EP0999132B1 - Strapping device - Google Patents

Abstract

The banding apparatus includes a clamping device which has a rocker (37) opposite a clamping wheel (30) and turning about a rocker axis (38). The clamping wheel and the rocker can be moved towards each other. The band can be clamped between the rocker and the clamping wheel. The band passes round the clamping wheel for a large angle ( alpha ).

Description

The invention relates to a strapping tool for strapping Packaged goods with a strap, the strapping tool with a a tensioning drive operatively connected tensioning device for Tensioning the tape, a closure device for Closing two ends of a band, and several Backstops to fix the strap in the strapping tool, having.

The invention relates primarily to portable, mobile, i.e. non-stationary and permanently installed, Strapping tools, preferably electrically powered and with an off-grid power supply like for example, an accumulator. at Such devices always have the problem that the - for a given number of times with one battery charge strapping to be carried out - maximum on each strapping applied clamping force through the available relatively low battery capacity is limited. The Ultimately, tension remains in a belt loop is also reduced by the fact that the tape during the Formation and closing of the band loop usually is guided over a base plate with which the Strapping tool on the packaged goods. after the Strap loop is closed, the strapping tool from Packaged goods taken and the base plate from the Ribbon loop pulled. Because this is different from the one already closed strap loop reduces the amount to be strapped, the tension in the band also decreases. But often they are different aspects of Device designs that cause strapping devices the desired efficiency is not achieved.

DE-21 02 344-A is a device for connecting known from tapes of thermoplastic, which has a tension pulley. To make a connection between a lower and an upper end of the band Tension roller on the belt ends lying in a tension bed be lowered. When tensioning, the lower end of the strap is removed from the Fitted bed and the upper end of the belt from the tension roller recorded. The fitted bed can be swiveled around an axis stored and it is with a grub screw in its Adjustable altitude. When adjusting the altitude of the Fitted bed with the grub screw becomes the fitted bed pivoted slightly about the axis mentioned. This However, adjustment only seems to be a fine adjustment of the To affect the fitted bed.

From US-4 015 643-A is a further clamping tool known for connecting two ends of the band. The clamping tool has a feed roller at the bottom of a pivotable arm is attached. Under the feed roller is a gripper pin pivotable about a pivot axis stored, the pivot axis of the gripper pin and the Axis of the feed roller are arranged in parallel. Either the feed roller as well as one of the feed roller facing and concave curved surface of the gripper pin are toothed. Between these two the lower and the upper end of the belt are toothed lie. In use, the feed roller is replaced by a Spring pressed against the gripper pin, whereupon the latter aligns so that the top contact surface of the top End of tape feed roller and lower contact surface of the lower band end the curved surface of the Touch the hook pin evenly. Apparently it is here mainly about the forces that occur evenly distributed to weaken at certain points Avoid band spots.

In particular, US-4 015 643-A shows one Tensioning device, with one opposite the tensioning wheel arranged rocker-like part (gripper plug or Gripper pin) is present. Neither of the two writings basically deals with the problem of Increasing the efficiency of strapping tools.

The invention is therefore based on the object. Strapping tool with the highest possible efficiency or Efficiency, especially with regard to the exploitation of a Accumulator charge, to create. In this regard, under "Efficiency" or "Efficiency" which with a certain achievable number of accumulators Understanding strapping with a certain band tension become. However, this can also be understood as how large when executing a certain number Strapping - when using the full Accumulator partial capacity - maximum achievable per strapping Band tension is.

This object is achieved according to claim 1. With one mentioned at the beginning Strapping tool, especially one from an external one Energy source independent portable strapping tool, supports a preferably without an envelope drive (such as, for example, a V-belt) from an engine - preferably under Interposition of a gearbox - drivable tension wheel during a tension phase against a seesaw. In order to the tape between the seesaw and that as simply as possible Tension wheel is insertable, there should be a distance between the Tension wheel and the rocker can be changed. To do this it is preferred to achieve that the tensioning wheel can be pivoted is stored.

It. has proven to be convenient when the seesaw according to the size and direction of the tension wheel applied pressure can align itself. this leads to particularly good contact conditions between the tensioning wheel and the tape and thus with respect to a good efficiency for strapping with a certain band tension required amount of energy. It can therefore be used with the same total available capacity of one Accumulator more strapping than before common.

A high efficiency contributes particularly that two Arms of the rocker each have a rotatable roller over which the tape to be tensioned is led. The expediently provided with the same diameters Rolls are preferably much smaller than that Tensioning wheel. When tensioning the strap, it should be in each case belt section between the rollers on the tensioning wheel and the two roles. With the two roles a relatively large wrap angle of the band around the tensioning wheel with low friction between the seesaw and the strap are achieved, reducing the risk of band deformation and slip between the band and the Tensioning wheel can be reduced. Both band deformations Slip can also drive the required power increase.

It can also be advantageous if the rocker with a pressure surface is provided on the tape during the tensioning phase from Tension wheel is pressed. The pressure surface can have a curvature have the expedient to the radius of the Tensioning wheel is adjusted, which makes the strap special hugs the tensioning wheel well.

To minimize the loss of already applied To achieve belt tension, it can be provided that a first part of the base plate of the closure device and a second part of the base plate of the clamping device is assigned, and one between the two parts Implementation is formed through which a section of a Strap loop is feasible.

