Rotary stripping device for electrical cables in general, in particular for coaxial cables

Abstract

Rotary stripping device for electric cables in general, particularly for coaxial cables, comprising a front assembly (5) for supporting the stripping blades (7) of said cable (1), a shaft (6) for operating the aforementioned blades (7) and a rear assembly (8). A motor (9) and belt (10) system is provided to rotate the aforementioned complex of the front assembly (5) with cover (11), the rear assembly (8), and the shaft (6). In the stripping device of the invention, the rear assembly (8) rotates the aforementioned shaft (6) relative to the front blade holder assembly (5), thus varying the relative distance between the stripping blades (7) of the cable (1). Compared to the rotary stripping devices of the prior art, the one according to the invention offers the advantage of having limited overall dimensions, allowing its use in conjunction with conventional units for crimping metal terminals on the stripped end of the coaxial cable.

Description

[0001] ROTARY STRIPPING DEVICE FOR ELECTRICAL CABLES IN GENERAL, IN PARTICULAR FOR COAXIAL CABLES

[0002] DESCRIPTION

[0003] BACKGROUND OF THE INVENTION

[0004] The present invention relates to a rotary stripping device for electric cables in general, particularly for coaxial cables.

[0005] The field of the invention relates to systems used to strip, or remove the external sheath of electric cables, particularly of coaxial cables, in order to expose the metal part thereof conductive of electrical signals, data signals and the like.

[0006] In this kind of applications, the coaxial cable consists of an inner metal core, usually made of copper, surrounded by one or more insulating layers, whose function is to isolate the metal and filter various frequencies of the signals to be transported to the exterior of the cable.

[0007] In order to strip coaxial cables, stripping devices are currently known, wherein cutting of the external insulating layer is carried out by a rotating blade unit, whose blades hack the coaxial cable at the end thereof to be stripped.

[0008] The described known solutions, however, have the drawback of being very bulky as a whole, which hinders their use on semi-automatic bench machines. In fact, the spaces required to associate or integrate the stripping devices on the units for crimping the metal terminal to the conductive end of the coaxial cable, are very limited.

[0009] The publication DE 102020207962 A1 discloses a four-blade device for processing the terminals of electric cables.

[0010] The publication US2022 / 0392447A1 discloses a circular cutting unit for multilayer wires.

[0011] The publication US2020 / 0076174A1 concerns a stripping device with a movable disk for controlling the movement of the blades. SUMMARY OF THE INVENTION

[0012] The main aim of the present invention is therefore to provide a rotary stripping device for electric cables in general, particularly for coaxial cables, which, unlike similar devices of the prior art, has dimensions sufficiently compact to allow its use on the crimping units of standard bench machines.

[0013] These and other objects are achieved with the stripping device of claim 1. Preferred embodiments of the invention result from the remaining claims.

[0014] Compared to the rotary stripping devices of the prior art, the one according to the invention offers the advantage of having limited dimensions, allowing its use in conjunction with conventional units for crimping metal terminals on the stripped end of the coaxial cable.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] These and other objects, advantages, and features result from the following description of a preferred embodiment of the device of the invention, illustrated, by way of non-limiting example, in the figures of the attached drawings.

[0017] In them:

[0018] - Figure 1 illustrates an example of a coaxial cable suitable to be stripped by the device of the invention;

[0019] - Figure 2 illustrates with an overall perspective view the stripping device of the invention;

[0020] - Figure 3 illustrates the device in Figure 2, with a view of the stripping blades and their respective drive cams;

[0021] - Figure 4 illustrates the device in Figure 2 in longitudinal section;

[0022] - Figure 5 illustrates with an exploded view the device in Figure 2;

[0023] - Figure 6 illustrates with a perspective view the blade assembly of the device in Figure 2.

