CN212793066U

CN212793066U - Tool for chip removing machining

Info

Publication number: CN212793066U
Application number: CN202020569598.7U
Authority: CN
Inventors: J·奥古斯丁-佩亚; J·魏施努尔
Original assignee: Zhuzhou Diamond Cutting Tools Europe Co ltd
Current assignee: Zhuzhou Diamond Cutting Tools Europe Co ltd
Priority date: 2019-06-24
Filing date: 2020-04-16
Publication date: 2021-03-26
Anticipated expiration: 2030-04-16
Also published as: CN112122635A; DE202019103472U1

Abstract

The invention relates to a tool for chip removing machining, comprising a base support (10), a carrying box (11), a clamping jaw (12) and a clamping support (13), which comprises a receiving opening (25) for releasably clamping a cutting insert (14), which is defined by a lower clamping jaw (22), an opposite upper clamping jaw (23) and a rear stop, wherein a slot and a widening are connected in the rear region of the receiving opening next to the rear stop, by means of which slot and widening the upper clamping jaw can be opened relative to the lower clamping jaw, characterized in that in the region of the upper part of the widening at least one slot is connected which is curved or is formed as an open polygonal curve, said slot extending in a left-curved manner from the front over an angle of at least 120 DEG, the tool ensures sufficient stability during cutting.

Description

Tool for chip removing machining

Technical Field

The utility model relates to a tool for cutting process.

Background

Such tools are particularly needed for cutting inserts for punching and longitudinal turning as well as for cutting and separating processes on rotating workpieces. The cutting inserts which are subjected to wear in the cutting process must be replaced at the latest when, due to wear, the manufacturing accuracy required during the cutting process is no longer ensured. If the cutting edge breaks off as a result of increased wear, this can lead to the workpiece being unusable during further cutting operations.

In order to be able to achieve automatic clamping stresses of the cutting insert, simple replacement and installation and, on the other hand, to ensure optimum retention, therefore, a grooving tool is proposed in DE 3219150C 3, which includes a receiving opening, wherein a rear widened recess is provided, which forms a narrow bridge to the upper edge of the upper clamping jaw, so that the cutting pressure is increased proportionally by the lever-like deflection of the upper clamping jaw. The clamping surface of the upper clamping jaw should be slightly raised inwards with respect to the clamping surface of the cutting insert. In order to remove the cutting insert by opening the clamping legs, an oval key is inserted into the rear widened recess and the upper clamping jaws are opened by a corresponding twisting.

A support is also described in DE 3906822C 3, which comprises a receiving opening, which is defined by lower and upper clamping jaws and a rear stop, and which adjoins an L-shaped slot. In the bending region of the L-shaped slot, an oval shape is selected, which serves as a guide for an expanding key having an oval cross-sectional contour when expanding the clamping jaws.

DE 19955581B 4 describes a cutting insert clamping holder with a lower basic jaw and a resiliently expandable upper clamping jaw which, together with a rear stop, forms a receiving opening for a cutting insert. The upper clamping arm has two clamping surfaces interrupted by a gap. A wide opening in the form of an L extends over the stop at the rear; the other opening should be below the rear stop. The upper L-shaped opening is configured such that it extends in an upward and forward direction, thereby creating on the one hand a narrow bridge section to the edge of the upper part of the upper clamping arm and a narrow second bridge section between the forward extending part and the rear clamping face. Such a construction has the disadvantage that the cutting insert cannot be held reliably due to the fine design of the bridge section.

Other embodiments known from the prior art, in which a narrow slot extends in the rear region of the receiving opening, which slot is intended to ensure the elasticity of the upper clamping jaw, have the disadvantage that chips are stuck in the slot, which chips can lead to a malfunction of the tool.

SUMMERY OF THE UTILITY MODEL

The object of the present invention is to provide a tool of the type mentioned at the outset, which ensures sufficient stability, high elasticity of the upper clamping jaw and optimized positional fixing of the clamped cutting insert during machining. The clamping bracket should furthermore be inexpensive to produce.

