JPH11218274A - Housing shaped pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a bolt fastening a flange part of a housing shaped joint from being inserted incompletely into a bolt insertion hole. SOLUTION: A head 8 of a bolt 7 is formed into a T-shape, and the T-shaped head 8 is fitted into a non-circular shaped hole part 5 as one of bolt insertion holes, or let it abut against the semi-circular shaped external wall surface of a half body 2, so that a projection out of the flange part 4 of a screw part 9 is thereby eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a housing type pipe joint in which opposed flange portions of a joint body are fixed using bolts and nuts, and more particularly to a pipe joint in which a bolt is improved.

[0002]

2. Description of the Related Art A pair of halves of a joint body having a substantially semicircular cross section is formed with flange portions extending outward and laterally on both sides, and opposed flange portions are fixed using bolts and nuts. BACKGROUND ART A housing type pipe joint for connecting pipes to be connected is widely used for fire extinguishing piping and the like. In a housing type pipe joint of this type, a bolt for fixing a pair of halves is passed through a bolt insertion hole provided in a flange portion from one flange portion, and a screw portion of the bolt is extended from the other flange portion. The nut is fastened to the screw portion.

[0003] A housing type pipe joint includes a bolt head,
One of the flange portions facing each other, using a bolt including a screw portion provided on the distal end side of the stem extending from the bolt head and a bolt rotation preventing portion having a non-circular cross section formed between the screw portion and the bolt head. The nut can be tightened by inserting the bolt detent into a non-circular hole having a shape corresponding to the bolt detent formed in the above. If the bolt is not inserted correctly into the bolt insertion hole in the flange, the screw thread of the bolt will extend slightly out of the flange, and the nut will be insufficiently tightened. This causes a loosening of the joint body due to the quantity. That is, even when the bolt rotation preventing portion is seated on the flat surface of the flange portion, it is possible to tighten the nut to the thread portion of the bolt, although the amount of tightening is insufficient, the connection between the joint and the pipe. When the bolt's detent enters the non-circular portion of the flange due to external force such as vibration after the
Loosening occurs between the opposite halves of the fitting, causing water leakage.

[0004]

To solve the above-mentioned problem of water leakage from the conventional pipe joint, Japanese Patent Laid-Open Publication No. Hei 8-28764 discloses a method of increasing the axial length of a bolt detent part, and The problem is solved by making it impossible to tighten the nut when the screw portion of the bolt does not extend to the outside from the flange portion when seated on the flat surface of the flange. An object of the present invention is to solve the above-mentioned problems by simpler means than conventional ones.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional pipe joint by improving the shape of the bolt head. That is, according to the present invention, the head of the bolt is formed into a T-shape, and the T-shaped head is inserted into the same non-circular hole of the flange portion or is brought into contact with the rib of the flange portion so that the nut can be screwed into the screw portion of the bolt. The present invention employs basic technical means for enabling the tightening.

More specifically, according to the present invention, a nut is fastened to a bolt inserted through opposed flange portions of a pair of halves of a pair of halves having a substantially semicircular cross-section and symmetrical on opposed surfaces. In the housing-type fitting fixed to the end of the pipe to which the half is to be connected, the bolt comprises a T-shaped head and a threaded cylindrical stem extending from the head, The flange portion has a bolt detent, and the threaded portion of the stem allows the nut to be tightened when the T-shaped bolt head is not engaged with the bolt detent. Provide a housing type fitting which does not protrude into the housing.

Further, the present invention provides a joint body composed of a pair of halves bisected in the axial direction, a flange formed integrally on both sides of each half of the joint body and facing each other,
A housing-type pipe joint comprising a bolt and a nut inserted into a bolt insertion hole provided in the flange part to fasten the two flange parts, and arranged to straddle mutually facing ends of a pipe to which a joint body is to be connected. Wherein the bolt comprises a T-shaped head, and a cylindrical stem extending from the head and having a threaded portion at a tip end thereof, and one bolt insertion hole of a flange portion facing each other stops the T-shaped head from rotating. The T-shaped head is not inserted into the non-circular portion hole and the bolt is inserted into the bolt insertion hole of the flange portion. A housing type pipe joint is provided, wherein the threaded portion does not protrude from the other flange portion to enable the nut to be fastened.

