EP1149666B1 - Plier like combination tool - Google Patents

Abstract

The pliers type combination tool has two legs (2,3) pivotable relatively to each other around an articulation axis (6). As extensions to the axis are two mandrels (15,16), one at each end, for calibrating and bevelling pipe ends. The mandrels are formed for processing different pipe diameters. The two mandrels are connected to each other, thus forming the articulated axis. The connection between them is an axially extending screw (19). At least one of them has peripheral bevelling cutters (26,27) formed by radial recesses (25), each recess forming a front and a rear cutter. Viewed in an axial direction, in front of the bevelling cutters is an all-round swarf groove (22).

Description

The invention relates to a pincer-like combination tool for performing assembly work on pipes, with two pliers legs which are pivotable about a hinge axis to each other and with a designed as an axis extension mandrel for calibrating and chamfering pipe ends.

A combination tool of the type mentioned in the prior art from the DE 196 49 992 C2 known. Such combination tools are used in particular for installing water pipes, which have a plastic-coated metal tube which is surrounded by a corrugated protective tube. When installing the protective tube is cut with one effective range of the combination tool and the metal tube with a second effective range. So that the machined metal tube can be connected at one end in particular by means of a press connection, this pipe end must be calibrated and chamfered. Calibration directs a tube that has been slightly deformed when cut. By chamfering chips should be removed. An exact machining of the pipe ends by calibration and chamfering is extremely important in press connections, as deformed pipe ends and not removed chips can lead to a leaking of the connection and thus to high structural damage.

So that different pipe diameters can be machined, the above-mentioned combination tool has a calibrating and chamfering mandrel which is designed as an axle extension and which has a front region for a small pipe inside diameter and a rear portion for a larger pipe diameter. For chamfering both areas of the mandrel are provided with several cutting edges.

The invention has for its object to provide a combination tool of the type mentioned, which allows an even easier and more accurate editing of pipe ends.

The object is achieved in a generic combination tool in that both ends of the hinge axis are each designed as a mandrel and these mandrels are designed for the processing of different pipe inside diameter.

In the case of the combination tool according to the invention, the distances between the chamfering edges and the calibrating surfaces to the center plane of the tool are considerably shorter than before for the small mandrel. This has the significant advantage that this mandrel is performed more precisely when editing the pipe ends and in particular less tilted. This applies in particular to the cutting edges, which can be arranged very close to the center plane of the tool in the combination tool according to the invention. The smaller mandrel can thus be used more precisely and easily, resulting in a simpler and faster processing overall.

Are according to a development of the invention, the two pins connected to each other and form the hinge axis, this results in a particularly cost-effective and structurally elegant production of the combination tool.

According to a development of the Erfingung it is provided that the mandrels each have a plurality of forward and a plurality of cut edges. When chamfering, the combination tool is around the axis of the mandrels oscillating back and forth. This allows a much faster processing than with the known tool in which chamfering is always rotated only in one direction, for example in a clockwise direction. The handling is much easier.

According to a development of the invention, it is provided that a circumferential flute is arranged in front of the chamfering cutters. When chamfering the chips get into this flute and thus can be much safer avoided that chips remain in the pipe. Such residual chips can lead to leakage.

Further advantageous features emerge from the dependent claims, the following description and the drawings.

• Fig. 1 eine Ansicht eines erfindungsgemässen Kombinationswerkzeuges,
• Fig. 2 eine weitere Ansicht des Kombinationswerkzeuges,
• Fig. 3 ein Teilschnitt entlang der Linie III-III der Figur 1, und
• Fig. 4 eine teilweise geschnittene Ansicht eines Dorns.

An embodiment of the invention will be explained in more detail with reference to the drawing. Show it:

• Fig. 1 a view of a combination tool according to the invention,
• Fig. 2 another view of the combination tool,
• Fig. 3 a partial section along the line III-III of FIG. 1 , and
• Fig. 4 a partially cut view of a thorn.

The combination tool 1 has two forceps arms 2 and 3, each provided with a handle 4 or 5, which are pivotable relative to one another about a hinge axis 6.