In order to solve this task, a tool for chip removing machining is proposed, which comprises a basic holder, a carrying box, a clamping jaw and a clamping holder, the clamping holder having a receiving opening for releasably clamping the cutting insert, the receiving opening is delimited by a lower clamping jaw, an upper clamping jaw opposite the lower clamping jaw and a rear stop, wherein a slot and a widening are adjoined next to a stop of the rear in the rear region of the receiving opening, by forming the slot and the widening, the upper clamping jaw can be spread relative to the lower clamping jaw, characterized in that one or more slots embodied in the form of arcs or as open polygonal curves adjoin the slots embodied at short distances and the widened region of the upper region at the rear thereof, the slot extends, viewed from the front, at an angle of at least 120 DEG in a manner curved to the left. In other words, the slot, which is formed in an arc-shaped or polygonal curve, extends in its continuation in the direction of the front end of the clamping slot.

Preferably, the angle of the slot embodied in the form of an arc or polygonal curve extends up to 180 °.

The elasticity of the upper clamping finger can be improved by providing 1 to 20, preferably 3 to 5, curved or polygonal slots which extend parallel to one another. In the case of a plate-shaped embodiment of the clamping brackets, such curved or polygonal slots can be easily produced by laser etching, wherein, if necessary, a plurality of clamping brackets stacked one above the other can be machined simultaneously. By means of the widened region behind the stop for the cutting insert, a sufficiently large space is provided, through which the chips can be easily discharged, so that the chips do not first reach the region provided with the curved or polygonal-curved slot at all. An easily producible semicircular configuration of the slot is preferred, which on the one hand enables an optimized elasticity of the upper clamping arm and on the other hand prevents narrow bridges in the region of the upper clamping arm, which bridges can lead to an unstable retention of the cutting insert during the cutting operation.

The width of the curved or polygonal slot or slots should preferably lie between 0.1mm and 3 mm.

In particular, the curved slot or the uppermost curved slot of the plurality of slots should extend partially above a clamping plane defined by the clamping jaw, in particular the upper clamping jaw.

According to a further development of the invention, the clamping bracket is plate-shaped and has a plurality of, preferably three, passages with countersunk holes for the purpose of guiding through the fastening screws. The clamping bracket is in this case screwed onto a carrying box which is in turn fastened to the basic bracket. By this measure, the clamping bracket can be removed separately, for example when it is worn out and has to be replaced due to the strong mechanical stresses during the cutting process. The separate design of the basic carrier, the bearing box and the clamping carrier also offers the possibility of producing the clamping carrier from a wear-resistant material, for example from high-grade chrome steel. The carrying box as well as the basic support can in contrast be manufactured in simple, less expensive steel, which minimizes the overall costs overall.

According to a further embodiment of the invention, the clamping bracket can have a coolant channel for a coolant in the upper clamping jaw. The coolant channel opens into the front face of the clamping jaw, which ensures that coolant can be guided in a targeted manner into the cutting region.

If necessary, a clamping bracket with a greater width than that shown can also be used with the same bracket and the same carrying box. The width of the slot to be machined is taken into account when selecting the clamping bracket.

Preferably, the clamping bracket is screwed onto the carrying cassette, the front side of which forms a planar contact surface for the clamping bracket and the rear side of which has a grooved toothing profile, the toothing of which is arranged obliquely, preferably at an angle of 45 ° relative to the longitudinal or transverse axis, wherein the basic bracket has a corresponding toothing profile on the side facing the carrying cassette, which toothing profile of the basic bracket engages in a form-fitting manner in the toothing profile of the carrying cassette in the assembled state. By this design, forces occurring not only in the vertical direction but also in the transverse direction during the grooving operation can be better supported.

In order to ensure an optimized orientation of the tool parts relative to one another, the carrier box has a central recess on its rear side for the releasable reception of a sliding key which serves as a stop for the positionally accurate positioning of the carrier box relative to the tool base support.

Drawings

Further embodiments and advantages of the invention are explained with the aid of the figures. The figures show that:

FIG. 1 shows a schematic view of a complete tool;

fig. 2 shows the same view without cutting insert and without clamping jaw;

FIG. 3 shows a schematic view of a basic carrier with assembled carrying box;

FIG. 4 shows a schematic view of a basic bracket with an embedded feather key;

FIG. 5 shows a schematic view of the back of the load-bearing cassette;

FIG. 6 shows a schematic view of the back of the clamping bracket;

FIG. 7 shows a perspective view of a clamping pincer, an

Fig. 8 shows an exploded view of the complete tool.

