EP1468790B1 - Flat chisel - Google Patents

Abstract

The tool (1) used for breaking and removing stone or plaster is designed as a cylindrical shaft (3) with an upper area (4) suitable for being clamped into the chucks of the power tool and a wedge-shaped lower area (2) with a transversal cutting edge. A rib positioned longitudinally on one side of the flat lower segment (2) is pointed towards the upper end and provided with a short pointed tip adjacent to the wider lower end.

Description

The invention relates to a flat chisel according to the preamble of claim 1.

Such flat chisels are used in the processing of rocks, in particular masonry to use, for example, to produce openings, channels and slots. Flat chisels with different elevations on the striking surfaces are known from the prior art. In particular, are from the WO 01/36163 Flat chisel known. Such flat chisels should be improved in terms of their destructive or refractive effect

From the document DE 83 20 045 U a flat chisel has become known according to the preamble of claim 1. On the flat side of the chisel has this elongated V-ribs. These V-ribs have a chisel cutting edge facing first flat long area and an underlying, to the chisel shaft oriented short connection area. Such a V-rib has the disadvantage that the bit with such V-ribs has only a small blasting or refractive power for the material to be treated.

The invention has for its object to develop a flat chisel, which has an increased crushing and destructive force in a near-cutting region over the entire width of the cutting edge.

The object is achieved in conjunction with the preamble of claim 1 according to the invention by the characterizing features of claim 1. In the dependent claims advantageous and expedient developments are given.

The flat chisel according to the invention has at least one wedge rib on at least one of the striking surfaces, which is characterized by a short front section steeply rising in comparison to the striking surface and a long second section sloping flat towards the longitudinal axis.

Such a trained flat chisel is initially determined by the penetrating into the material main cutting edge in its direction of action and has on further penetration into the material an increased blasting or refractive power, which is generated by the rising steeply from the club face impact section of the V-rib , It is important that the impact section is small and set back relative to the main cutting edge in order to brake the penetration of the flat bit into the material by the V-rib only slightly. The impact section is the region of the V-rib, with which this acts primarily on the material to be processed. The impact section is followed by the support section, which, viewed counter to the effective direction of the flat chisel, lies in the slipstream of the striking section. The support section has the task to stabilize the impact section and to ensure that the bit can be easily pulled out of this with a complete penetration of the bit head in the material to be machined. This ensures the support section by its elongated, approximately parallel course to the longitudinal axis of the bit, because this barb-like behavior of the V-rib is prevented. The main cutting edge length is about the cross cutting length or face length approximately in a ratio of 5: 1 to 10: 1, in particular 7: 1 based on the effective lengths of the cutting or striking surface in the effective direction x of the flat chisel.

According to the invention, the chisel on a V-rib, which rises in front view with two triangular surfaces of the club face, the surfaces together form a transverse cutting edge to the main cutting edge and wherein the survey is completed pyramid-like by two more triangular surfaces. Due to the cross-cutting edge and the surfaces, a deep penetration of the V-rib into the material to be processed is particularly favored.

According to a preferred embodiment, the cutting edge or the impact surface of the V-rib on an angle α of about 40 ° to 50 ° to the longitudinal axis of the flat chisel. In particular, an oblique position of the transverse cutting edge or the impact surface of the V-rib is provided at an angle α of 45 ° relative to the longitudinal axis. This ensures that the transverse cutting edge or impact surface relatively easily penetrates into the material to be machined despite a strong splitting and breaking action.

Furthermore, the invention provides, the surfaces, which are considered against the direction of action of the flat chisel - in the lee of the transverse cutting edge forming surfaces or the club face to extend over the face of the flat chisel to the drill collar. As a result, the impact section of the V-rib experiences optimal support.

The invention provides to arrange at least one V-rib on at least one of the striking surfaces of the flat chisel. Due to the number and location of the V-ribs, it is possible to specifically adapt the destructive force of the flat chisel to the material to be machined and the desired behavior of the chisel. For example, it is provided to arrange two wedge ribs running symmetrically and parallel to the longitudinal axis of the flat chisel on its striking surface. As a result, the main cutting edge is supported over its entire width in its destructive effect and it is effectively counteracted twisting of the flat chisel about its longitudinal axis, so that the desired direction is maintained at high refractive power.

