EP0142001B1 - Device for tying a bundle of electrical leads - Google Patents

Abstract

In a device for automatically looping a thread about a bundle of wires to form a continuous crocheted tying structure, a camming mechanism is provided for limiting the tying cycles to two and for adding a plurality of knotting cycles. A cutting knife and an intercept needle are reciprocatably mounted to the housing of the device and are shifted by a pneumatic cylinder under control of the camming mechanism. The knife cuts the thread after the formation of a plurality of knot loops, while the intercept needle catches the thread and holds it for the next work operation.

Description

The invention relates to a device for binding a bundle of electrical lines according to the preamble of claim 1.

In many areas of technology, there is a requirement to bind several electrical lines together. For example, in the case of electrical equipment, cable harnesses with cables routed in parallel over long distances or motor winding heads must be fixed with cable bundles. It is known to hold bundles of lines together with separate plastic cable ties, each of which has an individual closure. This requires special cable ties, which are prefabricated as plastic parts and are comparatively expensive. Methods and devices with which cable harnesses or the like can be bound have also already been proposed. The cable harness is continuously wrapped mechanically by a device called a winding device in the manner of a crochet process with twine laid in loops; at the end of the binding process, the end of the thread is manually separated and knotted.

The latter method is described in detail in DE-A-25 33 640. With a device designed in this way, it is in particular possible to machine a wire harness continuously and continuously, the stability of the thread bundle created should be achieved by means of a double thread in each case during the loop formation. Knotting and cutting off the twine is not possible with this device, so that fully automatic operation is not yet achieved. The latter peculiarity of the device previously known from DE-A-25 33 640 is regarded by the experts as disadvantageous since practical work cannot be carried out.

In addition, from DE-A-2705418 an automatic binder for binding an object with a long, flexible binding material is known, each having a guide device, a conveyor, a tightening device and a gripping device for the flexible material. The purpose of this is to place loops of the material, which consists of a nylon strand with inherent rigidity, around a bundle of lines, which are then tightened. In addition, there is a cutting device as a mechanical component with two knives for cutting off the ends of the flexible material after tightening, and a drive and control device. In particular, the guide device and the gripping device are activated by a reversible motor, while a cylinder mechanism operated by compressed air is otherwise present. The tightening of the nylon strand as a flexible material takes place in a primary and a secondary process step, in between which a roller mechanism has to be moved relative to the binder. The overall structure is comparatively complicated.

In contrast, the object of the invention is to provide a device which can work with any thread and is simple in construction. For example, for binding motor winding heads, this device should be able to be used in fully automatic operation. In addition, the new device should be usable, in particular, in one-hand operation, without any additional manual steps which have to be carried out in the meantime or subsequently.

According to the invention, the object is achieved by the characterizing features of patent claim 1.

Advantageous further developments are specified in the subclaims.

The invention creates a practical device. A device implemented according to the new device can be held like a pistol by an operator with one hand during the entire workflow and can be guided with its gripper to the desired binding point. Since the binding method implemented as in DE-A-2705418 works discontinuously, but on the one hand the loop end of the twine is cut off after looping and knotting, but on the other hand the continuous end of the twine is caught, a thread that can be unwound from a bobbin can be used. Nevertheless, binding takes place at certain points, for which the device can be freely guided to the wiring harness.

In the device according to the invention, in addition to the latch needle, a cutting knife and a catching needle are guided in such a way that, in chronological succession, the looping and knotting with the latch needle is carried out first, followed by cutting and catching. The tying, knotting, cutting and catching of the thread form a single, completed work cycle. The drive is preferably controlled by compressed air and the control is constructed mechanically. However, an electrical / electronic drive control is also possible.

Further details and advantages of an embodiment of the invention result from the following description of the figures of an embodiment with reference to the drawing in conjunction with the dependent claims.

• Fig. 1 und Fig. 2 den schematischen Aufbau der Gesamtvorrichtung in teilweise geschnittener Ansicht und Draufsicht,
• Fig. 3 einen Teilausschnitt der Fig. 1 in verschiedenen Arbeitsphasen zur Verdeutlichung der Kinematik des Knotvorganges,
• Fig. 4 in Seitenansicht die Führungskulisse für die Zungennadel mit Einstellglied für den Knotvorgang,
• Fig. 5 und Fig. 6 einen Ausschnitt aus den Figuren 1 und 2 in verschiedenen Arbeitsphasen zur Verdeutlichung des Schneidvorganges,
• Fig. 7 und Fig. 8 einen Ausschnitt aus den Figuren 1 und 2 in verschiedenen Arbeitsphasen zur Verdeutlichung des Fangvorganges,
• Fig. 9 und Fig. 10 das verwendete Steuergetriebe in Seitenansicht und Draufsicht,
• Fig. 11 die zur Steuerung des Arbeitszyklus verwendeten Getriebescheiben sowie
• Fig. 12 und Fig. 13 die Einheit zur Druckluftsteuerung in Seitenansicht und Draufsicht.

