EP0534106B1 - Device for applying grommets to electrical cables - Google Patents

Description

The invention relates to a device for the fitting of electrical cables, with an open at least on one end face, filled with grommets, which can be driven about an axis extending obliquely to the horizontal, with blades arranged inside the drum and with a protruding into the drum Feeding device, the spouts being transferred to the feeding device for further processing by means of the blades when the drum is rotating.

With such devices, grommets, which are required, for example, for the passage of electrical cables through housing walls of electrical apparatus, can be pushed onto the cables in an efficient manner.

In the case of a device known from a publication 7.132.1, July 1991, from the company KOMAX AG, Dierikon / CH, the nozzles are fed through conveyor pots with spiral tracks, the nozzles often having to be talked, which can lead to soiling and where different conveyor pots are required for each type of nozzle. For the purpose of assembly, the grommet is held firmly in a gripper and the cable is inserted into the grommet bore. This generally achieves good results, although large differences in the grommet position on the cable can occur with different types of cable, such as insulation diameter and surface quality. Furthermore, only grommets can be processed that can be held and supported perfectly by the gripper due to their shape and dimensions. Another type of assembly is described in German utility model G 89 09 515.4. Here, one is held in a swivel finger in the bore Sealing plug pushed a pusher pin. Then a plunger sleeve slidingly arranged on the plunger pin pushes the sealing plug from the plunger pin onto an electrical cable. With this method, certain requirements are placed on the shape and dimensions of the sealing plugs, since there must be a sufficiently large contact surface on them.

US-A-3 349 891 discloses a device by means of which uniformly shaped parts can be brought into a specific position required for further processing. In this case, a storage drum is provided, in which the uniformly shaped parts are located, and which can be driven about an axis running obliquely to the horizontal. Arranged in the storage drum is also a rail inclined to the horizontal, which is designed such that when the storage drum is rotated, a number of parts are caught by the rail and remain in the desired position. Due to the force of gravity, the parts slide off the rail, whereby, bridging an air gap, they are always caught by a conveyor pipe with the same end first.

The invention has for its object to provide a device referred to in the introduction, in which the disadvantages arising from conveyor pots with spiral tracks are avoided and in which the spouts can have a shape which is independent of the type of assembly and the nature of the cable in the exact positioning the spout does not matter.

This object is achieved by the invention characterized in claim 1. Here, a conveyor rail of the feed device has a buffer in which the spouts are stored in the correct position. Aligned with the axis of a vertical hole made under the first grommet in the buffer is a separating cylinder with a mandrel that can be moved up and down, and above the conveyor rail A swiveling assembly cylinder with a grommet receiving part seated on a piston rod is arranged below the conveyor rail, the grommet being pushed through the vertical bore into the grommet receiving part by means of the mandrel and the assembly cylinder being pivoted into a horizontal position. Pivotal gripper jaws then encompass the grommet receiving part and form a further borehole running centrally with the grommet bore. The gripper jaws and the piston rod and the electrical cable to be fitted are then moved relative to one another, the grommet being applied to the electrical cable centered through the further bore and an overpressure building up in the grommet receiving part.

• Es können lose Tüllen mit minimaler Vorbehandlung verarbeitet werden, insbesondere müssen die Tüllen nicht getalkt werden, so dass keine grösseren Verschmutzungen entstehen können.
• Die Zuführeinrichtung unterscheidet sich für verschiedene Tüllentypen nur durch die Form der Förderschiene. Alle übrigen Teile bleiben grösstenteils gleich.
• Die erfindungsgemässe Förderschiene stellt eine einfache kompakte Lösung für die Funktionen Fördern, Sortieren und Speichern dar, die auch bei grösseren Fördergeschwindigkeiten zuverlässig arbeitet. Durch die Überwachung mittels Lichtschranke und das programmgesteuerte Ausblasen der Förderschiene werden die meisten Zuführstörungen selbststätig behoben.
• Die transparente Trommel ermöglicht eine optische Kontrolle des Tüllenvorrates und des Zuführvorganges.
• Gegenüber den im Stand der Technik erwähnten Fördertöpfen, können auch längere, schlankere Tüllen störungsfrei verarbeitet werden.
• Beim Aufschieben der Tülle auf das Kabel ergibt sich durch den im Tüllenaufnahmeteil herrschenden Überdruck eine kleinere Einschiebekraft und damit eine Reduktion der Knickgefahr für das Kabel. Ausserdem wird die Tülle spielfrei gelagert und beim Aufschieben weniger deformiert, so dass eine genauere Positionierung auf dem Kabel erreicht wird.
• Die Bestückungseinrichtung kann auf einfache Weise an verschiedene Tüllentypen angepasst werden, ohne dass an Form und Abmessungen der Tüllen besondere Anforderungen gestellt werden müssen.
• Mit dem im Bestückungsvorgang integrierten Abziehen des Isolationsrestes wird ein zusätzlicher Arbeitsgang zum Abisolieren der Kabelenden gespart.

