CN201276972Y - Rear expanding drilling bit and rear expanding anchor bolt matched with the same - Google Patents
Rear expanding drilling bit and rear expanding anchor bolt matched with the same Download PDFInfo
- Publication number
- CN201276972Y CN201276972Y CNU2008201230640U CN200820123064U CN201276972Y CN 201276972 Y CN201276972 Y CN 201276972Y CN U2008201230640 U CNU2008201230640 U CN U2008201230640U CN 200820123064 U CN200820123064 U CN 200820123064U CN 201276972 Y CN201276972 Y CN 201276972Y
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- expansion
- propelling
- cover
- expanding drill
- sliding mandril
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Abstract
The utility model relates to a post-reaming bit, which includes a bit assembly, a drill rod, a propelling locking component and a drill shank. The bit assembly includes a cylindrical bit frame fixed with the drill rod, the bit frame is provided with a square groove for accommodating a tip, a hole for a sliding ejector to pass through is arranged at the rear end of the square groove, the tip is fixed on the bit frame while a return spring is mounted at the front end of the tip, the propelling locking component includes a propelling component and a locking nut which is positioned at the front end of the propelling component and is capable of opening, closing and locking the propelling component, the front end of the propelling component is screwed with the drill rod while the rear end is fixed with the drill shank, and the sliding ejector is fixedly connected to the inside of the propelling component. The utility model further relates to a post-reaming anchor bolt used with the post-reaming bit, and an expansion sleeve of the post-reaming anchor bolt is composed of a reaming portion, a connecting portion and a self-undercutting portion. The post-reaming bit has the advantages of simple structure, convenient installation, simple operation, fast drilling and regular perforation, accurate size, long service life, stable expansion performance, fine anchoring effect, low cost and easy popularization.
Description
Technical field
The utility model relates to a kind of drill bit and supporting crab-bolt, especially relates to crab-bolt at the bottom of a kind of back bottom expanding drill and the supporting back expansion.
Background technology
Back anchoring is meant by boring bar tool and holes on base material or directly anchoring piece is placed accurately position of concrete by special tool(s) (as ail gun).Back anchoring can be applicable in the various engineerings, as is used for nuclear power station, power plant, subway, tunnel, basic fixed etc.; It mainly is suitable for installing and fixing as steel work, cap, suspension column, bracket and various supports, installing and fixing of template, holder suspension member, scaffold, installing and fixing of all kinds of curtain wall supports, installing and fixing of jumbo, installing and fixing of transfer system, pipeline crane span structure and guide rail, installing and fixing of railway tunnel cable, the installing and fixing of sound insulating panel such as road, railway, bridge and guardrail, the installing and fixing of other building implementss.Therefore, the status of back anchoring is more and more important in the industrial civil building engineering.Well imagining if the inefficacy of back anchor system can directly bring the loss of life and property, is necessary so adopt reliable anchor system.
Back anchoring product divides from bearing mechanism and mainly contains three kinds of friction type, mechanical caging and chemical bondings, wherein realizes that with frictional force the plavini that connects connects firm inadequately, resistance to plucking ability; Though and it is reliable to realize that with chemical adhesive the bar planting method that connects connects, its structure glue adopts chemical agent, and is easily aging, has potential safety hazard.So big outer little hole in getting out by special boring bar tool, adopt then and cut end crab-bolt after supporting and realize mechanical convex combination, reach the purpose of transmitting load after cut end technology and more and more paid attention to by people.
In recent years, a lot of research institutions have all done unremitting effort in every respect, make the back expand end product and obtained very big development, but back bottom expanding drill that adopts and supporting crab-bolt mostly are imported product at present, has following defective: (1) complex structure, product self also has support need be assembled, and transportation inconvenience, installing/dismounting bother time-consuming; (2) maybe must be installed on the dedicated water rig in use and expand (cutting) hole operation, troublesome poeration and need water just can finish reaming or must in operating process, artificially rotate product just to reach the reaming effect, cause reaming irregular easily, the operating time is long, inefficiency; (3) boring back is for need resetting cutter head about 50cm that advance earlier downwards, then could closed cutter head takes out drill bit is whole, and the punching in early stage needs default this displacement, not only uses inconvenient and influences the crab-bolt anchoring and the connection effect; (4) processing and construction cost are too high; (5) crab-bolt unstable properties, anchoring effect is poor, yielding slippage.
Summary of the invention
The purpose of this utility model provides a kind of back bottom expanding drill of easy for installation, simple to operate, pore-forming fast regular.
