CN113357246B

CN113357246B - Bolt

Info

Publication number: CN113357246B
Application number: CN202110694464.7A
Authority: CN
Inventors: 贾忠军; 央青卓玛
Original assignee: Qinghai Zuoqiyou Electric Technology Service Co ltd
Current assignee: Qinghai Zuoqiyou Electric Technology Service Co ltd
Priority date: 2021-06-22
Filing date: 2021-06-22
Publication date: 2022-11-11
Anticipated expiration: 2041-06-22
Also published as: CN113357246A

Abstract

The application relates to a bolt which comprises a screw rod, a bolt head and a piston assembly, wherein the bolt head is connected to one end of the screw rod and is provided with a first through hole; the piston assembly is adapted to the first through hole and comprises a cylinder body and a piston, the cylinder body is provided with a piston cavity, the piston is movably connected in the piston cavity, a heat conducting medium is arranged between one end of the piston and the piston cavity, the heat conducting medium is configured to be capable of responding to the change of environmental parameters and the change of volume, and the environmental parameters comprise temperature. Like this, when electrical connection department makes the contact resistance increase because of the bolt is not hard up, and then when making the contact surface generate heat, because the heat-conduction effect, the piston intracavity heat-conducting medium volume increase promotes the piston and moves towards the cylinder body is external to make pressure increase between cable connection nose and the outlet plate, contact resistance reduces, and electrical connection department temperature reduces, reaches the purpose of independently cooling.

Description

Bolt

Technical Field

The application relates to the technical field of electric power, in particular to a bolt.

Background

At present, bolts are widely applied in the power industry, and a large number of bolts are needed among running transmission, transformation and distribution system equipment and facilities so as to realize distribution and transmission of electric energy. Under the condition of long-term operation, the fatigue of the bolt is loosened, and the contact surface of the electrical connecting piece is easily heated and even fused in a current-carrying state. Especially, when the cable terminal adopts a single-aperture connection lug and is connected with an outlet plate through a bolt, the problems are easy to cause accidents such as power supply interruption and the like. In the prior art, in order to prevent the joint of the bolt and the nut from loosening, a stop member such as a stop washer is generally used to prevent the relative rotation between the thread and the component.

However, the problem that the electrical connection is easy to generate heat in a current-carrying state cannot be fundamentally solved by the existing bolt for preventing looseness.

Disclosure of Invention

Therefore, it is necessary to provide a bolt capable of solving the problem of heat generation at the electrical connection portion, in order to solve the problem of heat generation at the electrical connection portion.

According to an aspect of the present application, there is provided a bolt including:

a screw;

the bolt head is connected to one end of the screw rod, a first through hole is formed in one side, close to the screw rod, of the bolt head, and the axis of the first through hole is parallel to the axis of the screw rod;

the bolt further includes a piston assembly adapted within the first through bore, the piston assembly including: a cylinder mounted in the first through-hole, the cylinder having a piston cavity;

the piston is movably connected in the piston cavity, and a heat conducting medium is arranged between one end of the piston and the piston cavity;

wherein the thermally conductive medium is configured to change in volume in response to a change in an environmental parameter; the environmental parameter includes temperature.

Above-mentioned bolt, through the piston assembly who has the thermal conductivity medium in the bolt head sets up, when electrical connection department makes contact resistance increase because of bolt looseness, and then when making the contact surface generate heat, because the heat-conduction effect, the increase of thermal conductivity medium volume in the piston chamber promotes the piston and removes towards the cylinder body is external, thereby make pressure increase between cable wiring nose and the outlet plate, this pressure size is directly proportional with the temperature, contact resistance reduces along with this pressure increase, make electrical connection department temperature reduction, thereby reach the purpose of independently cooling.

In one embodiment, the heat conducting medium is configured to increase in volume as the temperature of the environment increases, so as to push the piston outwards.

In one embodiment, the cylinder body comprises a piston cavity and a blocking cavity, wherein the piston cavity is communicated with the blocking cavity, and one end of the blocking cavity is communicated with the piston cavity;

the piston assembly further includes:

the plugging piece is arranged at the joint of the piston cavity and the plugging cavity;

and the plugging head is in threaded connection with the other end of the plugging cavity and is constructed to be pressed against the plugging sheet so that the plugging sheet can seal one end of the piston cavity, which is far away from the piston.

