EP4691749A1

EP4691749A1 - Hexagonal crimping device with crankshaft

Info

Publication number: EP4691749A1
Application number: EP24193214.4A
Authority: EP
Inventors: MATOS Sandra; Jorge Humberto GUERRA; Carlos Miguel Silva PIRES; Rui Miguel Baptista DIAS; Filipe Andre Antao Ferreira SILVESTRE
Original assignee: Aptiv Technologies AG
Current assignee: Aptiv Technologies AG
Priority date: 2024-08-06
Filing date: 2024-08-06
Publication date: 2026-02-11

Abstract

Hexagonal crimping device, comprising two pressure blocks (1, 2), each pressure block (1, 2) comprising sliding jaws (14) adapted to crimp a hexagonal shape when the pressure blocks (1, 2) are in a close position, and comprising :- linear guides for the pressure blocks;- a crankshaft (9) adapted to be driven in continuous rotation;- a first connecting rod (11) pivotally connected at one end to a crankpin (10) of the crankshaft (9), and having a pivot (12) at the other end;- a second connecting rod (13), one end of which is connected to said pivot (12), and the other end of which is attached to one of the pressure blocks (1, 2).

Description

TECHNICAL DOMAIN

The invention concerns the field of production means relating to electrical connectors, and in particular means enabling the mass production of wiring elements requiring a crimping step of a terminal onto the end of a conductor such as a cable.
The crimping of a terminal onto the end of a conductor is one of the most reliable and widely used means of electrical connection in all industries, particularly in industries where crimping operations are used in high-volume, high-speed production, such as the automotive industry.
In particular, the crimping of large lugs for large cross-section cables, used in particular for electric vehicles, presents special requirements.

PRIOR ART

Crimping tools commonly used in the industry generally comprise two pressure blocks movable relative to each other in a clamping direction, each pressure block comprising sliding jaws adapted to crimp a hexagonal shape when the pressure blocks are in a close position.
These methods generally require presses equipped with servomotors and precise control systems, making them expensive and not sufficiently robust for some heavy duty industries.

DISCLOSURE OF THE INVENTION

The purpose of the invention is to improve the crimping devices of the prior art.
To this end, the invention relates to a hexagonal crimping device for crimping electrical lugs on cable terminals, comprising two pressure blocks movable relative to one another in a clamping direction, each pressure block comprising sliding jaws adapted to crimp a hexagonal shape when the pressure blocks are in a close position. This crimping device comprises :

linear guides for the pressure blocks in the clamping direction;
a crankshaft adapted to be driven in continuous rotation by a motor about an axis of rotation substantially perpendicular to the clamping direction, this crankshaft comprising a crankpin;
a first connecting rod pivotally connected at one end to the crankpin of the crankshaft, and having a pivot at the other end;
a second connecting rod, one end of which is connected to said pivot, and the other end of which is attached to one of the pressure blocks.

Furthermore, the first connecting rod being aligned with the second connecting rod in: an opening configuration in which the crankpin of the crankshaft is at top dead center; and a crimping configuration in which the crankpin of the crankshaft is at bottom dead center.
According to another object, the invention relates to a method for hexagonal crimping of electrical terminals on cable terminals, using a hexagonal crimping device as described above, in which the crankshaft is driven in continuous rotation by a motor about an axis of rotation substantially perpendicular to the clamping direction.
The crimping device and process according to the invention are robust and inexpensive, requiring few control systems, and no complex components such as servo-controlled cylinders, computing electronics, etc. However, this crimping device can be used in high standards industries, with high production rates.
Despite the low cost involved, the invention produces crimping operations of high quality and guaranteed reliability, which is mandatory for the automotive industry, and in particular for the production of electric vehicles.
The crimping device according to the invention may comprise the following additional features, alone or in combination:

