WO2004092542A1

WO2004092542A1 - Cylindrical cutting body

Info

Publication number: WO2004092542A1
Application number: PCT/EP2004/004107
Authority: WO
Inventors: John Vastmans; Bernd Ries; Ernst Heiderich; Reinhold Walter
Original assignee: Boart Longyear Gmbh & Co. Kg Hartmetallwerkzeug- Fabrik; N. V. Hoogmartens Wegenbouw
Priority date: 2003-04-16
Filing date: 2004-04-16
Publication date: 2004-10-28
Also published as: DE20306065U1

Abstract

The invention relates to a cylindrical cutting body, in particular for a coal cutter or a road milling machine consisting of at least one main holder (2) which is arranged on the external surface (1) of the cutting body and to which a change-tool holder (3) is interchangeably connected every time for changing a cutting or milling tool. Said change-tool holder (3) comprises a shank (9) arranged in the cavity (11) of the main holder (2). The inventive cutting body is embodied in such a way that the longitudinal axes of the shank (9) of the change-tool holder (3) and of the tool are accurately mutually aligned and the cavity (11) of the base holder (2) is provided with an internal thread (10) in which the shank (9) of the change-tool holder (3) can be screwed by means of the corresponding external thread (19) thereof. In a preferred embodiment, said main holder (2) comprises a cavity (16) which substentially extends in a transversal direction with respect to the longitudinal axis of the tool (8) in which a fixing element for the change-tool holder (3) is arranged in such a way that it partially extends through the cavity (11) of the base holder (2). A tool holding device provided with said main holder (2) and change-tool holder (3) is also disclosed.

Description

Roller-shaped cutting body

The invention relates to a roller-shaped cutting body, in particular for a cutting machine or road milling machine, according to the preamble of claim 1.

Such cutting bodies generally have a large number of basic holders arranged in uniform division on their lateral surface, which, for example, form a broaching loading screw or a broach. A tool change holder with interchangeable tools, in particular turning tools, is connected to each basic holder.

A generic cutting body is known from DE 298 05 007 U1 or DE 43 22 407 C2, in which the tool change holder or chisel holder with a shaft, also referred to as a plug-in attachment, is inserted into a plug-in receptacle of the basic holder and is secured in this against unintentional removal , The longitudinal axis of the tool change holder is clearly offset from the longitudinal axis of the chisel tool and in some cases even inclined towards one another. With these cutting bodies, however, the tool change holders shake off in relation to the basic holders during operation, which leads to damage to the holder system. These tool change holders are difficult or difficult to re-fix or fix in the base holder if wear and tear occurs repeatedly between the change holder and the base holder. This leads to reduced service life and reduced quality of the milled surface and results in a reduction in performance.

The object of the invention is therefore to provide a roller-shaped cutting body. per with an improved definition between basic holder and change holder.

This object is achieved according to the invention by a cutting body with the features of claim 1 or a tool holder arrangement with the features of claim 22.

By accommodating the tool change holder in the basic holder, so that the longitudinal axis of the shaft of the tool change holder and that of the tool are aligned, forces exerted via the tool are transferred into the basic holder without displacement. In this case, no unfavorable leverage ratios can occur which, in the case of the cutting bodies of the prior art, bring about a high moment of attack on the connection between the basic holder and the tool change holder, even when the tool is subjected to a relatively low load. In addition, the alignment of the tool and tool change holder shaft, which is aligned in its longitudinal axes, is inexpensive to manufacture, since the tool change holder thus becomes a predominantly rotationally symmetrical part. Both the tool change holder and the basic holder can experience considerable material savings, which makes the entire cutting body lighter and cheaper. In addition, the necessary spatial extension of the basic holder is reduced, so that, if desired, more basic holders with tool change holders and tools can be attached to the lateral surface of the cutting body than was previously possible.

DE 41 27 434 A1 has already described a tool holder in which the direction of insertion of the tool corresponds to the direction of insertion of a sleeve into a basic holder, but here the sleeve is merely an intermediate element which reduces wear on the basic holder and does not reduce the working position - Stands and holds the tool change holder of the cutting body according to the invention and the generic systems for this purpose. Accordingly the sleeve used there to reduce wear is mainly to be secured against twisting in the basic holder, but has no tight fit. In the case of the tool holder from DE 41 27434 A1, the sleeve is also inserted directly into the round holder in the longitudinal direction and secured there. These fastenings also shake loose or break easily, so that a secure hold is not guaranteed.

