Messer

Abstract

Knife (10) comprising a first gear part (11) and a second gear part (12) which is mounted so as to be movable relative to the first gear part (11), wherein the blade device (16) or the blade guard is actuated by the relative movement of the first gear part (11) to the second gear part (12), with a housing formed by the first gear part, with a blade device (16) comprising a blade (23) with at least one cutting edge (35), wherein the blade device (16) and / or a blade guard is displaceable relative to the housing between at least one rest position, in which the cutting edge (35) is arranged in an inaccessible protective position, and at least one operating position, in which the cutting edge (35) is moved relative to the housing in such a way that a cutting process is possible, wherein the housing has at least one opening (22, 24), characterized in thatthat a front end region (18) of the housing has a first opening (22) through which particles can enter the housing, that a particle flow cross-section of the housing in the direction of particle flow from an inlet region (36) of the particles (34) into an interior (25) at the end region (18) of the housing to an outlet region (37) of the particles (34) remains essentially constant or increases, wherein the opening or a second opening (24) is formed on the underside of the housing through which particles can exit the housing.

Description

[0001] The invention relates to a knife.

[0002] Such a knife is known from EP 2 207 649 A1. The knife comprises a housing and an actuating device by means of which a blade carrier is movable between a safety position, in which a blade held in the blade carrier is arranged relative to the housing in such a way that the user cannot injure themselves, and a cutting position in which the blade protrudes from the housing.

[0003] DE 3 121 400 A1 relates to a knife with a housing in which a slider 10 is movable. The slider has a projection 18 that can be engaged with a hole 22 of a blade 21. The slider 10 has a resilient arm 12, whose notch 16 can be engaged with notches 15 of the housing. To prevent the blade from fluttering during the cutting process, it is tightened by a screw 6.

[0004] DE 82 24 475 U1 describes a knife comprising a housing in which a lever 2 is pivotally mounted about a pivot axis located approximately centrally in the longitudinal direction of the housing. A rear end portion of the lever 2 serves as the actuating element, while a front end portion is designed as a blade carrier. The lever is biased by a torsion spring 14 into a safety position in which the blade is retracted into a receiving space in the housing. Upon actuation, the blade can be moved out of the housing against the spring force.

[0005] GB 2 206 832 A discloses a knife with a housing in which an adjusting element 2 with a snap-off blade is slidably guided. Actuators 3 and 4 of the adjusting element 2 protrude through a slot 27 in the housing, which is provided with recesses in the longitudinal direction. The adjusting element is provided with projections that can be brought into engagement with the recesses.

[0006] By pressing one of the actuators 3, 4, the projections are moved out of the recesses so that the blade can be moved relative to the housing.

[0007] The knife according to US Pat. No. 7,322,110 B2 comprises a housing and a blade carrier, which is movable within the housing between a rear position and a front position. The blade carrier is biased into the rear position by a spring. A handle is pivotally mounted on the housing and interacts with a toggle lever mechanism connected to the blade carrier to move the blade carrier from the rear position to the front position. The blade carrier can be locked to the housing in different cutting positions.

[0008] It has been shown that the functional reliability of state-of-the-art blades that come into contact with easily sticky or adhesive materials, such as powders, during the cutting process is reduced to the point of complete inoperability. Particles enter the interior of the housing, and adhesion of the particles can block the movement of moving parts of the blade.

[0009] The object of the invention was to create a knife which is designed in such a way that particles which enter the housing can be expelled from the housing again.

[0010] The problem was initially solved by a knife having the features of claim 1.

[0011] The knife comprises a housing with a blade device. The blade device has at least one blade provided with a cutting edge. For example, the blade device has a blade holder with a blade with a cutting edge held therein. The blade device or a blade guard is mounted displaceably relative to the housing between a rest position and at least one operating position. The housing has at least one opening.

[0012] A particle flow cross-section of the housing in the flow direction of the particles from an inlet opening of the particles at a front end region of the housing to an outlet opening of the particles at a rear end region or at a bottom of the housing remains substantially constant or increases.

[0013] Tests have shown that in this way the accumulation of particles in the housing can be significantly reduced and that a high level of functional reliability can be achieved even with problematic cutting materials, such as bags containing hydrophilic powders that tend to stick together.

[0014] One embodiment is characterized in that the distance between opposing surfaces and the inner walls forming the flow cross-section is substantially constant or increases. For example, opposing side surfaces of the housing-like first transmission part have a constant or increasing distance.

[0015] One embodiment is characterized by the housing's inner wall having flat surfaces or surfaces curved along a radius. This prevents particles from adhering to the housing's inner wall, as angles or gussets promote particle adhesion.

[0016] In principle, it is possible for the first gear part to be pivotable or displaceable relative to the second gear part.