With strapping devices it is usually provided that the clamping, locking and cutting device and Backstops, such as clamping devices support the base plate. That's why the tape is over a comparatively - seen in the direction of the tape - long Base plate guided. Since the base plate after the Closing the strap loop pulled out of this is then leaves the band tension relatively strong to. The invention can deviate from this by the Path length of the belt loop on the base plate is shortened. This can be achieved by using the strap loop only is guided over that part of the base plate on which the Devices are arranged on the strap loop act. In devices according to the invention can therefore preferably be provided that the clamping device - in Seen tension direction - after the locking device is arranged and acts on a band section which is not part of the strap loop. Since the Clamping device also expediently on the Supported by the base plate, the strap loop can be replaced by a Recess of the base plate are passed. The Recess can be between the closure device and a tensioning wheel of the tensioning device. To one such recess between two parts of the base plate can train the two parts of the base plate connected in one piece as well as separate components be the appropriate way to a base plate are composed. With this measure, the path of the Belt loop over the base plate can be shortened, which the loss of tape tension by removing the Strapping device can be reduced from the packaged goods.

Also that of the welding device for welding Two layers of the tape have an impact on the current Efficiency of a strapping tool. According to another Aspect of the invention is therefore intended to be a welding device be created for a strapping tool with which special efficiently that of an energy source for the The welding process uses the energy made available becomes. To achieve an improvement here; can with a Strapping device mentioned at the outset that the Welding device has a lever on one End of an eccentric connected to a motor shaft, for the transmission of a motor shaft eccentric movement on the lever, which attacks other end is operatively connected to a welding shoe, with the lever at one end between its two ends Swivel axis is pivotally mounted so that the movement of the eccentric to an oscillating and essentially straight back and forth movement of the welding shoe. So despite the pivoting movement of the lever, the welding shoe should perform a substantially rectilinear movement a force (directly or indirectly) on the lever, preferably act a spring force that the lever during of the entire welding process or movement sequence in Direction towards the base plate and thus towards it welding tape presses.

In a preferred embodiment of the invention, the Motor arranged on a support against which the lever can only perform rotary swiveling movements. A structurally particularly simple solution arises when the Lever is mounted directly on the carrier.

It is preferred if the eccentric is in a slot-like recess of the lever is arranged, For example, a fork, and against this on two itself essentially diametrically opposite points.

In the case of concretely implemented such embodiments of the Invention has been shown to be special enable low-noise welding.

Another expedient embodiment of the invention can provide that the carrier is pivotable about an axis of rotation is stored and the force to press the welding shoe on the tape over the carrier on the lever in the Welding shoe is initiated.

Improving efficiency can also help when the welding shoe the two to be welded Band layers presses on a counter support. The counter edition should be toothed and can preferably be on the Base plate may be arranged.

In a further embodiment, a strapping tool has at least two backstops with which the tape is fixable. Here, the locking device be arranged between the two backstops. This Arrangement has been found especially for such use cases proven, in which the tape during the tensioning process from the Clamping device from the locking device "pulled out" and not "pushed in". The means it is a constructive structure of a Strapping tool, in which the tensioning device in Clamping direction arranged behind the closure device is. However, it is particularly preferred if a third Backstop is available with which the tensioning wheel can be fixed is. The tensioning wheel should at least counter Rotational movements in the clamping direction can be locked. With this Arrangement, it is possible that by the tensioning process Closure device pulled tape through already applied tape tension for the closure and Fix the cutting process and still that Band section, which is subsequently friction-welded and is cut from the tape tension essentially to relieve again. This has the advantage that the preferably substantially transverse to the longitudinal extent of the Banding movement of the welding shoe better in Can convert heat of the tape, and that when cutting the Plastic tape clean cutting edges arise. Under Tensioned plastic tapes tend to cut to splice.

The invention also relates to one mentioned at the outset Strapping tool with the control functions for backstops via a control board from a hand lever to the Backstops are transmitted. The control board transmits preferably for all existing ones Backstops their control functions. This leaves the number of individual parts decrease, which makes it Weight of the intended as a mobile handset Strapping tool can be reduced. Because everyone Control functions triggered by a central hand lever be, this also the operation of the Strapping tool relieved.

A particularly simple and space-saving design Formation of a strapping device according to the invention provide that the control board with a swivel lever the hand lever is connected. With the control board you can Transmission means, for example axes of rotation connected through which the backstops of one Locked position in an insertion position or vice versa be transferred.

Further preferred configurations of the invention result itself from the dependent claims.

Fig. 1

ein erfindungsgemässes Umreifungsgerät in einer ersten Seitenansicht, wobei sich ein Handhebel in einer ersten Endlage befindet;

Fig. 2

das Umreifungsgerät von Fig. 1 mit einer anderen Stellung eines Handhebels;

Fig. 3

das Umreifungsgerät von Fig. 2 in einer Ansicht von hinten;

Fig. 4

eine Schnittdarstellung einer Drehachse des Umreifungsgerätes;

Fig. 5

ein Spannantrieb des Umreifungsgerätes;

Fig. 6

der Spannantrieb von Fig. 5 während einer Spannphase;

Fig. 7

der Spannaritrieb von Fig. 5 während eines Schweissvorganges;

Fig. 8

eine Schnittdarstellung einer weiteren Drehachse des Umreifungsgerätes;

