FR3107402A1 - NORMALLY CLOSED TYPE ELECTRIC SWITCH WITH AN INITIAL DELIVERY STATE WITH OPEN CONTACT - Google Patents

Abstract

The invention proposes a switch (100) comprising an insulating body (20) of which an upper part (36) carries a fixed contact track (72), an elastically deformable contact blade (48) which comprises a mobile section (90) contact which can occupy an initial open low position, a first closed stable high position in which the movable contact section (90) is resting in contact on the fixed track (72), and a second open unstable high position, and wherein the contact blade (48) comprises a section (84) for controlling the elastic deformations of the contact blade (48) to cause upward vertical displacements of the movable contact section (90) from its initial position low or from its first high position. Figure for abstract: 8

Description

ELECTRICAL SWITCH OF THE NORMALLY CLOSED TYPE HAVING AN INITIAL STATE OF DELIVERY WITH OPEN CONTACT

Technical field of the invention

The invention relates to an electrical switch of the normally closed type comprising an elastically deformable contact blade which causes a change of state of the electrical switch in response to the application of an actuation force on the elastically deformable blade and in which, in the absence of application of an actuation force, the electrical switch is maintained in a closed state.

Technical background

In such a type of electrical switch, in the absence of a force acting on the elastically deformable contact blade, the electrical switch is maintained under load in its closed state.

After the integration of such a type of electrical switch in an electronic or electromechanical device, its conventional use consists in interrupting the electrical switching path by acting on the elastically deformable contact blade before the first use or functional start-up of the device. 'device.

The device can then be stored for a period that can be very long, without energy consumption.

During the first use causing at least a first change of state of the electrical switch, the latter returns at least temporarily to its closed state in which the electrical switching path is established.

Such a design can be inconvenient, in particular when the electric switch is assembled on an electronic card comprising a battery or electric cell. Indeed, before being integrated into the electronic device, the electric switch is not activated and it is in its closed state, which causes consumption of the energy accumulated in the battery or electric cell of the device. .

The invention aims to provide a solution to this problem by proposing an electrical switch whose design makes it possible to ensure locking in the open position, that is to say in a state in which the electrical switching path is interrupted.

The invention also aims to provide such an electric switch which is of compact design, and which makes it possible to absorb an overtravel of actuation.

The invention also aims to propose a switch which can be unlocked automatically when it is carried by a sub-assembly which is put in place and assembled in an electronic device.

The invention proposes an electrical switch of the normally closed type comprising:
- A body made of insulating material, an upper part of which carries a fixed contact track;
- an elastically deformable contact blade, which is carried by the body, and which comprises a mobile contact section which can occupy:
* an initial low position in which the movable contact section is arranged below the fixed contact track and in which the electrical switching path between the fixed track and the movable section is interrupted;
* a first stable high position in which the movable contact section is arranged above the fixed track and is in elastic contact support on a portion vis-à-vis the fixed track to establish said switching path;
* a second unstable upper position in which the movable contact section is arranged above and at a distance from the fixed track and in which said electrical switching path is interrupted;
and in which the contact blade comprises a section for controlling the elastic deformations of the contact blade to cause upward vertical displacements of the movable contact section from its initial low position or from its first high position.

According to other switch features:
- the low position of the movable contact section corresponds to an initial state of delivery of the electrical switch;
- the contact blade comprises successively:
* a section for fixing it to the body made of insulating material;
* an intermediate section for controlling the elastic deformations of the contact blade;
* and the mobile contact section;
- the movable contact section is a free end section of the contact blade;
- The intermediate control section is able to pivot relative to the fixing section around a horizontal axis;
- the intermediate control section (84) is a lower control elbow (84) whose convexity is oriented vertically downwards;
- the fixed track is an upper face of a fixed contact section of an electrical connection blade carried by the body made of insulating material, which extends in line with the movable contact section, and the upper part of the insulating body and / or the movable contact section comprises a control cam for crossing the fixed contact section when the movable contact section moves vertically upwards from its initial position;
- during the vertically upward travel of the mobile contact section from its initial low position, the crossing of the fixed contact section takes place without establishing the electrical switching path between the fixed track and the mobile contact section ;
- The fixed track is a horizontal upper face of said fixed contact section.

The invention also proposes an assembly comprising an electronic card and a switch according to the invention, characterized in that the electrical switch is mounted on one face of the electronic card and is adjacent to an edge of the electronic card so that, if the assembly is placed in an electronic device, the internal contact blade of the electrical switch is automatically unlocked by its elastically deformable contact blade coming into contact with a part facing the electronic device, or belonging to assembly means.

