PIPE CUTTER

Description

field of technology

[0001] The invention relates to a pipe cutting device with a displacement part and a counter-holder which are formed on a C-shaped working head, wherein the working head further merges into a base part which can also be used as a handle area and the displacement part is displaceable relative to the base part to change an opening width of the working head and the displacement part has a cutting element. State of the art

[0002] Pipe cutting devices are known, in particular, from plumbing technology and pipeline construction. Such a pipe cutting device can advantageously cut a pipe section made of, for example, mild steel, V2A, cast iron, brass, or even a thermoplastic material in a circular cut, preferably without cutting, using at least one cutting blade that rotates, for example, by rotating the pipe cutting device. The active cutting element can be a cutting wheel or a fixed cutting blade, with the cutting element preferably being hardened, for example, made of a high-speed steel, or possibly a hard metal.

[0003] For example, such a pipe cutting device is known from DE 10 2018 124 817 A1. The pipe cutting device shown and described therein has the option of coarse adjustment via a displacement part for coarsely adjusting the opening width between the cutting element and the counterholder. Furthermore, US 9 308 660 B2, for example, shows a pipe cutting device in which the cutting element is accommodated in a displacement part, and the cutting element can be displaced into a retracted position via the displacement part, for example, for inserting the pipe to be cut into the working head.

[0004] From the generic US 2010 / 154 223 A1 a pipe cutting device is known in which the displacement part can be displaced on a straight path.

[0005] Furthermore, reference should be made to the prior art according to KR 2000 0 055 279 A. In the pipe cutting device known therefrom, the cutting element is accommodated in a holder in which a roller is also accommodated. In a pipe cutting device known from US 3 237 301 A, the displacement part is designed on a straight path for screw displacement. US 3 022 575 A discloses a pipe cutting device in which the displacement part can be adjusted in steps along a straight path. Summary of the invention

[0006] Based on the prior art according to US 2010 / 154 223 A1, the invention is concerned with the task of specifying an advantageously designed pipe cutting device.

[0007] This object is achieved by the subject matter of claim 1, wherein the displacement part is displaceable on a curved path.

[0008] Preferably, a possible displacement of the displacement part by the user, for example along a circular arc line with a more preferably constant radius, is provided in order to be able to adapt the cutting element position within the C-opening of the working head to the diameter of the pipe part to be cut via such a displacement. Via the curved path, the cutting element is advantageously always brought into a favorable cutting position relative to the pipe to be cut, regardless of the displacement position of the displacement part, more preferably regardless of the diameter of the pipe to be cut. The curved path can, as preferred, be directed beyond the cutting element essentially in the direction of the head region opposite the opening of the working head.

[0009] A sliding part with the cutting element can be movably arranged in the displacement part.

[0010] In a manner that is advantageous in terms of handling, there is the possibility of adjusting a cutting element's basic position within the C-opening of the working head depending on the diameter of the pipe section to be cut. This adjustment is preferably carried out by correspondingly displacing the displacing part, in which displacing part the cutting element is preferably movably arranged with the sliding part. Thus, according to this embodiment, the cutting element can be displaced in any displacing position of the displacing part via the sliding part, for example into a retracted position or out of this position into a cutting position. In this case, it is further preferred that the displacement of the cutting element into the retracted position can be brought about intentionally by the user, for example for the purpose of inserting the pipe to be cut into the working head.

[0011] The counterholder can have rollers, with two rollers arranged in pairs on each rocker part.

[0012] This results in a favorable alignment of the rollers in the counterholder, adapted in particular to the diameter of the pipe part to be cut and inserted into the C-opening. In addition, the preferred arrangement of the rollers on a rocker part can further reduce the friction between the working head and the pipe part to be cut during the cutting process. The roller axes, as well as more preferably a geometric rocker axis of the rocker part aligned parallel to the roller axes, preferably extend in a direction transverse to a displacement direction of the displacement part receiving the cutting element. However, the displacement part does not necessarily have to be provided in combination in a design of the pipe cutting device in which two rollers are provided on each rocker part, but is only preferably provided in this context. In the cutting position, ieWhen the pipe part is inserted into the C-opening of the working head, one or more rollers of the counterholder can rest on the outer circumferential surface of the pipe to be cut.

[0013] The roller may have a groove running transversely to the roller axis and interrupting the roller surface.

[0014] By creating such a groove, fast, repeatable, and precise positioning on the pipe to be cut is achieved. The groove can serve as a positioning aid.

[0015] Furthermore, such a groove can also be advantageous during a cutting process, especially when cutting plastic pipes. Any cutting chips that may occur during such a cutting process can be collected in the groove-like recess of the roller. The support of the material being cut against the roller surface is therefore not impaired by such chips.

[0016] A displacement element of the displacement part can be arranged countersunk in the handle area.

[0017] The displacement element enables adjustment of the cutting element position within the C-opening of the working head to the diameter of the pipe to be cut. Such displacement of the displacement element is preferably only possible at the user's discretion, preferably by targeted actuation of a corresponding displacement element. Such a displacement element can be, for example, a lever, via which, for example, a locking position of the displacement part can be assumed or canceled. To prevent the locking position of the displacement part from being accidentally canceled during further operation of the pipe cutting device during the cutting process, the corresponding displacement element is recessed relative to the other operating or gripping surface of the pipe cutting device, for example in the area of the base or the handle area.Preferably, this displacement element does not protrude beyond the gripping area surrounding the displacement element in any position, at least not in the position enabling cutting of a pipe. For example, the displacement element can be located in a housing pocket that is closed on three sides in cross-section. This also advantageously allows a user to grip the gripping area, for example, to rotate the pipe cutting tool around a pipe to be cut, without simultaneously actuating the displacement element. Instead, the user must separately engage the gripping area to actuate the displacement element.

[0018] The sliding part with the cutting element can be arranged movably in the displacement part, wherein the displacement part can be displaced on the curved path, wherein furthermore, if appropriate, the counter-holder has rollers and two rollers can be arranged in pairs on a rocker part and, furthermore, if appropriate, a displacement element of the displacement part can be arranged countersunk in the handle area.