Another purpose of the present utility model provides that a kind of anchoring effect is good, can not be out of shape slippage when stable performance, installation, expand end crab-bolt with the matching used back of bottom expanding drill, above-mentioned back.
For reaching above-mentioned purpose, the utility model has adopted following technical scheme:
A kind of back bottom expanding drill, comprise cutter head assembly, drilling rod, advance latch assembly and drillstock, cutter head assembly is provided with the blade of a pair of edegewise, the drilling rod axle center is provided with pilot hole, the sliding mandril of the band conical surface is installed in the pilot hole, the conical surface of sliding mandril matches with the inboard knife back front end cambered surface of an above-mentioned blade, advance the displacement range of latch assembly control sliding mandril, drillstock matches with electric hammer, wherein said cutter head assembly comprise one with the fixed cylindrical knife headstock that is connected together of drilling rod, offer the cubic groove of the above-mentioned blade of a placement on the cutter head frame, groove rear end, four directions is provided with the hole of passing through for sliding mandril, the rear end of blade is fixed on the cutter head frame by fixing pin, and the blade front end is installed a back-moving spring; But described propelling latch assembly comprises propulsion assembly and the locking nut of being located at propulsion assembly front end and switch locking propulsion assembly, and described propulsion assembly front end and drilling rod are spirally connected, and rear end and drillstock are affixed, and sliding mandril is affixed with in propulsion assembly.
Back of the present utility model bottom expanding drill can also adopt following technical scheme further to realize:
Described back bottom expanding drill, wherein said propulsion assembly comprise that one advances cover, a locking part, two slide blocks and a back-up ring, and propelling puts and offers relatively that angle is the 30-60 degree between two and horizontal plane, angle is the open slot of 60-120 degree each other; One end of slide block is installed in the open slot and can slides along open slot, and the other end and locking part are affixed, and locking part and drilling rod locking can be slided in advancing cover in advancing cover and under the drive at slide block; The back-up ring block is in advancing the cover front end, and sliding mandril passes back-up ring and locking part is fixed in the rear end that advances cover.Further, advance cover outer also can sheathed one deck rubber, the protective sleeve of metal or plastic material.
Described back bottom expanding drill is installed with two keepers at interval on the wherein said drilling rod, wherein T-shaped the or rear end of rear end keeper section is arranged with bearing.
Described back bottom expanding drill, wherein said blade is L shaped, rearward end is provided with the cambered surface that matches with the conical surface of sliding mandril.
Described back bottom expanding drill, wherein said cutter head assembly and drilling rod weld or are spirally connected, and preferably are spirally connected; Described propulsion assembly and sliding mandril weld or are spirally connected, and preferably are spirally connected; Described drillstock and propulsion assembly weld or are spirally connected, and preferably are spirally connected; When being spirally connected, described sliding mandril and propulsion assembly are fixed on the solid nut of T shape locking and advance in the cover.
The utility model has also disclosed a kind of and above-mentioned back bottom expanding drill crab-bolt at the bottom of the back expansion of using that matches, comprise that the end is provided with the anchor pole of expansion cone, expansion sleeve and advances cover, the angle of expansion cone is identical with back bottom expanding drill expansion angle of release degree, wherein expansion sleeve is made up of expansion bottom, connecting portion and the bottom of autotomying, expand the bottom and join, offer 6-8 otch on it with expansion cone; Connecting portion connects the expansion bottom and the bottom of autotomying; The bottom of autotomying joins with advancing cover, and the otch of offering on it is offered otch to lack 2-4 individual than expanding the bottom.
