CN213479590U

CN213479590U - Site survey device that building engineering cost was used

Info

Publication number: CN213479590U
Application number: CN202021878639.7U
Authority: CN
Inventors: 李维
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-09-01
Filing date: 2020-09-01
Publication date: 2021-06-18
Anticipated expiration: 2030-09-01

Abstract

The utility model discloses a site survey device that building engineering cost was used, dead lever including vertical setting, the fixed fixing base that is equipped with in dead lever upper end, the fixing base upside is equipped with accepts the board, it is connected with the fixing base through accurate adjusting part to accept the board, the fixing base downside is equipped with the three bracing piece of evenly arranging, three bracing piece lower extreme is all fixed to be equipped with to the post, the one end that the bracing piece was kept away from to the three post is all fixed and is equipped with the bar-shaped piece, the spacing post fixed connection of multistage telescopic link one end and second, the multistage telescopic link other end rotates with the bar-shaped piece to be connected, one side that the bracing piece was kept away from to the bar-shaped piece is equipped with. The utility model discloses can carry out accurate regulation in building engineering surveys, the device can carry out level and vertical rotation to surveying the appearance through carousel and connecting block simultaneously, can change the position in a flexible way, adapts to the difference and surveys the demand.

Description

Site survey device that building engineering cost was used

Technical Field

The utility model relates to a building engineering equipment field especially relates to a site survey device that building engineering cost was used.

Background

The basic content of the construction engineering survey is that the construction landform, the topography and the geology of the building are surveyed mainly by engineering measurement, hydrogeological survey and site soil property survey, so that the construction cost and the estimation budget are made, the required equipment is surveyed and recorded in the geology, topography and landform survey, the survey aims to provide engineering topography and geology basis for the basic design and construction of the stage of drawing a construction drawing of the building, and a scheme is provided for the utilization and reconstruction of the site foundation soil according to the engineering characteristics of the building and the engineering geological conditions of the foundation soil.

In current reconnaissance equipment, often appear surveying the in-process, horizontal position can not guarantee the balance and lead to surveying equipment survey data and have the deviation, and current equipment can not accurate regulation level balance simultaneously, will make the estimation result inaccurate etc. current equipment is after fixing well simultaneously, can appear inconveniently turn to the scheduling problem, turn to the messenger and just need remove equipment is whole, stability can change at the removal in-process, survey the result and will have the deviation.

To this end, we propose a site survey apparatus for construction costs to solve the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the defects existing in the prior art and providing a site survey device for construction cost.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a site survey device for construction cost comprises a fixed rod which is vertically arranged, wherein a fixed seat is fixedly arranged at the upper end of the fixed rod, a bearing plate is arranged at the upper side of the fixed seat, the bearing plate is connected with the fixed seat through a precise adjusting component, three supporting rods which are uniformly arranged are arranged at the lower side of the fixed seat, the upper ends of the three supporting rods are rotatably connected with the fixed seat, the three supporting rods are connected with the fixed rod through a limiting component, a metal ring for limiting a moving component is arranged at the lower side of the fixed rod, a limiting component for controlling the moving component is arranged on the fixed rod, supporting posts are fixedly arranged at the lower ends of the three supporting rods, a limiting rod is arranged at the lower end of the fixed rod, a first sliding block is fixedly connected at one end of the limiting rod, a first sliding groove matched with the first sliding block, four cylinders of first spacing post downside fixedly connected with, four the spacing post of one end fixedly connected with second that first spacing post was kept away from to the cylinder is three the one end of bracing piece is kept away from to the post all fixed be equipped with the bar-shaped piece, it is three all be equipped with multi-stage telescopic link between bar-shaped piece and the spacing post of second, multi-stage telescopic link one end and the spacing post fixed connection of second, the multi-stage telescopic link other end rotates with the bar-shaped piece to be connected, one side that the bracing piece was kept away from to the bar-shaped piece is equipped with the toper type stabilizer blade, be equipped with the circular recess that matches with the toper type stabilizer blade on the bar-shaped piece, be equipped with the control.

