CN203248487U - Injection molding screw with limited torque - Google Patents
Injection molding screw with limited torque Download PDFInfo
- Publication number
- CN203248487U CN203248487U CN 201320188305 CN201320188305U CN203248487U CN 203248487 U CN203248487 U CN 203248487U CN 201320188305 CN201320188305 CN 201320188305 CN 201320188305 U CN201320188305 U CN 201320188305U CN 203248487 U CN203248487 U CN 203248487U
- Authority
- CN
- China
- Prior art keywords
- screw
- plastic head
- plastic
- plat surface
- distance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Landscapes
- Connection Of Plates (AREA)
Abstract
The utility model relates to an injection molding screw with limited torque. The screw comprises a meal screw rod part and a plastic head part, and the screw rod part can be fastened through the design of the structure and threads. The plastic head part can comprise a broken part, the plastic head part is broken after the tightening torque reaches a value set by the design, and the rest of the plastic head part can remain on the screw. When the injection molding screw is used for being connected with and fastening an electrification part, the head portion of the screw provides a longer creepage distance in a compact space though the reasonable structural design, and therefore the function of insulation is achieved. The screw is suitable for low-voltage apparatuses, is used for being connected with and fastening the electrification parts and the plastic shell bodies of the low-voltage apparatuses, provides the creepage distance meeting the international standard requirements of related products, and well solves the problem of insulation dielectric between an energized conductor and a metal mounting back board, a DIN rail lock, other grounding components or electrified body components.
Description
Technical field
The utility model relates to a kind of screw, thereby it can prolong the effectively realization insulation of frosting creep age distance, and has torque-limiting function.More specifically, the utility model relates to a kind of torque limited injection moulding screw that is applied on the low-voltage electrical apparatus, be used for connecting with fastening low-voltage electrical apparatus in the plastic casing with electrical accessory and low-voltage electrical apparatus.
Background technique
For low-voltage electrical apparatus, requirement according to Related product international standards such as IEC60947-1 and UL489, band electric parts and grounded metal part on the loop (for example being used for installing metal lock catch, metal backing of DIN rail etc.) or other be with must keeping certain frosting creep age distance between the electrical accessory, do not punctured by surge voltage and leak electricity guaranteeing.If the low-voltage electrical apparatus volume is little, with electrical accessory and grounded metal spare approach very much, the impulse withstand voltage of product requirement is high, then adopts general design to be difficult to reach the creep age distance of standard-required, and is also breakdown easily under impulse withstand voltage.
In the design of routine, generally be connected by the plastic casing of plain screw and low-voltage electrical apparatus with electrical accessory, because the metal head of screw has certain volume, occupied a part of space, even after adding the insulating lid part, in the space of a compactness, still be difficult to accomplish enough creep age distances, enough insulating properties can not be provided.For example, be applied in the case of Pyromagnetic release at screw, the frosting creep age distance of IEC standard-required is at least 11mm, and the UL standard-required is at least 12.7mm, and the creep age distance that insulating lid can provide only is 3.7mm, well below actual demand.
In addition, the screw of prior art generally manually or by motor machine is tightened, and is tightening in the situation of a plurality of screws, can not guarantee finally screw-down torque size consistent fixedly time of each screw.In addition, in some cases, the screw after not wishing to tighten can easily unload, and the screw of prior art can not be realized this function.
The model utility content
For above-mentioned problem to be solved, the utility model proposes a kind of novel torque limited injection moulding screw, be applied to band electrical accessory and plastic casing on the link circuit.Its objective is and address the problem: 1, screw head is plastics, and by structural design, it can provide large creep age distance in very compact space, solved the impulse withstand voltage Insulation Problems.2, torque limited, when screw-down torque reached the design code value, screw head is fracture on specific cross section, thereby can guarantee even twisting moment.
According to an aspect of the present utility model, a kind of screw is provided, it comprises metal screw part and plastic head, described screw portion band is useful on fastening screw thread with being connected, and its joint and remaining in the plastic head, plastic head is T shape roughly, and has the structural design with annular groove, thereby plastic head forms the contour shape that prolongs creep age distance.
According to an aspect of the present utility model, the plastic head of a described screw side relative with screw rod forms plat surface, plastic head also comprises disconnected lower part, and this disconnected lower part is joined with a smallest cross-sectional and plat surface, when moment of torsion reaches predetermined value at this smallest cross-sectional place fracture.
According to an aspect of the present utility model, screw portion and the plastic head of screw are formed together by injection moulding.
According to an aspect of the present utility model, the described contour shape of screw is of a size of: the first distance is 5mm, and second distance is 1.5mm, and the 3rd distance is 2.2mm.
According to an aspect of the present utility model, the described smallest cross-sectional of screw is circular cross-section, and its diameter is 2mm.
According to an aspect of the present utility model, the material of the plastic head of screw is PBT.
According to an aspect of the present utility model, the material of the screw portion of screw is steel.
According to an aspect of the present utility model, the plastic head of screw has plat surface, is provided with the opening that cooperates with screw-driver on this plat surface.
