Energy-saving contact with adjustable end stop

Abstract

The invention relates to an energy-saving contact (1) comprising a fixed part (2) and a mobile part (3) able to move in a main direction (Z) between a contact position and a breaking position, the energy-saving contact (1) comprising a spring blade (8) fixed to the fixed part (2) and forming an electrical contact, as well as an end stop (10) mounted on the mobile part (3) and arranged so as to be distant from the blade (8) and to come to press against the blade (8) when the mobile part (3) is in the contact position. The fixed part (2) defines an orifice (11) through which the end stop (10) passes opposite the blade (8), the orifice (11) having an internal cross section substantially identical to an external cross section of the end stop (10), the end stop (10) being mounted on the mobile part (3) such as to be mobile translationally in a plane (XY).

Description

[0001] DESCRIPTION

[0002] TITLE: Adjustable stop saver contact

[0003] Technical field of the invention

[0004] The invention relates to the field of power electronics switching components.

[0005] More particularly, the invention relates to an economizer contact for aircraft.

[0006] State of the prior art

[0007] A contactor is a switching device for power electronics, comprising a moving part moved by a mechanical actuator to establish and break an electric current.

[0008] To limit the electrical consumption of actuators in contactors, a known solution is to use a so-called economizer contact, activating a so-called holding coil at the end of travel of the moving part of the contactor.

[0009] Such an electric economizer contactor 1 is shown in Figure 1, composed of a fixed part 2 and a movable part 3 which performs a translational movement in the Z direction between a high electric contact position and a low position where the contact is cut.

[0010] The movable part 3 is biased towards its low position by one or more springs (not shown), so that the movable part is in the low position at rest.

[0011] The movable part 3 is driven in translation towards its high position by the action of an actuating coil when an actuating current flows therein, acting by induction on a core mounted on the movable part 3 and engaged between the turns of the actuating coil.

[0012] The translational movement of the movable part 3 makes it possible to establish electrical contact between an auxiliary blade 5 secured to the movable part 3 and an electrical card 6 secured to the fixed part 2.

[0013] The electric economizer contactor 1 further comprises at least one blade 8 mounted on the fixed part 2 carrying a contact pad 9 forming an economizer contact with a fixed contact, and at least one stop 10, mounted on the mobile part 3 and arranged to interact with the blade 8 during the travel of the mobile part 3.

[0014] The economizer contact is closed at rest by the action of the blade 8 which urges the contact pad 9 towards the fixed contact, and opens when the stop 10 comes to bear against the blade 8 in the high position of the moving part 3.

[0015] The stop 10 is for example a pin projecting in the Z direction from the auxiliary blade 5 and passing through an orifice 11 opening in the electrical card 6 opposite the blade 8. The interaction between the blade 8 and the stop 10 makes it possible to open the economizer contact and to switch the operation of the electrical contactor by cutting the current in the actuating coil and keeping the current in a holding coil, which consumes less energy.

[0016] The adjustment of the interaction between the blade 8 and the stop 10 is important in the sense that if the tilting towards the holding coil occurs too early in the travel of the moving part 3, the latter may lack power to reach the end of travel and the economizer contact 1 may reopen under the effect of the return.

[0017] If the interaction between the blade 8 and the stop 10 occurs too late, the separation distance of the economizer contact, between the pad 9 and the fixed contact, may be too short and cases of rebound or even sticking may occur, preventing the economizer from functioning correctly.

[0018] A cover is usually assembled around the assembly formed by the blade and the economizer contact, in order to protect it from the outside.

[0019] Examples of economizer contacts are described in documents CN208352212U, CN89211913U and CN211376540U.

[0020] However, a problem not addressed by known economizer contact systems is the potential presence of dust at the economizer contact, despite the said cover.

[0021] In fact, the passage hole of the stop in the electrical card is much larger than the circumference of said stop, to accept significant positioning tolerances of the economizer contact stop.

[0022] The dimensions required for this hole allow dust to enter the closed space in the cover around the economizer contact, which can make it impossible for current to pass. Thus, when the economizer contact is closed, the current passing through both the inrush and holding coils prevents the economizer contact from closing.

