JPH0224581Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is designed to connect pipes cut to a predetermined length with joints in the installation work of city gas, oil, etc. pipes. On the other hand, the present invention relates to a die head cheeser device for threading a tubular body with a guide adapter that can perform thread cutting quickly, easily, and accurately without failure by manual operation.

[Conventional technology] Conventionally, when laying pipes for city gas, high-pressure combustible gas, petroleum, etc., joints have been used to connect pipe bodies. There is a lot of work that requires tapered male threads.

An electric die-head chiaser device is known as a device that easily performs this thread cutting.
Since this device is large and heavy, it cannot be carried around manually, so generally a truck or the like with this device installed on a loading platform is brought into the work site and the cutting work is performed on the loading platform. However, depending on the work site, it may be difficult for trucks to enter, and since this device is electrically operated, it may not be suitable for safety reasons at work sites where there is a risk of flammable or explosive atmospheres. In some cases.

From this point of view, there is a need for a lightweight, simple, manual die head cheeser device, and a die head cheeser 1 (trade name: Rigid) is conventionally known, as shown in FIGS. 1A and 1B. This die-headed cheeser 1 includes a cheeser (comb bit) 2 having a plurality of chevron-shaped cutting edges 2a for cutting tapered male threads for pipes, and a total of four cheesers 2 fixedly held at every 90 degrees around the shaft center. and a holder 4 having a central hole 4a into which the tube body 3 is inserted,
This is a so-called radial die-headed cheeser. In thread cutting, the tubular body 3 is fixed with a tripod vise (not shown) or the like, and its opening is inserted into the center hole 4a of the die head chiaser 1, and the end 3a is aligned with the cutting edge 2a. Adjust the axial center of the die head cheeser 1 and the axial center of the tube body 3 so that they are aligned (centering), and press the die head cheeser 1 in the direction of arrow A with one hand. At the same time, by rotating a special tool (not shown) with the other hand in the direction of arrow B, which is engaged with a plurality of protrusions 4a surrounding the rear outer circumference of the holder 4 and formed at a constant angle, the pipe can be removed. A tapered external pipe thread is formed on the outer peripheral surface of the opening of the body 3 .

[Problems to be solved] However, the cutting edge 2a can be successfully moved to the end of the tube body 3 by pressing the cutting edge 2a in the direction of the arrow A with one hand and simultaneously rotating it in the direction of the arrow B with the other hand. It is difficult for even highly skilled people to attach the edges, and they often fail in this task and damage the edges. Therefore, tube body 3
In many cases, the pipe body 3 is cut to a predetermined size and then a new cutting operation is attempted, but if the cutting process fails two or three times, the tube body 3 cut to a predetermined size may end up being shorter than the allowable size. In some cases, it may no longer be possible to use it for that purpose.

In this die head cheeser 1, the diameter of the chevron-shaped cutting edge 2a of the cheeser 2 gradually increases as is clear from FIG. It is necessary to press the die head cheeser 1 as hard as possible in the direction of arrow A to prevent this from happening, and this force is based on experience. Even if this force is applied correctly in the direction of arrow A (direction of the axis), the rotational operation in the direction of arrow B will result in shifting the axis of the die head chiaser 1.

On the other hand, Utility Model Publication No. 10-16132 discloses a cylindrical fixed frame that guides a spiral pipe with a spiral cutting piece attached thereto as it rotates, and a cylindrical fixed frame with a cylindrical fixed frame that is radially directed toward the inner space at one end of the cylindrical fixed frame. A spiral cutter is disclosed which has a plurality of fastening screws and a rotary plate that engages with the fastening screws and moves them back and forth.

However, this spiral cutter has the following drawbacks.

A thread is formed on the outer periphery of the spiral tube, and a thread that is screwed into this thread is formed on the inner periphery of the cylindrical fixing frame, so the distance between the cylindrical fixing frame and the tubular body to be cut is quite large. It is large, and the cylindrical fixed frame is likely to rattle against the cut tube body, and the helical cutting piece has poor bite at the opening of the cut tube body.