In contrast, the tool change holder in the cutting body claimed here is screwed into the basic holder according to the invention in that the shaft of the tool change holder has an external thread and the receptacle of the basic holder has an internal thread. Even in the event of breakage or loosening of any additional securing element that is not absolutely necessary, the tool change holder would therefore have to be rotated several times relative to the basic holder in order to detach from it. The proposed fastening according to the invention is therefore considerably safer and more durable and can be used without verification compared to the previously known ones.

To additionally secure the connection between the tool change holder and the basic holder, the basic holder can have a recess which extends essentially transversely to the longitudinal axis of the tool and into which a securing element can be introduced in such a way that it also extends partially through the receptacle of the basic holder. For example, a threaded valley can reach between two thread flanks of the external thread on the tool change holder shaft. In this case, the dimensions of the securing element and the external thread of the tool change holder shaft must be coordinated. In particular, however, the shank of the tool change holder can also have a notch which is provided especially for the securing element and which is at least partially penetrated or gripped behind by the securing element in the assembled state of the cutting body. Further advantages and details emerge from the subclaims and an embodiment of the invention shown in the drawing, which is described below; show it:

1: a side view of a roller-shaped cutting body (indicated) with basic holder, tool change holder and tool,

2: a section in the direction II-II through the object from FIG. 1,

3: a perspective view of the tool change holder from FIG. 1,

4: a view of the underside in the direction IV on the object from FIG. 4,

5: a section in the direction V-V through the object from FIG. 4,

6: a bottom view from the direction VI in FIG. 1 of the basic holder,

Fig. 7: a section in the direction Vll-Vll through the object of Fig. 6 and

Fig. 8: the object of Fig. 1 in longitudinal section.

In Fig. 1 is indicated by a dashed line, the outer surface 1 of a cylindrical but not necessarily cylindrical cutting body on which a base holder 2 is arranged. A tool change holder 3 is detachably connected to the basic holder 2. A tool, in this case a turning tool 4, is inserted into the tool change holder 3. Between the head 5 of the turning tool 4 and there is a wear protection disk 7 on the end face 6 of the tool change holder. The turning tool 4 can be freely rotated about its longitudinal axis 8 of the tool. The tool change holder 3 has a shaft 9 (see in particular FIGS. 3 and 5) with an external thread 19, with which it is screwed into a receptacle 11 having a corresponding internal thread 10 (see FIGS. 6 and 7). The longitudinal axis 18 of the shank 9 represents the extension of the longitudinal axis 8 of the tool, ie it is aligned with it.

In addition to the screw connection between tool change holder shaft 9 and basic holder 2, tool change holder 3 is secured by a securing element. In the embodiment shown, this is a screw 15 which, as shown in FIG. 2, is screwed into a recess 16 in the basic holder 2. However, bolts, for example shear bolts, can also be used as securing elements. The recess 16 also extends partially through the receptacle 11 for the tool change holder shaft 9 (see FIGS. 2 and 7) and thus fixes the shaft 9 of the tool change holder 3. In principle, the fuse could be designed in such a way that the securing element is a threaded valley of the external thread 19 of the shaft 9 passes through. To do this, the securing element would then have to be very thin or the external thread 19 of the shaft 9 should be very large. It is therefore preferable, as in the embodiment shown, to provide a notch 20 in the shaft 9 of the tool change holder 3, which is penetrated in some areas by the screw 15, so that unintentional loosening of the tool change holder 3, even if it should twist, is not possible. 3 and 5, the notch 20 should preferably extend around the shaft 9 in a groove-like manner transversely to the longitudinal axis 18. This ensures that even with slightly different screw-in depths, at least one safeguard against falling out can be brought about by the securing element. If, for example, wear occurs between the basic holder 2 and the tool change holder 3 in such a way that the tool change holder 3 extends somewhat deeper into the basic holder 2 if it had to be screwed in to ensure that it was still securely in place, securing would still be possible.

In order to be able to simply screw the tool change holder 3 into or out of the base holder 2, it is advisable to design the shape of the tool change holder so that a screwing tool can be attached. This is ensured in two respects in the embodiment shown. On the one hand, the head part 23 of the tool change holder 3 has a polygonal shape on the outside, here a hexagon shape, so that, for example, an open-ended or socket wrench can be placed on it with which the tool change holder 3 can be screwed in. In addition, the lower end region of the shaft 9 in the illustrated embodiment is formed with an internal polygon 24, namely an internal hexagon, so that it also extends from the underside of the basic holder 2 to which the receptacle 11 extends in this case (FIGS. 6 and 7) a suitable screwing tool a rotation of the tool change holder 3 relative to the base holder 2 and thus screwing in or unscrewing is possible.

