall structure of an embodiment of the present utility model;

FIG. 2 is a front view of the overall structure of an embodiment of the present utility model;

FIG. 3 is a side view of the general structure of an embodiment of the present utility model;

FIG. 4 is an enlarged view of a portion of FIG. 1 at A;

FIG. 5 is a schematic view of the structure of the movable blade in the embodiment of the utility model;

FIG. 6 is a side view of a movable blade in an embodiment of the present utility model when installed;

FIG. 7 is a cross-sectional view of a movable blade in an embodiment of the utility model;

fig. 8 is a schematic structural view of a fixing bolt according to an embodiment of the present utility model.

In the figure: 1-a shredder support; 11-side plates; 12-an upper end plate; 13-a lower plate; 2-a fixed cutter assembly; 21-an adjusting plate; 22-a fixed cutter mounting seat; 23-fixed cutter; 24-hinging shaft; 25-arc grooves; 26-positioning bolts; 3-a moving blade assembly; 31-moving the cutter shaft; 311-first spindle nose; 312-second spindle nose; 32-protecting cover; 33-a movable cutter mounting seat; 34-moving the knife; 341-blade part; 342-knife tail; 343-mounting the positioning holes; 35-fixing bolts; 351-locating the end; 352-positioning the shaft part; 353-threaded shaft portion; 36-an anti-entanglement plate; 4-a grass discharge cover assembly; 41-grass blocking cover; 411-grass blocking upper top plate; 412-grass blocking side plates; 42-adjusting the chain; 43-a first hitch base; 44-a second hitch base; 45-arc through grooves; 46-locking bolts.

Detailed Description

Examples: as shown in fig. 1-8, the rice straw chopper comprises a chopper support 1, a chopping cavity is arranged in the middle of the chopper support 1, a fixed cutter assembly 2 is arranged in the chopper support 1 and close to the lower position of the chopper support, a movable cutter assembly 3 is rotatably arranged in the chopper support 1, the movable cutter assembly 3 is matched with the fixed cutter assembly 2 to chop crop straws, and a grass discharging cover assembly 4 is movably arranged on the chopper support 1 and close to a discharge hole of the chopper support.

The front of the chopper bracket 1 is provided with a feed inlet which is communicated with the chopper cavity, and the discharge outlet is arranged at a position on the chopper bracket 1 corresponding to the feed inlet.

The rice straw chopper is arranged on the rice combine harvester, the feed inlet of the rice straw chopper is communicated with the straw discharge outlet of the rice combine harvester, and at the moment, the straw discharged by the rice combine harvester enters the chopping cavity through the feed inlet.

The movable cutter assembly 3 rotates to be used for smashing straw materials under the cooperation of the fixed cutter assembly 2, so that the straw smashing machine is convenient to use, and smashed straw is discharged through a discharge hole, so that straw returning treatment is performed.

And the grass discharging cover component 4 is movably connected with the chopper bracket 1, and then the grass discharging angle can be adjusted by adjusting the position of the grass discharging cover component 4, so that the grass discharging device is convenient to use.

The overall structure of the shredder support 1 comprises two side plates 11, wherein the two side plates 11 are arranged in parallel and at intervals, and an upper end plate 12 is arranged above the side plates 11.

The two ends of the upper end plate 12, which are close to the two side plates 11, are fixedly connected with the corresponding side plates 11 respectively.

A lower bottom plate 13 is arranged below the two side plates 11, and two ends of the lower bottom plate 13, which are close to the two side plates 11, are fixedly connected with the corresponding side plates 11 respectively.

In this embodiment, the upper end plate 12 and the lower bottom plate 13 are arc-shaped plates, the shredding cavity is arranged between the upper end plate 12 and the lower bottom plate 13 and the two side plates 11, and the movable cutter assemblies 3 rotate in the shredding cavity.

The stationary knife assembly 2 comprises two adjusting plates 21, the two adjusting plates 21 are arranged in parallel and at intervals, a stationary knife installation seat 22 is fixedly connected between the two adjusting plates 21, and a plurality of stationary knives 23 are sequentially arranged on the stationary knife installation seat 22 along the axial direction of the stationary knife installation seat at intervals.

In this embodiment, the stationary blade 23 is fixedly mounted on the stationary blade mount 22 using a bolt fastener.

In the present embodiment, the adjusting plate 21 and the fixed blade mounting seat 22 of the fixed blade assembly 2 are respectively disposed between the two side plates 11 and below the lower bottom plate 13.

A hinge shaft 24 is mounted on the two adjusting plates 21 near one side thereof, and one ends of the hinge shafts 24 away from the adjusting plates 21 are hinged with the corresponding side plates 11.

