CN112855694B - Anti-disassembly screw and machining method - Google Patents
Anti-disassembly screw and machining method Download PDFInfo
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- CN112855694B CN112855694B CN202011294868.9A CN202011294868A CN112855694B CN 112855694 B CN112855694 B CN 112855694B CN 202011294868 A CN202011294868 A CN 202011294868A CN 112855694 B CN112855694 B CN 112855694B
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- screw
- screw head
- disassembly
- stress
- positioning groove
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- 238000000034 method Methods 0.000 title claims abstract description 17
- 238000003754 machining Methods 0.000 title claims abstract description 6
- 230000007704 transition Effects 0.000 claims description 13
- 238000001125 extrusion Methods 0.000 claims description 9
- 238000007789 sealing Methods 0.000 claims description 7
- 238000005096 rolling process Methods 0.000 claims description 6
- 238000010008 shearing Methods 0.000 claims description 6
- 238000009713 electroplating Methods 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 238000010791 quenching Methods 0.000 claims description 4
- 230000000171 quenching effect Effects 0.000 claims description 4
- 238000005496 tempering Methods 0.000 claims description 4
- 238000005255 carburizing Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000004381 surface treatment Methods 0.000 claims description 3
- 230000007547 defect Effects 0.000 abstract description 2
- 238000003672 processing method Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B23/00—Specially shaped nuts or heads of bolts or screws for rotations by a tool
- F16B23/0007—Specially shaped nuts or heads of bolts or screws for rotations by a tool characterised by the shape of the recess or the protrusion engaging the tool
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B41/00—Measures against loss of bolts, nuts, or pins; Measures against unauthorised operation of bolts, nuts or pins
- F16B41/005—Measures against unauthorised operation of bolts, nuts or pins
Abstract
The invention discloses a disassembly-preventing screw and a machining method thereof, aiming at solving the defect of poor disassembly-preventing performance of the existing disassembly-preventing screw. The screw head comprises a stud and a screw head, wherein a slot is arranged on the end face of the screw head, a plurality of positioning grooves are arranged on the edge of the slot on the end face of the screw head, the side walls of the positioning grooves comprise a stress surface, a slip surface and an avoiding surface, the slip surface and the stress surface are oppositely arranged, the avoiding surface is connected between the stress surface and the slip surface, and the slip surface is obliquely arranged from bottom to top in the direction far away from the stress surface. The anti-disassembly screw with the structure has good anti-disassembly performance.
Description
Technical Field
The invention relates to a screw structure, in particular to an anti-disassembly screw and a processing method.
Background
In order to meet the emission requirements of the six national engines, the connecting structure of the crankcase part of the engine is required to be not detachable, so that the anti-detaching screw is required to be used for connection. At present, the anti-disassembly screws on the market are various, but the anti-disassembly performance of the anti-disassembly screws is poor.
Disclosure of Invention
The invention overcomes the defect of poor disassembly resistance of the existing disassembly-resistant screw, and provides the disassembly-resistant screw and the processing method thereof.
In order to solve the technical problems, the invention adopts the following technical scheme: the utility model provides an anti-disassembly screw, includes double-screw bolt, screwhead, and the screwhead is circular structure, is equipped with the slot on the screwhead terminal surface, and slot edge is equipped with a plurality of constant head tanks on the screwhead terminal surface, and the constant head tank lateral wall includes the stress surface, the face of skidding, dodges the face, and the face of skidding sets up with the stress surface is relative, dodges the face and connects between the stress surface and the face of skidding, and the face of skidding is from up keeping away from stress surface direction spiral rising down.
When the anti-disassembly screw is screwed down, the end part of the screwing tool is inserted into the slot, the edge of the end part of the screwing tool is correspondingly provided with a bulge with a positioning groove, the bulge is inserted into the positioning groove, a certain gap is reserved between the bulge and the avoiding surface, and the bulge is abutted to the stressed surface in the screw tightening process, so that the screw is not slipped. When the tightening tool rotates reversely, the bulge does not support a stress point, the end part slides over the sliding surface and is ejected outwards by the sliding surface arranged in the spiral lifting way, so that the screw is prevented from being unscrewed reversely, and the screw can be prevented from being disassembled. The anti-disassembly screw with the structure has good anti-disassembly performance.
