JPH11170109A - Pipe cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the cutting preparation of a large diameter pipe by placing a pipe on a pipe dead weight support roller, so that the dead weight of the pipe acts on the lower end part of an arm through the pipe dead weight support roller to automatically close the arm from open position to close position against energizing force. SOLUTION: Arms 10, 12 are openable and closable by rotating around a fulcrum possessed under a pipe between a close position for clamping the pipe and an open position capable of receiving the pipe within a housing space from above by a first clamp roller 16 and a second clamp roller 18. The arms 10, 12 have energizing means 30 for energizing them to the open position and lower end parts, and when the dead weight of the pipe acts on the lower end parts, the arms 10, 12 are moved from the open position to the close position against the energizing force of the energizing means 30. Thus, cutting preparation of a relatively thick and heavy pipe can be easily performed, and tire pipe can be surely supported and precisely cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe support mechanism for supporting a pipe when cutting the pipe, and a pipe cutter for cutting the pipe, and more particularly to a pipe having a large diameter. The present invention relates to a pipe support mechanism and a pipe cutter suitable for cutting a pipe.

[0002]

2. Description of the Related Art Conventionally, a pipe cutter for cutting a pipe to an appropriate length as required has been known. For example, Japanese Utility Model Laid-Open No. 60-67810 discloses a pipe cutter for cutting a pipe by rotating the entire cutter relatively around the pipe. The pipe cutter is opposed to each other to form a pipe housing space therebetween, and a pair of left and right support arms capable of receiving a pipe into the pipe housing space from below by opening downward around the pivot at the upper end, A roller positioning mechanism provided at the lower end of each support arm and near the upper end of the support arm, the roller allowing relative rotation around a pipe, and an arm opening and closing mechanism for manually opening and closing the arm; A cutter provided adjacent to the support mechanism; When cutting the pipe with the pipe cutter, the operator lifts the pipe, puts it into the pipe housing space from below the support arm, and while holding the pipe at this position, the operator manually operates the arm opening / closing mechanism. Operate to close the support arm and let the roller clamp the pipe.
Thus, the cutter is positioned with respect to the pipe, and the load of the cutter is supported by the pipe. Next, the roller that clamps the pipe is rolled on the outer peripheral surface of the pipe, and the pipe cutter is rotated around the pipe to cut the peripheral wall of the pipe.

[0003] Japanese Utility Model Application Laid-Open No. 64-34134 discloses that
A work support for a work to be cut is disclosed. The work support has an upwardly facing V-shaped work receiving area, extends longitudinally over the length of the work support, and is formed by a plurality of rollers arranged in parallel with each other to form a work receiving area. An inclined surface is formed.
The work is placed on the rollers of this work support base, and the pipe is rotated on the rollers by hand while pressing the rotating cutter provided at the end of the work support base against the peripheral wall of the pipe. Cut around.

[0004]

However, in the above-mentioned pipe cutter, when the pipe is clamped by the positioning mechanism of the cutter, an operator lifts the pipe and puts it into the pipe accommodating space from below the support arm, and inserts the pipe. With the support in this position, the operator must manually operate the arm opening / closing mechanism to close the support arm. Therefore, if the pipe is relatively thick and heavy, multiple workers must keep holding the pipe until it is clamped by the rollers. In the work support, the pipe is placed on the work support.Therefore, although there is no problem as described above, during the cutting operation by the cutter provided at the end of the work support, You must work while pushing the pipe down by hand.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pipe support which can easily prepare a relatively thick and heavy pipe for cutting, and which can securely support the pipe to perform a pipe cutting operation accurately. A mechanism and a pipe cutter are provided.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a first clamp roller, a second clamp roller, and a pipe weight support roller which are provided at a distance from each other around a space for accommodating a pipe to be cut. The pipe own weight support roller is provided below the pipe to support the weight of the pipe, and each of the first clamp roller and the second clamp roller forms a space for accommodating the pipe therebetween. Is provided on the two arms provided so as to face each other,
The arm is disposed below the pipe between a closed position in which the pipe is clamped by the first clamp roller and the second clamp roller, and an open position in which the pipe can be received in the housing space from above. Is provided so as to be openable and closable by rotating about a fulcrum provided at the center, and further has an urging means for urging the arm to the open position. The first clamp roller or the second clamp roller has a lower end that extends on a side opposite to the side on which the first clamp roller or the second clamp roller is provided, and the lower end and the pipe's own weight support roller are connected to the pipe's own weight support roller. The weights of the pipes are connected to each other so as to act on the lower end portion, whereby when the weights of the pipes act on the lower end portion, the arm is acted upon by the urging force of the urging means. It can be achieved by a pipe support mechanism for moving the closed position from the open position to.

