EP0142001A1 - 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 method for tying a bundle of electrical lines according to the preamble of claim 1 and to an associated device according to the preamble of claim 7.

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 a single 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.

A method and a device of the type mentioned above are specified in detail in DE-OS 25 33 640. With the device described there it is particularly especially possible to machine and continuously wrap a wire harness, with a stability of the thread package created should be achieved by a double thread in each case during the loop formation. However, knotting and cutting off the twine with this device is not possible, so that fully automatic operation is not achieved. The latter peculiarity of the device previously known from DE-OS 25 33 640 is regarded by the experts as disadvantageous since practical work cannot be achieved.

The object of the invention is therefore to provide a method and to create the associated device with which fully automatic operation is now possible, for example when binding motor winding heads. The new device should be able to be used completely in one-hand operation without the need for additional or subsequent manual process steps.

The object is achieved by the characterizing features of claim 1. A device for performing this method is characterized by the characterizing features of patent claim 7.

With the invention, an actually practical method and the associated device are now created for the first time. The device implemented according to the new device can be held like a pistol in one hand during the entire workflow and can be guided to the desired binding point with its gripper the. Since the new process itself works discontinuously, i.e. on the one hand the thread end of the twine is cut off after looping and knotting, but on the other hand the continuous end of the twine is held, binding can be carried out at certain points, for which the device can be freely guided to the cable harness.

In contrast to the stated prior art, the invention does not implement a continuous looping process of the parallel lines, along which the device had to be moved along as evenly as possible, but rather is bound to discrete locations of the lines. This results in much larger possible uses. A continuous crochet structure also had the disadvantage that when the loop was broken at one point, the entire crochet structure was dissolved over the continuous area. In contrast, in the invention, a double looping process with subsequent double knots is preferably carried out at the binding point, the thread end being pulled through the knot structure after cutting to catch. The binding, knotting, cutting and catching of the thread now form a single, completed work cycle.

In the associated device, in addition to the latch needle, a cutting knife and a catching needle are guided in such a way that the looping and knotting with the latch needle and then cutting and catching takes place in chronological succession. 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 the invention emerge from the following description of the figures of an exemplary embodiment with reference to the drawing in conjunction with the patent 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 2 show 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 shows a side view of the guide link for the latch needle with an adjusting member for the knotting process,
• 5 and 6 show a detail from FIGS. 1 and 2 in different work phases to illustrate the cutting process,
• 7 and 8 show a detail from FIGS. 1 and 2 in different working phases to illustrate the catching process,
• 9 and 10 show the control gear used in side view and top view,
• 11 shows the gear discs used to control the work cycle and
• 12 and 13 show the unit for compressed air control in side view and top view.

The figures show partial areas of the entire device; they are not shown to each other 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-OS 25 33 640, in which the actual binding process is already described so clearly that it will not be discussed in detail below.

In FIG. 1 and FIG. 2, 100 denotes the housing of a device for tying parallel lines, such as, for example, cable harnesses or the like, which is referred to below as a winding gun. The designation "winding pistol" already makes it clear that the housing can be held by the user with one hand on a housing knob 105, brought into the correct working position and put into operation via 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. Backwards can be 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 such 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 wire 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 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 equally guided, so that, in addition to the higher-level forward and backward movement, there is also a movement in a predetermined curve shape.

When the latch needle 4 is moved to loop around a wire harness or parallel lines with twine, it is important that the thread 3 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 form of the winding pistol which can be seen in FIG. 1 is essentially known from DE-OS 25 33 640. In this document, the interaction of latch needle 4 and gripper 130 is described in detail, wherein loops for looping the parallel lines are continuously formed there. After the looping processes to form a braid along the extended cable harness, the twine must be cut off there and the end of the thread must be knotted manually.

It can be seen from FIG. 2 that the winding gun according to the present patent application has additional work tools which are 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 in points . The binding is expediently limited to a double looping, which already ensures sufficient winding strength, whereby, in addition to reducing the amount of work involved, considerable material savings can also be achieved.

Starting from the known binding process, the processes of knotting, cutting and catching the thread end are now explained in their kinematics with reference to FIGS. 3, 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 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-OS 25 33 640 - the bracket 5 is alternately pushed back and forth in the lower or upper groove of the link guide 10, the looping of the wire harness with the thread 2 interacting with the gripper 130 results. The upper guide half of the link guide 10 is locked for the knot, so that the latch needle 4 can now only move back and forth in the groove of the lower guide halves.

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 moving the latch needle 4 is at open tongue 9 carried the twine 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 sequence of movements 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 FIG. 3d and FIG. 3e follow, which in principle correspond to the substeps according to FIG. 3b and FIG. 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 connecting link guide is shown in detail: it consists essentially of a mounting plate 11 having formed in two guide halves cam groove 10, a pin 12 for guiding the holding _ß inrichtung, 5 for the latch needle 4, a Umschaltzunge 13, a Locking lever 14 and a further pin 15. While holding the tongues during the binding process needle 4 executes such a path, which is described in FIG. 4 by points I via II to III and from III to II to back to I, path II to III is blocked during the knotting process, for example. The pin 12 and the latch needle 4 thus follow the direct path from I to II and back again from II to I. The latter movement defines a loop which can be tightened into 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, it being necessary to ensure 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 are 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 catching needle 18.

