DE8126783U1 - "PIPE CUTTER, ESPECIALLY FOR PLASTIC PIPES" - Google Patents

Description

108/75 _ VNR: 110086 -3-

Company

ROTHENBERGER GmbH & Co

Tools-Machines KG

Heidelberger Strasse 13
6000 Frankfurt am Main-1

"Pipe cutter, especially for plastic pipes."

The innovation concerns a pipe cutter, ins- | special for plastic pipes, consisting of a ί

line the pipe with a housing that can be guided around the |

Rotating tube attacking guide for the housing | and a parting tool adjustable in the radial direction to the axis of rotation by means of a spindle ¹ and a longitudinal guide, in which the longitudinal guide consists of a recess arranged radially in the housing and a tool holder displaceable in the recess and in which the parting tool has a cutting edge , which runs at an angle different from zero degrees and 90 degrees to the direction of displacement of the tool holder and is in the "essential ichen" in a plane laid through the axis of rotation, in such a way that the cutting

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edge chamfers can be produced in the area of the cut edge of the pipe.

Such a pipe cutter is for example known from DE-Gbm 78 11 885. Precautions have even been taken by changing the plugging in of the toolholder to be able to perform parting operations, which can be either to a flat, lead radial cutting surface or to a conical cutting surface. The latter is also common referred to as "chamfer".

The well-known pipe cutter has proven itself, at least in those cases in which the outer The surface of the pipe to be cut is as close as possible to a mathematically exact cylinder surface is equivalent to. However, there are deviations in the roundness of the plastic pipes available on the market and / or to be found in diameter. When clamping a pipe with a pipe that is a few millimeters too large Diameter, the cross-section is deformed to an oval within the tool, so that ultimately a pipe has to be cut in both cases, the outer surface of which deviates more or less strongly from an exact cylinder surface.

If you make a separating cut with a chamfer with the known tool, the transition lines run between the conical surface (= chamfer) and the End face formed by the cut on the one hand and the lateral surface on the other hand in the manner of a Wavy line, "where the chamfer is most pronounced where the radius, based on the ideal longitudinal axis of the pipe, is greatest. Of the

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As a result, the user has the impression that the tool work improperly. In addition, the same chamfers as possible are desired so that the chamfered pipe section can be can be pushed into a sleeve or the like with a sealing ring without difficulty. In the end however, the separation process itself leads to difficulties, namely because the one remaining at the end of the separation process Remaining cross-section on the pipe circumference is uneven, so that the parting tool at one point the inner Surface of the pipe penetrates while it is in another location still within the material is located. The actuating forces required for rotation of the known tool are consequently non-uniform; With thin-walled and / or brittle pipe materials, the tool either gets stuck, or there is no clean cut at all perform more.

The innovation is therefore based on the task of using the pipe cutter described at the beginning to improve that it can also be used for pipes whose outer surface deviates from an exact cylinder surface, Easier operation and the production of a clean separating cut and, in particular, a clean one Chamfering made possible.

The problem posed is achieved in accordance with the innovation in the pipe cutter described at the outset in that an elastic member is arranged between the tool holder and the spindle, and that the tool holder a distance guide device for guiding the parting tool relative to the pipe surface.

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The elastic member is the same as in the prior art

ί existing rigid coupling between tool holder

and spindle canceled. Thereby the position of the

Parting tool no longer under all circumstances

5 proportional to the spindle position, which is only for exact

cylindrical tubes are advantageous. Rather can

'i the parting tool relative to the spindle by one

, ν due to the design of the elastic member

I amount to be shifted relatively. The elastic

ί 1o link is expedient with a certain pretension

I built in and mustn't be too "soft".

I 'the correct dimensioning can be determined by trials

I · easy to find.

Sf Through the guide device, which is described below

^I I 15 described embodiment only comes into play, ύ after the separation process has already been initiated, £ is achieved that in the last phase of the separation

i process, but especially in the production of the

^ Chamfering, the surface of the pipe itself is the guide

S 2o of the parting tool takes over. This follows - under

'' corresponding deformation of the elastic member -

% of the tool holder or the parting tool exactly

■ ^; any changes in the radius of the pipe.