By means of the design, the two adjusting plates 21 are hinged with the corresponding side plates 11 through the hinge shafts 24, and the positions of the fixed cutter mounting seats 22 can be adjusted when the two adjusting plates 21 rotate along the hinge shafts 24, so that the positions of the fixed cutters 23 can be adjusted, and the fixed cutter is convenient to use.

An arc groove 25 is formed in one side, away from the hinge shaft 24, of the adjusting plate 21, and the arc groove 25 is formed along the moving track of the adjusting plate 21.

The two side plates 11 are respectively and fixedly provided with a positioning bolt 26 at the positions close to the arc-shaped grooves 25, and one end part of each positioning bolt 26 far away from the side plate 11 penetrates through the arc-shaped groove 25.

The positioning bolt 26 is connected with a locking nut in a threaded manner, and the locking nut can be propped against the adjusting plate 21 by rotating the locking nut, so that the position between the adjusting plate 21 and the side plate 11 is positioned, and the use is convenient.

Through grooves are respectively formed in the positions, close to the fixed cutters 23, on the lower base plate 13, and one end portion, far away from the fixed cutter mounting seat 22, of the fixed cutter 23 penetrates through the through grooves and is checked above the lower base plate 13.

By means of the design, one end part of the fixed knife 23 far away from the fixed knife installation seat 22 can penetrate through the through groove and is arranged above the lower bottom plate 13, and at the moment, the upper end of the fixed knife 23 is located in the shredding cavity, so that the cutter is convenient to use.

The movable cutter assembly 3 comprises a movable cutter shaft 31, the movable cutter shaft 31 is rotatably arranged in the chopping cavity, two ends of the movable cutter shaft 31 are respectively and integrally connected with a first shaft head 311 and a second shaft head 312, and the first shaft head 311 and the second shaft head 312 respectively penetrate through corresponding side plates 11.

The first shaft head 311 and the second shaft head 312 are rotatably connected with the corresponding side plate 11 through bearing assemblies.

In this embodiment, the bearing assembly is a prior art, and the cooperation between the bearing assembly and the first shaft head 311 and the second shaft head 312 can be used to support the moving cutter shaft 31 for rotation, which is convenient for use.

The position of the side plate 11, which is close to the second shaft head 312, is provided with a protective cover 32, and the protective cover 32 is used for protecting the joint of the side plate 11 and the second shaft head 312, so that the use effect is improved.

The outer surface of the first shaft head 311 is provided with a connecting key groove or a spline groove, and the first shaft head 311 is in transmission connection with the external driving assembly.

In this embodiment, the peripheral driving assembly is in the prior art, and can be in transmission connection with the power output shaft on the rice combine harvester through chain transmission or belt transmission.

In this way, the peripheral driving assembly is used for driving the first shaft head 311 to rotate, and the first shaft head 311 can drive the movable cutter shaft 31 to rotate, so that the use is convenient.

The movable cutter shaft 31 is provided with a plurality of movable cutter mounting seats 33, and the plurality of movable cutter mounting seats 33 are spirally and intermittently arranged along the outer surface of the movable cutter shaft 31.

The movable knife 34 is installed on the movable knife installation seat 33, and the movable knife 34 is in positioning connection with the movable knife installation seat 33 through a positioning installation assembly.

The positioning and mounting assembly includes a fixing bolt 35, and the fixing bolt 35 includes a positioning end portion 351, a positioning shaft portion 352, and a threaded shaft portion 353, which are disposed in this order from left to right.

The positioning end portion 351, the positioning shaft portion 352, and the threaded shaft portion 353 are coaxially and integrally connected.

The cross section of the positioning end 351 is regular hexagonal; the positioning shaft portion 352 has a square cross-sectional shape.

An external thread is provided on the outer surface of the threaded shaft portion 353.

The whole structure of the movable blade 34 comprises a blade part 341 and a blade tail part 342 which are sequentially arranged from top to bottom, and the blade part 341 and the blade tail part 342 are integrally connected with each other.

The middle part of the movable knife mounting seat 33 is provided with a mounting cavity, and the cross section of the mounting cavity is matched with the cross section of the knife tail 342.

The movable cutter mounting seat 33 is provided with a mounting hole, the mounting hole on one side edge of the movable cutter mounting seat 33 is a regular hexagonal hole, and the shape of the inner surface of the regular hexagonal hole-shaped mounting hole is matched with the shape of the outer surface of the positioning end 351.

The mounting hole on the other side of the mounting seat 5 is a square hole, and the cross section shape of the square hole is matched with the outer surface shape of the positioning shaft 352.

The cutter tail 342 is provided with a mounting and positioning hole 343, the shape of the inner surface of the mounting and positioning hole 343 is matched with the shape of the outer surface of the positioning shaft 352, and the mounting and positioning hole 343 penetrates through the front side surface and the rear side surface of the cutter tail 1.