Owing to adopted above technical scheme, made the utility model possess following technique effect:
(1) back bottom expanding drill of the present utility model, the blade front end is equiped with back-moving spring, thereby make blade put forward the closure that to reset on after reaming is finished, only needing, need not the default displacement that resets, not only more convenient to operate, and be of value to the anchoring and the connection of later stage crab-bolt, make connect more firm, cutter head assembly can be replaced when damaging simultaneously, more economically;
(2) back bottom expanding drill of the present utility model, the propelling of propulsion assembly puts and offers skewed slot, slide block drives locking part and drilling rod moves ahead, advancing cover to drive sliding mandril moves ahead, thereby making propulsion assembly rotate when pushing ahead sliding mandril advances, effectively control the gait of march of drill bit, effectively protected cutter head assembly, prolonged the application life of product;
(3) back bottom expanding drill of the present utility model, its locking nut is used for the switch locking propulsion assembly near propulsion assembly, and during locking nut locking, propulsion assembly can not advance; Only when locking nut was opened, propulsion assembly could advance sliding mandril, started cutter head assembly, thereby used safer;
(4) back bottom expanding drill of the present utility model, the keeper acting in conjunction that is provided with at interval on its drilling rod has not only guaranteed the stability of punching, can determine simultaneously the aperture and the reaming degree of depth in hole, and then obtain a more accurate hole, pore-forming fast regular, high efficiency;
(5) back bottom expanding drill of the present utility model, it advances the outer sheathed protective sleeve of cover, and front end is provided with back-up ring, drill bit can be withdrawn from the lump when not only guaranteeing recession, play the effect of inner body of protection propulsion assembly simultaneously, make its inside can not enter dust, prolong product application life;
(6) back of the present utility model bottom expanding drill, it adopts T shape lock screw to fix between sliding mandril and propulsion assembly, is more convenient for externally that tool using is used to advance the inside of cover to install, and is quick and easy for installation;
(7) back bottom expanding drill of the present utility model is simple in structure, need not the support assembling, can be directly installed on and carry out ream operation on the electric hammer, need not artificial rotation, and is easy for installation, simple to operate, high efficiency;
(8) end crab-bolt is expanded in back of the present utility model, use matches with above-mentioned back bottom expanding drill, its expansion sleeve sets up separately up and down to be autotomyed the bottom and expands the bottom, the otch of offering bottom autotomying lacks 2-4 than expanding the bottom otch, and the expansion of the bottom of autotomying will be later than the expansion time of expansion bottom, thereby has increased the anchored force of crab-bolt and the frictional force of anchored end greatly, improved the stability of crab-bolt, anchoring effect is good, and not yielding slip is difficult for being pulled out destruction.
In sum, end crab-bolt is expanded in back bottom expanding drill of the present utility model and matching used back, and is simple in structure, easy for installation, easy and simple to handle, the pore-forming fast regular, size is accurate, long service life, expansion character is stable, and anchoring effect is good, and is with low cost, is easy to popularize.
Description of drawings
Fig. 1 is the structural representation of back of the present utility model bottom expanding drill blade closure state;
Fig. 2 is the structural representation of back of the present utility model bottom expanding drill blades open state;
Fig. 3 is the structural representation that expands end crab-bolt behind the utility model.
The specific embodiment
Describe the utility model in detail below in conjunction with accompanying drawing.
Shown in attached Fig. 1 and 2, a kind of back bottom expanding drill, comprise cutter head assembly 1, drilling rod 2, locking nut 3, propulsion assembly 4 and drilling rod handle 5, cutter head assembly 1 is provided with the blade 11 of a pair of edegewise, drilling rod 2 axle center are provided with pilot hole, the sliding mandril 6 of the band conical surface 61 is installed in the pilot hole, the conical surface 61 of sliding mandril 6 matches with the inboard knife back front end cambered surface of an above-mentioned blade 11, locking nut 3 switch locking propulsion assemblies 4, the displacement range of assembly 4 control sliding mandrils 6, drillstock 5 matches with electric hammer.Wherein cutter head assembly 1 comprise one with the drilling rod 2 fixed cylindrical knife headstocks 12 that are connected together, offer the cubic groove of the above-mentioned blade of a placement on the cutter head frame 12, groove rear end, four directions is provided with the hole of passing through for sliding mandril 6, the rear end of blade 11 is fixed on the cutter head frame 12 by fixing pin 14, and blade 11 front ends are installed a back-moving spring 13.Blade 11 is L shaped, and rearward end is provided with the cambered surface that matches with the conical surface 61 of sliding mandril 6.
Described propulsion assembly 4 comprises that one advances cover 41, one locking part 42, two slide blocks 43 and back-up rings 44, advances to offer relatively on the cover 41 that angle is the 30-60 degree between two and horizontal plane, angle is the open slot of 60-120 degree each other; One end of slide block 43 is installed in the open slot and can slides along open slot, and another is welded on the locking part 42, and locking part 42 locks in advancing cover 41 with drilling rod 2 and can slide in advancing cover 41 under the drive of slide block 43; Back-up ring 44 block can be welding or are spirally connected first-selected welding in advancing cover 41 front ends; The pre-bar 6 that slides passes back-up ring 44 and locking part 42 and is spirally connected or is welded in the rear end that advances cover 41, and diagram adopts and is spirally connected, and wherein lock screw is a T shape, so that tool using is installed outside advancing cover 41.
Further, described propelling cover 41 is outer also can be overlapped if weld one deck protective sleeve 45, and protective sleeve can be rubber, metal or plastic material.
