Abstract
A method of strapping one or more articles with a strap includes the steps of: providing a strapping device including a joining apparatus with a joining jaw and a joining base; placing an end portion of the strap around the joining base such that a fastening loop around the base is formed; joining overlapping first and second strap segments of the fastening loop by the joining apparatus to form a strap joint; placing the strap around one or more articles such that a third strap segment overlaps a segment of the fastening loop; tensioning the strap around the one or more articles; joining the third segment of the strap with the segment of the fastening loop by the joining apparatus; shearing the tensioned strap off from an untensioned bulk portion of the strap; separating the strapping device from the tensioned strap by removing the joining base from the fastening loop.
Claims
1-31. (canceled)
32. A method of strapping one or more articles with a strap, comprising the steps of: providing a strapping device comprising a joining apparatus with a joining jaw and a joining base; placing an end portion of the strap around the joining base such that a fastening loop around the joining base is formed; joining overlapping first and second strap segments of the fastening loop by the joining apparatus to form a strap joint; placing the strap around the one or more articles such that a third strap segment overlaps a segment of the fastening loop; tensioning the strap around the one or more articles; joining the third segment of the strap with the segment of the fastening loop by the joining apparatus; shearing the tensioned strap off from an untensioned bulk portion of the strap; separating the strapping device from the tensioned strap by removing the joining base from the fastening loop.
33. The method according to claim 32, wherein placing an end portion of the strap around the joining base such that a fastening loop around the joining base is formed comprises placing the first strap segment on an upper toothed surface of the joining base and the second strap segment on the first strap segment.
34. The method according to claim 32, wherein a strap portion adjacent to the third strap segment is clamped by a clamp while joining the third segment of the strap and the segment of the fastening loop by the joining apparatus.
35. The method according to claim 32, wherein providing the strapping device comprising a joining apparatus with a joining jaw and a joining base comprises providing an exchangeable joining base.
36. The method according claim 32, wherein providing the strapping device comprising a joining apparatus with a joining jaw and a joining base comprises providing a modular joining base with a base body and a spacer arranged between the base body and the joining jaw and releasably connected to the base body.
37. The method according to claim 32, wherein a blade of a cutter of the strapping device for shearing the tensioned strap off from an untensioned bulk portion of the strap is moved relative to the joining jaw to a retracted inactive position before the step of joining overlapping first and second strap segments of the fastening loop by the joining apparatus to form a strap joint.
38. A strapping device for strapping one or more articles with a strap according to the method of claim 32, the strapping device comprising a joining apparatus with a joining jaw and a joining base, the joining base comprising an upper toothed surface configured to engage with a first strap segment of a fastening loop placed around the joining base.
39. The strapping device according to claim 38, wherein the joining base comprises a base body and a spacer arranged between the base body and the joining jaw and releasably connectable to the base body.
40. The strapping device according to claim 39, wherein the upper toothed surface is arranged at the spacer.
41. The strapping device according to claim 39, wherein the spacer comprises an upper bar and the base body comprises at least one shoulder configured to laterally position the spacer.
42. The strapping device according to claim 41, wherein the base body comprises two shoulders, wherein the upper bar is receivable between the two shoulders.
43. The strapping device according to claim 41, wherein the upper bar is receivable between a shoulder of the base body and a vertical wall portion of the joining apparatus.
44. The strapping device according to claim 41, wherein the upper bar comprises at least one recess which is engageable with the at least one shoulder.
45. The strapping device according to claim 39, wherein the spacer comprises a front leg and a rear leg connected by an upper bar, wherein the front leg, rear leg and upper bar are arranged to form a laterally open arch for receiving the base body.
46. The strapping device according to claim 38, wherein the joining base is releasably mounted at a mounting interface of the strapping device.
47. The strapping device according to claim 38, comprising a cutter for shearing the strap, wherein the cutter comprises a blade which is movable relative to the joining jaw between an advanced active position and a retracted inactive position.
48. The strapping device according to claim 47, wherein the cutter is simultaneously movable with the joining jaw relative to the joining base between an advanced joining position and a retracted strap receiving position.
