Quick-locking power cable terminal block

Abstract

The invention relates to a terminal block (1) for connecting a power cable to an electrical conductor (1e), the terminal block (1) comprising: - a casing (1a); - an actuating lever (3) pivotably connected (3e) to the casing (1a) between a position referred to as the release position and a position referred to as the clamped position of the end portion of the power cable; - a fixed jaw (1c) integrated into the casing (1a) and connected to the electrical conductor (1e); - a movable jaw (2) having a clamping face (2c) that cooperates with the fixed jaw (1c) in order to clamp the end of a power cable when the actuating lever (3) is in the clamped position; - at least one groove (1h) for guiding the movable jaw (2) in translation perpendicular to the fixed jaw (1c); and - an intermediate connecting rod (4) for converting the rotation of the actuating lever (3) into translation of the movable jaw (2).

Description

[0001] DESCRIPTION

[0002] QUICK-LOCK POWER CABLE TERMINAL BLOCK

[0003] TECHNICAL FIELD

[0004] The invention relates to a power cable terminal block for connecting and supplying power to equipment with a high current, generally exceeding several tens of amperes. Electrical cables capable of carrying such current are called power cables. More specifically, the present invention relates to the connection of electrical equipment in an aircraft.

[0005] In aircraft, all the electrical power consumed is produced by the engines, which generate a high-intensity current. Furthermore, most of the aircraft's electrical equipment is installed in cabinets that are directly powered by the engines, with the equipment being electrically connected to the cabinets via power cables. Electrical connection interfaces, and in particular multi-connection terminal blocks, are therefore used to connect and supply power to the electrical equipment.

[0006] In general, electrical connection and power supply interfaces are used in any vehicle and industrial-type building in which high-intensity electrical currents flow.

[0007] STATE OF THE ART

[0008] Generally, power cables are connected to electrical cabinets using a suitable screw-nut assembly. The end of the power cable is fitted with a lug, which is held against a conductive plate on the electrical cabinet by tightening the screw-nut assembly. However, such a connection has several drawbacks. First, tightening the screw-nut assembly causes local deformation and uneven contact pressure between the lug and the conductive plate. This impairs the flow of high-intensity electrical current due to a restricted surface area, increasing electrical contact resistance. These drawbacks, in particular, produce localized heating of the connection, leading to power losses and a risk of fire.To compensate for these losses, more power is produced, which means that an aircraft needs more powerful, heavier, and more kerosene-consuming generators and therefore engines.

[0009] Furthermore, tightening each cable connection with a screw and nut has the added disadvantage of being a time-consuming operation during aircraft assembly, as this assembly can involve connecting dozens of cables to screw terminals. During each screw and nut tightening, the torque is calibrated and then checked for each screw. Indeed, improper tightening can subsequently lead to a loss of the electrical connection. This operation also carries the risk of losing a screw or nut within the aircraft structure, the retrieval of which would delay the aircraft assembly.

[0010] On the other hand, this connection solution requires a large number of screw and nut part numbers to adapt the screw-nut assemblies to each power cable. This large number of part numbers leads to more complex inventory management and increases the risk of errors when assembling the screws and nuts during power cable connections. Since the nuts are replaced during maintenance of the power cable connections, the large number of nut part numbers also creates a risk of assembly errors during maintenance.

[0011] For domestic applications where electrical currents are low, terminal blocks are commonly used to connect electrical cables. However, the cables are secured with screws in terminal blocks, which present the same drawbacks of uneven contact and time-consuming installation. Lever terminal blocks facilitate cable connection by simply operating a lever, without the need for any additional tightening tools. These terminal blocks are quick to install and allow for screwless and nutless connection of electrical cables. In the lever terminal block described in patent application DE 10237701, operating the lever deforms a flexible blade, allowing the electrical cable to be inserted into the terminal block. Closing the lever releases the flexible blade, which returns to its original position, pinching the electrical cable against a busbar, thus completing the connection in the terminal block.

[0012] However, a domestic lever terminal block is designed to connect cables carrying low currents. Such a domestic lever terminal block therefore has the disadvantage of not being suitable for high currents, which lead to deformation of the flexible blade and consequently a loss of cable clamping. This deformation results from the heat generated by the high current. Furthermore, since the lever terminal block is installed in a fixed structure, the flexible blade and lever are not suitable for environments subject to strong vibrations, such as in an aircraft. Vibrations can cause the lever or flexible blade to move, leading to a loss of electrical conductivity due to contact corrosion, or even, in extreme cases, the electrical cable to come loose.