[0024] - Figure 7 illustrates the rotation assembly of the blade drive shaft of the device in Figure 2;

[0025] - Figure 8 illustrates with a perspective view the blade drive shaft of the device in Figure 2;

[0026] - Figure 9 illustrates the transmission of the rotational motion to the blade assembly system, shaft rotation assembly, and blade drive shaft of the device in Figure 2;

[0027] - Figures 10 and 11 illustrate the details of the rotational movements of the shaft and blade holder assembly in Figure 9;

[0028] - Figures 12, 12A, and 16 illustrate the positioning of the blades of the device in the previous Figures, in the initial fully open or resting phase;

[0029] - Figures 13, 13A, 14, 14A, 17, and 18 illustrate the positioning of the blades of the device in the previous Figures, corresponding to two different degrees of stripping of the electric cable; and

[0030] - Figures 15, 15A, and 19 illustrate the positioning of the blades of the device in the previous Figures, in the final cutting phase of the electric cable.

[0031] DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0032] The coaxial cable 1 in Figure 1 consists of an inner conductive metal part 2, coated with one or more outer insulating layers 3.

[0033] In order to strip, even selectively, the metal part 2 of the coaxial cable 1 by removing the outer insulator 3, the device of the invention, indicated as 4 in Figure 2, is used.

[0034] The stripping device 4 comprises a front blade holder assembly 5, on which are coaxially arranged a shaft 6 for operating two stripping and cutting blades 7 for the cable 1 , and a rear rotation assembly 8 for rotating the shaft 6 relative to the front blade holder assembly 5.

[0035] As shown in Figure 4, the front assembly 5 is frontally closed, above the blades 7, by means of a blade holder cover 11 , which is in turn fastened to the same assembly 5 by means of screws 25.

[0036] The complex formed by the front assembly 5, frontally closed by a cover 11 for the sliding housing of the blades 7, by the shaft 6, and by the rear assembly 8 is rotated, as a whole, by means of a motor 9 with a corresponding transmission belt 10. The front assembly 5, equipped with the stripping and cutting blades 7 for the cable 1 , receives the rotational motion from the belt 10 and the corresponding motor 9.

[0037] This rotational motion is in turn transmitted to the rear assembly 8 by the sliding engagement of pins 12 of the latter within respective longitudinal seats 13 of the same front blade holder assembly 5.

[0038] As illustrated in Figures 2 and 7, the rear assembly 8 is linearly moved, relative to the front blade holder assembly 5, by means of an actuator or controlled electronic axis 23, sliding on a corresponding straight guide 24.

[0039] Among the electronic axes suitable for the invention, a cited example is the LEY16C-30B-R3AP1 model by SMC ITALIA spa (IT), equipped with a movable rod fixed to the joint 28 in Figure 7. The joint 28, in turn, is mounted fixedly on the rear assembly 8, for its translation along the guide 24. On the opposite side, the electronic axis 23 is fixed to the front assembly 5 of the stripping device.

[0040] In Figure 8, the drive shaft 6 of the blades 7 of the front assembly 5 is illustrated, consisting of a stem 14 with an external surface that has a helical groove or slot 15, within which one or more balls 16 are slidably housed which, in turn, are fixed to the rear assembly 8 of the stripping device 4 by means of respective locking dowels 17.

[0041] At the end of the stem 14 of the shaft 6, which is inserted in the front blade holder assembly 5, a disc-shaped body 18 with cam seats 19 is provided integral with the same shaft 6.

[0042] As shown in Figure 12A, the blade holder cover 11 has a seat 20 for the sliding housing of supports 21 , which are fixed to the respective blades 7. Additionally, there are two pawls 22, one for each blade 7, fixed to their respective supports 21 and protruding from them.

[0043] When the shaft 6 is assembled within the front assembly 5, which has the corresponding blade holder cover 11 fixed, the pawls 22 are slidably housed within the hollow seat 18a of the aforementioned disc-shaped body 18 of the shaft 6. On the inner edge of the same seat 18a, two sliding guide cams 19 are also provided for the respective pawls 22 of the blades 7 (Figures 4, 12-15).

[0044] As shown in Figure 9, the rotation imparted by the motor 9 and belt 10 system to the front assembly 5 is also transmitted to the rear assembly 8 of the stripping device 4, by the coupling of pins 12 of the same assembly 8 within the respective seats 13 of the assembly 5.

[0045] In turn, the shaft 6 and the corresponding disc-shaped body 18 receive the corresponding rotational movement, relative to the front assembly 5 equipped with blade holder cover 11 , by the engagement of the system of dowels 17 and balls 16, which are attached to the rear assembly 8, within the groove 15 of the stem 14 of the same shaft 6.