According to an aspect of the present utility model, the disconnected lower part of screw has plat surface, is provided with the opening that cooperates with screw-driver on this plat surface.
Advantage of the present utility model is: the utility model is under the prerequisite that does not change small product size, the parts such as the plastic head 2 by screw, screw rod are structural design cleverly, employing has guaranteed the creep age distance (bringing up to 12.8mm from original 3.7mm) along frosting, thereby can guarantee the requirement of IEC and UL standard, guarantee the insulation under impulse withstand voltage, can tolerate the impulse withstand voltage of product requirement.In addition, this scheme ruptures when moment of torsion reaches the designing requirement value, thereby also guarantees easily screw-down torque when tightening.
Be used in various low-voltage electrical apparatuses according to torque limited injection moulding screw of the present utility model, for example be used for directly-heating thermo magnetic trip release unit, also can expand to the similar applications that other needs connect electrified body and plastic casing and require certain creep age distance.
Description of drawings
Fig. 1 is the stereogram according to first embodiment's of the utility model screw;
Fig. 2 is the sectional view of screw shown in Figure 1;
Fig. 3 is the stereogram according to second embodiment's of the utility model screw;
Fig. 4 is the sectional view of screw shown in Figure 3.
Embodiment
Hereinafter with reference to accompanying drawing, in the mode of exemplary embodiment the utility model is described, wherein, shown in each embodiment only be used for by way of example the utility model being described, should not be understood as restriction of the present utility model.In addition, the word in the expression orientation such as upper and lower, the top of using in the following description, the end, front, rear, left and right also is for convenience of explanation, but not to restriction of the present utility model.
Below with reference to Fig. 1 and 2 first embodiment of screw of the present utility model is described.Fig. 1 is the stereogram of screw 4, and Fig. 2 is the sectional view of screw shown in Figure 1.
Shown in Fig. 1-2, screw 4 of the present utility model comprises plastic head 2 and metal screw part 1, and screw portion 1 is threaded, and is used for connection and fastening, and in order to simplify view, this screw thread is not shown.Plastic head 2 is T shape roughly, and its top (when screw is put in the accompanying drawing mode) is hollow cylinder roughly, and screw rod 1 engages and remains on wherein, and the bottom has plat surface 5 and annular groove 9.Thus, plastic head 2 has the contour shape 8 that 2 usefulness thick lines represent among the figure, and this contour shape can prolong the plastics creep age distance, thereby guarantees insulation.Specifically, it comprises the first distance 6, second distance 7 and the 3rd distance 10, in a concrete case that is applied to Pyromagnetic release, the widest external diameter of plastic head 2 is 9mm, the length of plastic head longitudinal axis direction is 7mm, depth of groove is chosen for 2.2mm, thereby the first distance 6 is 5mm, second distance 7 is 1.5mm, the 3rd distance 10 is 2.2mm, and under the prerequisite that does not change the screw volume, the creep age distance of frosting has been brought up to 12.8mm from original 3.7mm, can guarantee the requirement of IEC and UL standard, guarantee the insulation under impulse withstand voltage.
Described plastic head 2 is preferably made by PBT, and screw portion 1 is made of metal, and preferably is formed from steel.Plastic head 2 and screw portion 1 are formed together by injection moulding.
As required, existing opening design in the prior art can be set on the plat surface 5, for example cross or in-line opening (not shown) so that this part can cooperate with the tightening tool such as screw-driver, thereby are screwed to the injection moulding screw on the parts that need installation.
Second embodiment below with reference to Fig. 3 and 4 pairs of screws of the present utility model is described.The stereogram of the screw 4 that Fig. 3 is, Fig. 4 are the sectional views of screw 4 shown in Figure 3.
On the first embodiment's basis, the screw head of present embodiment further comprises disconnected lower part 3, and this disconnected lower part is positioned on the plat surface 5 of plastic head 2, and is integrally formed with plastic head 2.Disconnected lower part 3 is substantial cylindrical, and its diameter is at place, the end convergent that the plat surface 5 with plastic head 2 joins, thereby itself and plat surface 5 join with smallest cross-sectional 12.According to material property, shape, applied environment etc., by the size of design smallest cross-sectional 12, under the lower part automatic trip of can realizing when moment of torsion reaches predetermined value, should breaking, and remaining part and the screw rod 1 of plastic head 2 continued to stay on the parts that are connected.Screw be applied to Pyromagnetic release with concrete case in, plastics are chosen for PBT, the diameter of smallest cross-sectional 12 is chosen for 2mm, thereby when moment of torsion reaches specified value 3Nm, disconnected lower part 3 fracture on the cross section of minimum.
The end place relative with smallest cross-sectional 12 of disconnected lower part 3 has general planar surface 11, can have the opening that cooperates with screw-driver on this general planar surface, and for example cross or yi word pattern opening are in order to be screwed to injection moulding screw 4 on the parts that need to be connected.
