JP2011169408A - Rotary joint and swivel elbow using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary joint, which is reduced in size, weight and cost without impairing oscillating and rotating functions. <P>SOLUTION: In the rotary joint, a nose of an insert is fitted to a nipple so that the both are rotatable in the radial direction of a shaft. The inside diameter of the nipple is set larger than the outside diameter of the nose, the nose includes a circumferential groove of a trapezoidal sectional shape opened on the main surface side, and a plurality of steel balls are fitted to the groove. An annular retainer having an inclined surface facing the trapezoidal circumferential groove surface is fitted across the steel balls, and a locking member is provided on the outside of the annular retainer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a joint used for a fluid flow path, and more particularly to a joint for an automobile, a construction machine, a machine tool, and the like, and in particular, swinging and rotating suitable for use in a narrow space. Related rotary joints and swivel elbows using the same.

In general, there are steel pipes, hoses or tubes (hereinafter referred to as pipes unless there is a problem) as means for transferring fluid. For example, in a car or the like, various fluids are frequently used, but all of them are used in a narrow space. For this reason, the required joint is required to be small in size and to allow the pipes before and after the joint to swing and rotate. However, there were often cases where conventional joints could not cope. This is because the structure of the conventional joint is large and has a problem with respect to swinging / rotating and bending functions.

  However, rotary joints for preventing breakage and twisting of pipes have been proposed. That is, as an example of providing the rotation function of the tube, there is a structure in which the front and rear of the joint can be rotated, and there is a swivel elbow that provides a swinging and bending function.

  FIG.1 and FIG.2 is a conceptual diagram of the rotary joint and swivel elbow concerning a prior art (nonpatent literature 1).

  In the rotary joint 40 of FIG. 1, the nose 41A of the insert 41 and the socket 42 are fitted, and a commercially available thrust bearing 43 steel ball 43A retainer 43B) is sandwiched so that the nipple 44 is fitted. The use of the thrust bearing 43 is intended to reduce the frictional resistance between the insert 41 and the nipple 44 generated by the axial pulling force generated by the pressure of the fluid flowing inside.

  For this reason, the outer diameter dimension is determined by the size of the thrust bearing 43 to be used, and the outer diameter of the rotary joint 40 is large and heavy. This has the disadvantage that the price of the rotary joint 40 is high, and technically, the assemblability of the rotary joint 40 is poor. In the figure, 45 is a set screw, 46 is an O-ring, 47 is a backup ring, 48 is a cut washer, 48A is a ring, and 49 is a dust seal.

  In the swivel elbow 50 of FIG. 2, an elbow 53 is fitted into the perforated portion 52 of the shaft 51, and the elbow 53 is rotatable with respect to the axial direction of the shaft 51. An O-ring 54 and a dust seal 55 are interposed between the two so as to be rotatable. In the figure, 56 is a union nut provided on the elbow 53, 57 is a housing, 58 is a washer for preventing the elbow 53 from coming off, and 59 is a stop ring.

  In the swivel elbow 50 having such a structure, the elbow 53 has only one rotation axis. Therefore, in order to increase the degree of freedom in the rotational direction, the rotary joint 40 of FIG. However, since the rotary joint 40 to be connected has a large outer shape and is heavy as described above, the swivel elbow 50 to which the rotary joint 40 is assembled has a drawback that the turning radius is large and heavy, and the price is high.

Catalog of ABC Coupling Industry Co., Ltd. (http://www.abc-coupling.co.jp/)

  The first object of the present invention is to provide a rotary joint that is small, light, and inexpensive without impairing the swinging / rotating function.

  A second object of the present invention is to provide a crank-type swivel elbow that is small, light and inexpensive, and has a high degree of freedom of rocking and rotation.

  A rotary joint according to a first aspect of the present invention is a rotary joint in which a nose of an insert is fitted into a nipple and both of them can be rotated in the radial direction of the shaft, and the inner diameter of the nipple is larger than the outer diameter of the nose. None, this nose is formed with a circumferential groove whose front side is open, a plurality of steel balls are fitted in this groove, and then an annular retainer having an inclined surface facing the circumferential groove surface is fitted across this steel ball Further, a locking member is provided outside the annular retainer.

