KNIFE AND BLADE

Abstract

The invention relates to a knife, comprising a blade holder and a blade having a blade plane, wherein the blade is arranged in such a way that the blade is retained in the blade holder at two points spaced apart from each other, i.e., a first point and a second point. In order to compensate hardening distortion that occurs when the blade is hardened, according to the invention the blade is retained in a non-displaceable manner at the first point and displaceably in a displacement direction at the second point with respect to the blade plane, wherein the shortest distance of the displacement direction going through the second point from the first point is greater than zero.

Claims

1. A knife comprising: a blade receiving means and a blade having a blade plane, wherein the blade is held in the blade receiving means at two mutually spaced points providing a first point and a second point, wherein the blade is held with respect to the blade plane non-displaceably at the first point and displaceably in a displacement direction at the second, and wherein a shortest spacing of the displacement direction passing through the second point relative to the first point is greater than zero.

2. The knife as set forth in claim 1, wherein the first and second points are spaced from each other with respect to the blade plane at a first spacing parallel to the displacement direction and at a second spacing perpendicular to the second spacing.

3. The knife as set forth in claim 2, wherein the blade is held with respect to the blade plane in a positively locking relationship in the first point and in a positively locking relationship perpendicular to the displacement direction in the second point.

4. The knife as set forth in claim 1, wherein the blade is held at the first and second points by a respective push-in and latching connection.

5. The knife as set forth in claim 1, wherein at the first and second points the blade receiving means has a respective projection which engages through an associated opening provided on the blade.

6. The knife as set forth in claim 5, wherein the opening associated with the second point is in the form of a first slot.

7. The knife as set forth in claim 6, wherein the first slot is of a first diameter (d1) in the displacement direction and a second diameter (d2) transversely relative to the displacement direction and the ratio of the first diameter (d1) to the second diameter (d2) has a value in a range of 1.05d1/d22.0.

8. The knife as set forth in claim 6, wherein the first slot is of an open configuration at an end in opposite relationship to the displacement direction.

9. The knife as set forth in claim 5, wherein the projections are respectively in the form of round pegs and the opening associated with the first point is in a form which is congruent in shape with the peg.

10. The knife as set forth in claim 6, wherein the blade has a second slot having an arrangement and configuration in mirror symmetrical relationship with the first slot with respect to a plane of mirror symmetry which extends perpendicular to the displacement direction and contains the second point.

11. A blade for a knife having a blade receiving means comprising: the blade holdable in the blade receiving means with respect to a blade plane non-displaceably at a first point and displaceably in a displacement direction at a second point and a shortest spacing of the displacement direction relative to the first point is greater than zero, and wherein in the first point the blade has a round first opening and in the second point the blade has an opening which is in a form of a first slot extending longitudinally in the displacement direction.

12. The blade as set forth in claim 11, wherein the first slot is of an opened configuration towards one side in opposite relationship to the displacement direction.

13. The blade as set forth in claim 11, wherein the blade has a second slot which is of an arrangement and configuration in mirror symmetrical relationship with the first slot with respect to a plane of mirror symmetry which extends perpendicular to the displacement direction and contains the second point.

14. The knife as set forth in claim 7, wherein the value of the ratio of the first diameter (d1) to the second diameter (d2) is in a range of 1.1d1/d21.4.

15. The knife as set forth in claim 7, wherein the value of the ratio of the first diameter (d1) to the second diameter (d2) is in a range of 1.15d1/d21.2.

16. The knife as set forth in claim 9, wherein the round pegs are of circular cross-section and the opening of the first point is a circular opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention is described in greater detail herein by means of an embodiment of the knife and the blade illustrated in a drawing in which:

[0034] FIG. 1 shows a plan view of a first embodiment of a knife with blade receiving means and inserted blade, with the blade receiving means being opened;

[0035] FIG. 2 shows an individual view of the blade illustrated in FIG. 1;

[0036] FIG. 3 shows an individual view of the blade receiving means shown in FIG. 1 with peg;

[0037] FIG. 4 shows an individual view of the blade receiving means shown in FIG. 3, but with an additional peg;

[0038] FIG. 5 shows an individual view of the blade shown in FIG. 1 with inserted peg; and

[0039] FIG. 6 shows an individual view of a further embodiment of the blade.

DETAILED DESCRIPTION

[0040] FIG. 1 shows a plan view of a first embodiment of a knife 1 with a blade receiving means 2 and a blade 3. The blade 3 is flat with a blade plane E which is the same as the plane of the drawing in the Figures. Of the knife 1 only the region of the blade receiving means 2 is shown as other regions of the knife 1 are not relevant to the invention. In addition the contour of the blade receiving means 2 is to be taken only by way of example as it can also be of any other configuration. The blade receiving means 2 is shown in the open condition for the sake of clearer illustration. The blade receiving means 2 shown here is formed by two housing halves of which only one housing half 2.1 is shown, being the lower half here, wherein the blade 3 bears in surface contact against the housing halves 2.1 in the blade receiving means 2. FIGS. 2 through 5 show individual views of the blade 3 and the blade receiving means 2.

[0041] The blade 3 is held non-displaceably in the blade receiving means 2 at two mutually spaced points, that is to say, at a first point P1 and a second point P2, with respect to the blade plane E. In this case the blade 3 is held non-displaceably at the first point P1 in relation to the blade plane E and is held displaceably at the second point P2 in a displacement direction v. In regard to the blade plane E in this case the shortest spacing a of the displacement direction v passing through the second point P2, in relation to the first point P1, is greater than zero.

