BLADE ASSEMBLY AND KNIFE THEREFOR

20200276721 ยท 2020-09-03

    Inventors

    Cpc classification

    International classification

    Abstract

    The invention relates to a blade assembly (40) comprising a blade support (14) and a blade (17) that can be detachably fastened in the blade support (14), the blade support (14) having a blade seat (16) having a contact face (42) for a first blade face (43), and a second blade face (44) opposite the first blade face (43) being substantially freely accessible, wherein the blade support (14) has a holder (20) for holding the blade (17) in the blade seat (16), comprising first interlocking formation associated with the blade support (14) and second interlocking formation associated with the blade (17) that interlockingly hold the blade (17) at least in a plane parallel to the contact face (42), the interlocking formation being designed such that the blade (17) has a degree of freedom in at least one direction (v.sub.1) in order to be detached from the blade seat (16).

    The special feature consists in that the holder (20) has a latch (30) having at least one bolt that is movable between a bolted position and a released position, engages over a region of the second blade face (44), and locks movement in the direction (v.sub.1) of the degree of freedom.

    Claims

    1. A blade assembly comprising: a blade having first and second blade faces; a blade support in which blade that is detachably fastened and that has a blade seat having a contact face for the first blade face, the second blade face opposite the first blade face being substantially freely accessible: a holder the blade support for holding the blade in the blade seat and having a first interlocking formation on the blade support and a second interlocking formation on the blade that interlockingly holds the blade at least in a plane parallel to the contact face, wherein the interlocking formations being so constructed that the blade has a degree of freedom in at least one direction in order to be detached from the blade seat; and a latch on the holder and having at least one bolt movable between a bolted position and a released position and engaging over a region of the second blade face or a blade cover to block movement of the blade in the direction of the degree of freedom.

    2. The blade assembly, according to claim 1, wherein the first interlocking formation and the second interlocking formation are designed such that the blade has only one degree of freedom in a pivoting direction.

    3. The blade assembly, according to claim 1, wherein one of the interlocking formations is a projection and the other interlocking formation is a complementary cut-out, whereby the blade is locked in the seat by engagement the projection by into the cut-out.

    4. The blade assembly, according to claim 1, wherein the first interlocking formation comprise at least one hook-shaped projection that detachably engages through a cut-out of the blade, the shape of the cut-out approximately corresponding to a cross section of the hook-shaped projection.

    5. The blade assembly, according to claim 4, wherein the blade is detachably gripped between a holding surface of the projection facing the second blade face and the contact face of the blade support.

    6. The blade assembly, according to claim 1, wherein the bolt is a wire or plate.

    7. The blade assembly, according to claim 1, wherein the movable bolt is a spring.

    8. The blade assembly, according to claim 1, wherein the bolt forms a bolt region and a bearing region.

    9. The blade assembly, according to claim 1, wherein the bolt can be detachably brought into engagement with a seat on the blade support.

    10. The blade assembly, according to claim 9, wherein the seat is provided with an oblique surface that deflects a force, which acts on the bolt element in a first direction, in a second direction orthogonal to the second blade face.

    11. The blade assembly, according to claim 1, wherein the bolt engages through a cut-out of the blade and is in contact with an edge region of the second blade face adjacent to the cut-out.

    12. The blade assembly, according to claim 1, wherein the blade assembly has a blade support and a blade cover.

    13. The blade assembly, according to claim 1, wherein the blade cover is pivotally mounted on the blade support.

    14. A knife having a blade assembly according to claim 1.

    Description

    BRIEF DESCRIPTION OF THE DRAWING

    [0023] In the drawings:

    [0024] FIG. 1 is a side view of a knife in the stowed position,

    [0025] FIG. 2 is a side view of the knife in an operating position,

    [0026] FIG. 3 is a side view of the knife in a blade-changing position,

    [0027] FIG. 4 is a side view of a blade assembly of the knife, having a blade support and a blade retained thereon, a latch being in a bolted position,

    [0028] FIG. 5 is a sectional view along sectional line A-A in FIG. 4,

    [0029] FIG. 6a is a detail according to detail line C in FIG. 5,

    [0030] FIG. 6b is a detail according to detail line D in FIG. 5,

    [0031] FIG. 7a is a view from the direction of the arrow B in FIG. 4,

    [0032] FIG. 7b is a section taken along section line G-G of FIG. 7a;

    [0033] FIG. 8 is an oblique perspective rear view of the blade support according to FIG. 4,

    [0034] FIG. 9 is an oblique perspective front view of the blade support according to FIG. 4,

    [0035] FIG. 10 is a side view of the blade support according to FIG. 4, a latch being in the released position,

