CN1169125A - Broaching tool - Google Patents

Abstract

A broaching tool (12), in particular for cutting or broaching a plurality of slots, has several spaced-apart cutter discs (10) which rotate about a common axis (33) and are formed with fan-shaped cutting projections (18, 20, 22, 24) about their circumferential direction. In order to cut or broach with as little effort as possible and in a single operation. The distances (26, 28, 30, 32) between successive projections of the sector on each cutter disk (10) are at least approximately equal to or greater than the dimension of the projections of the sector in the circumferential direction, and the projections on adjacent cutter disks (10) are offset from one another in the circumferential direction at least in circumferential sections of the cutter disks.

Description

Broaching tool

The present invention relates to a broaching tool, in particular for broaching or cutting a plurality of slots, comprising several cutter heads spaced apart from each other, each cutter head rotating about a common axis and moving along a These circumferential direction sides have a plurality of fan-shaped protrusions for cutting.

Various cutting tools are known according to the prior art, which have milling inserts made of cemented carbide spaced apart from one another and having a plurality of sector-shaped projections arranged around the circumference of each milling insert and separated from each other by a radial gap.

The high density of cutting segments along the circumference of the cutter head requires the generation of high contact pressures to force the cutting tool into the material to be broached or cut, such as a brick workpiece. However, there is a disadvantage in that a slot to be used cannot be cut, but only parallel slots are formed instead, and the remaining material between the slots must be sequentially removed to obtain the desired slot.

The basic problem to be solved by the present invention is to provide a broaching tool of the type mentioned at the outset, such that a plurality of slots can be cut or broached with as little force as possible and in one operation.

The problem to be solved according to the invention is that the distance apart of the sequential sector-shaped cutting protrusions in each cutter head is at least approximately equal to or greater than the respective circumferential length of the protrusions.

According to the invention, the sector-shaped projections of each cutter head are arranged at a distance from one another or in an intermediate area, said intermediate area enclosing an angle β with respect to the axis in the circumferential direction, the angle β being at least approximately equal to or greater than the angle α, The angle α is essentially the angle encompassed in each case by the sector-shaped projections in the circumferential direction relative to the axis.

In practice, the sectors are arranged relative to each other by means of the intermediate area, so that a sufficiently large space is formed between the sectors, where the material removed in this space can be collected and then removed from the slots by rotating the cutter heads. remove.

The invention is particularly characterized in that the successive sector-shaped projections of each cutterhead are separated by a distance at least approximately equal to or greater than the respective circumferential length of the sector-shaped projections, and that the projections of adjacent cutterheads are circumferentially opposed to each other Staggered or at least in some areas staggered from each other.

Thus, if the sector-shaped projections of each cutterhead are arranged opposite each other with a spacing or intermediate region which encompasses an angle β with respect to the axis in the circumferential direction which is at least approximately equal to or greater than an angle α, the angle α is at each In the case of an essentially sector-shaped projection, the angle encompassed in the circumferential direction relative to the axis, and adjacent cutter wheels are offset from one another in the circumferential direction according to their projections. According to the teachings of the invention, a better cutting/broaching effect of the broaching tool can be achieved. At the same time, the contact pressure can be reduced. In this way, the force required for a broaching tool with 7 adjacent cutterheads, each with 4 sector elements, is equal to that required for such a cutting tool with two parallel cutterheads. Force, in the latter cutting tool, the arrangement of the sector elements is arranged equally along the circumference and one next to the other.

A further advantage is that, according to the projections, the staggered arrangement of the cutter heads in the circumferential direction means that the axial spacing of the sector elements can be greater than the distance between directly adjacent milling cutter heads. Thus, each groove wall formed when the broaching tool cuts into the material is broken due to the vibration of the adjacent cutterhead and can then be removed by the slot. This makes it possible to cut or broach a slot in a single operation.

The broaching tool preferably has n, n≥3, preferably identically designed cutterheads, wherein each cutterhead contains a number of fan-shaped protrusions, X≥3 and the minimum value of the angle α therein _αmin =360°/(nx), and the maximum value of the angle β β _max =(n-1)·α _min . Broaching tools offered in this type of configuration yield the best results in terms of both smooth running performance and cutting results.