Brief description of figures

Other characteristics and advantages of the invention will appear during the reading of the detailed description which will follow for the understanding of which reference will be made to the appended drawings in which:

- Figure 1 is a perspective view of an embodiment of an electrical switch according to the invention which is illustrated in which the movable contact section is shown in its initial low position;

– Figure 2 is a side view of the electrical switch shown in Figure 1;

- Figure 3 is a top view of the electrical switch shown in Figure 1;

- Figure 4 is a bottom view of the electrical switch shown in Figure 1;

- Figure 5 is a view of the rear face of the electrical switch shown in Figure 1;

– Figure 6 is a large-scale perspective view of detail D6 of Figure 1;

- Figure 7 is a perspective view of the contact blades and connection of the electrical switch shown in Figure 1;

- Figure 8 is a sectional view through the vertical plane 8-8 of Figure 3;

- Figure 9 is a front view of the electrical switch shown in Figure 1;

- Figure 10 is a view similar to that of Figure 9 in which the movable contact section is shown in its second unstable upper position;

- Figure 11 is a view similar to that of Figure 9 in which the movable contact section is shown in its first unstable high position;

- Figure 12 is a perspective view illustrating the electrical switch shown in Figures 1 to 9, in the assembled position on one side of a card or printed circuit board.

Detailed description of the invention

For the description of the invention and the understanding of the claims, the vertical, longitudinal and transverse orientations according to the reference V, L, T indicated in the figures whose longitudinal axes L and transverse T extend in a horizontal plane.

In the following description, identical, similar or analogous elements will be designated by the same reference numerals.

The electric switch 100 illustrated in the figures comprises a body 20 made of insulating plastic material, here by molding in one piece.

The body 20 is of generally rectangular parallelepipedal shape and it is here molded onto a set 22 of conductive blades which are here produced by cutting and bending in a sheet of conductive material, for example metal.

Alternatively, the conductive blades can be made of another material coated with an electrically conductive layer.

The body 20 is delimited by two main vertical and longitudinal front 24 and rear 26 faces, by two vertical and transverse side faces on the left 28 and on the right 30 (considering the orientation of FIGS. 8 to 11), and by two horizontal faces upper 32 and lower 34.

By way of example and to allow its positioning and fixing for example on a printed circuit board, the body 20 here comprises two pins 35 which extend vertically below the lower horizontal face 34.

At its upper end, the body 20 has an extension 36 which extends transversely forward beyond the vertical plane of the main front face 24.

The extension 36 is delimited by an upper horizontal face 38 which extends in the plane of the upper face 32, and by a lower horizontal face 40.

At its right longitudinal end, the lower horizontal face 40 is extended by an inclined planar surface portion 41 forming a ramp so that the right longitudinal portion of the extension 36 constitutes a cam with a flat and inclined lower cam profile 41.

Thus, as can be seen in particular in Figure 2, there is a free vertical space 42 below the extension 36 which is adjacent to the main front face.

The set 22 of conductive blades consists of a first subset 44 and a second subset 46.

The assembly 22 comprises three main blades, including an elastically deformable electrical contact front blade 48 which extends in a vertical and longitudinal plane in the free vertical space 42.

The assembly 22 further comprises two rear blades for electrical connection on the left 50 and on the right 52.

Each rear electrical connection blade 50, 52 extends vertically along an adjacent side face 28, 30 respectively of the body 20, over its entire height.

At its lower end, each rear electrical connection blade 50, 52 is extended by an angled electrical connection spout 54, 56 which is positioned in a complementary housing 58, 60 of the body 20 and of which a convex lower surface portion 62, 64 is arranged to come into electrical contact with a conductive track (not shown) of a surface portion facing one face of an electronic card comprising in particular a printed circuit board.

At its upper end, the rear right-hand electrical connection blade 52 is extended by a horizontal and longitudinal branch 66, a portion of the upper surface of which is cleared 68, allowing electrical test operations.

In its horizontal plane, the horizontal and longitudinal branch 66 is extended transversely forward by a horizontal plate 70 which extends through the upper extension 36.

The horizontal plate 70 is arranged vertically above the right longitudinal portion of the extension 36 comprising the cam with a flat and inclined lower cam profile 41.

The upper face of the horizontal plate is cleared, that is to say it is not covered with insulating material and it constitutes a fixed upper conductive track 72.