Further, be installed with at interval two keepers (21,22) on described drilling rod 2, wherein T-shaped the or rear end of rear end keeper 22 sections is arranged with bearing 23.
During operation, the drillstock 5 that the back is expanded (cutting) subdrilling head is installed on the electric hammer, is inserted in the straight hole aperture of having bored.The locking nut 3 of drill bit opened with drilling rod 2 abut against, the electric switch of closed electric hammer rotates electric hammer, and tup rotates the back and drives drill bit and rotate, and drill bit rotates the back propulsion assembly cutter head assembly 1 is opened, the operation at expansion (cutting) end can finish after.
The utility model has also disclosed a kind of and above-mentioned back bottom expanding drill crab-bolt (as shown in Figure 3) at the bottom of the back expansion of using that matches, comprise that the end is provided with the anchor pole 7 of expansion cone 71, expansion sleeve 8 and advances cover 9, the angle of expansion cone 71 is identical with back bottom expanding drill expansion angle of release degree, wherein expansion sleeve 8 is made up of expansion bottom 81, connecting portion 82 and the bottom 83 of autotomying, expand bottom 81 and join, offer 6-8 otch on it with expansion cone 71; Connecting portion 82 connects the expansion bottom 81 and the bottom 83 of autotomying; The bottom 83 of autotomying joins with advancing cover 9, and the otch of offering on it is offered otch to lack 2-4 individual than expanding bottom 81.Thereby the expansion of the bottom 83 that guarantees to autotomy forever will be early than the expansion time of expanding bottom 81, thereby increased the anchored force of crab-bolt and the frictional force of anchored end greatly, has improved the stability of crab-bolt, and anchoring effect is good, and not yielding slip is difficult for being pulled out destruction.
The above is preferred embodiment of the present utility model only, is not that the utility model is done any pro forma qualification.Any change that is equal to, modification or differentiation etc. that all those skilled in the art utilize the technical solution of the utility model that the foregoing description is made all still belong in the scope of the technical solution of the utility model.
Claims (9)
1, a kind of back bottom expanding drill, comprise cutter head assembly, drilling rod, propelling latch assembly and drillstock, cutter head assembly is provided with the blade of a pair of edegewise, the drilling rod axle center is provided with pilot hole, the sliding mandril of the band conical surface is installed in the pilot hole, and the conical surface of sliding mandril matches with the inboard knife back front end cambered surface of an above-mentioned blade, advances the displacement range of latch assembly control sliding mandril, drillstock matches with electric hammer, it is characterized in that:
Described cutter head assembly comprise one with the fixed cylindrical knife headstock that is connected together of drilling rod, offer the cubic groove of the above-mentioned blade of a placement on the cutter head frame, groove rear end, four directions is provided with the hole of passing through for sliding mandril, the rear end of blade is fixed on the cutter head frame by fixing pin, and the blade front end is installed a back-moving spring;
But described propelling latch assembly comprises propulsion assembly and the locking nut of being located at propulsion assembly front end and switch locking propulsion assembly, and described propulsion assembly front end and drilling rod are spirally connected, and rear end and drillstock are affixed, and sliding mandril is affixed with in propulsion assembly.
2, back bottom expanding drill according to claim 1 is characterized in that:
Described propulsion assembly comprises that one advances cover, a locking part, two slide blocks and a back-up ring, and propelling puts and offers relatively that angle is the 30-60 degree between two and horizontal plane, angle is the open slot of 60-120 degree each other; One end of slide block is installed in the open slot and can slides along open slot, and the other end and locking part are affixed, and locking part and drilling rod locking can be slided in advancing cover in advancing cover and under the drive at slide block; The back-up ring block is in advancing the cover front end, and sliding mandril passes back-up ring and locking part is fixed in the rear end that advances cover.
3, back bottom expanding drill according to claim 2 is characterized in that:
The outer sheathed one deck protective sleeve of described propelling cover, protective sleeve is rubber, metal or plastic material.
4, according to the arbitrary described back of claim 1-3 bottom expanding drill, it is characterized in that:
Be installed with at interval two keepers on the described drilling rod, wherein T-shaped the or rear end of rear end keeper section is arranged with bearing.
5, back bottom expanding drill according to claim 4 is characterized in that:
Described blade is L shaped, and rearward end is provided with the cambered surface that matches with the conical surface of sliding mandril.
6, according to the arbitrary described back of claim 1-3 bottom expanding drill, it is characterized in that:
Described blade is L shaped, and rearward end is provided with the cambered surface that matches with the conical surface of sliding mandril.