In the mounting, the tail portion 342 of the movable blade 34 is first mounted in the mounting cavity of the movable blade mount 33, and then the end portion of the fixing bolt 35 is inserted from the side of the regular hexagonal hole-shaped mounting hole, and the end portion sequentially passes through the mounting positioning hole 343 and the square hole-shaped mounting hole.

At this time, the positioning end 351 is fitted into the regular hexagonal hole-shaped mounting hole, the positioning shaft 352 is matched with the inner surface of the mounting positioning hole 343, and the mounting position between the movable blade 34 and the movable blade mount 33 can be positioned by the positioning shaft 352.

And then the screw thread shaft portion 353 is connected with the screw thread, so that the movable knife 34 and the movable knife mounting seat 33 can be positioned and fixedly connected, the movable knife 344 and the movable knife mounting seat 33 are prevented from shaking, and the use effect is improved.

In this embodiment, the axial length of the mounting positioning hole 343 is greater than the axial length of the positioning shaft 352 than the axial length of the square hole-shaped mounting hole.

In this way, after the movable knife 34 is fixedly mounted on the movable knife mounting seat 33 by the fixing bolt 35, the positioning shaft portion 352 of the fixing bolt 35 can be positioned in the mounting positioning hole 343 and the square hole-shaped mounting hole, so that the movable knife 34 can be conveniently positioned.

And the side of the positioning shaft portion 352 away from the positioning end portion 351 and the outer surface of the movable cutter mounting seat 33 are provided with a spacing distance, and the connecting nut on the threaded shaft portion 353 can be conveniently screwed through the spacing distance, so that the fixing effect is improved.

By the design, the movable cutter shaft 31 can rotate to drive each movable cutter 34 on the movable cutter shaft 31 to rotate, and the movable cutters 34 rotate and can form shearing force under the cooperation of the fixed cutters 23, so that the long rice straw is chopped, and the rice straw cutter is convenient to use.

The grass baffle 36 is arranged at the position, close to the first shaft head 311 and the second shaft head 312, on the movable cutter shaft 31, respectively, and the grass baffle 36 is used for blocking impurities in the shredding cavity, so that the impurities in the shredding cavity are prevented from moving to the connection position of the first shaft head 311 and the second shaft head 312 and the side plate 11, further the risk of winding is placed, and the use effect is improved.

The grass discharging cover assembly 4 comprises a grass blocking cover 41 movably arranged behind the chopper bracket 1 and positioned at the discharge hole, and an adjusting chain 42 is arranged between the chopper bracket 1 and the grass blocking cover 41.

The whole structure of the grass blocking cover 41 comprises a grass blocking upper top plate 411, grass blocking side plates 412 are fixedly connected to two sides of the grass blocking upper top plate 411 respectively, and one side of the grass blocking upper top plate 411, which is close to the chopper bracket 1, is hinged to the chopper bracket 1 through a hinge shaft.

The two grass-blocking side plates 412 are respectively provided inside the two side plates 11.

The grass blocking upper top plate 411 is provided with a first hanging seat 43, the chopper bracket 1 is provided with a second hanging seat 44, the upper end of the adjusting chain 42 is detachably connected with the second hanging seat 44, and the lower end of the adjusting chain 42 is fixedly connected with the first hanging seat 43.

By means of the design, two ends of the adjusting chain 42 are connected with the corresponding chopper support frame 1 and the grass discharging cover assembly 4 through the first hanging seat 43 and the second hanging seat 44 respectively, and the grass discharging cover assembly is convenient to use, assemble and install.

And the grass discharging cover assembly 4 can be driven to rotate along the hinge joint of the grass discharging cover assembly 4 and the chopper bracket 1 by adjusting the length of the adjusting chain 42, so that the grass discharging cover assembly is convenient to use.

The grass blocking side plate 412 is provided with an arc-shaped through groove 45, and the arc-shaped through groove 45 penetrates through two side surfaces of the grass blocking side plate 412.

A locking bolt 46 is fixedly arranged on the side plate 11 at a position close to the corresponding arc-shaped through groove 45, and one end, far away from the side plate 11, of the locking bolt 46 penetrates through the corresponding arc-shaped through groove 45.

In the present embodiment, the position between the grass blocking side plate 412 and the side plate 11 can be positioned by tightening the locking bolt 46, which is convenient for use.

A plurality of guide plates are installed on the inner surface of the grass blocking upper top plate 411 of the grass blocking cover 41 at intervals, and the guide plates are used for guiding the discharged straws, so that the use is convenient.