Furthermore, the invention provides, the impact portion of the wedge surface by two obliquely to the main cutting edge and obliquely To form the striking surface of the flat chisel surfaces, which together form the transverse cutting edge. Such a design of the impact section favors the deep penetration of the bit into the material to be machined.

According to one embodiment, the invention provides to form the striking portion substantially by a triangular striking surface, which is parallel to the main cutting edge with its base side and support them over two roof gable-like oriented triangular surfaces on the face of the flat chisel. In this way, a wedge rib is created, which has a high debris effect through its oriented in the direction of action of the chisel club face and is slender in the support section following the impact section.

According to a further embodiment, the invention proposes to form the striking portion substantially by a triangular striking surface, which is parallel to the main cutting edge with its base side and support it over three triangular surfaces on the face of the flat chisel, so that the V-rib looks like an upper portion a pyramid gets. In such a design of the V-rib and the parallel to the longitudinal axis of the chisel extending side surfaces of the V-rib, in particular at an obliquely penetrating into the material to be machined chisel, the material destructive and the chisel leading properties

According to the invention, it is provided to form the impact portion of the V-rib substantially by a rectangular impact surface, which is parallel to the main cutting edge with its base side and support it over three rectangular surfaces on the face of the flat chisel, so that the V-rib rising as one of two sides Ramp receives. In such a Training the V-rib also have the parallel to the longitudinal axis of the chisel side surfaces of the V-rib, especially in an obliquely penetrating into the material to be machined chisel, the material destroying and the chisel leading properties.

Further details of the invention are described in the drawing with reference to schematically illustrated embodiments.

Figur 1a_I

eine Draufsicht auf einen erfindungsgemäßen Flachmeißel,

Figur 1a_II

eine Seitenansicht des in Figur 1a_I dargestellten Flachmeißels,

Figur 1a_III

eine vergrößerte Detailansicht der Figur 1a_I ,

Figur 1a_IV

eine vergrößerte Detailansicht der Figur 1a_II ,

Figur 1a_V

eine Frontansicht des in den Figuren 1a_I bis 1a_IV dargestellten Flachmeißels aus einer Blickrichtung lav,

Figur 1b_I bis 1b_III

einen zweiten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten,

Figur 2a_I bis 2a_III

einen dritten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten,

Figur 2b_I bis 2b_III

einen vierten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten,

Figur 3a_I bis 3a_III

einen fünften erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten,

Figur 3b_I bis 3b_III

einen sechsten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten,

Figur 4_I bis 4_III

einen siebten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten,

Figur 5_I bis 5_III

einen achten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten und

Figur 6_I bis 6_III

einen neunten erfindungsgemäßen Flachmeißel in drei den Figuren 1a_III bis 1a_V entsprechenden Ansichten.

Hereby shows:

Figure 1a _I

a top view of a flat chisel according to the invention,

FIG. 1a _II

a side view of the in Figure 1a _I shown flat chisel,

FIG. 1a _III

an enlarged detail view of the Figure 1a _I .

FIG. 1a _IV

an enlarged detail view of the FIG. 1a _II .

Figure 1a _V

a front view of the in the 1a 1a _I to _IV shown flat chisel from a line of sight lav,

Figure 1b _I to 1b _III

a second flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views,

Figure 2a _I to 2a _III

a third flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views,

Figure 2b _I to 2b _III

a fourth flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views,

Figure 3a _I to 3a _III

a fifth flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views,

Figure 3b _I to 3b _III

a sixth flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views,

Figure 4 _I to 4 _III

a seventh flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views,

Figure 5 _I to 5 _III

an eighth flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views and

Figure 6 _I to 6 _III

a ninth flat chisel according to the invention in three the Figures 1a _III to 1a _V corresponding views.

Figure 1a _I shows a plan view of a flat chisel 1. The flat chisel 1 consists essentially of a chisel head 2, a shaft 3 and a clamping end 4 together. The chucking end 4 is designed as an SDS or SDS plus shaft.

In FIG. 1a _II is a side view on the in the Figure 1a _I shown flat chisel 1 shown.