A particular embodiment is characterized in that the cutter heads are arranged with their protrusions offset from one another in the circumferential direction, so that at least two sector-shaped protrusions overlap or even completely cover each other when viewed in the axial direction of the broaching tool. This arrangement ensures that the broaching tool penetrates the material to be cut or broached to a considerable extent simultaneously with at least two sector elements.

The projections of the cutter head can be offset relative to one another in the circumferential direction in such a way that the sector-shaped projections form a V-shape, for example a wedge, in a developed view of the cutter head lying in a plane. Here, the configurations of the segmental elements of adjacent cutter heads in the circumferential direction do not or largely do not overlap one another. Accordingly, both smooth running performance and broaching capability of the broaching tool are improved.

In particular, when the broaching tool is viewed from the side, the protrusions of several cutter heads adjacent to each other and extending from a common axis form a closed or largely closed ring. Largely closed here means that the ring preferably forms discontinuities at regular intervals.

Although the cutter heads can preferably be designed in the same way, they can however be varied with respect to the length and/or the number of projections, and of course an otherwise identical machining radius is also possible. In this way, for example, a broaching tool with 5 or 7 cutter heads can contain two groups of different cutter heads following each other in different designs.

According to another preferred embodiment of the milling tool, the plane formed by the sector elements intersects the surface formed by the cutter head at an angle, preferably in the range of 0.5° to 5°.

In addition, it must be emphasized that each cutting protrusion or each sector-shaped element forms an oblique orientation along its running direction, and the respective cutting surface intersects a circle extending around the axis of rotation of the pulling pin tool at an angle γ, and 0.5°< γ<2°.

It is also possible for each cutter head to have a bore for receiving at least one center pin. This allows the cutterheads to be fixed relative to each other in groups as required. Alignment and fixing of the cutter heads to one another can also be achieved by gluing or clamping.

In order to simplify the operation, it is best to design the broaching tool as a coaxially connected tool. Therefore, it is no longer necessary to perform a complicated alignment operation of the individual milling cutter heads by the user.

Further details, advantages and features of the invention are not only reflected in the claims, but also features included individually or in combination in the following description of the preferred embodiment represented in the drawing.

In the attached picture:

Figure 1 shows a plan view of a milling cutterhead;

Figure 2 is a side view representation of a broaching tool consisting of a milling cutter head as shown in Figure 1; and

FIG. 3 shows an expanded view of broaching tools distributed over 360° in a plane.

FIG. 1 shows purely in principle a cutter head 10 serving as an element of a broaching tool 12 designed as a coaxial tool, the design of which is explained in more detail in FIG. 2 .

The cutter head 10 has a metal, preferably polished, disk-shaped base element 14 from which sector-shaped projections 18 , 20 , 22 , 24 extend from a peripheral edge 16 . The respective scalloped peripheral projections 18 , 20 , 22 , 24 are equally spaced apart from one another along the peripheral edge 16 with respective intermediate regions 26 , 28 , 30 , 32 . However, this is not a feature that must be followed, and the length of the individual scalloped peripheral projections and/or their spacing may vary in the circumferential direction.

In the design example shown in FIG. 1 , the cutterhead 10 has four projections covering an angle α=30° in the circumferential direction with respect to a central axis of rotation 33 . The individual intermediate regions 26 , 28 , 30 , 32 likewise cover an angle β=60° relative to the axis of rotation 33 in the circumferential direction.

The respective sector-shaped projection 18 , 20 , 22 , 24 is designed to serve as a carrier for the sector-shaped elements 34 , 36 , 38 , 40 . Each sector element 34, 36, 38, 40 essentially consists of thermocompressed metal containing corundum and is connected to the sector or projection 18, 20, 22, 24, for example by laser welding. The width of the sector elements is preferably greater than the width of the base element 14 . In addition, it should be clear that the sector element 40 is used to form the cutting surface 41 along the circumferential direction, that is, the sector element 40 has a bevel-like geometric shape. However, the cutting height 41 of the sector element, ie the length of the sector element 40, should be the same along the entire cutting surface 41.