Preferably, the slip surface is of an outer convex arc-shaped curved surface structure. The slip surface of the convex arc-shaped curved surface structure is more smooth, so that the end surface of the screwing tool can more easily slip over the slip surface, and the anti-disassembly effect of the screw is improved.
Preferably, the slipping surface comprises a guide section and an extrusion section, the edge of the guide section is connected with the edge of the avoidance surface, the extrusion section inclines from bottom to top and is radially outwards twisted along the inclined direction, and the guide section gradually gathers together from bottom to top.
When the tightening tool rotates reversely, the guide section guides the end part of the tightening tool in the spiral direction, so that the end part of the tightening tool slides out of the positioning groove outwards along the spiral direction; the extrusion section makes the end of the tightening tool slide upward off the positioning slot more easily.
Preferably, the avoiding surface is of an arc structure, and the arc avoiding surface is arranged to be far away from the center of the screw head from the connecting end with the stress surface to the connecting end with the slipping surface. The avoiding surface arranged by the structure enables the protrusion on the tightening tool to be inserted into the positioning groove, and a hollow area is formed between the end part of the protrusion and the avoiding surface. When the tightening tool rotates reversely, the distance between the outer end of the protrusion and the avoiding surface is increased continuously, the outer end of the protrusion does not contact with the avoiding surface to form a stress point, and the anti-disassembly performance of the screw is improved.
Preferably, the stress surface, the slipping surface, the avoiding surface and the bottom surface of the positioning groove are in smooth transition, and the stress surface and the slipping surface and the avoiding surface are in smooth transition.
The smooth transition of the connecting position avoids the formation of stress points, so that the screwing tool can reliably slide away when reversely rotating through the connecting position.
Preferably, the upper end profile of each positioning groove is of a C-shaped structure, the lower end profile of each positioning groove is of an S-shaped structure, the slipping surface of one positioning groove in every two adjacent positioning grooves is connected with the stress surface of the other positioning groove, and the slipping surface and the stress surface are in smooth transition; a V-shaped terminal is formed between two adjacent positioning grooves on the end face of the screw head, one side of the terminal is the upper edge of the sliding surface, and the other side of the terminal is the upper edge of the stress surface.
The positioning grooves are arranged at the edges of the slots in an end-to-end mode, so that materials are saved, and stress points are not easily formed when the screwing tool rotates reversely. The terminal on the screw head terminal surface is favorable to guaranteeing the bearing capacity of stress surface, prevents that the in-process stress surface intensity of screw tightening from taking place deformation inadequately.
Preferably, the force-bearing surface is parallel to the screw head axis. The stress surface arranged by the structure is convenient to process, has large bearing capacity and is not easy to deform.
Preferably, the relief surface is parallel to the screw head axis. The avoidance surface arranged by the structure is not easy to contact with a tightening tool.
Preferably, the bottom surface of the slot is of a concave conical structure. The bottom surface of the slot arranged by the structure is convenient to process.
A processing method of an anti-disassembly screw is used for processing the anti-disassembly screw and comprises the following steps: a. shearing materials, namely shearing a blank with a proper length according to the size specification of the anti-disassembly screw; b. forming the stud, namely forming and processing the blank to complete the forming of the stud; c. preforming a screw head, namely upsetting and preforming the screw head end of the blank; d. forming the screw head, namely directly extruding the head end of the screw by adopting a cold heading die punch rod to form a slot and a positioning groove on the surface of the screw head so as to finish the forming of the screw head; e. thread rolling, namely machining threads on the surface of the stud by adopting a thread rolling method; f. performing heat treatment, namely performing quenching and tempering or carburizing treatment on the screw head; g. and surface treatment, namely electroplating and sealing agent treatment are carried out on the screw, so that the surfaces of the slot and the positioning groove of the screw are covered with an electroplated layer and a sealing layer.
