Support peg holder for a pipe cutter

Abstract

The invention refers to a mandrel holder for a pipe cutter having a nearly C-shaped bracket, which supports counter-pressure rollers on one end and is connected, at the other end, to a longitudinal handle containing an adjustment device carrying a cutting wheel, these components defining a tool plane through which a vertical axis passes, which extends between and axially parallel to the counter-pressure rollers and the cutting wheel. The tool plane contains the cutting point of the cutting wheel. The mandrel holder contains a coupling portion designed to radially and axially encompass an arc-shaped portion of the C-shaped bracket, an outer longitudinal portion extending from the coupling portion axially parallel to the vertical axis up to an end piece, and an inner longitudinal portion which extends from the end piece along the vertical axis back approximately to the tool plane and has a rotatable mandrel.

Claims

1. Mandrel holder for a pipe cutter of the type having a nearly C-shaped bracket (1) which supports counter-pressure rollers (2) on one end and is connected at the other end to a longitudinal handle (3) containing an adjustment unit which carries a cutting wheel (5), these components defining a tool plane through which a vertical axis passes, extending between and axially parallel to the counter-pressure rollers (2) and the cutting wheel (5); and the tool plane containing the cutting point of the cutting wheel, wherein the mandrel holder has: a) a coupling portion (6) designed to radially and axially encompass an arc-shaped portion of the C-shaped bracket (1); b) an outer longitudinal portion (12) extending from the coupling portion (6), axially parallel to the vertical axis, up to an end piece (13); and c) an inner longitudinal portion (14; 24) which extends from the end piece (13) along the vertical axis back approximately to the tool plane and which is adapted to rotatably support a mandrel (17) or to support a rotatable mandrel.

2. Mandrel holder according to claim 1, wherein at least the coupling portion (6) and the outer longitudinal portion (12) and preferably also the inner longitudinal portion (14; 24) consist of one piece of material, in particular plastic.

3. Mandrel holder according to claim 1, wherein the coupling portion (6) is designed to encompass, with positive engagement, the arc-shaped portion of the C-shaped bracket (1).

4. Mandrel holder according to claim 1, wherein the parts (8, 9) of the coupling portion (6) which axially encompass the C-shaped bracket (1) are limited radially inwardly by a divided circle whose radius corresponds to the outer diameter of the widest pipe which can be cut with a pipe cutter to which the mandrel holder is attached.

5. Mandrel holder according to claim 1, wherein the outer longitudinal portion (12) has a cross-section which has approximately the shape of a divided circle, the inner radius of the divided circle corresponding to the outer diameter of the widest pipe which can be cut with a pipe cutter to which the mandrel holder is attached.

6. Mandrel holder according to claim 1, wherein the outer longitudinal portion (14; 24) has a length approximately twice as large as the outer diameter of the widest pipe which can be cut with a pipe cutter to which the mandrel holder is attached.

7. Mandrel holder according to claim 1, wherein the mandrel (17) has the form of a short piece of pipe, preferably made from stainless steel, which is supported rotatably in a recess of the inner longitudinal portion (14).

8. Mandrel holder according to claim 1, wherein the mandrel is supported rotatably on one free end of the inner longitudinal portion (24) such that the mandrel is located on the tool plane and can freely rotate there.

9. Mandrel holder according to claim 1, wherein the inner longitudinal portion (14; 24) has a star-shaped cross-section, preferably with preferably three braces of equal length, the radially outermost ends of the braces being positioned at equal distances in an imaginary hollow cylinder whose outer diameter is smaller than the inner diameter of the narrowest pipe which can be cut with a pipe cutter to which the mandrel holder is attached.

10. Mandrel holder according to claim 9, wherein the inner longitudinal portion (14) has a final portion (15) which extends beyond the tool plane and on which the braces are in part radially shortened and formed like barbs (16) at an axially and radially outermost end.

11. Mandrel holder according to claim 1, to be used for cutting relatively thin-walled pipes with wall thicknesses of less than one millimeter.

Description

[0028] Some examples of embodiment will now be described by means of the Figures wherein

[0029] FIG. 1 shows different views of a mandrel holder for a pipe cutter;

[0030] FIG. 2 shows different views of the mandrel holder in FIG. 1, mounted to a pipe cutter; and

[0031] FIG. 3 shows views of a variant of the mandrel holder in FIGS. 1 and 2.