[0046] The sliding of the pawls 22 against the respective cams 19 of the discshaped body 18, in turn, causes the blades 7 to move apart and come closer to each other, creating a jaw-like relative movement due to their alignment with opposing ends (Figures 17-19).

[0047] As illustrated in Figures 12, 12A, and 16, in the initial resting position which corresponds to the maximum distance between the blades 7, the pawls 22 are housed within the seat 18a with cams 19 of the disc-shaped body 18 of the shaft 6.

[0048] In this initial condition, the system of balls 16 and dowels 17 is located at position L0 within the helical groove 15 of the stem 14 of the shaft 6. Additionally, the pawls 22 are arranged on the initial axis X0, corresponding to an angle a0 of blade 7 orientation on the disc-shaped body 18 of the shaft 6. In this position, the blades 7 have a maximum mutual distance DO (Figure 16).

[0049] In the next phase, illustrated in Figures 13, 13A, and 17, the controlled axis 23 linearly moves the rear assembly 8 from the initial position L0 to the new position L1. In this way, by the engagement of the balls 16 within the groove 15 of the stem 14 of the shaft 6, the latter is rotated relative to the front assembly 5, equipped with the blade holder cover 11 fixed to the same assembly 5 by means of screws 25 (arrow F1 in Figure 13 and Figure 13A).

[0050] As a result, the cams 19 present on the disc-shaped body 18 of the stem 14 of the shaft 6 are rotated from the initial position on axis X0 to a position X1 , traveling through an angle a1 greater than a0. This movement, in turn, causes the pawls 22 of the cover 11 to come closer together, correspondingly moving their respective blades 7 along axis X0, going from the maximum distance DO to a distance D1 smaller than DO (Figure 17).

[0051] Continuing in its linear movement, the controlled electronic axis 23 brings the assembly of dowels 17 and balls 16 to the position L2 in Figure 14, with the balls 16 sliding within the groove 15 of the stem 14 of the shaft 6.

[0052] This linear movement of the rear assembly 8 of the device 4 corresponds to the rotation of the shaft 6 in the direction of arrow F2 in Figure 14, bringing the cams 19 on a new axis X2, traveling through an angle a2 greater than a1. The described rotation of the shaft 6 corresponds to the linear sliding of pawls 22 of the blade holder cover 11 in their linear seats 20, resulting in the blades 7 moving closer to each other until reaching a mutual distance D2, smaller than the previous distance D1 (Figure 18).

[0053] Continuing in its linear movement, the controlled electronic axis 23 brings the assembly of dowels 17 and balls 16 to the position L3 in Figure 15, with the balls 16 sliding within the groove 15 of the stem 14 of the shaft 6.

[0054] This linear movement of the rear assembly 8 of the device 4 corresponds to the rotation of the shaft 6 in the direction of arrow F3 in Figure 15, bringing the cams 19 on a new axis X3, traveling through an angle a3 greater than a2. The described rotation of the shaft 6 corresponds to the linear sliding of the pawls 22 of the blade holder cover 11 in their linear seats 20, resulting in the overlapping of the cutting edges of the blades 7 over a stretch D3 of their length (Figure 19).

[0055] When using the stripping device 4 of the invention, the end of the cable 1 to be stripped is inserted between the blades 7, passing through the hole 26 of the blade holder cover 11 , in the blade initial resting position illustrated in Figure 16. The presence of this end is detected by a photocell (not shown), which causes the rotation of the motor 7 and the complex of front assembly 5, rear assembly 8, and shaft 6 to start.

[0056] An electronic unit 27 executes the command related to the controlled movement of the electronic axis 23, which causes the linear sliding of the rear assembly 8. In this way, the corresponding rotation of the disc-shaped body 18 of the shaft 6 is achieved by the sliding of balls 16 within the groove 15 of the stem 14 of the shaft 6. The described rotation of the shaft 6, in turn, causes the sliding of the pawls 22 of the blades 7 against their respective cams 19, resulting in the gradual approach of the blades 7, as described previously, allowing the cable 1 to be stripped according to the levels D1 and D2 shown in Figure 1 , corresponding to the blade positions illustrated in Figures 17 and 18, respectively.

