RU214567U1 - VANDAL-RESISTANT BREAKING NUT - Google Patents

Abstract

The utility model relates to threaded fasteners and can be used in the assembly and installation of products with protection against unauthorized disassembly.

An anti-vandal detachable nut is offered, which consists of a clamping part and a twisted part connected by a neck. A through longitudinal hole is made in the nut, in which a thread is made from the side of the clamping part, the length of which does not exceed the length of the clamping part. In this case, the diameter of the hole on the side of the twisted part is larger than the diameter of the thread. The outer surface of the clamping part consists of two surfaces of rotation, tapering from the end of the nut to the neck and located at an angle to each other, while the extreme surface has a convex arcuate shape.

The technical result, which the proposed utility model is aimed at, is to realize the purpose, as well as to provide protection against loosening of the nut due to the design.

Description

The utility model relates to threaded fasteners and can be used in the assembly and installation of products with protection against unauthorized disassembly.

Known metalwork containing the elements to be connected, a bolt, a nut and a retainer that prevents disassembly of the connection. The locking means is made in the form of at least one pin bolt with a stripped head, under which a transverse threaded hole is made in the side face of the nut. According to the embodiment, the nut includes a clamping part with a smooth, for example, conical, side surface and a twisted part with a multifaceted side surface, in which the specified hole is made (according to patent RU 142408, F16B 39/04, publ. 06/27/2014).

The disadvantage of this solution is the presence of an additional pin bolt for fixing the twisted part. In addition, the thread is made on the twisted part. This limits its rotation relative to the clamping part, which does not guarantee the separation of the twisted part when tightening the nut.

Known tear-off nut, which has a threaded part with an internal thread and a profiled nut head. The threaded part is in the form of a truncated cone with a smaller diameter end connected to the head of the nut, forming the ideal break point. The nut head has an inner hole, the diameter of which is smaller than the outer diameter of the threaded part and larger than the nominal diameter of the inner thread (according to the patent DE 10326005, F16B 41/00, publ. 30.12.2004).

The disadvantage of this nut is that the side surface of the clamping part is made conical, which does not provide reliable protection against twisting.

The closest technical solution is a non-loosening nut containing a head and a body. The body of the nut has a spherical shape. A threaded hole is drilled in the nut body. There is a hole on the head of the nut. The section of the connecting part between the body of the nut and the head of the nut has a thin-walled arc section, set in accordance with the magnitude of the torque. The hole in the head is larger than the threaded hole. The head of the nut is hexagonal (according to the patent CN 102155485, F16B 41/00, published on August 17, 2011).

The disadvantage of this nut is that the side surface of the clamping part is made conical, which does not provide reliable protection against twisting. Also a disadvantage is the arc section of the connecting part. The separation of the head in this place will not be uniform. The place of separation will have burrs, sharp edges.

The technical result, which the proposed utility model is aimed at, is to realize the purpose, as well as to provide protection against loosening of the nut due to the design.

This technical result is achieved by the fact that the anti-vandal tear-off nut consists of a clamping part and a twisted part with edges (for example, made in the form of a hexagon) connected by a neck, a through longitudinal hole is made in the nut, in which a thread is made on the side of the clamping part, the length of which is not exceeds the length of the clamping part, while the diameter of the hole on the side of the twisted part is greater than the diameter of the thread, and differs in that the outer surface of the clamping part consists of two surfaces of rotation, tapering from the end of the nut to the neck and located at an angle to each other, while the extreme surface has a convex arcuate shape.

In addition, the surface of revolution adjacent to the neck may have an arcuate convex shape.

In addition, the length of the surface of revolution adjacent to the neck may be from 0.5 to 2 times the length of the extreme surface of revolution.

The proposed utility model is illustrated by the following drawings, which show a particular case of its implementation:

Fig. 1 - tear-off anti-vandal nut, axonometric view;

Fig. 2 - tear-off anti-vandal nut, axonometric view;

Fig. 3 - tear-off anti-vandal nut, longitudinal section;

Fig. 4 - tightening the nut;

Fig. 5 - failure of the twisted part of the nut.

Anti-vandal detachable nut 1 (Fig. 1, 2) consists of a clamping part 2 and a twisted part 3, made in the form of a hexagon. The clamping part 2 and the twisted part 3 are connected by a neck 4. A through longitudinal hole 5 is made in the nut, in which a thread 6 is made from the side of the clamping part.

The outer surface of the clamping part 2 (Fig. 3) consists of two surfaces of rotation having a convex arcuate shape: the extreme surface of rotation 7 is located at the end of the nut, and the surface of rotation 8 is adjacent to the neck 4. The surfaces of rotation 7 and 8 narrow from the end of the nut to the neck and are located at an angle α to each other. The length L _{1 of} the surface of rotation 8 adjacent to the neck is from 0.5 to 2 lengths L _{2 of} the extreme surface of rotation 7.

The length L _{3 of} the thread 6 does not exceed the length L _{4 of} the clamping part 2, while the diameter D _{1 of} the hole 5 on the side of the twisted part 2 is greater than the diameter of the thread D ₂ .

Application.

Anti-vandal detachable nut is used for fastening together with screws, bolts, studs and other fasteners with external thread. To perform fastening, the nut 1 (Fig. 4) is screwed onto the fastener 9 until it stops. After that, it is necessary to apply force to break the twisted part 3. The breakage occurs along the neck 4 - the thinnest place of the nut. The thickness of the neck is calculated in such a way as to provide the necessary tightening force until the twisted part 3 is broken. After that, the twisted part 3 is removed from the fastener 9 (Fig. 5).

The execution of the outer surface of the twisted part of the nut in the form of two surfaces of revolution, so that the extreme surface has a convex arcuate shape, tapering from the end of the nut to the neck and located at an angle to each other, makes it difficult to unscrew the nut after tightening it, since it is impossible to reliably hook on the outer surface twisted part with some tool. When using gas-type keys for unscrewing, it will not be possible to achieve full contact with the surface of the clamping part, the formation of a hollow zone is inevitable. To turn out such a clamping part, you will need to use an individual nozzle that completely matches the shape (length and width) of both surfaces of rotation. The implementation of the surface of revolution adjacent to the neck, arcuate shape further complicate the process of unscrewing. To achieve maximum complication of engagement by any tool on the outer surfaces of the twisted part of the nut, the lengths of the surfaces are preferably performed in the ratio: the length of the surface of rotation adjacent to the neck should be from 0.5 to 2 lengths of the extreme surface of rotation.

Thus, the solutions presented in the utility model make it possible to implement a nut structure protected from unscrewing and thereby ensure the achievement of a technical result.

Claims (4)

1. Anti-vandal tear-off nut, consisting of a clamping part and a twisted part with faces connected by a neck, a through longitudinal hole is made in the nut, in which a thread is made on the side of the clamping part, the length of which does not exceed the length of the clamping part, while the diameter of the hole on the side of the twisted part is larger than the thread diameter, characterized in that the outer surface of the clamping part consists of two surfaces of rotation, tapering from the end of the nut to the neck and located at an angle to each other, while the outer surface has a convex arcuate shape. 2. Nut according to claim 1, characterized in that the surface of rotation adjacent to the neck has an arcuate convex shape. 3. Nut according to claim. 1 or 2, characterized in that the length of the surface of rotation adjacent to the neck is from 0.5 to 2 lengths of the extreme surface of rotation. 4. Nut according to claim 1 or 2, characterized in that the twisted part is made in the form of a hexagon.

Images