Preferably, the precise adjusting assembly comprises a fixed disk fixedly arranged on the upper side of the fixed seat, a rotary disk is arranged on the upper side of the fixed disk, the rotary disk is coaxially and rotatably connected with the fixed disk, a first gear is arranged on the coaxially fixed sleeve of the rotary disk, a connecting rod is arranged on one side of the rotary disk, the connecting rod is rotatably connected with the rotary disk, a fluted disk is coaxially and fixedly arranged on the connecting rod, a rotating handle is fixedly arranged at one end of the connecting rod away from the fluted disk, the fluted disk is meshed with the first gear, a rectangular groove is arranged on the rotary disk, a connecting block is arranged in the rectangular groove, the connecting block is fixedly connected with the bearing plate, a rotary column is arranged on the rotary disk, the rotary column penetrates through the rotary disk, the rotary column is fixedly connected with the connecting block in the rectangular groove, the rotary column, coaxial rotation is connected with the driving gear in the axis of rotation, the one end fixedly connected with second bull stick of axis of rotation is kept away from to the driving gear, driving gear and driven gear meshing, driven gear one side is equipped with the limiting plate, limiting plate one end is fixed on the carousel, limiting plate other end fixedly connected with fixed block, be equipped with first screw hole on the fixed strip, the downthehole matching of first screw is equipped with first spacing bolt, first spacing bolt lower extreme extends to in one of them teeth of a cogwheel of driven gear.

Preferably, the movable assembly comprises a circular ring sleeved on the fixed rod in a sliding manner, the circular ring is provided with three supporting strips in a rotating manner, the supporting strips are connected with a second sliding block in a rotating manner, and the supporting rods are provided with second sliding grooves matched with the second sliding blocks.

Preferably, the limiting assembly comprises a round hole arranged on the ring, a limiting bolt is arranged in the round hole in a matched mode, grooves are formed in two side walls of the round hole, abutting plates are arranged in the grooves in a sliding mode and are fixedly connected with the limiting bolt, the abutting plates are fixedly connected with the inner walls of the grooves through springs, and a plurality of limiting insertion holes matched with the limiting bolt are evenly formed in the fixing rod.

Preferably, a level gauge is fixedly arranged on the upper end face of the second limiting column.

Preferably, the control assembly includes the L type fixed block of fixed setting on the bar-shaped block lateral wall, be equipped with the grooved opening of intercommunication rectangle on the bar-shaped block lateral wall, it is connected with the second gear to rotate in L type fixed block one end, the coaxial fixedly connected with third gear of drive shaft is passed through to second gear one side, the third gear sets up in circular recess, be equipped with the rectangle fluting that corresponds with the opening on the toper type stabilizer blade lateral wall, be equipped with a plurality of tooth's sockets that match with the third gear on the grooved lateral wall of rectangle, be equipped with the second screw hole on the L type fixed block, the matching has the spacing bolt of second in the screw hole, the spacing bolt lower extreme of second extends to in one of them teeth of a cogwheel of second gear.

Compared with the prior art, the beneficial effects of the utility model are that:

1. through the observation to the spirit level, can observe the levelness of device, be convenient for observe the regulation when adjusting the fluted disc, utilize the second gear rotation of bar piece one side, drive the tapered stabilizer blade, can adjust reciprocating of tapered stabilizer blade, the regulation level of being convenient for is stable.

2. Simultaneously, the rotary table on the fixing seat is rotated and adjusted, the surveying instrument can be horizontally rotated and adjusted, the horizontal adjustment of the upper side can not influence the fixing device of the lower side when the position is fixed, and therefore the surveying efficiency is better improved.

3. Through the second bull stick that sets up on adjusting the carousel for the driving gear drives driven gear and rotates, and succinctly makes the connecting block rotate, in order to reach the rotation about surveying the appearance, has realized vertical 180 regulation, and can not influence the level assembly of downside when the upper side is adjusted, through level and vertical regulation, avoided appearing the position deviation when turning to the mobile device and the inaccurate problem of data that leads to.

Drawings

Fig. 1 is a schematic structural diagram of a site survey apparatus for construction cost according to the present invention;

fig. 2 is a schematic side view of a site survey apparatus for construction cost according to the present invention;

fig. 3 is a schematic structural diagram of a precise adjustment assembly of a site survey apparatus for construction cost according to the present invention;

fig. 4 is a schematic structural diagram of a connecting rod and its connecting components in a site survey apparatus for construction cost according to the present invention;

fig. 5 is a schematic diagram of the internal structure of a ring in a site survey apparatus for construction cost according to the present invention;

fig. 6 is the structural schematic diagram of the strip-shaped block and the connecting component thereof in the field survey device for construction cost of the utility model.