In the present invention, since the arms are open upward, for example, the pipes can be inserted into the pipe housing space from above using a crane or the like. When the pipe is placed on the pipe's own weight support roller by a crane or the like, the pipe's own weight acts on the lower end of the arm via the pipe's own weight support roller, and the arm opens against the urging force of the urging means. Since the position is automatically closed from the position to the closing position, cutting preparation work is easy. In addition, since the pipe is securely clamped by the first clamp roller and the second clamp roller, the pipe can be cut accurately. Further, the object of the present invention is to provide a pipe having a first clamp roller, a second clamp roller and a pipe self-weight supporting roller provided at an interval around a housing space of a pipe to be cut, and A roller is provided below the pipe to support the weight of the pipe, and the first clamp roller and the second clamp roller are provided to face each other so as to form an accommodation space for the pipe therebetween. A closed position where the first clamp roller and the second clamp roller clamp the pipe, and an open position where the pipe can be received from above into the housing space. The arm is pivotally mounted about a fulcrum provided below the pipe so that the arm can be opened and closed. A biasing means for, also, each arm has a lower end portion extending on the side opposite to the side where the first clamping roller and the second clamping roller is provided with respect to the fulcrum,
The lower end and the pipe's own weight support roller are connected to each other such that the pipe's own weight received by the pipe's own weight support roller acts on the lower end, whereby the weight of the pipe acts on the lower end. When the arm has a pipe support mechanism that moves from the open position to the closed position against the urging force of the urging means, and furthermore, a cutting action point on a peripheral wall of the pipe is a cross-section of the pipe. Has a cutter mechanism having a rotary blade provided at a position above the horizontal center axis, and the cutter mechanism moves away from the peripheral wall of the pipe with respect to one of the arms so as not to hinder reception of the pipe. This can be achieved by a pipe cutter that is rotatably pivoted between a retracted position and a cutting position where the rotary blade abuts the peripheral wall of the pipe. According to the present invention, since the cutting action point of the peripheral wall of the pipe has the rotary blade provided at a position higher than the horizontal center axis in the cross section of the pipe, the operator can easily press the rotary blade downward to easily cut the pipe. Cutting work can be performed. Moreover, when the pipe is received in the pipe housing space, the cutter mechanism provided above the horizontal center axis in the cross section of the pipe and provided so as to cover the pipe is pivoted to a retracted position away from the peripheral wall of the pipe. So that the acceptance of pipes is not hindered.

[0008]

According to an embodiment of the present invention, when the arm is at the closed position, the engagement between the first clamp roller and the second clamp roller with the peripheral wall surface of the pipe is further improved. There is a clamp roller position adjusting mechanism for adjusting the position so as to be located above the horizontal center axis in the cross section of the pipe. Therefore, the engaging position between the first clamp roller and the second clamp roller and the peripheral wall surface of the pipe is set to be always higher than the horizontal center axis in the cross section of the pipe in accordance with the diameter of the pipe to be cut. Since the pipes having different diameters can be adjusted, the pipes having different diameters can be pressed downward by the first clamp roller and the second clamp roller to be surely clamped.