In one embodiment, a stepped hole is formed in one end, close to the piston, of the blocking head;

the plugging sheet is adapted to the stepped hole.

In one embodiment, the stepped bore includes a first stepped bore and a second stepped bore communicating with each other;

the radial size of the first stepped hole is smaller than that of the second stepped hole, the plugging piece is installed in the second stepped hole, and the radial size of the second stepped hole is larger than that of the piston cavity.

In one embodiment, the piston assembly further comprises a first seal ring;

the first sealing ring is arranged on the blocking head so that liquid sealing is formed between the blocking head and the blocking cavity.

In one embodiment, the piston comprises:

a piston body movably and sealingly connected to the piston cavity; and

the pressing part is connected to one end of the piston body, which is far away from the heat conducting medium;

the radial dimension of the pressing part is larger than that of the piston cavity.

In one embodiment, the piston assembly further comprises a second sealing ring and a third sealing ring which are arranged at intervals along the axial direction of the piston cavity;

the second sealing ring and the third sealing ring are arranged on the piston, and liquid sealing is formed between the second sealing ring and the third sealing ring and the piston cavity.

In one embodiment, the first through holes include a plurality of first through holes, and the first through holes are arranged in a central symmetry manner with the axis of the bolt as a reference.

In one embodiment, the bolt head is configured in a plum blossom shape, and the axis of the screw is coincident with the axis of the bolt head;

the plurality of first through holes are respectively positioned in the centers of the petals of the bolt heads in a plum blossom shape.

Drawings

FIG. 1 is a schematic structural diagram of a bolt according to an embodiment of the present application;

FIG. 2 is a cross-sectional view of a piston assembly according to an embodiment of the present application;

FIG. 3 is a schematic view of a piston according to an embodiment of the present application;

FIG. 4 is a cross-sectional view of a cylinder according to an embodiment of the present application;

FIG. 5 is a cross-sectional view of a stopper head according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a bolt head according to an embodiment of the present application.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiments in many different forms than those described herein and that modifications may be made by one skilled in the art without departing from the spirit and scope of the application and it is therefore not intended to be limited to the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and encompass, for example, both fixed and removable connections or integral parts thereof; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. As used herein, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are for purposes of illustration only and do not denote a single embodiment.

At present, bolts are widely applied to the power industry, particularly under the condition that a single-aperture wiring lug is generally adopted at a cable terminal, the wiring lug needs to be connected with an outlet plate through a bolt fastener, and after long-term operation, the electrical connection part is easy to generate heat and even fuse, so that accidents such as power supply interruption or fire disasters are caused. The main reason for the above problem is that when the electrical equipment is in operation, the joints of the electrical equipment are loosened by mechanical shock or fatigue of the bolts themselves, so that the pressure on the contact surfaces of the joints is reduced, the contact area is reduced, the contact resistance is increased, and the joints generate heat. On the other hand, when the metal at the connection portion expands due to overheating, a gap is formed between the contact surfaces, oxidation of the contact surfaces is accelerated, contact resistance rapidly increases due to film resistance generated by the oxide film, heat generation is increased, and a vicious cycle is formed. In the prior art, the locking washer is mostly arranged to prevent looseness, but the mode cannot fundamentally solve the problem of heat generation at the electric connection part.

Therefore, it is necessary to provide a bolt that can solve the problem of heat generation at the electrical connection.

FIG. 1 is a schematic structural diagram of a bolt according to an embodiment of the present application; FIG. 2 is a cross-sectional view of a piston assembly according to an embodiment of the present application.

Referring to fig. 1 and 2, a bolt according to an embodiment of the present invention includes a threaded shaft 10, a bolt head 20, and a piston assembly 30. The bolt head 20 is connected to one end of the screw 10, a first through hole 22 is formed in one side, close to the screw 10, of the bolt head 20, the axis of the first through hole 22 is parallel to the axis of the screw 10, and the piston assembly 30 is matched with the first through hole 22.