In the figure: the device comprises a fixing rod 1, a fixing seat 2, a bearing plate 3, a supporting rod 4, a fixing disk 5, a rotating disk 6, a first gear 7, a fluted disc 8, a conical supporting leg 9, a connecting block 10, a rotating column 11, a driven gear 12, a rotating shaft 13, a driving gear 14, a second rotating rod 15, a limiting plate 16, a first limiting bolt 17, a circular ring 18, a supporting strip 19, a sliding block 20, a limiting column 21, a limiting block 22, a multi-stage telescopic rod 23, a limiting bolt 24, a connecting rod 25, a limiting rod 26, a limiting bolt 27, a supporting plate 28, a fixing block 29L, a fixing block 30, a second gear 31, a third gear 31, a first limiting column 32, a rotating handle 33 and a fixing block 34.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

Referring to fig. 1-6, a site survey device for construction cost of building engineering, comprising a vertically arranged fixing rod 1, wherein the upper and lower structures can be fixed by the fixing rod 1, a fixing seat 2 is fixedly arranged at the upper end of the fixing rod 1, the upper part of the fixing seat 2 is supported by the fixing seat 2, a bearing plate 3 is arranged at the upper side of the fixing seat 2, a survey instrument is supported by the bearing plate 3 for convenient placement, the bearing plate 3 is connected with the fixing seat 2 by a precise adjusting component, the precise adjusting component comprises a fixing disk 5 fixedly arranged at the upper side of the fixing seat 2, a turntable 6 is arranged at the upper side of the fixing disk 5, the upper structure is horizontally rotated by the turntable 6, the turntable 6 is coaxially and rotatably connected with the fixing disk 5, a first gear 7 is coaxially and fixedly sleeved on the turntable 6, the upper side of the turntable 6 is driven, connecting rod 25 rotates with carousel 6 to be connected, coaxial fixed cover is equipped with fluted disc 8 on connecting rod 25, rotate through fluted disc 8 and drive first gear 7 and rotate, drive first gear 7, connecting rod 25 keeps away from the one end fixedly connected with turning handle 33 of fluted disc 8, utilize turning handle 33 to drive the fluted disc, fluted disc 8 and the meshing of first gear 7, be equipped with the rectangle fluting on carousel 6, be equipped with connecting block 10 on the rectangle fluting, utilize connecting block 10 to control rotatoryly on the rectangle fluting, connecting block 10 with accept 3 fixed connection of board, be equipped with rotary column 11 on carousel 6, utilize rotary column 11 to drive connecting block 10 and rotate, rotary column 11 runs through carousel 6.

The rotary column 11 is fixedly connected with a connecting block 10 in a rectangular groove, the rotary column 11 is rotatably connected with a rotary table 6, a driven gear 12 is fixedly sleeved on the rotary column 11, the rotary column 11 is rotated through the driven gear 12, a rotating shaft 13 is arranged on the rotary table 6, a driving gear 14 is coaxially and rotatably connected on the rotating shaft 13, power transmission is carried out through meshing of the driving gear 14 and the driven gear 12, one end of the driving gear 14, far away from the rotating shaft 12, is fixedly connected with a second rotating rod 15, the driving gear 14 is driven through the second rotating rod 15, the driving gear 14 is meshed with the driven gear 12, a limiting plate 16 is arranged on one side of the driven gear 12, the fixing block 34 can be well fixed through the limiting plate 16, one end of the limiting plate 16 is fixed on the rotary table 6, the other end of the limiting plate 16 is fixedly connected with the fixing block 34, a first threaded, the lower end of the first limiting bolt 17 extends into one of the gear teeth of the driven gear 12, and the first limiting bolt 17 is rotated into a first threaded hole to fix the driven gear 12.