[0032] FIG. 1 shows a first example of embodiment for a mandrel holder: top left, in a perspective view, top right, in a lateral view, bottom left, in a partial cross-section and bottom right, in a front view of an end piece, an extension of the mandrel holder being cut off in both top views for purposes of presentation.

[0033] FIG. 2 shows the mandrel holder of FIG. 1 in a state in which it is mounted to a commercially available pipe cutter: top right, in a perspective view, bottom left, in a front view of an end piece, and bottom right, in a lateral view.

[0034] As can be seen in FIG. 2, the pipe cutter contains a nearly C-shaped bracket 1 (partly concealed by the mandrel holder) which on one end supports several counter-pressure rollers 2 and transitions to a longitudinal handle 3 on the other end, on which handle there is a turning knob 4 by means of which a cutting wheel 5 is moved towards or away from the counter-pressure rollers 2 via an interior threaded spindle.

[0035] The C-shaped bracket 1 and the other parts of the pipe cutter, which are mentioned above, extend on an imaginary plane termed here “tool plane”, intersected by an imaginary axis perpendicular thereto, which extends somewhere between the counter-pressure rollers 2 and the cutting wheel 5 and parallel to the rotational axes thereof.

[0036] As can be seen in FIGS. 1 and 2, the mandrel holder contains a coupling portion 6 which is designed to encompass with positive engagement an arc-shaped portion of the C-shaped bracket 1 of the pipe cutter radially and axially; that is, the coupling portion 6 is a shell-shaped part with an inner surface adapted to the outer surface of the C-shaped bracket 1.

[0037] The coupling portion 6 contains a radial bent portion 7 which is bent in two dimensions similarly to a portion of a barrel, and two axial portions 8 and 9, each of which having the shape of an angular section of a disk.

[0038] The radial bent portion 7 also has a more or less straight tangential extension 10 which is only shown in its entirety in the two lower views and by means of which the mandrel holder can be supported on the back of the pipe cutter, namely at a straight transition from the arc-shaped portion of the C-shaped bracket 1 to the handle 3.

[0039] The radial bent portion 7 also contains a cutout 11 which can be optionally provided if the pipe cutter has an integrated pipe trimming machine which can be pushed out in a telescope-like manner from its back so that the pipe trimming machine can also be used with the mandrel holder in the mounted position.

[0040] An outer longitudinal portion 12 with a cross-section in the form of a divided circle is formed on one axial portion 9 of the coupling portion 6, the outer longitudinal portion extending from the coupling portion 6 axially parallel to the vertical axis mentioned above up to an end piece 13.

[0041] From the end piece 13, along the vertical axis back to the coupling portion 6 and slightly beyond the tool plane, an inner longitudinal portion 14 extends which has a star-shaped cross-section with three braces or “beams” of equal length, whose radially outermost ends are located at equal distances in an imaginary hollow cylinder whose outer diameter is smaller than the inner diameter of the narrowest pipe which can be cut with the pipe cutter by means of the mandrel holder.

[0042] The inner longitudinal portion 14 has an end portion 15 which extends between the counter-pressure rollers 2 and the cutting wheel 5 when the mandrel holder is attached to the pipe cutter. In the region of the end portion 15, the braces of the inner longitudinal portion 14 are in part radially shortened and are formed, at their axially and radially outermost ends, like barbs 16.

[0043] The mandrel holder preferably consists of plastic, and because of its material characteristics, the barbs 16 make it possible to slide a mandrel 17, in the form of a short piece of pipe, shown only in the top part of FIG. 2, made of stainless steel, onto the end portion 15, after which the barbs 16 spring back and retain the mandrel 17 on the end portion 15. The mandrel 17 and the partly radially shortened braces in the end portion 15 are dimensioned such that the mandrel 17 can then freely rotate on the end portion 15.

[0044] FIG. 3 shows a variant of the mandrel holder in FIGS. 1 and 2: namely perspective views on the top left and right, a front view of an end piece on the bottom left and in partial cross-section on the bottom right.

[0045] The mandrel holder shown in FIG. 3 substantially differs from the one shown in FIGS. 1 and 2 only by having, instead of the inner longitudinal portion 14, an inner longitudinal portion 24 lacking the final portion 15, containing, in its free end, a central bore 25 into which a screw can be threaded by means of which a suitable mandrel (not shown) can be screwed to the axial end of the inner longitudinal portion 24 so that the mandrel is on the tool plane and can rotate there freely if it cannot rotate in itself.