49. The strapping device according to claim 47, wherein the cutter comprises a follower which is fixedly arranged with respect to the blade and an actuating element with a cam, wherein the actuating element is configured to engage the cam with the follower to move the blade relative to the joining jaw between the advanced active position and the retracted inactive position.
50. The strapping device according to claim 49, comprising a catch configured to lock the actuating element in a raised or lowered position of the blade by engaging with the actuating element.
51. A strapping system comprising the strapping device according to claim 38 and a plurality of spacers with at least one of: different vertical diameters or different upper toothed surface areas.
52. A strapping system comprising the strapping device according to claim 46 and a plurality of joining bases with at least one of: different vertical diameters or different upper toothed surface areas.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0070] The present invention will be explained in more detail, by way of exemplary embodiments, with reference to the schematic drawings, in which:
[0071] FIG. 1a shows an illustration of an embodiment of the invention with a fastening loop placed around a joining base of a strapping device comprising a spacer;
[0072] FIG. 1b shows the strapping device of FIG. 1a without strap;
[0073] FIG. 2a shows an illustration of an embodiment of the invention with a fastening loop placed around an exchangeable joining base of a strapping device;
[0074] FIG. 2b shows the strapping device of FIG. 2a without strap;
[0075] FIG. 3 shows a flow diagram of a sequence of steps of an embodiment of the method of strapping one or more articles with a strap.
[0076] FIG. 4a-b show illustrations of an embodiment of a strapping device in a partial view with a blade of a cutter in an advanced active position and in a retracted inactive position;
[0077] FIG. 5 shows a partial view of the cutter of FIGS. 4a and 4b;
[0078] FIG. 6a-b show vertical cut views of the cutter along the line A-A shown in FIG. 5;
[0079] FIG. 7 shows a semitransparent perspective view of the cutter;
[0080] FIG. 8 shows the strapping device where the joining jaw is moved relative to the joining base into the advanced joining position;
[0081] FIG. 9 shows a perspective partial view of an embodiment of a cutter with a linear cam;
[0082] FIG. 10a-d show the cutter of FIG. 9 with different positions of the actuating element and of the cutter.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0083] For some embodiments in the description of the Figures, same reference numerals may be used for corresponding parts of the embodiments.
[0084] FIG. 1a shows an illustration of an embodiment of the invention in a partial view of a strapping device 1 at the region of the joining apparatus 1.0. The joining apparatus 1.0 comprises a joining jaw 1.1 which, in the shown embodiment, is a welding jaw and a modular joining base 1.2 which is a welding base in the shown embodiment. The welding base 1.2 comprises a base body 1.21 in the form of a base plate and a laterally open, arch-shaped spacer 1.22 receiving the base body 1.21. The base body 1.21 comprises a lateral shoulder 1.211 which engages with a recess 1.221 of the spacer 1.2. The spacer 1.22 is made of metal.
[0085] An end portion 10.4 of a strap 10 is placed around the joining base 1.2 such that a fastening loop 10.5 is formed. Thereby, a first strap segment 10.1 is arranged on an upper surface of the spacer 1.22 and a second strap segment 10.2 is arranged on the first strap segment 10.1 such that the first and second strap segments 10.1, 10.2 overlap. The overlapping first and second strap segments 10.1, 10.2 are joined by the joining apparatus 1.0 to form a strap joint and to secure the fastening loop 10.5. For the purpose of illustration, the first and second strap segments 10.1, 10.2 are separately shown in FIG. 1a and the strap joint is not explicitly indicated. However, the skilled person understands that the strap joint is formed by joining the overlapping portions of the first and second strap segments 10.1, 10.2. The end portion of the strap 10 being fastened to the joining base 1.2, the strap 10 is placed around one or more articles (not shown in FIG. 1a) such that a third strap segment 10.3 is placed above a segment of the fastening loop (or the strap joint, or the first and second strap segments 10.1, 10.2, respectively). After tensioning of the strap 10 around the one or more articles, the third strap segment 10.3 is joined with a segment of the fastening loop by the joining apparatus 1.0. Subsequently, the strap tensioned around the one or more articles is sheared off from an untensioned bulk portion of the strap and the strapping device 1 is separated from the tensioned strap by removing the joining base 1.2 from the fastening loop 10.5.