    [0036] FIG. 11 is a view from the direction of the arrow E in FIG. 10,

    [0037] FIG. 12 is a view from the direction of the arrow F in FIG. 10,

    [0038] FIG. 13 is an oblique perspective rear view of the blade support according to FIG. 10,

    [0039] FIGS. 14a to 14d show the method for mounting the blade on the blade support,

    [0040] FIG. 15 is an exploded view of the blade support,

    [0041] FIG. 16 is an exploded view of a second embodiment of the blade support,

    [0042] FIG. 17 is a perspective view of the blade support, the latch being in a bolted position,

    [0043] FIG. 18 is a perspective view of the blade support, the latch being in the released position,

    [0044] FIG. 19 is a perspective view of the blade support, the latch being in the released position,

    [0045] FIG. 20 is a side view of the blade support in the bolted position of the latch,

    [0046] FIG. 21 is a sectional view along sectional line F-F in FIG. 20,

    [0047] FIG. 22 is a view from the direction of the arrow G in FIG. 20.

    SPECIFIC DESCRIPTION OF THE INVENTION

    [0048] The knife as a whole according to FIG. 1 is denoted by reference sign 10 in the drawings.

    [0049] The knife 10 comprises a first part 11 and a second part 12. The first part 11 and the second part 12 are part of a mechanism 13 that can move a blade assembly 40 having a blade support 14 and a blade 17, can be moved between a stowed position and an operating position. The stowed position is shown in FIG. 1. Owing to movement of the second part 12 in the direction u.sub.1 about a pivot axis a.sub.1 relative to the first part 11, the blade support 14 can be pivoted from the stowed position into an operating position. The operating position is shown in FIG. 2. The second part 12 can be moved relative to the first part 11 in the direction u.sub.2 out of the stowed position according to FIG. 1, the knife 10 being moved into a blade-changing position according to FIG. 3. In the blade-changing position, the blade support 14 is accessible and the blade can be changed.

    [0050] According to FIG. 4, the blade support 14 has a rear projection 15 for articulated support on the mechanism 13. In order to form the pivot joints, the projection 15 has openings 19a and 19b. In addition, the blade support 14 has a blade seat 16 for fastening a blade 17 that is provided with a cutting edge 18, and a first blade face 43 and a second blade face 44 opposite the first blade face 43. A latch 30 detachably secures the blade 17 to the blade support 14. Projections 21 and 22 are retained on the blade support 14 that, in the present embodiment, are cut out from the blade support 14 and project out of a plane E of the blade seat that has an x/z direction, such that they have a region projecting in the direction y.sub.1 and a region that is parallel to the plane E. The projections 21 and 22 engage through cut-outs 23 and 24 in the blade 17. The projection 22 forms a seat 45.

    [0051] A region 31 of the projection 21 extending in parallel with the plane E has a width K1 that is greater than the width K2 of the opening 23. The cross section of the projection 21 approximately corresponds to the dimensions of the cut-out 23 in the x direction and z direction, or is slightly smaller. For this reason, the blade 17 cannot readily be detached from the projection 21 in the direction y.sub.1. Instead, a pivoting movement of the blade in the direction v.sub.1 according to FIG. 5 is required. The cut-out 24 in the blade is formed such that the blade 17 can be moved away over the region 32 of the projection 22 when pivoting in the direction v.sub.1. The pivoting guidance is predetermined by the shape of the projection 21.

    [0052] A bolt that prevents movement of the blade 17 in the direction v.sub.1 is arranged between a holding surface 33 of the projection 22 and the outer surface 44 of the blade 17 (see FIG. 4). In the present embodiment, the bolt is formed by a leg 27 of a spring 25, the other leg 26 of which is pivotally retained in a bearing device 35 of the blade support 14.

    [0053] In the present embodiment, the bearing device 35 has a projection 36 of the blade support 14 (see e.g. FIG. 8), from which two arms 29a and 29b project in the direction y.sub.1. An opening 37a is formed in the arm 29a and an opening 37b is formed in the arm 29b. The openings 37a and 37b align with one another. The leg 26 engages through the openings 37a and 37b, such that a pivot axis a2 is formed, about which the spring 25 can be pivoted. An end region 38 of the leg 26 is approximately bent at right angles to the longitudinal extension of the leg 26 such that the spring 25 cannot be detached from the bearing device 35. A wound central region 39 of the spring 25 prevents movement of the spring in the direction x by the contact with the arm 29a.

    [0054] An end region 41 of the spring leg 27 is bent such that it can be easily grasped, making it easy for the user to actuate.

    [0055] The spring leg 27 is subjected to pretension about a pivot axis a.sub.3 of the spring 25 in the direction w1 in engagement with the projection 22. Owing to movement of the leg 27 counter to the spring force in the direction w2 and subsequent pivoting about the pivot axis a2 in the direction p1 into the position shown in FIGS. 10 to 13, the locking can be released such that the blade 17 can be removed from the blade seat 16.