FIG. 1a _III shows an enlarged view of the bit head 2 in plan view. The chisel head 2 has a main cutting edge 5 which is transverse to a longitudinal axis of the chisel L ₁ . This one goes via cutting surfaces 6a, 6b into a front striking surface 7a and a rear striking surface 7b (see also FIGS FIG. 1a _IV ). The cutting surfaces 6a, 6b form a main cutting edge 8 with each other. Laterally of the striking surfaces 7a and 7b, lateral striking surfaces 9a, 9b and 10a, 10b are arranged, which run towards the main cutting edge 8. The striking surfaces 7a, 7b are bounded respectively by the cutting surfaces 6a and the lateral striking surfaces 9a, 9b and 10a, 10b and the chisel shaft 3. In this case, the striking surface 7a or 7a merges with the formation of a pointed surface in the cross-sectionally round chisel shaft 3. The main cutting edge 5 has a width B ₅ . On the impact surface 7a a V-rib 11 is arranged, which runs parallel to the longitudinal axis L ₁ . The wedge rib 11 rises steeply in the side view, similar to a four-sided pyramid of the striking surface 7a, wherein two triangular surfaces 12a, 12b together form a transverse cutting edge 13 which is transverse to the main cutting edge 8 and inclined against a direction of action x of the flat chisel 1 , The surfaces 12a, 12b together with the transverse cutting edge 13 form a striking portion 14 of the wedge rib 11. The surfaces 12a, 12b may also be considered part of a tetrahedron T with a point S, the transverse cutting edge 13 connecting the striking surface 7a to the tip S and forms such a tetrahedral edge. In one of the drill collar 3 facing support portion 15, the V-rib 11 is formed by two elongated triangular surfaces 12c, 12d and extends approximately to the chisel shaft 3. Here, formed by the surfaces 12c, 12d ridge 16 extends in the direction of the transverse cutting edge 13 approximately parallel the longitudinal axis L _{1 of} the flat chisel 1 (see also FIG. 2 ). The V-rib 11 extends in plan view over a length L ₁₁ , wherein the length L ₁₁ of a length L _{14 of} the impact portion 14 and a length L _{15 of} the support portion 15 composed. Here, the impact portion 14 and the support portion 15 are approximately in an aspect ratio of 1: 9.

In FIG. 1a _IV is a side view on the in the FIG. 1a _III shown flat chisel 1 shown from an arrow direction 1a _IV . The cutting edge 13 extends to the longitudinal axis L ₁ at an angle α = 45 ° and has a length L ₁₃ . Apart from the V-rib 11 of the flat chisel 1 is mirror-symmetrical to a plane extending perpendicularly in the plane E ₁ . The striking surface 7a extends to the plane E ₁ approximately at an angle β = 8 ° and the cutting surface 6a extends to the plane E ₁ approximately at an angle γ = 30 °.

In Figure 1a _V is a frontal view of the in the 1a 1a _I to _IV Flat chisel 1 shown from an arrow direction 1a _V shown. From the front view, the effective length L in the impact direction _13W of the transverse cutting edge 13 can be removed, with which this acts in the direction of action of the flat chisel x 1 to the material to be processed. A width B _{11 of} the V-rib 11 corresponds approximately to the effective length of the transverse cutting edge 13 Figure 1a _V is also apparent that the lateral impact surfaces 9a, 9b, 10a, 10b extend approximately at an angle δ = 60 ° to the plane E ₁ , respectively.

The Figures 1b _I to 1b _III show in analogy to the Figures 1a _III to 1a _V a second flat chisel 1, in which on the striking surfaces 7a and 7b centrally each have a V-rib 11 is arranged.

The Figures 2a _I to 2a _III show in analogy to the Figures 1a _III to 1a _V a third flat chisel 1, in which two wedge ribs 11 are arranged symmetrically to a longitudinal axis L ₁ on a striking surface 7a.

The Figures 2b _I to _III 2b show in analogy to the Figures 2a _I to 2a _III a fourth flat chisel 1, in which on striking surfaces 7a, 7b symmetrical to a longitudinal axis L _1st two wedge ribs 11 are arranged in each case.

The 3a _I to _III 3a show in analogy to the Figures 1a _III to 1a _V a fifth flat chisel 1, in which three wedge ribs 11 are arranged symmetrically to a longitudinal axis L ₁ on a striking surface 7 a.

The Figures 3b _I to 3b _III show in analogy to the 3a _I to _III 3a a sixth flat chisel 1, in which three wedge ribs 11 are arranged on striking surfaces 7a, 7b symmetrically to a longitudinal axis L ₁ .