In addition, the present invention provides a joint body consisting of a pair of halves bisected in the axial direction, a flange formed integrally on both sides of each half of the joint body and facing each other,
A housing-type pipe joint comprising a bolt and a nut inserted into a bolt insertion hole provided in the flange part to fasten the two flange parts, and arranged to straddle mutually facing ends of a pipe to which a joint body is to be connected. Wherein the bolt comprises a T-shaped head and a cylindrical stem extending from the head and having a threaded portion at a tip end thereof, and the bolt is bolted by making the longitudinal direction of the T-shaped head orthogonal to the axial direction of the joint body. When inserted into the insertion hole, the edge of the T-shaped head comes into contact with the cylindrical outer wall surface of the joint body, the T-shaped head rises from the flange portion, and the screw portion on the tip side of the stem enables the nut to be tightened. A housing type pipe joint is provided which does not protrude as much as the other flange portion.

According to the present invention, if the T-shaped head of the bolt is not properly positioned on the flange portion, it is impossible to tighten the nut to the threaded portion of the bolt, and the operator must place the bolt in the correct position. It can be easily returned. Since the T-shaped head is large, it is easy to visually recognize the correct direction, the bolt mounting work is easy for the operator, and the bolt stem below the neck of the head is all cylindrical, and can be inserted into the circular bolt insertion hole in the flange part. Therefore, the relative displacement between the opposed flange portions can be minimized, and the halves of the pair can be correctly opposed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. The housing type pipe joint 1 has a joint body 3 composed of a half body 2 and 2 'obtained by dividing a cylindrical shape by a horizontal plane including an axis, and the joint body 3 has flange portions 4 and 4 extending outward from both sides thereof. ′. Flange, 4, 4 '
The non-circular hole 5 and the circular hole 6 are formed in one of the flanges 4 and the circular hole 6 'is formed in the other flange 4'.

The bolt 7 for tightening the facing flange portions 4 and 4 'comprises a T-shaped head 8 and a cylindrical stem 10 extending from the head 8 and having a threaded portion 9 at its tip. The thickness of the T-shaped head 8 preferably corresponds to the diameter of the stem 10, and the width dimension is set to be at least twice the diameter of the stem 10. The shape of the non-circular hole portion 5 provided in the flange portion 4 is formed in a shape corresponding to the T-shaped head 8, receives the head 8, and functions to stop the bolt 7 from rotating. By taking the width of the T-shaped head 8 as large as possible in consideration of the dimensions of the flange portion 4, the bolt 8 is effectively prevented from rotating and the local load on the flange portion 4 is prevented. Let

The pipes 11, 11 to be connected face each other, the joint body 3 is put over the opposite ends thereof, the flanges 4, 4 'thereof are faced, and the bolt 7 is connected to the flanges 4, 4 'In the bolt insertion holes 5, 6, 6'. When the head 8 of the bolt 7 is correctly inserted into the non-circular hole 5, the screw portion 9 extends outside from the other flange portion 4 ′, and the nut 12 can be tightened. As shown in FIG. 4, the flanges 4, 4 'facing each other are brought into close contact with each other, and a complete pipe connection is made possible.

On the other hand, as shown in FIG. 5, when the head 8 of the bolt 7 comes into contact with the flat surface of one of the flanges 4 and is not inserted into the non-circular hole 5, the screw 9 is turned into the other flange 4 '. Does not protrude to the outside, so that the nut 12 cannot be tightened. In this case, since the T-shaped head 8 having the rotation preventing function has a large dimension in the width direction, incomplete bolt insertion is easy to visually recognize, and the returning operation to the correct position is easy.

FIGS. 6 to 8 show a second embodiment of the present invention. In this example, the circular holes 6,
Although only 6 'is provided, a pair of ribs 13, 13 spaced apart are formed on the flat surfaces of the flange portions 4, 4'. As shown in FIGS. 6 and 7, the side surface of the head 8 of the bolt 7 contacts the end surface of the rib 13 which is the rising wall portion, and the lower surface of the head 8 contacts the flat surface of the flange portion 4, so that the bolt 7 is properly prevented from rotating. When the bolt is inserted, the screw portion 9 of the bolt 7 extends outward from the flange portion 4 'to enable the nut 12 to be tightened.

On the other hand, if the bolt 7 is not correctly inserted into the bolt insertion holes 6, 6 ', the lower edge of the T-shaped head 8 shown in FIG. No further downward movement can be obtained,
Does not extend from the flange portion 4 'to the outside, so that the nut 12 cannot be tightened, so that the operator can visually recognize the incomplete insertion of the bolt 7 and immediately correct it in the correct direction. The dimension of the bolt 7 in the width direction of the head 8 is set to a dimension capable of contacting the semicircular outer wall surface of the half body 2 as shown in FIG. In the illustrated example, a pair of ribs 13 is used, but a rising wall in which these ribs are integrated may be provided on the flange portions 4 and 4 '. in this case,
When the T-shaped head 8 contacts the upper surface of the rising wall, the screw portion 9 is prevented from protruding from the flange portion 4 '. still,
The present invention is applicable not only to a housing type pipe joint but also to a split type pipe joint such as a pipe flange, which is fastened with bolts and nuts.

