Flat chisel

Abstract

The present invention relates to a chisel (10) having a working portion (12), a shaft portion (14), an insertion end (24), and a longitudinal axis (L) extending through the working portion (12), the shaft portion (14), and the insertion end (24). The working portion (12) is formed with at least one wedge-shaped cutting edge (18) and a rib (22) extending parallel or at least substantially parallel to the longitudinal axis (L) and facing radially away from the longitudinal axis (L). The rib (22) is locally thickened in at least one rib region (36). The chisel (10) allows for particularly uninterrupted and therefore efficient operation.

Description

Technical Field

[0001] The present invention relates to a chisel comprising a working section, a shaft section, a shank, and a longitudinal axis extending through the working section, the shaft section, and the shank, the working section having at least one wedge-shaped cutting edge and ribs extending parallel or at least substantially parallel to the longitudinal axis and facing radially away from the longitudinal axis.

Background Art

[0002] Such chisels are used at construction sites for chiseling ores, such as concrete. However, during chiseling at the work site, such chisels can stick to the stone, which can lead to stoppages, loss of time, and thus high costs. If chisel dust gradually remains or accumulates in the work site, especially in the chisel recess, it may be necessary to interrupt the chiseling operation to release the chisel dust at the work site.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Therefore, an object of the present invention is to provide a chisel that enables the work to be carried out without interruption, or at least with particularly few interruptions, if possible.

Means for Solving the Problems

[0004] This object is achieved by a chisel comprising a working section, a shaft section, a shank, and a longitudinal axis extending through the working section, the shaft section, and the shank, the working section having at least one wedge-shaped cutting edge and ribs extending parallel or at least substantially parallel to the longitudinal axis and facing radially away from the longitudinal axis, the ribs being locally thickened in at least one rib region.

[0005] Therefore, the rib has localized thickening in the rib region. Localized thickening may be particularly present in the foot region of the rib. The foot region may correspond to the region of the rib facing inward toward the chisel, particularly toward the longitudinal axis.

[0006] The inscribed ellipse of the cross-section of the rib region can have a larger surface area than the inscribed ellipse of the cross-section of the chisel region directly adjacent to the rib region.

[0007] For example, in the case of non-rotationally symmetric chisels such as channel chisels, the longitudinal plane of the chisel can also be considered a longitudinal axis.

[0008] The tests showed that, for example, when chiseling in a depression, such localized thickening can create a free space between the chisel and the wall of the depression. Therefore, the chisel can remain movable even when chiseling in the depression for a long time, and even at considerable depth within the depression. Thus, the chisel can be prevented from seizing, or at least the risk of seizing can be significantly reduced, so that the stop required to release a chisel that has seized in a depression is less frequent, or no stop is required at all.

[0009] It was further observed that localized thickening improved the removal of chisel dust. In particular, chisel dust generated during chisel operation can reach the localized thickening by its own movement, at least in the upper chisel region, i.e., in the direction toward the shank. Due to the continuous forward and backward movement along the longitudinal axis of the chisel, the chisel dust can be further accelerated, especially during backward movement, and as a result can be thrown out even from relatively deep depressions. As a result of improved removal, stoppages can be avoided, or at least their frequency can be reduced.

[0010] The chisel may be in the form of a flat chisel. For this purpose, the chisel may have a cutting edge that does not disappear, i.e., has a finite cutting edge width. The cutting edge width may be, for example, at least 0.5 cm. The cutting edge may be in the form of a prism. The working section may be tapered toward at least the cutting edge along at least one dimension.

[0011] The working section may taper towards the cutting edge in at least two mutually perpendicular dimensions. Thus, the chisel can combine the advantages of both flat and pointed chisels, especially in conjunction with its wedge-shaped cutting edge.

[0012] The ribs can extend in multiple dimensions. In particular, the working section may have four ribs formed, extending in particular parallel to or at least substantially parallel to the longitudinal axis and facing radially away from the longitudinal axis.

[0013] At least one, more than one, or even all of the ribs can be thickened locally.

[0014] At least two of the ribs, and in particular two, can extend in the form of transverse ribs along a plane containing the longitudinal axis.

[0015] At least two of the ribs, particularly two, may extend in the form of vertical ribs perpendicular to the plane or at least substantially perpendicular to it.