[0086] Removing of the joining base 1.2 from the fastening loop 10.5 is achieved by moving the strapping device 1 in a direction transverse to the strap axis (e.g. in FIG. 1a into the plane of the drawing). Due to the shoulder 1.211 of the base body 1.21, the spacer 1.22 is removed together with the base body 1.21 from the fastening loop 10.5. The fastening loop 10.5 is closely placed around the joining base 1.2 such that the fastening loop 10.5 lies against the joining base 1.2. However, the tolerance between the fastening loop 10.5 and the joining base 1.2 is sufficient to allow removing of the joining base 1.2 from the fastening loop 10.5.
[0087] FIG. 1b shows the strapping device 1 of FIG. 1a without a strap. The spacer 1.22 comprises an upper toothed surface 1.226 configured to engage with the first strap segment of the fastening loop shown in FIG. 1a. The upper toothed surface 1.226 retains the first strap segment and allows relative movement of the second strap segment with respect to the first strap segment while joining the first and second strap segment to form a strap joint. Further, the upper toothed surface 1.226 retains the fastening loop 10.5 and allows relative movement of the third strap segment with respect to the fastening loop 10.5 such that the third strap segment can be joined with a segment of the fastening loop.
[0088] The spacer 1.22 comprises a front leg 1.222 and a second leg 1.223 which are connected by an upper bar 1.224, such that a laterally open arch receiving the base plate 1.21 is formed. The upper bar 1.224 serves to provide a sufficient height required for the operation of the joining jaw 1.1.
[0089] In a strapping system, spacers with different geometries, e.g. different vertical diameters of the upper bar, and/or different upper toothed surface areas may be used for the strapping device 1.
[0090] The strapping device 1 further comprises a blade apparatus 1.7 for shearing the tensioned strap off from a bulk portion of the strap.
[0091] The strapping device 1 further comprises a positioning pin 1.6 which engages into a recess 1.225 of the spacer 1.22. In some embodiments, the positioning pin may not engage into a recess of the spacer. In some embodiments, the positioning pin may be arranged at a distance to the spacer. In some embodiments, the strapping device may comprise two or more positioning pins. The positioning pin 1.6 serves as guiding element for a strap. The positioning pin 1.6 is retractable in an upward direction, i.e. in a direction away from the spacer 1.22. In particular, the positioning pin 1.6 may be retracted before removing the strapping device 1 from the fastening loop.
[0092] FIG. 2a shows an illustration of an embodiment of the invention in a partial view of a strapping device 2 at the region of the joining apparatus 2.0. The joining apparatus 2.0 comprises a joining jaw (not shown in FIG. 2a) and an exchangeable joining base 2.2. The joining base 2.2 is made of metal.
[0093] An end portion 10.4 of a strap 10 is placed around the joining base 2.2 such that a fastening loop 10.5 is formed. A first strap segment 10.1 is arranged on an upper surface of the joining base 2.2 and a second strap segment 10.2 is arranged on the first strap segment 10.1 such that the first and second strap segments 10.1, 10.2 overlap. The overlapping first and second strap segments 10.1, 10.2 are joined by the joining apparatus 2.0 to form a strap joint and to secure the fastening loop 10.5. Similar to the embodiment shown in FIG. 1a, the first and second strap segments 10.1, 10.2 are separately shown and the strap joint is not explicitly indicated. With the end portion of the strap 10 being fastened to the joining base 2.2, the strap 10 is placed around one or more articles (not shown in FIG. 2a) such that a third strap segment 10.3 is placed on a segment of the fastening loop 10.5 (or the strap joint, or the first and second strap segments 10.1, 10.2, respectively). After tensioning of the strap 10 around the one or more articles, the third strap segment 10.3 is joined with the segment of the fastening loop by the joining apparatus 2.0. Subsequently, the strap tensioned around the one or more articles is sheared off from an untensioned bulk portion of the strap.