[Brief description of the drawings]

FIG. 1 is a sectional view of a pipe joint according to an example of the present invention.

FIG. 2 is a view as viewed from an arrow II-II in FIG. 1;

FIG. 3 is a view seen from an arrow III-III in FIG. 1;

FIG. 4 is a partial cross-sectional view of the pipe joint, showing a state where the halves are correctly tightened by bolts.

FIG. 5 is a partial cross-sectional view of the pipe joint showing a state where a bolt is incompletely inserted.

FIG. 6 is a partial front view of a pipe joint according to another example of the present invention.

FIG. 7 is a view as viewed from the arrow VII-VII in FIG. 6;

FIG. 8 is a partial cross-sectional view showing a state where a bolt is incompletely inserted.

[Explanation of symbols]

 2, 2 'half 4, 4' flange 5 Non-circular hole 6, 6 'circular hole 7 Bolt 8 T-shaped head 9 Screw part 10 Stem 11 Connection tube 12 Nut 13 Rib

Claims (9)

[Claims] 1. A joint body composed of a pair of halves bisected in the axial direction, a flange formed integrally on both sides of each half of the joint body and facing each other, and a bolt inserted into the flange. A housing-type pipe joint, comprising a bolt and a nut inserted into a hole to fasten both flange portions, the joint body being arranged to straddle mutually facing ends of a pipe to be connected, wherein the bolt has a T-shaped head. And a cylindrical stem extending from the head and having a threaded portion at the tip end thereof, wherein one of the bolt insertion holes of the flange portions facing each other receives the T-shaped head in a state where it is prevented from rotating. When the bolt is inserted into the bolt insertion hole of the flange portion without the T-shaped head being inserted into the non-circular portion hole, the screw portion at the tip end of the stem is formed into a nut. A housing-type pipe joint characterized in that it does not protrude beyond the other flange portion so as to enable fastening of the socket. 2. The bolt insertion holes provided in the opposed flange portions are symmetrical, and each half is symmetrical.
The described housing type pipe joint. 3. The housing type pipe joint according to claim 2, wherein the flange portion has a flat surface on which the T-shaped head is seated. 4. A joint body comprising a pair of halves bisected in the axial direction, a flange formed integrally on both sides of each half of the joint body and facing each other, and a bolt inserted into the flange. A housing-type pipe joint, comprising a bolt and a nut inserted into a hole to fasten both flange portions, the joint body being arranged to straddle mutually facing ends of a pipe to be connected, wherein the bolt has a T-shaped head. And a cylindrical stem extending from the head and having a threaded portion at the tip end thereof. When the bolt is inserted into the bolt insertion hole with the longitudinal direction of the T-shaped head orthogonal to the axial direction of the joint body, The edge of the head comes into contact with the cylindrical outer wall surface of the joint body, the T-shaped head rises from the flange portion, and the screw portion on the tip side of the stem does not protrude from the other flange portion. Roofing pipe fitting. 5. A rib having a rib extending from a joint body to a flange portion, wherein when a bolt is inserted into a bolt insertion hole, a side surface of a T-shaped head is in contact with a tip of the rib, a bolt is prevented from rotating, and a stem is provided. 5. The housing type pipe joint according to claim 4, wherein the threaded portion on the distal end side of the housing protrudes from the other flange portion to enable the nut to be fastened. 6. The housing type pipe joint according to claim 5, wherein the bolt insertion hole comprises a circular hole, and a T-shaped bolt head can be seated on a flat surface of the flange. 7. A half body is connected by tightening a nut to a bolt inserted into a flange part of a joint body consisting of a pair of halves having a substantially semicircular cross section and symmetrical on opposite surfaces. In a housing type fitting fixed to an end of a pipe to be fixed, a bolt comprises a T-shaped head and a cylindrical stem with a threaded portion extending from the head, and a flange portion prevents the bolt from rotating. A housing-type pipe joint having a portion, wherein the threaded portion of the stem does not protrude outside the flange so that the nut portion can be tightened when the T-shaped bolt head is not engaged with the detent portion of the bolt. . 8. A non-circular hole formed in the flange portion and having a shape corresponding to the shape of the T-shaped bolt head, wherein the bolt head is fitted into the non-circular hole. The housing type pipe joint according to claim 7, wherein 9. The pipe joint according to claim 7, wherein the bolt rotation preventing portion is a rib formed on a flat surface of the flange portion, and a side surface of the T-shaped bolt head is in contact with an end surface of the rib.