Bundling Tool for Waste-Free Bundling of Binding Material

Abstract

The disclosure relates to a bundling tool for waste-free bundling of a bundling good via an endless strap. The tool includes a jaw unit, a lock feeding unit, a pushing and pulling unit, a sensor unit, and a cutting unit. The tool further includes a control unit, which is arranged in a normal operating mode, for a first path portion of the path for the pushing and pulling unit during pushing, to preset a greater advance speed of the end section than for a second path portion following the first path portion wherein the second path portion comprises the part of the path extending back into the lock element in order to provide an improved bundling tool for waste-free bundling of a bundling good, in particular a more reliable, faster and easier-to-operate bundling tool.

Claims

1. A bundling tool for bundling a bundling good through use of a strap, the bundling tool comprising: a jaw unit configured for guiding an end section of the strap around the bundling good; a lock feeding unit configured for providing a lock element for the strap; a pushing and pulling unit configured for pushing, utilizing a motor, the end section of the strap along a path through the lock element, along the jaw unit with the bundling good gripped by the jaw unit, around the bundling good, and back into the provided lock element, the pushing and pulling unit further configured for the subsequent retraction of the end section of the strap; a sensor unit configured for detecting the end section pushed back into the lock element; a cutting unit configured for separating the end section arranged around the bundling good from a remaining section of the strap, the remaining section remaining in the bundling tool; and a control unit configured to preset, for the pushing and pulling unit during pushing in a normal operating mode, a greater pushing speed of the end section for a first path portion of the path than for a second path portion following the first path portion, the second path portion comprising a part of the path running back into the lock element.

2. The bundling tool according to claim 1, wherein the control unit is designed to: in a calibration operating mode for the first path portion for the pushing and pulling unit, preset a lower pushing speed of the end section than in the normal operating mode; and in the calibration operating mode, determine an equivalent-of-distance for at least the first path portion.

3. The bundling tool according to claim 2, wherein the control unit is further designed to preset as the pushing speed in the first path portion, in the calibration operating mode for the first path portion for the pushing and pulling unit, the pushing speed of the second path portion in the normal operating mode.

4. The bundling tool according to claim 2, wherein the control unit is adapted to determine, in the calibration operation mode, the equivalent-of-distance with a counting of motor steps in the motor of the pushing and pulling unit during pushing of the end section.

5. The bundling tool according to claim 4, wherein the control unit is designed to deactivate the calibration operating mode automatically after the equivalent-of-distance has been determined at least once.

6. The bundling tool according to claim 4, wherein the control unit is designed to activate the calibration operating mode automatically after the bundling tool is switched on.

7. The bundling tool according to claim 2, wherein the control unit is designed to deactivate the calibration operating mode automatically after the equivalent-of-distance has been determined at least once.

8. The bundling tool according to claim 7, wherein the control unit is designed to deactivate the calibration operating mode after the equivalent-of-distance has been determined twice.

9. The bundling tool according to claim 8, wherein the control unit is designed to activate the calibration operating mode automatically after the bundling tool is switched on.

10. The bundling tool according to claim 2, wherein the control unit is designed to activate the calibration operating mode automatically after the bundling tool is switched on.

11. The bundling tool according to claim 1, wherein the control unit, in the normal operating mode, is configured to: detect an equivalent-of-time at which the end section pushed back into the lock element is detected by the sensor unit; check whether the detected equivalent-of-time coincides with an equivalent-of-time stored for pushing by the pushing and pulling unit; and continue in the normal operating mode only if the two equivalent-of-times coincide.

12. The bundling tool according to claim 11, wherein the control unit is adapted to determine the equivalent-of-time by counting motor steps in the motor of the pushing and pulling unit during pushing of the end section.

13. The bundling tool according to claim 12, wherein the control unit is designed to, in the event of a deviation of the two equivalent-of-times from one another, at least one of: activate the calibration operating mode; or check whether the detected equivalent-of-time is greater or smaller than the stored equivalent-of-time, and, in the case of a greater detected equivalent-of-time, to increase the first path portion with the greater pushing speed of the end section, and, in the case of a smaller detected equivalent-of-time, to decrease the first path portion with the greater pushing speed of the end section.