The FIGS. 4 _I to 4 _III show in analogy to the Figures 2a _I to 2a _III a seventh flat chisel 1, in which two wedge ribs 17 are arranged symmetrically to a longitudinal axis L ₁ on a striking surface 7a. Unlike the ones from the Figures 1a to 3b _{III I} Known V-ribs have the V-ribs 17 in a striking section 14 no cross-cutting edge, but each a triangular face 18, which according to the transverse cutting edge of Figures 1a to 3b _{III I} is inclined towards the longitudinal axis L ₁ . In a support section 15, the V-rib 17 with two further triangular-shaped surfaces 19a, 19b runs out into the striking surface 7a in the same way as a saddle roof. A ridge 20, which form the two surfaces 19a, 19b with each other is formed flat. The ridge 20 runs counter to a direction of action x with a slight inclination of about 1 ° to 3 ° to the longitudinal axis L ₁ .

The Figures 5 _I to 5 _III show in analogy to the Figures 2a _I to 2a _III an eighth flat chisel 1, in which on a striking surface 7a symmetrically to a longitudinal axis L ₁ two V-ribs 21 are arranged. Unlike the ones from the Figures 1a to 3b _{III I} Known V-ribs have the V-ribs 21 in a striking section 14 no cross-cutting edge, but each a triangular Hitting surface 22, which according to the transverse cutting edge of Figures 1a to 3b _{III I} is inclined towards the longitudinal axis L ₁ . In a support section 15, the V-rib 21 extends with three further triangular-shaped surfaces 23a, 23b, 23c into the striking surface 7a. The triangular surface 23b runs counter to a direction of action x with a slight inclination of about 1 ° to 3 ° to the longitudinal axis L ₁ and passes into the striking surface 7a. The V-rib 21 can also be described as a four-sided pyramid point, in which the side surface 22 is aligned with a base side G ₂₂ parallel to a main cutting edge 8.

The FIGS. 6 _I to 6 _III show in analogy to the Figures 2a _I to 2a _III a ninth flat chisel 1, in which two wedge ribs 24 are arranged symmetrically to a longitudinal axis L ₁ on a striking surface 7a. Unlike the ones from the Figures 1a to 3b _{III I} Known V-ribs have the V-ribs 24 in a striking section 14 no cross-cutting edge, but each have a rectangular face 25, which according to the transverse cutting edge of Figures 1a to 3b _{III I} is inclined towards the longitudinal axis L ₁ . In a support section 15, the V-rib 24 extends over three further rectangular surfaces 26, 27 a, 27 b in the striking surface 7 a. In plan view, the impact surface 25 is extended by the top surface 26 and the V-rib 24 laterally bounded by the side surfaces 27a, 27b. The top surface 26 runs counter to a direction of action x with a slight inclination of about 1 ° to 3 ° to the longitudinal axis L ₁ and passes into the striking surface 7a. The V-rib 21 can also be described as a ramp or jump.

Also in the in the FIGS. 4 Flat chisels _I to 6 _III shown, a bilateral arrangement of V-ribs according to variants not shown is provided.

In the in the 1a _I to 6 _III shown Embodiments, the V-ribs on the respective flat chisel are identical and arranged symmetrically to the longitudinal axis of the flat chisel. According to further embodiments not shown, it is provided that the V-ribs on the respective flat chisel form differently and / or asymmetrically arranged.

The invention is not limited to illustrated or described embodiments. Rather, it comprises developments of the invention within the scope of the claims.

LIST OF REFERENCE NUMBERS

1

flat chisel

2

chisel head

3

drill collar

4

clamping end

5

main cutting edge

6a, 6b

cutting surface

7a, 7b

Playing surface

8th

Main cutting edge

9a, 9b

lateral impact surface

10a, 10b

lateral impact surface

11

V-rib

12a - 12d

Area of 11

13

Cross cutting edge

14

Beat section of 11, 17, 21,24

15

Support section of 11, 17, 21, 24

16

Burr of 11

17

V-rib

18

triangular face of 17

19a, 19b

triangular area of 17

20

Ridge of 17

21

V-rib

22

Striking area of 21

23a - 23c

triangular area of 21

24

V-rib

25

Clubface of 24

26

Deck area of 24

27a, 27b

Side surface of 24

L ₁

Longitudinal axis of 1

x

Effective direction of 1

B ₅

Width of 5

α

Angle between 13 and L ₁ or E ₁

L ₁₁

Length of 11

L ₁₃

Length of 13

L _13W

effective length of 13

L ₁₄

Length of 14

L ₁₅

Length of 15

E ₁

level

β

Angle between E ₁ and 7a or 7b

γ

Angle between E ₁ and 6a or 6b

B ₁₁

Width of 11

δ

Angle between E ₁ and 9a, 9b, 10a, 10b

T

tetrahedron

S

Top of T

G ₂₂

Base page of 22

Claims (12)