[0017] The knife comprises, for example, a first gear part and a second gear part, which is mounted so as to be movable relative to the first gear part, whereby actuation of the blade device or the blade guard occurs due to the relative movement of the first gear part to the second gear part. A pivoting bearing of the first gear part relative to the second gear part has advantages over a sliding bearing because the construction can be designed with fewer sliding surfaces in contact.

[0018] In the operating position, for example, the second gear part is spaced apart from the first gear part over a substantial part of the longitudinal extent of the outlet opening in such a way that the opening is not closed by the second gear part, ie, the particle outlet is impeded.

[0019] One embodiment is characterized in that the blade device forms a coupling mechanism with a first linkage and a second linkage, and with the first gear part and / or the second gear part. With a coupling mechanism, it is possible to mount the blade carrier exclusively with pivot joints, thus largely avoiding large sliding surfaces, which have lower functional reliability when particles accumulate.

[0020] For example, the blade unit or the blade guard forms a four-bar linkage with a first linkage and a second linkage and with the first gear part and / or the second gear part.

[0021] In the rest position, the blade is moved, for example, into the interior of a housing formed by the first gear part and / or the second gear part in such a way that a user cannot come into contact with the cutting edge. In the operating position, the blade protrudes from an opening in the housing. Within the meaning of the invention, the term "housing" does not necessarily have to be a full-surface enclosure, but can also be, for example, a grid that prevents contact with the cutting edge of the blade.

[0022] Alternatively, in the rest position the blade guard is moved over the blade in such a way that a user cannot come into contact with the cutting edge and in the operating position the cutting edge is freely accessible.

[0023] An embodiment of the invention is characterized in that the housing comprises a front end region, a rear end region, opposite sides, a top side and a bottom side, and that an opening is formed at least on the bottom side through which particles can escape from the housing.

[0024] The outlet opening through which the particles exit the housing extends at least over a housing longitudinal region, which includes the range of motion of movable gear parts that support the blade device. If particles come into contact with movable gear parts beyond the contact with the blade device, they can easily escape from the interior of the housing-like first gear part. For example, the opening extends from a joint between the first gear part and the second gear part to a rear end region of the blade. In this case, a large portion of the particles can leave the interior before contact with the parts supporting the blade device.

[0025] According to a second aspect of the invention, the object is achieved by a knife having the features of claim 12.

[0026] The knife comprises a housing with a blade device. The blade device has at least one blade provided with a cutting edge. For example, the blade device has a blade holder with a blade held therein. The blade device or a blade guard is mounted displaceably relative to the housing between a rest position and at least one operating position. The housing has at least one opening.

[0027] The opening through which the particles escape from the housing extends, for example, over at least a longitudinal portion of the housing, which includes the movement range of the movable gear parts that support the blade device. If particles come into contact with movable gear parts beyond the blade device, they can easily escape from the interior of the housing-like first gear part.

[0028] For example, the opening extends from a joint between the first gear part and the second gear part to a rear end area of ​​the blade. In this case, a large portion of the particles can escape the interior before contacting the parts supporting the blade assembly.

[0029] An embodiment of the invention is described by way of example in the following description of the figures, also with reference to the schematic drawings. For the sake of clarity, identical or comparable parts, elements, or regions are designated by identical reference numerals, sometimes with the addition of lowercase letters, even where different embodiments are concerned.

[0030] Features that are described, illustrated or disclosed only with reference to one embodiment may also be provided in any other embodiment of the invention within the scope of the invention.

[0031] They show: Fig. 1 a side view of the knife in the rest position, Fig. 2 a sectional view according to section line AA in Fig. 1, Fig. 3a a side view of the knife in the operating position, Fig. 3b a view of the knife according to view arrow H in Fig. 3a, Fig. 3c a sectional view of the knife according to section line D - D in Fig. 3a, Fig. 4 a sectional view according to section line BB in Fig. 3a, Fig. 5 a side view of the knife in the operating position according to Fig. 3, Fig. 6 a sectional view according to section line CC in Fig. 5, Fig. 7 a perspective view of the knife in the operating position from an angle from the front, Fig. 8 a perspective view of the knife in the rest position from an angle from the front, Fig. 9 is a side view of the knife in the operating position, with parts of the gear including the blade device not shown for the sake of clarity, Fig. 10 a sectional view according to section line E - E in Fig. 9, Fig. 11 a sectional view according to section line F - F in Fig. 9, Fig. 12 a sectional view along section line G - G in Fig. 9, Fig. 13 a perspective view of the knife, Fig. 14 a view according to view arrow K in Fig. 3a, Fig. 15 a sectional view according to section line I - I in Fig. 14. Fig. 16 a perspective view of the knife from the front, with an upper part of the knife cut away.

[0032] The knife as a whole is designated by reference number 10 in the figures.