It is essential that the cutting knife 17 and the catch needle 18 on the jointly guided bracket 19 is are brought and are coordinated in their movement. 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, FIG. 5b and FIG. 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 from 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 cutting knife 17 and catch needle 18, it is now also superfluous to hold the thread at the beginning of the binding process, as was necessary in the case of devices of the prior art. This is the first time that there is a possibility of a fully automated workflow. FIG. 6b and FIG. 7b in particular illustrate the interaction of latch needle 4, cutting Knife 17 and catch needle 18. After cutting, the end of the thread 2 is clamped into the opening 26 of the 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 when 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 be done in one embodiment of the invention in connection with a compressed air drive by a cam control, which is illustrated by the description of FIG. 9 to FIG. 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 allows clockwise rotation of the switching disks 34, 35 and 36 which are jointly fastened on a bushing 33. The translation between the gears 29 and 30 is selected so that a working cycle is completed when the disks 34, 35 and 36 are rotated through 360 °. This working cycle includes the binding, knotting, cutting and catching or holding process for the twine.

From FIG 11 it can be seen that the switching disc 34 saw-toothed at the circumference notches that an angular distance of 2 x 90 ° for a two-time binding operation, an angular distance of 2 x 45 ° for a two-time node operation and another 90 ⁰ hold 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 is necessary for the knotting process if, as has been shown above, the blocking of the path II to III 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 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 FIG. 12 and FIG. 13. In the latter figures 41 mean a time-delaying air damper, 42 a control valve, 43 a pin with levers 44 attached to it, 45 another switching arm, 46 a tension spring, 47 a joint on the lever 44 spring-loaded pawl. 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 interact 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 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 Compressed 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 acted upon by compressed air and initiates the return movement of the knife 17 and the catch 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 precise for the first time coordinated individual steps is carried out. 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 (16)

1. A method for tying a bundle of electrical lines, such as wire harnesses or the like, by looping with a thread that can be pulled off a spool and that is laid in several loops, of which at least one loop is looped around the bundle, one further loop each placed in the opposite direction around the bundle and, in order to fix a loop, the following loop is pulled through the previous loop, which process can be repeated, characterized in that after a predetermined number of repetitions of the looping process, a knot is formed in the thread by laying additional loops and that the thread is cut off at the knot, with the subsequent end of the thread being held and immediately available for performing a new binding process. 2. The method according to claim 1, characterized in that the wrapping process is repeated once, so that the bundle is bound twice by the thread. 3. The method according to claim 1, characterized in that at least two further loops are placed for knot formation. 4. The method according to claim 3, characterized in that the knot formation takes place by contracting the further loops. 5. The method according to claim 1, characterized in that the thread is cut immediately in the last loop and the end of the thread is drawn through the loops forming the knot to catch. 6. The method according to claim 1, characterized in that tying, knotting, cutting and catching the thread form a closed work cycle. 7. The device for carrying out the method according to claim 1 or one of claims 2 to 6, with a housing on which a supply spool for a thread and a rotatable around the cable bundle gripper are arranged with a horseshoe-shaped guide for guiding the thread around the cable bundle and which has a loop-forming device with a tongue needle movable in the guide of the gripper for wrapping the bundle with the thread, characterized in that in addition there is a cutting knife (17) which can be moved in the same working direction as the tongue needle (4) about the longitudinal axis and is pivotally guided, and that the cutting knife (17) is assigned a catch needle (18) for holding the thread (2) when cutting by the cutting knife (17). 8. The device according to claim 7, characterized in that the latch needle (4) for the binding process on the one hand and knotting process on the other hand is reversible. 9. The device according to claim 7, characterized in that the gripper (130) by means of a gear mechanism (6) with associated link guide (10) for the latch needle (4) can be rotated, the latch needle (4) for the binding process synchronously in the link guide (10) guided with two guide halves and one guide half of the link guide is locked by means of a lever (14, 15) for the knotting process. 10. The device according to claim 7, characterized in that in the device housing (100) drive units (140, 160) for the coordinated movement of tongue needle (4), cutting knife (17) and catch needle (18) are available. 11. The device according to claim 10, characterized in that the drive units (140, 160) is assigned a program control unit (30 - 40). 12. The apparatus of claim 10 or 11, characterized in that the drive units (140, 160) by control disks (34, 35, 36) in the sense of carrying out a complete working cycle in their timing can be controlled. 13. The apparatus according to claim 10, characterized in that the drive units (140, 160) are compressed air driven. 14. The apparatus according to claim 13, characterized in that the drive units (140, 160) in addition to the pressure cylinder for the latch needle (4) have a separate switchable pressure cylinder (22) for linear displacement of the cutting knife (17) and catch needle (18). 15. The apparatus according to claim 7, characterized in that a guide link (21) is provided for the purpose of transferring the cutting knife (17) and catch needle (18) into the plane of the latch needle (4). 16. The apparatus according to claim 14, characterized in that the pressure cylinder (22) is associated with a time delay device (41) for the exact separation of binding and knotting process on the one hand and cutting and catching process on the other.

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