1. Flat chisel (1), in particular insertion chisel for power-driven hammer drills and/or rotary demolition hammers for working masonry, having a spade-like chisel head (2) which has a main lip (5), disposed transversely to a chisel longitudinal axis (L₁), and a front and a rear largely flat impact surface (7a; 7b), at least one web (11) designed as a wedge rib being arranged on at least one of the impact surfaces (7a; 7b), characterized in that the web (11) designed as wedge rib (11; 17; 21; 24) has in side view, with respect to the longitudinal axis (L₁), a first short, steeply rising impact section (14) and a supporting section (15) falling away gently and having a length which is greater than the length of the first impact section (14), the impact section (14) being oriented relative to the main lip (5) and the supporting section (15) being oriented relative to the chisel shank (3).
2. Flat chisel according to Claim 1, characterized in that the wedge rib (11) has, in front view of the main lip (5) of the flat chisel (1), a tetrahedral steep rise with a front-end transverse cutting edge (13), wherein a region (15) following a tip (S) of a tetrahedron (T) runs out in a V shape and in an approximately axially parallel flat manner in the direction of a chisel shank (3).
3. Flat chisel according to either of the preceding claims, characterized in that the wedge rib (11) has a front tetrahedron edge (13) designed as a front-end transverse cutting edge (13) and having a steep angle of rise α ≈ 40 - 50° and in particular α ≈ 45°.
4. Flat chisel according to one of the preceding claims, characterized in that the wedge rib (17, 21, 24) has a front impact surface (18, 22, 25) having a steep angle of rise α ≈ 40 - 50° and in particular α ≈ 45°.
5. Flat chisel according to one of the preceding claims, characterized in that the run-out (15 or 12c, 12d; 19a, 19b; 23a, 23b, 23c; 26, 27a, 27b) of the wedge rib (11; 17; 21; 24) extends over approximately the entire length of the impact surface (7a; 7b).
6. Flat chisel according to one of the preceding claims, characterized in that only one impact surface (7a; 7b) has at least one wedge rib (11; 17; 21; 24).
7. Flat chisel according to one of the preceding claims, characterized in that both impact surfaces (7a; 7b) have at least one wedge rib (11; 17; 21; 24).
8. Flat chisel according to one of the preceding claims, characterized in that the wedge ribs (11; 17; 21; 24) are arranged symmetrically relative to the longitudinal axis (L₁).
9. Flat chisel according to one of the preceding claims, characterized in that the wedge rib (11) has a transverse cutting edge (13) which is formed by surfaces (12a, 12b) which are disposed obliquely to the main cutting edge (8) and obliquely to the impact surface (7a; 7b) .
10. Flat chisel according to one of the preceding claims, characterized in that the wedge rib (17) has, in front view of the main lip (5) of the flat chisel (1), a ramp-shaped steep rise having a ramp surface (18), the ramp surface (18) being of triangular design, and merges in the supporting section (15) in a gable roof shape with triangular surfaces (19a, 19b) into the impact surface (7a, 7b).
11. Flat chisel according to one of the preceding claims, characterized in that the wedge rib (21) has, in front view of the main lip (5) of the flat chisel (1), a ramp-shaped steep rise having a ramp surface (22), the ramp surface (22) being of triangular design, and merges in the supporting section (15) in a pyramid shape again with triangular surfaces (23a, 23b, 23c) into the impact surface (7a, 7b).
12. Flat chisel according to one of the preceding claims, characterized in that the wedge rib (24) has, in front view of the main lip (5) of the flat chisel (1), a ramp-shaped steep rise having a ramp surface (25), the ramp surface (25) being of rectangular design, and merges in the supporting section (15) with a further rectangular ramp surface (26) into the impact surface (7a, 7b), the wedge rib (24) being defined laterally by triangular surfaces (27a, 27b).

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