Cable Tie Tightening Device with Cutting Functionality

Abstract

Disclosed are cable tie tightening devices with cutting functionality, including a gripping unit configured to grip and pull a cable tie strap until an adjustable force limit is reached, a cutting unit configured to cut the strap, an actuator unit configured to automatically actuate gripping and cutting units, a force adjusting unit configured to adjust the adjustable force limit, where the gripping unit is attached to a piston element of the actuator unit at one side and the force adjusting unit includes a retaining element configured to retain a cylinder element of the actuator unit in a given position until the adjustable force limit is reached, while the retaining element is configured to be connected directly with the cylinder element when retaining the cylinder element in the given position, and to be disconnected from the cylinder element when the adjustable force limit is reached or exceeded.

Claims

1. A cable tie tightening device with cutting functionality, comprising: a gripping unit configured to grip a cable tie strap and pull the cable tie strap until an adjustable force limit is reached; a cutting unit configured to cut the cable tie strap; an actuator unit configured to automatically actuate the gripping unit and the cutting unit, the gripping unit attached to a piston element of the actuator unit at one side of the actuator unit; and a force adjusting unit configured to adjust the adjustable force limit, the force adjusting unit comprising a retaining element configured to retain a cylinder element of the actuator unit in a given position until the adjustable force limit is reached, the retaining element configured to be connected directly with the cylinder element when retaining the cylinder element in the given position, and to be disconnected from the cylinder element when the adjustable force limit is reached or exceeded.

2. The cable tie tightening device according to claim 1, wherein at least one of the retaining element or the force adjusting unit is arranged at a second side of the actuator unit opposite to a first side.

3. The cable tie tightening device according to claim 1, wherein at least one of the retaining element or the force adjusting unit is arranged coaxially with the piston element.

4. The cable tie tightening device according to claim 1, wherein the force adjusting unit comprises a spiral spring element, the extension of which in an axial direction, and thereby a spring force of which, is configured to be adjusted to adjust the adjustable force limit, which is arranged such that a central axis of the spiral spring element runs along a central axis of the piston element.

5. The cable tie tightening device according to claim 4, wherein the central axis of the spiral spring element is aligned with the central axis of the piston element.

6. The cable tie tightening device according to claim 1, wherein the retaining element is a hook element configured to engage with an integral part of the cylinder element and configured to disengage from the integral part of the cylinder element when the retaining element is disconnected from the cylinder element.

7. The cable tie tightening device according to claim 6, wherein the hook element is configured to engage with an eyelet or a pin of the cylinder element when the retaining element is connected with the cylinder element to retain the cylinder element in the given position.

8. The cable tie tightening device according to claim 4, wherein the cylinder element has a driving element configured to actuate the cutting unit through a movement of the driving element along the cutting unit in a direction running along the axial direction.

9. The cable tie tightening device according to claim 8, wherein the cutting unit comprises a lever element, one end of which is connected to a blade element configured to cut the cable tie strap, and an opposite end of which features a guiding surface which is configured to translate a movement of the driving element in the axial direction into a movement of the lever element in a radial direction running transverse to the axial direction.

10. The cable tie tightening device according to claim 1, wherein the force adjusting unit comprises a lever element, one end of which is comprising the retaining element, and an opposite end of which is connected to a further element of the force adjusting unit.

11. The cable tie tightening device according to claim 10, wherein the force adjusting unit comprises a spiral spring element and the opposite end of the lever element is connected to the spiral spring element.

12. The cable tie tightening device according to claim 1, wherein the force adjusting unit comprises a lever element, one end of which is connected to the retaining element, and an opposite end of which is connected to a further element of the force adjusting unit.

13. The cable tie tightening device according to claim 12, wherein the force adjusting unit comprises a spiral spring element and the opposite end of the lever element is connected to the spiral spring element.

14. The cable tie tightening device according to claim 1, wherein the gripping unit, cutting unit, actuator unit, and force adjusting unit are at least partially arranged in a housing unit forming a handle part, wherein said gripping unit, cutting unit, actuator unit, and force adjusting unit are arranged at the same side of the handle part.

15. The cable tie tightening device according to claim 14, wherein said gripping unit, cutting unit, actuator unit, and force adjusting unit are arranged at the same side of a trigger element configured to trigger the actuator unit.

16. A method for tightening and cutting a cable tie, comprising: gripping a cable tie strap with a gripping unit; pulling the gripped cable tie strap until an adjustable force limit is reached, by moving a piston element of an actuator unit which is attached to the gripping unit relative to a cylinder element of the actuator unit; disengaging a retaining element of a force adjusting unit from an integral part of the cylinder element, thereby allowing an axial movement of the cylinder element relative to a housing unit; and actuating a lever element of a cutting unit, one end of which is connected to a blade element, by an interaction of the axially moving cylinder element with an opposite end of the lever element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Exemplary embodiments are described in more detail below with reference to schematic drawings. Therein

[0024] FIG. 1 shows an exemplary embodiment of a cable tie tightening device with cutting functionality in a first state; and

[0025] FIG. 2 shows the exemplary embodiment of FIG. 1 in a second state.

[0026] In the figures, the same or functionally identical features are provided with the same reference signs.

DETAILED DESCRIPTION

[0027] The figures show an exemplary embodiment of a cable tie tightening device 1 in a side view with one part of the housing unit 2 and some further parts like pneumatic hoses removed for better clarity. FIG. 1 shows the cable tie tightening device 1 in a first state which corresponds to an initial configuration where the cable tie tightening device 1 is about to be used. FIG. 2 shows the cable tie tightening device 1 in a second state which corresponds to an final configuration where the cable tie tightening device 1 has been used and just cut the cable tie strap. After the second state, the cable tie tightening device 1 can automatically reconfigure into the first state.