    [0056] In the unlocked position according to FIGS. 10 to 13, the blade 17 only has one degree of freedom in the pivoting direction v.sub.1. The blade can then be removed from the blade seat 16 by pivoting in the direction v.sub.1 and can optionally be replaced with another blade 17.

    [0057] The blade 17 can be mounted again by, according to FIG. 14a, the cut-out 23 being brought into engagement with the projection 21 and the blade 17 then being pivoted onto the projection 21 in the direction v.sub.2 (see FIGS. 14b and 14c) until the projection 22 engages through the cut-out 24 and the first blade face 43 comes into contact with the contact face 42.

    [0058] The leg 27 of the spring 25 is then pivoted about the axis a2 in the direction p2 and latches in the seat 45 of the projection 22 by the leg 27 being pivoted somewhat counter to the force of the spring 25 in the direction w2 and then being inserted into the seat 45 in the direction w1.

    [0059] The holder 20 according to the invention having the latch 30 is not vulnerable to dirt, since there are barely any structural design aspects, such as undercuts, angles, etc., that promote the accumulation of particles.

    [0060] A second embodiment of a blade assembly 140 is shown in FIGS. 16 to 22. Since the knife can be designed in substantially the same way as the first embodiment, except for the blade assembly 140, the remaining parts are not described.

    [0061] The blade assembly 140 has a blade support 114 and a blade cover 129. A central longitudinal axis of the blade assembly 140 is denoted by m. The blade support 114 and the blade cover 129 are parts of a holder 120 for a blade 117. According to FIG. 16, the blade support 114 has a rear projection 115 on which bearing pins 119a and 119b are formed. The blade support 114 is provided with a blade 116, comprising a contact face 142 of the blade support 114. Pins 121 and 122 project from the blade support 114. The pin 121 has a notch 136. A bearing region 137 of the blade support 114 is provided for pivotally mounting the blade cover 129.

    [0062] The blade 117 has a cutting edge 118 and two cut-outs 123 and 124. The blade 117 is e.g. designed as a strip steel blade or ceramic blade. A blade face 143 of the blade 117 interacts with the contact face 142 and a blade face 144 of the blade 117 interacts with a contact face 141 of the blade cover 129 when the blade 117 is in the bolted position in the blade seat 116.

    [0063] A spring 125 that is designed as a torsion spring in the present example, is part of a latch 130. It has two end regions 126 and 127. The spring 125 is mounted on the blade assembly 140 by a bearing device 135. Here, a bearing region 128 that is designed as a bearing pin 131 and is arranged coaxially with the wound region of the torsion spring is provided on the blade cover 129. The end region 127 is supported on a stop 132 of the blade cover 129 under pretension. The blade cover 129 also has a projection 133 having a link 134 that is in the form of an opening in the projection 133 here and is provided for restricting the movement of the end region 127 of the spring 125. The link could, however, alternatively be omitted.

    [0064] The blade cover 129 forms a contact face 141 that is shown in FIG. 22.

    [0065] When a blade 117 is mounted in the blade seat 116 such that the blade face 143 abuts the contact face 142, and the projection 121 engages through the cut-out 123 and the projection 122 engages through the cut-out 124, the blade cover 129 can be pivoted in a direction o.sub.2 out of the open position according to FIGS. 18 and 19 about a pivot axis a.sub.4 into the closed position according to FIGS. 17 and 20 to 22 which the projection 121 engages through a cut-out 138 in the blade cover 129. Owing to the pretension of the spring 125, the end region 127 abuts an upper end region 139 of the link 134. The end region of the link 134 opposite the end region 139 is denoted by 145.

    [0066] By the end region 127 being somewhat deflected in the direction n.sub.1, it can be inserted into the notch 136. The latch 130 is then in the bolted position, i.e. the blade cover 129 is prevented from moving in the direction o.sub.1 into the open position by the end region 127 acting as a bolt. The end region 127 extends over a region of an outer surface 146 of the blade cover 129 and abuts the outer surface 146.

    [0067] The notch 136 is arranged on the projection 121 such that the end region 127 has to be moved counter to spring force in the direction n.sub.1 in order to move it out of the notch 136. In this way, the end region 127 is not inadvertently released from engagement with the notch 136.

    [0068] The notch 136 is designed such that it forms a movement converter, such that the spring force exerted by the end region 127 in the direction n.sub.2 is partially diverted into a force that loads the end region 127 in the direction y.sub.1 (see FIG. 22), such that said region exerts a force on the blade cover 129 in the direction o.sub.2. In this way, the blade 117 is securely retained between the contact faces 142 and 141 and blades 117 having different thicknesses D can be securely fastened in the blade seat 116.