The advantages described below are achieved with the invention.

• Loose grommets can be processed with minimal pretreatment; in particular, the grommets do not have to be talked, so that no major contamination can occur.
• The feed device differs for different types of grommets only in the shape of the conveyor rail. All other parts remain largely the same.
• The conveyor rail according to the invention represents a simple, compact solution for the functions of conveying, sorting and storing, which works reliably even at higher conveying speeds. The monitoring by means of a light barrier and the program-controlled blowing out of the conveyor rail automatically remedies most feeding problems.
• The transparent drum enables an optical control of the spout supply and the feeding process.
• Compared to the conveyor pots mentioned in the prior art, longer, slimmer spouts can also be processed without problems.
• When pushing the grommet onto the cable results from the overpressure prevailing in the sleeve receiving part means a smaller insertion force and thus a reduction in the risk of kinking the cable. In addition, the grommet is stored without play and less deformed when pushed on, so that a more precise positioning on the cable is achieved.
• The equipment can be easily adapted to different types of grommets, without having to make any special demands on the shape and dimensions of the grommets.
• With the removal of the insulation residue integrated in the assembly process, an additional operation for stripping the cable ends is saved.

Fig. 1

eine teilweise geschnittene Ansicht der erfindungsgemässen Einrichtung,

Fig. 2

eine Ansicht eines Teiles der Einrichtung gemäss Fig. 1 in Pfeilrichtung A,

Fig. 3

eine Förderschiene der Einrichtung gemäss Fig. 1 in perspektivischer Darstellung und grösserem Massstab,

Fig. 4

eine Tüllen-Bestückungsanordnung der Einrichtung gemäss Fig. 1 mit der Förderschiene gemäss Fig. 3 in perspektivischer Darstellung und grösserem Massstab,

Fig. 5a- 5e

verschiedene Querschnitte der Förderschiene gemäss Fig. 3 mit Darstellung des Sortiervorganges der Tüllen,

Fig. 6a- 6d

einen Längsschnitt des Endes der Förderschiene gemäss Fig. 3 mit Darstellung des Vereinzelungsvorganges der Tüllen,

Fig. 7a- 7f

eine Darstellung des Bestückungsvorganges der Tüllen und

Fig. 8a- 8g

die Darstellung einer Variante des Bestückungsvorganges der Tüllen.

The invention is explained in more detail below with reference to an exemplary embodiment shown in the drawing. Show it:

Fig. 1

2 shows a partially sectioned view of the device according to the invention,

Fig. 2

2 shows a view of part of the device according to FIG. 1 in the direction of arrow A,

Fig. 3

1 in a perspective view and on a larger scale,

Fig. 4

1 with the conveyor rail according to FIG. 3 in a perspective view and on a larger scale,

Figures 5a-5e

3 shows different cross-sections of the conveyor rail according to FIG. 3, showing the sorting process of the spouts,

6a-6d

a longitudinal section of the end of the conveyor rail according to FIG. 3 showing the Separation process of the grommets,

Figures 7a-7f

a representation of the assembly process of the spouts and

8a-8g

the representation of a variant of the assembly process of the spouts.