Fig. 9

eine Rücklaufsperre des Umreifungsgerätes in einer ersten Endlage;

Fig. 10

die Rücklaufsperre von Fig. 9 in einer zweiten Endlage;

Fig. 11

eine Darstellung des Umreifungsgerätes gemäss Fig. 3, wobei sich der Handhebel in einer zweiten Endlage befindet;

Fig. 12

eine Darstellung des Umreifungsgerätes gemäss Fig. 3, wobei sich der Handhebel in einer Zwischenstellung befindet;

Fig. 13

eine Schnittdarstellung entlang der Linie A - A in Fig. 4;

Fig. 14

eine Schnittdarstellung entlang der Linie B - B in Fig. 4;

Fig. 15

eine Schnittdarstellung entlang der Linie C - C in Fig. 4;

Fig. 16

ein Teil einer möglichen - sich in einer Schweissposition befindenden - erfindungsgemässen Schweisseinrichtung in einer teilweise geschnittenen Darstellung. Die Schweisseinrichtung von Fig. 16 unterscheidet sich von der in Fig. 1 stark schematisiert dargestellten Schweisseinrichtung;

Fig. 17

eine Schnittdarstellung gemäss der Linie D-D von Fig. 16;

Fig. 18

die Schweisseinrichtung von Fig. 16 in einer Einführposition.

The invention is explained in more detail with reference to the exemplary embodiments shown schematically in the figures; show it:

Fig. 1

a strapping device according to the invention in a first side view, wherein a hand lever is in a first end position;

Fig. 2

the strapping device of Figure 1 with a different position of a hand lever.

Fig. 3

the strapping device of Figure 2 in a view from behind.

Fig. 4

a sectional view of an axis of rotation of the strapping tool;

Fig. 5

a tension drive of the strapping tool;

Fig. 6

5 during a clamping phase;

Fig. 7

the Spannari drive of Figure 5 during a welding process.

Fig. 8

a sectional view of another axis of rotation of the strapping tool;

Fig. 9

a backstop of the strapping tool in a first end position;

Fig. 10

the backstop of Figure 9 in a second end position.

Fig. 11

an illustration of the strapping device according to FIG 3, wherein the hand lever is in a second end position.

Fig. 12

an illustration of the strapping device according to FIG 3, wherein the hand lever is in an intermediate position.

Fig. 13

a sectional view taken along line A - A in Fig. 4;

Fig. 14

a sectional view taken along line BB in Fig. 4;

Fig. 15

a sectional view taken along the line C - C in Fig. 4;

Fig. 16

a part of a possible welding device according to the invention, which is in a welding position, in a partially sectioned illustration. 16 differs from the welding device shown in a highly schematic manner in FIG. 1;

Fig. 17

a sectional view along the line DD of Fig. 16;

Fig. 18

16 in an insertion position.

1 is a strapping tool according to the invention shown, in the housing 1, a clamping device with a Clamping drive 2, designed as a welding device Closure device 3, a cutting device 4, and three backstops are arranged, of which in Fig. 1st however, only the two backstops 5, 6 can be seen are. The housing 1 has a 'below these components Base plate 7, which is divided into two arms 11, 12. The two arms 11, 12 are spaced apart arranged and open an opening between them. A Contact surface 11a of the arm 11 for the arrangement of the Strapping tool on packaged goods can not in others illustrated embodiments of the invention, concave be curved so that the device can also be used on round packaged goods can be safely arranged.

All functions of the with a battery or a Accumulator 8 provided strapping tool a hand lever 9 triggered by one on the housing 1 stored axis of rotation 10 from a first end position in a second end position is pivotable. As is particularly the case in FIG. 3 is recognizable is a first swivel arm 13 on the axis of rotation 10 rotatably arranged. The swivel arm 13 is also on one plate-shaped and essentially triangular Control board 14 attached to which also a second Swivel arm 15 and a tab 16 are articulated. The tab 16 is provided with a backdrop 17.

4 and 5 show that on an axis of rotation 18 of the second swivel arm 15 is a first double lever 19 located, 'has two lever arms 20, 21. At the ends at least one of the two lever arms 20, 21 is free rotatable roller arranged. In the swivel range of the first Double lever is a lever arm 24 of a second Double lever 25 leading to a third backstop 26th heard. The second double lever 25 is on a pivot axis 27 of the tensioning drive arranged and has a second Lever arm, which is provided with a pawl 28.

The tensioning drive also mounted on the swivel axis 27 2 can by operating the hand lever around the pivot axis 27 are pivoted. The tension drive 2 has a a wave of a not shown DC motor arranged tensioning wheel 30. Coaxial to Tensioning wheel 30 is a ring gear 31 on the same shaft Planetary gear arranged, the circumference with two itself diametrically opposite recesses 35, 36 provided is. The recesses 35, 36 are for engagement of the: pawl 28 the third backstop 26 is provided. Through a such engagement can the ring gear 31 against rotational movements in Locked counterclockwise. Here is too take into account that all information about a sense of rotation of course always on the respective presentation refer in the figures.

The figures do not show that not only that Achieving a reduction of the planetary gear provided to the tensioning wheel 30, but also the DC motor to the two previously mentioned components is arranged coaxially. This arrangement also contributes to the strapping tool to achieve the highest possible efficiency. To the To increase efficiency, the planetary gearbox has three - instead of the usual two for hand strapping tools - Reduction levels.