Since the guide device is relative to the parting tool)? 25, is preferably designed to be adjustable, can optionally -A corresponding training of the parting tool is required - both a flat severing cut as well as one with a chamfer. The breakthrough of the tool through the inner Rohrrober-3o surface is then uniform over the entire circumference. The chamfer formed (conical surface) has surface lines of absolutely the same length, so that appearance and

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Function of the separation point of the pipe correspond to the set requirements Completion of the separating or chamfering process no more changing power requirements, so that the operator also has the feeling that the tool is perfectly completing the cutting process. A runaway of the material at the point of separation or even splintering in the case of brittle pipe materials no longer occur.

It does not matter that the parting tool has not yet been removed from the guide device at the beginning of the operation to be led. If the penetration depth is shallow or before the chamfer has been completed, different Actuating forces are not so important. The further penetration of the parting tool or however, that cutting edge that produces the bevel comes at the respective point on the pipe circumference then to a standstill when the final penetration depth specified by the setting of the guide device is reached in the pipe wall at all points of the circumference.

It is particularly advantageous if, according to the further innovation, the elastic member is a compression spring is when the tool holder has a longitudinal bore in which the compression spring and one against the compression spring displaceable sliding sleeve are arranged and when the spindle engages in the sliding sleeve.

In the manner indicated, the elastic member is integrated into the tool holder, i.e. on the known one No further changes were made to the device than a simple exchange of the tool holder with the parting tool, because of the external dimensions of the tool holder can be retained

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In principle, however, it is also possible to use the spindle to be stored in a special spindle nut, which is elastically supported against the housing.

In the case described above, it is particularly advantageous if the guide device consists of a There is spacer pin, which is arranged in the end face of the tool holder next to the parting tool and if the end face of the spacer pin can be brought into contact with the pipe surface. Of the The spacer pin can easily be accommodated in the cross section of the tool holder.

As already stated above, the guide device is preferably designed to be adjustable, about the engagement of the guide in relation to the final position of the separating cut or the chamfer to be able to adjust sensitively. This is done in a particularly simple manner in that the spacer pin is a threaded pin that can be screwed into the tool holder.

It goes without saying that precautions must be taken to ensure that the guide device or the threaded pin cannot adjust itself unintentionally. For this purpose either a certain stiffness of the thread is required brought about, or by a clamping or a laterally attached grub screw is a fix the guide device allows.

Further advantageous refinements of the subject matter of the innovation emerge from the remaining subclaims. An exemplary embodiment of the subject matter of the invention and its details are given below

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described in more detail with reference to FIGS. 1-5. Show it :

Fig. 1 is a partial section through a

complete pipe cutter in the direction of the pipe axis and a partial side

opinion,

FIG. 2 is a plan view of the object according to FIG. 1,

3 shows a radial section through the axis of rotation of the tool and through the work

tool holder on an enlarged scale,

4 shows a plan view of the tool holder with parting tool and guide device and

15 Fig. 5 shows a cross section through the object

according to Fig. 3 along the line V-V, again on an enlarged scale.

In FIGS. 1 and 2, a pipe cutter 10 for cutting off a pipe 11 is shown. He consists of a mounted or pushed onto the tube 11 rotary guide 12 and of a Housing 13 with a cutting device 14. The rotation guide 12 has two hollow cylindrical ones Half-shells 15 and 16 which are pivotably connected to one another via a first joint. The joint is shown in Fig.1 offset by 90 °.

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The half-shells 15 and 16 can be braced against one another with the aid of two handles 18 and 18a. The handle 18 is firmly connected to the half-shell 15, which at its upper end in FIG 5 encircling, i.e. closed, guide ring 19.

i On the opposite to the guide ring 19 movable

; '· Half-shell 16 - a parting line is diametrically opposite

j the first joint 17 is arranged - is a tab

j 1o integrally formed on which the handle 18a via a second

[; Joint 51 is pivotally attached. Between

f Handles 18 and 18a are still in place

I push rod 52, the third and fourth

^; Joints 53 and 54 is mounted in the handles.

! 15 form the push rod 52 and the handle 18a

Γ a toggle system via joints 51, 53 and 54,

i which is in the depressed position according to

: Fig. 2 holds itself and here the half-shells 15

and 16 reliably presses against each other and with the

! 2o tube 11 clamped.

On the closed guiding ring 19 is a \ ring 20 rotatably sliding, the part of the housing 13

; forms. For the captive union of

Guide ring 19 and ring 20, a locking ring 21 is provided.