[0013] DESCRIPTION OF THE INVENTION

[0014] In order to remedy the disadvantages of the prior art described above, the main objective of the invention is to enable a simplified and rapid interconnection of electrical furniture to the power wiring of an aircraft.

[0015] To achieve this, the invention provides for the creation of a cable terminal block enabling the connection of a power cable to an electrical piece of furniture by means of a quick lever interface adapted to generate homogeneous pressure, without tools or additional fastening elements.

[0016] More specifically, the present invention relates to a terminal block for connecting a power cable to an electrical conductor of an aircraft electrical cabinet, the terminal block comprising:

[0017] - a housing with an opening for inserting a portion of the end of the power cable; - an actuating lever in pivot connection with the housing between a so-called release position and a so-called clamped position of the portion of the end of the power cable; - a fixed jaw integrated into the housing and having an electrical conductor as well as a support and positioning face for the portion of the end of the power cable; - a movable jaw having a clamping face cooperating with the support face of the fixed jaw to clamp the portion of the end of the power cable when the actuating lever is in the clamped position;

[0018] - at least one guide groove integrated into the housing, designed to guide the moving jaw in translation perpendicular to the bearing face of the fixed jaw, and

[0019] - an intermediate connecting rod for converting the rotation of the actuating lever into translation of the moving jaw.

[0020] Advantageously, the terminal block allows for quick and reversible connection of the power cable by moving the operating lever between its open and closed positions without requiring any additional tools. This ensures uniform contact pressure by converting the rotational movement of the operating lever into a translational movement of the movable jaw perpendicular to the fixed jaw. Furthermore, the position of the operating lever allows for immediate visual verification of the power cable's locking status, as it is not locked when the operating lever is not in the closed position.

[0021] Advantageously, by standardizing the contact pressure, the movement of the movable jaw in translation perpendicular to the fixed jaw allows for homogenization of the flow of electric current between the power cable and the connector.

[0022] Advantageously, the intermediate connecting rod also allows for a permanent connection between the actuating lever and the moving jaw, as well as a conversion of the actuating lever's rotational movement into the moving jaw's translational movement. This permanent connection then ensures constant support of the power cable between the fixed and moving jaws as long as the actuating lever remains in the closed position, regardless of environmental vibration conditions. According to preferred embodiments, used alone or in combination: - the fixed jaw is electrically conductive;

[0023] - the movable jaw is insulating;

[0024] - the electrical conductor passes through the fixed jaw;

[0025] - the movable jaw has at least one pad, each pad sliding in a guide groove of the housing:

[0026] - the movable jaw includes a rigid washer forming the clamping face;

[0027] - the movable jaw includes a means for compressing the clamping face; - the means for compressing the clamping face is a set of calibrated spring washers;

[0028] - the movable jaw includes a stop for the actuating lever in the closed position;

[0029] - the terminal block includes a locking mechanism to hold the actuating lever in the closed position;

[0030] - the actuating lever has a hook bar cooperating with the movable dead retaining lock to secure the actuating lever in the closed position; - the terminal block has a seal to verify the locking of the retaining lock; - the housing has a protective and identification cover;

[0031] - the actuating lever includes an assist interface for inserting an actuation aid, and

[0032] - the fixed jaw includes an interface for installing the power cable.

[0033] Advantageously, the stop of the actuating lever in combination with the compression return means makes it possible to stabilize and therefore maintain the actuating lever in its closed position.

[0034] Advantageously, the retaining lock and the verification seal also provide additional visual safeguards, making it possible to ensure on the one hand that the actuating lever is in the tightened position and on the other hand that the actuating lever has not been loosened and then tightened.

