JPH0326401A - Cutting tool for plastic tube - Google Patents

Abstract

PURPOSE:To have depth of cut held at a fixed value and stable cut performed by pressing a cutter blade against a plastic tube with action of a spring, making the tube concerned held on the blade in cooperation with a holder, and making the blade tip to project out by a cutting amount from a sliding part. CONSTITUTION:A holder 31 is lowered, a cutter 23 is raised and a core 12 is pressed in a plastic tube 11 at the time of starting cut. Next, a main body 17 is turned around the plastic tube 11, and the blade tip 25 of the cutter 23 is advanced to a cut starting position. The above-mentioned blade tip 25 is pressed in by action of a spring 28, and further the main body 17 is pressed in until a sliding part 24 hits the surface of the plastic tube. Next, a slant part 33 of the holder 31 is attached to a supporting arm 22, besides raised, the plastic tube 11 is held in a rectangular member 32, and the plastic tube 11 is held on the same circumference in cooperation with the blade tip 25. The blade tip 25 is provided in protrusion by a cutting amount from the sliding part 24 and when a handle 20 is turned, the blade tip 25 is sent in axial direction of the tube by the pitch of screw 13 for every one turn, and the outer surface of the tube is cut by the cutting amount.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to -1- A cutting method used to cut the outer surface of plastic pipes in piping work using plastic pipes, which have recently begun to be used as sewerage and gas pipes. Regarding tool C.

In conventional piping work, the work of connecting pipes and closing the ends of pipes is done using various types of joints, such as T-joints, sokeno [・joints, king-rubo joints, twill joints, and cap joints]. However, in the case of plastic pipes, these joints and pipes are generally connected by heat fusion. Such heat fusion bonding has normally been carried out by heating and melting the surface of a plastic tube with a heater, inserting it into the joint, and pressing it to crimp it. 6. In addition, there are some that have heating wires buried inside so that heat fusion can be performed by energizing. In any case, in order to ensure that the fusion is performed properly and that the strength of the fusion is not impaired, it is necessary to remove dirt and foreign matter adhering to the outer surface of the plastic tube. For this purpose, the pipe surface is scraped in the axial direction using a woodworking plane or the like, or a rotary plane is fitted onto the plastic pipe and rotated.

Among these rotary planes, there are those in which feeding in the direction of the tube axis is performed by -f-motion, and those that use a screw and the screw is moved one bit per rotation.

In the case of using a wooden planer of the secondary method, which the invention seeks to solve, it is difficult to uniformly carve the blue surface, resulting in uncut parts and uneven cutting depth.
There are drawbacks such as the surface becoming rough after cutting. In addition, with conventional rotary planes, if the pipe is crushed and deformed, or if the outer surface of the pipe changes, the blade cannot follow the pipe surface, resulting in uncut edges or uneven cutting patterns. In addition, it could only be used for pipes of the same diameter, and it was necessary to prepare and use different cutting tools depending on the size of the pipe. .

In addition, when a feeding mechanism using a screw is used, there is an advantage that feeding can be done in a constant and consistent manner, but as shown in Fig. 6, the core is fixed by forcibly fitting into the blast tube. 1, a holder 3 screwed onto a screw shaft 2 protruding from the core L, and a cutter L attached to the tip of the holder.
With conventional tools made of
1. Also, in order to provide rigidity, wIl tends to be large. The first object of Atsushi's invention is to provide a cutting tool whose blade can follow the deforming surface of a pipe and cut with a constant depth of cut.

A second object of the present invention is to provide a cutting tool with a simple structure that can cut with a constant feed rate without leaving any uncut parts.

A third object of the present invention is to provide a cutting tool that can be applied to plastic pipes of different diameters.

The cutting tool to achieve the first objective consists of a holder that rotatably engages the glass tube at at least two points around the circumference, and a tube attached to the holder. A cassoter for cutting the outer surface, the casoter is urged by a spring to protrude radially inward, and holds the plastic tube together with the holder L2, and a sliding contact portion that makes sliding contact with the outer surface of the tube; It has a cutting edge that protrudes from the sliding contact portion by the amount of cutting allowance and is located on the circumference. The cutting tool for achieving the second purpose has a core that fits into the end of the plastic pipe and is fixed, and the entire crank-shape, and an arm that is fixed to a screw shaft that is screwed into the core. Alternatively, a main body screwed into a screw shaft fixed to the core, and a cutter for cutting the outer surface of the tube attached to the main body;
It consists of a holder that is attached to the main body and rotatably supports the tube. A cutting tool for achieving the third purpose is a holder that rotatably engages with a plastic tube at at least two locations in the circumferential direction, preferably on the same circumference. It consists of a cutter which is attached to the holder so that its position can be adjusted, and whose cutting edge moves forward and backward in the radial direction by the 11 joints at the attachment position, and which grips the brass tube together with the holder. Another cutting tool for achieving the third purpose is that the holder of the cutting tool for achieving the second purpose is attached to the main body so that its position can be adjusted, and the cutting edge can be adjusted in diameter by adjusting the attachment position. The arm is connected to the screw shaft so as to be movable in the radial direction. To connect movably in the radial direction, for example, a nut is fixed or screwed onto a screw shaft, and the nut is slidably fitted into a long groove formed in the radial direction of the arm. The tsuba is used to prevent it from slipping out. The holders of each of the above tools must be prevented from moving or tilting in a direction perpendicular to the axis of the plastic tube during cutting. Therefore, for one person B,
The plastic tube's movement in the X-axis and Y-axis directions, which are orthogonal to the tube axis, is restricted by the honoredder and cutter. In the other case B, the tube is pressed against the holder by the cutter during cutting, and each point receives a component of the cutting resistance. In cutting tools designed to achieve the primary purpose of action, during cutting, the cutter is pressed against the plastic tube by the action of a spring, and cooperates with the holder to grip the blastinok tube. The cutting edge reliably bites into the plastic tube until the sliding part touches the outer surface of the tube, and this state is maintained during cutting. The holder supports the plastic tube on the same circumference as the cutting edge, ensuring stable cutting.

