CAN OPENER

Abstract

A can opener (1) for opening a can (2) comprises a rotating device (4), a body (5), a traction device (6), a removal device (8) comprising at least one engagement element (9), and a cutting device (7). The traction device (6) is configured to adapt at least a traction device cutting position (tc) and a traction device lifting position (tl). The traction device (6) in the traction device cutting position (tc) and the cutting device (7) are arranged so as to open a can (2). The traction device (6) in the traction device lifting position (tl) and the engagement element (9) in a removal device lifting position (rl) are arranged such as to engage a lid (3) of an opened can (2). An actuation of the removal device (8) t removes an engagement between the traction device (6) and the engagement element (9) with the lid (3).

Claims

1. A can opener for opening a can comprising: a rotating device, a body, a traction device, and a cutting device, wherein the rotating device is rotatably arranged on the body and is configured to rotate about a rotation axis along a first rotation direction and along a second rotation direction running opposite to the first rotation direction, wherein the traction device is arranged on the body and is configured to adapt at least a traction device cutting position upon rotation of the rotating device along the first rotation direction and to adapt a traction device lifting position upon rotation of the rotating device along the second rotation direction, wherein the traction device in the traction device cutting position and the cutting device are arranged so as to open a can, wherein the can opener further comprises a removal device comprising at least one engagement element, wherein the traction device in the traction device lifting position and the engagement element in a removal device lifting position are arranged such as to engage a lid of an opened can, and wherein the can opener is further configured such that an actuation of the removal device transfers the traction device into a traction device release position and the removal device into a removal device release position, whereby an engagement between the traction device and the engagement element with the lid is removed.

2. The can opener according to claim 1, wherein at least one of: i) the engagement element is movably arranged on the body and is movable with respect to the body upon rotation of the rotating device about the rotation axis along the first rotation direction when the removal device is transferred into a removal device cutting position, wherein the engagement element is arranged such as to act on the can to be opened by the traction device in the traction device cutting position and the cutting device; ii) the engagement element is movably arranged on the body and is movable with respect to the body upon rotation of the rotating device about the rotation axis along the second rotation direction when the removal device is transferred into the removal device lifting position; or iii) the engagement element is movable with respect to the body within a plane running perpendicularly to the rotation axis.

3. The can opener according to claim 1, wherein at least one of: i) a lateral distance between the cutting device and the engagement element in the removal device cutting position is larger than a lateral distance between the cutting device and the engagement element in the removal device lifting position; or ii) a lateral distance between the cutting device and the engagement element in the removal device lifting position is smaller than a lateral distance between the cutting device and the engagement element in the removal device release position.

4. The can opener according to claim 1, wherein at least one of: i) a lateral distance between the traction device in the traction device lifting position and the engagement element in the removal device lifting position is smaller than a lateral distance between the traction device in the traction device cutting position and the engagement element in the removal device cutting position; or ii) a lateral distance between the traction device in the traction device lifting position and the engagement element in the removal device lifting position is smaller than a lateral distance between the traction device in the traction device release position and the engagement element in the removal device release position.

5. The can opener according to claim 1, wherein the removal device is swivably arranged on the body and is configured to swivel about a swivelling axis running parallel to the rotation axis.

6. The can opener according to claim 1, wherein the removal device comprises a lever that is operatively connected to the engagement element such, that a swivelling of the lever moves the engagement element with respect to the body.

7. The can opener according to claim 1, further comprising at least one of: i) a removal device biasing means that biases the removal device at least one of a) into the removal device cutting position and b) into the removal device lifting position; or ii) a traction device biasing means that biases the traction device into the traction device release position.

8. The can opener according to claim 1, further comprising an abutment device, wherein at least one of: i) when the traction device is in its traction device release position, the abutment device adapts at least a first abutment position and abuts against the removal device, whereby the removal device remains in its removal device release position; or ii) wherein, upon rotation of the rotating device about the rotation axis along the first rotation direction the abutment device adapts an unblocking position, whereby the removal device is transferable into its removal device cutting position.

9. The can opener according to claim 8, wherein at least one of: i) the abutment device is rotatable about a further rotation axis extending parallel to the rotation axis; or ii) the abutment device is non-displaceable with respect to the body.