Detailed Description

Tool base holders are known in principle from the prior art and comprise a connection on the machine tool, for example an HSK hollow taper shank, and a corresponding coolant feed. In the present case, the complete tool consists of a tool basic holder 10, a carrying box 11, on which a clamping pincer 12 is fastened, and a clamping holder 13, into which a cutting insert 14 is clamped. The clamping bracket has three

bores

15, 16, 17 with countersunk holes through which the screws can be inserted countersunk and used for screwing with the carrying box 11. By means of a slight offset of the

holes

15, 16, 17 with respect to the threaded holes in the bearing box, it is possible, as is known from the principles of the prior art, to ensure that the clamping bracket is pulled into the desired end position when the clamping screw is actuated.

The other holes 18, 19 (see fig. 6) serve to ensure a first positioning of the clamping bracket by means of

pins

20, 21 projecting from the carrying box 11. For this purpose, the

bores

18, 19 are selectively larger in diameter than the diameter of the

bolts

20, 21.

Fig. 1 shows a schematic view of a complete tool comprising a basic holder, a carrying box, a clamping holder with clamped cutting inserts.

As can be seen in detail from fig. 1 and 6, the clamping bracket 13 has a lower clamping jaw 22 and an upper clamping jaw 23, which together with a rear stop 24 form a receiving opening 25 for the cutting insert 14. The

clamping surfaces

221, 231 of the clamping jaws are designed in an arched or prismatic manner and engage with their upper and lower sides in corresponding recesses of the cutting insert 14.

The upper clamping arm also has a coolant outlet opening 232 and a cooling channel, not shown, which leads from the inlet 233 to the outlet 232. Next to the stop 24 or the rounded

further recesses

26, 27, short slots 28 are provided having a length of 2mm to 15mm, preferably a maximum of 5 mm. Connected to the slot is a widened portion 29 which extends into the region which extends below the plane formed by the clamping surfaces 231, 221. This region ensures that the punched-out chips can be easily removed while the slot 28 is short. The widened portion has a length of between 40mm and 80mm and a maximum height of between 10mm and 25mm, preferably between 10mm and 20 mm. At the upper region of the widened portion 29, slots 30 to 33 are connected at the rear end in each case at equal distances, said slots having a small width b of 0.1 to 3mm and forming an angular range of 180 °. The semicircular slot has a distance a from the upper edge 291 of the widened portion 29. The slots 30 to 33 ensure the elasticity of the upper clamping arm 23 without losing the stability of the clamping bracket. Instead of semicircular slots, open polygonal curves can also be used, which extend over an angular extent of at least 120 ° (or more). It is in any case important that the slot extends away from the upper region of the cutting insert immediately behind the widened portion 29 and, for example, is curved (or polygonal curve-shaped) such that its end points in the direction of the recess 29. In this case, the plate-shaped clamping bracket can also be curved in the longitudinal cross section for the purpose of radially grooving.

As can be seen from fig. 2, the upper clamping jaw 23 has a bevel 234, on which the clamping pincer 12 acts in the clamped state and fixes the clamping bracket in such a way that the upper clamping arm 23 holds the cutting insert 14 securely. The clamping pincer 12, as can be seen from fig. 7, has a stepped bore 121 for receiving a screw, not shown, with which it can be fastened to the carrying box 11. The clamping jaw is provided on its front end facing the clamping bracket with a projecting clamping lip 122, which acts on the ramp 234.

As can be seen from fig. 3, the support bracket has a substantially flat contact surface 11 on the side facing the plate-shaped clamping bracket, which is penetrated only by the already described bolt pins 20, 21 and the blind threaded

bores

112, 113, 114. The opening 115 is in connection with an opening 233 (see fig. 6) for conveying and further guiding the coolant.

The box element furthermore has a recess 116 with a threaded bore 117 arranged therein for receiving or fastening the clamping jaw or a screw element for fastening the clamping jaw.

The rear side of the carrying cassette 11 visible in fig. 5 shows a grooved contour 118, the teeth of which extend at an oblique angle. This contour bears in a form-fitting manner against a contour 101 of the base support 10 (see fig. 8). The basic holder 10 and the box 11 also have a central recess for receiving a sliding key 34, which at the same time serves as a stop for the bearing of the box when clamping.

Fig. 4 shows the basic holder 10 without the feather key 34.

