JP3565407B2 - Hose fittings - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a joint fitting for connecting a metal pipe and a rubber hose on the supply side of a pressure fluid, and more particularly to a hose fitting for attaching a rubber hose by attaching a sleeve to a nipple made of a metal pipe and caulking the sleeve. .
[0002]
[Prior art]
Hose fittings used in automobiles and equipment for high-pressure fluids, for example, fittings used in power steering hoses, oil hoses, fuel hoses, etc., are required to have continuous high sealing properties to prevent leakage. . Representative examples of such fittings for hoses include those described in JP-A-57-57988 and JP-A-57-69197.
[0003]
The hose fitting described in the above publication is provided with a hole for fastening a metal pipe at the center of the end wall of the outer cylindrical portion, and the metal pipe bulges radially outward at a joint position with the hole. Bead is formed. Then, in order to attach the outer cylinder part to the metal pipe, insert the metal pipe into the hole of the end wall of the outer cylinder part, and form the metal pipe in the ring-shaped groove provided inside the end wall of the outer cylinder part. The bead projecting outward in the radial direction is fitted, and the outside of the end wall is gripped and fixed by a bead formed on the same metal pipe to be integrally attached.
[0004]
In the fitting described in the above publication, the outer peripheral surface of the rubber hose is pressed into a plurality of ring-shaped grooves having a trapezoidal vertical cross section formed on the inner peripheral surface of the outer cylinder portion, and the ring-shaped formed on the outer peripheral surface of the metal pipe. The sealing action is reliably performed by making the protrusion bite into the inner peripheral surface of the rubber hose.
[0005]
[Problems to be solved by the invention]
The joint fitting described in the above publication is such that a metal pipe is inserted into a hole in an end wall of an outer cylinder portion, and the end wall is gripped and fixed by two radially outwardly protruding beads formed on the metal pipe. Only the outer cylinder is attached. Therefore, the liquid that has penetrated between the outer peripheral surface of the metal pipe and the inner peripheral surface of the rubber hose and has reached the end wall of the outer cylindrical portion may easily leak out of the hole of the end wall. Therefore, as a conventional means for improving the sealing property, there is a method of brazing the end wall of the outer cylindrical portion and the metal pipe. However, brazing takes time and costs.
[0006]
In addition, the joint fitting described in the above publication is such that the metal pipe is inserted into the hole of the end wall of the outer cylinder part, and the end wall is merely held and fixed by two projecting beads. Cannot maintain the concentricity accurately. If the hole in the end wall of the outer cylindrical portion is made the same as the outer diameter of the metal pipe in order to eliminate the variation of concentricity, it becomes difficult to insert the metal pipe, and the assembling workability is deteriorated. On the other hand, if the hole in the outer cylinder part is enlarged, the insertion of the metal pipe becomes easy, but there is a problem that the concentricity becomes large and the liquid easily leaks.
[0007]
The present invention has been made in view of such a situation, and provides a joint fitting for a hose which not only facilitates an assembling operation of a nipple made of a metal pipe and a sleeve, but also prevents leakage of liquid and has extremely high sealability. The purpose is to:
[0008]
[Means for Solving the Problems]
The present invention has the following configuration to achieve the above object. That is, the hose fitting according to the present invention is a hose fitting comprising a nipple and a sleeve, wherein the end wall of the sleeve is fixed to a mounting portion formed by bulging the outer periphery of the nipple with a bead and a spool. In addition, the spool is formed so as to bulge into a substantially U-shaped cross section, and the side surface on the bead side forms a continuous smooth tapered surface from a vertical surface that rises almost perpendicularly to the axis. The inner wall of the end wall is formed with two tapered surfaces having different angles, and the angle of the tapered surface on the nipple side of the two tapered surfaces with respect to the axis is smaller than the angle with respect to the axis of the tapered surface located outside. Are also made smaller . The angle of the tapered surface on the spool side may be formed to be substantially the same as the angle of the tapered surface located outside the inner side surface of the end wall of the sleeve. Further, it is preferable that the angle of the taper surface on the spool side is formed at about 45 degrees with respect to the axis.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIGS. 1 and 2 show a first embodiment of the present invention, in which 1 is a nipple having one end of a metal pipe as it is, and 2 is a sleeve which is attached to an outer peripheral portion of the nipple and fixes a rubber hose by caulking. Reference numeral 3 denotes a rubber elastic O-ring disposed between the nipple 1 and the sleeve 2. The nipple 1 is configured such that the other end can be connected to a hydraulic device or the like, and has a sleeve mounting portion 10 formed by expanding in a ring shape. The nipple 1 and the sleeve 2 constitute a hose fitting by being assembled together.