[0035] The invention also relates to an aircraft electrical cabinet equipped with at least one row of power cable terminal blocks to supply equipment installed in the electrical cabinet. PRESENTATION OF FIGURES

[0036] Other features and advantages of the present invention will become apparent from the following detailed embodiment, without limiting its scope, by reference to the accompanying figures which represent, respectively:

[0037] - Figure 1, a perspective view of an example of a power cable terminal block according to the present invention;

[0038] - Figure 2, an exploded view of the terminal block in Figure 1;

[0039] - Figure 3, an exploded perspective view of the movable jaw of the terminal block in Figure 1;

[0040] - Figure 4, a perspective view of the terminal block in Figure 1 with the actuation lever locked;

[0041] - Figure 5, a perspective view of the terminal block in Figure 1 with a lug between the fixed jaw and the moving jaw;

[0042] - Figure 6, a perspective view of the terminal block in Figure 5 with the actuation lever locked;

[0043] - Figure 7, a perspective view of a terminal block according to the invention with a protective and identification cover;

[0044] - Figure 8, a simplified cross-sectional view of the terminal block in Figure 1 with the actuation lever in the open position;

[0045] - Figure 9, a simplified cross-sectional view of the terminal block in Figure 1 with the actuation lever in an unstable equilibrium position;

[0046] - Figure 10, a simplified cross-sectional view of the terminal block in Figure 1 with the actuation lever in the tightened position;

[0047] - Figure 11, a cross-sectional view of the terminal block of Figure 1 with the actuation lever in the tightened and locked position;

[0048] - Figure 12, a perspective view of an example of a terminal block equipped with a verification seal, and - Figure 13, a perspective view of an example of a terminal block equipped with a movable tab to assist the actuation lever.

[0049] DETAILED DESCRIPTION

[0050] In the figures, identical reference symbols refer to the same element as well as to the corresponding passages in the description.

[0051] Figure 1 illustrates a perspective view of an example of a power cable terminal block 1 according to the invention. Such terminal blocks are installed on aircraft electrical racks to supply electrical current to the equipment located within these racks. Since the power supply current is generated by the aircraft engines, its intensity is high (from a few tens to several hundred amperes). Power cables are specifically designed to carry this high-intensity current. These power cables are used to carry the current to each electrical rack, connecting via the terminal block to electrical conductors installed on the aircraft electrical rack to supply power to the equipment.

[0052] In the example, terminal block 1 has a fixed jaw 1c and a movable jaw 2 which, by gripping the power cable (not shown) with uniform pressure, as will be explained in detail later, improve the electrical connection between the power cable and the aircraft's electrical cabinet (not shown). In the configuration illustrated in Figure 1, an actuating lever 3 is in its open position, in which the fixed jaw 1c and the movable jaw 2 are separated to allow the insertion of a power cable.

[0053] Figure 2 shows an exploded view of terminal block 1 which includes:

[0054] - a box 1a having an opening 1b for the insertion of a portion of the end of a power cable (not shown);

[0055] - an actuating lever 3 in pivot connection 3e with the housing 1a between a release position and a clamped position of the end portion of the power cable; - a fixed jaw 1c integrated into the housing 1a and presenting the electrical conductor 1e of a piece of equipment as well as a support face 1d and positioning of the end portion of the power cable; - a movable jaw 2 having a clamping face 2c cooperating with the support face 1d of the fixed jaw 1c to clamp the end portion of the power cable according to a pressure made homogeneous when the actuating lever 3 is in the clamped position;

[0056] - two guide grooves 1h integrated into the housing 1a and intended to guide the movable jaw 2 in translation perpendicular to the bearing face 1d of the fixed jaw 1c, and - an intermediate connecting rod 4 for converting the rotation of the actuation lever 3 into translation of the movable jaw 2.

[0057] The power cable (not shown) in this example has a terminal 6 at its end (see Figure 6). The terminal 6 is in the form of a sleeve 6a that clamps the end of the cable and extends into an eyelet 6b. The eyelet 6b of the terminal is inserted between the bearing surface 1d of the fixed jaw 1c and the moving jaw 2 when the operating lever 3 is in the closed position. Since the fixed jaw 1c is conductive and the moving jaw 2 is insulating, the electric current flows from the terminal 6 to the fixed jaw 1c and then to the electrical conductor 1e connected to the cabinet. The fixed jaw 1c also has on the bearing face 1d an interface for installing the power cable, here a centering 1f for the eyelet 6b of the lug 6. Advantageously, the bearing surface of the movable jaw 2 is greater than the surface of the eyelet 6b, thus allowing the clamping pressure on the lug 6 to be uniform.

