阅读说明：本技术 一种汽车使用的紧固螺栓及其制备方法 (Fastening bolt for automobile and preparation method thereof ) 是由 燕频 于 2020-12-16 设计创作，主要内容包括：本发明涉及一种汽车使用的紧固螺栓,包括金属螺杆、第一螺母和第二螺母；金属螺杆的一端设有长距螺纹槽,另一端设有短距螺纹槽；金属螺杆的两端均向内凹陷设有六角内槽；第一螺母上设有与长距螺纹槽相匹配的第一螺纹通孔；第二螺母的一端设有与第一限位环相匹配的第二限位环,所述第二螺母的另一端设有与短距螺纹槽相匹配的第二螺纹通孔；金属螺杆、第一螺母和第二螺母的组分按质量百分比,C0.35％～0.40％、Mn0.40％～0.60％、Si0.10％～0.30％、S≤0.003％、P≤0.010％、Cr4.75％～5.50％、Mo1.75％～1.95％、V0.40％～0.65％、Ni≤0.20％、Cu≤0.20％,其余为Fe。本发明还涉及一种汽车使用的紧固螺栓的制备方法。本发明的一种汽车使用的紧固螺栓,适用于汽车领域,安装方便,且紧固效果良好。(The invention relates to a fastening bolt for an automobile, which comprises a metal screw, a first nut and a second nut; one end of the metal screw is provided with a long-distance thread groove, and the other end of the metal screw is provided with a short-distance thread groove; both ends of the metal screw rod are inwards sunken to be provided with hexagonal inner grooves; the first nut is provided with a first threaded through hole matched with the long-distance thread groove; one end of the second nut is provided with a second limiting ring matched with the first limiting ring, and the other end of the second nut is provided with a second threaded through hole matched with the short-distance thread groove; the metal screw, the first nut and the second nut comprise, by mass, 0.35-0.40% of C, 0.40-0.60% of Mn0.10-0.30% of Si, less than or equal to 0.003% of S, less than or equal to 0.010% of P, 4.75-5.50% of Cr4.75-1.95% of Mo1.40%, 0.40-0.65% of V, less than or equal to 0.20% of Ni, less than or equal to 0.20% of Cu, and the balance of Fe. The invention also relates to a preparation method of the fastening bolt for the automobile. The fastening bolt for the automobile is suitable for the field of automobiles, is convenient to install and has a good fastening effect.)

1. A fastening bolt for an automobile is characterized by comprising a metal screw, a first nut and a second nut;

one end of the metal screw is provided with a long-distance thread groove, and the other end of the metal screw is provided with a short-distance thread groove; the end part of the short-distance thread groove is provided with a first limiting ring, and the first limiting ring and the metal screw are of an integrally formed structure; both ends of the metal screw rod are provided with hexagonal inner grooves in an inwards concave manner;

the first nut is provided with a first threaded through hole matched with the long-distance threaded groove, and the first nut is connected to the part, provided with the long-distance threaded groove, of the metal screw rod through the first threaded through hole;

one end of the second nut is provided with a second limiting ring matched with the first limiting ring, the other end of the second nut is provided with a second threaded through hole matched with the short-distance thread groove, and the second threaded through hole penetrates through the second limiting ring all the time; the second nut is sleeved at the part of the metal screw rod, which is provided with the short-distance thread groove, through the second thread through hole, and the second limiting ring is opposite to the first limiting ring;

the metal screw, the first nut and the second nut comprise, by mass, 0.35-0.40% of C, 0.40-0.60% of Mn0.10-0.30% of Si, less than or equal to 0.003% of S, less than or equal to 0.010% of P, 4.75-5.50% of Cr4.75-1.95% of Mo1.40%, 0.40-0.65% of V, less than or equal to 0.20% of Ni, less than or equal to 0.20% of Cu, and the balance Fe.

2. The fastening bolt for automobile as claimed in claim 1, wherein the first nut has a plurality of first ribs on an outer surface thereof.

3. The fastening bolt for automobile as claimed in claim 1, wherein the second nut has a plurality of second ribs on its outer surface.

4. A fastening bolt for automobile according to any one of claims 1 to 3, wherein a rubber layer is provided on each of the opposing surfaces of the first and second stop rings.

5. A fastening bolt for vehicle according to any one of claims 1 to 3, wherein the direction of rotation of the long pitch thread groove is opposite to that of the short pitch thread groove.