[0010]
The sleeve mounting portion 10 is configured by forming a bead 10a and a spool 10b, which are formed by expanding a metal pipe in an annular shape, in parallel with a certain interval. The bead 10a is bulged in a substantially semicircular cross section, while the spool 10b is bulged in a substantially triangular cross section. Further, in the spool 10b, the side surface on the bead 10a side is a smooth tapered surface 10c, and the opposite side surface is a vertical surface 10d which is a surface perpendicular to the axis. The angle θ1 of the tapered surface 10c with respect to the axis can be arbitrarily determined. In the illustrated embodiment, the angle θ1 is formed at about 45 degrees with respect to the axis.
[0011]
On the other hand, the sleeve 2 has a cylindrical shape concentric with the nipple 1, and secures a rubber hose between the sleeve 2 and the nipple 1 by caulking radially inward in the entire circumference. An end wall 20 is provided on one end surface of the sleeve 2, and a hole 21 through which the nipple 1 is inserted is formed at the center of the end wall 20. The end wall 20 is fitted to the sleeve mounting portion 10, and the nipple 1 and the sleeve 2 are assembled integrally.
[0012]
The outer surface of the end wall 20 is formed perpendicular to the axis, but a part of the inner surface 23 is formed as a smooth tapered surface 23a and a hole which is an end of the tapered surface 23a on the nipple side. A cut-out portion 23b for fitting the rubber elastic O-ring 3 is provided on the 21 side. When the end wall 20 of the sleeve 2 is fitted to the sleeve mounting portion 10 of the nipple 1, the inner side surface 23 and the vertical surface 10d of the spool 10b are formed to be substantially flush. The angle θ2 of the tapered surface 23a is substantially the same as the angle θ1 of the tapered surface 10c of the spool 10b, and in the illustrated embodiment, is formed at about 45 degrees with respect to the axis similarly to the angle θ1.
[0013]
Therefore, when the end wall 20 of the sleeve 2 is fitted to the sleeve mounting portion 10 of the nipple 1, the concentricity of the nipple 1 and the sleeve 2 is reliably maintained by press-fitting the tapered surface 23a and the tapered surface 10c. You. The tapered surface 23a and the tapered surface 10c are crimped over the entire surface, and the outer surface of the end wall 20 is pressed by the bead 10a and is gripped and fixed between the bead 10a and the spool 10b. The notch 23b positions and fits the rubber elastic O-ring 3 between the notch 23b and the rising portion of the spool 10b, thereby improving the sealing performance between the nipple 1 and the sleeve 2.
[0014]
Next, a second embodiment of the present invention shown in FIGS. 3 and 4 will be described. In the second embodiment, the only difference is the inner surface shape of the spool 10b and the end wall 20 of the sleeve 2. Therefore, only different configurations will be described, and the same configurations will be denoted by the same reference numerals and description thereof will be omitted. The spool 11b of the nipple 1 is formed by bulging into a substantially U-shaped cross section, and the side surface on the side of the bead 10a is formed as a smooth tapered surface 11c continuous from a vertical surface 11e rising vertically to the axis. The opposite side surface is a vertical surface 11d which is a surface perpendicular to the axis. Although the angle θ1 of the tapered surface 11c can be arbitrarily determined, in the illustrated embodiment, it is formed at about 45 degrees with respect to the axis.
[0015]
On the other hand, a part of the inner side surface 23 of the end wall 20 of the sleeve 2 is formed by a tapered surface 23a and a tapered surface 23c. The angle θ2 of the tapered surface 23a with respect to the axis is substantially the same as the angle θ1 of the tapered surface 11c of the spool 11b, and the angle θ3 of the tapered surface 23c with respect to the axis is formed smaller than the tapered surface 23a. The relationship between the angles of the tapered surfaces is θ1 ≒ θ2> θ3. If the angle of each tapered surface is in the above relationship, the angle can be arbitrarily determined.
[0016]
An annular space is formed between the tapered surface 23c and the vertical surface 11e of the spool 11b, and the rubber elastic O-ring 3 is positioned and fitted into the annular space. By fitting the rubber elastic O-ring 3 in this way, an extremely high sealing property can be obtained in combination with the pressure bonding between the tapered surface 11c and the tapered surface 23a.
[0017]
5 and 6 show a third embodiment of the present invention. The third embodiment is different from the first embodiment only in the position and shape of the notch 23b. Therefore, only different configurations will be described, and the same configurations will be denoted by the same reference numerals and description thereof will be omitted.
[0018]
A part of the inner side surface 23 of the end wall 20 of the sleeve 2 has a smooth tapered surface 23a, and an annular cutout 23c is provided in the tapered surface 23a. The notch 23c is formed by cutting a side wall perpendicular to the tapered surface 23a. The rubber elastic O-ring 3 fitted in the notch 23c is pressed between the notch 23c and the tapered surface 10c. Therefore, also in this embodiment, by fitting the rubber elastic O-ring 3 into the notch 23c, an extremely high sealing property can be obtained in combination with the press-fitting of the tapered surface 10c and the tapered surface 23a.