In addition, by tightening with multiple tightening screws,
Since the cylindrical fixing frame is fixed to the tubular body to be cut, as mentioned above, the distance between the cylindrical fixing frame and the tubular body to be cut is quite large, making it difficult to stably fix the frame and the guiding function. Becomes unstable.

Furthermore, a rotating plate is required to move the plurality of fastening screws back and forth, and the overall number of parts is large and the structure is complicated.

The purpose of the present invention is to solve the above-mentioned drawbacks, and to provide a die-head cheeser device that can manually cut threads on the outer circumferential surface of the opening of a tube, quickly, easily, and accurately without failure. A tube body with a guide adapter that can be machined, and in particular, can reliably engage thread cutting, and can stably guide a die head chiaser in the tube axis direction, and is also simple in construction. The goal is to realize a die head cheeser device for threading.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the structure of the die head cheeser device for threading a tube body with a guide adapter according to the present invention is formed by combining the following die head cheeser and guide adapter.

A die-headed cheeser consists of a cheeser that performs thread cutting on the outer circumferential surface of a tube opening, and a holder that has a central hole into which the tube opening is inserted and holds the cheeser fixedly. .

The guide adapter has a second guide thread that is threaded into the first guide thread formed on the inner surface of the center hole of the holder.
It has a cylindrical guide member having a guiding thread formed on its outer circumferential surface, and a member that prevents the cylindrical guide member from rotating relative to the tubular body fitted into the cylindrical guide member. The anti-rotation member is
A tapered surface formed on the outer periphery of one end of the cylindrical guide member, at least three tapered holes bored in the tapered surface, a sphere floating in the tapered hole, and a second guide thread. and a spherical body feeding member which is screwed into the cylindrical guide member and fitted into one end of the cylindrical guide member to move the spherical body forward and backward in the axial center direction.

[Example] Next, an example of the present invention will be described based on the drawings.

FIG. 2A is a perspective view showing an embodiment of a die head cheeser device for threading a pipe body with a guide adapter according to the present invention.

FIG. 2B is an assembled perspective view of the same embodiment.

FIGS. 3A and 3B are partially vertical side views showing how the embodiment is used.

Note that in FIGS. 2 and 3, the same parts as those shown in FIG. 2 are given the same reference numerals, and their explanations will be omitted.

A die head cheeser device for threading a tube body with a guide adapter is roughly composed of a die head cheeser 10, a die head cheeser 1', and a guide adapter 20.
The die head cheeser 1' is an improvement of the conventional die head cheeser 1 shown in FIGS. 1A and 1B, and as is clear from FIG. A threaded portion 4c having a pitch P equal to the pitch P of the cutting edge 2a of the chaser 2 is formed on the cutting edge 2a of the chaser 2.

The adapter 20 includes a cylindrical guide member 25 and a pressing member 30. Cylindrical guide member 2
5 has an inner diameter slightly larger than the outer diameter of the tube body 3,
This inner diameter is approximately equal to the inner diameter of the positioning reduced diameter portion 4d of the holder 4 located in front of the chamfered portion of the chaser 2. On the other hand, the outer peripheral surface of the cylindrical guide member 25 is formed with a threaded portion having a pitch P that is threaded into the threaded portion 4c of the central hole 4a. A tapered surface 27 is formed on the outer peripheral surface of one end of the cylindrical guide member 25, and a tapered hole 27 is formed at every 120 degrees of the axial center of this tapered surface 27.
a, 27b, and 27c are bored. Steel balls 29a, 29b, and 29c are accommodated in each of the tapered holes 27a, 27b, and 27c so that a portion of their spherical surfaces face the through hole 28 of the cylindrical guide member 25.

The pressing member 30 has a substantially annular shape, and its outer peripheral surface is provided with twill knurling 31a for preventing slippage. A threaded portion 32 is formed on the inner surface of the pressing member 30 to be threaded into the threaded portion 26 of the cylindrical guide member 25, and the opening thereof has a taper that abuts against the tapered surface of the cylindrical guide member 25. An inner surface 33 is formed.

Next, the operation and usage of the above embodiment will be explained.