[0094] The joining base 2.2 is removed from the fastening loop 10.5 by moving the strapping device 2 in a direction transverse to the strap axis (e.g. for FIG. 2a into the drawing plane). The fastening loop 10.5 is closely placed around the joining base 2.2 such that the fastening loop 10.5 lies against the joining base 2.2. However, the tolerance between the fastening loop 10.5 and the joining base 2.2 is sufficient to allow removing of the joining base 2.2 from the fastening loop 10.5.
[0095] The joining base 2.2 is for example releasably mounted at a mounting interface of the strapping device 2 by a screw joint, such that the joining base 2.2 may be removed from the fastening loop 10.5 together with the strapping device 2 by e.g. a movement transverse to the strap axis, while being releasable from the mounting interface of the strapping device 2 by releasing the screw joint.
[0096] FIG. 2b shows the strapping device 2 of FIG. 2a without a strap. The joining base 2.2 comprises an upper toothed surface 2.21 configured to engage with the first strap segment of the fastening loop shown in FIG. 2a. The upper toothed surface 2.21 is configured to retain the first strap segment and allows relative movement of the second strap segment with respect to the first strap segment while joining the first and second strap segment to form a strap joint. The upper toothed surface 2.21 is further configured to retain the fastening loop and allows relative movement of the third strap segment with respect to the fastening loop while joining the third strap segment with a segment of the fastening loop. The joining base 2.2 is releasably mounted from below at a mounting interface 2.3 of the strapping device 2. In a strapping system, different joining bases with different geometries, e.g. different vertical diameters, and/or different upper toothed surface areas, may be used for the strapping device 2.
[0097] FIG. 3 shows a flow diagram of a sequence of steps of an embodiment of the method of strapping one or more articles with a strap. A strapping device comprising a joining apparatus, for example as shown as in FIG. 1a or 2a, is provided in step S1. In step S2, an end portion of the strap is placed around a joining base of the strapping device such that a fastening loop is formed. In step S3, overlapping first and second strap segments of the fastening loop are joined by the joining apparatus to form a strap joint and to secure the fastening loop. The strap is placed around the one or more articles such that a third strap segment overlaps a segment of the fastening loop in step S4. The strap is tensioned around the one or more articles in step S5. In step S6, the third segment of the strap is joined with the segment of the fastening loop by the joining apparatus. The tensioned strap is sheared off from a bulk portion of the strap in step S7. In step S8, the strapping device is separated from the tensioned strap by removing the joining base from the fastening loop.
[0098] FIGS. 4a and 4b show illustrations of an embodiment of a strapping device 1 in a partial view. The strapping device 1 comprises a cutter 1.4 for shearing the strap with a blade 1.41 which is movable relative to the joining jaw 1.1 in a substantially vertical direction with respect to the joining base 1.2. The joining base 1.2 corresponds to the embodiment as shown in FIG. 11a. The cutter 1.4 is arranged in a rear position next to the joining jaw 1.1 with respect to the longitudinal axis of a strap introduced between the joining jaw 1.1 and the joining base 1.2 (not shown in FIGS. 4a and 4b). The cutter 1.4 may therefore shear a strap at a position next to where overlapping strap portions are joined.
[0099] FIG. 4a shows the blade 1.41 of the cutter 1.4 in an advanced active position whereas FIG. 4b shows the blade 1.41 in a retracted inactive position. In both cases, the cutter 1.4 is shown in a retracted strap receiving position. The cutter 1.4 may be lowered together with the joining jaw 1.1 towards the joining base 1.2 to an advanced joining position. In the advanced joining position of the joining jaw 1.1, the cutter 1.4 may shear a strap while joining overlapping strap portions if the blade 1.41 is in the advanced active position. If the blade 1.41 is in the retracted inactive position, as shown in FIG. 4b, the cutter 1.4 may be lowered together with the joining jaw 1.1 to the advanced joining position without the strap being sheared during a joining operation of the joining jaw 1.1.