[0028] The cable tie tightening device 1 with cutting functionality comprises a gripping unit 3, a cutting unit 4, an actuator unit 5, and a force adjusting unit 6 that are at least partially arranged in the housing unit 2 (the actuator unit 5 being arranged completely in the housing unit 2 here). The housing unit 2 comprises a handle part 2a and a trigger element 2b in the present example. The trigger element 2b is configured to trigger the actuator unit 5.

[0029] The gripping unit 3 is configured to grip a cable tie strap (not shown) and to pull the cable tie strap until an adjustable force limit is reached (towards the actuator unit 5, in positive x-direction here). The cutting unit 4 is configured to cut the cable tie strap when the force limit is reached/exceeded. The actuator unit 5 is configured to automatically actuate gripping unit 3 and cutting unit 4, here to pneumatically actuate the other units 3, 4. The force adjusting unit 6 configured to adjust the adjustable force limit. This can be implemented by means of an adjustment wheel 6a, for instance. In the present example, said units 3, 4, 5, 6 are arranged at the same side of the handle part 2a, i.e. the upper side which is the side above the trigger element 2b here (in positive y-direction). Since this arrangement makes space in the handle part 2a, a pneumatic valve element 2c may be placed there. This allows a slimmer design of the upper side of the housing unit 2 and thereby the cable tie tightening device 1.

[0030] The gripping unit 3 is attached to a piston element 5a of the actuator unit 5 at one side (the front side, oriented in the negative x-direction here) of the actuator unit 5. The force adjusting unit 6 comprises a retaining element 6b configured to retain a cylinder element 5b of the actuator unit 5 in a given position until the adjustable force limit is reached. This given position is the position of the cylinder element 5b in the first state shown in FIG. 1. As the retaining element 6b is configured to be connected directly with the cylinder element 5b when retaining the cylinder element 5b in the given position, it engages an integral part of the cylinder element 5b, here a pin 5b. An integral part of a unit can be understood as a part that is fixed relative to the other parts of the unit, i.e. cannot be moved relative to the other parts of the unit. The retaining element 6b is also configured to be disconnected from the cylinder element 5b when the adjustable force limit is reached or exceeded (see FIG. 2). To this end, it is formed as a hook element here. Consequently, the cylinder element 5b itself is movable in the axial direction (when not held in place by retaining element 6b). A longitudinal axis of the cylinder element 5b, which may align with its main extension direction, is running along the axial direction in this example (x-direction here). This is implemented, in the current example, by one or more holders 2d of the housing unit 2 that hold the cylinder element 5b in place but allow gliding of the cylinder element 5b back and forth (x-direction here) relative to the holders 2d, i.e. housing unit 2.

[0031] In the present example, the retaining element 6b and the force adjusting unit 6 are arranged at a second side (the back side, oriented in positive x-direction here) of the actuator unit 5 opposite to the first side. This is done in such a way here that the retaining element 6b and the force adjusting unit 6 are arranged coaxially with the piston element 5a. In particular, the force adjusting unit 6 comprises a spiral spring element 6c, the extension of which in an axial direction (x-direction here), and thereby a spring force of which, is configured to be adjusted to adjust the adjustable force limit. This spiral spring element 6c is arranged such that a central axis A (along the axial direction) of the spring element 6 is aligned with the central axis B of the piston element 5a here (which is also the central axis of the cylinder element 5b). Advantageously, the pin 5b, i.e. the integral part of the cylinder element 5b the retaining element 6b interacts (engages/disengages) with is also aligned with the central axes A, B.

[0032] Here, the cylinder element 5b has a driving element 5b, here formed as another integral part. The driving element 5b is configured to actuate the cutting unit 4 by means of a movement of the driving element 5b along the cutting unit 4, here along a guiding surface 4a of a lever element 4a, in a direction running along the axial direction (negative x-direction here). The guiding surface 4a is configured to translate a movement of the driving element 5b in the axial direction into a movement of the lever element 4a in a radial direction (here y-direction). In the present case, due to pivot 4c, a (front) end of the lever element 4a with blade element 4b moves up (here positive y-direction) when the (back) end of the lever element 4a with the guiding surface 4a is driven down (here negative y-direction) when the cylinder element 5b with the driving element 5b is moving forward (in the negative x-direction).

[0033] During intended use, the shown exemplary cable tie tightening device 1 can be used to grip a cable tie strap with the gripping unit 3 and pull it backwards (in the positive x-direction). As long as a pulling force exerted onto the cable tie strap in this process (by the gripping unit 3), the piston element 5a will move (backwards, in the positive x-direction) relative to the associated cylinder element 5b. The cylinder element 5b will stay in the position shown in FIG. 1 in spite of being itself movable in the axial direction (here x-direction), since retaining element 6b is engaged with the cylinder element 5b, i.e. with pin 5b. Thus, the pulling force acts on the retaining element 6b, i.e. the force adjusting unit 6.

[0034] When the pulling force reaches/exceeds the set/adjusted force limit, the retaining element 6b disengages the cylinder element 5b, here pin 5b, and allows the cylinder element 5b to move frontwards (negative x-direction here), with the driving element 5b actuating the cutting unit 4. The position finally reached is shown in FIG. 2. Here, blade element 4b is moved upwards and has cut the cable tie strap. As compared to FIG. 1, the cylinder element 5b is positioned closer to the front of the cable tie tightening device 1 (end part of cable tie tightening device 1 in negative x-direction). The retaining element 6b is disengaged from the cylinder element 5b by being rotated around pivot 6d. This rotation is prevented by the spiral spring element 6c for pulling forces below/up to the adjusted force limit.