JPH0673581U - Union fittings - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] A union fitting that is suitable for use as a fitting for circulation of ultrapure water, for example, without creating a gap that causes retention of fluid on the abutting surface of the sleeve tube. [Structure] A sleeve tube 3 which is inserted into an insertion hole 2 of a cap nut 1 and a flange portion 5 of which is brought into contact with an inner wall surface of the cap nut,
The threaded portion 9 formed on the outer peripheral surface of the flange portion 8 on the threaded portion 4
The annular groove 11 is formed on the abutting surface 10 of either one of the sleeve tube 7 and the sleeve tube 7, and the slit portion 13 is formed from this to the flow path surface 12 of the sleeve tube 7, and the annular groove is sealed. Ring packing 1
4 is fitted with a rib 16 protruding from the outer peripheral portion of a ring portion 15 having a substantially circular cross section, which is substantially flush with the abutting surface 10.
In addition, the rib 16 is substantially flush with the abutting surface 10.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cap nut type union pipe joint that does not generate retained water that deteriorates the water quality between the liquid contact surface of the pipe inner surface and the sealing ring packing so that it is suitable for the flow of ultrapure water. is there.

[0002]

[Prior art]

 In general, disassembled cap nut type union pipe joints have been widely used for joining pipes. Specifically, as shown in FIG. 4, the sleeve tube 2 inserted into and locked by the cap nut 1 and the sleeve tube 3 screwed into the cap nut 1 are butted against each other and formed on the butted surface of the sleeve tube 3. A ring-shaped packing 5 for sealing is fitted in the formed annular groove 4 is used.

[0003]

[Problems to be solved by the device]

 In the above-mentioned union pipe joint, in order to enhance the sealing effect of the sealing ring-shaped packing 5, the ring-shaped packing 5 has a sufficient thickness. On the other hand, however, the ring-shaped packing 5 is compressed and elastically deformed so as to project from the annular recessed groove 4 to form a gap between the sleeve pipes 2 and 3, and the gap causes the fluid to stay. For this reason, for example, when it was used as a pipe joint for the distribution of ultrapure water, it deteriorated the water quality in the long term and was not suitable for use.

[0004]

[Means for Solving the Problems]

 In the union pipe joint according to the present invention, the sleeve pipe is inserted through the insertion hole of the cap nut and the flange portion abuts the inner wall surface of the cap nut, and the threaded portion of the inner peripheral surface of the cap nut has the outer peripheral surface of the flange portion. An annular groove is formed on one of the butting surfaces with the sleeve tube to which the threaded portion formed in is screwed, and a slit is formed from this annular groove to the flow path surface of the sleeve tube. The ring-shaped packing for sealing is fitted in the annular groove, and the ring-shaped packing is provided with a rib protruding from the outer peripheral portion of the ring having a substantially circular cross section, which is fitted in the slit portion. When the packing is compressed, the ring portion is substantially flush with the abutting surface, and the rib is substantially flush with the abutting surface, and its tip portion is substantially flush with the flow path surface of the sleeve pipe. With such a configuration, there is no gap for retaining the fluid between the abutting surfaces, and the flow passage surface of the abutting portion of the sleeve pipe is formed with irregularities for retaining the fluid. Since there is no such problem, the fluid can be circulated smoothly.

It is more preferable that the amount of compression of the ring portion of the ring-shaped packing when the sleeve tubes are butted is 25 to 30% of the diameter of the ring portion. By doing so, the amount of compression of the ring portion at the abutting portion of the sleeve tube becomes appropriate, and the sleeve tube becomes more surely substantially flush with the abutting surface of the sleeve tube, and the sealing performance is further improved.

[0006]

[Action]

 According to this invention, when the ring-shaped packing is compressed and elastically deformed, the ring portion whose cross section is substantially circular is substantially flush with the abutting surface of the sleeve tube, and the rib is also abutting surface of the sleeve tube. Since they are substantially flush with each other, they do not protrude from the annular groove, and no gap is created between the abutting surfaces of the sleeve tube.

Further, since the tip of the rib is substantially flush with the flow path surface of the sleeve tube, the flow path surface of the butted portion of the sleeve tube is not formed with irregularities for retaining the fluid. Therefore, the fluid flowing through the pipeline will not be accumulated.

[0008]

【Example】

 Next, an embodiment of the union joint of the present invention will be described in detail with reference to the drawings.