[0057] Continuing in their mutual approach movement, caused by the analogous rotation of the disc-shaped body 18 of the shaft 6, the blades 7 completely close the access hole 26 for the cable 1 , overlapping by a stretch D3 of their length, corresponding to the cutting operation of the cable 1 (Figure 19).

[0058] Moreover, by adjusting the rotation periods of the motor 9 and the path length of the balls 16 within the groove 15 of the shaft 6, the electronic unit 27 allows the selection of the degree of stripping level for the cable 1 , depending on the thickness and number of external coatings on its metal part. The same electronic unit 27 finally controls the return movement of the electronic axis to the initial position LO of the rear assembly 8, completing the stripping operation of the cable 1 .

[0059] In this way, thanks to the invention, the two blades 7 perform both the stripping operation of the cable 1 , i.e., the more or less partial removal of its external insulating coating, and its final cutting.

[0060] Modifications can be made to the invention, as described and illustrated in the figures of the attached drawings, to create variations that however fall within the scope of the invention. Thus, the electronic axis 23 could be replaced by other motor means in general, such as of electric or hydraulic type, and similar. Additionally, the stripping operation of the cable 1 could be programmed to selectively strip any possible additional insulating layers beyond those shown in Figure 1 .

Claims

CLAIMS1. Rotary stripping device for electric cables in general, particularly for coaxial cables, characterized in that it comprises a front assembly (5) equipped with a cover (11 ) frontally closing and slidingly housing two blades (7) for stripping and cutting said cable (1 ), a shaft (6) integral with a disc-shaped body (18) for moving said blades (7) and a rear assembly (8), a motor (9) and belt (10) system being provided to rotate the aforementioned complex of the front assembly (5) with cover (11 ), rear assembly (8), and shaft (6), in which said rear assembly (8) causes said shaft (6) to rotate relative to the front blade holder assembly (5), so as to vary the relative distance between the stripping blades (7) of the cable (1 ), said blades (7) being provided with supports (21 ) and pawls (22) for their movement by engagement with corresponding cams (19) provided on said disc-shaped body (18), said shaft (6) having a stem (14) equipped with a helical groove (15), made on the outer surface of the stem (14) itself, wherein said rear assembly (8) includes at least one system of balls (16) and dowels (17) for the sliding housing of said balls within said helical groove (15) of the stem (14) of the shaft (6).

2. The device according to claim 1 , characterized in that said cover (11 ) has a linear seat (20) for the sliding of said supports (21 ) of said blades (7), said pawls (22) being fixed protruding on the supports (21 ) themselves.

3. The device according to claim 2, characterized in that said disc-shaped body (18) has a hollow seat (18a), on the inner edge of which said cams (19) are provided for engagement with the corresponding pawls (22) of said blades (7).

4. The device according to claim 3, characterized in that the sliding of said pawls (22) against the respective cams (19) of the disc-shaped body (18) causes the blades (7), which are mutually aligned and have opposing ends, to move apart and come closer together, thus adopting a jaw-like relative movement.

5. The device according to claim 4, characterized in that said stripping device (4) is also provided with motor means (23) for the linear movement of said rear assembly (8) on said shaft (6) relative to the front blade holder assembly (5), during said linear movement of the rear assembly (8) said system of balls (16)and dowels (17) being slidingly engaged in said disc-shaped groove (15) of the stem (14) of the shaft (6).

6. The device according to any of the preceding claims, characterized in that said rear assembly (8) is provided with a linear guide (24) for sliding on said shaft (6) and with pins (12), in which said pins (12) are slidably housed within corresponding seats (13) of said front assembly (5) to achieve the transfer, to the rear assembly (8) itself, of the rotational motion imparted by the motor (9) and the corresponding belt (10) to the front assembly (5) itself.

7. The device according to any of the preceding claims, characterized in that said cover (11 ) is fixed to said front assembly (5) by means of screws (25).

8. The device according to any of the preceding claims, characterized in that said blade holder cover (11 ) has an insertion hole (26), between said blades (7), for the end of the cable (1 ) to be stripped.

9. The device according to one or more of the preceding claims, characterized in that it further comprises an electronic control (27) for the movements of said motor means (23).

Images