The second arm 12 of the base plate 7 (Fig. 1) is below the tensioning wheel 30 arranged. In a deepening of the second arm 12 is a rocker 37 which is around a Rocker axis 38 is pivotable (Fig. 5 - 7). The storage of the Rocker 37 is made so that it is about your Rocker axis 38 can rotate freely, which makes them according to the size and direction of the pressure of the band or the tensioning wheel 30 aligns itself. On the ends of two rocker arms of essentially the same length a freely rotatable counter roller 39, 40 is attached, those without a belt of an envelope drive, such as a V-belt, act directly on the strapping. Of those essentially parallel to the rocker axis aligned two axes of the counter rollers 39, 40 is located itself - in relation to the clamping direction (arrow 43) - one Axle or counter roller in front and the other counter roller behind the rocker axis 38. The distances between the axes of the counter rollers 39, 40 to the rocker axis 38 are thus essentially the same large. Furthermore, is in the representations of FIGS. 5-7 to recognize that an imaginary connecting line 41 of an axis of rotation of the tensioning wheel with the rocker axis 38 'in substantially orthogonal to the arm 12 of the base plate is aligned.

The tensioning wheel 30 is pivoted about the Swivel axis 27 in contact against the two rollers 39, 40 brought. The distance between the two counter rollers should therefore be dimensioned such that a sufficiently large Set the wrap angle (α) of the belt on the tensioning wheel (Fig. 6). This means that the Wrap angle should have a size through which a Slip of the tape against the tensioning wheel at least in is essentially avoidable. In the illustrated Embodiment is the distance between the two - compared to: tensioning wheel much smaller - counter rollers 39, 40 in about 70% of the radius of the tensioning wheel. Of course this value may vary depending on, for example, the Pressure force of the tensioning wheel against the seesaw Surface condition and the material of the tensioning wheel, the band type, etc. vary. Finally, due to of the geometric relationships can also be provided that a resulting pressure force of the tensioning wheel against the Rocker 37 does not intersect the rocker axis. This creates Always press the tensioning wheel against the rocker Torque about the rocker axis 38, resulting in a Particularly good alignment of the seesaw with the tensioning wheel can be achieved.

On the same shaft of rocker 37 as that in Tensioning direction (arrow 43) rear counter roller 40 of rocker 37, a pivotable pawl 44 is also mounted. In one in Fig. 5 shown basic position is the pawl 44 in essentially vertically aligned. In this basic position the tensioning wheel 30 is supported only on the pawl 44. As a result, between the tensioning wheel 30 and the counter rollers 39, 40 a gap is formed, into which the - in FIG. 6 shown - to exciting band 45 is insertable. Like Fig. 6 can be removed, the tensioning wheel 30 increases Counterclockwise rotary movements with the pawl 44. This turns it clockwise into another End position in which the tensioning wheel 30 is on the rocker 37 is lowerable. This is the clamping position of the strapping tool, in which on a strap loop 46 Tension is applied. Because the rocker 37 is pivotable is stored, it adjusts itself so that the two counter rollers 39, 40 forces occurring during tensioning can record and derive into the base plate 7.

The front backstop 5 shown in Fig. 1 is - 4 - with a sleeve-shaped section 47 on an eccentric axis 48 stored, which in turn is arranged on the axis of rotation 18. This storage is carried out so that the front or first backstop 5 relative to the axis of rotation 18 relative is rotatable. The backstop 5 is not one shown, acting approximately in the direction of tape tension, spring provided by the backstop 5 on the first arm 11 of the base plate 7 is pressed. The transfer of a Rotary movement takes place by placing one on the eccentric axis arranged driving cam 49, which on a sleeve-shaped section provided driver cams 50 presses (Fig. 4 and 15). Coupling the backstop 5 with the eccentric axis 48 thus takes place through a positive engagement of the two driver cams 49, 50.

At one end of the axis of rotation 18 of the second swivel arm 15 there is also a switching disc 51, which with the Axis of rotation 18 is rotatably connected. The switching disk 51 is with a spring 42 shown in Fig. 3 for Clockwise rotary movements are subjected to force. The Switching disk 51 has claws 54a, 54c on the front side Coupling on (see FIG. 14) through which the switching disc 51st is rotatably connected to the swivel arm 15. For this are in each case the two claws 54a, 54c on one end face of the Switch disc 51 arranged diametrically opposite. Two other claws 54b, 54d are on the swivel arm 15 and are also diametrically opposite. Since one claw each the swivel arm 15 between two claws of the switching disc engages, it occurs at certain rotational positions between the switching disk 51 and the swivel arm 15 a non-rotatable connection in the form of a positive connection Claws. As a result, the swivel arm 15 takes the switching disk 51 with while at other rotational positions Relative movements between the two elements possible are.

Unlike the second swivel arm 15, the double lever 19 mounted rotatably on the eccentric axis 48 and with the second swivel arm 15 by a further claw coupling non-rotatably connected (Fig. 4 and 13). This clutch too has four claws 55a-55d which interlock. Contrary to the claw coupling discussed earlier here the claws 55c, 55d of the double lever 19 to the claws 55a, 55b of the swivel arm 15 no play in the circumferential direction on, which makes it non-rotatable in all rotational positions Connection between the double lever 19 and the swivel arm 15 given is. The rotational position of the double lever 19 on the Eccentric axis 48 is thus on the swivel arm 15 and the Control board 14 determined by the hand lever 9. The respective Position of the hand lever 9 also has a corresponding one Position of the eccentric axis 48 relative to the axis of rotation 18 Sequence (Fig. 3 and 4).