The angle γ between the cutting surface 41 and a circle extending around the axis of rotation 33 is 0.5°<γ<5°, especially 1°<γ<2°.

A recess 42 can be formed in the transition region between the individual segments 18 , 20 , 22 , 24 and the cutterhead base element 14 in order to reduce notch effects in this region.

A through hole such as a hole 44 is provided at the center of the cutter head 10 for mounting each cutter head 10 on a tool holder 46 .

Furthermore, the cutter heads 10 have a through hole 48 for receiving a fixing pin 50 so that the relative position of the milling cutter heads 10 to each other remains fixed during operation of the coaxially connected tools 12 . The cutter heads can also be fixed relative to each other by clamping, bonding or other measures.

FIG. 2 shows a side view of the broaching tool 12 . The broaching tool 12 essentially comprises a coaxially connected tool holder 46 with a hollow shaft end 47 , on which the individual cutter discs 10 are arranged according to the distance d between the discs. To adjust the spacing d, an annular intermediate element 52 is sandwiched between the individual cutter heads 10 . The spacing d of the discs 10 ranges from 2 mm to 6 mm, preferably 4 mm. The thickness b of the cutter head 10 itself is preferably in the range of 1.4 mm to 1.8 mm, especially 1.6 mm.

The end 54 of the cylindrical hollow shaft 47 has a plate-like encapsulation 56 which together with the shaft end 47 forms a T-shape and serves as a stop for at least one cutter head 10 . Plate disc 56 preferably has a through hole in its center for receiving a tool such as an Allen key. In order to connect the coaxially connected cutter 12 to a driving device not shown in the figure. For connection to a drive or machine tool, the hollow shaft end 47 has a thread 58 on its inside, by means of which thread the coaxially connected tool holder 46 can be mounted on a rotating machine tool drive shaft shown in detail on the drawing superior.

FIG. 3 shows an expanded view 60 of the broaching tool 12 in one plane over a range of 360°. As shown in the development 60 , the broaching tool 12 contains a total of seven cutter heads, which in this design example are designed identically to the cutter head 10 described with reference to FIG. 1 . The arrangement of the cutter heads is offset relative to each other in the circumferential direction according to the protrusions, so that the sector elements 34 , 62 , 64 , 66 , 68 , 70 , 72 of adjacent cutter heads form a wedge shape. The disposition of the cutter heads here is such that in the axial direction at least two sector-shaped elements coincide or at least partially overlap. In the embodiment example shown, the configuration of the individual cutter heads is offset relative to one another, so that in a direction of rotation 76 an end edge 74 of a sector element 34 is followed by at least one front edge 78 of an adjacent sector element 62 , 64 . There may be a space between the leading edge and the end/trailing edge in side view of the coaxially connected cutter.

The broaching tool 12 thus has four wedge-shaped means 82 , 84 , 86 , 88 along the circumferential side, each wedge extending 120°. The sector elements 24 , 36 , 38 , 40 forming one tip of the wedge are arranged one behind the other in the circumferential direction, in each case at an angle of 90°. The wedges 82, 84, 86, 88 are arranged in sets, those sector elements constituting the tips of the wedges having the same angular position in the developed view 60 as the terminal sector elements 70, 72 of the preceding wedge.

The embodiment shown in Fig. 3 is only a preferred embodiment and thus should not limit the invention. The broaching tool can also work in the opposite direction to arrow 76 .

Of course, arrangements with 3 or 5 or 9 cutterheads are also conceivable. The number and/or length of the protrusions may also vary from cutterhead to cutterhead. In this way the outer cutterhead can have more cutting projections than the inner cutterhead. And vice versa. Furthermore, successive cutterheads may vary with respect to the number and/or length of the cutting protrusions.

