Method for fastening flare nuts

Abstract

This invention provides a method for fastening flare nuts that does not require a large workspace and can be fastened in a short amount of time. [Solution] A method for fastening a flare nut 1 to a flare bolt 2 in order to fix a flare pipe 3 between a flare bolt 2 and a flare nut 1, comprising: a first step of temporarily fastening the flare nut 1 to the flare bolt 2 with the flare pipe 3 inserted into the flare nut 1; a second step of rotatably supporting a socket 6 connected to the tip of a rotating shaft 51 on a socket rotating shaft 41, and engaging the gear teeth 61 on the outer circumference of the socket 6 with the gear teeth 11 on the outer circumference of the flare nut 1; and a third step of rotating the socket 6 with a fastening tool 5 to fasten the flare nut 1 to the flare bolt 2, thereby fixing the flare pipe 3 with the flared portion 31 sandwiched between the tapered surface 21 and the inclined surface 13.

Description

Technical Field

[0001] The present invention relates to a method for fastening a flare nut. '

Background Art

[0002] Patent Document 1 discloses a flare nut screwing tool used for screwing a flare nut.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For pipes of brake oil in a hydraulic brake, fuel pipes in an LPG vehicle using LPG (Liquefied Petroleum Gas) as fuel, and pipes through which refrigerant of an air conditioner such as a car air conditioner flows, as a joint with high sealing performance reliability, a flare joint that connects a flare pipe with its end widened into a conical shape to a flare bolt with a flare nut is used. In such a flare joint, since it is essential to rotate the flare nut with an open-end wrench during fastening, a large space for rotating the open-end wrench is required, and the working time may become long by repeating the operation of fitting the open-end wrench to the flare nut, rotating it, and removing it.

[0005] )]] Therefore, an object of the present invention is to provide a method for fastening a flare nut that does not require a large working space and can be fastened in a short time.

Means for Solving the Problems

[0006] The flare nut fastening method according to the present invention is a method of fastening a flare nut to a flare bolt in order to fix a flare pipe, which has a flare portion at its tip that is conically widened in diameter toward the tip opening, between a flare bolt having a tapered surface that is conically narrowed in outer diameter toward the axial end and a flare nut having an inclined surface that is conically narrowed in inner diameter toward the axial end, wherein the flare nut has gear teeth on its outer circumference, a substantially cylindrical socket connected to the tip of the rotating shaft of the fastening tool has gear teeth on its outer circumference that can mesh with the gear teeth on the outer circumference of the flare nut, and the base to which the flare bolt is fixed has gear teeth on its outer circumference that can mesh with the gear teeth on the outer circumference of the socket when the flare nut is temporarily fastened to the flare bolt. The fastening tool is characterized by comprising: a socket rotating shaft capable of rotatably supporting the socket in a position where it engages with the flared portion, a first step of inserting the flared pipe into the flared nut and temporarily tightening the flared nut onto the flared bolt with the flared portion positioned between the tapered surface and the inclined surface; a second step of connecting the socket, which is connected to the tip of the rotating shaft of the fastening tool, to the socket rotating shaft so as to be rotatable, and engaging the gear teeth on the outer circumference of the socket with the gear teeth on the outer circumference of the flared nut; and a third step of rotating the socket with the fastening tool and fastening the flared nut onto the flared bolt so that the flared portion is sandwiched between the tapered surface and the inclined surface, thereby fixing the flared pipe in place.

[0007] In one embodiment of the flare nut fastening method according to the present invention, a part of the side surface of the outer circumference of the flare nut may be in the shape of a hexagonal prism that allows the flare nut to be rotated with an open wrench. [Effects of the Invention]

[0008] The present invention provides a method for fastening flare nuts that does not require a large workspace and can be fastened in a short amount of time. [Brief explanation of the drawing]

[0009] [Figure 1]This is a perspective view showing the state of a flare nut, which is fastened by the flare nut fastening method of the embodiment of this disclosure, before it is fastened to a flare bolt. [Figure 2] This diagram shows the shapes of flare nuts, flare bolts, and flare piping. [Figure 3] This diagram shows the state in which a flare nut is fastened to a flare bolt and the flare pipe is secured. [Figure 4] This is a perspective view showing the second step of the flare nut fastening method of this embodiment, in which the socket is rotatably supported on the socket rotation axis and the gear teeth on the outer circumference of the socket are engaged with the gear teeth on the outer circumference of the flare nut. [Modes for carrying out the invention]