According to an embodiment of the present invention, the rotary blade further includes a chamfering cutter having an inclined cutter surface extending obliquely with respect to a peripheral wall edge of a cutting surface of the pipe and abutting against the peripheral wall edge. Further, the first clamp roller, the second clamp roller, and the pipe's own weight support roller are made of a high friction material so as to prevent the pipe from moving in the axial direction due to the contact of the inclined cutter surface.
Therefore, the movement of the pipe in the axial direction due to the axial force given to the pipe by the contact of the chamfering cutter surface is restricted, and the chamfering operation can be performed accurately.

[0010]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an end view of a pipe cutter having a pipe support mechanism according to the first embodiment, showing an open position of an arm before a pipe to be cut is placed. FIG. 2 shows the pipe cutter shown in FIG.
It is a side view of the pipe cutter seen in the direction of -II. FIG.
Has a pipe support mechanism 4 for clamping a pipe P to be cut, which is placed in the longitudinal direction, and a cutter mechanism 6 for cutting the pipe P. The pipe support mechanism 4 has a base 14 having two plates 8 provided at both ends thereof, and in an end view shown in FIG. 1, extends upward facing each other and a space for accommodating the pipe P therebetween. First arm 1 forming S
0 and a second arm 12. As can be seen from FIG. 2, the first arm 10 is provided on each of the plates 8 at both ends of the base 14, and the second arm 12 is provided only at substantially the center of the base 14 in the longitudinal direction. Have been.

In the end view shown in FIG. 1, the first arm 10 surrounds the pipe P so as to surround the accommodation space S of the pipe P.
From below the accommodation space S of FIG.
First inclined portion 1 extending outwardly and obliquely upward from X
0a, and a bent portion 10b rising substantially vertically from the outer end of the first inclined portion 10a. At the upper end of the rising portion 10b, a first clamp roller 16 made of rubber, which is in contact with the pipe P, is provided. Similarly to the first arm 10, the second arm 12 extends laterally outward from the vertical center axis XX below the housing space S of the pipe P so as to surround the housing space S of the pipe P. A lateral portion 12a extending in a direction opposite to the one arm 10, and a second inclined portion 12b extending obliquely upward from the outer end of the lateral portion 12a at an angle α of 45 ° in a direction away from the vertical axis XX. And a bent shape having: A slot 12c is formed in the second inclined portion 12b along the central axis in the longitudinal direction. The second inclined portion 12b is provided with a vertical roller support member 12d which extends vertically and has a rubber-made second clamp roller 18 provided at the upper end thereof.
2e. Vertical roller support member 12
A notch 12f is formed in d to engage with the upper edge surface of the second inclined portion 12b of the second arm 12 and slide. By loosening the screw 12e and sliding the notch 12f of the vertical roller supporting member 12d while being guided by the upper edge surface of the second inclined portion 12b, the vertical roller supporting member 12
d can be maintained in the vertical direction, and the vertical roller support member 12d can be translated. Also,
When the second clamp roller 18 is in the closed position and a push-back force is applied to the second clamp roller 18 by the pipe P, the notch 12f is opposed to the upper edge surface of the second inclined portion 12b, Screw 12 of support member 12d
prevents rotation about the part fixed by e,
Clamp the pipe P securely.

Since the slot 12c extends obliquely upward along the second inclined portion 12b in a direction away from the vertical center axis XX, the screw 12e is loosened and the vertical roller support member 12d is moved along the slot 12c. When moving in the direction of approaching or moving away from the pipe P, the length of the portion of the second arm 12 from the vertical center axis XX to the second clamp roller 18 depends on the diameter of the pipe P to be cut. And the second inclined portion 12 can be extended.
The second clamp roller 18 can be moved up and down along the line b. Therefore, the position of the second clamp roller 18 can always be positioned above the horizontal center axis ZZ (see FIG. 3) of the pipe P even when cutting a pipe P of any diameter. Thus, the pipe P can be pressed obliquely downward by the second clamp roller 18 and securely clamped. After the vertical roller supporting member 12d is moved to a predetermined position, the screw 12e is tightened and fixed. In this embodiment, the outer diameter is 15c.
m, 20 cm, 25 cm, 30 cm, 35 cm, and 40 cm.
Scales (not shown) indicating the positions of the vertical roller support members 12d corresponding to the respective outer diameters of the pipes P are marked on the inclined portion 12b in the longitudinal direction.