Show it

• 1 and Fig. 2 shows the schematic structure of the overall device in a partially sectioned view and top view,
• 3 shows a partial section of FIG. 1 in different work phases to illustrate the kinematics of the knotting process,
• 4 is a side view of the guide link for the latch needle with an adjusting member for the knotting process,
• 5 and FIG. 6 shows a detail from FIGS. 1 and 2 in different working phases to illustrate the cutting process,
• 7 and FIG. 8 a section from FIGS. 1 and 2 in different working phases to illustrate the catching process,
• 9 and Fig. 10, the control gear used in side view and top view,
• Fig. 11, the gear discs used to control the work cycle and
• Fig. 12 and Fig. 13, the unit for compressed air control in side view and top view.

The figures show partial areas of the entire device; they are not drawn to one another to scale. In the description of the figures, only the details essential to the invention are discussed.

Identical parts are provided with the same reference symbols in the individual figures. In the description, various references are made to DE-A-2533640, in which the actual binding process is already described so clearly that it will not be discussed in detail below.

1 and 2, 100 denotes the housing of a device for tying parallel lines, such as cable harnesses or the like, which is referred to below as a winding gun. The term “winding gun” already makes it clear that the housing can be held by the user on a housing knob 105 with one hand, brought into the correct working position and put into operation by means of an actuating lever 106. The entire winding gun is so compact that it can be brought into the respective operating position without difficulty even in tight working conditions. It is possible to guide the winding gun along a cable harness manually or mechanically, in particular robot-guided.

The housing 100 of the winding gun essentially consists of two parallel housing plates 110 and 111 which are connected at a distance and on which the working equipment and the necessary operating resources are arranged. At the back, a supply roll for twine can be arranged, from which a thread 2 is brought into the working area on the front part of the housing 100 via corresponding guides. A thread tensioning and return device 120 provides the necessary tension in the thread. The working area is designed with a guide 3 for the thread 2 and a gripper 130 in such a way that a bundle of parallel lines can be wrapped around the thread 2. The gripper 130 is roughly horseshoe-shaped and is guided by a gear transmission. It can be swiveled by approximately ± 90 ° to ensure that a cable harness with its cross section lies in the horseshoe profile. When looping around, the interplay of the gripper 130 with the thread guide 3 and an associated holding needle 4 for the thread is important, which will be described in more detail below. The needle 4 is referred to as a “tongue needle” because of a driving tongue 9 for the thread 2. A forward and backward movement of the latch needle 4 is possible via an associated holder 5 and drive 140 with a compressed air cylinder. Here, the holder 5 of the latch needle 4 is likewise guided in the link, so that, in addition to the higher-level forward and backward movement, there is also a movement in a predetermined curve shape.

When moving the latch needle 4 to loop around a cable harness or parallel lines with twine, it is important that the thread 2 is guided in a defined manner in the work area. For this purpose, corresponding guide plates 131 and 132 are provided on the housing plates 110 and 111 in the area of the gripper 130.

The basic shape of the winding gun, which can be seen in FIG. 1, is essentially known from DE-A-2533640. In this publication, the interaction of latch needle 4 and gripper 130 is described in detail, loops being continuously formed there for looping around the parallel lines. After the looping processes to form a braid along the extensive cable harness, the binding thread must be cut off there and the end of the thread must be knotted manually.

From Fig. 2 it can be seen that the winding gun according to the present patent application has additional equipment that is attached to the side of the housing plate 111. These are essentially a cutting knife 17 and a so-called catch needle 18, both of which can likewise perform a forward and backward movement via a drive 160 with a pressure cylinder. Here, the movement takes place in the direction of the housing plate 111, which can be seen from the groove profile shown.

The pressure medium-actuated drive units 140 and 160 are coupled to one another in the sense of a time delay in the movement sequence, which will be explained further below.