  The swivel elbow according to the second aspect of the present invention is provided with a perforated portion in the elbow portion of the shaft, the housing is rotatably fitted to the perforated portion, and the noses of the inserts A and B are fitted in the shaft and the housing, respectively. The swivel elbow is configured to be rotatable in the radial direction of the shaft, and the inner diameters of the shaft and the housing are made larger than the respective outer diameters of the respective noses, and a circumferential groove whose surface side is open to each of the noses. A plurality of steel balls are fitted in the groove, and then an annular retainer having an inclined surface facing the circumferential groove surface is fitted between the steel balls, and a locking member is provided outside the annular retainer. It will be.

  The rotary joint which is the first of the present invention uses a special structure between the insert and the nipple without using the thrust bearing used between the insert and the nipple and the socket, which is a conventional essential structure. Is achieved. In other words, the retainer and insert that sandwich the steel ball are formed with opposing inclined surfaces, and the steel ball is sandwiched between these surfaces. Therefore, the rotary joint can be easily assembled by incorporating the steel ball. There is no need for a holder such as a bearing, and the outer shape of the joint can be further reduced.

  Since the rotary joint can be made small, the swivel elbow in which the rotary joint is incorporated can freely rotate with a small turning radius, and the effect of preventing contact and interference between the housing side and the shaft side during free rotation. It also has.

FIG. 1 is a conceptual diagram of a rotary joint according to the prior art. FIG. 2 is a conceptual diagram of a swivel elbow according to the prior art. FIG. 3 is a half sectional view of the first rotary joint of the present invention. FIG. 4 is an enlarged cross-sectional view of the main part of FIG. FIG. 5 is a partially cut cross-sectional view of an L-shaped swivel elbow showing an example of the second swivel elbow of the present invention. FIG. 6 is a partially cut cross-sectional view of a crank-type swivel elbow showing an example of the second swivel elbow of the present invention.

  When the first rotary joint of the present invention is mainly described, the use of a commercially available thrust bearing, which is the cause of the increase in outer shape, is stopped, a circumferential groove is formed on the insert surface, and a steel ball is fitted therein, and The retainer, the steel ball, and the circumferential groove of the insert have a structure in which the steel ball is in contact with an angle at which the steel ball does not spill and the retainer is connected to the nipple such as a screw or a ring. It has a structure that cannot be removed by the locking means. Therefore, the outer shape of the rotary joint is small, light weight is realized, and the insert and nipple can rotate with each other with low torque even if the drawing force is generated by the internal pressure generated when the fluid is passed. It is what. In addition, as a steel ball, not only a metal ball but a so-called bearing material such as a ceramic ball can be used. The circumferential groove is not particularly limited, but is usually a circumferential groove having a trapezoidal shape or a spherical shape in cross section.

  The second swivel elbow of the present invention is characterized by incorporating this structure, and can be exemplified by an L-type or crank-type swivel elbow.

  FIG. 3 is a half-cut sectional view showing an example of the first rotary joint 10 of the present invention, and FIG. 4 is an enlarged sectional view of a main part. In the figure, reference numeral 1 denotes a nipple, which has a structure in which the nose a of the insert A is fitted into the inner diameter of the nipple 1. In this example, the inner diameter of the nipple 1 is made larger than the outer diameter of the nose a, and a space is provided between them. In this nose a, a circumferential groove 2 having a trapezoidal cross section whose surface side is open is formed here. Then, a plurality of steel balls 3 are fitted into the groove 2. Next, the rotary retainer is formed by fitting an annular retainer 4 having an inclined surface 4A facing the inclined surface 2A of the circumferential groove 2 with the steel ball 3 interposed therebetween, and further including a locking member 5 outside the annular retainer 4. .