[0019] According to a further preferred embodiment, the sliding part with the cutting element can be arranged in the displacement part so that it can move against spring force. The spring force preferably acts in the direction of the functional position of the cutting element, i.e., in an extended position of the cutting element directed approximately toward the center of the C-opening of the working head, so that the cutting element preferably advances automatically into this functional position after a corresponding load on the sliding part receiving the cutting element has been removed. A spring arranged for this purpose can, for example, be a conventional cylindrical spring, which, as is also further preferred, is supported at one end on the displacement part and at the other end acts against the sliding part.

[0020] Furthermore, it can also be provided that two pairs of rollers are provided in the counterholder. Each pair can, as is also further preferred, be arranged on a rocker part. The rollers or pairs of rollers and their rocker parts can be arranged in the counterholder essentially along the boundary wall of the opening defined by the C-opening. The geometric roller axes, and preferably also the geometric rocker axes, are aligned in the same direction. The geometric rocker axes are arranged circumferentially offset in the C-shaped working head. A circumferential offset angle can, for example, be between 60 degrees and 150 degrees, for example approximately 90 degrees.

[0021] If the cutting element is designed as a cutting wheel, the geometric roller axes as well as the geometric rocker axes are preferably aligned parallel to the wheel axis of the cutting element.

[0022] The displacement element can also be arranged so that it can be moved together with the displacement part. Accordingly, after the displacement part is moved to adjust the cutting element positioning to the diameter of the pipe to be cut, a corresponding displacement of the displacement element acting on the displacement part also occurs. Thus, if necessary, the set displacement position or cutting element position can be indicated solely or additionally via the position of the displacement part, for example, relative to the base of the pipe cutting device.

[0023] According to a preferred embodiment, the displacement element can be fixed in two or more, for example up to five or ten, more preferably in three, displacement positions relative to the base of the pipe cutting device, but also relative to the working head of the same. A corresponding number of locking positions can result for the displacement element.

[0024] The adjustment of the displacement element is further preferably independent of the displacement of the displacement part with the cutting element.

[0025] A retraction lever can also be provided, with which the cutting element can be moved out of the C-shaped opening. The retraction lever preferably acts directly or indirectly on the sliding part, whereby when the user deliberately actuates the retraction lever, the sliding part with the cutting element is displaced, preferably against the spring force.

[0026] According to a preferred embodiment, the retraction lever can be arranged with respect to the base part of the pipe cutting device substantially opposite the displacement element acting on the displacement part.

[0027] When the displacement part is displaced, the sliding part supporting the cutting element is preferably also displaced. Furthermore, the retraction lever acting on the sliding part can also be arranged so that it can be moved together with the displacement part.

[0028] According to a further preferred embodiment, an actuating surface can be formed on the sliding part, which can be acted upon by the retraction lever. By appropriately applying pressure to this actuating surface via the retraction lever, a displacement of the sliding part together with the cutting element relative to the displacement part can be brought about, preferably counter to the force of the return spring. The retraction lever and the actuating surface are designed for controlling interaction, so that, for example, a pivoting displacement of the retraction lever voluntarily initiated by the user causes a substantially linear displacement of the sliding part into a cutting element retraction position.

[0029] For example, the actuating surface can also act as a control cam, which, when the spring is released, returns the sliding part with the cutting element to its original position. The actuating surface of the control cam can also extend in a direction transverse to the direction of movement of the sliding part, for example, in an arc shape, to interact with the retraction lever.

[0030] The starting position of the sliding part with the cutting element is preferably the stop-limited position in the relaxation direction of the spring acting on the sliding part.

[0031] In a preferred embodiment, the displacement part is designed to be curved in the adjustment direction of the displacement part. As a result of this embodiment, the displacement part, together with the cutting element in the displacement part, can be displaced into the retracted position of the cutting element or into the starting position, respectively, according to the line of curvature along which the displacement part can be displaced. In the starting position, the cutting element, optionally with a portion of the displacement part, protrudes beyond the front side of the displacement part in the direction of the line of curvature. Furthermore, a possible displacement of the cutting element relative to the displacement part can also occur along the line of curvature.

[0032] When actuated, the retraction lever can act on an actuating surface of the sliding part with two lever arms spaced apart from one another. The distance between the lever arms is preferably defined by a geometric axis, about which the retraction lever can preferably pivot when actuated. The retraction lever can further preferably be hinged to the displacement part. The hinge axis can be defined by a separately provided axle body, which is supported on the displacement part.

[0033] In a further development of the invention, at least one lever leg can advantageously extend through a slot in the offset part. Preferably, each lever leg extends through a separately formed slot in the offset part. The interaction of the lever leg and the slot can thereby result in advantageous (lateral) guidance for the retraction lever, as preferred.

[0034] A further advantageous embodiment is one in which the cutting element is held by a plug-in spindle, which can be removed simply by applying pressure in the axial direction of the spindle. This results in a quick-change system for the cutting element.

[0035] Preferably, such a cutting element change can only be performed in the previously described starting position of the cutting element, in which starting position the cutting element is exposed in the C-opening of the working head. A hole-like opening in the cutting element, if present, can serve to improve the removal of the cutting element after the holder is released by the plug-in spindle, for example, by guiding a removal tool through this opening.

[0036] The tool for removing the cutting element from the holder can advantageously be the plug-in spindle previously removed for removing the cutting element, in particular a section of the plug-in spindle. Furthermore, a free end of the plug-in spindle, for example one facing away from the handle end, can be designed for insertion into or through the opening of the cutting element. Furthermore, this end can, for example, be designed to be pin-shaped. Accordingly, with such a design, the cutting element removal tool is part of the pipe cutting device. Furthermore, it is ensured that, before the plug-in spindle is used as a tool, this plug-in spindle is removed beforehand, as is also necessary for removing the cutting element.

[0037] The cutting element is also preferably provided with two cutting areas opposite one another in the direction of the previously described curvature line. These cutting areas can be of identical design, but alternatively, they can also have different cutting geometries to adapt, for example, to the material of the pipe to be cut. Thus, the cutting element can be accommodated in the sliding part so that it can be displaced by 180 degrees, for example.