[0100] The cutter 1.4 is fixedly connected to the joining jaw 1.1 via the connecting block 1.11 such that the cutter 1.4 as a whole may be movable together with the joining jaw 1.1. The blade 1.41, however, may be movable relative to the joining jaw 1.1 by a rotating actuating element 1.42. The actuating element 1.42 comprises a disc with a lever 1.421 extending from the disc within the plane of the disc. A linearly movable actuating bolt 1.43 is engageable with the lever 1.421 in order to rotate the actuating element 1.42. In FIG. 4b, the actuating bolt 1.43 is advanced compared to the configuration in FIG. 4a and pushes the lever 1.421 such that the actuating element 1.42 is rotated, thereby retracting the blade 1.41 to the retracted inactive position.
[0101] As can be seen in FIG. 4b, the actuating element 1.42 is locked in a raised position of the blade 1.41 by a catch 1.47 engaging with a counter profile of the actuating element 1.42 in the form of a recess 1.422. The catch 1.47 may be disengaged from the recess 1.422 using by a manual or driven handle, e.g. of the tensioning unit of the strapping device 1 (not shown in FIG. 4b), in order to allow the actuating element 1.42 to rotate back to the position shown in FIG. 4a and the blade 1.41 to be advanced to the active position.
[0102] FIG. 5 shows a partial view of the cutter 1.4 of FIGS. 4a and 4b attached to the connecting block 1.11. The cutter 1.4 is connected to the joining jaw via the connecting block 1.11 and thereby movable together with the joining jaw. The blade 1.41 is slidably arranged with respect to the connecting block 1.11. The cutter 1.4 comprises a follower 1.45 which is fixedly arranged with respect to the blade 1.41 and biased against a follower spring 1.44. The follower 1.45 is movable against a bias force of the follower spring 1.44 in a direction to raise the blade 1.41 relative to the connecting block 1.11 and therefore, to the joining jaw. As described above, the actuating element 1.42 may be rotated by pushing and releasing the lever 1.421 by the actuating bolt 1.43.
[0103] FIGS. 6a and 6b show vertical cut views of the cutter 1.4 along the line A-A shown in FIG. 5. The cutter 1.4 comprises a rotating cam 1.46 with a noncircular profile 1.461. The cam 1.46 is supported on a common rotating shaft as the actuating element and configured to be rotatable by the actuating element. Due to the noncircular profile, the cam 1.46 can raise or lower the blade 1.41 by engaging with the follower 1.45 by rotation of the cam 1.46.
[0104] In FIG. 6a, the blade 1.41 is in an advanced active position with respect to the joining jaw and the connecting block 1.11. In FIG. 6b, the actuating element has rotated the cam 1.46 such that the cam 1.46 pushes the follower 1.45 against the bias force of the follower spring 1.44 by means of the noncircular profile 1.461. The follower spring 1.44 is therefore compressed compared to the configuration shown in FIG. 6a.
[0105] By raising the follower 1.45, the blade 1.41 is raised with respect to the joining jaw and the connecting block 1.11 and thus moved from the advanced active position of FIG. 6a into the retracted inactive position of FIG. 6b. By rotating the cam 1.46 back, the follower 1.45 can be lowered by the bias force of follower spring 1.44 and the blade 1.41 moved from the retracted inactive position of FIG. 6b to the advanced active position of FIG. 6a.
[0106] FIG. 7 shows a semitransparent perspective view of the cutter 1.4 with the rotating element 1.42 being locked by the catch 1.47 in a retracted inactive position of the blade 1.41. The actuating element 1.42 is biased against a cam spring 1.462 such that the cam is movable against a bias force of the cam spring 1.462 in a direction to raise the blade 1.41 relative to the joining jaw.
[0107] FIG. 8 shows the strapping device 1 where the joining jaw 1.1 is moved relative to the joining base 1.2 into the advanced joining position. The cutter 1.4 as a whole is also moved together with the joining jaw 1.1 towards the joining base 1.2 due to the fixed connection to the joining jaw 1.1 via the connecting block 1.11. The blade 1.41 is in the advanced active position and may therefore shear a strap while overlapping portions of the strap are being joined between the joining jaw 1.1 and the joining base 1.2. By retracting the blade 1.41 by pushing the actuating bolt 1.43 and rotating the actuating element 1.42, a joining operation of a strap between the joining jaw 1.1 and the joining base 1.2 may be performed without shearing the strap next to the joining jaw 1.1.