10. The can opener according to claim 8, wherein at least one of: i) the abutment device is configured and arranged such, that the traction device is transferable from its traction device lifting position into its traction device release position upon actuation of the removal device; or ii) wherein the abutment device is configured and arranged such, that it adapts a second abutment position when the traction device is in its traction device lifting position, whereby the abutment device prevents the traction device from being transferred into its traction device release position.

11. The can opener according to claim 8, further comprising an abutment device biasing means that biases the abutment device into its abutment position in the absence of a rotation of the rotating device.

12. The can opener according to claim 8, wherein the abutment device comprises a trigger element that is in connection with the traction device when the traction device is in its traction device release position, and wherein at least one of: i) the traction device presses against the trigger element upon rotation of the rotating device along the first rotation direction so as to displace the trigger element, whereby the abutment device is moved out of its abutment with the removal device; or ii) the trigger element abuts against the traction device when the traction device is in its traction device lifting position.

13. The can opener according to claim 1, wherein the removal device comprises an actuating element, and wherein the actuating element is configured and arranged such that, when the traction device is in its traction device lifting position, it presses against the traction device upon actuation of the removal device.

14. The can opener according to claim 1, wherein at least one of: i) the traction device is movably arranged on the body and is movable with respect to the body upon rotation of the rotating device about the rotation axis along at least one of i) the first rotation direction into the traction device cutting position and ii) along the second rotation direction into the traction device lifting position, ii) the traction device is movable with respect to the body within a plane running perpendicularly to the rotation axis, and; or iii) at least one of a) the cutting device is rotatably arranged on the body and is configured to rotate about a further rotation axis or b) the cutting device is non-displaceable with respect to the body.

15. A method of producing a can opener, the method comprising the steps of: providing a rotating device, providing a body, providing a traction device, and providing a cutting device, wherein the rotating device is rotatably arranged on the body and is configured to rotate about a rotation axis along a first rotation direction and along a second rotation direction running opposite to the first rotation direction, wherein the traction device is arranged on the body and is configured to adapt at least a traction device cutting position upon rotation of the rotating device along the first rotation direction and to adapt a traction device lifting position upon rotation of the rotating device along the second rotation direction, wherein the traction device in the traction device cutting position and the cutting device are arranged so as to open a can, wherein the method further comprises the step of providing a removal device comprising at least one engagement element, the traction device in the traction device lifting position and the engagement element in a removal device lifting position are arranged such as to engage a lid of an opened can, and wherein the can opener is further configured such that an actuation of the removal device transfers the traction device into a traction device release position and the removal device into a removal device release position, whereby an engagement between the traction device and the engagement element with the lid is removed.

16. The can opener according to claim 8, wherein the abutment device adapts at least a first abutment position and abuts against the lever, whereby the removal device remains in its removal device release position.

17. The can opener according to claim 11, wherein the abutment device biasing means is attached to the body and the abutment device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Preferred embodiments of the invention are described in the following with reference to the drawings, which are for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same. In the drawings,

[0030] FIG. 1 shows a perspective view of a can opener applied on a can to be opened in a cutting position;

[0031] FIG. 2 shows a perspective view of the can opener according to FIG. 1 in a lifting position lifting a lid of the can;

[0032] FIG. 3 shows an exploded view of the can opener according to FIG. 1;

[0033] FIG. 4 shows a side view of the can opener according to FIG. 1;

[0034] FIG. 5 shows a sectional view of the can opener and the lid according to FIG. 2;

[0035] FIG. 6a shows a bottom view of the can opener in a release position;

[0036] FIG. 6b shows a partial sectional view of the can opener according to FIG. 6a taken on the line indicated by arrow A in FIG. 4;

[0037] FIG. 5c shows a partial sectional view of the can opener according to FIG. 6a taken on the line indicated by arrow B in FIG. 4;

[0038] FIG. 7a shows a bottom view of the can opener in a cutting position;

[0039] FIG. 7b shows a partial sectional view of the can opener according to FIG. 7a taken on the line indicated by arrow A in FIG. 4;

[0040] FIG. 7c shows a partial sectional view of the can opener according to FIG. 7a taken on the line indicated by arrow B in FIG. 4;

[0041] FIG. 8a shows a bottom view of the can opener in a lifting position;

[0042] FIG. 8b shows a partial sectional view of the can opener according to FIG. 8a taken on the line indicated by arrow A in FIG. 4;

[0043] FIG. 8c shows a partial sectional view of the can opener according to FIG. 8a taken on the line indicated by arrow B in FIG. 4;

[0044] FIG. 9a shows a partial view of the can opener according to FIG. 6a;

[0045] FIG. 9b shows a partial view of the can opener according to FIG. 7a;

[0046] FIG. 9c shows a partial view of the can opener according to FIG. 8a.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0047] With respect to the figures various aspects of a can opener 1 for opening a can 2 are discussed.