First, the tubular body 3 cut to a predetermined size is fixed in a vise or the like (not shown). Next, the pressing member 30 is slightly screwed onto the cylindrical guide member 25 and assembled, and the threaded portion 4c of the cylindrical guide member 25 and the threaded portion 4c of the die head chiaser 1' are screwed together to prevent wobbling between them. Unify into a state of non-existence. The assembled die head cheeser device 10 is fitted into the opening of the tube body 3, and the end portion 3a is inserted into the cutting edge 2a of the cheeser 2.
Make it come into contact with the chamfered part.

In the axial fitting operation of this device 10,
The inner diameter of the cylindrical guide member 25 is set to be slightly larger than the outer diameter of the tubular body 3, so that a gap 25a is formed, so that there is no binding between the two, and the guide member can be moved smoothly.

Next, the pressing member 30 is rotated and tightened by hand. This rotational operation causes the tapered inner surface 33 of the pressing member 30 to rotate through the three steel balls 29a, 29b, 29c.
are pressed simultaneously and with an even force to gradually extend a portion of these spherical surfaces toward the axial center, thereby tightening the tubular body 3 in three radial directions.As a result, the cylindrical guide member 25 is prevented from rotating relative to the tube body 3. In this way, the steel balls 29a,
29b, 29c and the pressing member 30 constitute a rotation preventing member. In this detent operation,
Since the steel balls 29a, 29b, and 29c are gradually displaced toward the axial center, the inevitable deviation between the axis of the guide member 25 and the axis of the tube body 3 due to the existence of the gap 25a is automatically corrected, and the tightening is completed. At times, both axes will coincide. This effect is particularly due to the fact that the steel balls 29a, 29b, 29c are arranged at intervals of 120 degrees from the center of the axis, and due to point contact by the rotation prevention member, the end 3a side of the tube body 3 is connected to the steel balls 29a, 29b, 29c. Spherical motion is promoted using 29c as a fulcrum, and centering of the opening side of the tube body 3 with respect to the chamfered portions of the cutting edges 2a of the plurality of chasers 2 is automatically achieved. Therefore, the device of this embodiment has the advantage that there is no need to perform any special alignment adjustment between the chaser 2 and the tube body 3.

Next, in the thread cutting operation, a plurality of protrusions 4
Rotate the die head chiaser 1' in the direction of arrow B in FIG. 3A by rotating a special tool (not shown) hooked to b with one hand. In the initial stage of biting, the thread has not yet been formed, so the cutting edge 2a is not guided by the thread itself, and a reaction force is generated in the escape direction at the same time as the die head chiaser 1' rotates. However, since the threaded part 4c of the die head cheeser 1' and the threaded part 26 of the cylindrical guide member 25 are in a threaded relationship, the rotation of the die head cheeser 1' in the direction of arrow A causes This will be guided along the guide member 25 and pushed in the direction of arrow C, and as a result, the biting process will be easily accomplished. In addition, since the pitch P of the cutting edge 2a and the pitch P of the threaded portions 4c and 26 are equal, the threaded pitch formed on the outer periphery of the opening of the tube body 3 is completely equal to the pitch P of the cutting edge 2a. Become.

Thereafter, by continuing to rotate the die head cheeser 1', a tapered external pipe thread is formed with high accuracy on the outer circumferential surface of the opening of the pipe body 3, and the end portion 3a is formed as shown in FIG. 3B. It is fed out and the cutting process is completed.

As described above, since the threaded part 4c is formed on the die head chiaser 1' and the guide adapter 20 is newly added, it is possible to quickly and easily perform thread cutting with one hand. ,
Since the cylindrical guide member 25 and the tubular body 3 are in close contact with each other, the tubular body 3 can be held without wobbling, and the thread cutting can be completed accurately without failure, which is an excellent effect. . Furthermore, in this embodiment, alignment adjustment of the tube body 3 is not necessary, and in addition,
The threaded portion 26 of the guide member 25 is used both for guiding the die head cheeser 1' and for shifting the pressing member 30, and the structure is simple and can be put to practical use.