6. The fastening bolt for the automobile according to any one of claims 1 to 3, wherein the surfaces of the metal screw, the first nut and the second nut are coated with a layer of antirust paint.

7. A method for preparing a fastening bolt for an automobile is characterized by mainly comprising the following steps,

step one, processing a metal screw: the casting process comprises the following steps: smelting raw materials by an electric arc furnace or an induction furnace, adopting vacuum full mold casting, precision casting or sand mold casting technology, wherein the mold temperature is 250 ℃ during casting, the casting temperature of the vanadium wear-resistant alloy cast iron is 1450 ℃, slowly cooling the cast to be lower than 100 ℃ after casting, and demolding; the heat treatment process comprises the following steps: annealing the raw material extrusion screw in a protective atmosphere furnace, keeping the annealing temperature at 920 ℃ for 4 hours, cooling the furnace to 660 ℃, keeping the temperature for 7 hours, cooling the furnace to 200 ℃, and discharging. Heating the quenching product in a protective atmosphere furnace to 950 ℃, preserving heat for 3 hours, taking out the quenching product from the furnace, cooling the quenching product for 3 minutes to quench oil, and taking out the quenching product from the oil to room temperature after the quenching product is cooled to about 300 ℃. Heating to 520 ℃ during tempering; preserving the heat for 3 hours, cooling the furnace to 400 ℃, discharging the furnace and air cooling;

step two, processing the first nut and the second nut: selecting materials; forging to obtain a round bar-shaped steel material; heat treatment, wherein the specific process sequentially comprises annealing, normalizing, primary quenching, medium-temperature tempering, carburizing, secondary quenching and low-temperature tempering; milling an end face; drilling a central hole; milling a spiral groove, placing the processed steel in a thread rolling die, positioning by using a positioning tool, and performing thread rolling operation; and milling chamfers at two ends to obtain a finished product.

Technical Field

The invention relates to the field of automobile part equipment, in particular to a fastening bolt for an automobile and a preparation method thereof.

Background

Bolt: mechanical parts, cylindrical threaded fasteners fitted with nuts. A fastener consisting of a head part and a screw (a cylinder with external threads) needs to be matched with a nut and is used for fastening and connecting two parts with through holes. This form of connection is known as a bolted connection. If the nut is unscrewed from the bolt, the two parts can be separated, so that the bolt connection belongs to detachable connection.

Chinese patent application publication No. CN111946708A discloses a fastening bolt capable of being quickly disassembled and assembled. The technical scheme is as follows: the utility model provides a but quick assembly disassembly's fastening bolt, includes the metal screw, the below of metal screw is provided with hexagon nut, and hexagon nut's inboard is provided with the nut screw hole, the top of metal screw is provided with hexagon nut, hexagon nut's bottom is provided with the pretension gasket, and pretension gasket and hexagon nut welded connection, the metal screw is including the non-resistance body of rod, the one end of the non-resistance body of rod is provided with long-distance thread groove, and the other end is provided with short-distance thread groove. However, the above-mentioned device cannot precisely turn over the liquid crystal panel in the production process so as to be accurately placed on the inspection equipment for precise inspection. The bolt solves the problem that the bolt in the prior art can be independently used as a connecting piece in the using process and can also be matched with a nut to be fixed. However, the nut and the metal screw at the end portion are relatively connected with each other insecurely and are easy to loosen, so that the application range is relatively limited.

Therefore, it is desirable to provide a fastening bolt for an automobile and a method for manufacturing the same, which can solve the above-mentioned technical problems.

Disclosure of Invention

The invention aims to provide a fastening bolt for an automobile, which is suitable for the field of automobiles, convenient to install and good in fastening effect.