As shown by a dotted line in FIG. 1, each plate 8 has a long hole 20 formed therein. The pipe support mechanism 4 further has a horizontal bar 22 extending through the slot 20 from one plate 8 to the other plate 8 as shown in FIG. It is provided movably in the vertical direction. Horizontal bar 2 outside plate 8
2, a rubber pipe own weight support roller 24 is rotatably attached to each end. The proximal end of the lateral portion 12a of the second arm 12 is pivotally connected to a horizontal bar 22. 1, a U-shaped bar member 26 extending from one plate 8 to the other plate 8 is attached to the plate 8 on the second arm 12 side. The second arm 12 is seated on the upper end surface of the U-shaped bar member 26 near the boundary between the lateral portion 12a and the second inclined portion 12b.
6 can swing about the upper end face. 1st arm 1
The lower edge surface of the first first inclined portion 10a is seated on a fulcrum 28 provided on the outer surface of the plate 8, and is supported so as to be swingable about the fulcrum 28.

The first inclined portion 10 of the first arm 10
At the upper edge of a, a plurality of semicircular notches 10c, six in this embodiment, diagonally along the first inclined portion 10a,
They are arranged at a predetermined interval from each other. Each semicircular notch 10 c is formed in a size and shape that opens upward and fits with the horizontal bar 22.
Are received and engaged in one of the semicircular notches 10c. The semicircular notch 10c allows the second arm 12
Like the second clamp roller 18 provided in the first embodiment, the length of the portion from the vertical center axis XX of the first arm 10 to the first clamp roller 16 is extended according to the outer diameter of the pipe P to be cut. And the first arm 10
The position of the first clamp roller 16 provided at the upper end of
Horizontal center axis ZZ in the cross section of the pipe P to be cut
The vertical position of the first clamp roller 16 can be changed so as to be located above (see FIG. 3). This embodiment assumes that the pipes P having six different outer diameters are cut as described above. Therefore, the positions of the six semicircular notches 10c are determined by the vertical center axis XX in FIG. From the upper position to the inner position with respect to the vertical axis XX and toward the lower position, corresponding to the outer diameter of each pipe. For example, 15
cm pipe P, the first clamp roller 1
1, the semicircular notch 10c 'at the outermost and upper position in FIG. 1 is engaged with the horizontal bar 22. As a result, the position of the first clamp roller 16 is positioned close to the vertical center axis XX and at a low position, and the smallest 15 cm pipe P is slanted downward from a position above the horizontal center axis ZZ. Can be clamped. On the other hand, when cutting the thickest 40 cm pipe P, in order to raise the position of the first clamp roller 16, the innermost and lower semicircular notch 1 in FIG.
0c '' is engaged with the horizontal bar 22. Thereby, the first
The position of the clamp roller 16 is far from the vertical axis XX,
Further, the pipe P positioned at a high position and having a length of 40 cm can be clamped obliquely downward from a position above the horizontal center axis ZZ.

In order to change the position of the semicircular notch 10c, the first arm 10 is rotated counterclockwise in FIG.
Is rotated in a direction away from the horizontal bar 22, and when the semicircular notch 10 c is disengaged from the horizontal bar 22, the first arm 10 is slid obliquely on the fulcrum 28 to obtain a desired semicircular shape. Move the notch 10c to the position of the horizontal bar 22,
It is engaged with the horizontal bar 22. Further, a lower end 10 a ′ of the first inclined portion 10 a of each first arm 10, which extends in a direction opposite to the end provided with the first clamp roller 16 with respect to the fulcrum 28, is It is urged upward by the compression coil spring 30 provided on the outer surface, and the engagement between the horizontal bar 22 and the semicircular notch 10c is ensured. When the lower end 10a 'is urged upward, the first arm 10 is urged to the open position, and the horizontal bar 22 is elongated by the lower end 10a'.
And the second arm 12 connected to the horizontal bar 22 is also urged to the open position.