14. The bundling tool according to claim 11, wherein the control unit is designed to, in the event of a deviation of the two equivalent-of-times from one another, at least one of: activate the calibration operating mode; or check whether the detected equivalent-of-time is greater or smaller than the stored equivalent-of-time, and, in the case of a greater detected equivalent-of-time, to increase the first path portion with the greater pushing speed of the end section, and, in the case of a smaller detected equivalent-of-time, to decrease the first path portion with the greater pushing speed of the end section.

15. The bundling tool according to claim 1, wherein the jaw unit is an exchangeable jaw unit that comprises a fully mechanical jaw unit.

16. The bundling tool according to claim 1, wherein the jaw unit is an exchangeable jaw unit that further comprises at least two different jaw units of different sizes.

17. A method for automatically calibrating a bundling tool configured to bundle a bundling good via a strap, the method comprising: pushing, utilizing a feed motor, an end section of the strap along a path through a lock element and along a jaw unit of the bundling tool back into the lock element; detecting a reaching of an end position of the end section pushed into the lock element; determining a number of motor steps of the feed motor required for pushing the end section into the end position; setting a first pushing speed for the motor steps corresponding to a first path portion of the path for a future pushing; and setting a second pushing speed, lower than the first pushing speed, for the motor steps of the future pushing corresponding to a second path portion of the path following the first path portion.

18. The method according to claim 17, wherein during pushing the end section is pushed around the bundling good.

19. A method for bundling a bundling good via of a strap, the method comprising: pushing an end section of the strap along a path through a lock element and along a jaw unit of a bundling tool back into the lock element, wherein a pushing speed of the end section in a first path portion of the path is greater than in a second path portion of the path following the first path portion.

20. The method of claim 19, further comprising: separating the end section from a remaining section of the strap remaining in the bundling tool.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Example embodiments are described in more detail below with reference to schematic drawings, which therein show:

[0033] FIG. 1 is a schematic representation of an example bundling tool;

[0034] FIG. 2 is a schematic sectional view of an example embodiment of a bundling tool;

[0035] FIG. 3 is a detail of FIG. 2; and

[0036] FIG. 4 is a schematic illustration of an example bundling tool with examples of jaw units of different sizes.

[0037] In the figures, identical or functionally-similar features are provided with the same reference signs.

DETAILED DESCRIPTION

[0038] The disclosure relates to a bundling tool for waste-free bundling of a binding material/bundling good by means of an endless strap or strap, include an exchangeable jaw unit for guiding an end section of the endless strap around the bundling good, a lock feeding unit for providing a lock element for the endless strap, and a pushing and pulling unit for pushing the end section of the endless strap by means of a motor along a path through the provided lock element as well as along the jaw unit, when the bundling good is gripped by the jaw unit (e.g., when the endless strap is used as intended) with the end section of the endless strap around the bundling good, and back into the provided lock element, and for subsequent retraction of the end section of the endless strap and thus tightening of the endless strap around the bundling good, with a sensor unit for detecting the end section pushed back into the lock element, and with a cutting unit for separating the end section arranged around the bundling good from a remaining section of the endless strap remaining in the bundling tool.

[0039] FIG. 1 schematically shows an example bundling tool. In the present case, the bundling tool 1 has a central housing 1a with a handle unit 1b. Instead of the handle unit 1b, the central housing 1a may have a mechanical and/or electrical interface for coupling with a robot. The bundling tool 1 has an exchangeable jaw unit 2 for guiding an end section 3a of an endless strap 3 around a bundling good 4. The endless strap 3 has a toothing 3b, which in the present case is arranged on an outer side of the endless strap 3 facing away from the bundling good 4 during intended use. In the example shown, the endless strap 3 is fed from a reservoir unit 1c, in which it is held, for example, in the form of a roll. The reservoir unit 1c can be designed as a separate unit from the bundling tool 1.

[0040] The jaw unit 2 has an upper jaw claw 2a and a lower jaw claw 2b which can be opened and closed. A lock feeding unit 5 provides a respective lock element 15 for the current bundling process from an external or internal reservoir of lock elements 15 not shown here.