[0038] The cutting element can also be made of high-quality ball bearing steel.

[0039] According to a further preferred embodiment, the rollers of the counterholder can have a circumferential groove-like depression approximately centrally in the direction of their axial extension. These groove-like depressions of all rollers preferably extend in one plane, which more preferably can define a common cutting plane together with the cutting element immersed in the C-opening. This embodiment also enables fast, repeatable, and precise positioning on the pipe to be cut thanks to the groove-like depressions on the rollers, which also serve as positioning aids. A user of the pipe cutting device can advantageously orient themselves visually with regard to the cutting plane using a groove-like depression, even if the cutting element is already covered by an inserted pipe.

[0040] Relative to the direction of extension of the roller axis, the groove in the roller surface can have a groove width which can correspond to one eighth to one sixth, but at least one twelfth, preferably up to one third of a transverse dimension (diameter) of the roller.

[0041] Furthermore, the groove may have a width corresponding to one sixteenth to one twelfth, but at least one twenty-fourth, of the roller length viewed in the axial direction.

[0042] The width may also correspond to 1.4 times or more, up to, for example, 2 times or more, the groove depth viewed perpendicularly thereto, wherein the groove depth may further correspond, for example, to one twenty-fourth up to one fifth, preferably approximately one twelfth of the roll diameter.

[0043] An absolute measurement for a groove width can be, for example, 1 to 2 mm, or even more.

[0044] In one possible embodiment, the groove can be arranged off-center relative to the axial extension of the roller. However, a central positioning is preferred.

[0045] Furthermore, the groove can be arranged, as is also preferred, together with the cutting tip of the cutting element in a common cutting plane. This allows a user of the pipe cutting device to visually orient themselves with regard to the cutting plane using the groove-like recess, even if the cutting element is already covered by an inserted pipe.

[0046] In a further possible embodiment, the roller can be constructed in two parts, viewed in the axial direction, comprising a first roller part 18' and a second roller part. Both roller parts can have the same axial length. However, roller parts with different lengths are also possible in this regard. Regarding the diameters, it is preferred that these be selected to be the same.

[0047] When in use, the two roller parts complement each other to form the roller and can be loosely mounted and held on a roller shaft.

[0048] If necessary, the roller parts are loaded towards each other in relation to the roller shaft, for example by spring force, so that the roller parts preferably lie against each other with their facing end surfaces.

[0049] An inclined surface can be formed on one or both of the end faces facing each other to form the groove between the roller parts.

[0050] Due to the two-part design of the roller, with an appropriate axial play, the roller parts can be moved away from each other by a few tenths of a millimeter, for example to remove a chip that has become stuck in the area of the groove, so that the resulting widening of the groove enables the chip to be removed from the groove more easily.

[0051] This two-part design of the roller also means that the roller parts can, if required, be placed on the roller shaft in such a way that the end faces with the beveled surface point outwards, thus creating no groove in the middle between the roller parts, but rather a continuous roller surface with a constant diameter.

[0052] The pipe cutting device can be equipped with multiple rollers, whereby only one or several rollers, up to and including, as is also preferred, all rollers, can be provided with a groove. In the case of multiple rollers provided with a groove, the grooves are more preferably arranged in alignment with one another in a single plane relative to a cutting plane, whereby they can also be arranged offset parallel to one another in a separate groove plane. Short description of the drawings

[0053] The invention is explained in more detail below with reference to the accompanying drawing, which merely illustrates exemplary embodiments. A part that is explained only with reference to one of the exemplary embodiments and is not replaced by another part in another embodiment due to the special feature highlighted therein is thus also described for this further embodiment as a potentially present part. It shows: Fig. 1 shows a pipe cutting device in perspective view, relating to a first embodiment; Fig. 2 shows the pipe cutting device in side view; Fig. 3 shows the pipe cutting device in front view; Fig. 4 shows the pipe cutting device in rear view; Fig. 5 shows the pipe cutting device in an exploded perspective view; Fig. 6 shows the section along the line VI-VI in Figure 4 ; Fig. 7the section along the line VII-VII in Figure 3 ; Fig. 8the section along the line VIII-VIII in Figure 6 ; Fig. 9 the enlargement of area IX in Figure 6 ; Fig. 10the section along the line XX in Figure 7 ; Fig. 11 a representation according to Figure 6 , but concerning a retracted position of a cutting element of the pipe cutting device; Fig. 12 the enlargement of the area XII in Figure 11 ; Fig. 13 a representation according to Figure 7 , however, concerning the position pursuant to Figure 11 ; Fig. 14one of the Figure 7corresponding illustration, concerning a removal position for the cutting element; Fig. 15 the section along the line XV-XV in Figure 14 ; Fig. 16 the pipe cutting device in a sectional view according to Figure 13 , relating to a pipe attachment position with a set first pipe cutting size and with the cutting element displaced into a retracted position; Fig. 17 one of the Figure 16 corresponding illustration, but after moving the pipe to be cut into the cutting position and when the cutting element is in contact with the pipe; Fig. 18 one of the Figure 17 corresponding illustration concerning the cutting position of the cutting element; Fig. 19 one of the Figure 16 corresponding illustration, but concerning a set second pipe cutting size when arranging a pipe of corresponding size; Fig. 20 one of the Figure 19corresponding illustration, but after moving the pipe to be cut into the cutting position and when the cutting element is in contact with the pipe; Fig. 21 one of the Figure 20 corresponding illustration concerning the cutting position of the cutting element; Fig. 22 another of the Figure 16 corresponding illustration, but concerning a set third pipe cutting size when arranging a pipe of corresponding size; Fig. 23 one of the Figure 22 corresponding illustration, but after moving the pipe to be cut into the cutting position and when the cutting element is in contact with the pipe; Fig. 24 one of the Figure 23 corresponding illustration concerning the cutting position of the cutting element; Fig. 25 the pipe cutting device in a side view according to Figure 2 , relating to a second embodiment; Fig. 26 a third embodiment of the pipe cutting device in a representation according to Figure 2; Fig. 27 the pipe cutting device in a perspective cut-out view, relating to a further embodiment; Fig. 28 the pipe cutting device according to Figure 27 in front view; Fig. 29 the greatly enlarged sectional view of areas XXIX in Figure 28 ; Fig. 30one of the Figure 29 corresponding sectional view concerning a further embodiment. Description of the embodiments

[0054] Shown and described is, firstly, with reference to Figure 1 , a pipe cutting device 1 for cutting pipe pieces 2.