[0016] Therefore, at least two transverse ribs and at least two vertical ribs can have a cross-sectional area overall.

[0017] To further enhance the chisel's function as a flat chisel, at least one of the vertical ribs may have a lower height than at least one of the transverse ribs. The height of the rib can be understood as the maximum of all distances from the longitudinal axis to all points on the rib. Except for height and orientation, the vertical and transverse ribs may be formed identically on the chisel.

[0018] Transverse ribs can induce fracture of the processed substrate during chisel work. Vertical ribs can generate additional stress on the substrate, thereby further accelerating fracture.

[0019] Such localized thickening may form in the case of at least one of the transverse ribs. Alternatively, such localized thickening may form in the case of at least one of the vertical ribs.

[0020] Chisels can be manufactured without machining, particularly by plastic molding, and / or by machining.

[0021] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the invention and from the claims, with reference to the drawings illustrating essential details of the invention. The features shown herein should not necessarily be understood to be to scale, but rather shown in a manner that clearly illustrates the specific features of the present invention. Various features can be implemented individually or collectively in any combination in modifications of the invention.

[0022] Exemplary embodiments of the present invention are shown in the schematic diagrams and will be described in detail in the following description. [Brief explanation of the drawing]

[0023] [Figure 1] This is a diagram of a chisel. [Figure 2] This is a side view of the working section of the chisel. [Figure 3] This is a top view of the working section of the chisel. [Figure 4] It is a cross-sectional view of a chisel. [Figure 5] It is a view showing a further working section of the chisel. [Figure 6] It is a cross-sectional view of the chisel according to FIG. 5. [Figure 7] It is a cross-sectional view of the chisel according to FIG. 5. [Figure 8] It is a cross-sectional view of the chisel according to FIG. 5.

BEST MODE FOR CARRYING OUT THE INVENTION

[0024] In the following description of the drawings, the same or functionally corresponding elements are each assigned the same reference numeral in each case to facilitate understanding of the present invention.

[0025] FIG. 1 shows the chisel 10 in a side view. The chisel 10 is in the form of a flat chisel. It has a working section 12, a shaft section 14, and a striking surface 16. At the free end of the working section 12, the chisel 10 has a cutting edge 18.

[0026] The longitudinal axis L extends through the working section 12, the shaft section 14, and the striking surface 16.

[0027] The chisel 10 can be driven into the base material 20 by the impact of its striking surface 16, for example using a machine tool (not shown in FIG. 1) attached in the region of the striking surface 16. In the example according to FIG. 1, the base material 20 is a mineral base material, for example reinforced concrete.

[0028] In an exemplary embodiment of the chisel 10 shown in FIG. 1, the working section 12 has a plurality of ribs 22. For the sake of simplicity of the explanatory drawing, in FIG. 1, only one of the ribs 22 is provided with a reference numeral.

[0029] Over the life of the chisel 10, the working section 12 normally wears, while the shaft section 14 does not wear or wears only minimally at most.

[0030] A shank 24 is formed on the shaft section 14. In the exemplary embodiment shown in Figure 1, the shank 24 may be designed as a hexagon and / or include such a hexagon. Alternatively, the shank 24 may also correspond to some other standard, for example, a standard commonly called "SDS Plus" or "SDS Max".

[0031] Figure 2 shows a side view of the working section 12 of the chisel 10, and Figure 3 shows a top view.

[0032] The work section 12 has a tip zone 26, an intermediate zone 28, and a transition zone 30.

[0033] In the tip zone 26, the cross-section of the chisel 10 decreases along the longitudinal axis L toward the cutting edge 18.

[0034] The cut edge itself is in the form of a prism and therefore has a non-disappearing, i.e., finite cut edge width s, for example, in the range of 0.5 to 5 cm.

[0035] A total of four ribs 22 are formed in the work section 12. Two of the ribs 22 extend in the form of vertical ribs 32 along the height dimension HD (see Figure 2). Two of the ribs 22 extend in the form of transverse ribs 34 along the width dimension BD (see Figure 3). Thus, they extend along the plane E containing the longitudinal axis L. In the diagram according to Figure 3, plane E extends parallel to the image plane of Figure 3.

[0036] Therefore, the vertical rib 32 extends perpendicular to plane E.