In the above embodiment, since the cylindrical guide member 25 and the pressing member 30 are constructed separately, the pressing member 30 may fall off, but in order to improve this, a circumferential groove is provided at the end of the tapered surface 27. By forming and fitting the stop ring to this,
It is possible to prevent the pressing member 30 from coming off.

[Effects of the Invention] As explained above, the die head cheeser device for threading a tube body with a guide adapter according to the present invention has the following effects.

Due to the function of the guide adapter, it is possible to bite into the opening of the tube body without failure, and thread cutting by manual operation can be accomplished quickly and easily.

A first guide thread is formed on the inner surface of the center hole of the holder of the die head cheeser, and a second guide thread that is threadedly engaged with the thread is formed on the outer peripheral surface of the cylindrical guide member. Since the tubular body to be cut and the cylindrical guide member into which it is fitted are in a loose fit state with a slight gap, the tubular body is not likely to wobble when fixed, and thread cutting can be performed stably and Can be done accurately.

The anti-rotation member includes a tapered surface formed on the outer periphery of one end of the cylindrical guide member, at least three tapered holes bored in the tapered surface, a sphere floating in the tapered holes, and a second sphere. It consists of a sphere feeding member that is screwed into the guide thread and fitted onto one end of the cylindrical guide member to move the sphere forward and backward in the direction of the axial center.The rotation of the sphere feeding member causes the sphere to move toward the axis. Since it moves back and forth toward the center, alignment between the tubular body and the cylindrical guide member is automatically achieved, and thread cutting can be performed smoothly and accurately. In addition, since the sphere dispensing mechanism of the anti-rotation member moves forward and backward by pressure caused by the rotation of the sphere dispensing member, the mechanism configuration is simple, and in particular, the sphere dispensing member is
Since it is screwed into the guide thread of the
The guide thread of the die head chiaser is screwed into it, and this ball feeding member is also screwed into it.As a result, the number of parts is small, it is a handy and lightweight type, and it is easy to manufacture. We can provide cheap products.

[Brief explanation of the drawing]

FIG. 1A is a perspective view of a conventional die head cheeser. FIG. 1B is a partially longitudinal side view thereof. FIG. 2A is a perspective view showing an embodiment of a die head cheeser device for threading a pipe body with a guide adapter according to the present invention. FIG. 2B is an assembled perspective view of the same embodiment. FIGS. 3A and 3B are partially vertical side views showing how the embodiment is used. 1, 1...Die-head cheeser, 2...Cheeser, 2a...Chevron cutting edge, 3...Tube body, 3a...
End portion, 4...Holder, 4a...Central hole, 4b...
Convex strip, 4c...Guide thread part, 4d...Positioning diameter reducing part, 10...Die head cheeser device for threading a tubular body with guide adapter, 20...Guide adapter, 25...Cylindrical guide member , 26...Guide thread portion, 27...Tapered surface, 27a, 27b,
27c...Tapered hole, 28...Through hole, 29a,
29b, 29c... Steel ball, 30... Pressing member, 3
1...Outer peripheral surface, 31a...Twill knurling, 32
...Threaded portion, 33...Tapered inner surface.

Claims (1)

[Claims for Utility Model Registration] A chaser that cuts threads on the outer circumferential surface of a tube opening, and a holder that fixes and holds the chaser by having a central hole into which the tube opening is inserted. For a die head thiers, the holder has a cylindrical shape in which a first guide thread is formed on the inner surface of the center hole, and a second guide thread is formed on the outer peripheral surface to be screwed into the thread. A guide adapter is combined with a guide member and a member that prevents the cylindrical guide member from rotating with respect to the tubular body fitted into the guide member, and the anti-rotation member is attached to the outer periphery of one end of the cylindrical guide member. A tapered surface formed in the section, and at least three holes bored in this tapered surface.
a sphere that moves freely within the taper hole, and a sphere that is screwed into the second guide thread and fitted onto one end of the cylindrical guide member to move the sphere forward and backward in the axial center direction. 1. A die head cheeser device for threading a pipe body with a guide adapter, comprising a feeding member.