In a cutting tool that achieves the second purpose, the cutting edge is reliably fed one pift of the screw shaft by rotating it around a plastic tube. In addition, the holder restricts the inclination of the tool, preventing the cutter from swinging up and down or forward during cutting. In a cutting tool to achieve the third purpose, by changing the mounting position of the cutter and moving the cutting edge forward and backward in the radial direction,
The diameter of the inscribed circle that touches the holder and the cutting edge changes. Embodiment The core 12 fixedly fitted to the end of the plastic pipe 1l has a stepped shape so that it can be applied to a small-diameter plastic pipe and a large-diameter plastic pipe, respectively. The screw shaft l3 is screwed into. screw shaft l3
A nut opening 6 having an H-shaped cross section and having flanges 15 on both sides of the square piece l4 is fixed to the protruding end of the square piece l4. The crank-shaped main body l7 is parallel to the screw shaft 13 by fitting the square piece l4 of the nut 16 into the elongated hole 19 formed in the arm 18, and the interval can be set arbitrarily. They are connected so that they can be changed. At one end, there is a vertical groove 2 in which a canter (to be described later) is fitted and attached to the front surface.
A support arm 22, to which a holder for supporting the tube l1 is attached to the rear side, is formed to protrude obliquely downward, and a handle 20 is attached to the upper side. The cutter 23 has the same width as the vertical groove 21, has a sliding contact portion 24 at the lower end that slides into plastic pipe l1, and a cutting edge 25 that protrudes from the sliding contact portion 24 by an amount corresponding to the cutting allowance, and has the vertical groove 2l.
It is supported in a vertically slidable manner by a stepped screw 27 that is fitted into the main body l7 through a long hole 26 and fixed to the main body l7.
It is always urged downward by a spring 28 housed in the vertical groove. The holder 31 is composed of a right-angled portion 32 bent at a right angle and an inclined portion 33 extending diagonally upward from the right-angled portion 32. The blasting/liquid pipe is held on the circumference, and the inclined part 33 of the latter is inserted into the support arm 22, and the set screw 34 adjustably fixes the cleaning pipe. There is. During cutting, remove the holder 31 or lower it sufficiently to lift the cutting edge of the cutter 23, and then remove the core 12.
In the figure, 36 is a rubber ring that fits into the outer circumferential groove 37 of the core 12. When the core l2 is pushed in, it presses against the inner circumferential surface of the tube, and the core l2 (It is designed to prevent rotation.) Next, rotate the main body 17 around the plastic tube 11 and cutter 2.
3. Advance the cutting edge to the cutting start position (it may be advanced before the core 12 is pushed in) and release the lift of the cutter 23. Then, the cutting edge of the cutter 23 is pushed into the plastic tube 11 by the action of the spring 28 and the main body 17 until the sliding portion 24 hits the outer surface of the tube. Next, support holder 31 1? ! 22, lift it up, hold the brass pipe 1L with the right angle part 32, fix it with the 2 setscrews 34 and 1 with the trowel. As described above, when the handle 20 is tightened and rotated after it has been sewn (7), the screw shaft l3 is rotated with each rotation.
The cutting edge is sent in the direction of the tube axis, and the outer surface of the tube is cut by the cutting allowance.

When cutting plastic tubes with different diameters, either the different diameter portions of the F 12 are pushed into the tube end, or the A 12 is replaced with one of a different diameter and pushed in.

Then, the mounting position of the holder 31 is changed, and the plastic tube is held and fixed.