[0048] In particular, the can opener 1 according to the invention comprises a rotating device 4 in the form of a handle, a body 5; a traction device 6 comprising a serrated traction wheel 22, a cutting device 7 comprising a cutting wheel 25, and a removal device 8. The body 5 is here of an essentially oval shape and defines an upper side 23 and an opposite lower side 24, wherein the rotating device 4 is arranged on the upper side 23 and the traction wheel 22 and the cutting wheel 25 are arranged on the lower side 24, respectively. An elongate grip 26 extends laterally from the body 5, which grip 26 is configured to be graspable by the hand of a user. As best seen in FIG. 1, this configuration allows the can opener 1 to be placed on the top 27 of a can 1 to be opened, wherein the cutting wheel 25 and the traction wheel 22 are facing the top 27 of the can 2, and wherein the rotating handle 4 is facing away from the can 2 and towards an outside. After the can 2 has been opened, the can opener 1 allows a removal of the lid 3 of the opened can 2 as depicted in FIG. 2.

[0049] The can opener 1 can adapt several positions, namely at least a cutting position, a lifting position, and a release position. The cutting position of the can opener 1 is depicted in FIGS. 1, 7a to 7c and 9b. The lifting position of the can opener 1 is depicted in FIGS. 2, 8a to 8c and 9c, The release position of the can opener 1 is depicted in FIGS. 6a to 6c and 9a. In the cutting position of the can opener 1, the can opener 1 is configured to open a can 2. In the lifting position of the can opener 1, the can opener 1 is configured to lift the lid 3 of the opened can 2 away from a can opening. In the release position, the can opener 1 is configured to release the lifted lid 3 from the can opener 1 so that the lid 3 can be disposed, for example. To this end the user does not have to touch the lid 3, instead, the can opener 1 is configured to automatically release the removed lid 3. After the lid 3 has been released from the can opener 1, the can opener 1 can be used to open another can 2. Hence, the release position can also be referred to as an initial position, i.e. the position in which the can opener 1 can be placed on another can 2 to be opened.

[0050] The rotating device 4 is rotatably arranged on the upper side of the body 5 and is configured to rotate about a rotation axis R along a first rotation direction r1 and along a second rotation direction r2 running opposite to the first rotation direction. As best seen in FIG. 3 the traction device 6 further comprises an eccentric 11 that is comprised of an eccentric sheave 12 and a rotating axle 13. The traction wheel 22 is attached on a distal end 28 of the rotating axle 13 and the rotating device 4 is arranged on a proximal end 29 of the rotating axle 13, whereby a rotation of the rotating device 4 is transferable into a displacement of the traction device 6, in particular of the traction wheel 22, with respect to the body 5. A curved elongated hole 10 is provided in the lower side 24 of the body 5, in particular in a plate 30 being inserted into a recess 31 formed in the lower side 24 of the body 5. The traction device 6 is at least partially arranged within said elongated hole 10 and is configured to perform a curved displacement along said elongated hole 10 and thus with respect to the body 5. The cutting device 7 is rotatably arranged on the body 5, in particular on the plate 30 being inserted into the recess 31 in the lower side 24 of the body 5, and is configured to rotate about a further rotation axis R2, which is here arranged slightly inclined with respect to the rotation axis R about which the rotating device 4 rotates. The cutting device 7 is furthermore arranged non-displaceable with respect to the body 5, i.e. it is configured to rotate in situ. The removal device 8 comprises an engagement element 9 and a lever 15. The lever 15 is swivably arranged on the body 5 and is configured to swivel about a swivelling axis S running parallel to the rotation axis R about which the rotating device 4 is rotatable. As best seen in FIGS. 6a to 8c, a free end 32 of the 15 laterally protrudes from the body 5 of the can opener 1. In particular, the lever 15 is arranged within the body 5 and its free end 32 protrudes out of an aperture 33 formed in the body 5. Said free end 32 is graspable by a user and allows an actuation of the removal device 8 that will be explained in greater detail further below. Already at this point it should however be noted that an actuation of the removal device 8 corresponds to a swivelling of the lever 15 about the swivelling axis S.