·: ■■ The housing 13 also has one on the ring

! ■ arranged radial extension 20, which at his

j free end an elbow 23 with an internal thread 24 for a spindle 25 carries. The spindle 3o 25 continues in a further spindle 26, which has a smaller thread diameter.

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The threads of the spindles 25 and 26 have an opposite pitch. At the far end of the spindle there is a handle 27.

On the radial extension 22, two guide jaws 28 are arranged on the same side as the angle piece 23 which include a recess 46 between them, which is part of a radial longitudinal guide 45 forms for a tool holder 29 with a parting tool 30. The tool holder 29 is held between the guide jaws 28 by a closure plate 32, which is shown in FIG. 2 for clarity half has been removed. A cuboid extension 49, which is attached to the handle 18 firmly connected half-shell 15 is formed, is used to clamp the complete tool in a clamping device, for example a vice. A spacer 64 ensures that the handles 18 and 18a cannot be pressed together further than is shown in FIG.

In FIGS. 3 to 5, the same parts as before are provided with the same reference numerals. Additionally is to recognize the following:

The tool holder 29 has a longitudinal bore 31 which has a common axis with the spindles 25 and 26 Has. The longitudinal bore 31 is aligned with its open end on the spindle 26 and takes an elastic one Member 33, which is designed as a compression spring 34. The compression spring is supported with one end on the The bottom of the longitudinal bore 31, while its other end presses against a sliding sleeve 35, which - like

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its name says it all - with a sliding fit in the longitudinal bore 31. She's going to slide out prevented by a ring nut 36. The sliding sleeve 35 is provided with an internal thread 37, which is complementary to the thread of the spindle 26. For the sake of clarity, the spindle 26 is shown in FIG Sliding sleeve 35 shown unscrewed; in reality, however, it stands with the sliding sleeve in engagement, as shown in FIGS. 1 and 2. In the position shown in FIG. 3 can however, replace the tool holder 29 with another one or bring it into a different position.

The tool holder 29 has a square cross-section and is consequently within the Guide jaws 28 cannot be rotated. In order to also prevent the sliding sleeve 35 from twisting relative to the To prevent tool holder 29, the sliding sleeve is on diametrically opposite sides provided with longitudinal grooves 38, in which coulisse 39 engage, which are part of the tool holder 29 are. Reference is made to FIG. 5 in particular. The backdrops can be done in the simplest possible way be produced by a locally limited embossing process, as shown in FIGS '5 can be seen.

According to FIG. 4, the tool holder 29 has a recess in the area of its front end face 40 provided, through which a shoulder 41 and a support surface 42 for the parting tool 30 are formed. This consists of a correspondingly ground Cutting plate, which in the recess through

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a screw 43 is held.

The parting tool 30 has a cutting edge 44 which is at an angle of about 60 ° to the direction of displacement of the tool holder 29 (radial) to the axis of rotation) runs and lies essentially in a plane laid through the axis of rotation. The parting tool 30 also has a further cutting edge 47 which lies in the same plane as the cutting edge 44, but runs approximately at right angles to this and at a significantly more protruding point lies. The cutting edge 47 extends between two approximately plane-parallel planes 55 and 56, wherein the expression "plane parallel" applies to cutting tools includes the usual "relief".

In the end face 40, a distance guide device 57 is arranged, which consists of a spacer pin 58 with an end face 59 and an external hexagon 60. The distance pin is open at least part of its length designed as a threaded pin and in a corresponding The threaded bore 61 of the tool holder 29 is axially adjustable.

The mode of operation of the device described is as follows, with the spindle 26 engaging in the Sliding sleeve 35 according to Fig. 3 is assumed:

First of all, the tool holder 29 is located with its cutting edge 47 above the pipe surface 11a.

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■; If he is now using the spindles 25 and 26 against the

? · The pipe surface 11a is braced and then becomes the

Housing 13 by tilting behind the plane of the drawing in

; Fig. 3 pivoted, so the cutting edge cuts

5 when the rotary movement is continued and the spindles 25 and 26 continue to rotate gradually into the pipe surface 11a, an initially V-shaped groove being formed. After the very end of the

,; Cutting edge 47 penetrated the inner pipe surface 11b

ί 1o is the part 11c on the right in FIG. 3

.- of the pipe 11 separated, one of the location of the

% Cutting edge 47 corresponding burr remains.

h This is not annoying because the end of the part is sloping

11c has to be edited one more time anyway.