In order to achieve the purpose of the invention, the fastening bolt for the automobile comprises a metal screw rod, a first nut and a second nut;

one end of the metal screw is provided with a long-distance thread groove, and the other end of the metal screw is provided with a short-distance thread groove; the end part of the short-distance thread groove is provided with a first limiting ring, and the first limiting ring and the metal screw are of an integrally formed structure; both ends of the metal screw rod are provided with hexagonal inner grooves in an inwards concave manner;

the first nut is provided with a first threaded through hole matched with the long-distance threaded groove, and the first nut is connected to the part, provided with the long-distance threaded groove, of the metal screw rod through the first threaded through hole; as shown in fig. 4, one end of the second nut is provided with a second limit ring matched with the first limit ring, the other end of the second nut is provided with a second threaded through hole matched with the short-distance thread groove, and the second threaded through hole penetrates through the second limit ring; the second nut is sleeved at the part of the metal screw rod, which is provided with the short-distance thread groove, through the second thread through hole, and the second limiting ring is opposite to the first limiting ring;

the metal screw, the first nut and the second nut comprise, by mass, 0.35-0.40% of C, 0.40-0.60% of Mn0.10-0.30% of Si, less than or equal to 0.003% of S, less than or equal to 0.010% of P, 4.75-5.50% of Cr4.75-1.95% of Mo1.40%, 0.40-0.65% of V, less than or equal to 0.20% of Ni, less than or equal to 0.20% of Cu, and the balance Fe.

Preferably, a plurality of first protruding strips are arranged on the outer surface of the first nut.

Preferably, a plurality of second convex strips are arranged on the outer surface of the second nut.

Preferably, the opposite surfaces of the first limit ring and the second limit ring are provided with a rubber layer.

Preferably, the rotation directions of the long-distance thread groove and the short-distance thread groove are opposite.

Preferably, the surfaces of the metal screw, the first nut and the second nut are coated with a layer of antirust paint.

Another object of the present invention is to provide a method for manufacturing a fastening bolt for an automobile, which comprises the steps of,

step one, processing a metal screw: the casting process comprises the following steps: smelting raw materials by an electric arc furnace or an induction furnace, adopting vacuum full mold casting, precision casting or sand mold casting technology, wherein the mold temperature is 250 ℃ during casting, the casting temperature of the vanadium wear-resistant alloy cast iron is 1450 ℃, slowly cooling the cast to be lower than 100 ℃ after casting, and demolding; the heat treatment process comprises the following steps: annealing the raw material extrusion screw in a protective atmosphere furnace, keeping the annealing temperature at 920 ℃ for 4 hours, cooling the furnace to 660 ℃, keeping the temperature for 7 hours, cooling the furnace to 200 ℃, and discharging. Heating the quenching product in a protective atmosphere furnace to 950 ℃, preserving heat for 3 hours, taking out the quenching product from the furnace, cooling the quenching product for 3 minutes to quench oil, and taking out the quenching product from the oil to room temperature after the quenching product is cooled to about 300 ℃. Heating to 520 ℃ during tempering; preserving the heat for 3 hours, cooling the furnace to 400 ℃, discharging the furnace and air cooling;

step two, processing the first nut and the second nut: selecting materials; forging to obtain a round bar-shaped steel material; heat treatment, wherein the specific process sequentially comprises annealing, normalizing, primary quenching, medium-temperature tempering, carburizing, secondary quenching and low-temperature tempering; milling an end face; drilling a central hole; milling a spiral groove, placing the processed steel in a thread rolling die, positioning by using a positioning tool, and performing thread rolling operation; and milling chamfers at two ends to obtain a finished product.

Compared with the prior art, the fastening bolt for the automobile has the following advantages that:

(1) the fastening bolt is divided into the metal screw, the first nut and the second nut, so that the single application and the integral use are facilitated, the long-distance thread groove and the short-distance thread groove are respectively arranged at the two ends of the metal screw, the rotating directions of the long-distance thread groove and the short-distance thread groove are opposite, and the first nut and the second nut cannot be influenced during installation and disassembly;

(2) the first limiting ring is arranged, so that the metal screw can be quickly positioned, the mounting speed is accelerated, meanwhile, the second limiting ring is arranged on the second nut, the contact area between the second nut and the mounting surface is increased, the resistance between the second nut and the mounting surface is improved, and the looseness is effectively prevented;

(3) simple structure and convenient and fast use.

Drawings

FIG. 1 is a schematic structural diagram 1 of a metal screw in this example 1;

fig. 2 is a schematic structural diagram 2 of a metal stud in this embodiment 1;

fig. 3 is a schematic structural diagram of a first nut in the embodiment 1;

fig. 4 is a schematic structural diagram of a second nut in the embodiment 1;

fig. 5 is an exploded view of a fastening bolt for use in an automobile according to embodiment 1;

fig. 6 is a schematic structural view of a fastening bolt used in an automobile according to embodiment 1.

Detailed Description

The invention is further described below with reference to the following figures and specific examples.