[0010] The flare nut fastening method of this embodiment will be described below with reference to Figures 1 to 4. Figure 1 is a perspective view showing the state before the flare nut 1, which is fastened by the flare nut fastening method of this embodiment, is fastened to the flare bolt 2. As shown in Figure 1, with the flare pipe 3 inserted into the flare nut 1, the flare pipe 3 is fixed to the flare bolt 2 by fastening the flare nut 1 to the flare bolt 2 fixed to the base 4. The flare nut 1 has gear teeth 11 on its outer circumference on the base 4 side. A hexagonal portion 12, which has the shape of a hexagonal prism and can be rotated with an open wrench (not shown), is provided on a part of the side surface of the outer circumference of the flare nut 1.

[0011] In this embodiment of the flare nut fastening method, a flare nut 1 is fastened to a flare bolt 2 using a fastening tool 5 and a substantially cylindrical socket 6 having gear teeth 61 on its outer circumference. The fastening tool 5 is equipped with a rotating shaft 51, which rotates when a switch 52 is pressed. An insertion hole 62 is formed on one end face of the socket 6 for inserting the tip of the rotating shaft 51 of the fastening tool 5. The tip of the rotating shaft 51 of the fastening tool 5 has a substantially rectangular prism shape, and the insertion hole 62 of the socket 6 also has a substantially rectangular prism shape. The socket 6 is connected to the rotating shaft 51 of the fastening tool 5 by inserting the substantially rectangular prism portion of the tip of the rotating shaft 51 of the fastening tool 5 into the insertion hole 62. When the rotating shaft 51 is rotated with the socket 6 connected to the rotating shaft 51 in this way, the socket 6 also rotates together with the rotating shaft 51.

[0012] A substantially cylindrical recess 63 is formed on the other end face of the socket 6. The base 4 is provided with a substantially cylindrical socket rotation shaft 41 that can rotatably support the socket 6 by being inserted into the recess 63. The socket rotation shaft 41 is positioned so as to support the socket 6 rotatably when the gear teeth 11 on the outer circumference of the flare nut 1, which is temporarily fastened to the flare bolt 2, mesh with the gear teeth 61 on the outer circumference of the socket 6. Therefore, when the socket 6 is rotatably supported on the socket rotation shaft 41 with the flare nut 1 temporarily fastened to the flare bolt 2, the gear teeth 61 on the outer circumference of the socket 6 mesh with the gear teeth 11 on the outer circumference of the flare nut 1. When the socket 6 is rotated in this state, the flare nut 1 can be rotated.

[0013] Figure 2 shows the shapes of the flare nut 1, flare bolt 2, and flare pipe 3. Figure 2 shows cross-sectional views of the flare nut 1 and flare pipe 3, and a side view of the flare bolt 2. As shown in Figure 2, the tip of the flare pipe 3 is provided with a flare portion 31 whose diameter expands conically toward the tip opening. The tip of the flare bolt 2 is provided with a tapered surface 21 whose outer diameter decreases conically toward the axial end. A through hole 22 is formed in the radial center of the flare bolt 2, penetrating in the axial direction. The flare nut 1 is also provided with an inclined surface 13 whose inner diameter decreases conically toward the axial end. Figure 3 shows the state in which the flare nut 1 is fastened to the flare bolt 2 and the flare pipe 3 is fixed. As shown in Figure 3, when the flare nut 1 is fastened to the flare bolt 2, the flare portion 31 of the flare pipe 3 is sandwiched between the inclined surface 13 of the flare nut 1 and the tapered surface 21 of the flare bolt 2. This structure ensures that the tightening force of the flare nut 1 is evenly transmitted to the sealing portion (the inner surface of the flare portion 31), resulting in highly reliable sealing performance and preventing leakage of fluid flowing through the flare pipe 3.