Jaws 7 and 8 form a front active region A and a rear effective region B. The active region A has two processing parts 9, which interchangeably with fastening screws 10 at the jaws 7 and 8 are attached. With these parts 9, a corrugated pipe, not shown here, can be cut in a conventional manner. The other effective region B is used for cutting through composite pipes and is formed by a cutting blade 11 and by two support members 12. A durchzuschneidendes and in Fig. 2 only indicated tube 30 is placed with the tool open on the support members 12. When closing the tool, the pipe is cut by the cutting blade 11. When cutting, the tube ends can be easily deformed and it can also form chips on the cut surfaces. To straighten the tube ends and remove the chips, these tube ends, depending on the inner diameter with a mandrel 15 or a mandrel 16 calibrated and chamfered.

The two pins 15 and 16 form according to Fig. 3 the hinge axis 6. To the two pins 15 and 16 releasably and securely connect to each other, a threaded blind bore 17 and in the mandrel 15 a through hole (18) are incorporated into the mandrel 16. A cap screw 19 engages in these two holes 17 and 18 and thus connects the two pins 15 and 16 firmly together. The mandrels 15 and 16 each have on the inside a projection 23 and 24, which are each formed at a distance from a shoulder 28 and 29 as a square. The passages 31 are formed in the region of the pliers limb 2 corresponding to the square, such that the pliers limb 2 is secured against rotation with the spikes 15 and 16. In the area of the forceps leg 3, however, the passages 31 are circular. The pliers leg 3 is thus pivotally mounted on the hinge axis 6. The pliers leg 3 is also guided flat on the shoulders 28, like the Fig. 3 lets recognize.

For calibrating the mandrels 15 and 16 each have a cylindrical lateral surface 33 bzw.34. These surfaces 33 and 34 are each disposed on a head 20 and 21, which is inserted for calibration in a pipe end. The calibration of a pipe end is known per se and need not be re-explained here.

For chamfering, each of the two mandrels 15 and 16 has a plurality of recesses 25, which each form two opposing cutting edges 26 and 27. Between the cutting edges 26 and 27 and the lateral surfaces 33 and 34 each have a circumferential flute 22 is arranged. During chamfering released chips arrive in each case one of the corresponding flutes 22nd

As the Fig. 3 shows, the distances of the cutting edges 26 and 27 in both thorns 15 and 16 to the center plane C are the same and comparatively short. These short distances are essential for the guidance and handling of the two mandrels 15 and 16 during calibration and in particular during chamfering. For handling is also advantageous that is cut when turning the tool for chamfering in both directions of rotation. In one direction it is the cutting edges 26 and in the other direction the cutting edges 27. The one cutting edges are then precutting and the other cutting edges are cutting back. This allows chamfering with an oscillating movement about the axis of rotation of the hinge axis. 6

The calibration and chamfering is preferably done with the tool closed, as in Fig. 1 is shown. Thus, the two legs 2 and 3 remain closed, a bolt 13 is provided which is pivotally mounted about an axis 14 on the pliers leg 2 and which applies in the locking position on a side surface 35 of the pliers limb 3. The bolt 13 is preferably fixed in the closed position so that the tool 1 does not pop open unintentionally.

Claims (8)

1. Plier-like combination tool for carrying out installation work on pipes (30), with two plier limbs (2, 3) which are pivotable with respect to each other about an axis of articulation (6), and with a mandrel (15, 16), which is designed as an axial extension, for calibrating and bevelling pipe ends, characterized in that the two ends of the axis of articulation (6) are each designed as a mandrel (15, 16), and said mandrels (15, 16) are designed for processing different pipe diameters.
2. Tool according to Claim 1, characterized in that the two mandrels (15, 16) are connected to each other and form the axis of articulation (6).
3. Tool according to Claim 1 or 2, characterized in that the two mandrels (15, 16) are connected to each other by an axially extending screw (19).
4. Tool according to one of Claims 1 to 3, characterized in that at least one mandrel (15, 16) has a plurality of bevelling cutting edges (26, 27) on its periphery.
5. Tool according to Claim 4, characterized in that a plurality of front and a plurality of rear cutting edges (26, 27) are provided.
6. Tool according to Claim 4 or 5, characterized in that the bevelling cutting edges (26, 27) are formed by radial recesses (25), and each recess (25) forms a front and a rear cutting edge (26, 27).
7. Tool according to one of Claims 4 to 6, characterized in that an encircling chucking groove (22) is in each case arranged upstream of the bevelling cutting edges (26, 27), as seen in the axial direction.
8. Tool according to one of Claims 1 to 7, characterized in that a locking latch (13) is arranged on one of the plier limbs (3) and can be used to fix the two plier limbs (2, 3) in the closed state.

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