2 downside of fixing base is equipped with evenly arranged three bracing piece 4, come to be connected fixing base 2 and bracing piece 4 through

bracing piece

4, 4 upper ends of three bracing piece all rotate with fixing base 2 and be connected, three bracing piece 4 is connected with dead lever 1 through removing the subassembly, it establishes ring 18 on dead lever 1 including the slip cap to remove the subassembly, can better reciprocate through ring 18, it is equipped with three 19 to support to rotate on the ring 18, it can be better to be connected ring 18 and bracing piece 4 through three 19 to support, the three one end rotation that ring 18 was kept away from to 19 is connected with second slider 20 to support, all match the second spout of second slider 20 on the three bracing piece 4, it uses with the cooperation of second spout to lead to taking off the second slider 20 that supports 19 one end, when making ring 18 reciprocate, promote bracing piece 4 to open and shut.

A metal ring for limiting the moving component is arranged at the lower side of the fixed rod 1, a limiting component for controlling the moving component is arranged on the fixed rod 1, the limiting component comprises a round hole arranged on the round ring 18, a limiting bolt 27 is arranged in the round hole in a matching way, the circular ring 18 is limited by a limiting bolt 27, grooves are arranged on both side walls of the circular ring, a resisting plate 28 is arranged in each groove in a sliding manner, the limit bolt 27 can be extended left and right through the resisting plate 28, the two resisting plates 28 are fixedly connected with the limit bolt 27, the resisting plate 28 is fixedly connected with the inner wall of the groove through a spring, a plurality of limit jacks matched with the limit bolt 27 are uniformly arranged on the fixed rod 1, the spring on one side of the resisting plate 28 performs elastic action, meanwhile, the limit bolt 27 can be acted by elasticity, so that when the limit bolt 27 is not pulled, the limit pin 27 is inserted into the limit hole to perform a horizontal fixing action to the ring 18.

The lower ends of the three support rods 4 are fixedly provided with support columns, the lower end of the fixed rod 1 is provided with a limiting rod 26, a first limiting column 32 at the lower side is connected through the limiting rod 26, one end of the limiting rod 26 is fixedly connected with a first slide block, the lower end face of the fixed rod 1 is provided with a first slide groove matched with the first slide block, the limiting rod 26 is enabled to move up and down through the first slide block and the first slide groove on the limiting rod 26, the other end of the limiting rod 26 is fixedly connected with the first limiting column 32, the lower side of the first limiting column 32 is fixedly connected with four cylinders, one ends of the four cylinders far away from the first limiting column 32 are fixedly connected with a second limiting column 21, the first limiting column 32 and the second limiting column 21 are fixedly connected through the four cylinders, one ends of the three support columns far away from the support rods 4 are fixedly provided with strip-shaped blocks 22, and multi-, the lower structure is supported and limited through a multi-stage telescopic rod 23, one end of the multi-stage telescopic rod 23 is fixedly connected with a second limiting column 21, and the other end of the multi-stage telescopic rod 23 is rotatably connected with a strip-shaped block 22;

one side of the bar-shaped block 22, which is far away from the support rod 4, is provided with a conical support leg 9, the device can be better fixed on soil through the conical support leg 9, the bar-shaped block 22 is provided with a circular groove matched with the conical support leg 9, the bar-shaped block 22 is provided with a control component for controlling the position of the conical support leg 9, the control component comprises an L-shaped fixed block 29 fixedly arranged on the side wall of the bar-shaped block 22, a second gear 30 is connected with the bar-shaped block 22 through the L-shaped fixed block 29, the side wall of the bar-shaped block 22 is provided with an opening communicated with the rectangular groove, one end of the L-shaped fixed block 29 is rotatably connected with the second gear 30, one side of the second gear 30 is coaxially and fixedly connected with a third gear 31 through a drive shaft, the second gear 30 can well drive the third gear 31 to rotate, the third gear 31 is arranged in the circular groove, the side wall of the conical support leg 9 is provided, be equipped with the second screw hole on the L type fixed block 29, the matching has second spacing bolt 24 in the screw hole, 24 lower extremes of second spacing bolt extend to in one of them teeth of a cogwheel of second gear 30, operate on the tooth's socket through third gear 31, make tapered stabilizer blade 9 reciprocate, rethread second spacing bolt 24 can fix second gear 30, it is indirect fixed with third gear 31, the fixed spirit level that is provided with of spacing post 21 up end of second, come to carry out the level observation to equipment through the observation to the spirit level, thereby adjust through third gear 31, make tapered stabilizer blade 9 adjust from top to bottom.