The screw head end of the screw is directly formed by adopting a cold heading die punch rod, so that the waste of materials is reduced, the cost is reduced, and the size stability of the slot and the positioning groove can be ensured. The screw head is processed by quenching and tempering and electroplating, which is beneficial to improving the strength, so that the stress surface can bear larger torque without slipping when the screw is screwed by a screwing tool. The positioning groove surface treated by the electroplating and the sealing agent has good lubricity, so that the tightening tool is easy to slide away from the positioning groove when being reversed.
Compared with the prior art, the invention has the beneficial effects that: (1) the anti-disassembly performance of the anti-disassembly screw is good; (2) the anti-disassembly screw is convenient to process and low in cost.
Drawings
FIG. 1 is a schematic diagram of an embodiment of the present invention;
FIG. 2 is a cross-sectional view of the present invention;
FIG. 3 is a top view of the present invention;
in the figure: 1. the bolt comprises a bolt body 2, a screw head 3, a slot 4, a positioning groove 5, a stress surface 6, a sliding surface 7, an avoiding surface 8, a guide section 9, an extrusion section 10, a terminal 11, a transition surface 12, a tightening tool 13, a protrusion 14 and a hollow area.
Detailed Description
The technical scheme of the invention is further described in detail by the following specific embodiments in combination with the attached drawings:
example 1: the utility model provides an anti-disassembly screw (see attached drawing 1 to attached drawing 3), including double-screw bolt 1, screwhead 2, the screwhead is circular structure, be equipped with slot 3 on the screwhead terminal surface, the slot edge is equipped with a plurality of constant head tanks 4 on the screwhead terminal surface, the constant head tank equipartition is equipped with six, the constant head tank lateral wall includes stress surface 5, the face of skidding 6, dodge face 7, it sets up with the stress surface relatively to beat the slip face, dodge the face and connect between stress surface and the face of skidding, the face of skidding is from up to keeping away from stress surface direction slope setting down. The slip surface is a convex arc-shaped curved surface structure. The sliding surface spirally rises from bottom to top in the direction far away from the stress surface. The slip surface comprises a guide section 8 and an extrusion section 9, the edge of the guide section is connected with the edge of the avoidance surface, the extrusion section inclines from bottom to top and is radially outwards twisted along the inclined direction, and the guide section gradually gathers from bottom to top. The avoiding surface is of an arc structure, and the arc avoiding surface is arranged from the connecting end with the stress surface to the connecting end with the slipping surface towards the center of the screw head. The stress surface, the slip surface, the avoidance surface and the bottom surface of the positioning groove are all in smooth transition, and the stress surface and the slip surface and the avoidance surface are all in smooth transition.
The upper end profile of each positioning groove is of a C-shaped structure, the lower end profile of each positioning groove is of an S-shaped structure, the slipping surface of one positioning groove in two adjacent positioning grooves is connected with the stress surface of the other positioning groove, and the slipping surface and the stress surface are in smooth transition; a V-shaped terminal 10 is formed between two adjacent positioning grooves on the end face of the screw head, one side of the terminal is the upper edge of a sliding surface, and the other side of the terminal is the upper edge of a stress surface. The force bearing surface is parallel to the axis of the screw head. The avoiding surface is parallel to the axis of the screw head. The bottom surface of the slot is of a concave conical structure. The upper end face of the screw head is of a plane structure, the slot is arranged on the upper end face, a transition surface 11 is arranged between the upper end face and the side face of the screw head, and the transition surface is of an outer convex arc-shaped curved surface structure.