As shown in fig. 2, the piston assembly 30 includes a cylinder 32 and a piston 34. The cylinder 32 is installed in the first through hole 22, the cylinder 32 has a piston cavity 322, the piston 34 is movably connected in the piston cavity 322, and a heat conducting medium is disposed between one end of the piston 34 and the piston cavity 322, wherein the heat conducting medium is configured to change in volume in response to a change in an environmental parameter, the environmental parameter including temperature. In particular embodiments, the thermally conductive medium is configured to increase in volume as the temperature of the environment in which it is located increases to urge the piston 34 outward.

Like this, lead to electrical connection department contact resistance increase when the bolt is not hard up to when making the junction generate heat, because the heat-conduction effect, the volume increase that is heated of the heat-conducting medium in the piston chamber 322 promotes piston 34 and outwards moves, makes pressure increase between cable connection nose and the outlet plate, and contact resistance diminishes, and electrical connection department temperature reduces, reaches the effect of independently cooling.

In some embodiments, as shown in fig. 1, the first through hole 22 includes a first portion 222 and a second portion 224, the first portion 222 is disposed on one side of the bolt head 20 near the bolt 10 and is adapted to fit the piston assembly 30, the second portion 224 is disposed on the other side of the bolt head 20, and the radial dimension of the second portion 224 is smaller than that of the first portion 222. The piston assembly 30 is easily assembled and disassembled and moved by providing the second portion 224 with a smaller radial dimension.

Specifically, as shown in fig. 2, the piston assembly 30 further includes a second sealing ring 37 and a third sealing ring 38 arranged at intervals along the axial direction of the piston cavity 322, and the second sealing ring 37 and the third sealing ring 38 are disposed on the piston 34 and form a liquid seal with the piston cavity 322. The second sealing ring 37 and the third sealing ring 38 are arranged on the piston 34, so that the heat conducting medium in the piston cavity 322 is prevented from leaking and losing the function.

Fig. 3 is a schematic structural diagram of a piston according to an embodiment of the present application.

As shown in fig. 3, in some embodiments, the piston 34 includes a piston body 342 and a pressing portion 344. As shown in fig. 2, the piston body 342 is movably and hermetically connected to the piston cavity 322, the pressing portion 344 is connected to an end of the piston body 342 away from the heat conducting medium, and a radial dimension of the pressing portion 344 is larger than a radial dimension of the piston cavity 322. Preferably, the radial dimension of the pressing portion 344 is equal to the outer radial dimension of the cylinder 32. By providing the pressing portion 344, when the volume of the heat conducting medium in the piston cavity 322 decreases as the bolt cools, the piston 34 is prevented from retracting into the cylinder 32 and the pressure on the contact surface is reduced.

FIG. 4 is a cross-sectional view of a cylinder in an embodiment of the present application.

Referring to fig. 2 and 4, in some embodiments of the present application, the cylinder 32 further includes a blocking cavity 324, and the piston assembly 30 further includes a blocking piece 35 and a blocking head 36. As shown in fig. 4, one end of the blocking chamber 324 communicates with the piston chamber 322. As shown in fig. 2, the plugging sheet 35 is arranged at the connection part of the piston cavity 322 and the plugging cavity 324; the blocking head 36 is screwed to the other end of the blocking cavity 324 and is configured to press against the blocking sheet 35, so that the blocking sheet 35 can seal the end of the piston cavity 322 far away from the piston 34. By providing the blocking cavity 324, redundant amounts of the heat conducting medium in the piston cavity 322 can be accommodated by the blocking cavity 324. By arranging the plugging sheet 35, and the plugging sheet 35 and the piston 34 can respectively seal two ends of the piston cavity 322, after the overall temperature of the bolt is reduced, the movement amount of the piston 34 cannot return due to volume contraction caused by temperature reduction of the heat conducting medium, so that the joint is heated again, and the plugging sheet 35 has a one-way check effect on the piston 34.

In an embodiment, as shown in fig. 2, the piston assembly 30 further includes a first sealing ring 39, and the first sealing ring 39 is disposed on the blocking head 36, so that a liquid seal is formed between the blocking head 36 and the blocking cavity 324, and the heat conducting medium is prevented from leaking from one end of the blocking head 36.