[0108] The lever 1.421 of the actuating element 1.42 has a sufficient length to be engageable with the actuating bolt 1.43 also in the advanced joining position of the joining jaw 1.1 where the cutter 1.4 as a whole is being lowered towards the joining base 1.2. The lever 1.421 is therefore configured to be engageable with the actuating bolt 1.43 both in the advanced joining position of the joining jaw 1.1 and the retracted strap receiving position of the joining jaw 1.1.
[0109] FIG. 9 shows a perspective partial view of an embodiment of a cutter 1.4 with a linear cam 1.46. The linear cam 1.46 comprises a ramp 1.461 facing towards the follower 1.45. The ramp 1.461 may engage with the follower 1.45 and raise the blade 1.41 relative to the joining jaw upon linear movement of the cam 1.46 by pushing the follower 1.45 against the bias force of the follower spring 1.44. The actuating element 1.42 has a bar-like shape with the cam 1.46 being arranged at an end of the bar. The actuating element 1.42 and the cam 1.46 are linearly movable in a direction transverse to the longitudinal strap axis or parallel to the cutting edge of the blade 1.41, respectively.
[0110] The actuating element 1.42 comprises a recess 1.422 into which a catch 1.47 may engage in order to lock the actuating element 1.42 in a position where the blade 1.41 is in the advanced active position. Next to the actuating element 1.42, there is arranged a stop element 1.5 with stop surfaces with which a stop pin 1.463 of the actuating element 1.42 can engage to selectively maintain the blade 1.41 in the advanced active position or in the retracted inactive position.
[0111] FIGS. 10a and 10b show the cutter 1.4 with the blade 1.41 in the advanced active position (FIG. 10a) and in the retracted inactive position (FIG. 10b). In FIG. 10a, the catch 1.47 engages the recess 1.422 of the actuating element 1.42 such that the blade 1.41 is locked in the advanced active position. The stop element 1.5 comprises a first stop surface 1.51 and a second stop surface 1.52 with which the stop pin 1.463 of the cam 1.46 may engage, depending on the horizontal position of the actuating element 1.42 and the vertical position of the cutter 1.4. The stop element 1.5 may therefore be spatially fixed with respect to the strapping device and neither move with the joining jaw nor with the cutter 1.4. In FIG. 10b, the catch 1.47 which is supported against a catch spring 1.471 has disengaged from the actuating element 1.42. The actuating element 1.42 is moved in a parallel direction to the cutting edge of the blade 1.41 such that the ramp 1.461 of the cam 1.46 engages with the follower 1.45 and pushed the follower 1.45 against the bias force of the follower spring 1.44, thereby raising the blade 1.41 to the retracted inactive position. The stop pin 1.463 engages with the second stop surface 1.52 of the stop element 1.5 such that the actuating element 1.42 can not be further transversally moved in the direction away from the blade 1.41.
[0112] FIGS. 10c and 10d show the cutter 1.4 with different positions of the actuating element 1.42 where the cutter 1.4 has been moved together with the joining jaw (not shown in FIGS. 10c and 10d) into the advanced joining position. In FIG. 10c, the stop pin 1.463 engages with the second stop surface 1.52 of the stop element 1.5 forming a recess to receive the stop pin 1.463. Due to the engagement of the stop pin 1.463 with the second stop surface 1.52, the blade 1.41 is locked in the retracted inactive position. The joining jaw may therefore execute a joining operation without the strap being sheared by the blade 1.41.
[0113] In FIG. 10d, the stop pin 1.463 engages with the first stop surface 1.51 forming an abutting surface against which 5 the stop pin 1.463 abuts. Due to the engagement of the stop pin 1.463 with the first stop surface 1.51, the blade 1.41 is locked in the advanced active position. The blade 1.41 may therefore shear the strap during a joining operation of the joining jaw.