[0058] The movable jaw 2 comprises:

[0059] - two pads 2d which cooperate and slide in the guide grooves 1h of the box 1a during the linear translation of the movable jaw 2 in the box 1a;

[0060] - a rigid washer 2b forming the clamping face 2c, and

[0061] - a set of spring washers 2a which constitutes a means of compressive return of the clamping face.

[0062] These spring washers 2a, four in number in this example, are calibrated to provide sufficient force, but less than the plastic deformation threshold of the electrical conductor 1e. This force is distributed across the surface of the rigid washer 2b on the power cable lug when the actuating lever 3 is in the closed position, thus improving the electrical connection between the power supply cable and the aircraft's electrical cabinet. The rigid washer 2b is also sized to frame the cover 1f when the actuating lever 3 is in the closed position and no power cable is present.

[0063] Furthermore, the actuating lever 3 comprises two parallel arms 3c which are assembled to the housing 1a by pivot joints 3e at the rotation end 3a of the actuating lever 3, these pivot joints 3e being located on either side of the opening 1b of the housing 1a. The arms 3c are connected to each other by an actuating base 3d at the drive end 3b of the actuating lever 3, this actuating base 3d being pushed to pivot the actuating lever 3 between its open and closed positions. Alternatively, the actuating lever 3 may comprise only a single central arm 3c.

[0064] In one embodiment, the actuating lever 3 also includes a hook bar 3f disposed on the actuating base 3d, this hook bar 3f being able to be hooked and thus hold the actuating lever 3 in a desired position as described below.

[0065] As for the movable jaw 2 and the actuating lever 3, they are connected by the intermediate connecting rod 4 which converts the rotational displacement of the actuating lever 3 into a translational displacement of the movable jaw 2. This intermediate connecting rod 4 is therefore in rotation at each of its two ends relative to the movable jaw 2 and the actuating lever 3 respectively. In this embodiment, the intermediate connecting rod 4 is composed of two connecting rods 4a linked by a connecting axis 4b and each pivoting relative to a branch 3c of the actuating lever 3.

[0066] The terminal block 1 also includes a retaining latch 5 pivotally positioned on the movable jaw 2. This retaining latch 5 cooperates with the actuating lever 3 by hooking the catch bar 3f of the actuating lever 3 to retain and hold the actuating lever 3 in its closed position. Alternatively, any means of retaining or locking the actuating lever 3 may be implemented; this means may retain or lock the actuating lever relative to the movable jaw 2 or relative to the housing 1a of the terminal block 1.

[0067] The housing 1a has, on either side of the opening 1b, a recess 1i for the installation of a cover 1j (see figure 7) for the protection and identification of the terminal block 1. This cover 1j provides a mechanical and electrical protection shield for the power cable clamped between the fixed jaw 1c and the movable jaw 2. The cover 1j can also include an identification label for the terminal block 1, "PHASE 1" in the example, to interconnect the power cable to the correct terminal block or to locate an interconnection.

[0068] Figure 3 shows a more detailed exploded perspective view of the movable jaw 2, which comprises the cylindrical body 2e bearing against the fixed jaw 1c, a block 2f connecting to the actuating lever 3, and two sliding pads 2d within the housing 1a. The cylindrical body 2e and the pads 2d are oriented perpendicularly to the bearing face 1d of the fixed jaw 1c, with the pads 2d positioned diametrically opposite each other on the lateral surface 2g of the cylindrical body 2e. This perpendicular movement of the movable jaw 2 relative to the bearing face 1d of the fixed jaw 1c ensures a uniform clamping pressure between the rigid washer 2b of the movable jaw 2 and the fixed jaw 1c, the spring washers 2a compensating for any potential misalignment between the pads 2d and the bearing face 1d of the fixed jaw 1c.

[0069] The rigid washer 2b forms the clamping face 2c of the movable jaw 2 at the end of a cylindrical body 2e. A set of spring washers 2a is positioned between the cylindrical body 2e and the rigid washer 2b to provide a means of compressive return for the movable jaw 2. When the actuating lever 3 moves from its open position to its closed position, the movable jaw 2 is translated towards the fixed jaw 1c. Contact between the clamping face 2c of the movable jaw 2 and the power cable is achieved when the actuating lever 3 is in a position intermediate between its release position and its closed position. Upon reaching its closed position, the actuating lever 3 has thus compressed the movable jaw 2 against the fixed jaw 1c (see Figure 4) or against the eyelet 6b of the power cable (see Figure 5), this compression being absorbed by the spring washers 2a.