[0055] The pipe cutting device 1 initially and essentially has a housing 5 consisting of a first housing shell 3 and a second housing shell 4. According to a preferred embodiment, the housing shells 3 and 4 can consist of a hard plastic material, furthermore, for example, of a glass fiber reinforced polyamide.

[0056] The housing 5 forms a substantially C-shaped working head 6, one C-leg 7 of which forms a counterholder 8, and the other C-leg 9 of which merges into a base part 10 extending substantially transversely to the C-opening 12 of the working head 6. The base part 10 can, as is also preferred, be used as a handle area 11.

[0057] The C-web 13 connecting the C-legs 7 and 9 is shown with reference to a plan view of the C-opening 12, for example according to Figure 2 , following an arc line extending over approximately 180°. Thus, for example, according to the illustration in Figure 2, the leg wall 14 of the C-leg 9, which delimits the C-opening 12 and preferably extends essentially in a straight line, essentially tangentially into a first web wall section 15 of the C-web 13, which extends approximately over 90 to 100 degrees and which, with regard to the delimitation of the C-opening 12, is described over the entire extent approximately by a constant or approximately constant radius.

[0058] The C-leg 7 forming the counterholder 8 has a leg wall 16 delimiting the C-opening 12, which, more preferably, when aligned in a straight line, is aligned at least approximately parallel to the leg wall 14 of the opposite C-leg 9.

[0059] The first, circular-arc-shaped web wall section 15 is connected to the previously described leg wall 16 via a second arc-shaped web wall section 17. As can be seen, for example, from the illustration in Figure 2As can be seen, this second web wall section 17 occurs opposite an imaginary, in Figure 2 in dash-dotted line style and running approximately tangentially into the leg wall 16, so that the selected design of the second web wall section 17 results in an enlargement of the area of the C-opening 12.

[0060] Different radii of curvature can be selected over the extent of the web wall section 17, wherein a first section adjoining the web wall section 15 can have a smaller radius of curvature than a final section merging into the leg wall 16.

[0061] In this case, in the area of the web wall section 17, a largest extension dimension a can result compared to the imaginary extension 15' of the web wall section 15, which can, for example, correspond to approximately one twelfth to approximately one eighth, furthermore approximately one tenth of the distance dimension b between the leg walls 14 and 16 (compare Figure 2 ).

[0062] Rollers 18 are provided in the working head 6, associated with the counterholder 8. Preferably, a paired arrangement of rollers 18 is provided, wherein these rollers 18 can also be held in a rocker part 19.

[0063] The rocker part 19 is pivotally mounted between the housing shells 3 and 4 via a rocker axis 21 when the rocker part 19 is extended in a housing recess 20 opening towards the C-opening 12. The geometric axis of the rocker axis 21 as well as the geometric axes of the roller axes 22 are directed transversely to an insertion direction r of a pipe section 2 into the C-opening 12, and are further correspondingly aligned according to a plan view of the C-opening 12, as shown in Figure 2 is shown, represented as points.

[0064] As can be seen from the illustration in Figure 5As can be seen, each rocker part 19 is provided with two preferably identically designed and parallel-aligned tabs 23, with tab legs projecting from the rocker axis 21 on both sides, at the ends of which the roller axes 22 are held. The two rollers 18 of a rocker part 19 preferably extend between the tabs 23 and are freely rotatable about their roller axes 22.

[0065] Viewed in the direction of extension of the roller axis 22, each roller 18 is preferably provided centrally with a groove 24 which is countersunk relative to the otherwise circular-cylindrical roller surface.

[0066] In a preferred embodiment, two rocker parts 19, each with two rollers 18, are provided, wherein one rocker part 19 is essentially assigned to the C-leg 7 of the counter-holder 8 and the other rocker part 19 is essentially assigned to the C-web 13. Thus, the rocker axis 21 of one rocker part 19 can be arranged approximately in association with the transition region of the second web wall section 17 into the leg wall 16, while the rocker axis 21 of the other rocker part 19 can be arranged essentially close to the transition region of the first web wall section 15 into the second web wall section 17.

[0067] Due to the provided housing recess 20, the rocker parts 19 with the rollers 18 can partially immerse into the housing recess 20 due to pivoting displacement about the rocker axis 21, so that with reference to a floor plan view according to Figure 2a roller 18 can move completely or partially behind the associated wall section of the C-opening 12 or can also move partially or completely over the associated wall in the direction of the C-opening 12.

[0068] The rocker parts 19 can, as shown, be freely pivotable about their rocker axes 21, preferably limited only by the base of the housing recess 20. According to a possible embodiment, it can also be provided that a spring, for example a leg spring, loads the respective rocker part 19 into a basic position, as shown, for example, in Figure 2 This can further facilitate the insertion of the pipe section 2 to be cut.

[0069] In addition, as can be seen from the Figures 1 to 24illustrated embodiment, for example, in the transition area of the foot-side leg wall 14 into the adjoining web wall section 15, a support block 25 protruding into the C-opening 12 may be provided, with a support surface 26 directed towards the C-opening 12.

[0070] Alternatively, the boundary contour of the C-opening 12 can be designed according to the Figure 25 The second embodiment shown can also be provided solely by the leg walls 14 and 16 and the web wall sections 15 and 17, accordingly omitting a previously described support frame 25.

[0071] For cutting a pipe section 2 in the circumferential direction, the pipe cutting device 1 is provided with a cutting element 27, which, for example, according to Figure 2 in a starting position, which starting position corresponds to the cutting readiness position, protrudes freely into the C-opening 12.