[0051] The engagement element 9 corresponds here to an essentially cylindrical pin that is arranged within a through-opening 16 of the lever 15 as well as within a curved elongated hole 14 provided in the body 5. Because of this arrangement a swivelling of the lever 15 can be transferred to the engagement element 9, wherein the engagement element 9 travels along the curved elongated hole 14. The displacement performed by the traction device 6 upon rotation of the rotating device 4 takes place within a plane p running perpendicularly to the rotation axis R. Likewise, the swivelling movement of the lever 15 and consequently the displacement of the engagement element 8 takes place within a plane running perpendicularly to the rotation axis R.

[0052] Because the traction device 6 and the removal device 8 are movably arranged on the body 5 these components adapt different positions upon a rotation of the rotating device 4 and/or upon an actuation of the removal device 8. These different positions shall be illustrated by means of FIGS. 6a, 7a and 8a. In fact, the traction device 6 is configured to adapt a traction device cutting position tc upon rotation of the rotating device 4 along the first rotation direction r1 and to adapt a traction device lifting position tl upon rotation of the rotating device 4 along the second rotation direction. Furthermore, the traction device 6 is configured to adapt a traction device release position tr upon actuation of the removal device 8. The traction device release position tr can also be referred to as a traction device initial position. The traction device 6 being in its traction device release position tr is depicted in FIG. 6a. The traction device 6 being in its traction device cutting position tc is depicted in FIG. 7a. The traction device 6 being in its traction device lifting position tl is depicted in FIG. 8a. Likewise, the removal devise 8 is configured to adapt a removal device cutting position rc upon rotation of the rotating device 4 about the rotation axis R along the first rotation direction r1 and to adapt a removal device lifting position rl upon rotation of the rotating device 4 about the rotation axis R along the second rotation direction r2. Furthermore, the removal device 8 is configured to adapt a removal device release position rr upon an actuation of the removal device 8. The removal device release position rl can also be referred to as a removal device initial position. Because the engagement element 9 is operatively connected to the lever 15, the engagement element 9 adapts different positions in accordance with the different positions of the removal device 8, in particular in accordance with different swiveling positions adapted by the lever 15. The removal device 8 being in its removal device release position rr is depicted in FIG. 6a, The removal device 8 being in its removal device cutting position rc is depicted in FIG. 7a. The removal device 8 being in its removal device lifting position rl is depicted in FIG. 8a.

[0053] As best seen in FIG. 3 the can opener 1 further comprises a removal device biasing means 17 that biases the removal device 8 out of its removal device release position rr and thus into the removal device cutting position rc as well as into the removal device lifting position rl. The removal device biasing means 17 corresponds to a leg spring that is connected on one side to the body 5 and on the other side to the lever 15. The can opener 1 also comprises a traction device biasing means 34 that biases the traction device 6 into the traction device release position tr, i.e. into the traction device initial position, and thus out of its traction device cutting position tc as well as out of its traction device lifting position tl. The traction device biasing means 34 likewise corresponds to a leg spring, wherein one end of said spring is connected to the body 5 and the other end of said spring is connected to the traction device 6.

[0054] As follows from FIGS. 3, 6b, 7b and 8b, the can opener 1 further comprises an abutment device 19 and an abutment device biasing means 20. The abutment device 19 is non-displaceably but rotatably arranged on the body 5 and is configured to rotate about a further rotation axis R1 extending parallel to the rotation axis R. The abutment device biasing means 20 biases the abutment device 19 into its abutment position in the absence of a rotation of the rotating device 4 and corresponds here to a spring being attached to the body 5 on one side and to the abutment device 19 on the other side. The abutment device 19 is configured and arranged to act against the removal device biasing means 17.

[0055] In particular, the abutment device 19 is configured to adapt an abutment position and an unblocking position upon rotation of the abutment device 19 about the further rotation axis R1, Namely, the abutment device 19 is configured and arranged such that, when the traction device 6 is in its traction device release position tr, the abutment device 19 adapts its abutment position and abuts against the removal device 8, in particular against the lever 15, whereby the removal device 8 remains in its removal device release position rr. To this end an abutment is established between an abutment surface 35 on the abutment device 19 and a corresponding abutment surface 36 on the removal device 8, in particular on the lever 15. These abutment surfaces 35, 36 are provided here by means of a recess 37 formed in the lever 15 and a projection 38 formed on the abutment device 19 and being receivable in the recess 37 of the lever 15. This situation is depicted in FIG. 6b.

