JP2000246377A - Pipe and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel pipe which can lighten weight of a pipe compared with the conventional one, reduce water conducting resistance, and reduce working burden. SOLUTION: A pipe 10 comprises a straight pipe part 11 extending straight from a mounting metallic fixture 20 at approximately the same diameter, a curved part 12 after the straight pipe part 11, and a tapered part 13 formed after the curved part 12 in a manner to increase the pipe diameter gradually. Furthermore, a tip end 14 of an approximately straight pipe shape which is inserted into the inside of the mounting metallic fixture 20 to expand the end in diameter and is fitted with the mounting metallic fixture 20 from the inside, is formed on a tip side of the straight pipe part 11. Also, a base end 15 of an approximately straight pipe shape, which is inserted into the inside of a mounting metallic fixture 30 to expand the end in diameter and is fitted with the mounting metallic fixture 30 from the inside, is formed on the base end side of the tapered part 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pipe spear and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, as a part of fire-fighting equipment, a pipe spear which constitutes a part of a water discharge nozzle or is connected to a base of the water discharge nozzle has been manufactured. Pipe spears usually connect the base end to the tip of a fire hose and connect a water discharge nozzle to the tip so that water and chemicals sent from the fire hose are released from the water discharge nozzle. is there. The pipe spear is made of a casting formed by a casting method or the like. The base end of this cast pipe spear is integrally formed with a base end side mounting portion for mounting a fitting attached to the fire hose by screwing or the like, and a water discharge nozzle is connected to a front end portion of the main body. To form a front-end-side mounting portion.

A typical tube spear that has been used for many years is a straight tubular casting with a larger diameter inlet at the proximal end and a smaller diameter outlet at the distal end. However, since the water pressure at the time of water discharge is greatly exerted on the pipe spear, the burden on the worker who carries out the water discharge work with the pipe spear is large, so it is generally called a non-reaction type in order to reduce the burden on the worker. Pipe spears curved in a predetermined direction are frequently used. This non-rebound type pipe spear has a curved shape to give directionality to the water guide direction and reduce the movement of the pipe spear due to the recoil at the time of water discharge.

[0004]

However, since the pipe spears described above are all formed by casting, the overall weight is large, and even if a light alloy such as an aluminum alloy is used, it can be handled. There is a problem that it is very difficult.

[0005] Further, it is very difficult for the pipe spear formed by casting to form the inner surface of the inner water channel smoothly, and in order to smooth the inner surface of the water channel, a separate polishing process is required. However, in the case of ordinary pipe spears, the current situation is that polishing is not performed due to the difficulty of polishing processing and increase in processing cost, and it is commercialized as it is on the casting surface, so that the water transmission resistance increases, and accordingly, The burden on the operator for supporting the water discharge is extremely large.

In addition, in the case of a cast pipe spear, the base end portion and the front end portion are integrally formed, so that the base end portion and the front end portion need to have a sufficient thickness. There is a problem that steps are formed on the inner surfaces of the inlet provided inside the inside and the outlet provided inside the distal end portion, and these steps further increase water conveyance resistance. At present, the pipe spear must be carried by two people,
Even if two people possess, the work load is very large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a new pipe capable of reducing the weight of the pipe spear as compared with the conventional one, reducing the water flow resistance, and reducing the work load. There is in providing a spear.

[0008]

In order to solve the above-mentioned problems, the present invention takes measures such that an inlet diameter and an outlet diameter are different due to a tapered portion formed by gradually changing the diameter of a metal pipe. And a curved portion is formed in at least a part of the pipe. Since it is composed of a pipe having a curved portion, the water conduit can be formed smoothly and the inner surface of the pipe spear can be easily formed smoothly, so that the water resistance can be reduced and the weight can be reduced. Since it is easy, the burden on the operator can be significantly reduced as compared with the conventional art, and the manufacturing cost can be reduced as a whole. Here, it is preferable that the curved portion is formed by plastic working. By forming the curved portion by plastic working, the curved portion can be easily provided without reducing the rigidity of the pipe. Further, it is preferable that the tapered portion is also formed by plastic working.