With the cutting knife 17 and the catch pin 18 and the associated operating or control means, it is now possible to carry out the looping process, which was previously carried out continuously along a wire harness, fully automatically discontinuously, including the respective knotting and cutting, so that more can now be tied selectively . The binding is expediently limited to a double looping, which already ensures a sufficient winding strength, whereby in addition to reducing the amount of work involved, considerable material savings can also be achieved.

Based on the known binding process, the kinematics of the knotting, cutting and catching of the thread end will now be explained with reference to FIGS. 3 and 5, 6 and 7, 8. Sub-figures a, b, ... each indicate a significant phase of the corresponding process. Together, these sub-operations result in a complete work cycle.

In FIG. 3, 1 represents an already bound conductor bundle. In addition, 2 identify the binding twine, 3 a thread guide device, 4 the latch needle, 5 the associated holder, 6 the link wheel and 10 the associated link guide. The assignment of these details to FIG. 1 is clearly recognizable. In the individual phases of the knotting process, the position of the associated tongue 9 is indicated for the tongue needle 4.

The device shown is initially used in a manner known per se for tying a wire harness. Here - as described in detail in DE-A-2533640 - the holder 5 is alternately pushed back and forth in the lower or upper groove of the link guide 10, the wrapping in cooperation with the gripper 130 supply of the wire harness with the thread 2 results. The upper guide half of the link guide 10 is blocked for the knot, so that the latch needle 4 can now only move back and forth in the groove of the lower guide half.

3a shows that the thread 2 runs over the thread guide 3 around the line bundle 1 and forms a loop 8 through which the latch needle is guided. The gripper 130 is in the starting position. When the latch needle 4 is moved back with the tongue 9 open, the twine is taken along and pulled as a loop 7 through the last loop 8 present from the binding process. At the same time, the link wheel 6 moves in the opposite direction, so that a position according to FIG. 3b results. The tongue 9 of the latch needle 4 is now closed, which can be achieved by the thread pressure if the latch needle 4 is designed accordingly. This is followed by the reverse movement sequence according to FIG. 3c, the tongue 9 opening when moving forward and the tongue needle 4 then moving through the newly formed loop into a position according to FIG. 3a. Corresponding substeps according to FIGS. 3d and 3e follow, which in principle correspond to the substeps according to FIGS. 3b and 3c, so that the result is a structure with several loops.

It has already been mentioned that for the knotting process the identical equipment of gripper 130 and latch needle 4 as for the binding process is necessary. The only difference is the special movement of the latch needle 4, which is alternately guided above and below the bundle 1 when tying, while the knot has the same movement throughout. This requires a switchable backdrop.

In Fig. 4, the associated link guide is shown in detail: It consists essentially of a holding plate 11 with the guide groove 10 formed in two guide halves, a pin 12 for guiding the holding device 5 for the latch needle 4, a switching tongue 13, a locking lever 14 and a further pin 15. While during the binding process the holding of the latch needle 4 executes such a path, which is described in FIG. 4 by points 1 through 11 to III and from III to 11 to back to 1, path 11 becomes, for example, during the knotting process locked according to III. The pin 12 and the latch needle 4 thus follow the direct path from 1 to 11 and back again from II to I. The latter movement defines a loop which can be tightened to form a knot and can be repeated as required. The setting is blocked by the switching tongue 13, which is pressed upward by the locking lever 14, the locking lever 14 acting directly on the pin 15.

After the knot loops have been laid, the thread 2 of the twine is to be tightened and cut in a defined position, whereby it must be ensured that the cut thread can be caught and is thus immediately available for a new binding process. The kinematics of cutting off on the one hand and catching the thread end on the other hand will be explained in various working phases with reference to FIGS. 5 and 6 on the one hand and FIGS. 7 and 8 on the other hand.

In FIGS. 5 to 8, 16 means the knot to be formed, 17 the cutting knife, 18 the catching needle, 19 the associated holder, 20 a pin on the knife holder, 21 an associated link for guiding the cutting knife 17 and catching needle 18, 22 a compressed air cylinder , 23 a clamping pin, 24 an elbow, 25 a spring, 26 a needle opening and 28 a stop for the catch needle 18th

It is essential that the cutting knife 17 and the catching needle 18 are attached to the jointly guided holder 19 and are coordinated with one another in their movement sequence. The articulated mount 19 with cutting knife 17 and catch pin 18 is moved synchronously by the compressed air cylinder 22.