[0070] In a preferred embodiment, the spring washers 2a and the rigid washer 2b have a diameter substantially equal to that of the cylindrical body 2e. Indeed, the pads 2d extend beyond the lateral surface 2g of the cylindrical body 2e and have a counterbore 2h which serves both to hold the spring washers 2a against the cylindrical body 2e and to retain the rigid spring washers 2a. Each pad 2d is also bounded by a pair of slots 2i into which the teeth 2k of the tabs 2j of the rigid washer 2b fit. The rigid washer 2b has four tabs 2j, each of which has a clip tooth 2k at its free end. These lugs 2j allow the rigid washer 2b to move closer to the cylindrical body 2e of the movable jaw when the drive lever 3 tilts into the clamped position and to hold the spring washers 2a when the drive lever 3 tilts into the release position.

[0071] Figure 4 shows a perspective view of the terminal block 1 with its actuating lever 3 in the clamped position and with the retaining lock 5 hooking the retaining bar 3f. The terminal block 1 is therefore in the clamped position and the actuating lever 3 is locked by the lock 5. In the configuration without power cable illustrated in Figure 4, the rigid washer 2b is not in direct contact with the fixed jaw 1c (see Figure 11).

[0072] In the perspective view of this figure 5, a lug 6 of a power cable has been inserted into the terminal block 1 of figure 1 and the actuating lever 3 has been moved towards its clamped position until the rigid washer 2b comes into contact with the lug 6. By continuing to move the actuating lever 3 towards its clamped position, the movable jaw 2 is pressed against the lug 6, the spring washers 2a compressing to absorb the movement of the movable jaw 2 and apply the desired clamping force, as illustrated in figure 6 where the actuating lever 3 is locked in its clamped position.

[0073] Figure 7 also shows a terminal block 1 without a power cable. The operating lever 3 is in the closed position and a cover 1j, providing the dual function of protection and identification, is installed on the terminal block with the label "PHASE 1".

[0074] Figures 8 to 11 are cross-sectional views of terminal block 1 which illustrate different stages of the state of terminal block 1 depending on the position of the drive lever 3; the fixed jaw 1c is only shown in Figure 11. Axes R1, R2 and R3 define the axes of rotation of the actuating lever 3 with respect to the housing 1a, of the intermediate connecting rod 4 with respect to the actuating lever 3 and of the intermediate connecting rod 4 with respect to the movable jaw 2, respectively. The axis R4 of rotation of the retaining lock 5 (see Figure 11) with respect to the movable jaw 2 is also shown.

[0075] In Figure 8, the drive lever 3 is in the open position, and the axes R1, R2, and R3 form a triangle. When the drive lever 3 is pushed into the position shown in Figure 9, the axes R1, R2, and R3 are aligned. The spring washers 2a are compressed to their maximum and exert a force on the movable jaw 2. As long as the axes R1, R2, and R3 are aligned, the drive lever 3 is in an unstable equilibrium position under the effect of the spring washers 2a.

[0076] By continuing to push the drive lever 3, it leaves its unstable equilibrium position and the spring washers 2a then push the movable jaw 2 towards the drive lever 3 while maintaining contact between the rigid washer 2b and the fixed jaw 1c or the lug 6. The stop 2I of the movable jaw 2 comes into contact with the hook bar 3f of the drive lever 3, which arrives in its clamped position illustrated in Figure 10. Since the clamped position is offset from the unstable equilibrium position, the drive lever 3 is held in this clamped position against the stop 2I under the force generated by the spring washers 2a. To open the terminal block, sufficient force must be exerted on the drive lever 3 to reach the maximum compression force of the spring washers 2a and the drive lever 3 must be tilted to the other side of the unstable equilibrium position.

[0077] In Figure 11, the retaining lock 5 cooperates with the hook bar 3f to engage and secure the actuating lever 3 in the closed position. This engagement holds the actuating lever 3 even when a force greater than the compressive force of the spring washers 2a is applied to the drive lever 3.