• 15 The part supplied to the end use is the

\ «Pierced pipe 11.

: By further actuation of the spindles 25/26 the

i parting tool 30 finally as far as radial to

|; Tube 11 moved until that shown in FIG

• ^; 2o position is reached. (Part 11c is here

_: · Already no longer available) This creates

• i by means of the further set back cutting edge

$ 44 a chamfer 62 in the form of a conical surface,

I on the one hand by the pipe surface 11a

I '25 and on the other hand by the flat face of the

if tube 11 is limited, the location of which is the location of the

, Area corresponds to 55. It may be that the

*. version 62 initially not yet on the entire scope

I is the same width. However, since this

i 3o at least in places the end face 59 of the spacing

: Guide device 57 to rest on the pipe upper

«: Surface 11a comes, the cutting edge 44 can on this

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Do not penetrate any further into the pipe - there is no more material at the relevant points removed. If the chamfer is initially flatter at other points, the face is located 59 does not touch the pipe surface, so that the parting tool 30 is under the influence of the compression spring 34 can be moved further radially inward until the distance guide device 57 opens the entire circumference of the pipe surface 11a comes to rest evenly. Right now there is one Chamfer 62 of exactly the same width was created on the entire circumference.

It goes without saying that the spacer pin 58 can also be screwed further out of the tool holder 29 can, so that, for example, the outermost end of the cutting edge 47 just even through the inner surface of the pipe 11b penetrates. Since this is also a support for the tool holder 29 opposite the pipe surface 11a occurs, the cutting edge 47 penetrates too deeply into the pipe cavity prevented. This penetration was also observed in the prior art, as the entire tool has a certain, albeit slight, elasticity even without the elastic member. The resulting The subject of the invention effectively prevents the remaining cross-section from tearing off or stalling.

It is also understood that the spacer pin 58 can also be brought into any intermediate positions depending on how strong the chamfer should be selected I.

Claims (7)

α «β · 6054 R0DGAU-3, September 7th 108/75 -1- PROTECTION CLAIMS 1. Pipe cutter, in particular for plastic pipes, consisting of a housing that can be guided around the pipe with a rotary guide for the housing that engages the pipe and a parting tool that can be adjusted in the radial direction to the axis of rotation by means of a spindle and a longitudinal guide, in which the longitudinal guide consists of a Housing radially arranged recess and consists of a tool holder displaceable in the recess and in which the parting tool has a cutting edge which extends at an angle different from 90 ° and 0 ° to the direction of displacement of the tool holder and lies essentially in a plane laid through the axis of rotation , in such a way that bevels can be produced with the cutting edge in the region of the cutting edge of the pipe, characterized in that an elastic member (33) is arranged between the tool holder (29) and the spindle (25, 26), and that the tool holder has a spacer guide device (57) for the Fü Has the guide of the parting tool (30) relative to the pipe surface (11a). 2 - ί i ϊ I 1 · · 108/75 -2- 2. Pipe cutter according to claim 1, characterized in that the elastic member (33) is a compression spring (34), that the tool holder (29) has a longitudinal bore (31) in which the compression spring and a sliding sleeve displaceable against the compression spring ( 35) are arranged, and in that the spindle (26) engages the sliding sleeve ■■. i 3. Pipe cutter according to claim 2, characterized in that that the sliding sleeve (35) has an internal thread (37) j: 1o, in which a complementary thread the spindle (26) engages. I. 4. Pipe cutter according to claim 2, characterized by rc h , j. I that the sliding sleeve (35) on its outer circumference !? has at least one longitudinal groove (30) into which one f 15 gate (39) engages the tool holder (29). I. 5. Pipe cutter according to claim 1, characterized in that I that the distance guide device (57) from '■! ■ a spacer pin (58) is in the i front side (40) of the tool holder (29) next to t 2o the parting tool (30) is arranged and ι its end face (59) with the pipe surface > (11a) can be brought into contact. i 6. Pipe cutter according to claim 5, characterized in that 'i that the spacer pin (58) is inserted into the tool 25 holder (29) is screwable threaded pin. 7. Pipe cutter according to claim 1, characterized in that the cutting edge (44) extends at an angle of 30 to 60 degrees, preferably 45 degrees, to the direction of displacement of the tool holder (29). I - 3 -