In Fig. 1, 1 denotes a machine frame, on which a drum 2 is rotatably mounted obliquely about an axis 3 extending to the horizontal by means of a thin ring bearing 4. At the lower end of the drum 2, a filling funnel 5 is arranged on the machine frame 1, through which spouts provided for the fitting of electrical cables are filled into the drum 2, which is open on the front side. The drum 2 is driven by means of an air motor 6 via a friction wheel 7 (FIG. 2), the speed of the drum 2 being able to be set by means of a throttle (not shown). In the interior of the drum 2, blades 8 are fastened at the lower end, by means of which the filled spouts can be fed to a conveyor rail 9 which projects into the drum 2 through the open end face at the higher end. The drum 2 is preferably made of transparent plastic, so that an optical check of the spout supply and the feeding process is possible. The conveyor rail 9 described in more detail below with reference to FIG. 3 is fastened on a linear vibratory conveyor 10 which is arranged on a part 11 of the machine frame 1. A light barrier 12, which is also attached to the machine frame 1, monitors the function of the conveyor rail 9. 13 denotes a separating cylinder and 14 an assembly cylinder of a nozzle assembly arrangement attached to the machine frame 1, which is described in more detail below with reference to FIG. 4. An electrical feed from a cable processing machine, not shown, to the grommet assembly Cable 15 has already been pre-processed so that the insulation is already cut, but the rest of the insulation 15.1 is still on the end of the cable to protect the strand.

3, the conveyor rail 9 has a groove 16 in the longitudinal direction, the cross section of which corresponds approximately to the outline of the longitudinal section of a spout 17 (FIG. 5a). The groove 16 is open at the rear end 18 of the conveyor rail 9, while it is closed at the front end 19 (FIGS. 6a-6d). The front part of the groove 16 in the conveying direction (arrow, FIG. 3) serves as a buffer 20, in which the spouts are stored in the correct position and which is covered with a cover plate 21. The cover plate 21 covers the groove 16 in half, so that the stored spouts are visible. At the buffer inlet, the cover plate 21 has a projection 21.1 which completely covers the groove 16. The front end 19 of the conveyor rail 9 is covered with a plate 22 in which a bore 23 is provided, the axis of which coincides with the axis of the first spout in the buffer 20. Below the first spout in the buffer 20 there is a vertical bore 24 (FIGS. 6a-6d) in the conveyor rail 9, the axis of which also coincides with the axis of the first spout and the diameter of which is smaller than that of the spout 17. In front of the buffer inlet, a sorting baffle 25 is provided with a recess 26 interrupting the groove 16 on one side and a blow-out nozzle 27 (FIG. 5c). With 28 a blow-off nozzle arranged in front of the sorting baffle 25 is designated. Behind the buffer inlet, the light barrier 12 (not shown) (FIG. 1) is connected, the light beam of which is symbolized by a dash-dotted line 29.

4, the separating cylinder 13 is arranged above the conveyor rail 9 in the axis of the one bore 23 (FIG. 3) and the vertical bore 24 (FIGS. 6a-6d). The separating cylinder 13 has an up and down movable mandrel 30. Below the conveyor rail 9, the loading cylinder 14 is in the vertical axis Bore 24 arranged in a continuous manner. The loading cylinder 14 is pivotally mounted and has a piston rod 31 on which a grommet receiving part 32 is arranged. A bore 32.1 (Fig. 6a-6d) for receiving the spout 17 is connected to a compressed air source, not shown, so that a vacuum or overpressure can be generated inside the spout receiving part 32. A first and a second angular gripper 34, 35 are arranged on a head 33 which can be moved back and forth in the double arrow direction. The first angular gripper 34 has two pivotable gripper jaws 34.1, 34.2 which, after being pivoted in, can comprise the spout receiving part 32 and form a further bore 36 (FIGS. 7b, 7c) running centrally with the spout bore. The second angle gripper 35 has two pivotable knives 35.1, 35.2, by means of which the insulation residue 15.1 (FIGS. 7a-7f) can be removed from the cable end after the pivoting-in.

The device described above works as follows:
The spouts 17 poured into the filling funnel 5 enter the drum 2, whereby they are conveyed upward by the blades 8 when the drum 2 rotates and partially fall onto the rear end of the conveyor rail 9. Here, only a part of the spouts 17 is in the correct position (FIG. 5a). The conveyor rail 9 set in vibration by the linear vibratory conveyor 10 now conveys the spouts 17 in the direction of the higher end of the drum 2. The spouts reach the blow-off nozzle 28, where all the spouts that are on the conveyor rail 9 or at an angle on the groove 16 pass through a continuous, adjustable air flow is blown off and fall back into the drum 2 (Fig. 5b). In the sorting baffle 25, spouts 17 which are upside down or lie in the groove 16 are blown out through the recess 26 by means of the blow-out nozzle 27 (FIG. 5c). Should an incorrectly located spout in the sorting chicane 25 not be blown out, it remains hang on the protrusion 21.1 of the cover plate 21 at the buffer entrance (Fig. 5d). Here, the continuous conveyance of the spouts 17 (FIG. 5e) in the correct position in the buffer 20 is interrupted, so that the light barrier 12 causes the sorting baffle 25 to be blown out by means of a further blow-out nozzle 27.1 (FIG. 5d) by means of a short, powerful compressed air pulse.