[0078] Figure 12 shows an alternative embodiment of the terminal block 1 which includes a verification seal 7 for locking the latch 5. The verification seal 7 is installed here on adapted loops 7a and 7b on, respectively, the retaining latch 5 and the drive lever 3. This verification seal 7 ensures that the interconnection of the power cable has not been altered and that the actuating lever 3 has not been actuated and then returned to its original position. In another embodiment also shown in Figure 12, the drive lever 3 includes an assist interface, here a bore 3g, allowing the insertion and use of a rigid rod-type actuation aid accessory.

[0079] In yet another variant illustrated in Figure 13, the drive lever 3 has a movable tab 3h on its drive end 3b. These means of assisting the actuating of the drive lever 3 increase the lever arm and therefore require less effort to swing the drive lever 3 between its open and closed positions.

[0080] The invention is not limited to the examples described and illustrated. Any type of return mechanism can be used in place of the spring washers, such as a compression or leaf spring. The return mechanism can also be part of the fixed jaw or positioned between the fixed and moving jaws. Generally, several terminal blocks according to the invention are installed in parallel on the electrical cabinet to power a series of electrical devices.

[0081] Furthermore, the end portion of the power cable can be directly inserted between the moving and fixed jaws or any other type of end suitable for such insertion.

Claims

DEMANDS 1. Terminal block (1) intended for connecting a power cable to an electrical conductor (1 e) of an aircraft electrical cabinet, the terminal block (1 ) comprising: - a housing (1a) having an opening (1b) for inserting a portion of the end of the power cable - an actuation lever (3) in pivot connection (3e) with the casing (1a) between a so-called release position and a so-called tightened position of the end portion of the power cable; - a fixed jaw (1c) integrated into the casing (1a) and presenting the electrical conductor (1e) as well as a support face (1d) and positioning of the end portion of the power cable; - a movable jaw (2) having a clamping face (2c) cooperating with the support face (1d) of the fixed jaw (1c) to clamp the end portion of the power cable when the actuating lever (3) is in the clamped position; the terminal block (1) being characterized in that it includes at least one guide groove (1h) integrated into the housing (1a) intended to guide the movable jaw (2) in translation perpendicular to the bearing face (1d) of the fixed jaw (1c) as well as an intermediate connecting rod (4) for converting the rotation of the actuating lever (3) into translation of the movable jaw (2).

2. Terminal block (1) according to the preceding claim, in which the fixed jaw (1c) is electrically conductive.

3. Terminal block (1) according to any one of claim 1 to claim 2, wherein the movable jaw (2) is insulating.

4. Terminal block (1) according to any one of claim 1 to claim 3, in which the electrical conductor (1e) passes through the fixed jaw (1c).

5. Terminal block (1) according to any one of claim 1 to claim 4, wherein the movable jaw (2) comprises at least one pad (2d), each pad (2d) sliding in a guide groove (1h) of the housing (1a).

6. Terminal block (1) according to any one of claims 1 to claim 5, wherein the movable jaw (2) comprises a rigid washer (2b) forming the clamping face (2c) 7. Terminal block (1) according to any one of claims 1 to claim 6, wherein the movable jaw (2) comprises a means for compressively returning the clamping face (2c).

8. Terminal block (1) according to claim 7, wherein the means for compressing the clamping face (2c) is a set of calibrated spring washers (2a).

9. Terminal block (1) according to any one of claim 1 to claim 8, wherein the movable jaw (2) has a stop (2I) for the actuating lever (3) in the closed position.

10. Terminal block (1) according to any one of claim 1 to claim 9, wherein the terminal block (1) has a retaining lock (5) in the closed position of the actuating lever (3).

11. Terminal block (1) according to claim 10, wherein the actuating lever (3) has a hook bar (3f) cooperating with the retaining lock (5) to secure the actuating lever (3) in the closed position.

12. Terminal block (1) according to any one of claim 10 to claim 11, wherein the terminal block (1) includes a verification seal (7) for locking the retaining lock (5).

13. Terminal block (1) according to any one of claim 1 to claim 12, wherein the housing (1a) includes a protective and identification cover (1j).

14. Terminal block (1) according to any one of claim 1 to claim 13, wherein the actuating lever (3) has an assist interface (3g, 3h) for the insertion of an actuation aid for the actuating lever (3).

15. Terminal block (1) according to any one of claim 1 to claim 14, wherein the fixed jaw (1c) has an installation interface (1f) for the power cable.

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