  In the illustrated example, the locking member 5 is a wire ring and is fitted in a circumferential groove 6 formed on the inner diameter surface of the nipple 1, and the annular retainer 4 is pressed down to prevent it from coming off. . In this example, a nut 7 (pipe connecting means) is mounted on the insert A, and a screw 8 (pipe connecting means) is engraved on the nipple 1 for use in connection with other pipes and equipment not shown. This is an example configured as described above. Further, 9 is an O-ring, and 9A is a backup ring, which ensures rotation of the nose a.

  The rotary joint 10 which is the first of the present invention does not use the thrust bearing used between the insert, the nipple and the socket, which is a conventional essential structure, but the annular retainer 4 sandwiching the steel ball 3 and the nose a of the insert A. The inclined surfaces 4A and 2A facing each other are formed, and the steel ball 3 is sandwiched between the surfaces, and the rotary joint 10 can be easily assembled by incorporating the bearing 3 therein, and the outer shape of the joint 10 is smaller. And it can be lightened.

  Specifically, in a 1/4 size rotary joint, a conventional product using a thrust bearing has a maximum outer diameter of 32 mm, a total length of 73 mm, and a weight of 200 g. These are 22 mm, 57 mm, and 90 g, and it is proved that the size and weight can be reduced.

  Moreover, even if a drawing force is generated by the internal pressure generated when the fluid is passed, the steel balls 3 are sandwiched between the inclined surfaces 4A and 2A facing each other, so that they do not come out, and the insert A and the nipple 1 Have features that rotate with each other at low torque.

  FIG. 5 is a partially cut cross-sectional view of an L-shaped swivel elbow 20 that is an example of the second swivel elbow of the present invention. In the figure, 21 is a shaft and 22 is an L-shaped elbow. If the L-shaped swivel elbow 20 is compared with the rotary joint, the structure is similar to the structure in which the nipple 1 is bent by 90 degrees, and the screws 30 and 31 are engraved so as to be connected to other pipes and equipment. It was established.

  In the figure, the inner diameter of the elbow 22 is made larger than the outer diameter of the nose a of the insert A, and a circumferential groove 25 is formed in the nose a in the same manner as in the first embodiment. A ball 26 is fitted, and then an annular retainer 27 having an inclined surface 27A facing the surface 25A of the circumferential groove 25 is fitted with the steel ball 26 interposed therebetween, and a locking member 28 is provided outside the annular retainer 27. A swivel elbow 20 of the type. The inclined surface 27A is formed on the inner diameter side of the annular retainer 27, and the steel ball 26 is sandwiched between the inclined surfaces 25A of the circumferential groove 25. Since the relationship between the annular retainer 27, the steel ball 26, and the circumferential groove 25, the function thereof, and the like have been described in detail in the first embodiment, the description thereof will be omitted. Reference numeral 28 denotes a circumferential groove that governs the wire ring (locking member) 29.

  FIG. 6 is a partially cut cross-sectional view of a crank-type swivel elbow 20 that is an example of the second swivel elbow of the present invention. In the figure, 21 is a shaft, and 22 is an elbow joined to the shaft 21 in an L shape. The elbow 22 is formed with a perforated portion 23 serving as a fluid passage. A swivel elbow in which a housing 24 is rotatably fitted to the perforated portion 23, and noses a and b of inserts A and B are fitted to the shaft 21 and the housing 24, respectively, so that both can be rotated in the radial direction of the shaft. is there.

  The structure is substantially the same as in the second embodiment, but the inner diameters of the shaft 21 and the housing 24 are made larger than the outer diameters of the respective noses a and b, and the surface side is opened to the respective noses a and b. A circumferential groove 25 having a trapezoidal cross section is formed, and a plurality of steel balls 26 are fitted into the groove 25, and then an inclined surface 27A facing the surface 25A of the trapezoidal circumferential groove 25 is sandwiched between the steel balls 26. This is a crank-type swivel elbow 20 in which an annular retainer 27 is fitted and a locking member 28 is provided outside the annular retainer 27. The inclined surface 27A is formed on the inner diameter side of the annular retainer 27, and the steel ball 26 is sandwiched between the inclined surfaces 25A of the circumferential groove 25. Since the relationship between the annular retainer 27, the steel ball 26, and the circumferential groove 25, the function thereof, and the like have been described in detail in the first embodiment, the description thereof will be omitted. Reference numeral 28 denotes a circumferential groove that governs the wire ring (locking member) 29.