In each case the foremost spout in the buffer 20 comes to be above the vertical bore 24 (FIG. 6a). Due to the vertical movement of the mandrel 30 moved by the separating cylinder 13 (FIG. 4), the spout is pushed through the vertical bore 24 into the spout receiving part 32 (FIG. 6b). The bore 32.1 in the grommet receiving part 32 is now evacuated, so that the grommet remains securely in the grommet receiving part 32 during the subsequent upward movement of the mandrel 30 (FIG. 5c). Due to the movement of the conveyor rail 9, the next grommet has now taken the place at the separating point above the vertical bore 24 (FIG. 6d). At the same time, the loading cylinder 14 (FIG. 4) swivels into the horizontal position, the vacuum in the nozzle receiving part 32 preventing the nozzle from falling out.

After the assembly cylinder 14 has been pivoted into the horizontal position, the grommet receiving part 32 runs coaxially with the cable 15 (FIG. 7a). Now the first angular gripper 34 is closed, so that the gripper jaws 34.1, 34.2 encompass the grommet receiving part 32 (FIG. 7b). So then the bore 32.1 is supplied with compressed air, with which it can be determined whether there is a spout in the spout receiving part 32. Then the loading cylinder 14 with the piston rod 31 and the head 33 with the angular grippers 34, 35 (FIG. 4) simultaneously move against the cable 15, as a result of which the grommet 17 is pushed onto the cable 15 (FIG. 7c). Here, the further bore 36 formed by the gripper jaws 34.1, 34.2 serves as a centering and guide for the cable 15.

During the slide-on process, the bore in the grommet 17 is closed by the cable 15, as a result of which an overpressure can build up in the grommet receiving part 32, by means of which an exact position of the grommet 17 on the cable 15 is achieved. Then the piston rod 31 (FIG. 4) moves back with the grommet receiving part 32 into the starting position and the gripper jaws 34.1, 34.2 are opened (FIG. 7d). Now the second angular gripper 35 is closed and the insulation residue 15.1 is held between the knives 35.1, 35.2 (FIG. 7e). At the same time, the loading cylinder 14 swings back into the vertical position with the grommet receiving part 32 and is ready for the next separating process. The head 33 then moves back to the starting position with the angular grippers 34, 35 (FIG. 4), the insulation residue 15.1 being removed from the cable 15 (FIG. 7f) and, when the knives 35.1, 35.2 are subsequently opened, a waste container (not shown) is handed over.

8a-8g, the cable is moved to the grommet, as a result of which the cycle time can be shortened. Here, the angular gripper 34 with the grommet receiving part 32 is already in a fixed assembly position while the electrical cable 15 is still being fed, so that it can be pushed immediately into the grommet 17 (FIGS. 8a, 8b). Then the piston rod 31 (FIG. 4) moves back with the grommet receiving part 32 into the starting position and the gripper jaws 34.1, 34.2 are opened (FIG. 8c). Now the second angle gripper 35 is closed and the insulation residue 15.1 is held between the knives 35.1, 35.2 (FIG. 8c). Then the assembly cylinder 14 with the grommet receiving part 32 swings back into the vertical position and the electrical cable 15 with the grommet 17 is withdrawn, the insulation residue 15.1 being removed (FIG. 8d). The head 33 then moves back with the angular grippers 34, 35 (FIG. 4) to the starting position (FIG. 8e). The next time you open it the knife 35.1, 35.2 the insulation residue 15.1 falls off, and the grommet receiving part 32, which has meanwhile been filled again with a grommet 17, is again moved between the gripper jaws 34.1, 34.2 and clamped for a new fitting process (FIGS. 8f, 8g).