A processing method of an anti-disassembly screw is used for processing the anti-disassembly screw and comprises the following steps: a. shearing materials, namely shearing a blank with a proper length according to the size specification of the anti-disassembly screw; b. forming the stud, namely forming and processing the blank to complete the forming of the stud; c. preforming a screw head, namely upsetting the screw head end of the blank and preforming; d. forming the screw head, namely directly extruding the head end of the screw by adopting a cold heading die punch rod to form a slot and a positioning groove on the surface of the screw head so as to finish the forming of the screw head; e. thread rolling, namely machining threads on the surface of the stud by adopting a thread rolling method; f. performing heat treatment, namely performing quenching and tempering or carburizing treatment on the screw head; g. and surface treatment, namely electroplating and sealing agent treatment are carried out on the screw, so that the surfaces of the slot and the positioning groove of the screw are covered with an electroplated layer and a sealing layer. And D, during cold heading die punch rod processing, firstly producing a female die by adopting an engraving process according to the constructed 3D model, then extruding the cold heading die punch rod by adopting a pressing process, and forming a punch head matched with the positioning groove and the slot at the end part of the cold heading die punch rod.
When the anti-disassembly screw is screwed down, the end part of the screwing tool 12 is inserted into the slot, the edge of the end part of the screwing tool and the positioning groove are correspondingly provided with the protrusions 13, the protrusions are inserted into the positioning groove, and a hollow area 14 is formed between the end part of each protrusion and the avoiding surface. The bulge is abutted to the stressed surface in the process of screwing the screw, so that the phenomenon of slipping is avoided, and the screw is screwed. When the tightening tool rotates reversely, the protrusion does not support a stress point, the distance between the outer end of the protrusion and the avoiding surface is continuously increased, the end part of the tightening tool slides over the sliding surface, and the sliding surface which is obliquely arranged is ejected outwards, so that the screw is prevented from being unscrewed reversely, and the screw can be prevented from being disassembled. The anti-disassembly screw with the structure has good anti-disassembly performance.
Example 2: the utility model provides an anti-disassembly screw, its structure is similar with embodiment 1, and the main difference lies in that the stress surface inclines to setting up to being close to the face direction that skids from bottom to top in this embodiment, and the projection of the upper edge axial direction of stress surface is placed on the face of skidding. The other structure is the same as embodiment 1. The screw of this kind of structure adopts cold-heading mould drift to directly extrude the screw head end in the course of working after, adopts the finishing impression technique to carry out the finishing impression to the stress surface and handles, forms the stress surface of slope.
When a common straight-line screw is inserted into the positioning groove, the screw can only be inserted into the slipping surface but not the bottom surface of the slot, and the slipping surface is spirally raised, so that the screw can be difficult to unscrew reversely. When the screw normally screws up the operation, the in-process that the protruding on the tightening tool inserted the constant head tank deflects to the stress surface direction, and the spiral inserts, makes protruding butt to the stress surface on, rotates the tightening tool and screws up the screw. After the screw is tightened, the tightening tool deflects in the opposite direction to cause the projection to spiral up and disengage from the positioning slot.
The above-described embodiments are merely preferred embodiments of the present invention, which is not intended to be limiting in any way, and other variations and modifications are possible without departing from the scope of the invention as set forth in the appended claims.
Claims (7)
1. An anti-disassembly screw is characterized by comprising a stud and a screw head, wherein the screw head is of a circular structure, a slot is formed in the end face of the screw head, a plurality of positioning grooves are formed in the edge of the slot in the end face of the screw head, the side wall of each positioning groove comprises a stress surface, a slip surface and an avoiding surface, the slip surface and the stress surface are arranged oppositely, the avoiding surface is connected between the stress surface and the slip surface, and the slip surface spirally rises from bottom to top in the direction away from the stress surface; the slipping surface is of an outer convex arc curved surface structure; the slipping surface comprises a guide section and an extrusion section, the edge of the guide section is connected with the edge of the avoiding surface, the extrusion section is arranged between the guide section and the stress surface, the extrusion section inclines from bottom to top and is twisted along the inclined direction radially outwards, and the guide section gradually gathers from bottom to top; the avoiding surface is of an arc structure, and the arc avoiding surface is arranged from the connecting end with the stress surface to the connecting end with the slipping surface to the center far away from the screw head.