The compression coil spring 30 includes a loop-shaped base portion 30a wound around a first pin 32 provided on the outer surface of the plate 8, and two linear portions 30b extending in a V-shape from the base portion 30a. And The tip of one straight portion 30b is connected to a second pin 34 provided on the outer surface of the plate 8.
And the rotation of the compression coil spring 30 is prevented. The end of the other straight portion 30b is bent away from the first arm 10 so that friction between the straight portion 30b and the lower surface of the first inclined portion 10a is reduced. It contacts the lower surface and urges the first arm 10 upward to the open position. Further, as best shown in FIG. 1, the pipe cutter 2 has a cutter mechanism 6 provided on the outer surface of one first arm 10. The cutter mechanism 6 is pivotally attached to a rotating blade 36 for cutting the pipe P and an outer surface of the first arm 10, and
The rotary blade support portion 38 for supporting the rotary blade 36, a safety cover 40 pivotally mounted on the rotary blade support portion 38 for surrounding the periphery of the rotary blade 36, and the rotary blade support portion 38. A motor 42 (see FIG. 6) for driving the rotary blade 36 to rotate, an operation handle 44 extending upward from the rotary blade support 38, and provided on the operation handle 44 while the operator holds the hand. , An operation switch 46 for driving the rotary blade 36. The rotating blade 36, as described later,
Cutting cutter 36a for cutting pipe P into two
And a chamfering cutter 36b provided coaxially with the cutting cutter 36a. The safety cover 40 includes the spring 5
By 0, it is urged in a direction to cover the rotary blade 36.
The cutter mechanism 6 can swing about a pivot point between an operating position where the rotary blade 36 contacts the peripheral wall surface of the pipe P and a retracted position that does not hinder reception of the pipe P into the housing space S. .

FIGS. 3 to 6 are views showing a process in which the pipe P is received in the accommodation space S of the pipe P of the pipe cutter 2 and the rotary blade 36 cuts the pipe P.
The operation of the pipe cutter 2 will be described below with reference to FIGS. First, a predetermined semicircular notch 10c of the first arm 10 is engaged with the horizontal bar 22 according to the outer diameter of the pipe P to be cut, and the vertical roller support member 12d of the second arm 12 is Position and fix at the scale position. Then, lift the pipe P with a crane or the like,
From above, the first arm 10 and the second arm 12 shown in FIG.
And is placed on the pipe's own weight support roller 24 as shown in FIG. Due to the weight of the pipe P, the pipe's own weight support roller 24 is pushed down, and the horizontal bar 22
The arm 10 moves to the lower end of the elongated hole 20 against the urging force of the compression coil spring 30 that urges the arm 10 upward. At this time, the first arm 10 moves in a direction of approaching each other around the fulcrum 28 and the second arm 12 around the upper end surface of the U-shaped bar member 26, that is, from the open position to the closed position. Moving. The first arm 10 is connected to the fulcrum 28 and the compression coil spring 30 and the second arm 12
Are seated on the upper end surface of the U-shaped bar member 26, so that they can relatively slide and move, and as the horizontal bar 22 moves to the lower end of the elongated hole 20, the first arm 10 and the The two arms 12 slide and move slightly away from the horizontal bar 22. The first clamp roller 16 and the second clamp roller 18 engage the outer peripheral surface of the pipe P to clamp the pipe P. At this time, the cutter mechanism 6 is at the retracted position.