the crankshaft is driven in rotation always in the same direction;
the linear guides for the pressure blocks comprise: at least one rod parallel to the clamping direction and integral with one of the pressure blocks; and at least one corresponding slot integral with the other pressure block;
the linear guides of the pressure blocks comprise at least one slide element mounted on the two pressure blocks;
said slide element mounted on the two pressure blocks comprises a rod integral with one of the pressure blocks, and a complementary slot integral with the other pressure block;
the pressure blocks each comprise two lateral flanges in which the sliding jaws are mounted, said complementary slot integral with the other pressure block being fixed to the edge of the two lateral flanges of the corresponding pressure block;
it comprises two bases, each pressure block being mounted on one of these bases, the second connecting rod being fixed to the base carrying the corresponding pressure block;
the linear guides of the pressure blocks comprise at least one slide element mounted on the two base;
each pressure block comprises a fixed jaw and two sliding jaws movable in intersecting grooves.

PRESENTATION OF FIGURES

Further features and advantages of the invention will be apparent from the following non-limiting description of examples of illustrative embodiments, with reference to the appended drawings in which :

Figure 1 is a perspective view of a crimping device according to the invention;
Figure 2 is a front view of the crimping device;
Figures 3 to 6 are kinematic diagrams of the crimping device;
Figure 7 is a detail view of the two pressure blocks of the crimping device;
Figure 8 is a view of the inside of the pressure blocks;
figure 9 is a view of the jaw arrangement in the pressure blocks.

Elements which are similar and common to the various embodiments bear the same figure reference numbers

DETAILED DESCRIPTION

Figure 1 is a perspective view of a crimping device according to the invention. This crimping device enables hexagonal crimping of electrical terminals onto cable ends. Sequentially, the end of a cable is thus presented to the crimping device with a terminal to be crimped in place, and crimping operation is carried out sequentially at a rate suited to the desired series production.
The crimping device comprises two pressure blocks 1, 2 which are movable relative to one another in a clamping direction. In the present example, the clamping direction is vertical and the crimping device therefore comprises an upper pressure block 1 and a lower pressure block 2.
These pressure blocks 1, 2 are shown in a spread position in Fig. 1 and are adapted to assume a close-together position in which they are arranged at a predetermined distance from one another, corresponding to the form to be crimped.
The crimping device also includes means for linearly guiding the pressure blocks in the clamping direction.
In the present example, these linear guiding means comprise rods 3 extending in the clamping direction and slots 4 consisting of bores cooperating with the rods 3 by means of a sliding fit between these rods and slots.
In the present example, the crimping device comprises a first base 5 to which the upper pressure block 1 is attached, and a second base 6 to which the lower pressure block 2 is attached. Rods 3 and slots 4 are arranged respectively on one and the other of these bases 5, 6.
The means of linear guidance of the pressure blocks in the clamping direction in this example also comprise guide means attached directly to the pressure blocks 1, 2. In the present example, these guide means comprise a rectangular-section rod 7 and a complementary slot 8. The rectangular-section rod 7 is located on the lower pressure block 2, and the slot 8 is attached to the upper pressure block 1 (see figure 8).
Precise linear guidance of the movement of the pressure blocks 1, 2 in the clamping direction, as they are brought together for crimping, is thus achieved with a first reference on the bases 5, 6 on the one hand (thanks to the rods 3 and slots 4) and with a second reference on the pressure blocks 1, 2 themselves on the other hand (thanks to the rod 7 and slot 8).
The crimping device is adapted to motorize the movement of the pressure blocks 1, 2 by means of :

a crankshaft 9 which is driven in continuous rotation by a motor (e.g. an electric or hydraulic motor) about an axis of rotation substantially perpendicular to the clamping direction. This crankshaft 9 comprises a crankpin 10 which is therefore adapted to occupy, along the clamping direction, a top dead center (the one illustrated in Figure 1) and a bottom dead center;
a first connecting rod 11, connected at one end to the crankpin 10 of crankshaft 9, with a pivot 12 at the other end;
a second connecting rod 13, connected at one end to the pivot 12 and at the other end to the pressure block 1.