However, the protrusions should be evenly distributed along the circumference of each impeller. The arrangement with seven turntables shown in FIGS. 1 to 3 has proven to be particularly advantageous.

claims

Amendments pursuant to Article 19 of the Treaty

1. A broaching tool (12), in particular a broaching tool for broaching or cutting a plurality of slots, comprising several cutter heads (10) spaced apart from each other, each cutter head surrounding a common The axis (33) rotates, and has a fan-shaped cutting protrusion (18, 20, 22, 24) along its circumferential direction side, wherein the sequential fan-shaped cutting protrusions of each cutter head (10) The portions (18, 20, 22, 24) are separated by a distance (26, 28, 30, 32) that is at least approximately equal to or greater than the respective circumferential lengths of the protrusions.

2. A broaching tool (12), in particular a broaching tool for broaching or cutting a plurality of slots, comprising several cutter heads (10) spaced apart from each other around a common The axis (33) rotates and has the fan-shaped cutting protrusions (18, 20, 22, 24) spaced apart from each other along their circumferential direction sides at a certain distance, characterized in that each cutter head (10) is sequentially The distances (26, 28, 30, 32) separated by each sector-shaped protrusion (18, 20, 22, 24) of the sector are at least approximately equal to or greater than the respective circumferential lengths of the sector-shaped protrusions, and wherein adjacent cutterheads ( 10) are offset relative to each other in the circumferential direction or at least in certain areas, and are thus offset from each other so that when the broaching tool (12) is viewed from the side, the sector-shaped projections of the cutter heads form a closed or A largely closed annular surface.

3. The broaching tool according to claim 1 or 2, wherein the broaching tool (12) has n cutterheads (10), and n≥3, wherein each cutterhead (10) The number of protrusions (18, 20, 22, 24) comprising a sector is X, and X≥3, and wherein each or nearly each protrusion has an arc length corresponding to an angle from the axis (33) α, and α _min =360°/nx, and every or nearly every distance (26, 28, 30, 32) has an arc length corresponding to an angle β from the axis, and β=(n-1 )·α, where X·β+X·α=360°.

4. The broaching tool according to at least one of the preceding claims, characterized in that adjacent cutter heads (10) are arranged in circumferential direction according to their projections (18, 20, 22, 24) are offset from each other such that at least two fan-shaped projections overlap or completely cover each other when viewed in the axial direction of the broaching tool (12).

5. The broaching tool according to at least one of the preceding claims, characterized in that adjacent cutter heads (10) are arranged in circumferential direction according to their projections (18, 20, 22, 24) They are offset from each other so that in a developed view of the broaching tool (12) in a plane, at least in certain regions, the protrusions of the sectors form a V-shape, for example wedge-shaped.

6.

7. The broaching tool according to at least one of the preceding claims, wherein adjacent cutter heads (10) are arranged in circumferential direction according to their projections (18, 20, 22, 24 ) are offset from each other, so that in side view of the broaching tool (12), the sector-shaped projections of the cutter heads form a closed or largely closed annular surface.

8. The broaching tool according to at least one of the preceding claims, wherein the cutter heads are fixed relative to each other by means of a central pin (50), by means of gluing and/or clamping.

9. The broaching tool according to at least one of the preceding claims, wherein the protrusions (18, 20, 22, 24) originate from their cutting in the direction of rotation of the cutter head (10) surface.

10. The broaching tool according to at least one of the preceding claims, wherein the cutting surface (41) intersects a circular arc extending from the axis of rotation (33) at an angle γ and 0.5 °<γ<5°, preferably 1°<γ<2°.

11. The broaching tool according to at least one of the preceding claims, characterized in that the projections (18, 20, 22, 24) are sector-shaped elements substantially made of thermocompressed metal containing corundum , or a carrier for such components.

12. The broaching tool according to at least one of the preceding claims, characterized in that the number and / or variable in terms of length.

13. The broaching tool according to at least one of the preceding claims, wherein the broaching tool (12) comprises at least 5 cutter heads with the same working radius, the broaching tool is included in the cutting At least two groups of cutter heads differing from each other with regard to the number and/or length and/or design of the protrusions.

14. Broaching tool according to at least one of the preceding claims, characterized in that the outer cutter disc differs therein from the inner cutter disc with respect to the number and/or length of the cutting protrusions.