Fig. 5 is a cross-sectional view of the stopper head 36 according to an embodiment of the present application.

As shown in fig. 2 and 5, the end of the plugging head 36 close to the piston 34 is provided with a stepped hole 362, and the plugging piece 35 is fitted into the stepped hole 362. Specifically to the embodiment, stepped bore 362 includes a first stepped bore 3624 and a second stepped bore 3622 that communicate with each other; the radial dimension of the first stepped hole 3624 is smaller than the radial dimension of the second stepped hole 3622, the plugging piece 35 is installed in the second stepped hole 3622, and the radial dimension of the second stepped hole 3622 is larger than the radial dimension of the piston cavity 322. By arranging the first stepped hole 3624 of which the radial dimension is smaller than that of the second stepped hole 3622, the plugging chamber 324 can be pressed against the plugging sheet 35, so that when the plugging sheet 35 is subjected to pressure from a heat conducting medium in the piston chamber 322, the plugging sheet 35 is tightly attached to a stepped surface between the second stepped hole 3622 and the first stepped hole 3624, and sealing of one end, close to the plugging chamber 324, of the piston chamber 322 is realized. The radial size of the second stepped hole 3622 is larger than that of the piston cavity 322, so that the piston 34 is actually limited in the second stepped hole 3622, and the blocking piece 35 is prevented from being removed into the piston cavity 322 and losing a non-return effect.

Referring to fig. 6, in some embodiments of the present disclosure, the first through hole 22 includes a plurality of first through holes 22, and the plurality of first through holes 22 are arranged in a central symmetry with respect to an axis of the bolt. Through the arrangement of the through holes, when the electric connection part generates heat, the thrust of the pistons 34 jointly acts on the contact surface of the electric connection part, the contact pressure is further increased, the contact area is increased, and the contact resistance is reduced.

In some embodiments, as shown in fig. 1, the axis of the screw shaft 10 coincides with the axis of the bolt head 20, and as shown in fig. 6, the bolt head 20 is configured in a quincunx shape, and the plurality of first through holes 22 are respectively located at the centers of the petals of the quincunx bolt head 20. In the preferred embodiment, the bolt head 20 having a quincunx shape is configured to include three petals, effectively enhancing contact pressure, and has an advantage of simple structure.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A bolt, comprising:

a screw;

the bolt further includes a piston assembly adapted within the first through bore, the piston assembly including:

a cylinder mounted in the first through-hole, the cylinder having a piston cavity;

wherein the thermally conductive medium is configured to change in volume in response to a change in an environmental parameter; the environmental parameter is temperature.

2. The stud according to claim 1 wherein the thermally conductive medium is configured to increase in volume as the temperature of its environment increases to urge the piston outward.

3. The bolt according to claim 1, wherein the cylinder includes a piston chamber and a block chamber having one end communicating with the piston chamber, which communicate with each other;

the piston assembly further includes:

4. The bolt according to claim 3, wherein a stepped hole is formed at one end of the blocking head close to the piston;

the plugging sheet is adapted to the stepped hole.

5. The bolt according to claim 4, wherein the stepped bore includes a first stepped bore and a second stepped bore in communication with each other;

6. The bolt according to claim 3, wherein the piston assembly further comprises a first seal ring;

the first sealing ring is arranged on the plugging head so that liquid sealing is formed between the plugging head and the plugging cavity.

7. The bolt according to claim 1, wherein the piston comprises:

a piston body movably and sealingly connected to the piston cavity; and

8. The bolt according to claim 7, wherein the piston assembly further comprises a second seal ring and a third seal ring arranged at intervals along the axial direction of the piston cavity;

the second sealing ring and the third sealing ring are arranged on the piston, and liquid sealing is formed between the second sealing ring and the piston cavity.

9. The bolt according to claim 1, wherein the first through hole comprises a plurality of first through holes arranged in a central symmetry with respect to an axis of the bolt.

10. The bolt according to claim 9, wherein the bolt head is configured in a quincuncial shape, an axis of the shank coinciding with an axis of the bolt head;

the first through holes are respectively positioned in the petal centers of the bolt heads in the plum blossom shape.