In the first aspect, it is preferable that the curved portion is formed at a portion that does not overlap with the tapered portion. Since the curved portion is formed in a portion that does not overlap with the tapered portion, the curved portion can be easily formed by plastic working.

[0010] In claim 1 or 2, it is preferable that an end of the pipe is fixed to an inner surface of a fitting. By fixing the end of the pipe to the inner surface of the fitting, it is possible to reduce the unevenness of the wall of the water conduit at the end of the pipe spear, thereby further reducing the water transmission resistance and further reducing the burden on the operator. be able to.

According to a third aspect of the present invention, it is preferable that the pipe and the fitting have a fixing structure in which an end of the pipe is enlarged in diameter inside the fitting. By expanding the diameter of the end of the pipe inside the mounting bracket and fixing it, the connection can be made without increasing the burden and cost of the fixing work, and the pipe is fixed by the stress that expands the pipe even if water pressure is applied inside the pipe spear. Since the parts are not easily removed, the withstand voltage can be easily improved. Here, particularly, the tip of the end of the pipe is deformed so as to spread in a trumpet shape along the inner surface of the fitting, or the inner surface of the fitting and the outer surface of the pipe are fixed so as to be in close contact with each other in an uneven manner. This is effective in increasing the breakdown voltage. As an example of the latter, there is a case where a groove extending in the circumferential direction is formed on the inner surface of the mounting bracket so that the wall surface of the pipe is deformed in accordance with the groove.

Next, the pipe spear is characterized in that the end of the metal pipe is pushed out from the inside and fixed to the inner surface of the mounting bracket. By pushing the end of the pipe from the inside and fixing it to the inner surface of the mounting bracket, the wall surface of the water conduit can be formed smoothly even at the connection portion to another member in the pipe spear, so that the water transmission resistance can be reduced. .

According to claim 4 or 5, the structure for fixing the end portion of the pipe to the inner surface of the mounting bracket has a concave-convex joint surface whose joint diameter increases or decreases in the axial direction of the pipe. Is preferred. This makes it possible to sufficiently secure the mounting strength between the pipe and the mounting bracket without performing welding or the like.

Next, there is provided a method for manufacturing a pipe spear, wherein a bent portion is formed by bending a metal pipe by plastic working. By bending the pipe by plastic working, a smooth water conduit can be formed while maintaining the rigidity of the pipe, and the smoothness of the inner surface of the water conduit can be easily obtained.

According to a seventh aspect of the present invention, it is preferable that the curved portion is formed after forming a tapered portion in which the pipe diameter is gradually changed by plastic working on the pipe. Since the straight pipe can be tapered, the taper can be easily processed.

In the present invention, it is preferable that a fitting is attached to an end of the pipe before the curved portion is formed. Thus, the centering operation and the mounting operation when the mounting bracket is mounted can be easily performed. .

In each of the above means, it is preferable to form a tapered portion in which the pipe diameter is gradually changed by plastic working on the pipe. Further, it is preferable that the end of the pipe is inserted into the inside of the mounting bracket, and the end of the pipe is enlarged to fix the pipe to the mounting bracket.

In each of the above means, the tapered portion of the pipe processed in the tapering step and the bent portion of the pipe bent in the bending step are processed so as not to overlap each other. By doing
The formation of the curved portion can be easily performed.

[0019]

Next, an embodiment according to the present invention will be described in detail. FIG. 1 is a side view showing the appearance of the pipe spear of the present embodiment, and FIG. 2 is a longitudinal sectional view showing the internal structure of the pipe spear of the present embodiment. This embodiment is, for example, a rolling process made of a metal such as aluminum alloy and stainless steel,
A pipe 10 formed by extrusion, drawing, or other plastic processing, and fittings 20, 30 similarly formed of a metal such as an aluminum alloy or stainless steel and formed by forging, for example, and attached to the pipe 10. And the handle 40 provided.

The pipe 10 has a straight pipe 11 extending straight from the mounting bracket 20 and having substantially the same diameter.
1 and a curved portion 12 which is curved and a tapered portion 13 which is formed so that the pipe diameter gradually increases following the curved portion 12. Further, as shown in FIG. 2, at the distal end side of the straight pipe portion 11, a substantially straight tubular distal end portion which is inserted into the inside of the mounting bracket 20 and has an enlarged diameter and is engaged with the mounting bracket 20 from the inside. A substantially straight tubular base end 15 which is inserted into the inside of the mounting bracket 30 and has an enlarged diameter at the base end side of the tapered portion 13 is engaged with the mounting bracket 30 from the inside. Is formed.