[0019]
The fourth embodiment shown in FIG. 7 is a modification of the third embodiment, and differs from the third embodiment in that the side wall of the notch 23d is cut in parallel to the axis. . The rubber elastic O-ring 3 fitted into the notch 23d is pressed between the rubber elastic O-ring 3 and the tapered surface 10c, and as in the third embodiment, extremely high sealing performance is obtained.
[0020]
Next, an example of a method of manufacturing the hose fitting of the first embodiment will be described. First, as shown in FIG. 8, a nipple 1 in which a spool 10b is formed on a metal pipe and a sleeve 2 are manufactured in advance. The spool 10b of the nipple 1 has one end fixed to a chuck having a tapered surface having the same angle as the tapered surface 10c by protruding the tip of the pipe by an appropriate length, and pressing the punch member in the axial direction. Can be formed. On the other hand, the sleeve 2 may be manufactured by a known method such as plastic working or cutting.
[0021]
Next, the rubber elastic O-ring 3 is attached to the metal pipe on the side of the tapered surface 10c, and the metal pipe is inserted into the hole 21 of the sleeve 2 so that the tapered surface 23a of the sleeve 2 and the tapered surface 10c of the spool 10b abut each other. Then, the rubber elastic O-ring 3 is fitted into the notch 23b. Thereafter, as shown in FIG. 9, the bead 10a is formed by pressing the punch member in the axial direction with these locked states. By forming the bead 10a, the end wall 20 of the sleeve 2 is gripped and fixed between the end wall 20 and the spool 10b.
[0022]
A rubber hose may be inserted between the nipple 1 and the sleeve 2 of the hose fitting thus constructed, and the sleeve may be fixed by caulking.
[0023]
【The invention's effect】
As is apparent from the above description, according to the present invention, the spool 10b of the nipple 1 and the inner surface of the end wall 20 of the sleeve 2 are crimped by a taper surface having substantially the same angle, and a rubber elastic O-ring is provided between the two. Since the intervening structure is provided, the sealing performance is significantly improved, and leakage of the liquid can be prevented. In addition, since the taper surface having substantially the same angle is press-bonded between the spool 10b of the nipple 1 and the inner surface of the end wall 20 of the sleeve 2, the concentricity between the nipple and the sleeve is improved, and the sealing performance is further improved.
[Brief description of the drawings]
FIG. 1 is a sectional view of a joint fitting for a rubber hose according to the present invention.
FIG. 2 is an explanatory sectional view of an upper half of a state in which a nipple and a sleeve are separated.
FIG. 3 is a sectional view of a joint fitting for a rubber hose according to a second embodiment of the present invention.
FIG. 4 is an explanatory sectional view of an upper half of a state in which a nipple and a sleeve of FIG. 3 are separated.
FIG. 5 is a sectional view of a joint fitting for a rubber hose according to a third embodiment of the present invention.
FIG. 6 is an explanatory cross-sectional view of an upper half of a state where a nipple and a sleeve of FIG. 5 are separated.
FIG. 7 is an explanatory sectional view of an upper half of a fourth embodiment of the present invention in which a nipple and a sleeve are separated.
FIG. 8 is an explanatory sectional view showing an assembled state.
FIG. 9 is an explanatory sectional view showing a completed state.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 nipple 2 sleeve 3 rubber elastic O-ring 10 sleeve mounting portion 10 a bead 10 b spool 10 c taper surface 10 d vertical surface 11 b spool 11 c taper surface 11 d vertical surface 20 end wall 21 hole 23 inner surface 23 a taper surface 23 b cutout portion 23 c taper surface 23 d cutout Department

Claims (3)

A hose fitting comprising a nipple and a sleeve, wherein the end wall of the sleeve is fixed to a mounting portion formed by expanding the outer periphery of the nipple to a bead and a spool. The bead side surface forms a continuous smooth tapered surface from a vertical surface that rises almost perpendicularly to the axis, while the inner surface of the end wall of the sleeve has two tapered surfaces with different angles. A joint fitting for a hose, characterized in that a surface is formed, and an angle of the tapered surface on the nipple side of the two tapered surfaces with respect to the axis is smaller than an angle of the tapered surface located outside with respect to the axis . The hose fitting according to claim 1, wherein the angle of the tapered surface on the spool side is substantially the same as the angle of the tapered surface located outside the inner side surface of the end wall of the sleeve. The hose fitting according to claim 1 or 2, wherein the angle of the tapered surface on the spool side is formed at about 45 degrees with respect to the axis.

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