[0023] Presentation of the invention

[0024] The invention aims to overcome these drawbacks. To this end, the subject of the invention is an electric economizer contactor comprising a fixed part and a part movable in translation relative to the fixed part in a main direction, between a contact position of the electric contactor and a cut-off position of the electric contactor, the electric economizer contactor comprising an elastic blade fixed to the fixed part by a first end and a second end of which forms an economizer contact, as well as a stop mounted on the movable part and arranged to be away from the elastic blade when the movable part is in its cut-off position, the economizer contact then being closed, and to come to bear on the elastic blade when the movable part is in the contact position, the economizer contact then being open,characterized in that the fixed part defines an orifice for the passage of the stop opposite the elastic blade in the main direction, the orifice having an internal section transverse to the main direction substantially identical to an external section of the stop, the stop being mounted on the movable part in a movable manner in translation in a plane perpendicular to the main direction.,

[0025] Such an electrical contact prevents pollution of the economizer contact by dust while avoiding the constraints linked to very low manufacturing dimensional tolerances.

[0026] The economizer contact is adapted to switch the actuating current of the contactor to a holding coil when the moving part is at the end of its travel and the economizer contact is closed.

[0027] By substantially identical, we mean that a contour of the section of the orifice follows a contour of the section of the stop with a gap forming a reduced clearance between the stop and the edges of the orifice, the clearance being chosen to be sufficiently small to prevent the passage of dust.

[0028] The clearance is for example less than or equal to 0.5 mm, in particular less than or equal to 0.3 mm.

[0029] The fixed part may comprise an electrical card on which the blade is mounted, by a first end of the blade, and a fixed contact arranged at a second end of the blade, the orifice being defined in the electrical card, opposite the blade.

[0030] Such a feature allows the economizer contact to be kept closed at rest and opened at the end of the travel of the moving part.

[0031] The stop may comprise a foot comprising a flat part mounted to slide between a support and an auxiliary blade of the movable part.

[0032] Such a feature allows to have a stop that can be moved freely in the transverse plane, to easily adjust the position of the stop dynamically.

[0033] The support may comprise a recess receiving the flat portion, the auxiliary blade defining an opening opposite the recess, the stop extending through the opening towards the passage orifice.

[0034] Such a feature allows for robust retention of the stop while providing simple assembly without impacting part arrangements with tight manufacturing tolerances.

[0035] The stop may comprise a threaded rod extending in the main direction and a head mounted on the rod and adjustable in height relative to the rod in the main direction.

[0036] Such a feature allows the height of the stop to be adjusted and thus to modify the point in the travel of the moving part at which the economizer contact opens. The stop may comprise a threaded ring engaged on the threaded rod and carrying the head.

[0037] Such a feature allows for simple and precise adjustment of the head height.

[0038] The ring may have a circular external section having a first radius, the passage orifice having a circular internal section having a second radius, the first radius being less than the second radius by a clearance suitable for preventing the passage of dust.

[0039] Such a feature allows for a good match between the sections of the orifice and the stop, the external surface of the ring being easy to machine precisely. The head may have a bump oriented towards the blade in the main direction.

[0040] Such a feature allows for almost point-to-point contact with the blade.

[0041] The bump can be rounded or pointed.

[0042] The head can be made of insulating material.

[0043] The insulating material is, for example, a polyamide-imide polymer.

[0044] Such a feature helps prevent the formation of stray currents in the stop. The stop may include means for blocking the movement of the head relative to the rod.

[0045] Such a feature allows the head height adjustment to be maintained once it has been made.

[0046] Brief description of the figures

[0047] Figure 1 is a schematic sectional view of a state-of-the-art energy-saving contact, Figure 2 is a partial sectional view of a energy-saving contact according to the invention, Figure 3 is a detailed sectional view of a contact stop of the contact of Figure 2, and Figure 4 is a cross-sectional view of a fixing of the stop of Figure 3.

[0048] Detailed description of the invention

[0049] An electric energy-saving contactor 1 according to the invention is partially shown in Figure 2. The electric contactor comprises a fixed part 2 comprising an electric card 6 and a movable part 3 comprising an auxiliary blade 5, as described previously.

[0050] The movable part 3 is movable in translation in a main direction Z under the action of an actuating coil (not visible in figure 2), so as to bring the electrical card 6 and the auxiliary blade 5 closer together.

[0051] The electrical card 6 and the auxiliary blade 5 extend substantially parallel to each other, perpendicular to the main direction Z. The electrical card 6 comprises a support 7 carrying an elastic blade 8, said blade 8 being fixed to the support 7 by a first end and carrying a contact pad 9 at its free end.

[0052] The contact pad 9 is urged by the blade 8 towards a fixed contact 12 secured to the electrical card 6, so as to form a closed economizer contact at rest.

[0053] An orifice 11 is defined in the electrical card 6 opposite the blade 8 in the main direction Z, the orifice 11 having for example a substantially circular transverse section.