  The swivel elbow 20 shown in the figure is also used for connection with other pipes and equipment as in the rotary joint 10 of the first embodiment. Therefore, in the example shown, the nut 30 is provided on the insert A as a pipe connecting means. An example in which a screw 31 is engraved on the nose b side is shown. Reference numeral 32 denotes an O-ring, and reference numeral 32A denotes a backup ring. The O-ring 32 ensures the rotation of the housing 24 and the rotation of the noses A and B. In addition, 33 is a washer, 34 is a C-shaped retaining ring, and 35 is a dust seal.

  The swivel elbow incorporating the rotary joint, which is the first aspect of the present invention, particularly a crank-type swivel elbow, does not interfere with the housing side and the shaft side during rotation, and has a small turning radius. A free rotation was obtained.

  The present invention provides a rotary joint as described above and a swivel elbow to which the rotary joint is applied, and a swingable and rotatable rotary joint suitable for use in a narrow space such as an automobile, a construction machine, and a machine tool. A swivel elbow is provided. It is particularly easy to assemble, achieves downsizing, and achieves weight reduction, and its industrial value is extremely high.

A, B Insert a, b Nose 1 Nipple 2, 25 Circumferential groove 2A, 25A Inclined surface 3 of circumferential groove, 26 Steel ball 4, 27 Annular retainer 4A, 27A Inclined surface 5, 28 of annular retainer Locking members 6, 29 Circumferential groove 7, 30 Nut 8, 31 Screw 9, 32 O-ring 9A, 32A Backup ring 10 Rotary joint 20 Crank-type swivel elbow 21 Shaft 22 Elbow 23 Perforated part 24 Housing

Claims (13)

  A rotary joint in which the nose of the insert A is fitted into a nipple and both of them can be rotated in the radial direction of the shaft. The inner diameter of the nipple is made larger than the outer diameter of the nose, and the surface side is opened to the nose. A circumferential groove is formed, and a plurality of steel balls are fitted into the groove, and then an annular retainer having an inclined surface facing the circumferential groove surface is fitted between the steel balls, and a locking member is provided outside the annular retainer. A rotary joint with   The rotary joint according to claim 1, wherein an inclined surface is formed on an inner diameter side of the annular retainer, and a steel ball is sandwiched between the circumferential groove.   The rotary joint according to claim 1 or 2, wherein the insert A is provided with pipe connecting means.   The rotary joint according to claim 3, wherein the pipe connecting means is a nut.   The rotary joint according to claim 1 or 2, further comprising a pipe connecting means on the nipple.   The rotary joint according to claim 5, wherein the pipe connecting means is a screw.   A perforated portion is provided in the elbow portion of the shaft, and the housing is rotatably fitted to the perforated portion. The noses of the inserts A and B are fitted in the shaft and the housing, respectively, so that both can be rotated in the radial direction of the shaft. A swivel elbow, wherein the inner diameter of the shaft and the housing is made larger than the outer diameters of the respective noses, and a circumferential groove having an open surface side is formed in each nose, and a plurality of steel balls are formed in the grooves. A swivel elbow that is fitted with an annular retainer having an inclined surface that faces the circumferential groove surface with the steel ball interposed therebetween, and further includes a locking member outside the annular retainer.   The swivel elbow according to claim 7, wherein the elbow is joined to the shaft in an L shape.   The swivel elbow according to claim 7, wherein an inclined surface is formed on the inner diameter side of the annular retainer, and a steel ball is sandwiched between the circumferential groove.   The swivel elbow according to claim 7 or 8, wherein the insert A is provided with pipe connecting means.   The swivel elbow according to claim 10, wherein the pipe connecting means is a nut.   The swivel elbow according to claim 7 or 8, wherein a pipe connecting means is provided on the nose of the insert B.   The swivel elbow according to claim 12, wherein the pipe connecting means is a screw.

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