[0056] The abutment device 19 is furthermore configured and arranged such that, upon rotation of the rotating device 4 about the rotation axis R along the first rotation direction r1, the abutment device 19 adapts an unblocking position, whereby the removal device 8 is transferred into its removal device cutting position rc. To this end the engagement between the abutment device 19 and the removal device 8 is released and, due to the biasing force exerted by the removal device biasing means 17, the removal device 8 is transferred from its removal device release position rr into the removal device cutting position rc. This situation is depicted in FIG. 7b. Moreover, and as seen in FIG. 6b, the abutment device 19 comprises a trigger element 21 that is in connection with the traction device 6 when the traction device 6 is in its traction device release position tr. The trigger element 21 corresponds here to a protruding arm that protrudes from the abutment device 19 towards the traction device 6 when the traction device 6 is in its traction device release position tr. In this position the trigger element 21 by the rotating axle 13 of the eccentric 11. Upon rotation of the rotating device 4 along the first rotation direction r1 the traction device 6 is moved along the curved elongated hole 10, wherein the rotating axle 13 presses against the trigger element 21. Because the abutment device 19 is rotatably mounted on the body 5 the pressing force exerted by the rotating axle 13 results in a rotation of the trigger element 21 and, consequently of the abutment device 19, whereby the abutment device 19 is moved out of its abutment with the removal device 8. Because the abutment device 19 can no longer act against the biasing force exerted by the removal device biasing means 17, the removal device 8 is swivelled about the swivelling axis S and is transferred from its removal device release position rr into its removal device cutting position rc, see FIGS. 6b and 7b.

[0057] Moreover, and as follows from FIG. 8b, in the absence of an actuation of the removal device 8 the lever 15 pushes the trigger element 21 into a second abutment position, wherein the trigger element 21 provides an abutment for the traction wheel 22 such that the traction wheel 22 and consequently the traction device 6 is prevented from transferring into the traction device release position tr. In the event that the user actuates the removal device 8 by pushing the lever 15 towards a front side of the can opener, the thus caused swivelling of the removal device 8 allows the abutment device 19 to rotate about its further rotation axis R1 as a consequence of the biasing force exerted by the abutment device biasing means 20. This rotation in turn removes the abutment between the trigger element 21 and the traction wheel 22 such that the traction device 6 is transferred from its traction device lifting position tl into its traction device release position tr by the biasing force exerted by the traction device biasing means 34, see FIG. 8c.

[0058] In order to assist a transfer of the traction device 6 from its traction device lifting position tl into its traction device release position tr the removal device 8 comprises an actuating element 18 in the form of a protruding arm that protrudes from the lever 15 towards the traction device 6, see FIGS. 6b, 7b and 8b. The actuating element 18 is configured and arranged such that, when the traction device 6 is in its traction device lifting position tl, it presses against the traction device 6 upon actuation of the removal device 8. It should be noted that this pressing force is in addition to the spring force being exerted by the traction device biasing means 34.

[0059] When the traction device 6 is in its traction device cutting position tc and the removal device 8 is in its removal device cutting position rc the can opener 1 is in its cutting position, see FIGS. 7a to 7c. As follows from a comparison between FIGS. 6a and 7a, the traction device 6 is moved towards and into proximity with the cutting device 7 upon rotation of the rotating device 4 along the first rotation direction r1. In doing so the traction wheel 22 is brought into proximity with the cutting wheel 25 such that the traction wheel 22 together with the cutting wheel 25 can act on a side wall of the can. If a user continues rotating the rotating device 4 along the first rotation direction r1 the side wall of the can 2 is drawn through a gap being established between the traction wheel 22 and the cutting wheel 25, whereby the side wall of the can 2 is progressively cut until the lid 3 is completely cut off from the can 2. As already explained, the engagement element 9 is displaceably arranged on the body 5 and is moved towards the cutting device 7 upon rotation of the rotating device 4 along the first rotation direction r1 when the removal device 8 is transferred into its removal device cutting position rc. In this position the engagement element 9 presses itself into a cutting edge along which the can 2 is cut by the traction device 6 and the cutting device 7, see FIG. 7a.