The second backstop 6 is through a second axis of rotation 56 actuated, which is mounted on the housing 1 (Fig. 1 and 8). For this purpose, a sleeve-shaped locking lever 58 is the second Backstop 6 on a second eccentric axis 57 arranged, which is eccentric with respect to the axis of rotation 56 is aligned. The eccentric axis 57 is with the axis of rotation 56 connected in one piece. The locking lever 58 and the Eccentric axis 57 are by creating a nose 58a of the Locking lever 58 on a driver 57a of the eccentric axis 57 in certain rotational positions of the axis of rotation 56 rotatably connectable to each other (Fig. 8 - 10). 9 is one non-rotatable connection and in Fig. 10 a constellation shown, in which no slewing ring between the Locking lever 58 and the eccentric axis 57.

On the axis of rotation 56 there is also a sleeve is designed as a ratchet lever 59. One of two arms 60, 61 of the ratchet lever 59 is in the backdrop 17 of the Control board 14 pivotally hinged tab 16 out (Fig. 3). On the other arm 61 of the ratchet lever 59 can a rotatable pawl 64 act and in a locked position the ratchet lever 59 against rotational movements in Lock counterclockwise. For this purpose, the arm 61 of the Pawl lever 59 attached a tension spring 62 with which the arm 61 is pressed against a pawl 64. Jack 64 in turn can by a nose 65 of the control board 14 their locked position can be rotated, causing the latch lever 59 is movable in both directions of rotation.

A movement triggered by the hand lever 9 Control board 14 leads, among other things. to a rotational movement of the second axis of rotation 56, whereby the locking lever 58 one for Axis of rotation 56 performs eccentric pivoting movement (FIG. 1, 3 and 8). Through this pivoting movement, a Locking lever 58 articulated locking plate 66 on a Bevel 67 of the first arm 11 of the base plate 7 is pressed on or be lifted off again (Fig. 9 and 10). So that a toothed pressure surface 68 of the locking plate 66 at the first contact with the slope 67 at least in is aligned approximately parallel to this Locking plate 66 loaded with a tension spring 69. Furthermore is the rotary movement caused by the tension spring 69 by limited a nose 70 of the locking plate that with the Locking lever 58 comes into contact when the locking plate 66 of the slopes are lifted.

So that the locking plate 66 when lowering towards and Base plate experiences the greatest possible acceleration and after operating the hand lever 9, the tape with a high Clamping force quickly sticks, the rotary must first Fixing the locking lever 58 with respect to the eccentric axis 57 To get picked up. This happens because the jack 64 releases the ratchet lever 59 (Fig. 3). The on that Pawl lever 59 arranged biased tension spring 62 causes then a sudden rotary movement of the ratchet lever 59 and thus also the second axis of rotation 56 or the eccentric axis 57. As a result, the driver 57a releases the nose 58a, which is why the tension spring 69 is also preloaded Locking lever 58 rotates on the eccentric axis 57. Through the two clockwise rotations, i.e. a rotation of the eccentric axis 57 about the axis of rotation 56 and a rotational movement of the locking lever 58 - and thus relative to the - eccentric axis 57, the locking lever experiences one great acceleration towards the base plate 7. The Locking lever comes from the position shown in Fig. 9 in the position shown in Fig. 10, in which the Locking plate 66 presses the tape against the base plate. The Arrangement of the driver 57a of the nose 58a and the Direction of action of the tension spring 69 (FIGS. 9 and 10) on the one Side and the direction of action of the tension spring 62 and the length the backdrop 17 (Fig. 3) on the other hand, are so matched that the latch lever 59, just before the locking plate touches the tape (Fig. 9 and 10) on one Strikes the end of the backdrop 17 to the tab 16. This will the rotation of the axis of rotation 56 stopped and the nose of the Locking lever is no longer on the driver 57a Eccentric axis 57. As a result, the locking lever 58 now rotates only around the eccentric axis 57 and is pressed into the band on. The tension spring 69 also causes the Pressure surface 68 substantially parallel to the slope 67 of the Base plate is aligned and the locking plate already off the first contact with the tape their entire pressure surface presses on the tape.

16, 17, 18 is a highly schematic part a possible closure device according to the invention of the Strapping tool shown. The closure device has a transmission element in the form of a bracket 80, 'in which a counter cam 81 provided with a roller for cam 77 (Fig. 1) is stored. The bracket 80 is also open an axis of rotation 82 on the arm 11 of the base plate of the Strapping device hinged. The bracket 80 is used thus i.a. to transfer a certain part of the Pivotal movement of the lever 9, based on the principle of Friction welding based locking device.

On the same axis of rotation 82 as the bracket 80 is also a supports 83, which extend approximately horizontally, which is via a compression spring 84 on the arm 11 of the base plate supported. An electric motor 85 is on the carrier 83 arranged with which an oscillating movement of a Welding shoe 86 is generated. The carrier 83 is with a Bearing 90 provided at which an angled one-piece lever 91 is articulated. Here is a drive shaft 92 of the motor 85 between the axis of rotation 82 and the bearing 90 for the lever 91, all three Components roughly on an (imaginary) Connecting straight lines 87 can be arranged as shown in Fig. 16 is shown. Via an elastic spring element 93, preferably a plate spring assembly, supports the Carrier 83 against the bracket 80.