Example 1

As shown in fig. 1 to 6, a fastening bolt for an automobile includes a metal screw 4, a first nut 6, and a second nut 9;

as shown in fig. 1-2, one end of the metal screw 4 is provided with a long-distance thread groove 5, and the other end is provided with a short-distance thread groove 1; a first limiting ring 3 is arranged at the end part of the short-distance thread groove 1, and the first limiting ring 3 and the metal screw 4 are of an integrally formed structure; both ends of the metal screw rod 4 are provided with hexagonal inner grooves 2 in an inwards concave manner; the disassembly is convenient;

as shown in fig. 3, a first threaded through hole 7 matched with the long-distance threaded groove 5 is formed in the first nut 6, and the first nut 6 is connected to the position, on which the long-distance threaded groove 5 is formed, of the metal screw 4 through the first threaded through hole 7; preferably, in order to facilitate an operator to hold the first nut 6, a plurality of first protruding strips 8 are arranged on the outer surface of the first nut 6, so that the surface roughness of the first nut is increased, and the first nut 6 is prevented from falling off when the operator is installed;

as shown in fig. 4, one end of the second nut 9 is provided with a second limit ring 12 matched with the first limit ring 3, the other end of the second nut 9 is provided with a second threaded through hole 10 matched with the short-distance thread groove 1, and the second threaded through hole 10 penetrates through the second limit ring 12 all the time; the second nut 9 is sleeved on the part of the metal screw 4 provided with the short-distance thread groove 1 through a second thread through hole 10, and the second limiting ring 12 is opposite to the first limiting ring 3; by the arrangement, the contact area between the second nut 9 and the mounting surface can be increased, and the first limiting ring 3 can play a role in positioning and accelerate the mounting speed; preferably, a plurality of second convex strips 11 are arranged on the outer surface of the second nut 9, and the function of the second convex strips is the same as that of the first convex strips 8.

In this embodiment, a rubber layer is disposed on the surface of the first stop collar 3 opposite to the second stop collar 12 to increase the friction force and prevent the sliding during installation.

In the present embodiment, the long pitch thread groove 5 and the short pitch thread groove 1 have opposite rotation directions, so that when the first nut 6 or the second nut 9 is rotated, no mutual influence is caused, and loosening is caused.

In addition, the surfaces of the metal screw 4, the first nut 6 and the second nut 9 are coated with a layer of antirust paint, so that the service life of the nut is prolonged.

Wherein the composition of the metal screw, the first nut and the second nut is as shown in table 1.

TABLE 1

As shown in fig. 5 to 6, when the automobile is installed, the metal screw rod 4 firstly penetrates through a corresponding screw hole on the automobile, the first limiting ring 3 plays a limiting role, and the part of the metal screw rod 4, on which the long-distance thread groove 5 is arranged, is fixed through the first nut 6 at the upper part; then, the second nut 9 is sleeved on the part of the metal screw 4, on which the short-distance thread groove 1 is arranged, and then the second nut is fixed.

The preparation method comprises the following steps:

step one, processing a metal screw: the casting process comprises the following steps: smelting raw materials by an electric arc furnace or an induction furnace, adopting vacuum full mold casting, precision casting or sand mold casting technology, wherein the mold temperature is 250 ℃ during casting, the casting temperature of the vanadium wear-resistant alloy cast iron is 1450 ℃, slowly cooling the cast to be lower than 100 ℃ after casting, and demolding; the heat treatment process comprises the following steps: annealing the raw material extrusion screw in a protective atmosphere furnace, keeping the annealing temperature at 920 ℃ for 4 hours, cooling the furnace to 660 ℃, keeping the temperature for 7 hours, cooling the furnace to 200 ℃, and discharging. Heating the quenching product in a protective atmosphere furnace to 950 ℃, preserving heat for 3 hours, taking out the quenching product from the furnace, cooling the quenching product for 3 minutes to quench oil, and taking out the quenching product from the oil to room temperature after the quenching product is cooled to about 300 ℃. Heating to 520 ℃ during tempering; preserving the heat for 3 hours, cooling the furnace to 400 ℃, discharging the furnace and air cooling;

step two, processing the first nut and the second nut: selecting materials; forging to obtain a round bar-shaped steel material; heat treatment, wherein the specific process sequentially comprises annealing, normalizing, primary quenching, medium-temperature tempering, carburizing, secondary quenching and low-temperature tempering; milling an end face; drilling a central hole; milling a spiral groove, placing the processed steel in a thread rolling die, positioning by using a positioning tool, and performing thread rolling operation; and milling chamfers at two ends to obtain a finished product.