The mounting brackets 20 and 30 have screw portions 2 for mounting the pipe spear to other members such as a coupling bracket and a water discharge nozzle.
1, 31 are formed. The connection structure such as the screw portion can be variously set according to the connection mode between the pipe spear and other members. For example, the connection structure may be a female screw different from the illustrated male screw, or a fitting type joint structure may be provided in accordance with the connection mode of the fitting or the water discharge nozzle attached to the fire hose.

Ring-shaped holding members 22 and 32 are screwed into the outer peripheral surfaces of the fittings 20 and 30 at the ends near the pipe 10, and the fittings 2 and 32 are used to attach the fittings 2 and 32.
Ring-shaped mounting members 23 and 33 inserted through the outer peripheral surface of the pipes 0 and 30 near the pipe 10 are held. The mounting members 23 and 33 are bent in a U-shape and
Attachment portions 23a and 33a are provided apart from the outer peripheral surface of 30. Both ends of a shoulder strap (not shown) are attached to attachment portions 23a and 33a.

The handle 40 includes a support band 41 attached so as to be wound around the pipe 10 in a semicircle, a support shaft 42 inserted through insertion holes 41 a formed at both ends of the support band 41, The holding member 43 includes a pair of side plate portions 43a attached to both end portions of the support shaft 42 and a holding shaft 43b connecting between the distal end portions of these side plate portions 43a. At one end of both ends of the support shaft 42, an enlarged diameter portion 42a having an increased outer diameter is provided, and a tightening nut 42b is screwed to the other end. The tightening nut 42b is configured to be easily rotatable with bare hands, and the degree of tightening of the tightening nut 42b can adjust the degree of tightening of the support strip 41 to the pipe 10 and rotate the gripping member 43, The angle with respect to the support strip 41 can be changed.

FIG. 3 is a schematic process diagram showing the outline of the manufacturing method of the above embodiment. As shown in FIG. 3 (a), a portion near one end of the straight tubular pipe 10 formed by plastic working or the like is expanded from the inside using a diameter expanding tool, or by pressing or swaging. As described above, the diameter of the pipe is gradually increased toward the end, and the diameter of the pipe is formed so as to be continuous and continuous with the end where the diameter of the taper 13 is increased. The base end 15 is formed by plastic working as shown in FIG. Next, as shown in FIG. 3C, the fittings 20 and 30 are inserted through the distal end portion 14 and the base end portion 15 of the pipe 10 formed as shown in FIG. The distal end portion 14 and the proximal end portion 15 are pushed out from the inside using a tool or the like, so that the distal end portion 14 and the proximal end portion 15 are fixed to the inner surfaces of the mounting brackets 20, 30.

FIG. 4 is an enlarged sectional view showing a state where the base end portion 15 is fixed to the mounting bracket 30. Ring-shaped annular grooves 30a, 30b are formed on the inner peripheral surface of the mounting bracket 30.
Are formed, and the proximal end portion 15 is expanded from the inside.
Are fixed so as to bite into these grooves 30a and 30b. A step 30c is formed on the inner peripheral surface of the mounting bracket 30, and the end 14a of the base end 15 is deformed along the surface of the step 30 so that the pipe diameter increases. Such a structure is similarly formed in the fixing structure of the distal end portion 14 and the mounting bracket 20. Thus, the pipe 10
Are fixed to the mounting brackets 20 and 30 in a crimped state from the inside with an uneven structure changed in the radial direction.

As shown in FIG. 3 (c), the pipe 10 having the fittings 20, 30 attached thereto as shown in FIG. 3 (c) has the fitting fitting 20, the straight pipe section 16, the tapered section 13, and the fitting fitting 30 in this order. The shape extends linearly from to the base end. Finally,
The curved portion 12 shown in FIGS. 1 and 2 is formed in a portion of the straight pipe portion 16 near the tapered portion 13 by plastic working using a bending tool or a bending machine. Portions of the straight pipe portion 16 other than the curved portion 12 are the same as those of the straight pipe portion 1 described above.
It becomes 1.