The fixed track 72 is here a flat and horizontal track which is conductive and which is electrically connected to the lower right-hand electrical connection bent 56.

At its upper end, the rear left-hand electrical connection blade 50 is extended by a horizontal and longitudinal branch 76, a portion of the upper face of which is cleared 78 of which allows electrical test operations.

In its horizontal plane, the horizontal and longitudinal branch 78 is extended transversely forward by a horizontal transverse connecting branch 80 which extends through the upper extension 36.

The connecting branch 80 structurally and electrically connects the rear left electrical connection blade 50 to the elastically deformable electrical contact front blade 48 which extends into the free vertical space 42.

In FIGS. 1 to 9, the elastically deformable rear left electrical connection blade 50 is shown in its undeformed free state.

The front contact blade 48 is thus mounted cantilevered relative to the body 20.

From the connection branch 80, the contact blade 48 comprises successively:
- A left side section 82 for its fixing and its support by the body 20 of insulating material;
- a bent intermediate section 84 for controlling the elastic deformations of the front contact blade 48
- And a lateral and vertical right section 86 which carries a mobile contact section.

The left side fixing section 82 is inclined substantially at a 45 degree angle from top to bottom and from left to right.

The bent intermediate section 84 is a lower section whose convexity is oriented downwards.

It comprises a lower vertex of which a convex lower control surface portion 88 is arranged vertically below the plane of the horizontal lower face 34 of the body 20.

At its upper end, the lateral and vertical section on the right 86 (Which is the mobile contact section of the electric switch 100) is extended by an angled and folded upper beak 90 at the free end which extends generally longitudinally towards the left.

The upper beak 90 of the contact blade 48 constitutes the movable contact section of the contact blade 48 which, within the meaning of the invention, is capable of occupying at least three functional positions including a low initial position which is that represented in figures 1 to 9.

The free upper face of the upper beak 90 is a portion of inclined planar surface 92 forming a ramp so as to constitute a cam follower element which is capable of cooperating with the lower cam profile, flat and inclined, 41 of the transverse extension 36 of the body. 20.

As can be seen in particular in Figures 6 and 8, the inclined surface portions 41 and 92 are substantially parallel and are spaced vertically from each other.

To allow the cooperation of these two inclined surface portions 41 and 92, they are arranged vertically one above the other.

Finally, the upper beak 90 is delimited longitudinally by a free end transverse edge 94 which, as can be seen in FIG. portion facing the upper fixed conductive track 74 of the upper face 72 of the horizontal plate 70.

The operation of the electrical switch 100 is as follows.

In FIGS. 1 to 9, the switch 100 is shown in an initial rest position in which the electrical switching path between the two connecting blades 50 and 52 is interrupted, that is to say that – in this initial state of delivery – electrical switch 100 is open.

From this initial open state, and to cause a change of state of the electrical switch, elastic deformations of the contact blade 48 must be applied to the control elbow 84, an actuation force generally vertically upwards according to the arrow F shown in Figure 9.

Such a force can be applied directly in the vertical direction or can result from a longitudinal course of the elbow 84 along an inclined ramp.

The force F applied to the elbow 84 causes an overall pivoting of the contact blade 48 (counterclockwise considering Figure 9) around a horizontal axis AH located in the upper left corner of the contact blade 48.

This pivoting causes a substantially vertical stroke upwards of the mobile section 90 of contact.

During this travel, the upper face 92 comes into contact with the insulating lower face 41 of the upper extension 36 of the body 20.

By a cam effect, the cooperation of the two surfaces 41 and 92 causes a longitudinal displacement to the right of the mobile contact section 90, by elastic deformation of the blade 48 of contact.

During this phase of crossing the fixed track 70 by the mobile section 90, there is no electrical contact between these two elements and the electrical switch 100 remains in an open state.

By continuing to continuously apply the force F - vertically upwards - the crossing of the fixed contact section 70 is carried out by the mobile contact section 90 which is carried out without establishing the electrical switching path between the fixed track 72 and the movable section 90 of contact.

The vertically upward stroke can thus continue up to the high position illustrated in FIG. 10 in which the movable contact section 90 is arranged above and at a distance from the fixed track 72 and in which the electrical switching path is always interrupted and the electric switch 100 is always in an open state.

This high position is not stable, i.e. it can only be maintained if the application of the force F is maintained.