[0072] As can be seen from the illustration in Figure 9 As can be seen, the cutting element 27 is essentially designed as a cutting blade, more preferably as a so-called interchangeable blade, with opposite cutting tips 28 viewed in the longitudinal direction of the cutting element 27. Thus, the cutting tip 28 to be used can be changed by rotating and / or turning the entire cutting element 27 by preferably 180 degrees, for example when one cutting tip 28 is worn.

[0073] According to the illustrated embodiment, the two cutting tips 28 are designed identically with regard to their cutting contour, with a steep flank 61 directed in the cutting direction s and a flat flank 62 adjoining thereto. This type of design of the cutting tip 28 proves to be advantageous, in particular for cutting plastic pipes, such as domestic water pipes, wherein the selected cutting tip design further promotes the clearing of the resulting cutting gap.

[0074] Alternatively, the cutting element 27 can also be designed oppositely with differently designed cutting edges, for example for cutting pipe sections 2 made of different materials.

[0075] The cutting element 27 can, as is also preferred, be plug-mounted in a sliding part 29. For this purpose, the sliding part 29 has a receptacle 30 in the region of the end facing the C-opening 12, in which the cutting element 27 can be held via a plug-in axis 31. The geometric axis of this plug-in axis 31 preferably extends in the same direction as the geometric axes of the rollers 18 and the rocker axes 21.

[0076] The cutting element 27 is preferably penetrated by the plug-in axis 31 centrally in the region of a holding opening 32 with respect to its longitudinal extent. The cutting element 27 is further preferably supported along its longitudinal edge 33 on the facing walls of the receptacle 30, so that the cutting element 27 is preferably held in the receptacle 30 in a form-fitting manner.

[0077] The plug-in shaft 31 is provided in the region of one end with a radial collar 34, which, when the cutting element 27 is in the holding position in the receptacle 30, is received in an associated and adapted recess 35 of the sliding part 29. The radial collar 34 can be designed, for example, as a polygon, or further, for example, as a hexagon, if necessary for rotationally secure mounting in the further, if necessary, adapted recess 35.

[0078] The free end of the plug-in shaft 31 facing away from the radial collar 34 has a reduced diameter compared to the section passing through the cutting element 27 in particular and projects freely for actuation in the area of a cutout 36 of the sliding part 29.

[0079] For example, simply by exerting pressure in the axial direction of the plug-in shaft 31, the latter can be displaced to release the cutting element 27. This is particularly possible in a deliberately brought about protrusion position of the sliding part 29 as shown in the illustrations in the Figures 14 and 15 , in which protrusion position the plug-in spindle 31 is exposed for actuation in the C-opening 12. This protrusion position of the sliding part 29 can be achieved by actuating a retraction lever 38 acting on the sliding part 29.

[0080] After moving the plug-in spindle 31 into a position releasing the cutting element 27, or after removing the plug-in spindle 31, the cutting element 27 can be removed from the receptacle 30. For easier removal, the cutting element 27 is further preferably provided with a bore-like removal opening 37 between the holder opening 32 and the respective cutting tip 28, for example, for threading a tool that facilitates removal.

[0081] According to one possible embodiment, the previously removed plug-in shaft 31 can serve as such a tool for removing the cutting element 27 from the receptacle 30. At its end facing away from the radial collar 34, the plug-in shaft 31 can have a pin formation 63, which is adapted, in particular with regard to the selected diameter, to the opening diameter of the removal opening 37. The cutting removal tool is thus advantageously part of the pipe cutting device 1 (see Figure 15 ).

[0082] The sliding part 29 extends in the base part 10 in an elongated, arcuate manner, more particularly within an adapted elongated, arcuately designed displacement part 39. The displacement part 39 is initially and essentially tubular with a preferably rectangular cross-section for guidingly receiving the sliding part 29. The latter can be displaced accordingly in the longitudinal extent of the sliding part 29, as well as in the longitudinal extent of the displacement part 39 and the base part 10, relative to the displacement part 39 and the foot part 10 along a curved path c. The preferably non-circular cross-sectional design of the cavity 49 of the displacement part 39, as well as of the displacement part 29 received therein, ensures a rotationally fixed displacement of the displacement part 29 within the displacement part 39.

[0083] The displacement part 29 is further preferably supported within the displacement part 39 via a compression spring 40 on a bottom section 41 of the displacement part 39, so that the displacement part 29 together with the cutting element 27 accommodated in the receptacle 30 can be moved relative to the displacement part 39 into an initial position, for example according to Figure 6 , is loaded. In this initial position, the cutting element 27 with the provided cutting tip 28 protrudes freely into the C-opening 12.

[0084] The relative displaceability of the sliding part 29 relative to the offset part 39 is preferably limited in both directions. For this purpose, the sliding part 29 carries, in a region between the receptacle 30 and the support region for the compression spring 40, a limiting pin 42 which preferably extends in the axial direction of the rollers 18 and protrudes on both sides beyond the outer wall surface of the sliding part 29, which engages on both sides in elongated holes 43 formed in the associated walls of the offset part 39 (compare, for example, Figure 7 ). The elongated holes 43 run along a curved center line corresponding to the path c.

[0085] The aforementioned retraction lever 38 preferably passes through a slot-like opening 44 of the base part 10, which opening 44 is preferably provided on the side of the base part 10 opposite the opening area of the C-shaped working head 6.

[0086] Starting from an actuating section 45 accessible from the outside, the pull-in lever 38 passes through the opening 44 with two lever legs 46 which are preferably spaced apart from one another and run parallel in the direction of extension of the geometric axes of the rollers 18. These lever legs 46 are connected to the displacement part 39 via an axis 47 near the base section 41, so that a pivotable arrangement of the pull-in lever 38 as a whole on and relative to the displacement part 39 is provided.

[0087] The lever legs 46 extend beyond the axis 47 through slots 48 in the wall of the displacement part 39 for engagement in the cavity 49 of the displacement part 39 which guides the sliding part 29. This can provide favorable guidance of the retraction lever 38 on the displacement part 39 during actuation.