Example 2

The composition of the metal screw, the first nut, and the second nut in example 2 is shown in table 2, and other features are the same as in example 1.

TABLE 2

The preparation method comprises the following steps:

step one, processing a metal screw: the casting process comprises the following steps: smelting raw materials by an electric arc furnace or an induction furnace, adopting vacuum full mold casting, precision casting or sand mold casting technology, wherein the mold temperature is 250 ℃ during casting, the casting temperature of the vanadium wear-resistant alloy cast iron is 1450 ℃, slowly cooling the cast to be lower than 100 ℃ after casting, and demolding; the heat treatment process comprises the following steps: annealing the raw material extrusion screw in a protective atmosphere furnace, keeping the annealing temperature at 920 ℃ for 4 hours, cooling the furnace to 660 ℃, keeping the temperature for 7 hours, cooling the furnace to 200 ℃, and discharging. Heating the quenching product in a protective atmosphere furnace to 950 ℃, preserving heat for 3 hours, taking out the quenching product from the furnace, cooling the quenching product for 3 minutes to quench oil, and taking out the quenching product from the oil to room temperature after the quenching product is cooled to about 300 ℃. Heating to 520 ℃ during tempering; preserving the heat for 3 hours, cooling the furnace to 400 ℃, discharging the furnace and air cooling;

step two, processing the first nut and the second nut: selecting materials; forging to obtain a round bar-shaped steel material; heat treatment, wherein the specific process sequentially comprises annealing, normalizing, primary quenching, medium-temperature tempering, carburizing, secondary quenching and low-temperature tempering; milling an end face; drilling a central hole; milling a spiral groove, placing the processed steel in a thread rolling die, positioning by using a positioning tool, and performing thread rolling operation; and milling chamfers at two ends to obtain a finished product.

Example 3

The composition of the metal screw, the first nut, and the second nut in example 3 is shown in table 3, and other features are the same as in example 1.

TABLE 3

The preparation method comprises the following steps:

step one, processing a metal screw: the casting process comprises the following steps: smelting raw materials by an electric arc furnace or an induction furnace, adopting vacuum full mold casting, precision casting or sand mold casting technology, wherein the mold temperature is 250 ℃ during casting, the casting temperature of the vanadium wear-resistant alloy cast iron is 1450 ℃, slowly cooling the cast to be lower than 100 ℃ after casting, and demolding; the heat treatment process comprises the following steps: annealing the raw material extrusion screw in a protective atmosphere furnace, keeping the annealing temperature at 920 ℃ for 4 hours, cooling the furnace to 660 ℃, keeping the temperature for 7 hours, cooling the furnace to 200 ℃, and discharging. Heating the quenching product in a protective atmosphere furnace to 950 ℃, preserving heat for 3 hours, taking out the quenching product from the furnace, cooling the quenching product for 3 minutes to quench oil, and taking out the quenching product from the oil to room temperature after the quenching product is cooled to about 300 ℃. Heating to 520 ℃ during tempering; preserving the heat for 3 hours, cooling the furnace to 400 ℃, discharging the furnace and air cooling;

step two, processing the first nut and the second nut: selecting materials; forging to obtain a round bar-shaped steel material; heat treatment, wherein the specific process sequentially comprises annealing, normalizing, primary quenching, medium-temperature tempering, carburizing, secondary quenching and low-temperature tempering; milling an end face; drilling a central hole; milling a spiral groove, placing the processed steel in a thread rolling die, positioning by using a positioning tool, and performing thread rolling operation; and milling chamfers at two ends to obtain a finished product.

In order to verify the mechanical properties of the fastening bolt according to the present invention, the inventors sampled 5 pieces of the die steel obtained in examples 1 to 3, and performed the property test, and the test data is shown in table 3:

TABLE 3

Therefore, the fastening bolt provided by the invention has good mechanical property and provides powerful guarantee for the fastening effect.

While the preferred embodiments of the present invention have been described in detail, it will be understood by those skilled in the art that the invention is not limited thereto, and that various changes and modifications may be made without departing from the spirit of the invention, and the scope of the invention is defined in the appended claims.