The first arm 10 and the second arm 12
Is in the closed position, the first clamp roller 16 and the second clamp roller 18 form an angle β and an angle γ, respectively, upward with respect to the horizontal center axis ZZ of the cross section of the pipe P. That is, the first clamp roller 16 and the second clamp roller 18 are located above the horizontal center axis Z-Z of the cross section of the pipe P, and press the pipe P downward to securely clamp the pipe P. I have. FIG.
The operator grips the operating handle 44 of the cutter mechanism 6, rotates the cutter mechanism 6 about the pivot point 48, moves the rotary blade 36 toward the pipe P, and the rotary blade 36 Shows a state in which it is in contact with. Note that the safety cover 40 is located at a position substantially in contact with the peripheral surface of the pipe P.

FIG. 5 is a diagram showing the pipe P being cut by the rotary blade 36, and FIG. 6 is an end view opposite to FIG. Subsequently, the operator operates the operation handle 4
The user operates the operation switch 46 provided at the position 4. This allows
The rotary blade 36 is driven to rotate by the motor 42, and while the operator holds the operation switch 46, the operating handle 44
Is pressed against the outer peripheral surface of the pipe P, the peripheral wall of the pipe P is cut by the rotary blade 36 as shown in FIG. As the peripheral wall of the pipe P is cut by the rotary blade 36, the safety cover 40 is pushed back radially outward of the pipe P by the peripheral surface of the pipe P against the urging force of the spring 50, and the rotary blade support portion. 38. While cutting, the pipe P is rotated in the direction of any of the arrows shown in FIG. 5 about the longitudinal axis with the other hand not holding the operation switch 46. When the entire periphery of the peripheral wall of the pipe P is cut by the rotary blade 36, the pipe P is separated into two parts.

FIG. 7 is a schematic diagram showing the relationship between the rotary blade 36 and the pipe P. The rotary blade 36 has a cutting cutter 36a for cutting the pipe P into two, and a chamfering cutter 36b coaxially arranged with the rotary cutting cutter 36a. The chamfering cutter 36b has an inclined cutter surface 36c extending obliquely from the inside to the outside in the radial direction of the pipe P with respect to the cut surface of the pipe P on the outer periphery. For chamfering by pressing against the outer peripheral edge of the. The chamfering is performed, for example, in a case where the cut pipe P is used by inserting it into another tubular member, in order to make the shape easier to insert. As described above, when the operator holds the handle 44 of the cutter mechanism 6 and presses the cutting cutter 36a against the peripheral wall of the pipe P, the pipe P is cut by the cutting cutter 36a. Pipe P by cutting cutter 36a
, The inclined cutter surface 36c of the chamfering cutter 36b is pressed against the outer peripheral edge of the cut surface of the pipe P to be chamfered. When the inclined cutter surface 36c is pressed against the outer peripheral edge of the cut surface of the pipe P, the pipe P to be chamfered is moved by applying an axial force thereto, so that the chamfering operation cannot be performed accurately. Although there is a possibility that the first clamp roller 16, the second clamp roller 18, and the pipe's own weight support roller 24 are made of rubber, the movement of the pipe P in the axial direction is restricted by the frictional force with the pipe P. You.

FIG. 8 is a view similar to FIG. 1, showing a second embodiment. The pipe cutter shown in FIG. 8 is a second arm 1 of the pipe cutter 2 according to the first embodiment shown in FIG.
In this embodiment, a plurality of semicircular notches 12g are provided at the lower edge of the slot 12c formed in the second arm 12 shown in FIG. Have the same configuration as the pipe cutter 2 shown in FIG. 1 except that they are formed at predetermined intervals. Therefore, for the same parts as in FIG.
The same reference numerals as in FIG. 1 are used. 12g each semicircular notch
Is formed in a size and shape that opens upward and fits with the screw 12e. 6 semicircular notches 12
g is paired with six semicircular notches 10c formed in the first arm 10 from the side closer to the vertical center axis XX toward the side farther from the vertical center axis XX, and each pair is cut. It corresponds to six different outer diameter pipes P. The vertical roller support member 12d is moved along the slot 12c, and the screw 12e is fitted and fixed in one of the semicircular notches 12g corresponding to the outer diameter of the pipe P to be cut.