The first connecting rod 11 and the second connecting rod 13 are arranged so as to be aligned when the crimping device is in an opening configuration and when the crimping device is in a crimping configuration. In the opening configuration, the crankpin 10 is at top dead center, and in the crimping configuration, the crankpin 10 is at bottom dead center.
Figure 2 shows a front view of the crimping device in its open configuration. In this configuration, the pressure blocks 1, 2 are spread as far apart as possible, allowing the elements to be crimped (not shown) to be inserted.
Figures 3 to 6 are schematic diagrams illustrating the cyclic movement of the crimping device, which alternates between its opening configuration and its crimping configuration. In particular, these figures show the movement of the first connecting rod 11 and the second connecting rod 13.
Figure 3 illustrates the kinematics of the crimping device when it is in the open configuration (as in Figure 2). The crankpin 10 is then at its top dead center, which is its point of maximum vertical height, in this example where the clamping direction is vertical. In other words, at its top dead center, pin 10 is at its point of maximum distance from the lower pressure block 2.
From this opening configuration in Figure 3, the motor driving crankshaft 9 is activated, and crankshaft 9 rotates according to the arrow shown in the figures.
Figure 4 illustrates an intermediate position between the opening configuration and the crimping configuration. In this intermediate position, the crankpin 10 has turned a quarter-turn to the right (in the example shown in Figure 4). The first connecting rod 11 is then positioned obliquely, causing the pivot 12 to move downwards, which in turn causes the second connecting rod 13, and the upper pressure block 1, to move downwards.
Figure 5 illustrates the next stage in which the crimping device has reached its crimping configuration. The crankpin 10 is now at its bottom dead center, which is its point of minimum vertical height, in this example where the clamping direction is vertical. In other words, at its bottom dead center, pin 10 is at its point of maximum approach to the lower pressure block 2.
Note that the notion of top dead center and bottom dead center (for the position of the crankpin 10) designates a position relative to the lower pressure block 2, linked to crankshaft rotation, whatever the arrangement of the clamping direction. The clamping direction may, for example, be horizontal, in which case top dead center of crankpin 10 is always a position corresponding to the pressure blocks 1, 2 moving apart, and bottom dead center of crankpin 10 is always a position corresponding to the pressure blocks 1, 2 moving towards each other.
In the crimping configuration shown in Figure 3, the pressure blocks 1, 2 are brought together along the clamping direction.
Figure 6 illustrates the next step, with further rotation of the crankshaft 9. The crimping device is now in an intermediate position between the crimping configuration and the return to the opening configuration.
From the position shown in Figure 6, further rotation of the crankshaft 9 returns the crimping device to the open configuration shown in Figure 3, and the cycle continues with the removal of crimped elements, the insertion of new crimping elements, and a new cycle of crimping operation.
Switching from the opening configuration to the crimping configuration, and vice versa, is achieved solely by crankshaft rotation, without any special control means, and can be carried out continuously.
For the actual crimping operation, the pressure blocks 1, 2 also each have 3 jaws 14.
The jaws 14 are adapted to close a hexagonal crimping shape when the pressure blocks 1, 2 are in the crimping configuration.
Figures 7 to 9 illustrate an example of the arrangement of these jaws 14, enabling hexagonal crimping and compatible with the movement of crankshaft 9.
Figure 7 shows the pressure blocks 1, 2 being brought together. In this example, each pressure block 1, 2 has three jaws: a fixed jaw 14A, and two movable jaws 14B, 14C.
Jaws 14A, 14B, 14C are adapted to clamp together to define the hexagonal shape 15 shown in figure 7.
Figure 8 is a partial cross-section perspective view showing how the jaws 14A, 14B, 14C operate In this example, the movable jaws 14B, 14C are mounted in grooves 17 forming guides, between two lateral flanges 16 (only one of these lateral flanges 16 has been shown in figure 8 to make the assembly visible).
Grooves 17 are formed on each lateral flange 16.
The movable jaws 14B, 14C also feature a housing 18 for a spring (not shown) adapted to push the jaws 14B, 14C towards their maximum extended position.
The two pressure blocks 1, 2 feature the same jaws 14A, 14B, 14C, but distributed in rotationally symmetrical fashion.
Figure 9 is a schematic front view showing the arrangement of jaws 14A, 14B, 14C, and slides 17 in transparency. The slides 17 run concurrently.
The pressure blocks 1, 2 are thus adapted, by their approach, to bring the jaws 14C of one pressure block into contact with the fixed jaws 14A of the other, opposite pressure block. Further movement towards each other causes the jaws 14C to slide over the jaws 14A, with the movable jaws 14B and 14C retracting, and the six surfaces thus defined moving towards each other until crimping takes place.
Alternative designs are also possible. In particular, the dimensions of crankshaft 9, connecting rods 11, 13 and jaws 14A, 14B, 14C will be adapted to a particular desired crimping dimension.