Describe the utility model in detail above with reference to specific embodiment of the utility model; yet it will be understood by those skilled in the art that; under the prerequisite that does not deviate from theory of the present utility model; can make multiple modification and remodeling to above-mentioned specific embodiment, and these modification and remodeling all should fall into protection domain of the present utility model.
Claims (9)
1. screw, it is characterized in that, it comprises metal screw part and plastic head, described screw portion band is useful on fastening screw thread with being connected, and it partly remains in the plastic head, plastic head is T shape roughly, and has the structural design with annular groove, thereby plastic head forms the contour shape that prolongs creep age distance.
2. screw as claimed in claim 1, it is characterized in that plastic head has plat surface in a side relative with screw rod, plastic head also comprises disconnected lower part, should disconnected lower part join smallest cross-sectional place fracture when moment of torsion reaches predetermined value with a smallest cross-sectional and plat surface.
3. screw as claimed in claim 1 or 2 is characterized in that, screw portion and plastic head are formed together by injection moulding.
4. screw as claimed in claim 2 is characterized in that, described contour shape is of a size of: the first distance is 5mm, and second distance is 1.5mm, and the 3rd distance is 2.2mm.
5. screw as claimed in claim 2 is characterized in that, described smallest cross-sectional is circular cross-section, and its diameter is 2mm.
6. screw as claimed in claim 1 or 2 is characterized in that, the material of described plastic head is PBT.
7. screw as claimed in claim 1 or 2 is characterized in that, the material of described screw portion is steel.
8. screw as claimed in claim 1 or 2 is characterized in that, plastic head has plat surface, is provided with the opening that cooperates with screw-driver on this plat surface.
9. screw as claimed in claim 2 is characterized in that, disconnected lower part has plat surface, is provided with the opening that cooperates with screw-driver on this plat surface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320188305 CN203248487U (en) | 2013-04-15 | 2013-04-15 | Injection molding screw with limited torque |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320188305 CN203248487U (en) | 2013-04-15 | 2013-04-15 | Injection molding screw with limited torque |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203248487U true CN203248487U (en) | 2013-10-23 |
Family
ID=49374927
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201320188305 Expired - Lifetime CN203248487U (en) | 2013-04-15 | 2013-04-15 | Injection molding screw with limited torque |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203248487U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105422575A (en) * | 2014-09-17 | 2016-03-23 | 美铝公司 | Fasteners With Dual Skin Depth Washers |
| CN110062604A (en) * | 2016-10-10 | 2019-07-26 | 西特尼斯Ag | Screwdriver with integrated torque protection |
-
2013
- 2013-04-15 CN CN 201320188305 patent/CN203248487U/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105422575A (en) * | 2014-09-17 | 2016-03-23 | 美铝公司 | Fasteners With Dual Skin Depth Washers |
| US9702396B2 (en) | 2014-09-17 | 2017-07-11 | Arconic Inc. | Fasteners with dual skin depth washers |
| CN110062604A (en) * | 2016-10-10 | 2019-07-26 | 西特尼斯Ag | Screwdriver with integrated torque protection |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203248487U (en) | Injection molding screw with limited torque | |
| CN203553393U (en) | Electric automobile cabinet power terminal | |
| CN101485058B (en) | Insulating element for busbars and insulating and supporting device for busbars comprising this element | |
| CN201332187Y (en) | Current-limiting cable connector | |
| CN202363601U (en) | Bidirectional spinning electric connector | |
| CN203942236U (en) | Electric circuit connection container | |
| CN103199370A (en) | Connecting piece, electronic device with connecting piece and lighting device | |
| KR200436146Y1 (en) | Support for conducting wire of a thunderbolt | |
| KR101828058B1 (en) | One-touch access devices of the switchboard busbars branch lines mastermind | |
| CN101465522B (en) | Elastic card piece connected with rectangular bus bar and shielding cover as well as bus bar insulated sleeve component | |
| CN105810462B (en) | A kind of pressure-resistant frock contact head connection structure | |
| CN207116365U (en) | Fuse and Manual maintenance switch | |
| CN203607740U (en) | Bus insulation bushing and gas insulation switch equipment using bushing | |
| CN216903634U (en) | High-voltage emergency power supply quick connecting device for environment-friendly cabinet | |
| CN203721929U (en) | Quick dismounting terminal | |
| KR101485148B1 (en) | Connector for transmitting incoming line of special high voltage substation facilities | |
| CN203983750U (en) | 1250A compound insulated bus sleeve pipe for 12kV intelligent switch | |
| CN219498251U (en) | Plastic terminal convenient to assemble | |
| CN108429020B (en) | Strong electricity single-stage connector structure | |
| CN203456605U (en) | Wire connection device | |
| CN210535881U (en) | Electric connector with long service life | |
| CN209388794U (en) | A kind of fixed small seat of insulation and insulation fixed equipment | |
| CN203909126U (en) | Novel voltage monitor | |
| CN214706607U (en) | Novel bus fixer | |
| CN202550460U (en) | Cold-contraction cable terminal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20131023 |
|
| CX01 | Expiry of patent term |