When cutting pipes with different diameters, the rake angle may change slightly, but it is preferable to maintain the optimum rake angle. To do this, as shown in FIG.
．． If Yi, its slope y+/xl and slope part 3
It is best to make the slopes of 3 match. Although the above embodiment includes a core 12, another embodiment includes a support arm, a holder, and a cutter mounted on the support arm, and the main body, screw shaft, and core are omitted.
In the case of the above embodiment, the movement of the plastic tube is restrained from the inside and outside by the holder, cutter, and core, so that it does not move in a direction perpendicular to the tube axis. If the plastic tube is only supported by the cutter, there is a risk that the plastic tube will escape toward the sloped part during cutting. One way to overcome this problem is to have the vertical component of the cutting force pass through or to the right of the axis of the plastic tube, forcing the plastic tube against the right angle section. In other words, in Fig. 3, the X seat IIXI of the cutting edge is relative to the X seat 1xt of the blastinok tube axis C,
The purpose is to have the relationship xl:;xl. Fig. 4 shows the modified form, in which the right angle part of the above embodiment B is shaped as three acute angle parts, and when cutting, the pipe 40
is pushed into the acute angle part 39. Another method, as shown in FIG. 5, is to configure the holder 4l with a right-angled portion 42 and a rising portion 43 whose mounting position can be adjusted with respect to the portion 42.
The first step is to adjust the mounting position of the tube so that the tube 45 is held between the tubes. This rising portion 43 is preferably sloped so that the rake angle of the cutting edge remains unchanged. In order to prevent the rake angle of the cutting edge from changing, the cutter 44 may be attached to the rising portion 43 so that its position can be adjusted not only in the rising direction but also in a direction orthogonal thereto, as shown in the figure.

Effects of the Invention The present invention is constructed as described below, and provides the following effects. According to the cutting tool according to claim 1, since the cutter is biased radially inward by the action of the spring and cooperates with the holder to grip the plastic pipe on the same circumference, the cassoter can hold the plastic pipe on the same circumference. It follows the external surface well and can reliably perform stable cutting. Additionally, since the sliding part is pressed against the outer surface of the tube during cutting, it is possible to cut with a constant depth of cut. According to the cutting tool according to claim 2, it is possible to feed the cutting tool by a certain amount in the direction of the tube axis each time it rotates, and since the inclination with respect to the tube axis is regulated by the holder, there is no pre-cutting of the cutting edge and there is no uncut material. According to the cutting tool according to claim 3, which is capable of cutting the outer surface of the tube without causing any damage, plastic tubes having different diameters can be cut by adjusting the mounting position of the cutter.

According to the cutting tool according to the fourth aspect, plastic pipes having different diameters can be cut by adjusting the mounting position of the holder. According to the cutting tool of the fifth aspect, the main body can be connected to the screw shaft so that the interval can be adjusted by fitting the square piece of the nut provided on the screw shaft into the long groove of the arm. In the cutting tool according to claim 6, cutting can be performed reliably and stably. The holder according to claim 7 can restrict the movement of the plastic tube in a direction perpendicular to the tube axis during cutting. In the cutting tool according to the eighth aspect, since the plastic tube is pressed against the bent portion during cutting, the tube does not separate from the bent portion and does not escape.

According to the holder according to claim 9, by supporting the plastic tube from three sides, movement in a direction perpendicular to the tube axis can be restrained. In the cutting tool according to claim 10, plastic pipes having different diameters can be cut at an optimal rake angle at all times. In the holder according to claim 11, the slanted portion can further serve to restrain the movement of the plastic tube.

[Brief explanation of drawings]

Claims (1)

[Claims] (1) Consisting of a holder that rotatably engages a plastic tube at at least two points on the circumference, and a cutter attached to the holder for cutting the outer surface of the tube, the cutter is A sliding contact portion that is biased to protrude radially inward by a spring, grips the plastic tube together with the holder, and slides on the outer surface of the tube; Cutting tool for plastic pipes (2) having a core that fits into the end of the plastic pipe and is held in a fixed state, and a screw shaft that is crank-shaped as a whole and has an arm that is screwed into the core. It consists of a main body that is screwed onto a screw shaft that is fixed or fixed to the core, a cutter for cutting the outer surface of the tube that is attached to the main body, and a holder that is attached to the main body and rotatably supports the tube. Cutting tool for plastic tubes (3) consisting of a holder that rotatably engages the plastic tube at at least two locations in the circumferential direction, and a holder that is attached to the holder so that its position can be adjusted, and the cutting edge can be adjusted in diameter by adjusting the attachment position. A cutting tool for plastic tubes consisting of a cutter that moves forward and backward in the radial direction and grips the plastic tube together with the holder. 3. The plastic pipe cutting tool according to claim 2, wherein the arm is movably connected to the screw shaft in a radial direction. The plastic pipe cutting tool (7) holder according to claim 4, wherein the holder and the cutting edge engage the plastic pipe on the same circumference, the holder of the plastic pipe cutting tool (7) according to claim 3, which fits into the plastic pipe. A plastic pipe cutting tool (8) according to any one of claims 1 to 4, which has a bending part that bends at an angle and hugs the plastic pipe. The plastic pipe cutting tool (9) according to claim 7, wherein the holder has a rising part that cooperates with the bending part to clamp the plastic pipe. 2. The cutting tool (10) holder according to claim 1, wherein the cutting tool (10) holder is composed of a bent part that is bent at an appropriate angle and holds the plastic tube, and an inclined part that is parallel to a line connecting the corner of the part and the cutting edge of the cutter. 11. The plastic pipe cutting tool according to claim 10, wherein the mounting position of the inclined portion of the plastic pipe cutting tool (11) according to claim 3 is adjustable according to the pipe diameter.