Reference numeral 1 denotes a cap nut, which has an insertion hole 2 through which the sleeve tube 3 is inserted, and a threaded portion 4 formed on the inner peripheral surface thereof. The sleeve tube 3 is inserted into the insertion hole 2 of the cap nut 1, and the flange portion 5 is in contact with the inner wall surface 6 of the cap nut 1. Reference numeral 7 denotes a sleeve pipe, and a screw portion 9 formed on the outer peripheral surface of a flange portion 8 is screwed to the screw portion 4 of the cap nut 1.

An annular groove 11 is formed in the abutting surface 10 of the sleeve tube 7 with the sleeve tube 3, and a slit portion 13 is formed from the annular groove 11 to the flow path surface 12 of the sleeve tube 7.

Reference numeral 14 is a ring-shaped packing for sealing made of, for example, a rubber elastic material, and the ring-shaped packing 14 is fitted to the slit portion 13 from an outer peripheral portion of a ring portion 15 having a substantially circular cross section. The rib 16 is provided so as to project. In this ring-shaped packing 14, when the ring portion 15 is fitted into the annular groove 11 and compressed by the butting of the sleeve tubes 3 and 7, the ring portion 15 is substantially flush with the butting surface 10 of the sleeve tubes 3 and 7. Is made. Further, the rib 16 is fitted into the slit portion 13 and becomes substantially flush with the butting surface 10 when compressed by the butting of the sleeve tubes 3 and 7, and the tip portion 17 of the rib 16 is provided. , 7 and 7 are substantially flush with the flow path surface 12.

When the sleeve tubes 3 and 7 are butted against each other, the compression amount of the ring portion 15 of the ring-shaped packing 14 having a substantially circular cross section is 25 to 30% of the diameter of the ring portion 15. The formed ring portion 15 is in close contact with the groove wall surface of the annular groove 11. Reference numerals 18 and 19 are flow pipes inserted into the sleeve pipes 3 and 7 to be connected thereto. Although the sleeve pipes 3 and 7 in the above example are used as receiving ports for the flow pipes 18 and 19, they may be used as outlets.

[0013]

[Effect of device]

 According to this invention, since it has the above configuration, when the ring-shaped packing is compressed and elastically deformed, the ring portion having a substantially circular cross section is substantially flush with the abutting surface of the sleeve tube. Since the ribs are substantially flush with the abutting surface of the sleeve tube, they do not protrude from the annular groove and no gap is created between the abutting surfaces of the sleeve tube.

Further, since the tip end portion of the rib is substantially flush with the flow passage surface of the sleeve pipe, the flow passage surface at the abutting portion of the sleeve pipe does not have unevenness for retaining the fluid. . Therefore, the fluid flowing through the pipeline will not be accumulated. Therefore, for example, in the flow of ultrapure water, accumulated water that deteriorates the water quality will not be generated even after long-term use.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a union pipe joint of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a ring-shaped packing is fitted in an annular groove before compression.

FIG. 3 is a cross-sectional view showing a state in which the ring-shaped packing is compressed by the butting of sleeve tubes.

FIG. 4 is a sectional view showing an example of a conventional union pipe joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cap nut 2 Insertion hole 3 and 7 Sleeve tube 4 and 9 Screw part 5 and 8 Flange part 10 Abutment surface 11 Annular groove 12 Flow path surface 13 Slit part 14 Ring packing 15 Ring part 16 Rib 17 Tip part

Claims (2)

[Scope of utility model registration request] 1. A sleeve tube which is inserted into an insertion hole of a cap nut and has a flange portion abutting an inner wall surface of the cap nut, and a thread portion of an inner peripheral surface of the cap nut, which is formed on an outer peripheral surface of the flange portion. An annular groove is formed on one of the abutting surfaces with the sleeve tube to which the screw part is screwed, and a slit is formed from this annular groove to the flow path surface of the sleeve tube, and the annular groove is sealed. The ring-shaped packing is fitted, and the ring-shaped packing is provided with ribs protruding from the outer peripheral portion of the ring portion having a substantially circular cross section, and the ring-shaped packing is compressed. At this time, the ring portion is substantially flush with the abutting surface, the rib is substantially flush with the abutting surface, and the tip portion thereof is substantially flush with the flow passage surface of the sleeve tube. Pipe fittings. 2. The union pipe joint according to claim 1, wherein the compression amount of the ring portion of the ring-shaped packing when the sleeve pipes are butted is 25 to 30% of the diameter of the ring portion.