[0088] The sliding part 29 furthermore has control cams 50 formed on the outside of the wall, preferably on both sides, more preferably associated with the end facing away from the receptacle 30, each with an arcuate actuating surface 51 pointing towards the opposite end. These actuating surfaces 51 are designed to cooperate with a facing control surface 52 of the lever leg 46 of the retraction lever 38 (compare for example Figure 7 ).

[0089] Accordingly, by intentionally pivoting the retraction lever 38 toward the base part 10, a displacement of the sliding part 29 within the displacement part 39 toward the base section 41 on the displacement part side and against the restoring force of the compression spring 40 can be effected, in particular to retract the cutting element 27 held at the end into the cavity 49 of the displacement part 39. The cutting element 27, in particular the cutting tip 28 intended for cutting, thus preferably no longer enters the C-opening 12 beyond the opening edge of the displacement part 39. This retracted position of the cutting element 27 is preferably the position of the pipe cutting device 1 in which a pipe section 2 is inserted into the C-opening 12 (cf. Figures 16 , 19 and 22 ).

[0090] Preferably, this retracted position of the sliding part 29, brought about by corresponding actuation of the retraction lever 38, is limited together with the cutting element 27 by a stop, in particular due to the limiting pin 42 striking the end region of the elongated hole 43 facing away from the C-opening 12.

[0091] After the force acting on the feed lever 38 is removed, the sliding part 29 together with the cutting element 27 automatically returns to the previously described starting position due to the relaxation of the previously compressed compression spring 40, for example according to Figure 7 , back.

[0092] Automatically due to relaxation of the compression spring 40 or by a possible pulling operation of the pull-in lever 38 against the previously described direction of operation, the sliding part 29 can be brought together with the cutting element 27 into the previously described protruding position of the cutting element 27, in which the plug-in axis 31 is exposed for changing the cutting edges (see Figures 14 and 15 ). This position of the sliding part 29 and the cutting element 27 can also, as is also preferred, be the stop-limited starting position.

[0093] As described, the displacement part 29 is displaceable along the curved path c within the displacement part 39. Likewise, the displacement part 39—together with the displacement part 29—can be displaced along this curved path c in an adjustment direction m to adapt the C-opening 12 to different diameters of the pipe sections 2 to be cut. In this regard, a stepwise displacement of the displacement part 39 is preferred. In the illustrated embodiment, three displacement stages are provided in this context.

[0094] Preferably opposite the aperture 44, a slot-shaped opening 53 is further provided in the base part 10. In the region of its opening wall, pocket-like locking receptacles 54 are formed opposite one another and evenly spaced from one another in the direction of extension of the track c. Corresponding to the preferably provided three offset steps, three locking receptacles 54 are provided on both sides in the opening walls, each opening toward the housing cavity accommodating the offset part 39.

[0095] Opposite the retraction lever 38, a button-like displacement element 55 is pivotally connected to the displacement part 39. This element is also pivotally mounted via an axis 56 in the area of the base section 41 of the displacement part 39 and extends within the slot-like opening 53 of the base part 10.

[0096] The displacement element 55 is supported on the displacement part 39 via a compression spring 57 and is accordingly loaded by the compression spring 57 in a radially outward direction with respect to the axis 56.

[0097] The end of the displacement element 55 opposite the connection area in the area of the axis 56 is provided on both sides with freely projecting locking cams 58, viewed in the direction of extension of the axis 56, which locking cams 58 are preferably adapted to the opening cross-sections of the locking receptacles 54 with regard to their extension length and / or cross-sectional design.

[0098] As a result of targeted pressure being applied to the displacement element 55 against the restoring force of the compression spring 57 and a corresponding pivoting displacement of the displacement element 55 about the axis 56, the locking cams 58 are moved out of engagement with the housing-side locking receptacles 54. The locking cams 58, together with the section of the displacement element 55 carrying the locking cams 58, enter a correspondingly positioned recess 59 of the displacement part 39. In this disengaged position of the displacement element 55, a displacement of the displacement part 39 along the curved path c is possible. Both the displacement element 55 and the opposite retraction lever 38 move together with the displacement part 39.

[0099] The locking position for securing the new offset position of the offset part 39 together with the sliding part 29 and the cutting element 27 can be brought about essentially automatically by removing the pressure applied to the offset element 55. Thus, after removing the locking position and initiating the displacement of the offset part 39, the pressure exerted on the offset element 55 can be removed, so that upon reaching the next locking receptacle 54, the locking cams 58 can automatically fall into the locking receptacles 54 due to the relaxation of the compression spring 57.

[0100] For example, markings 60 can be provided on the outside of the wall on the offset part 39, which, for example, approximately overlapping the leg wall 14 of the C-opening 12, can indicate the respectively set offset position and thus more preferably the size of the opening for a pipe section 2 to be cut.

[0101] The described pipe cutting device 1 is used, for example, for cutting pipe pieces 2 in, for example, three different sizes or diameters.

[0102] Thus, a first displacement position, in which the displacement part 39 is almost completely retracted into the base part 10, can be used to cut pipe sections 20 with an exemplary diameter of 50 mm. Figure 16 shows in this first offset position an intermediate position during the insertion of the pipe section 2 to be cut into the C-opening 12. Due to the retracted cutting element 27, the pipe section 2 can be inserted into the C-opening 12 without damage, in a cutting readiness position, as shown in Figure 17The pipe section 2 is supported circumferentially on the rollers 18 of both rocker parts 19 as well as on the support surface 26 of the housing-side support bracket 25. In this position, the retraction lever 38 is preferably unloaded, so that the cutting element 27 is guided via the sliding part 29 to the outer surface of the pipe section 2 to be cut due to the relaxation of the compression spring 40.

[0103] The positioning of the pipe section 2, in particular the positioning of the desired parting plane of the pipe section 2, is also facilitated by the grooves 24 provided in the rollers 18. These grooves 24, together with the cutting tip 28 of the cutting element 27, preferably extend in a common cutting plane E directed transversely to the orientation of the geometric axes of the rollers 18.

[0104] Each groove 24 can, as further shown in the Figures 27 to 29shown, in a longitudinal section through the roller 18, in which longitudinal section the geometric axis of rotation of the roller 18 is shown as a line, in the form of a substantially V-shaped notch, which is preferably formed centrally with respect to the longitudinal extent of the roller 18 viewed in the axial direction.

