JPS5848453Y2 - A fitting for connecting the end of a small diameter metal pipe consisting of a double flare. - Google Patents

Description

[Detailed description of the invention] This invention is a metal pipe made of a relatively small diameter of about 20 cm or less, which is generally installed in large numbers as a supply path for oil and air in automobiles or various machines, equipment, devices, etc. The present invention relates to a connection joint for tuple flares having a connection structure consisting of a double flare provided at the end of a pipe.

As shown in FIG. 3, a conventional connection joint has a joint body 11 with a tapered inclined pressure receiving surface 13 protruding from the periphery of the hole end in the connection direction of the flow hole 12 in the shaft core. was.

Therefore, the double flare-16 part of the pipe 16 is connected to the pressure receiving surface 1.
3, and in this state tighten the nut 14, and when connecting the part of the double flare by pinching it between the pressure receiving surface 13 and the tightening nut 14, Double flare - thinning the 16' section, and at the same time reducing the excessive thickness due to this thinning.
Inconsistent tightening causes the bent outer peripheral edge of a portion of the double flare to expand toward the gap 15 side due to force, causing deformation, and as a result, mechanical strength often deteriorates, resulting in cracks and cracks.
In addition to causing accidents such as breakage, this deformation could impair the sealing function.

The purpose of this invention is to solve the above-mentioned problems extremely effectively by providing a small-diameter metal tube end consisting of a double flare, which has a simple structure in which an annular groove with a concave arc-shaped cross section is provided at the bottom of the pressure-receiving seat surface. The embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. The joint body 1 has a communication hole 2 extending through the shaft core, and A tapered inclined pressure-receiving seat surface 3 is protruded from the periphery of the hole end in the connection direction, and a retaining wall 4 and a front and rear circumferential wall of the retaining wall are fixed to the mating base on the outer peripheral wall side. Screw part 5 and tighten with nut 7
It has a screw portion 6 which is screwed into the screw portion 6.

A concave arc-shaped annular groove 8 provided at the bottom of the pressure-receiving seat surface 3 and connected to the pressure-receiving seat surface l is tightened as the nut 7 is screwed onto the threaded portion 6. With the bent outer peripheral edge engaged with the annular groove 8, the double flare 91 functions to be clamped together with the pressure receiving surface 3.

As described above, according to the present invention, when the nut 7 is connected by threaded tightening, the double flare 9 is secured to the annular groove 8 having a concave arc shape, thereby preventing the expanding deformation at the bent outer peripheral edge of the double flare 9. At the same time, by suppressing this deformation, the double flare 9 is prevented from thinning at the portion, making the sealing function even more effective, and improving the mechanical strength against cracks, breakage, etc. at the double flare 9' portion. It is also possible to prevent the deterioration of

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a joint for connecting the end of a small-diameter metal pipe made of double flares according to one embodiment of the present invention, with a partial cutout, showing the state of connection, and FIG. 2 is a sectional view of the same according to another embodiment of the present invention. FIG. 3 is a cross-sectional view showing a conventional example in which the connection is used with a partial cutout. FIG. 3...Pressure bearing surface, 7...Tightening nut,
8...Ring groove, 9'...Double flare.

Claims (1)

[Scope of utility model registration request] A communication hole is provided through the shaft core, and a tapered inclined pressure receiving surface is provided protruding from the peripheral edge of the hole end in the connection direction of the communication hole, and a retaining wall and the retaining wall are provided on the outer peripheral wall side. In a joint main body structure having a fixing screw part to the mating base on the front and rear peripheral walls of the body and a screw part screwed into a nut for tightening, the bottom part of the pressure receiving surface is connected to the pressure receiving surface. A joint for connecting the end of a small diameter metal pipe consisting of a double flare, characterized by having an annular groove with a concave arc shape in cross section.