The working principle is as follows:

1. fixing the surveying appearance on accepting board 3, extract spacing bolt 27 earlier, the ring 18 on the dead lever 1 of recycling reciprocates, ring 18 reciprocates and drives three and supports strip 19, and then promotion second slider 20 move on the second spout, promote bracing piece 4 simultaneously and open, when opening and shutting the biggest, loosen spacing bolt 27, utilize the spring to carry out the elastic action to fixing the board 27 that supports on spacing bolt 27, make spacing bolt 27 fix in spacing downthehole, spacing bolt 27 and the cooperation of spacing jack on the ring 18 of recycling, make ring 18 fix on dead lever 1, multistage telescopic link 23 on the spacing post 21 of second when opening also can open and open along with bracing piece 4.

2. Utilize the second gear 30 rotation of bar-shaped block 22 one side to drive third gear 31 after opening, third gear 31 moves on the toothed belt simultaneously, it reciprocates to drive tapered stabilizer blade 9, through running through the upper and lower length that comes the tapered stabilizer blade 9 to the spirit level on the spacing post 21 of second, utilize second limit bolt 24 and second screw hole when the regulation finishes, in extending to the teeth of a cogwheel of second gear 30 with second limit bolt 24, fix second gear 30, in order to reach accurate regulation level effect.

3. When the reconnaissance of surveying appearance needs changing the direction simultaneously, through adjusting carousel 6 on the fixed disk 5, utilize the rotation of turning handle 33 to drive fluted disc 8, fluted disc 8 and the meshing of first gear 7 for first gear 7 rotates, thereby realizes the horizontal rotation.

4. Meanwhile, when the vertical steering is needed, the connecting block 10 on the rotary table 6 is used for driving the bearing plate 3 to vertically steer, the driving gear 14 is driven to rotate through the rotation of the second rotating rod 15, and the driving gear 14 is meshed with the driven gear 12, so that the driven gear 12 rotates to drive the coaxial rotating column 11 to rotate, the rotating column 11 rotates to drive the connecting block 10 which is fixedly connected to horizontally steer, and the horizontal steering of the surveying instrument is achieved.

5. After surveying, take out the reconnaissance appearance earlier, take out the device again from soil, outwards pull out through spacing bolt 27 to on the ring 18, make spacing bolt 27 and spacing hole part, pack up the ring 18 downwards, pack up bracing piece 4 and multi-stage telescopic rod 23 simultaneously.

The above, only be the concrete implementation of the preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art is in the technical scope of the present invention, according to the technical solution of the present invention and the utility model, the concept of which is equivalent to replace or change, should be covered within the protection scope of the present invention.

Claims

1. The on-site survey device for the construction cost comprises a vertically arranged fixed rod (1) and is characterized in that a fixed seat (2) is fixedly arranged at the upper end of the fixed rod (1), a bearing plate (3) is arranged on the upper side of the fixed seat (2), the bearing plate (3) is connected with the fixed seat (2) through an accurate adjusting component, three supporting rods (4) are uniformly arranged on the lower side of the fixed seat (2), the upper ends of the three supporting rods (4) are rotatably connected with the fixed seat (2), the three supporting rods (4) are connected with the fixed rod (1) through a limiting component, a metal ring for limiting a moving component is arranged on the lower side of the fixed rod (1), a limiting component for controlling the moving component is arranged on the fixed rod (1), supporting columns are fixedly arranged at the lower ends of the supporting rods (4), and a limiting rod (26) is arranged at the lower end of the, a first sliding block is fixedly connected to one end of the limiting rod (26), a first sliding groove matched with the first sliding block is arranged on the lower end face of the fixing rod (1), a first limiting column (32) is fixedly connected to the other end of the limiting rod (26), four cylinders are fixedly connected to the lower side of the first limiting column (32), a second limiting column (21) is fixedly connected to one end, away from the first limiting column (32), of the four cylinders, a strip-shaped block (22) is fixedly arranged at one end, away from the supporting rod (4), of each of the three support columns, a multi-stage telescopic rod (23) is arranged between each of the three strip-shaped blocks (22) and the second limiting column (21), one end of each multi-stage telescopic rod (23) is fixedly connected with the second limiting column (21), the other end of each multi-stage telescopic rod (23) is rotatably connected with the corresponding strip-shaped block (22), and a conical supporting leg (9) is arranged at one, the strip-shaped block (22) is provided with a circular groove matched with the conical support leg (9), and the strip-shaped block (22) is provided with a control assembly for controlling the position of the conical support leg (9).