One end 91a of the lever is designed as a fork, the both arms form an elongated hole 93 which is open on one side. On the other end 91b of the lever 91 is the welding shoe 86 articulated. One lies in the fork of the lever 91 radial roller bearing arranged on an eccentric element 94.

'The eccentric element is on the shaft 92 of the motor eccentrically supported and with an essentially provided circular peripheral surface on which a Inner ring of the rolling bearing is located. The roller bearing 94a is located with a peripheral surface 94b of its outer ring on both Arms of the fork.

17 is finally a toothed counter plate 96 shown against the one during the welding process Position of the tape is pressed. As in Figs. 16 and 17 can be seen, the counter plate 96 in the arm 11 of the Base plate by an essentially transverse to the longitudinal direction of the tape in the closing device axis 97 pivotally arranged. The axis 97 also runs orthogonal to the pivot axis 86a of the welding shoe 86, the again essentially parallel to the longitudinal direction of the Band 45 is aligned.

With the hand lever 9 and the counter cam 81 acting cams 77 (see also Fig. 1) can Closure device of that shown in FIG. 18 Insertion position in that shown in Fig. 16 Work position. With this movement the carrier 83 via the spring element 93 from the bracket 80 taken. About a not shown Mechanism also switches this movement of the hand lever 9 the motor 85 of the closure device, whereby the Eccentric element 94 begins to rotate. That in the fork eccentrically rotating eccentric element 94 causes one oscillating pivoting movement of the lever 91 along one Circular arc around the bearing. The welding shoe leads this also causes an oscillating movement is indicated by the double arrow 95. So that the Friction welding required pressure force are applied can and the welding shoe is always in contact with the band, presses the spring element 93 on the carrier 83. This can a lifting of the welding shoe 86 due to the itself circular arc-shaped pivoting movement of the lever 91 avoided become. The compression spring 84 serves to reset the carrier 83 and counteracts the spring element 93.

The component thus becomes the drive for the welding shoe 86 the eccentric movement, which is roughly orthogonal runs to the connecting line 87. The for Straight connecting line 87 in approximately parallel component of the Eccentric movement is through the slot of the fork balanced and does not cause the lever 91 to move.

With the swiveling arrangement of the whole Closure device can cause band 45 insertable between the base plate and the welding shoe 86 is. In addition, this can also be used different strip thicknesses resulting in different Distances between the welding shoe 86 and the base plate 7 be balanced. By building this Closure device and in particular through the articulation of the entire locking device on the stationary Axis of rotation 82 is also caused to cause the entire Locking device during a welding phase oscillating movement. Under "welding phase" is to understand the phase in which two layers one Band 45 are welded together. It has shown that with the welding device according to the invention a particularly low-noise friction welding of Plastic straps is possible.

To a with the strapping device according to the invention Belt loop 46 to place a packaged product, close and To disconnect from the tape supply, the device should first be used its base plate 7 can be arranged on the packaged goods. In addition, the hand lever 9 should be in one Starting position, which of those shown in Fig. 2 Intermediate position between the two end positions corresponds. In this position of the hand lever 9 is a locking plate 71st the first backstop 5 and a counter knife 74 of the Cutting device on the base plate. The difference to represent 'of Fig. 2' is in this phase, however no strap has been inserted into the strapping tool yet.

The second and the third backstop 6, 29 are closed solved at this time. In other words, the lock plate 66 of the second backstop 6 is in one position arranged at the greatest distance from the base plate 7 has. In addition, the pawl 44 (Fig. 5) is the third backstop does not engage the ring gear 31 and the tension drive 2 is lifted off the rocker 37. The Welding device is also from its arm 11 Base plate 7 raised.

Then the hand lever 9 is pivoted into an end position, in which it bears against the housing 1 above the swivel drive (Fig. 1). This first movement of the hand lever 9 is over the first swivel arm 13 on the control board 14 transfer. The control board 14 in turn rotates the second Swivel arm 15. Since in this position the claws 54b, 54d of the second pivot arm 15 with the claws 54a, 54c Switch disc 51 are engaged, the rotational movement is on the switching disc 51 and thereby also on the axis of rotation 18 transfer. This movement of the axis of rotation 18 in turn leads to ensure that the clutch (drive cams 49, 50) between the axis of rotation 18 and the first backstop 5 in engagement comes. As a result, the rotational movement of the axis of rotation 18 is increased transfer the backstop 5, whereby the locking plate 71st stands out from the base plate 7. In addition, due to the with the hand lever 9 rotating cam 77 also that Counter knife 74 of the cutter from the base plate 7 lifted off, resulting in a strap guide of the strapping tool for the introduction of a tape end 75 completely is released (Fig.1).

The strap can then be inserted into the strapping tool and be placed around the packaged goods. Here, one should Band loop 46 through an opening 76 in the base plate 7 out and placed in the device so that it is under the backstop 6 both the tape end 75 and 'a another portion of the strap loop 46 is located while under the backstop 5 only the extended one Band end 75 is arranged.