[0014] In the flare nut fastening method of this embodiment, in the first step, as shown in Figure 2, the flare pipe 3 is inserted into the flare nut 1, and the flare nut 1 and flare pipe 3 are positioned so that the flared portion 31 is between the inclined surface 13 of the flare nut 1 and the tapered surface 21 of the flare bolt 2. Then, with the inner surface of the flared portion 31 of the flare pipe 3 in contact with the tapered surface 21 of the flare bolt 2, the flare nut 1 is screwed onto the flare bolt 2 by hand to perform a preliminary tightening.

[0015] Next, in the second step, after connecting the socket 6 to the tip of the rotating shaft 51 of the fastening tool 5, the socket 6 is engaged with the base 4 so that the socket rotating shaft 41 fits into the recess 63 of the socket 6, thereby supporting the socket 6 so that it can rotate on the socket rotating shaft 41. When the socket 6 is supported so that it can rotate on the socket rotating shaft 41 in this way, as shown in Figure 4, the gear teeth 61 on the outer circumference of the socket 6 mesh with the gear teeth 11 on the outer circumference of the flare nut 1.

[0016] Next, in the third step, the flare nut 1 is fastened to the flare bolt 2 by rotating the socket 6 with the fastening tool 5. By fastening the flare nut 1 to the flare bolt 2 in this way, the flare pipe 3 is fixed in place, with the flared portion 31 of the flare pipe 3 sandwiched between the inclined surface 13 of the flare nut 1 and the tapered surface 21 of the flare bolt 2, as shown in Figure 3.

[0017] The flare nut fastening method of this embodiment fastens the flare nut 1 using a fastening tool 5 and a socket 6 as described above. Compared to the method of fastening the flare nut 1 with an open wrench, this method does not require a large space for rotating the open wrench and can be fastened in a short time.

[0018] Furthermore, since a hexagonal portion 12, which has the shape of a hexagonal prism and can be rotated with an open wrench, is provided on a part of the outer circumference of the flare nut 1, even in workplaces where fastening tools 5 and sockets 6 are not available, the flare nut 1 can be attached and detached by fitting an open wrench onto the hexagonal portion 12 of the flare nut 1 and rotating it. [Explanation of symbols]

[0019] 1. Flare nut, 2. Flare bolt, 3. Flare piping, 4. Base, 5. Fastening tool, 6. Socket, 11. Gear teeth, 12. Hexagonal part, 13. Inclined surface, 21. Tapered surface, 22. Through hole, 31. Flare part, 41. Socket rotating shaft, 51. Rotating shaft, 52. Switch, 61. Gear teeth, 62. Insertion hole, 63. Recess.

Claims

1. A method for fastening a flare nut to a flare bolt in order to fix a flared pipe, which has a flared portion at its tip that expands in diameter in a conical shape toward the tip opening, between a flare bolt having a tapered surface that decreases in outer diameter in a conical shape toward the axial end and a flare nut having an inclined surface that decreases in inner diameter in a conical shape toward the axial end, wherein the flare nut is fastened to the flare bolt, The aforementioned flare nut has gear teeth on its outer circumference, The substantially cylindrical socket connected to the tip of the rotating shaft of the fastening tool has gear teeth on its outer circumference that can mesh with the gear teeth on the outer circumference of the flare nut. The base to which the flare bolt is fixed includes a socket rotation shaft that can rotatably support the socket in a position where the gear teeth on the outer circumference of the flare nut, which is temporarily fastened to the flare bolt, mesh with the gear teeth on the outer circumference of the socket. The first step involves inserting the flared pipe into the flare nut so that the flared portion is positioned between the tapered surface and the inclined surface, and then temporarily tightening the flare nut onto the flare bolt. The second step involves rotatably supporting the socket, which is connected to the tip of the rotating shaft of the fastening tool, on the socket's rotating shaft, and engaging the gear teeth on the outer circumference of the socket with the gear teeth on the outer circumference of the flare nut. A third step involves rotating the socket with the fastening tool to fasten the flare nut to the flare bolt, thereby fixing the flare pipe in a state where the flared portion is sandwiched between the tapered surface and the inclined surface. A method for fastening a flare nut, characterized by comprising the following:

2. A method for fastening a flare nut according to claim 1, A method for fastening a flare nut, characterized in that a part of the side surface of the outer circumference of the flare nut is shaped like a hexagonal prism, allowing the flare nut to be rotated with an open wrench.

Images