[0042] The points P1, P2 are spaced from each other in relation to the blade plane E at a first spacing a1 parallel to the displacement direction v and at a second spacing a2 perpendicularly to the first spacing a1, the second spacing a2 being equal to the shortest spacing a. The blade 3 is held in the first point P1 in positively locking relationship with respect to the blade plane E and in positively locking relationship in the second point P2 perpendicularly to the displacement direction v and thus in the direction of the second spacing a2. As a result a fixed lever h extending between the two points P1, P2 is formed (see FIGS. 1, 3 and 4), by way of which the blade 3 is held non-displaceably and non-rotatably in the blade receiving means 2. With the first point P1 as a pivot point, by way of the lever h, a lever force F and F respectively is exerted with a force component perpendicularly to the displacement direction v on the blade 3, which presses the blade perpendicularly to the displacement direction v at the inward side against the wall of the slot 5.1 whereby the blade 3 is held non-rotatably in the first point P1.

[0043] At the two points P1 and P2 the blade receiving means 2 of FIGS. 1 and 3 has a respective projection here in the form of a pin or peg 4 of circular cross-section which engages into a corresponding opening 5 of the blade 3, forming a plugging connection, perpendicular to the blade plane E. The opening 5 associated with the first point P1 is of the same cross-section as the peg 4 whereby the blade 3 is fixed in positively locking relationship in the point P1 at the blade receiving means 2. The drawing does not show, although this is provided here, that the pegs 4 engage into a recess provided on the other housing half (not shown here), passing through the openings 5 and forming a plugging connection.

[0044] The opening associated with the second point P2 is in the form of a first slot 5.1 which extends longitudinally in the displacement direction v. It is of a first diameter d1 in the displacement direction v and of a second diameter d2 transversely to the displacement direction v. The difference between the two diameters d1, d2 defines a travel distance over which the blade 3 can be displaced in the displacement direction v relative to the peg 4. Since, as stated hereinbefore, a hardening distortion of the blade 3, that is to be compensated here, is some tenths of a millimeter, the first diameter d1 is only somewhat larger than the second diameter d2, wherein the ratio of the two diameters d1/d2 is here about 1.16, purely by way of example.

[0045] In all embodiments shown here the blade 3 has a second slot 5.2 which is of an arrangement and configuration in mirror symmetrical relationship with the first slot 5.1, relative to a plane S of mirror symmetry which extends perpendicularly to the displacement direction v and which contains the second point P2. The second slot 5.2 is in alignment with the first slot and is disposed at double the first spacing al relative to the first slot 5.1.

[0046] In corresponding fashion the blade receiving means 2 of FIG. 4 has at a third point P3 an additional peg 4 which is of a configuration and arrangement in mirror symmetrical relationship with the peg 4 associated with the second point P2, in relation to the plane E of mirror symmetry. In that way the blade 3 is held at three points P1-P3, wherein those points P1-P3 are arranged in an isosceles triangle in relation to the first point P1. That means that the blade 3 is mechanically stably held. Mechanically favorable symmetrical force conditions with two levers h arranged in mirror symmetrical relationship prevail, which levers form a stable force triangle and which act with displacement of the blade 3 synchronously thereon. In the case of hardening distortion which is uniform over the displacement direction v of the blade 3, with shrinkage, the levers h engage into the slots, being displaced from the plane of symmetry E.

[0047] FIG. 5 shows an individual view of the blade 3 with inserted pegs 4, to show in purely qualitative fashion the substantial changes in dimensions as a consequence of hardening distortion, wherein in particular the dimensional changes are shown in greatly exaggerated form for the sake of enhanced clarity, that is to say greater by a multiple than the dimensional changes which actually occur. The original body lines K of the blade 3 and thus the hardening distortion which occurs are shown in broken line. As can be seen from FIG. 6, in relation to the blade plane E, the axial distortion of the blade strip from which the blades are stamped out is markedly greater than the distortion perpendicularly thereto. That axial distortion is completely compensated by the peg 4 engaging in suitably displaced relationship in the displacement direction in the second point P2 into the first slot 5.1 (and, as shown in FIGS. 2 and 4, into the second slot 5.2).

[0048] FIG. 6 shows a further embodiment of the blade 3 in which the two slots 5.1, 5.2 are laterally opened in the displacement direction v and are thus of a slit-like configuration. This embodiment allows easier and more secure insertion of the blade 3 into the blade receiving means 2.

[0049] Going back to FIG. 1, it can be clearly seen therefrom that it is possible, by virtue of the stable hold for the blade 3, for the cutting portion 6 of the blade 3 to be arranged at a first gap b1 in relation to the wall 7 adjacent thereto of the blade receiving means 2. This means that the cutting portion 6 with its cutting edge (which is not specifically shown here) is not to be disadvantageously mechanically loaded by bearing against the wall 7. The blade 3 is also arranged spaced upwardly in relation to the wall 7 adjacent thereto of the blade receiving means at a second gap b2, wherein the two gaps b1, b2 are here about the same in width. That measure makes it possible for certain dimensional tolerances of the blade receiving means and/or the blade transversely relative to the cutting edge to be also compensated without any problem.

LIST OF REFERENCES

[0050] 1 knife [0051] 2 blade receiving means [0052] 2.1 lower housing half [0053] 3 blade [0054] 4 peg [0055] 5 opening [0056] 5.1 first slot [0057] 5.2 second slot [0058] 6 cutting portion [0059] 7 wall [0060] a shortest spacing [0061] a1 first spacing [0062] a2 second spacing [0063] b1 first gap [0064] b2 second gap [0065] d1 first diameter [0066] d2 second diameter [0067] h lever [0068] v displacement direction [0069] E blade plane [0070] K body line [0071] P1 first point [0072] P2 second point [0073] P3 third point