[0105] In this case, in the roller surface 66 interrupted by the groove 24, a groove width u viewed in this longitudinal direction can result, which can correspond to approximately one eighth to one sixth of the outer roller diameter w (compare Figure 29 ). In addition, the groove depth t considered perpendicular to the roll width u can essentially correspond to one twenty-fourth up to one fifth of the outer roll diameter w.

[0106] In addition, the longitudinal section as shown in Figure 29Preferably, a V-shape of the groove 24 results. Furthermore, the groove walls 64, which delimit the groove 24 in the longitudinal section substantially transversely to the orientation of the rotation axis, can enclose an angle β of preferably more than 45 degrees up to, for example, 90 or 120 degrees, further, for example, approximately 75 to 105 degrees, with one another. Accordingly, these groove walls 64 extend inclinedly from a groove base 65, which is preferably rounded in the longitudinal section, in the direction of the roller outer shell, with increasing spacing of the groove walls 64 from one another.

[0107] Due to such a design of the rollers 18, with grooves 24 aligned with the cutting tip 28 in a common cutting plane, any cutting chips that may form on the material being cut—for example, a plastic pipe section 2—during the cutting process can be collected in one or more grooves 24. The cutting chips essentially plunge through the groove 24 of the guiding and supporting roller 18 during the cutting process. On both sides of the groove 24, the support and guidance of the material being cut—here, pipe section 2—remains unaffected by any cutting chips that may form.

[0108] Figure 30 shows, in a further embodiment, a roller 18 which is divided into two parts in the direction of extension of the roller axis 22, comprising a first roller part 18' and a second roller part 18". Both roller parts 18' and 18" can, as is also preferred, be of the same design, correspondingly having the same diameters and longitudinal extension dimensions.

[0109] In the area of an end face 67, each roller part 18' or 18" is provided radially on the outside with an inclined surface 68 forming a chamfer.

[0110] In a conventional arrangement, the roller parts 18' and 18" are arranged on the roller axis 22 such that the end faces 67 having the inclined surfaces 68 face each other and preferably, as also in Figure 30 shown, abut one another. This can optionally be supported by a spring element acting axially on the outside of the roller part 18' and / or 18". The mounting of both roller parts 18' and 18" between the tabs 23 of the rocker parts 19 can also be such that only a slight axial play of the roller parts on the roller axis 22 results in a range of hundredths to tenths of a millimeter.

[0111] The centrally circumferential groove 24 is formed by the inclined surfaces 68 facing one another, wherein the inclined surfaces 68 form the previously described groove walls 64.

[0112] The base part 10 or the handle area 11 is gripped on the side facing away from the retraction lever 38. The pipe cutting device 1 is rotated around the pipe section 2 in direction d under preferential tensile load of this handle section (see Figure 18 ). The recessed arrangement of the displacement element 55 prevents involuntary actuation of the displacement element 55 during the cutting process.

[0113] Due to the resulting pulling movement of the cutting element 27 in direction d, the cutting tip 28 digs into the wall material of the pipe section 2 under pressure via the compression spring 40, which ultimately leads to the complete severance of the pipe section 2. During the complete cutting process, the pipe section 2 receives sufficient and friction-reduced support via the rollers 18 and (in this offset position) via the support surface 26.

[0114] The Figures 19 to 21 show the above-described cutting process in a second (middle) offset position of the offset part 39 for cutting pipe sections 2 of a medium size, for example, pipe sections 2 with an outer diameter of approximately 40 mm. As can be seen, in the initial position, the offset part 39, together with the received sliding part 29 and the cutting element 27, extends further into the C-opening 12 than is the case in the first offset position.

[0115] In the cutting standby position, as well as during the cutting process according to Figure 21 , a circumferential support of this pipe section 2 can result solely from the rollers 18 of both rocker parts 19.

[0116] The third offset position of the pipe cutting device 1 is shown by the Figures 22 to 24 , in which the offset part 39 with the sliding part 29 and the cutting element 27 protrudes even further into the C-opening 12. In this offset position, pipe sections 2 with an outer diameter of 32 mm, for example, can be cut, wherein in the cutting-ready position and during the cutting process, such a pipe section 2 can preferably be supported on three rollers 18 arranged one after the other in the circumferential direction.

[0117] As in the Figures 17 , 20 and 23As shown, the curved path c is directed essentially toward the pipe axis x of the pipe section 2 in the ready-to-cut position. The path c can intersect the pipe axis x exactly or run at a slight distance from it.

[0118] In an orientation of the pipe cutting device 1 in which a vertical axis of symmetry V of the pipe section 2 accommodated in the working head 5 passes through the base part 10 in its extension and crosses the curved path c upon exiting the base part 10 at the end, the path c intersects the vertical axis of symmetry V within the cross-section of the pipe section 2, preferably below the pipe axis x, and the horizontal axis of symmetry H is preferably offset from the pipe axis x in the direction of the C-web 13. This can result in a vertical distance f between the pipe axis x and the intersection point P of the path c with the vertical axis of symmetry V, which can correspond, for example, to one fifth or less, more preferably to one tenth or less, up to one twentieth or less of the outer diameter g of the pipe section 2.The horizontal distance k between the intersection point P' of the path c with the horizontal axis of symmetry H can, for example, correspond to approximately 0.2 to 1 times, further, for example, approximately 0.5 to 0.8 times the distance f.

[0119] Even with a pipe section 2 with a large diameter, for example a pipe section 2 with a diameter d of approximately 50 mm, such a support angle α of less than 180 degrees can be achieved, for example by appropriately adapting the support surface 26 of the support frame 25. Thus, in Figure 26 an embodiment of the pipe cutting device 1 is shown, which, compared to the embodiment according to Figure 2 a circumferentially shortened and, if applicable, in the view according to Figure 26has a support surface 26 running along a curved line. This results in support on the support surface 26 and the rocker axes 21 of the working head 6 when a pipe section 2 with the largest possible diameter d (here, for example, 50 mm) is arranged. The support angle α resulting between the rocker axis 21 of the rocker part 19 facing away from the C-web 13 of the working head 6 and the support point on the support surface 16 can, for example, be approximately 150 to, for example, approximately 179 degrees, furthermore, for example, approximately 175 degrees. Any undesired clamping or clamping of the pipe section 2, particularly during or at the end of a cutting process, is counteracted due to the selected support angle α of less than 180 degrees.