In the assembly of the complete tool shown in fig. 1, the sliding key 34 is first inserted into the base support 10 and then the carrying box 11 is placed over it, which is fastened to the base support 10 by means of screws, not shown. The grooved profile 101 of the basic carrier, which is arranged at 45 °, engages in the profile 118 of the cassette 11 and, depending on the selected angular position, serves to better support the vertical and horizontal forces occurring in the known basic carrier than according to the prior art. After assembly of the carrying box 11, the clamping brackets 13 are slipped on and fastened to the carrying box 11 with clamping screws. The upper clamping jaw is then lifted, if necessary with the aid of a spreading key, and the cutting insert 14 formed as a slot insert is pushed in as far as the stop 24. Thereafter, the clamping pincers 12 are assembled and tightened by means of the clamping screw, thereby ensuring a secure position fixing of the cutting insert 14 during the cutting process.

When the cutting insert 14 is worn, the reverse sequence is followed, i.e. the clamping jaw 12 is first released and then optionally the cutting insert is released from the holder with the upper clamping jaw slightly open and replaced by a new cutting insert. If the clamping bracket is also damaged due to the high stresses during the successive cutting operations, the clamping bracket can be released from the carrying box and replaced by a new clamping bracket. Usually, replacement of the carrying box and/or the basic holder is not necessary.

Claims

1. Tool for chip removing machining, comprising a base support (10), a carrying box (11), a clamping jaw (12) and a clamping support (13), which has a receiving opening (25) for releasably clamping a cutting insert (14), which is delimited by a lower clamping jaw (22), an upper clamping jaw (23) opposite the lower clamping jaw and a rear stop (24), wherein a slot (28) and a widened section (29) are adjacent to the rear stop (24) in the rear region of the receiving opening (25), by means of which slot and widened section the upper clamping jaw (23) can be opened relative to the lower clamping jaw (22), characterized in that one or more slots which are designed in the form of an arc or in the form of an open polygonal curve are adjacent in the upper region of the widened section (29), the one or more slots, which are curved or curved in the form of an open polygon, extend at an angle of at least 120 ° in a manner curved to the left when viewed from the front.

2. Tool for cutting machining according to claim 1, characterized in that the one or more slots formed as arcs or as open polygonal curves extend over an angle of up to 180 °.

3. Tool for cutting machining according to claim 1 or 2, characterized in that 3 to 20 slots of arcuate configuration or of open polygonal curve configuration are provided which extend parallel to one another.

4. Tool for cutting machining according to claim 3, characterized in that 3 to 5 slots of arcuate configuration or of open polygonal curve are provided which extend parallel to one another.

5. Tool for cutting machining according to claim 1 or 2, characterized in that the width (b) of the one or more slots formed as arcs or as open polygonal curves is 0.1mm to 3 mm.

6. A tool for chip removing machining according to claim 1 or 2, wherein the arc-shaped slot or the uppermost arc-shaped slot of the plurality of arc-shaped slots extends partially above the clamping plane defined by the clamping jaws.

7. Tool for cutting machining according to claim 1 or 2, characterized in that the clamping bracket is plate-shaped and has a plurality of through-openings (15, 16, 17) provided with recesses for guiding through the fastening screw.

8. Tool for cutting machining according to claim 7, characterized in that the clamping bracket has three through-openings (15, 16, 17) provided with a clearance for guiding through the fastening screw.

9. A tool for cutting machining according to claim 1 or 2, characterized in that coolant channels for coolant extend in the upper clamping jaw (23), said coolant leading into the front face of the clamping jaw.

10. Tool for cutting machining according to claim 1 or 2, characterized in that the clamping holder (13) is screwed onto the carrying box (11), the front side of which forms a planar contact surface for the clamping holder and the rear side of which has a grooved toothing contour (118), the toothing of which is arranged obliquely to the longitudinal or transverse axis, wherein the basic holder (10) has a toothing contour (101) on the side facing the carrying box (11), which toothing contour engages in a form-fitting manner in the toothing contour (118) of the carrying box in the assembled state.

11. Tool for cutting machining according to claim 10, characterized in that the teeth of the profile of the teeth of the carrier box are arranged at an angle of 45 ° with respect to the longitudinal or transverse axis.

12. Tool for chip removing machining according to claim 1 or 2, characterized in that the carrier box (11) has an intermediate recess on its rear side for releasably receiving a sliding key (34) which serves as a stop for the positionally accurate positioning of the carrier box (11) in relation to the tool base support (10).

13. Tool for cutting machining according to claim 1 or 2, characterized in that the clamping holder (13) is made of high-grade steel.

14. Tool for cutting machining according to claim 12, characterized in that the clamping holder (13) is made of 100CR 6.