[0033] The direction x1 points forward relative to a longitudinal axis m of the blade 10, the direction x2 points backward, the direction z1 points upward, and the direction z2 points downward. The direction y1 points to the left relative to a longitudinal axis m of the blade 10, and the direction y2 points to the right.

[0034] The knife 10 comprises a housing-like first gear part 11 and a second gear part 12. The first gear part 11 and the second gear part 12 form a pivot joint G1, so that the knife 10 can be moved from the Fig. 1 shown resting position into a Fig. 3a when the second gear part 12 is pivoted in the direction u1 relative to the first gear part 11.

[0035] The gear parts 11 and 12 are parts of a gear 13, which further comprises a rocker 14 and a rocker 15, each of which forms a pivot joint with the second gear part 12 and, in addition, each of which forms a pivot joint with a blade device 16. The rockers 14 and 15, the second gear part 12, and the blade device 16 thus form a coupling gear 30. A support 17 forms a joint with the rocker 15 and a joint with the first gear part 11.

[0036] When the gear 13 moves from the rest position to the operating position, a spring is tensioned, which loads the gear 13 into the rest position. If the user relieves the load on the first gear part 11 and the second gear part 12, the gear 13 automatically moves to the rest position according to Fig. 1. The second gear part 12 is also pivoted in the direction u2 relative to the first gear part 11.

[0037] The first gear part 11 comprises a front end region 18, a rear end region 19, a top side 20, and a bottom side 21. The front end region 18 is provided with an opening 22 through which a blade 23 with a cutting edge 35 can emerge from the housing-like first gear part 11. Furthermore, the bottom side 21 is provided with an opening 24 that extends approximately from the joint G1 to the rear end region 19. In the present embodiment, the openings 22 and 24 are separated only by an axle element 33, which is part of the joint G1.

[0038] The first gear part 11 is U-shaped in cross-section, with an interior space 25 of the first gear part 11 being formed between side walls 26a and 26b. The side walls 26a and 26b are provided with a greater height H1 in a front region of the knife 10, in which the blade 23 is in the rest position, than in a rear region of the first gear part 11, in which they have a height H2.

[0039] During the movement between the rest position and the operating position, an actuating force is transmitted to the rocker 15 via the support 17, so that the coupling gear 30 assumes a position in the operating position in which a blade 23 protrudes at least partially from the interior 25 of the first gear part 11 through the opening 22.

[0040] During cutting processes, particles 34, which could impair the function of the knife 10 if they accumulate in large quantities in the interior space 25, essentially enter the interior space 25 through the opening 22, e.g., because particles 34 adhere to side surfaces 27a and 27b of the blade 23 and are carried into the interior space 25 when the knife 10 moves into the rest position. The entry of the particles 34 into the interior space 25 is schematically illustrated in the figures by arrows 36, and the exit of the particles 34 from the interior space 25 is illustrated schematically in the figures by arrows 37.

[0041] In the Fig. 2 and Fig. 4 shows that the side walls 26a and 26b at the front end region 18 taper toward the side surfaces 27a and 27b of the blade 23. This prevents large particles 34 and particle conglomerates from entering the interior 25 during the movement of the knife 10 from the operating position to the rest position. Particles protruding from the side surfaces 27a and 27b are stripped off by the side walls 26a and 26b located close to the side surfaces 27a and 27b.

[0042] However, it cannot be completely prevented that particles 34 enter the interior 25. Particles that have moved into the interior 25 with the blade device 16 can be Fig. 2 escape from the interior 25 in an area 28 of the opening 24, before they reach the movement area of ​​the rockers 14 and 15. The second gear part 12 has in an area 39 (see Fig. 3b), which adjoins the first housing part 11, i.e., is located adjacent to the joint G1, has a smaller width B2 relative to a free end region 38, which is provided with a width B1. For this reason, openings 41a and 41b are formed in the region 39 between the second gear part 12 and the side wall 26a, as well as between the second gear part 12 and the side wall 26b, which form an outlet 37 for the particles 34. Furthermore, the second gear part 12 has an opening 40 directly in the region of the joint G1, which also forms an outlet 37 for particles 34.

[0043] Should particles 34 move into a rear region 31 of the interior space 25, in which the rockers 14 and 15 as well as the support 17 are arranged, they too can easily exit the interior space 25 through the opening 24, since the side walls 26a and 26b in this region only have a height of H2. However, this only affects a very small portion of the particles 34 that have entered the interior space 25, because the majority of the particles 34 already leave the interior space 25 in the region 28 of the opening 24.

[0044] In order to prevent particles 34 in the interior 25 from adhering to an inner surface 29 of the first gear part 11, the inner surface 29 has large radii and avoids sharp angles and gussets in which particles 34 can adhere (see, for example, the Fig. 4, Fig. 10, Fig. 12, Fig. 14 and Fig. 15). As particularly in Fig. 10, the inner surface 29 has exclusively curved or flat areas.

