The present disclosure relates to the technical field of fastener, especially to a fastener.
Among the commonly used fasteners, a preload is applied to the threaded fastener, the nuts and bolts (or stud, screw) will generate a relative angular displacement with the axis of the helix on the bolt, caused by various reasons such as displacement, creepage, vibration, impact of external force, etc. between the fastener and the fastened objects. The relative angular displacement of the screw pair will produce axial displacement at the same time, resulting in loosening of the threaded fastener and a reduction in the preload of the fastened objects.
The present disclosure aims to provide a fastener system to address the problem of corresponding axial displacement of the relative angular displacement of the screw pair in some threaded fastener systems.
The fastener comprises a body, a damper and a restraint. The body is provided with a coupling part, which comprises a plurality of discontinuous raised ribs going around an outer surface of the coupling part. The damper is fitted over the coupling part. A plurality of grooves go around an inner surface of the damper. The plurality of raised ribs are fitted to the grooves. The restraint is arranged to surround the damper, so the restraint may restrict the damper in a proper certain position range of the body.
In some embodiment, the fastener further comprises a supporting part. The supporting part is arranged adjacent to the body. A first end of the supporting part is abutted against to the fastened object, and a second end of the supporting part, which is opposite to the first end, is abutted against to the damper.
In some embodiment, the damper comprises at least two clamping parts. The plurality of groove is consisted of a plurality of annular recess on the at least two clamping parts. The annular recesses are discontinuous.
In some embodiment, the damper is consisted of two symmetrical clamping parts.
In some embodiment, a cross section of the raised rib is semicircle-shaped, triangular, rectangular, trapezoidal, or jagged.
In some embodiment, the body comprises a head. At least one side of the head is provided with the coupling part. A horizontal width of the head is greater than the one of the body.
In some embodiment, the head and the body are integrated in one piece, wherein the head is located at one end of the body. The body and the head both are cylindrical. A diameter of the head is greater than the one of the body.
In some embodiment, the fastener further comprises a supporting part. The supporting part is arranged adjacent to the body. A first end of the supporting part is abutted against to the fastened object, and a second end of the supporting part, which is opposite to the first end, is abutted against to the damper or the head.
In some embodiments, the damper is cylindrical, the restraint is ring-shaped, and the restraint is fitted over the damper.
In some embodiments, the coupling part is cylindrical or conical.
The present disclosure provides the following advantages:
The axial displacement is restricted when a relative angular displacement is generated during the damper around the central axis.
FIG.1 is a schematic diagram of the fastener (in the example of a bolt);
IN the drawings: 1. bolt; 2. damper; 3. Restraint; 4. supporting part; 5. first fastened object; 6. second fastened object.
The following describes the embodiments of the present disclosure in detail with reference to the accompanying drawings, so that the advantages and features of the present disclosure can be more easily understood by those skilled in the art, and the protection scope of the present disclosure is more clearly defined.
Please refer to
In the embodiment, the body 11 is cylindrical. A first end of the body comprises a coupling part, and a second end of the body comprise a head which is cylindrical. The diameter of the head is greater than the diameter of the body. The body 11 with a head 12 defines the bolt 1. The body 11 and the head 12 may be integrated into one piece, or may be secured together by melt.
The coupling part comprises a plurality of discontinuous raised ribs going around an outer surface of the coupling part. A center axis of the raised rib 131 overlaps the enter axis of the body 11. The raised rib 131 is also known as external annular line. In the present disclosure, a cross section of the raised rib is semicircle. In some other embodiments, the cross section of the raised rib 131 may be triangular, rectangular, trapezoidal, or jagged.
The damper 2 is fitted over the coupling part 13. A groove 23 going around an inner surface of the damper 2. The groove 23 is also known as the internal annular line. The raised rib 131 is fitted to the groove 23. The damper 2 comprises at least two clamping parts 21, 22. In the embodiment, the damper 2 is consisted of two clamping parts 21, 22. A cross section of the groove 23is semicircle. In some other embodiments, the cross section of the groove 23 may be in the form of other shapes, which may depend on the shape of cross section of the raised rib 131 as long as the groove 23 is fitted to the raised rib 131.
The restraint 3 is arranged to surround the damper 2, so the restraint 3 may restrict the damper 2 in a proper certain position range of the body 11. In the embodiment, the restraint 3 is ring-shaped, which fitted over the damper 2. In some other embodiments, the restraint 3 is a clamping hoop. The clamping hoop may restrict the damper 2 by means of bolt. Other members which can restrict the damper 2 may be used.
In the present disclosure, the raised rib 131 is provided on the coupling part 13 of the body 11. The adjacent two raised ribs are spaced axially rather than arranged continuously. The axial movement of the damper 2 is limited, so the supporting part 4 is provided for compensating the gap between the damper 2 and the fastened object 5. The supporting 4 at the same time may transmit a preload that the damper 2 applied to the fastened object 4. When the first end of the fastened object is abutted against the head 12, and the second end of the fastened object remains a distance to the damper 2 while the damper 2 cannot move axially anymore, the supporting part 4 may be arranged between the fastened object 5 and the damper 2 so that the fastened object 5 will not move in range of the distance. The size of the supporting part 4 along the axis may be varied according to actual need, and may have deformation because of the preload of the damper 2 so as to apply the preload from the damper 2 onto the fastened object 5.
In the present disclosure, the supporting part 4 is a cylindrical part fitted over the body 11. The first end of the supporting part 4 is abutted against to the fastened object 5, while the second end of the supporting part 4 is abutted against to the damper 2. In some other embodiments, the first end of the supporting part 4 is abutted against to the fastened object 5, while the second end of the supporting part 4 is abutted against to the head 12. In further embodiments, the supporting part 4 may be an individual part which forms no part of the present disclosure as long as it makes up the gap between the damper 2 and the fastened object 5.
There are two manners to apply the preload onto the fastened object. In the example of the bolt, the two manners are described as follows:
1. An external stretching machine is used to apply the preload. As shown in
2. Applying force to the structure of the supporting part 4 so that the supporting part 4 generates a supporting force to the fastened object and the damper. As shown in
In the embodiments, two fastened objects are shown. But as a matter of fact, the present disclosure may apply to fasten more than two objects with the damper in proper size.
The difference between this embodiment and the embodiment 1 is that: both ends of the body of this embodiment comprise a coupling part which can fitted to the damper. The damper on one end of the body may be used as the head in the embodiment 1, and it can be used to preload objects according to the two manners described in the embodiment 1.
The above are only the embodiments of the present disclosure and do not limit the patent scope of the present disclosure. Any equivalent structure or equivalent transformation made by the description and drawings of the present disclosure, or directly or indirectly used in other related technical fields, shall be deemed within the scope of the present disclosure.
Number | Date | Country | Kind |
---|---|---|---|
201810108755.1 | Jan 2018 | CN | national |
This application is a continuation in part of International Patent Application No. PCT/CN2019/000015 with a filing date of Jan. 23, 2019, designating the United States, now pending, and further claims priority to Chinese Patent Application No. 201810108755.1 with a filing date of Jan. 25, 2018. The content of the aforementioned applications, including any intervening amendments thereto, are incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
Parent | PCT/CN2019/000015 | Jan 2019 | US |
Child | 16935336 | US |