[0041] The bundling tool 1 also has a pushing and pulling unit 6, which is provided, in the present example, with a drive 6a engaging in the toothing 3b for pushing the end section 3a of the endless strap 3 by means of a motor along a path 7 through the provided lock element 15 as well as along the jaw unit 2, with the bundling good 4 gripped by the jaw unit 2 around the bundling good 4, and back into the provided lock element 15, as well as for the subsequent retraction of the end section 3a of the endless strap 3.

[0042] The bundling tool 1 also has a sensor unit 8 for detecting the end section 3a pushed back into the lock element 15, in this case with a mechanical stop element 8a, against which one end 3a of the end section 3a abuts during the pushing along the path 7 and thus triggers a sensor signal. A cutting unit 9 for separating the end section 3a arranged around the bundling good 4 from a remaining section 3c of the endless strap 3 remaining in the bundling tool 1 after the end section 3a has been pulled back and thus after the bundling good 4 has been tied is also part of the bundling tool 1. The separation takes place in this case by means of a blade element 9a, which is moved here in the positive y-direction in order to cut off and thus separate the remaining section 3c protruding in the positive x-direction over the lock element 15 (e.g., which at least in parts then forms the new end section to be guided around the bundling good 4 in a subsequent bundling process) after the retraction.

[0043] Finally, the bundling tool 1 has a control unit 10 which is designed to preset, in a normal operating mode for a first path portion 7a (FIG. 2) of the path 7 for the pushing and pulling unit 6 during pushing, a greater pushing speed of the end section 3a than for a second path portion 7b (FIG. 2) following the first path portion 7a, the second path portion 7b comprising the part of the path 7 running back into the lock element 15.

[0044] In FIG. 2, the path 7 is shown in more detail. In the example shown there, the second path portion 7b runs from a point 7y of the path 7 to an end point 7z of the path 7, to which the end section 3a is pushed back through the lock element 15. In the present example, the first path portion 7a runs from a starting point 7x of the path 7 at the mouth of the lock element 15, through which the end section 3a is pushed at the beginning of the respective bundling process.

[0045] The respective path portions 7a, 7b, more precisely their lengths, which can be measured and/or specified in an equivalent-of-distance such as a number of teeth of the toothing 3b and/or a number of encoder or motor steps of the drive 6a or the associated motor, can be determined in a calibration operating mode of the control unit 10 for the respective jaw unit 2 used. In this way, the behavior of the pushing and pulling unit 6 in use can be determined partially or fully automatically for the respective size of the jaw unit 2, e.g., the length of the path 7 caused by the design.

[0046] Preferably, the control unit 10 is then designed to specify a lower pushing speed of the end section 3a for the pushing and pulling unit 6 in the calibration operating mode for the first path portion 7a than in the normal operating mode and to determine the equivalent-of-distance, for example one of the above-mentioned equivalent-of-distances, for the first path portion 7a in the calibration operating mode. This can be done, for example, by determining the equivalent-of-distance for the entire path 7, for example, by counting a total number of encoder steps or number of teeth of the toothing 3b starting from a start of pushing the end section 3a to a triggering of the sensor signal when the end point 7z is reached, and then subtracting a stored number of encoder steps or teeth corresponding to the second path portion 7b from the total number.

[0047] In the calibration operating mode, the pushing speed for the second path portion 7b can be preset in the normal operating mode for the first path portion 7a and also for the second path portion 7b for the pushing and pulling unit 6. However, it is also possible for the first path portion 7a and/or for the second path portion 7b to have a different pushing speed, for example a pushing speed that is even lower than that of the second path portion in the normal operating mode. In principle, the equivalent-of-distance can be determined with better accuracy at a lower pushing speed than at a higher pushing speed. In practice, it is necessary to weigh up between a desired higher speed of the bundling process and a desired higher accuracy when determining the equivalent-of-distance.