[0037] In this exemplary embodiment, one vertical rib 32 and the other transverse rib 34 are each formed as a pair, mirror images of each other.

[0038] In the intermediate zone 28, the width of the chisel 10 is constant or at least substantially constant, except for localized variations particularly in the rib 22.

[0039] In the transition zone 30, the cross-section is randomly adapted to the adjacent shaft section 14.

[0040] As can be seen particularly with reference to Figure 3, the transverse rib 34 is locally thickened in the rib region 36. In this exemplary embodiment, the rib region 36 is located in the tip zone 26.

[0041] Figure 4 shows a cross-section of the chisel 10 through the working section 12 following the cutting line IV from Figure 3. It can be seen that the vertical rib 32 has a smaller height than the transverse rib 34, which has a height HS measured along the width dimension BD, and in particular a height HH measured along the height dimension HD.

[0042] Figure 5 shows a top view of a further working section 12 of the chisel. This exemplary embodiment also has thickened transverse ribs 34 within the rib region 36. However, in this exemplary embodiment, the rib region 36 is located in the intermediate zone 28. Thus, the rib region 36 is located in a section of the chisel 10 whose overall width is constant or at least substantially constant.

[0043] Figures 6 to 8 show cross-sectional views of the chisel 10 according to exemplary embodiments corresponding to Figure 5, following cutting lines VI, VII, and VIII from Figure 5.

[0044] In the foot region 38, the transverse rib 34 has the same thickness D1 along the cutting lines VI and VIII, as seen in Figures 6 and 8.

[0045] In the foot region 38, the transverse rib 34 has a thickness D2 along the cutting line VII, as shown in Figure 7.

[0046] The thickness D2 along cutting line VII (see Figure 7) is greater than the thickness D1 along cutting lines VI and VIII (see Figures 6 and 8).

[0047] The ellipse inscribed in the cross-section shown in Figure 7 has a cross-sectional area A2. The ellipses inscribed in the cross-sections shown in Figures 6 and 8 each have a cross-sectional area A1. Cross-sectional area A2 is larger than cross-sectional area A1.

[0048] The minimum distance between cutting line VI and cutting line VIII, that is, the minimum distance over which the thickness of the rib, in this case the transverse rib 34, locally increases, may be 5 cm or less. [Explanation of symbols]

[0049] 10 Chisels 12 Work Sections 14 Shaft Section 16 Collision surface 18 Cutting edge 20 Base material 22 Ribs 24 Shank 26. Advanced Zone 28 Intermediate Zone 30 Transition Zones 32 Vertical Ribs 34 Transverse Ribs 36 Rib region 38 Foot area A1 cross-sectional area A2 cross-sectional area BD width dimension D1 Thickness D2 Thickness E plane HD Height Dimensions HH Height HS Height IV cutting line VI cutting line VII Cutting line VIII Cutting line L Longitudinal axis s Cutting edge width

Claims

1. A chisel (10) comprising a working section (12), a shaft section (14), a shank (24), and a longitudinal axis (L) extending through the working section (12), the shaft section (14), and the shank (24), wherein the working section (12) has at least one wedge-shaped cutting edge (18) and a rib (22) extending parallel to or at least substantially parallel to the longitudinal axis (L) and facing radially away from the longitudinal axis (L), The work section (12) tapers toward the cutting edge (18) in two directions (BD, HD) perpendicular to each other. The chisel (10) is characterized in that the rib (22) is locally thickened in at least one rib region (36) and thins towards the cut edge (18).

2. The chisel (10) is characterized in that it has the shape of a flat chisel, as described in claim 1.

3. The chisel according to claim 1 or 2, characterized in that the work section (12) has four ribs (22) formed thereon, which are in particular parallel to or at least substantially parallel to the longitudinal axis (L) and which face radially away from the longitudinal axis (L).

4. The chisel according to claim 3, characterized in that two of the ribs (22) extend in the form of transverse ribs (34) along a plane (E) containing the longitudinal axis (L).

5. The chisel according to claim 4, characterized in that two of the ribs (22) extend in the form of vertical ribs (32) perpendicular to or at least substantially perpendicular to the plane (E).

6. The chisel according to claim 5, characterized in that at least one of the vertical ribs (32) has a height (HH, HS) smaller than that of at least one of the transverse ribs (34).

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