2. The site survey device for the construction cost of the building engineering according to claim 1, wherein the precise adjusting component comprises a fixed disk (5) fixedly arranged on the upper side of the fixed seat (2), a rotary disk (6) is arranged on the upper side of the fixed disk (5), the rotary disk (6) is connected with the fixed disk (5) in a coaxial rotating manner, a first gear (7) is fixedly sleeved on the rotary disk (6) in a coaxial manner, a connecting rod (25) is arranged on one side of the rotary disk (6), the connecting rod (25) is connected with the rotary disk (6) in a rotating manner, a fluted disk (8) is sleeved on the connecting rod (25) in a coaxial manner, a rotating handle (33) is fixedly arranged at one end of the connecting rod (25) far away from the fluted disk (8), the fluted disk (8) is meshed with the first gear (7), a rectangular groove is formed in the rotary disk (6), and, the connecting block (10) and the board (3) of accepting are fixed connection, be equipped with rotary column (11) on carousel (6), rotary column (11) runs through carousel (6), connecting block (10) fixed connection in rotary column (11) and the rectangle fluting, rotary column (11) and carousel (6) rotate to be connected, fixed cover is equipped with driven gear (12) on rotary column (11), be equipped with axis of rotation (13) on carousel (6), coaxial rotation is connected with driving gear (14) on axis of rotation (13), the one end fixedly connected with second bull stick (15) of axis of rotation (13) is kept away from to driving gear (14), driving gear (14) and driven gear (12) meshing, driven gear (12) one side is equipped with limiting plate (16), limiting plate (16) one end is fixed on carousel (6), limiting plate (16) other end fixedly connected with fixed block (34), be equipped with first screw hole on fixed block (34), the downthehole matching of first screw hole is equipped with first limit bolt (17), first limit bolt (17) lower extreme extends to in one of them teeth of a cogwheel of driven gear (12).

3. The site survey device for construction cost according to claim 1, wherein the moving component comprises a circular ring (18) slidably sleeved on the fixing rod (1), the circular ring (18) is rotatably provided with three abutting strips (19), one ends of the three abutting strips (19) far away from the circular ring (18) are rotatably connected with a second sliding block (20), and the three supporting rods (4) are respectively matched with second sliding grooves of the second sliding block (20).

4. The site survey device for the construction cost of the building engineering according to claim 3, wherein the limiting component comprises a circular hole arranged on the circular ring (18), a limiting bolt (27) is matched in the circular hole, grooves are arranged on both side walls of the circular hole, abutting plates (28) are arranged in both grooves in a sliding manner, both abutting plates (28) are fixedly connected with the limiting bolt (27), the abutting plates (28) are fixedly connected with the inner walls of the grooves through springs, and a plurality of limiting jacks matched with the limiting bolt (27) are uniformly arranged on the fixing rod (1).

5. A site survey device for construction costs according to claim 1, characterised in that a level gauge is fixedly arranged on the upper end surface of the second restraint post (21).

6. A site survey apparatus for construction costs according to claim 1, the control component comprises an L-shaped fixed block (29) fixedly arranged on the side wall of the bar-shaped block (22), an opening communicated with the rectangular groove is arranged on the side wall of the bar-shaped block (22), one end of the L-shaped fixed block (29) is rotatably connected with a second gear (30), one side of the second gear (30) is coaxially and fixedly connected with a third gear (31) through a driving shaft, the third gear (31) is arranged in the circular groove, the side wall of the conical support leg (9) is provided with a rectangular groove corresponding to the opening, a plurality of tooth grooves matched with the third gear (31) are arranged on one side wall of the rectangular open groove, a second threaded hole is arranged on the L-shaped fixing block (29), a second limiting bolt (24) is matched and arranged in the threaded hole, the lower end of the second limiting bolt (24) extends into one gear tooth of the second gear (30).