5a and 6a are in their rest position, FIGS. 5b and 6b show their position immediately after the cutting process. It can be seen that for this purpose the blade 17 is brought along the slide guide 21 into the plane of the latch needle 4, the thread being cut off directly at the knot 16. It is expedient to pull the free end through the knot structure 16 backwards, whereby the catching of the thread end is simplified. For this purpose, the catching needle 18 is present, the shape and function of which becomes clear in detail on the basis of FIGS. 7 and 8. In particular, the sectional view of FIG. 8a shows their comparatively complex structure with inner clamping pin 23, inner spring 25 and an outer pin 27 which is resiliently mounted via an angle piece 24. Here, the clamping pin 23 is firmly connected to the angle 24 and is pressed forward by the spring 25 , so that a thread 2 can be firmly clamped in the needle opening 26. The inner spring pin 27 also serves to support the clamping process.

Due to the interaction of the cutting knife 17 and the catch pin 18, it is now also superfluous to hold the thread at the beginning of the binding process, as was necessary with devices of the prior art. This is the first time that there is a possibility of a fully automated workflow. 6b and 7b in particular illustrate the interaction of latch needle 4, cutting knife 17 and catch needle 18. After cutting, the end of thread 2 is clamped into opening 26 of needle 18. A stop 28 is used to return the clamping device 23 and 24, so that the needle opening 26 is free and the thread 2 can be caught. It is held in place during the subsequent backward movement of the catching needle 18.

From the preceding individual descriptions of the equipment for knotting, cutting and catching the thread, it clearly emerged that the movement sequences for tying, knotting, cutting, catching and holding the twine must be precisely coordinated with one another in terms of time. Suitable control means are necessary in addition to the drive.

The latter can in one embodiment of the Er find in connection with a compressed air drive by a cam control, which is illustrated by the description of FIGS. 9 to 11. The cam control is driven via the link wheel 6, which is rotated in a known manner during the forward and backward movement of the latch needle 4 to the left or right. A drive gear 29, which serves to drive an associated control gear 30, is fastened concentrically to the sliding gear 6. Its fixed axis 31 is screwed to the holding plate 11 of FIG. 4. A freewheel 32 is seated in the axis of the control gear 30, which only permits clockwise rotation of the switching disks 34, 35 and 36, which are jointly attached to a bushing 33. The gear ratio between the gear wheels 29 and 30 is selected such that a working cycle is completed when the switching disk 34, 35 and 36 is rotated through 360 °. This work cycle includes the tying, knotting, cutting and catching or holding process for the twine.

From Fig. 11 it can be seen that the switching disk 34 has sawtooth-shaped notches on the circumference, which have an angular distance of 2x90 ° for a two-time binding process, an angular distance of 2x45 ° for a two-time knotting process and a further 90 ° for the zero position. A spring-loaded pawl 37 can snap into the notches. The pawl 37 is used for the exact fixing of the switching disks 34, 35 and 36 and thus prevents turning back when the directional gear 6 changes direction.

The switching disk 35 in FIG. 11 1 is necessary for the knotting process if, as has been shown above, the blocking of the path 11 to 111 in the link guide 10 is to be effected in the angular range of 2 × 45 °. The lock 14, which is fastened to a lever 38, serves this purpose. The switching disk 36 with pawl 39, on the other hand, is used to stop the binding device. A reversing slide can be blocked via the pawl 39 and the operating function of the device described can thus be stopped.

From FIG. 9 and FIG. 10 it can be seen that the switching disk 34 carries a switching cam 40 which in each case triggers a separate control for the cutting and thread catching process when the winding gun is stopped.

• Bei Bewegung der Schaltnocke 40 nach oben wird gleichzeitig die Schaltklinke 44 nach unten und der Luftdämpfer 41 in Pfeilrichtung betätigt. Nachdem die Schaltnocke 40 den Hebel 44 passiert hat, bewegt sich die Schaltklinke 48 zeitverzögert aufgrund des Luftdämpfers 41 nach oben und betätigt über den Hebel 50 den Steuerkolben 52 nach rechts gegen die Druckfeder 53. Dabei wird der Anschluss 56 mit Druckluft beaufschlagt, der mit dem Druckluftzylinder 22 in der Fig. 6 verbunden ist. Dadurch wird die Vorwärtsbewegung des Schneidmessers 17 und der Fangnadel 18 eingeleitet. Wenn die Schaltklinke 48 über die Nocke 51 läuft, bewegt sich der Steuerkolben 52 aufgrund der Druckfeder 53 nach links. Der Druckluftanschluss 55 wird dann mit Druckluft beaufschlagt und leitet über den Zylinder 22 die Rückstellbewegung des Messers 17 und der Fangnadel 18 ein.