[0048] The length of the second path portion 7b is to be preset by and/or for the control unit 10 to be as short as possible, whereby respective switching speeds between pushing the endless strap 3 in a forward direction F (FIG. 3) and the subsequent retraction of the endless strap 3 in a reverse direction R (FIG. 3) of the control unit 10 and/or the pushing and pulling unit 6 are a limiting factor.

[0049] The first path portion 7a does not have to start at the starting point 7x either, it can also start at a further point 7x. In calibration mode, too, a higher pushing speed can be specified for an initial path portion between points 7x and 7x, for example the higher pushing speed of the normal operating mode. The length of the initial path portion can be, for example, the length of the first path portion 7a from starting point 7x to point 7y for a smallest jaw unit 2 used or available for the bundling tool 1 and/or a shorter length.

[0050] Alternatively or in addition to the described calibrating operation mode, the normal operation mode may also comprise or be a calibrating normal operation mode. This is explained by way of example with reference to FIG. 3.

[0051] At the beginning of the bundling process, the end 3a of the endless strap 3 is at the start position 7x. After a bundling process trigger signal, the end 3a and the end section 3a adjoining the end 3a are first pushed by the pushing and pulling unit 6 in the forward direction F through the lock element 15 and along the path 7. As soon as the corresponding equivalent-of-distance is reached, for example a predetermined number of encoder or motor steps, the pushing speed is reduced when position 7y is reached in order to reduce the probability of faulty tying. When the end position 7z is reached, the sensor signal is triggered and the push/pull unit now pulls the endless strap 3 back in the reverse direction R to bundle the material to be bound 4 as intended.

[0052] In the calibrating normal operating mode, an equivalent-of-time (e.g., a relative equivalent-of-time) between the bundle process trigger signal and the sensor signal can be detected and compared with a stored equivalent-of-time (e.g., a stored relative equivalent-of-time). In aspects, only if the two equivalents-of-time match is it possible to continue with the previous normal operating mode, e.g., the previous lengths for the first and/or second equivalent-of-distance 7a, 7b.

[0053] If the sensor signal is triggered later than expected according to the stored equivalent-of-time, this indicates a jaw unit 2 is used whose size is increased compared to the jaw unit for which the relative equivalent-of-time is stored. If the sensor signal is triggered earlier than expected according to the stored equivalent-of-time, this indicates a jaw unit 2 is used whose size is reduced compared to the jaw unit for which the relative equivalent-of-time is stored. Accordingly, the control unit 10 can automatically adjust the length of the first path portion 7a to the later or earlier triggering of the sensor signal (e.g., lengthen or shorten it accordingly), and then in turn adjust the stored equivalent-of-time to the new length of the first path portion 7a. In this way, the bundling tool 1 calibrates itself during the intended use and adjusts itself accordingly in an optimal way to jaw units 2 of different sizes.

[0054] FIG. 4 shows example jaw units 2, 2, 2, 2 of different sizes on an example bundling tool 1. The jaw units 2, 2, 2, 2 can be repeatedly exchanged without destruction, preferably without tools or with a limited number and/or complexity of tools. Corresponding to the different sizes of the jaw units 2, 2, 2, 2, the respective paths 7, 7 and thus in particular also the first path portions 7a are each of different length. The second path portions 7b, on the other hand, can be of the same length, since the suitable length is determined by further properties of the respective bundling tool 1, such as, for example, a reaction speed of the control unit 10.

[0055] Unless context dictates otherwise, use herein of the word or may be considered use of an inclusive or, or a term that permits inclusion or application of one or more items that are linked by the word or (e.g., a phrase A or B may be interpreted as permitting just A, as permitting just B, or as permitting both A and B). Also, as used herein, a phrase referring to at least one of a list of items refers to any combination of those items, including single members. For instance, at least one of a, b, or c can cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c, or any other ordering of a, b, and c). Further, items represented in the accompanying figures and terms discussed herein may be indicative of one or more items or terms, and thus reference may be made interchangeably to single or plural forms of the items and terms in this written description. Still further, the use of preferably, generally, typically, and grammatically-related terms in this disclosure are not utilized to limit the scope of the claims or to imply that certain features are critical, essential, or even important to the disclosed structures or functions. Rather, these terms are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the disclosed subject matter.