[0060] Upon completion of the cutting process, the rotating device 4 is rotated about the rotation axis R along the second rotation direction r2, whereby the can opener 1 is transferred from its cutting position into its lifting position, see FIGS. 8a to 8c. In the process, the traction device 6 and the engagement element 9 are moved away from the cutting device 7, compare FIGS. 7a and 8a. The traction device 6 in the traction device lifting position tl and the engagement element 9 in the removal device lifting position r1 are arranged in proximity to one another so as to engage the lid 3 of the opened can 2. This engagement allows the user to lift the lid 3 from the opened can 2 as it is depicted in FIG. 2.

[0061] Upon actuation of the removal device 8 the traction device 6 is transferred into its traction device release position tr and the removal device 8 is transferred into its removal device release position rr, see FIGS. 6a to 6c. In this release position of the can opener 1 the engagement element 9 and the traction wheel 22 are moved away from one another, compare FIGS. 8a and 6a. In fact, in the release position of the can opener 1 the engagement between the traction wheel 22 and the engagement element 9 with the lid 3 is removed and, consequently, the lid 3 is released from the can opener 1.

[0062] As follows from a comparison between FIGS. 9a to 9c, a lateral distance dc-tc between the cutting device 7, in particular the cutting wheel 25, and the traction device 6, in particular the traction wheel 22, in the traction device cutting position tc is smaller than a lateral distance dc-tl between the cutting device 7 and the traction device 6, in particular the traction wheel 22, in the traction device lifting position tl. Moreover, a lateral distance dc-tl between the cutting device 7 and the traction device 6, in particular the traction wheel 22, in the traction device lifting position tl is smaller than a lateral distance dc-tr between the cutting device 7 and the traction device 6, in particular the traction wheel 22, in the traction device release position tr. A lateral distance dc-rc between the cutting device 7 and the engagement element 9 in the removal device cutting position rc is larger than a lateral distance dc-rl between the cutting device 7 and the engagement element 9 in the removal device lifting position. Additionally, a lateral distance dc-rl between the cutting device 7 and the engagement element 9 in the removal device lifting position rl is smaller than a lateral distance dtc-rr between the cutting device 7 and the engagement element 9 in the removal device release position rr. Furthermore, a lateral distance dtl-rl between the traction device 6, in particular the traction wheel 22, in the traction device lifting position tl and the engagement element 9 in the removal device lifting position rl is smaller than a lateral distance dtc-rc between the traction device 6, in particular the traction wheel 22, in the traction device cutting position tc and the engagement element 9 in the removal device cutting position. Moreover, a lateral distance dtl-rl between the traction device 6, in particular the traction wheel 22, in the traction device lifting position tl and the engagement element 9 in the removal device lifting position rl is smaller than a lateral distance dtr-rr between the traction device 6, in particular the traction wheel 22, in the traction device release position tr and the engagement element 9 in the removal device release position rr. The above-mentioned lateral distances are determined in each case between the respective figurative center points ct, cc, ce of the traction device 6, in particular of the traction wheel 22, the cutting device 7, in particular of the cutting wheel 25, and the engagement element 9, respectively.

TABLE-US-00001 LIST OF REFERENCE SIGNS 1 can opener 2 can 3 lid 4 rotating device 5 body 6 traction device 7 cutting device 8 removal device 9 engagement element 10 hole 11 eccentric 12 eccentric sheave 13 rotating axle 14 hole 15 lever 16 opening 17 biasing means 18 actuating element 19 abutment device 20 biasing means 21 trigger element 22 traction wheel 23 upper side 24 lower side 25 cutting wheel 26 grip 27 top 28 distal end 29 proximal end 30 plate 31 recess 32 free end 33 aperture 34 biasing means 35 abutment surface 36 abutment surface 37 recess 38 projection R rotation axis R1 rotation axis R2 rotation axis r1 first rotation direction r2 second rotation direction S swivelling axis tc cutting position tl lifting position tr release position rc cutting position rl lifting position rr release position dc-rc lateral distance dc-rl lateral distance dc-tr lateral distance dc-rr lateral distance dtc-rc lateral distance dtl-rl lateral distance dtr-rr lateral distance ct center point cc center point ce center point p plane