Then the hand lever 9 is again in the Intermediate position according to FIGS. 2 and 3 pivoted. Since the Hand lever 9 is spring-loaded, he only needs to do this be let go, causing him to die Intermediate position. Through this movement of the Hand lever 9, the eccentric axis 48 on the Switch disc 51 in the counterclockwise direction (direction of rotation referred to the representation of FIGS. 1 to 3) rotated, whereby the first backstop 5 on the arm 12 of the base plate 7 lowered and the locking plate 71 between the tape 75 between itself and the base plate 7 is jammed. This movement of the Hand lever also causes the cam 77 to move is also located on the axis of rotation 10 of the hand lever 9, a control plate 78 of the clipping and Locking device 3, 4 actuated. 16 to 18 operates the closure device for this purpose Cam 77 the counter cam 81. This lowers it Counter knife 74 on the tape, while the state of Closure device remains unchanged. In addition, should at the latest now the band 45 also in the gap between the Tensioning wheel 30 and the counter rollers 39, 40 of the rocker 37 are introduced (see. Fig. 5, 6, 7).

In order to tension the tape, a (not shown) Tension button of the hand lever 9 actuated, whereby the DC motor of the tension drive 2 is started. The drive movement of the motor is controlled by the Transfer the planetary gear to the tensioning wheel 30, which - by rotating it counterclockwise - the tape in the direction (arrow 43 in FIGS. 2 and 5) to one not withdrawing the illustrated supply roll. The movement of the Tensioning wheel is stopped when the intended tension on the tape is applied, for which the current actual Motor current is compared with a nominal value of the current. When the setpoint is reached, the engine is switched off, where the setpoint of the motor current of a certain desired nominal belt tension of a certain belt type equivalent.

During this tensioning phase, the backstop 5 clamps the Band end. In addition, the pawl 28 is in the position shown in Fig. 6, in which it has a rotational movement the rotating against the direction of rotation of the tensioning wheel 30 Ring gear 31 only in one direction of rotation. Since that Ring gear 31 is rotationally coupled to the tensioning wheel thus the tensioning wheel against rotation against Clamping direction blocked. The tension wheel can thus at most by 180 ° in the opposite direction to the clamping direction Turn direction. Then at the latest the latch will snap into one of the two recesses 35, 36 of the ring gear 31.

After this tensioning phase has ended, the hand lever 9 - starting from the intermediate position (see FIGS. 2 and 3) - transferred to its second end position, shown in Fig. 11 is. The movement of the control board 14 triggered thereby leads to the nose 65 of the control board 14 the pawl 64 rotates out of its locked position, causing the latch lever. 59 becomes free for counterclockwise rotation. in the Course of the movement of the hand lever 9 towards it second end position, the tab 16 can now the pawl lever 59th Turn counterclockwise (Fig. 12). Unlike the movement of the hand lever 9 from the intermediate position in the ratchet lever is now in the first end position and back one of the ends of the backdrop 17 and is through the tab 16 coupled to the movement of the control board 14.

Since the pawl lever 59 with the axis of rotation 56 rotatably is connected, the movement of the ratchet lever 59 leads to a lowering of the locking plate 66 in the direction of the Base plate 7, which also makes the backstop 6 the belt stuck. Due to the previously described articulation of the Locking plate 66 ensures that the locking plate: the first time you touch the tape in the substantially parallel to the slope 67 of the base plate 7 is aligned and the tape is clamped very quickly can be.

In the further course of the movement of the hand lever 9 in The control board comes towards its second end position 14 in a position in which the second pivot arm 15 so is positioned that the coupling between the swivel arm 15 and the double lever 19 engages. Until the hand lever 9 its has reached the second end position, the second swivel arm 15 rotates the double lever 19 in the counterclockwise direction from that in Fig. 6 shown position in the end position shown in Fig. 7. As can be seen in Fig. 6, during the tensioning phase the double lever 19 with the lever arm 24 of the second Double lever 25 no contact. Only in the course of the others Movement of the hand lever 9 presses one of the two arms 20, 21 against the lever arm 24. This gives the pawl 28 that Ring gear 31 free. The third acting on the tensioning wheel 30 The backstop is now canceled. This causes that of the band section between the tensioning wheel 30 and the second Backstop 6 the previously applied tape tension in essentially taken again. The band tension on the essentially between the two backstops 5, 6 belt loop remains unchanged.

By a further pivoting movement of the hand lever 9 in Direction to a second end position is subsequently the Counter knife 74 activated, the tape loop 46 from the tape separates. The welding device then connects the two ends of the band by friction welding. Both processes are initiated by the hand lever 9, the movement of which Cam 77 is transferred to the control plate 78, the again the counter knife and the welding device responds. Both the cutting and the welding process are relieved of this immediately . affected band section considerably facilitated.