When the rice straw chopper is used, the rice straw chopper is arranged on the rice combine harvester, the feed inlet of the rice straw chopper is communicated with the straw discharge outlet of the rice combine harvester, and at the moment, the straw discharged by the rice combine harvester enters the chopping cavity through the feed inlet.

Alterations, modifications, substitutions and variations of the embodiments herein will be apparent to those of ordinary skill in the art in light of the teachings of the present utility model without departing from the spirit and principles of the utility model.

Claims

1. The utility model provides a rice straw shredder, includes shredder support (1), its characterized in that: the middle part of the chopper support (1) is provided with a chopping cavity, a fixed cutter assembly (2) is arranged in the chopper support (1) near the lower position of the chopper support, a movable cutter assembly (3) is rotatably arranged in the chopper support (1), the movable cutter assembly (3) is matched with the fixed cutter assembly (2) to chop crop straws, and a grass discharging cover assembly (4) is movably arranged on the chopper support (1) near the discharge hole of the chopper support.

2. A rice straw chopper according to claim 1, wherein: the whole structure of the shredder support (1) comprises two side plates (11), wherein the two side plates (11) are arranged in parallel at intervals, an upper end plate (12) is fixedly connected to the upper side of each side plate (11), a lower bottom plate (13) is arranged below the two side plates (11), and two ends, close to the two side plates (11), of each lower bottom plate (13) are fixedly connected with the corresponding side plates (11) respectively.

3. A rice straw chopper according to claim 2, wherein: the fixed cutter assembly (2) comprises two adjusting plates (21), the two adjusting plates (21) are arranged in parallel at intervals, a fixed cutter mounting seat (22) is fixedly connected between the two adjusting plates (21), and a plurality of fixed cutters (23) are sequentially arranged on the fixed cutter mounting seat (22) along the axial direction of the fixed cutter mounting seat at intervals.

4. A rice straw chopper according to claim 3, wherein: a hinge shaft (24) is arranged on the two adjusting plates (21) near one side of the adjusting plates, and the other ends of the hinge shafts (24) are respectively hinged with the corresponding side plates (11); an arc-shaped groove (25) is formed in the adjusting plate (21), positioning bolts (26) are fixedly arranged at positions, close to the arc-shaped groove (25), on the two side plates (11), respectively, and one end portion, far away from the side plates (11), of each positioning bolt (26) penetrates through the arc-shaped groove (25).

5. The rice straw chopper according to claim 4, wherein: the movable cutter assembly (3) comprises a movable cutter shaft (31), two ends of the movable cutter shaft (31) are respectively and integrally connected with a first shaft head (311) and a second shaft head (312), the first shaft head (311) and the second shaft head (312) are respectively and rotatably connected with corresponding side plates (11), a protective cover (32) is arranged at the position, close to the second shaft head (312), on each side plate (11), and the first shaft head (311) is in transmission connection with an external driving assembly.

6. A rice straw chopper according to claim 5, wherein: a plurality of movable cutter mounting seats (33) are arranged on the movable cutter shaft (31), and the plurality of movable cutter mounting seats (33) are spirally and alternately distributed along the outer surface of the movable cutter shaft (31); the movable knife (34) is arranged on the movable knife mounting seat (33), and the movable knife (34) is in positioning connection with the movable knife mounting seat (33) through the positioning mounting assembly.

7. The rice straw chopper according to claim 6, wherein: the positioning and mounting assembly comprises a fixing bolt (35), wherein the fixing bolt (35) comprises a positioning end part (351), a positioning shaft part (352) and a threaded shaft part (353) which are sequentially and integrally connected from left to right.

8. The rice straw chopper according to claim 7, wherein: the middle part of moving sword mount pad (33) has seted up the installation cavity, install in the installation cavity moving the afterbody (342) of sword (34), set up the mounting hole on moving sword mount pad (33), set up on afterbody (342) and install locating hole (343), the interior surface shape of installation locating hole (343) matches with the surface shape of location shaft portion (352).

9. A rice straw chopper according to claim 8, wherein: the grass discharging cover assembly (4) comprises a grass blocking cover (41) movably mounted behind the cutter support (1) and located at the discharge hole, and an adjusting chain (42) is arranged between the cutter support (1) and the grass blocking cover (41).

10. A rice straw chopper according to claim 9, wherein: the grass blocking cover (41) comprises a grass blocking upper top plate (411), grass blocking side plates (412) are fixedly connected to two sides of the grass blocking upper top plate (411) respectively, the grass blocking upper top plate (411) is hinged to the chopper support (1), arc-shaped through grooves (45) are formed in the grass blocking side plates (412), locking bolts (46) are fixedly mounted at positions, close to the corresponding arc-shaped through grooves (45), on the side plates (11), and one ends, far away from the side plates (11), of the locking bolts (46) penetrate through the corresponding arc-shaped through grooves (45).