According to the first embodiment and the second embodiment,
A safety cover 40 is pivotally attached to the rotary blade support 38, and
Since the spring 50 urges the rotary blade 36 in a direction to cover the rotary blade 36, the rotary blade 3
6 is always surrounded by the safety cover 40, and the safety of the worker is ensured. Furthermore, the safety cover 4
0 is pushed back radially outward of the pipe P by the peripheral surface of the pipe P against the urging force of the spring 50 as the peripheral wall of the pipe P is cut by the rotary blade 36.
There is no hindrance to the cutting operation by the rotary blade 36. According to the first and second embodiments, the notch 12f is formed in the vertical roller support member 12d, so that the notch 12f of the vertical roller support member 12d is Guided by the upper edge surface, the vertical roller support member 12d can be translated obliquely up and down while maintaining the vertical direction. Further, when the second clamp roller 18 is in the closed position, when the pipe P applies a pushing back force to the second clamp roller 18, the notch 12 f resists the upper edge surface of the second inclined portion 12 b. , Screw 1 of vertical roller support member 12d
Rotation around the fixed portion is prevented by 2e, and the pipe P can be held securely.

According to the second embodiment shown in FIG. 8, by providing the semicircular notch 12g, the vertical roller supporting member 12d can be accurately positioned at a predetermined distance from the vertical center axis XX. In addition to being able to position easily, when the pipe P is clamped by the second clamp roller 18, it is possible to prevent the screw 12e at the support point at the base end of the vertical roller support member 12d from shifting. The present invention
Without being limited to the above embodiments, various modifications are possible within the scope of the invention described in the claims, and it is needless to say that they are also included in the scope of the invention. Nor. For example, the first and second embodiments
As in the first clamp roller 16 and the second clamping roller 18 is preferably located above the horizontal center axis in the cross section of the pipe P to be cut,
As long as the pipe P can be clamped in the horizontal direction, it may be arranged on the horizontal central axis.

The position of the semicircular notch 10c in the first and second embodiments and the semicircular notch 12g in the second embodiment depend on the size of the pipe P to be cut. The number can be changed according to the number of types of pipes P to be cut, and the size and shape can be changed according to the thickness and cross-sectional shape of the horizontal bar 22. Further, the pipe support mechanism 4 in the first embodiment and the second embodiment is further provided on the opposite side of the cutter mechanism 6, that is, on the left side in FIG. 2, and on both sides of the cutter mechanism 6. The pipe P may be supported. With this configuration, not only can the pipe P be clamped more securely, but also the two cut pipes P are held on the pipe support device after cutting, and do not fall.

Further, in the pipe cutters 2 and 50 in the first embodiment and the second embodiment, the first arm 1
A compression coil spring 30 is provided to urge 0 upward toward the open position. However, the first arm 10,
The center of gravity of the first clamp roller 16 and the entire cutter mechanism 30 supported thereby is positioned with respect to the fulcrum 28.
In the case where the first arm 10 is located farther from the vertical center axis XX, the compression coil spring 30 may be omitted, and the first arm 10 may be maintained in the open position around the fulcrum 28 by their own weight. Good.

[0026]

According to the present invention, preparation for cutting a relatively thick and heavy pipe can be easily performed, and moreover, the pipe can be securely supported and a pipe cutting operation can be accurately performed. A pipe support mechanism and a pipe cutter can be provided.

[Brief description of the drawings]

FIG. 1 is an end view of a pipe cutter having a pipe support mechanism according to an embodiment, showing an open position of an arm before a pipe to be cut is placed.

FIG. 2 is a side view of the pipe cutter shown in FIG. 1 as viewed in the direction of II-II.

FIG. 3 is a view showing a process in which a pipe is received in a pipe storage space of a pipe cutter and the pipe is cut by a rotary blade.