Claims (23)

1. A wrapping device for wrapping packaged material with a strap, wherein said wrapping device has a tensioning device operatively connected to a tensioning drive for tensioning the strap, a locking device for locking two strap ends of a strap and a plurality of back stops for fixing the strap on the wrapping device, wherein said tensioning device is provided with a rocker (37) arranged towards a tensioning wheel (30), said rocker (37) is pivotally mounted about a rocker axis (38), said tensioning wheel (30) and said rocker (37) are moveable onto one another, whereby said strap can be clamped between said rocker and said tensioning wheel and said strap rests on said tensioning wheel with a looping angle (α),
   characterised in that
   said rocker (37) is provided with two counterrollers (39, 40), each rotatably mounted about their axis, wherein the axes are aligned at least substantially parallel to the rocker axis (38) of the rocker and with respect to a tensioning direction one axis is located before and one axis is located after the rocker axis.
2. The wrapping device according to claim 1, characterised in that said rocker (37) is provided with a bearing surface on which the strap can be pressed by the tensioning wheel.
3. The wrapping device according to claim 2, characterised in that said bearing surface has a curvature wherein at least one section of the curvature of said bearing surface is provided with a radius which substantially corresponds to the radius of the tensioning wheel.
4. The wrapping device according to one or a plurality of the preceding claims, characterised in that said tensioning wheel (30) and said rocker (37) are arranged behind the locking device (3) with reference to the tensioning direction.
5. The wrapping device according to one or a plurality of the preceding claims, characterised in that one of the back stops is arranged in front of the locking device with reference to the tensioning direction.
6. The wrapping device according to one or a plurality of the preceding claims, characterised in that one of the back stops (5, 6, 26) is provided to block said tensioning wheel (30), whereby said tensioning wheel can be blocked against rotational movement in the opposite direction to the tensioning direction.
7. The wrapping device according to one or a plurality of the preceding claims, characterised in that said rocker is supported on a base plate (7) on which components of the wrapping device are supported.
8. The wrapping device according to claim 7, characterised in that a first part of the base plate is assigned to the locking device and a second part of the base plate is assigned to the tensioning device, said rocker is supported on the second part of said base plate and between the two parts of the base plate a slot is formed for passing through a strap section.
9. The wrapping device according to one or a plurality of the preceding claims, characterised in that the welding device is provided with a lever (91) having an eccentric mass (94) operatively connected to a motor shaft acting on its one end to transmit an eccentric movement relative to the motor shaft of the locking device to said lever and having a welding shoe (86) arranged at its other end, wherein said lever is pivotally mounted on a pivotal axis so that the movement of the eccentric' mass results in an oscillating forward and backward movement of the welding shoe.
10. The wrapping device according to claim 9, characterised in that the pivotal axis of said lever (91) is mounted on a support (83) on which a drive of the locking device is arranged, said support sits on a positionally fixed pivot (82) with reference to a base plate of the device to perform pivotal movements, wherein on said pivot (82) there is also located a transmission element to transmit a pivotal movement of a hand lever of the device and said transmission element and said lever are operatively connected one to the other.
11. The wrapping device according to claim 10, characterised in that the operative connection between said transmission element constructed as a clamp (80) and said lever comprises an elastic element arranged between said transmission element and said support.
12. The wrapping device according to one or a plurality of the preceding claims 9 to 11, characterised in that said support with an elastic element rests on a component which is positionally fixed with respect to the base plate or the base plate itself.
13. The wrapping device according to one or a plurality of the preceding claims 9 to 12, characterised in that the lever has a kink in its longitudinal extension.
14. The wrapping device according to claim 9, characterised in that the tensioning drive is arranged behind the locking device in the tensioning direction.
15. The wrapping device according to one or a plurality of the preceding claims 9 to 14, characterised by at least two back stops (5, 6, 26) of which at least one back stop is arranged in front of the locking device (3) and one back stop is arranged after the locking device with reference to a tensioning direction of the strap.
16. The wrapping device according to one or a plurality of the preceding claims, characterised in that as a means for controlling functions of said wrapping device there is provided a substantially plate-shaped control plate (14) which is operatively connected to an actuating means, a movement of the actuating means brings about a pivotal movement of said control plate, and the pivotal movement of said control plate (14) can be transmitted to a plurality of transmission means pivoted on the control plate, with which said back stops (5, 6, 26) can be transferred from a locking position to a release position and vice versa.
17. The wrapping device according to claim 16, characterised by at least one back stop, a transmission means is constructed as a pivot (18, 56), with which the at least one back stop (5, 6, 26) can be actuated, wherein at least one clutch is provided which actuates the back stop in specific rotation positions of the shaft and releases it in other positions.
18. The wrapping device according to one or both of the preceding claims 16 or 17, characterised in that pivoted on the control plate is a further pivot with which a second back stop can be actuated.
19. The wrapping device according to one or both of the preceding claims 16 or 17, characterised in that at least one of the back stops is supported with a locking lever (58) on an eccentric axis (48, 57), said eccentric axis (48, 57) executes an eccentric movement towards the at least one pivot and rotational relative movements can be executed with the locking lever in specific rotation positions of the pivot towards the eccentric axis.
20. The wrapping device according to one or a plurality of the preceding claims, characterised in that a first part of the base plate is assigned to the locking device and a second part of the base plate is assigned to the tensioning device and between the two parts of the base plate there is formed a channel through which a strap loop can be guided.
21. The wrapping device according to one or a plurality of the preceding claims, characterised in that a locking lever of the at least one back stop is supported on an eccentric axis which is connected to a pivot and which is arranged eccentrically with respect to said pivot.
22. The wrapping device according to claim 21 characterised in that said locking lever is rotationally connectable to said pivot via a clutch and is arranged freely rotatably on said eccentric axis.
23. The wrapping device according to one or a plurality of the preceding claims, characterised by a gearing of the tensioning device which has at least three reduction stages.

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