Claims (8)

1. Equipment for the fitting of grommets to electrical cables, with at least one drum (2), which is open at one end face, filled with grommets (17) and which is drivable about an axis (3) extending inclined to the horizontal, with scoops (8) arranged in the interior of the drum (2) and with a feed equipment projecting into the drum (2), wherein - while the drum (2) is rotating - the grommets (17) are transferred by means of the scoops (8) to the feed equipment for the purpose of further processing, characterised thereby,

   - that the feed equipment displays a conveying rail (9), in which a buffer store (20) is provided, in which the grommets (17) are stored, that have been taken from the drum (2) and been brought into a certain position,

   - that a vertical bore (24) is provided in the conveying rail (9) below the first grommet (17) stored in the buffer store (20),

   - that a singling cylinder (13) with a punch (30) that is movable up and down is arranged above the conveying rail (9) and extending in the axis of the vertical bore (24),

   - that a pivotable equipping cylinder (14) with a grommet-receiving part (32) sitting on a piston rod (31) is arranged below the conveying rail (9) and extending in the axis of the vertical bore (24),

   - wherein one grommet (17) is pushed each time through the vertical bore (24) into the grommet-receiving part (32) by means of the punch (30) of the singling cylinder (13) and the actuating cylinder (14) pivots into an horizontal position,

   - that a first angle gripper (34) is provided, which displays pivotable gripper cheeks (34.1, 34.2), which after inward pivotation encompass the grommet-receiving part (32) and form a further bore (36) extending centrally with the grommet bore and

   - that the first angle gripper (34) as well as the piston rod (31) of the equipping cylinder (14) and the electrical cable (15) to be equipped are moved one relative to the other while the grommet (17) is pushed onto the electrical cable (15), which is centred by the further bore (36), until the required position is reached.
2. Equipment according to patent claim 1, characterised thereby, that the electrical cable (15) is pushed into the grommet (17) while the angle gripper (34) disposed in the equipping position and the grommet-receiving part (32) are stationary.
3. Equipment according to patent claim 1, characterised thereby, that the angle gripper (34) with the grommet-receiving part (32) is moved against the stationary electrical cable (15) disposed in the equipping position, while the grommet (17) is pushed onto the electrical cable.
4. Equipment according to patent claim 1, characterised thereby, that the ends of the cables (15) to be equipped are partially stripped of their insulation and the insulation remnant (15.1) sits on the cable ends and that a second angle gripper (35) is provided, which displays pivotable blades (35.1, 35.2), wherein the blades (35.1, 35.2) - after the retraction of the piston rod (31) and the grommet-receiving part (32) as well as the opening of the gripper cheeks (34.1, 34.2) - pivot inwardly and clamp in the insulation remnant (15.1) so that the insulation remnant (15.1) is drawn off from the cable end on relative movement of the angle grippers (34, 35) against the cable (15).
5. Equipment according to patent claim 2, characterised thereby, that the grommet-receiving part (32) displays a bore (32.1), which is matched to the grommet (17) and connected with a source of compressed air, wherein the grommet (17) after insertion into the grommet-receiving part (32) is retained by vacuum and the presence of a grommet (17) in the grommet-receiving part (32) is checked before the introduction of the cable (15) by excess pressure, wherein the excess pressure remains maintained until the grommet (17) has reached the required position on the cable (15).
6. Equipment according to patent claim 1, characterised thereby,

   - that the conveying rail (9) in the longitudinal direction displays a groove (16), the cross-section of which corresponds approximately to the outline of the longitudinal section of a grommet (17),

   - that that part of the groove (16), which is forward in conveying direction, serves as buffer store (20), which is covered in such a manner by means of a metal cover plate (21) that only grommets (17) in correct position can run into the buffer store (20),

   - that a sorting baffle (25) with a cut-out (26) interrupting the groove (16) at one side and an ejector nozzle (27) is provided before the buffer store inlet,

   - that an ejector nozzle (28) is arranged before the sorting baffle (25) and

   - that a light barrier, which monitors the continuous inflow of the grommets (17) into the buffer store (20), is arranged behind the buffer store inlet, wherein a further ejector nozzle (27.1) is provided, which opens into the sorting baffle (25).
7. Equipment according to patent claim 1, characterised thereby, that the diameter of the vertical bore (24) in the conveying rail (9) is smaller than the diameter of the grommet (17).
8. Equipment according to patent claim 1, characterised thereby, that the drum (2) is made of transparent synthetic material.

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