FIG. 4 is a view similar to FIG. 3;

FIG. 5 is a view similar to FIG. 3;

FIG. 6 is a view similar to FIG. 3;

FIG. 7 is a schematic diagram showing a relationship between a rotary blade and a pipe.

FIG. 8 is a view similar to FIG. 1, showing a second embodiment.

[Explanation of symbols]

 Reference Signs List 2 pipe cutter 4 pipe support mechanism 6 cutter mechanism 10 first arm 10a first inclined portion 10b rising portion 10c semicircular notch 12 second arm 12a lateral portion 12b second inclined portion 12d vertical member 12g semicircular notch 16 First clamp roller 18 Second clamp roller 24 Pipe's own weight support roller 36 Rotating blade 36a Cutting cutter 36b Chamfering cutter

Claims (4)

[Claims] A first clamp roller and a second clamp roller provided at a distance from each other around an accommodation space of a pipe to be cut;
A clamp roller and a pipe weight support roller are provided below the pipe to support the weight of the pipe. Each of the first clamp roller and the second clamp roller is Provided in two arms provided to face each other so as to form an accommodation space for the pipe, the arm is a closed position for clamping the pipe by the first clamp roller and the second clamp roller, The pipe is provided so as to be openable and closable by pivoting about a fulcrum provided below the pipe between an open position where the pipe can be received in the accommodation space from above, and the arm is opened. The arm has an urging means for urging the arm, and each of the arms has the first clamp roller or the second clamp roller with respect to the fulcrum. It has a lower end that extends on the opposite side to the side provided, and the lower end and the pipe's own weight support roller are separated from each other such that the weight of the pipe received by the pipe's own weight support roller acts on the lower end. A pipe support mechanism, wherein the arm moves from the open position to the closed position against the urging force of the urging means when the weight of the pipe acts on the lower end portion. 2. When the arm is at the closed position, an engagement portion between the first clamp roller and the second clamp roller with a peripheral wall surface of the pipe is positioned at a horizontal center axis in a cross section of the pipe. The pipe support mechanism according to claim 1, further comprising a clamp roller position adjusting mechanism for adjusting the position of the clamp roller so as to be positioned above. 3. A first clamp roller and a second clamp roller, which are provided at intervals around a housing space of a pipe to be cut.
A clamp roller and a pipe weight support roller are provided below the pipe to support the weight of the pipe. Each of the first clamp roller and the second clamp roller is Provided in two arms provided to face each other so as to form an accommodation space for the pipe, the arm is a closed position for clamping the pipe by the first clamp roller and the second clamp roller, The pipe is provided so as to be openable and closable by pivoting about a fulcrum provided below the pipe between an open position where the pipe can be received in the accommodation space from above, and the arm is opened. The arm has an urging means for urging the arm, and each of the arms has the first clamp roller or the second clamp roller with respect to the fulcrum. It has a lower end that extends on the opposite side to the side provided, and the lower end and the pipe's own weight support roller are separated from each other such that the weight of the pipe received by the pipe's own weight support roller acts on the lower end. Connected, whereby, when the weight of the pipe acts on the lower end, the arm has a pipe support mechanism that moves from the open position to the closed position against the urging force of the urging means, Further, the cutting action point on the peripheral wall of the pipe has a cutter mechanism having a rotary blade provided above the horizontal center axis in the cross section of the pipe, and the cutter mechanism does not prevent the pipe from being received. The rotary blade is rotatably connected to one of the arms between a retracted position away from the peripheral wall of the pipe and a cutting position where the rotary blade abuts on the peripheral wall of the pipe. Ip cutter. 4. The rotary blade further includes a chamfering cutter having an inclined cutter surface that extends obliquely with respect to a peripheral wall edge of a cutting surface of the pipe and abuts against the peripheral wall edge. The said 2nd clamp roller and the said pipe self-weight support roller are made of a high friction material so that the axial movement of the said pipe may be prevented by the contact of the said inclined cutter surface.
A pipe cutter as described in 1.