The basic holder 2 is usually welded onto the outer surface 1 of the cutting body. The load-bearing capacity of this welded connection can be improved if an indentation 26 is provided on the underside 25 of the basic holder 2, which indentification, as can be seen in FIG. 6, enlarges the circumferential line 27 of the underside 25 of the basic holder 2. As a result, a weld seam can be placed on both sides of the resulting webs 28, which increases the durability of the welded joint as a whole. If the indentation 26 of the underside 25 of the basic holder 2 is designed such that a material-free area 29 results below the shaft 9 of the tool change holder 3, as in the illustrated embodiment (FIGS. 6 and 7), the underside accessibility to the shaft 9 can be made directly via this of the tool change holder 3, for example to the inner polygon 24 thereof. In the case of the cutting bodies described, it is desirable if tools that may be worn, such as the turning tool 4 here, can be easily removed from the tool change holder 3. In order to be able to use a driving tool here, the end face 6 of the head part 23 of the tool change holder 3 and the head part 23 itself have at least one material recess 33 in which a driving tool for the turning tool 4 can be placed. This driving tool can then be struck against the wear protection disk 7 from the underside of the wear protection disk 7 facing the end face 6, as a result of which the force is transmitted to the turning tool 4 and removes it, which is usually held in a clamping manner, from the tool change holder 3. In order to be able to introduce the expulsion force with a component as large as possible in the direction of the longitudinal tool axis 8, the material recess 33 should therefore extend at an angle <45 ° with respect to the longitudinal tool axis 8. An angle range of 20 ° to 30 ° is preferred here, preferably an angle α of approximately 25 ° as shown in FIG. 5.

The stability of the tool arrangement according to the invention is also justified by the special design of the head part 23 of the tool change holder 3 and the inclusion of the tool in the tool change holder 3. This is shown in particular in FIG. 8. For this purpose, the head part 23 of the tool change holder 3 has a collar 12 widened with respect to the shaft 9, with the rear contact surface 13 of which the tool change holder 3 preferably lies non-positively and positively on the basic holder 2. In order to be able to pass on loads evenly to the base holder 2, the contact surface 13 preferably extends at right angles to the longitudinal axis 18 of the tool change holder 3. The collar 12 preferably has an essentially cylindrical shape for reasons of stability, and its height h 'makes up about a third of the height H of the entire head part 23. Above the collar 12, the head part 23 of the tool change holder 3 has an upper part 14 with a smaller diameter than that of the collar. This allows material to be saved without sacrificing stability. The upper part 14 is preferably designed in a polygonal shape. The tool itself, in the illustrated embodiment of the turning tool 4, is received with a shaft 34 in the tool change holder 3. The particular embodiment of the invention provides that the shank 34 of the turning tool 4 extends essentially only within the head part 23 of the tool change holder 3 and not into its shank 9. This configuration is particularly advantageous, since any damage that may result from the impact of the tool or the chisel 4 on particularly hard material can only be transferred to the head part 23 of the tool change holder 3 via the leverage exerted by the chisel 4. In the event of damage, the chisel 4 and possibly also the head part 23 of the tool change holder 3 breaks off. However, breaking off without damaging the base holder 2 is certainly avoided since the shaft 34 of the chisel 4 does not extend to a relevant extent into the base holder 2. This is of great advantage since any damaged tool change holder 3 can be exchanged much more easily and cost-effectively than broken or damaged base holder 2. Preferably, the length L of the shaft 34 of the chisel 4 is not only less than the total height H of the head part 23 of the tool change holder 3, but corresponds approximately to the height h "of the upper part 14 of the head part 23 or is even less.

A good center of gravity, high stability and nevertheless easy assembly and disassembly of the tool holder arrangement is achieved in particular when the longitudinal axis 18 of the tool change holder 3 cuts the lateral surface 1 of the cutting body approximately at the rear end 30 of the underside 25 of the basic holder 2. The inventive design of the cutting body with basic and tool change holder enables a solid and stable holding of the tool with easy interchangeability, for example when worn. Compared to conventional systems, the material and manufacturing costs can also be reduced. The easy interchangeability of the tools or worn tool change holder also reduces any downtimes of the machine, which increases its economy.