2. The anti-disassembly screw of claim 1 wherein the stress surface, the slip surface, the avoiding surface and the bottom surface of the positioning slot are all smooth transitions, and the stress surface and the slip surface and the slipping surface and the avoiding surface are all smooth transitions.
3. The anti-disassembly screw of claim 1, wherein the upper end of the positioning groove has a C-shaped configuration, the lower end of the positioning groove has an S-shaped configuration, the sliding surface of one positioning groove of two adjacent positioning grooves is connected with the force-bearing surface of the other positioning groove, and the sliding surface and the force-bearing surface are in smooth transition; a V-shaped terminal is formed between two adjacent positioning grooves on the end face of the screw head, one side of the terminal is the upper edge of the sliding surface, and the other side of the terminal is the upper edge of the stress surface.
4. A tamper-evident screw as claimed in any one of claims 1 to 3, wherein the force-bearing surface is parallel to the axis of the screw head.
5. A tamper-evident screw as claimed in any one of claims 1 to 3, wherein the relief surface is parallel to the axis of the screw head.
6. A tamper-evident screw as claimed in any one of claims 1 to 3, wherein the base of the socket is of concave conical configuration.
7. A method for processing a disassembly-preventing screw, which is used for processing the disassembly-preventing screw of any one of claims 1 to 6, and comprises the following steps: a. shearing materials, namely shearing a blank with a proper length according to the size specification of the anti-disassembly screw; b. forming the stud, namely forming and processing the blank to complete the forming of the stud; c. preforming a screw head, namely upsetting and preforming the screw head end of the blank; d. forming the screw head, namely directly extruding the head end of the screw by adopting a cold heading die punch rod to form a slot and a positioning groove on the surface of the screw head so as to finish the forming of the screw head; e. thread rolling, namely machining threads on the surface of the stud by adopting a thread rolling method; f. performing heat treatment, namely performing quenching and tempering or carburizing treatment on the screw head; g. and surface treatment, namely electroplating and sealing agent treatment are carried out on the screw, so that the surfaces of the slot and the positioning groove of the screw are covered with an electroplated layer and a sealing layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011294868.9A CN112855694B (en) | 2020-11-18 | 2020-11-18 | Anti-disassembly screw and machining method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011294868.9A CN112855694B (en) | 2020-11-18 | 2020-11-18 | Anti-disassembly screw and machining method |
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| CN112855694A CN112855694A (en) | 2021-05-28 |
| CN112855694B true CN112855694B (en) | 2022-07-01 |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19980039944U (en) * | 1996-12-20 | 1998-09-15 | 박병재 | Special screw to prevent theft of vehicle |
| DE102008036577A1 (en) * | 2008-07-31 | 2010-02-04 | Arnold Umformtechnik Gmbh & Co. Kg | Screw driving training |
| CN201606377U (en) * | 2009-11-04 | 2010-10-13 | 浙江明泰标准件有限公司 | Anti-theft screw |
| JP5870070B2 (en) * | 2013-07-12 | 2016-02-24 | 日東精工株式会社 | Fastener with tamper-proof drive hole |
| FR3016665B1 (en) * | 2014-01-23 | 2016-08-26 | Bollhoff Otalu Sa | ELEMENT A VISSER |
| DE102015213554A1 (en) * | 2015-07-17 | 2017-01-19 | Audi Ag | screw |
| CN109807553A (en) * | 2018-12-29 | 2019-05-28 | 苏州誉高紧固系统有限公司 | One kind being used for novel pressing-riveting bolt production technology |
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Address after: No.65 yingluohe, Beilun District, Ningbo City, Zhejiang Province, 315800 Applicant after: Ningbo Minda Automobile Technology Co.,Ltd. Address before: No.65 yingluohe, Beilun District, Ningbo City, Zhejiang Province, 315800 Applicant before: NINGBO ZHENHAI MINDA ELECTROMECHANICAL CO.,LTD. |
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