7, according to the arbitrary described back of claim 1-3 bottom expanding drill, it is characterized in that:
Described cutter head assembly and drilling rod weld or are spirally connected, and preferably are spirally connected; Described propulsion assembly and sliding mandril weld or are spirally connected, and preferably are spirally connected; Described drillstock and propulsion assembly weld or are spirally connected, and preferably are spirally connected.
8, back bottom expanding drill according to claim 7 is characterized in that:
Described sliding mandril and propulsion assembly are fixed on T shape lock screw and advance in the cover.
9, a kind of and above-mentioned back bottom expanding drill crab-bolt at the bottom of the back expansion of using that matches comprises that the end is provided with the anchor pole of expansion cone, expansion sleeve and advances cover, and the angle of expansion cone is identical with back bottom expanding drill expansion angle of release degree, it is characterized in that:
Expansion sleeve is made up of expansion bottom, connecting portion and the bottom of autotomying, and expands bottom and expansion cone and joins, and offers 6-8 otch on it; Connecting portion connects the expansion bottom and the bottom of autotomying; The bottom of autotomying joins with advancing cover, and the otch of offering on it is offered otch to lack 2-4 individual than expanding the bottom.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201230640U CN201276972Y (en) | 2008-10-21 | 2008-10-21 | Rear expanding drilling bit and rear expanding anchor bolt matched with the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201230640U CN201276972Y (en) | 2008-10-21 | 2008-10-21 | Rear expanding drilling bit and rear expanding anchor bolt matched with the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201276972Y true CN201276972Y (en) | 2009-07-22 |
Family
ID=40894558
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2008201230640U Expired - Lifetime CN201276972Y (en) | 2008-10-21 | 2008-10-21 | Rear expanding drilling bit and rear expanding anchor bolt matched with the same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201276972Y (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102418489A (en) * | 2011-12-15 | 2012-04-18 | 西安通源石油科技股份有限公司 | Shape correcting machine for reshaping oil-gas well sleeve |
| CN102947032A (en) * | 2010-05-07 | 2013-02-27 | 奥贝里克斯控股有限公司 | Undercutting tool |
| CN104712251A (en) * | 2015-03-16 | 2015-06-17 | 中铁第四勘察设计院集团有限公司 | Pedestal drill and method for conducting concrete structure rear anchorage through same |
| CN105275937A (en) * | 2014-07-17 | 2016-01-27 | 衢州顶点电子科技有限公司 | Novel expansion bolt |
| CN105499664A (en) * | 2016-01-18 | 2016-04-20 | 杭州斯泰新材料技术有限公司 | Drill bit and installation method of plug |
| CN108518192A (en) * | 2018-06-15 | 2018-09-11 | 焦作市恒利水文地质工程有限责任公司 | A kind of cannula cavity cuts milling device |
| CN112982406A (en) * | 2021-03-22 | 2021-06-18 | 高雷 | Concrete pouring pile machine for building engineering and use method thereof |
-
2008
- 2008-10-21 CN CNU2008201230640U patent/CN201276972Y/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102947032A (en) * | 2010-05-07 | 2013-02-27 | 奥贝里克斯控股有限公司 | Undercutting tool |
| CN102418489A (en) * | 2011-12-15 | 2012-04-18 | 西安通源石油科技股份有限公司 | Shape correcting machine for reshaping oil-gas well sleeve |
| CN105275937A (en) * | 2014-07-17 | 2016-01-27 | 衢州顶点电子科技有限公司 | Novel expansion bolt |
| CN105275937B (en) * | 2014-07-17 | 2018-12-21 | 衢州顶点电子科技有限公司 | Upset bolt |
| CN104712251A (en) * | 2015-03-16 | 2015-06-17 | 中铁第四勘察设计院集团有限公司 | Pedestal drill and method for conducting concrete structure rear anchorage through same |
| CN105499664A (en) * | 2016-01-18 | 2016-04-20 | 杭州斯泰新材料技术有限公司 | Drill bit and installation method of plug |
| CN105499664B (en) * | 2016-01-18 | 2018-07-24 | 杭州斯泰新材料技术有限公司 | A kind of installation method of drill bit and bolt |
| CN108518192A (en) * | 2018-06-15 | 2018-09-11 | 焦作市恒利水文地质工程有限责任公司 | A kind of cannula cavity cuts milling device |
| CN112982406A (en) * | 2021-03-22 | 2021-06-18 | 高雷 | Concrete pouring pile machine for building engineering and use method thereof |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20090722 |