[0054] A stop 10 is coupled to the auxiliary blade 5 and projects from the auxiliary blade 5 in the main direction Z, towards the blade 8.

[0055] The stop 10 is mounted to move relative to the auxiliary blade 5 according to a translational movement in an XY plane perpendicular to the main direction Z.

[0056] The stop 10 is thus able to be positioned opposite the orifice 11 in order to pass through said orifice 11 and to press on the blade 8 during the travel of the movable part 3. The stop 10 comprises four separate parts: a foot 13, a ring 14, a head 15 and a support 16.

[0057] A cover 17 is fixed to the electrical card 6 and surrounds the blade 8, the support 7 and the fixed contact 12, so as to confine them and protect the saving contact from the outside.

[0058] The cover 17 is hermetically fixed on the electrical card 6 to prevent the passage of dust, for example by means of a bolt 18.

[0059] The stop 10 and its attachment to the auxiliary blade 5 are shown in more detail in Figures 3 and 4.

[0060] The foot 13 has a screw shape and comprises a flat portion 21 extending in the XY plane perpendicular to the main direction and a threaded rod 22 projecting from the flat portion 21 in the main direction Z towards the fixed part 2.

[0061] The auxiliary blade 5 defines an opening 23 passing through in the main direction Z, through which the rod 22 passes. The flat portion 21 is located on the side of the auxiliary blade 5 opposite that where the electrical card 6 is located.

[0062] The opening 23 has transverse dimensions, measured in an XY plane perpendicular to the main direction Z, smaller than the transverse dimensions of the flat part 21, so that the flat part 21 has its transverse ends bearing against the auxiliary blade 5 in the main direction Z. In other words, the flat part 21 is wider than the opening 23, transversely to the main direction Z, and therefore cannot pass through the opening 23.

[0063] The support 16 is a plate fixed by crimping under the auxiliary blade 5, bearing in the main direction Z, for example by two fixing members 25 engaged in corresponding fixing orifices 26 of the support 16 and the auxiliary blade 5. Alternatively, the support 16 can be fixed to the auxiliary blade 5 by any other known manner, for example by bolting, screws, welding, etc.

[0064] A non-through recess 27 is provided in an upper face 28 of the support, opposite the auxiliary blade 5. The recess 27 has a depth, measured along the main direction Z, substantially constant over its entire transverse extent and slightly greater than a thickness of the flat portion 21 of the foot 13.

[0065] The flat part 21 is arranged in the recess 27 and held in the main direction Z between the intermediate card 5 and the support 16.

[0066] The depth of the recess 27 is such that a clearance 33 remains between the auxiliary blade 5 and the flat portion 21, so that the flat portion 21 is movable by sliding, in the transverse plane XY between the auxiliary blade 5 and the support 16.

[0067] The sliding clearance 33 is for example less than or equal to 0.5 mm, in particular less than or equal to 0.2 mm.

[0068] Figure 4 shows, in section in the transverse plane XY, the flat portion 21 of the support and the recess. The flat portion 21 and the recess both have elongated shapes in this plane XY in the same transverse direction X, which is for example the direction of alignment of the fixing holes 26 by crimping.

[0069] The flat part 21 is for example substantially rectangular in the transverse plane XY, while the recess has a substantially oblong profile in the XY plane. The flat part 21 has an amplitude of movement 34 in the first transverse direction X and an amplitude of movement 35 in the second transverse direction Y, these amplitudes being sufficient for adjusting the position of the stop 10.

[0070] The ring 14 has the general shape of an annular nut comprising an internal thread engaged on that of the rod 22, making it possible to adjust the height of the ring 14 on said rod 22.

[0071] Changing the height of the ring 14 on the rod 22 makes it possible to adjust the height of the head 15, which is mounted on the ring 14, and thus to modify the moment of opening or closing of the economizer contact in the travel of the movable part 3 relative to the fixed part 2.

[0072] The ring 14 has an external section, transversely to the main direction Z, very close to an internal cross section of the orifice 11 for the passage of the stop 10. Thus, a very small residual clearance between the external wall of the ring 14 and the internal walls of the orifice 11 when the stop 10 passes through the orifice 11 prevents the passage of dust into the escape defined by the cover 17 around the economizer contact.

[0073] The external cross-section of the ring 14 is notably circular.

[0074] The clearance between the external walls of the ring and the internal walls of the orifice is for example less than 0.5 mm, in particular less than 0.3 mm. To compensate for the very small positioning tolerances of the stop 10 due to this very small clearance, an adjustment of the position of the stop 10 opposite the orifice 11 is possible thanks to the translational movement of the latter in the transverse plane XY.