[0120] In the cutting readiness position of the pipe section 2 to be cut, the pipe section 2 is supported directly or indirectly on the working head 6 - relative to the pipe axis x - via a support angle α, which according to the illustrations in the Figures 20 and 23 accordingly (also) for small and medium pipe diameters d, as is also preferred, can be less than 180 degrees, for example approximately 75 to 150 degrees, further, for example, approximately 90 or 135 degrees. The above-described support angle α preferably refers to the direct support points in the working head 6, and further preferably to the support of the pipe section 2 on the support frame 25 of the working head 6 and / or to the support on one or both rocker axes 21 (cf. Figure 26 ).

[0121] Even with a support angle α of more than 180 degrees (for example, about 190 degrees for a pipe section 2 of the same diameter d of about 50mm), as is the case according to the Figure 2 As shown in the embodiment shown, there is no risk of clamping of the pipe section 2 in the working head 6, since the pipe axis x and thus the center of the pipe in the cutting-ready position lies outside (in front of) the shell-like support (see vertical projection of the pipe axis x along the vertical V in Figure 17). List of reference symbols 1 Pipe cutting device 26 Support surface 2 Pipe section 27 Cutting element 3 Housing shell 28 cutting tip 4 Housing shell 29 Sliding part 5 Housing 30 Recording 6 Working head 31 Thru axle 7 C-leg 32 Bracket opening 8 Counterholder 33 Long edge 9 C-leg 34 Radial collar 10 Footrest 35 depression 11 Grip area 36 Free cut 12 C-opening 37 Removal opening 13 C-bridge 38 retraction lever 14 Femoral wall 39 Transfer part 15 Web wall section 40 compression spring 15' extension 41 floor section 16 Femoral wall 42 Limit pin 17 Web wall section 43 slot 18 role 44 breakthrough 18' roller part 45 Operating section 18" roller part 46 lever leg 19 Rocker part 47 axis 20 Housing recess 48 slot 21 Rocker axle 49 cavity 22 roller axis 50 control cam 23 tab 51 Actuating surface 24 groove 52 Control surface 25 Support trestle 53 opening 54 Snap-in mount w Roll diameter 55 Displacement element x Pipe axis 56 axis EH Cutting plane 57 compression spring horizontal axis of symmetry 58 locking cams P Intersection 59 recess P' Intersection 60 mark V vertical axis of symmetry 61 Steep flank 62 flat flank α Support angle 63 Tenon formation β Groove opening angle 64 Groove wall 65 Grooved sole 66 Roll surface 67 frontal surface 68 inclined surface a Expansion dimension b Distance measure c Train d Direction f Distance g diameter k Distance m Adjustment direction r Insertion direction s Cutting direction t Groove depth u Groove width

Claims

1. A pipe cutting device (1) with an offset part (39) and a counter-holder (8), which are formed on a C-shaped working head (6), wherein the working head (6) furthermore transforms into a foot part (10), which can also be used as a handle area (11), and the offset part (39) can be offset relative to the foot part (10) in order to change an opening width of the working head (6), and wherein the offset part (39) comprises a cutting element (27), characterized in that the offset part (39) can be offset along a curved path (c).

2. The pipe cutting device (1) according to claim 1, characterized in that an offset element (55) of the offset part (39) is arranged in the handle area (11) in a recessed manner.

3. The pipe cutting device (1) according to one of the preceding claims, characterized in that the cutting element (27) is accommodated in a displacement part (29) and the displacement part (29) with the cutting element (27) is movably arranged in the offset part (39).

4. The pipe cutting device according to claim 3, characterized in that the displacement part (29) with the cutting element (27) is arranged in the offset part (39) so as to be movable against a spring force.

5. The pipe cutting device (1) according to one of the preceding claims, characterized in that the counter-holder (8) has rollers (18) and that two rollers (18) respectively are arranged in pairs on a rocker part (19).

6. The pipe cutting device (1) according claim 5, characterized in that two pairs of rollers (18) are provided.

7. The pipe cutting device (1) according to one of the claims 2 to 6, characterized in that the offset element (55) is arranged so as to be displaceable together with the offset part (39).

8. The pipe cutting device (1) according to one of the preceding claims, characterized in that a retraction lever (38) is provided, by means of which the cutting element (27) can be moved out of the C-opening (12), wherein the retraction lever (38) preferably is arranged so as to be displaceable together with the offset part (39).

9. The pipe cutting device (1) according to claim 8, characterized in that an actuating surface (51), which can be acted upon by the retraction lever (38), is formed on the displacement part (29).

10. The pipe cutting device (1) according to claim 9, characterized in that the actuating surface (51) acts as a control cam (50) that moves the displacement part (29) with the cutting element (27) back into a starting position as the spring (40) relaxes.

11. The pipe cutting device (1) according to one of the claims 8 to 10, characterized in that the retraction lever (38) can respectively act upon an actuating surface (51) with two lever limbs (46) that are spaced apart from one another, wherein the retraction lever (38) preferably is hinged on the offset part (39).

12. The pipe cutting device (1) according to claim 11, characterized in that a lever limb (46) passes through a slot (48) of the offset part (39).

13. The pipe cutting device (1) according to one of the claims 3 to 12, characterized in that the displacement part (29) is designed so as to extend in a curved manner in the adjusting direction (m) of the offset part (39).

14. The pipe cutting device (1) according to one of the preceding claims, characterized in that the cutting element (27) is held by a linchpin (31), which can only be removed by exerting pressure in the axial direction of the linchpin (31).

15. The pipe cutting device (1) according to one of the claims 3 to 14, characterized in that the cutting element (27) is accommodated in the displacement part (29) so as to be rotatable by 180 degrees.