The bending angle θ of the bending portion 12 is 20 to 60
Degrees, preferably 30 to 50 degrees, and 45 degrees in the illustrated example.
Set to degree. The bending angle θ is appropriately set to an optimum angle for reducing blurring at the time of water discharge, or an angle that the user feels most preferable.

According to the present embodiment described above, since the pipe 10 is curved by plastic working, the pipe inner surface can be smoothly curved and the water transmission resistance can be reduced, and the main member is not a casting but a cast member. Since the pipe 10 formed by plastic working can be used, it is easy to form the pipe inner surface itself smoothly, and it is possible to further reduce the water transmission resistance.

Further, the end of the pipe 10 is connected to the mounting bracket 20,
Since it is fixed from the inside of the pipe 30, it can be configured without making a large step on the inner surface of the end of the pipe spear, so that the water transmission resistance can be reduced from this point as well.

Further, since the pipe spear is formed by plastic working using the pipe 10, it is possible to reduce the wall thickness while securing rigidity and strength required for the pipe spear such as pressure resistance, and to achieve a remarkable weight reduction. it can.

With respect to the above-described manufacturing process, the formation of the tapered portion and the mounting of the mounting bracket are first performed on the pipe 10, and then the formation of the curved portion is performed. In particular, when mounting the mounting brackets, the centering operation is facilitated, and the mounting of the two mounting brackets simultaneously is also facilitated.

In the present embodiment, as described above, in addition to reducing the weight of the pipe spear and reducing the water transmission resistance, a troublesome operation such as directly screwing a main body made of a casting is unnecessary. In addition, since the handleability is also improved, there is an effect that the manufacturing cost can be reduced.

[0033]

As described above, according to the present invention, since the pipe is provided with the curved portion, the water conduit can be formed smoothly and the inner surface of the pipe spear can be formed easily and smoothly. As a result, water conveyance resistance can be reduced, and furthermore, the weight can be easily reduced, so that the burden on the operator can be remarkably reduced as compared with the related art, and the manufacturing cost can be reduced as a whole.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a pipe spear according to the present invention.

FIG. 2 is a cross-sectional view of the same embodiment.

FIG. 3 is a schematic process diagram schematically showing the manufacturing method of the embodiment.

FIG. 4 is an enlarged partial cross-sectional view showing a structure of a fixing portion between the pipe and the mounting bracket of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Pipe 11 Straight pipe part 12 Curved part 13 Tapered part 14 Tip part 15 Base end part 20,30 Mounting bracket

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yasuaki Yamaguchi 3-14-4 Uchikanda, Chiyoda-ku, Tokyo Fukushima Fire Equipment Co., Ltd. F-term (reference) 2E189 LA02 4E087 HA47

Claims (9)

[Claims] An inlet diameter and an outlet diameter are configured to be different from each other by a tapered portion obtained by gradually changing a pipe diameter of a metal pipe, and a curved portion is formed in at least a part of the pipe. A pipe spear characterized by: 2. The pipe spear according to claim 1, wherein the curved portion is formed at a portion not overlapping the tapered portion. 3. The pipe spear according to claim 1, wherein an end of the pipe is fixed to an inner surface of a fitting. 4. The pipe spear according to claim 3, wherein the pipe and the fitting have a fixing structure in which the end of the pipe is enlarged in diameter inside the fitting. 5. A pipe spear characterized in that an end of a metal pipe is pushed out from the inside and fixed to an inner surface of a fitting. 6. The fixing structure according to claim 4, wherein the bonding structure between the end of the pipe and the inner surface of the mounting bracket has an uneven bonding surface having a bonding diameter that increases or decreases in the axial direction of the pipe. A pipe spear characterized by having. 7. A method for manufacturing a pipe spear, comprising forming a curved portion by bending a metal pipe by plastic working. 8. The method according to claim 7, wherein the curved portion is formed after forming a tapered portion having a gradually changing pipe diameter by plastic working on the pipe. 9. The method according to claim 7, wherein a fitting is attached to an end of the pipe before forming the curved portion.