[0075] The head 15 has a generally curved shape and defines a central recess 29 in which the upper end of the rod 22 is engaged, and a top 30 facing the blade 8.

[0076] It allows almost point contact between the stop 10 and the blade 8, which improves the repeatability of the opening and closing of the economizer contact during the movement kinematics of the moving part 3.

[0077] The head 15 also defines lateral edges of substantially cylindrical shape for its radial holding in position by the ring 14.

[0078] The head 15 is advantageously made of an electrically insulating material, to avoid any parasitic current in the economizer contact.

[0079] The ring 14 advantageously has two deformable ends for fixing by crimping respectively the ring to the rod and the head to the ring.

[0080] For example, the lower end 31 of the ring 14 comprises a thin cylindrical wall surrounding the rod 22 along an axis parallel to the main direction Z, radially deformable in a non-reversible manner to enclose a lower part of the rod extending under the ring 14, so as to block the helical movement of the ring on the rod on their respective threads. This makes it possible to guarantee that the height of the ring 14 and the head 15 is maintained once this height has been adjusted.

[0081] Advantageously, this lower part of the rod defines a flat surface improving the fixing of the ring 14 by clamping.

[0082] Likewise, for example, the upper end 32 of the ring 14 comprises a second thin cylindrical wall radially surrounding the head 15 and the upper edges of which extend beyond the lateral edges of said head 15. This second wall is irreversibly deformable around the lateral edges of the head 15 in order to lock said head 15 in position both axially along the main direction Z and radially.

Claims

CLAIMS Energy-saving electric contactor (1) comprising a fixed part (2) and a movable part (3) in translation relative to the fixed part (2) along a principal direction (Z), between a contact position of the electric contactor and a breaking position of the electric contactor, the energy-saving electric contactor (1) comprising an elastic blade (8) fixed to the fixed part (2) by a first end and whose second end forms an energy-saving contact, as well as a stop (10) mounted on the movable part (3) and arranged to be away from the blade (8) when the movable part (3) is in its breaking position, the energy-saving contact being then closed, and to bear against the blade (8) when the movable part (3) is in the contact position, the energy-saving contact being then open, characterized in that the fixed part (2) defines an orifice (11) for the passage of the stop (10) opposite the blade (8) along the principal direction (Z),the orifice (11) having an internal cross-section transverse to the principal direction (Z) substantially identical to an external cross-section of the stop (10), the stop (10) being mounted on and the moving part (3) movable in translation in a plane (XY) perpendicular to the principal direction (Z). Energy-saving electrical contactor (1) according to the preceding claim, wherein the fixed part (2) comprises an electrical board (6) on which are mounted the blade (8), by a first end of the blade (8), and a fixed contact (12) disposed at a second end of the blade (8), the orifice (11) being defined in the electrical board (6), opposite the blade (8). Energy-saving electrical contactor (1) according to any one of the preceding claims,in which the stop (10) comprises a foot (13) including a flat portion (21) slidably mounted between a support (16) and an auxiliary blade (5) of the movable portion (3). Energy-saving electrical contactor (1) according to the preceding claim, in which the support (16) comprises a recess (27) receiving the flat portion (21), the auxiliary blade (5) defining an opening (23) opposite the recess (27), the stop (10) extending through the opening (23) in the direction of the passage orifice (11). Energy-saving electrical contactor (1) according to any one of the preceding claims, in which the stop (10) comprises a threaded rod (22) extending in the principal direction, (Z) and a head (15) mounted on the rod (22) and adjustable in height relative to the rod (22) along the principal direction (Z). Energy-saving electrical contactor (1) according to the preceding claim, wherein the stop (10) comprises a threaded ring (14) engaged on the threaded rod (22) and carrying the head (15). Energy-saving electrical contactor (1) according to the preceding claim, wherein the ring (14) has a circular outer section having a first radius, the passage orifice (11) having a circular inner section having a second radius, the first radius being smaller than the second radius by a clearance adapted to prevent the passage of dust. Energy-saving electrical contactor (1) according to any one of claims 5 to 7, wherein the head (15) has a bump (30) oriented towards the blade (8) along the principal direction (Z).Energy-saving electrical contactor (1) according to any one of claims 5 to 8, wherein the head (15) is made of insulating material. Energy-saving electrical contactor (1) according to any one of claims 5 to 9, wherein the stop (10) comprises means (31, 32) for blocking the movement of the head (15) relative to the rod (22).

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