Claims (13)

1. a broaching cutters (12), particularly a kind of broaching cutters that is used to broach or cuts a plurality of slits, it comprises several cutterheads (10) that have spacing each other, each cutterhead is around common axis (a 33) rotation, and has fan-shaped cutting protuberance (18,20,22,24) along its circumferencial direction side, it is characterized in that, wherein the fan-shaped cutting of the order of each cutterhead (10) is with protuberance (18,20,22,24) (26,28,30,32) spaced apart, the approaching at least circumferential length separately that is equal to, or greater than protuberance of this distance.

2. a broaching cutters (12), particularly a kind of broaching cutters that is used to broach or cuts a plurality of slits, it comprises several cutterheads (10) that have spacing each other, each cutterhead is around common axis (a 33) rotation, and has fan-shaped cutting protuberance (18 along its circumferencial direction side, 20,22,24), it is characterized in that, the fan-shaped protuberance (18 of the order in each cutterhead (10), 20,22,24) spaced apart (26,28,30,32), this distance is at least near the circumferential length separately that is equal to, or greater than fan-shaped protuberance, and the protuberance of wherein adjacent cutterhead (10) along the circumferential direction staggers toward each other, perhaps staggers each other in some zone at least.

3. broaching cutters according to claim 1 and 2, it is characterized in that, wherein said broaching cutters (12) has n cutterhead (10), and n 〉=3, wherein to comprise the number of fan-shaped protuberance (18,20,22,24) be X to each cutterhead (10), and X 〉=3, and wherein each or almost the arc length that has of each protuberance corresponding to from the open angle [alpha] of axis (33), and α _Min=360 °/n-x, and each or almost each arc length of having of distance (26,28,30,32) corresponding to from the open angle beta of axis, the α of and β=(n-1), wherein X β+X α=360 °.

4. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that, the configuration of adjacent cutterhead (10) is along the circumferential direction staggered each other according to their protuberance (18,20,22,24), make that at least two fan-shaped protuberances overlap each other or covering fully when from axially the watching of broaching cutters (12).

5. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that, the configuration of adjacent cutterhead (10) is along the circumferential direction staggered each other according to their protuberance (18,20,22,24), makes that forming a V font at some each fan-shaped protuberance of zone at least in the expanded view of the broaching cutters (12) in a plane for example is wedge-like.

6.

7. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that, the configuration of wherein adjacent cutterhead (10) is along the circumferential direction staggered each other according to their protuberance (18,20,22,24), makes that each fan-shaped protuberance of each cutterhead forms an annular surface sealing or that seal to a great extent in the side view of broaching cutters (12).

8. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that wherein each cutterhead utilizes a centrepin (50), utilizes bonding and/or clamping mode makes fixed relative to one another.

9. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that wherein each protuberance (18,20,22,24) originates from their cutting surface along the direction of rotation of cutterhead (10).

10. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that, cutting surface wherein (41) with intersect by angle γ from the extended circular arc of rotation (33), and 0.5 °＜γ＜5 ° are preferably 1 °＜γ＜2 °.

11. according to the described broaching cutters of at least one claim of aforementioned claim, it is characterized in that, protuberance wherein (18,20,22,24) is basically by the metal sector ele-ment of the sinter that contains diamond dust, or is used for the bearing part of this class component.

12. the described broaching cutters of at least one claim according in the aforementioned claim is characterized in that, each cutterhead (10) of the order of broaching cutters wherein (12) is variable in their cutting aspect the number of protuberance and/or length.

13. according to the described broaching cutters of at least one claim in the aforementioned claim, it is characterized in that, broaching cutters wherein (12) comprises the cutterhead of 5 identical radius of clean-up at least, and this broaching cutters is included at least two group cutterheads that cutting differs from one another with the number of protuberance and/or length and/or design aspect.

14. the described broaching cutters of at least one claim according in the aforementioned claim is characterized in that, outside cutterhead wherein is different from inboard cutterhead in cutting aspect the number of protuberance and/or length.

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