Claims

Hexagonal crimping device for crimping electrical lugs on cable terminals, comprising two pressure blocks (1, 2) movable relative to one another in a clamping direction, each pressure block (1, 2) comprising sliding jaws (14B, 14C) adapted to crimp a hexagonal shape when the pressure blocks (1, 2) are in a close position, this crimping device being characterized in that it comprises :
- linear guides for the pressure blocks in the clamping direction;

- a crankshaft (9) adapted to be driven in continuous rotation by a motor about an axis of rotation substantially perpendicular to the clamping direction, this crankshaft (9) comprising a crankpin (10);

- a first connecting rod (11) pivotally connected at one end to the crankpin (10) of the crankshaft (9), and having a pivot (12) at the other end;

- a second connecting rod (13), one end of which is connected to said pivot (12), and the other end of which is attached to one of the pressure blocks (1, 2);
the first connecting rod (11) being aligned with the second connecting rod (13) in: an opening configuration in which the crankpin (10) of the crankshaft (9) is at top dead center; and a crimping configuration in which the crankpin (10) of the crankshaft (9) is at bottom dead center.
Hexagonal crimping device according to claim 1, characterized in that the crankshaft (9) is driven in rotation always in the same direction.
Hexagonal crimping device according to one of the preceding claims, characterized in that the linear guides for the pressure blocks comprise: at least one rod (3, 7) parallel to the clamping direction and integral with one of the pressure blocks; and at least one corresponding slot (4, 8) integral with the other pressure block.
Hexagonal crimping device according to one of the preceding claims, characterized in that the linear guides of the pressure blocks comprise at least one slide element (7, 8) mounted on the two pressure blocks (1, 2).
Hexagonal crimping device as claimed in claim 4, characterized in that said slide element mounted on the two pressure blocks comprises a rod (7) integral with one of the pressure blocks, and a complementary slot (8) integral with the other pressure block.
Hexagonal crimping device according to one of the preceding claims, characterized in that the pressure blocks (1, 2) each comprise two lateral flanges (16) in which the sliding jaws (14B, 14C) are mounted, said complementary slot (8) integral with the other pressure block being fixed to the edge of the two lateral flanges (16) of the corresponding pressure block.
Hexagonal crimping device according to one of the preceding claims, characterized in that it comprises two bases (5, 6), each pressure block (1, 2) being mounted on one of these bases (5, 6), the second connecting rod (13) being fixed to the base carrying the corresponding pressure block.
Hexagonal crimping device as claimed in claim 7, characterized in that the linear guides of the pressure blocks comprise at least one slide element (3, 4) mounted on the two base (5, 6).
Hexagonal crimping device according to one of the preceding claims, characterized in that each pressure block (1, 2) comprises a fixed jaw (14A) and two sliding jaws (14B, 14C) movable in intersecting grooves (17).
Method for hexagonal crimping of electrical terminals on cable terminals, using a hexagonal crimping device according to one of claims 1 to 9, characterized in that the crankshaft (9) is driven in continuous rotation by a motor about an axis of rotation substantially perpendicular to the clamping direction.