Claims

Expectations

1. Roller-shaped cutting body, in particular for a cutting machine or road milling machine, with at least one basic holder (2) arranged on the lateral surface (1) of the cutting body, with which a tool change holder (3) for receiving a cutting or breaking tool is interchangeably connected, the Tool change holder (3) has a shaft (9) which is received in a receptacle (11) of the basic holder (2), characterized in that the shaft (9) of the tool change holder (3) and the tool are aligned with longitudinal axes (8, 18). have and the receptacle (11) of the base holder (2) has an internal thread (10) into which the shaft (9) of the tool change holder (3) is screwed with a corresponding external thread (19).

2. Cutting body according to claim 1, characterized in that the base holder (2) has a recess (16) which extends essentially transversely to the longitudinal tool axis (8) and in which a securing element fixes the tool change holder (3) in such a way that it also extends partially through the receptacle (11) of the basic holder (2).

3. Cutting body according to claim 2, characterized in that the shank (9) of the tool change holder (3) has at least one notch (20) which is at least partially penetrated by or behind the securing element.

4. Cutting body according to claim 3, characterized in that the notch (20) extends groove-like transverse to the longitudinal axis (18) of the shaft (9) around it.

5. Cutting body according to one of claims 2 to 4, characterized in that the securing element is a screw (15) and the recess (20) in the base holder (2) has a matched internal thread.

6. Cutting body according to one of the preceding claims, characterized in that the tool change holder (3) is designed for the positive attachment of a screwing tool.

7. Cutting body according to one of the preceding claims, characterized in that the tool change holder (3) has a head part (23) projecting over the base holder (2).

8. Cutting body according to claim 7, characterized in that the head part (23) has an outer polygon.

9. Cutting body according to claim 7 or 8, characterized in that the head part (23) has a collar (12) widened relative to the shaft (9) of the tool change holder (3), with the rear bearing surface (13) of the tool change holder (3) the basic holder (2) rests.

10. Cutting body according to claim 9, characterized in that the rear contact surface (13) is aligned substantially at right angles to the longitudinal axis (18) of the tool change holder (3).

11. Cutting body according to claim 9 or 10, characterized in that the collar (12) has a substantially cylindrical shape.

12. Cutting body according to one of claims 9 to 11, characterized in net that the height (h ') of the collar (12) is about a third of the height (H) of the entire head part (23).

13. Cutting body according to one of claims 9 to 12, characterized in that the head part (23) on the side facing away from the shaft (9) has an upper part (14) which is reduced in diameter compared to the collar (12).

14. Cutting body according to one of claims 7 to 13, wherein the tool is received with a shaft (34) in the tool change holder (3), characterized in that the height (H) of the head part (23) of the tool change holder (3) at least Length (L) of the shank (34) of the tool corresponds.

15. Cutting body according to claim 13 and 14, characterized in that the height (h ") of the upper part (14) of the head part (23) of the tool change holder (3) corresponds approximately to the length (L) of the shank (34) of the tool.

16. Cutting body according to one of the preceding claims, characterized in that the tool change holder (3) has an open inner polygon (24), preferably in the end region of its shank (9).

17. Cutting body according to one of the preceding claims, characterized in that the tool change holder (3) has a head part (23) projecting above the basic holder (2) with an end face (6) facing a tool to be used, which has at least one end face ( 6) extending material recess (33).

18. Cutting body according to claim 17, characterized in that the material recess (33) is at an angle less than 45 °, preferably around the Extends 25 ° to the longitudinal tool axis (8).

19. Cutting body according to one of the preceding claims, characterized in that the base holder (2) on its outer surface (1) facing the cutting body underside (25) has a circumferential line (27) of the underside (25) enlarging indentation (26).

20. Cutting body according to claim 19, characterized in that the indentation (26) is formed by a material-free area (29) of the basic holder (2) below the shaft (9) of the tool change holder (3).

21. Cutting body according to one of the preceding claims, characterized in that the longitudinal axis (18) of the tool change holder (3) has the lateral surface (1) of the cutting body approximately at the rear end (30) of the underside (25) facing the lateral surface (1) of the cutting body. of the basic holder (2) cuts.

22. Tool holder arrangement with a basic holder (2) and a tool change holder (3) according to one of claims 1 to 21.