The switching disk 34 with switching cam 40 is in direct operative connection with the compressed air control according to FIGS. 12 and 13. In the latter figures 41 mean a time-delaying air damper, 42 a control valve, 43 a pin with levers 44 mounted thereon, 45 another switching arm, 46 a tension spring, 47 a joint with a pawl resiliently mounted on lever 44. Furthermore, 50 mark a lever mounted at point 49 with a switching cam 51, 52 a control piston on the control valve 42, 53 a compression spring and 54 to 56 compressed air connections. These specified details work together as follows and form a functional unit:

• When the switching cam 40 moves upwards, the switching pawl 44 and the air damper 41 are simultaneously actuated in the direction of the arrow. After the switching cam 40 has passed the lever 44, the switching pawl 48 moves upwards with a time delay due to the air damper 41 and actuates the control piston 52 to the right against the compression spring 53 via the lever 50 Air cylinder 22 is connected in FIG. 6. This initiates the forward movement of the cutting knife 17 and the catch needle 18. When the pawl 48 runs over the cam 51, the control piston 52 moves due to the compression spring 53 to the left. The compressed air connection 55 is then pressurized with compressed air and initiates the return movement of the knife 17 and the catching needle 18 via the cylinder 22.

This completes a work cycle of tying, knotting, cutting and catching the thread. The device is ready for another cycle.

In the device with the various devices described above, it should be emphasized as essential that the work cycle of tying, knotting, cutting and catching the thread is carried out for the first time in individual steps that are precisely coordinated with one another in terms of time. The binding and knotting process, on the one hand, and the cutting and catching process, on the other hand, each have the same effect and are clearly separated from one another.

In the exemplary embodiment described, the drive and control takes place on a pneumatic / mechanical basis. It is also possible to provide the drive electrically and to create an electronic sequence control. A microprocessor system can expediently be used here.

Claims (9)

1. A device for tying a bundle of electrical leads, such as wiring harnesses or the like, by wrapping them in a flexible material which can be drawn off from a spool and which is laid in a plurality of loops, at least one loop of which is wrapped around the bundle, said device having a housing (100) which has a gripping arrangement (130) that can be rotated around the bundle of leads (1), with a horseshoeshaped guide to guide the flexible material (2) around the bundle of leads (1), a a loop-forming arrangement (4, 9, 18) and a cutting arrangement (17) for the flexible material (2), characterised in that

- the gripping arrangement (130) can be rotated by means of gearing (6) with an associated slide guide (10) for a tongued needle (4) for a thread (2) constituting the flexible material, the tongued needle (4) being guided synchronously in the slide guide (10) with two guide halves for the tying operation, and one guide half of the slide guide (10) being locked by means of a lever (14, 15) for the knotting operation;

- the cutting arrangement takes the form of a single cutting knife (17) which is guided so that it can be displaced and pivoted about the longitudinal axis in the same working direction as the tongued needle (4); and

- the cutting knife (17) is provided with a gripping mechanism in the form of a catching needle (18) to hold the thread (2) when it is cut off by the cutting knife (17).

2. A device as claimed in Claim 1, characterised in that the tongued needle (4) can be reversed, on the one hand for the tying operation and, on the other hand for the knotting operation.

3. A device as claimed in Claim 1, characterised in that drive units (140, 160) are present in the housing (100) of the device for coordinated movement of tongued needle (4), cutting knife (17) and catching needle (18).

4. A device as claimed in Claim 3, characterised in that the drive units (140, 160) are provided with a programme control unit (30-40).

5. A device as claimed in Claim 3 or 4, characterised in that for the purposes of carrying out a complete working cycle, the drive units (140, 160) can be controlled as regards the timing of their operation by control cams (34, 35, 36).

6. A device as claimed in Claim 3, characterised in that the drive units (140, 160) are driven by compressed air.

7. A device as claimed in Claim 6, characterised in that in addition to the pressure cylinder for the tongued needle (4), the drive units (140, 160) display a separate reversible pressure cylinder (22) for linear displacement of the cutting knife (17) and catching needle (18).

8. A device as claimed in Claim 1, characterised in that a guide slide (21) is provided to move the cutting knife (17) and catching needle (18) into the plane of the tongued needle (4).

9. A device as claimed in Claim 7, characterised in that the pressure cylinder (22) is provided with a time delay arrangement (41) for precise separation of the tying and knotting operation, on the one hand, and the cutting and catching operation, on the other hand.

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