[0045] E.g. in the Fig. 3a and Fig. 7 it can be seen that in the operating position in which the first gear part 11 is pivoted maximally in the direction u1 towards the second gear part 12, a gap 32 is formed between the first gear part 11 and the second gear part 12, which gap allows the unhindered escape of the particles emerging from the opening 24 past the second gear part 12.

Claims

[1] A knife (10) comprising a first gear part (11) and a second gear part (12) which is mounted so as to be movable relative to the first gear part (11), wherein an actuation of the blade device (16) or of the blade guard occurs due to the relative movement of the first gear part (11) to the second gear part (12), with a housing formed by the first gear part, with a blade device (16) comprising a blade (23) with at least one cutting edge (35), wherein the blade device (16) and / or a blade guard is displaceable relative to the housing between at least one rest position, in which the cutting edge (35) is arranged inaccessibly in a protective position, and at least one operating position, in which the cutting edge (35) is moved relative to the housing such that a cutting operation is possible, wherein the housing has at least one opening (22, 24), characterized bythat a front end region (18) of the housing has a first opening (22) through which particles can enter the housing, that a particle flow cross-section of the housing in the flow direction of the particles from an inlet region (36) of the particles (34) into an interior space (25) at the end region (18) of the housing to an outlet region (37) of the particles (34) remains substantially constant or increases, wherein the opening or a second opening (24) through which particles can exit the housing is formed on the underside of the housing. [2] Knife according to claim 1, characterized by that the outlet region is arranged at a rear end region (19) and / or at an underside (21) of the housing. [3] Knife according to claim 1 or 2, characterized by that the distance between opposite surfaces and the inner walls of the housing forming the flow cross-section is essentially constant or increases. [4] Knife according to one of the preceding claims, characterized by that the inner wall of the housing has flat surfaces or surfaces curved in a radius. [5] Knife according to one of the preceding claims, characterized by in that the knife forms a gear (13) and comprises a first gear part (11) and a second gear part (12) which is mounted so as to be movable relative to the first gear part (11), wherein an actuation of the blade device (16) or of the blade guard takes place due to the relative movement of the first gear part (11) to the second gear part (12). [6] Knife according to claim 5, characterized by that in the operating position the second gear part (12) is spaced from the first gear part (11) over a substantial part of the longitudinal extent of the opening (24) such that the opening (24) is not closed by the second gear part (12). [7] Knife according to one of claims 5 or 6, characterized bythat the blade device (16) forms a coupling gear (30) with a first rocker (14) and a second rocker (15) and with the first gear part (11) and / or the second gear part (12). [8] Knife according to claim 7, characterized by that the blade device (16) or the blade guard forms a four-bar linkage with a first rocker (14) and a second rocker (15) and with the first gear part (11) and the second gear part (12). [9] Knife according to one of the preceding claims, characterized by that in the rear end position the blade (23) is moved into the housing in such a way that a user cannot come into contact with the cutting edge and in the front end position the blade (23) protrudes from the opening (22, 24) of the housing. [10] Knife according to one of the preceding claims, characterized bythat in the first end position the blade guard is moved over the blade (23) in such a way that a user cannot come into contact with the cutting edge and in the second end position the cutting edge is freely accessible. [11] Knife according to one of the preceding claims, characterized by that the housing comprises a front end, a rear end, opposing flanks, an upper side (20) and a lower side (21), and that at least on the lower side (21) the opening (22, 24) or a second opening is formed through which particles can escape from the housing. [12] Knife according to the preamble of claim 1, characterized bythat the housing comprises a front end, a rear end, opposing flanks, an upper side (20) and a lower side (21), and that an outlet region (37) formed by an opening (24), through which particles (34) pass out of the housing, is located on the lower side (21), that the blade device (16) forms a coupling mechanism (30) with a first rocker (14) and a second rocker (15) and with the first gear part (11) and / or the second gear part (12), wherein exclusively pivot joints are formed on the housing for mounting the blade device by means of the rockers (14, 15). [13] Knife according to claim 12, characterized by that the exit region (37) through which the particles (34) leave the housing extends at least over a longitudinal region of the housing in which movable gear parts (11, 12) are arranged which actuate the blade unit. [14] Knife according to one of claims 12 or 13, characterized by that the exit region extends from a joint formed by the first gear part (11) and the second gear part (12) to a rear end region (19) of the knife (10). [15] Knife according to one of claims 12 to 14, characterized by that at least in the rest position or in the operating position each area of the opening (24) for the exit of the particles is unlocked. [16] Knife according to one of claims 12 to 15, characterized by that the opening (24) extends over a length of at least one third, in particular half or in particular two-thirds of the total length of the housing, relative to a longitudinal central axis (m) of the housing.

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