If one removes or if one releases the application of the vertical force F, by an elastic return effect resulting from the energy accumulated in the contact blade 48, the contact blade 48 pivots globally around the axis AH clockwise.

This pivoting causes a substantially vertical downward stroke of the movable section 90 of contact.

During this race, the free end edge 94 of the mobile contact section 90 comes into elastic support on the fixed track 72.

Thus, the electrical switching path is established between the two connecting strips 50 and 52 and the electrical switch 100 is in a state called normally closed.

This is a stable state - shown in Figure 11 - of the contact blade 48 and the electrical switch 100.

From this normally closed stable state, it is possible to actuate the electric switch 100 to bring it again into the position illustrated in FIG. 10, or into an intermediate position in which the electric switch 100 is again in a open state.

If after having brought the electric switch 100 into the position illustrated in FIG. 10 (for example to test the correct operation of the switch and/or of the electrical initial said delivery illustrated in Figure 9, it is necessary to act voluntarily and manually on movable section 90 to move it longitudinally to the right so that it escapes and is then elastically returned downwards.

As can be seen in Figure 12, an electrical switch 100 according to the invention can be mounted on a face 104 of an electronic card comprising in particular a printed circuit board 102 which is delimited by a side edge 106 to constitute a set 200.

The switch 100 and its contact blade 48 are illustrated in their initial state, said to be on delivery.

The switch 100 is close to the side edge 106 of the plate 102 and the main front face 24 of the body 20 is substantially aligned with the side edge 106.

Such mounting and positioning of the electrical switch 100 can, if the assembly 200 is placed in an electronic device (not shown) in the direction indicated by the arrow F of FIG. 12, allow an automatic change of state of the switch electric 100 by the coming into contact of the control elbow84 with a part vis-à-vis the electronic device, or belonging to automated assembly means.

Claims (10)

Electrical switch (100) of the normally closed type comprising:
- a body (20) of insulating material, an upper part (36) of which carries a fixed contact track (72);
- an elastically deformable contact blade (48), which is carried by the body (20), and which comprises a mobile contact section (90) which can occupy:
* an initial low position in which the movable section (90) of contact is arranged below the fixed track (72) of contact and in which the electrical switching path between the fixed track (72) and the movable section (90 ) is interrupted;
* a first stable high position in which the movable section (90) of contact is arranged above the fixed track (72) and is in elastic contact support on a portion vis-à-vis the fixed track (72 ) to establish said switching path;
* a second unstable upper position in which the movable contact section (90) is arranged above and at a distance from the fixed track (72) and in which said electrical switching path is interrupted:
and in which the contact blade (48) comprises a section (84) for controlling the elastic deformations of the contact blade (48) to cause upward vertical displacements of the movable contact section (90) from its position initial low or from its first high position. Electric switch (100) according to Claim 1, characterized in that the said low position of the movable contact section (90) corresponds to an initial delivery state of the electric switch (100). Electrical switch (100) according to Claim 1, characterized in that the contact blade (48) comprises successively:
- a section (82) for fixing it to the body (20) of insulating material;
- an intermediate section (84) for controlling the elastic deformations of the contact blade (48);
- And said movable section (90) of contact. Electrical switch (100) according to Claim 3, characterized in that the movable contact section (90) is a free end section of the contact blade (48). Electric switch (100) according to Claim 3, characterized in that the intermediate control section (84) is capable of pivoting with respect to the fixing section around a horizontal axis. Electric switch (100) according to Claim 3, characterized in that the intermediate control section (84) is a lower control elbow (84) whose convexity is oriented vertically downwards. Electrical switch (100) according to claim 6,
characterized in that the fixed track (72) is an upper face of a fixed contact section (70) of an electrical connection blade (52) carried by the body (20) made of insulating material, which extends right of the mobile contact section (90),
and in that the upper part of the insulating body (20, 36) and/or the mobile contact section (90) comprises a cam (41) for controlling the crossing of the fixed contact section (70) when the mobile section (90 ) of contact moves vertically upwards from its initial position. Electrical switch (100) according to Claim 7, characterized in that, during the vertically upward travel of the movable contact section (90) from its initial low position, the crossing of the fixed contact section (70) s 'performs without establishing the electrical switching path between the fixed track (72) and the movable section (90) of contact. Electrical switch (100) according to one of Claims 7 or 8, characterized in that the fixed track (72) is a horizontal upper face of the said fixed contact section (70). Assembly (200) comprising an electronic card (102) and a switch according to any one of the preceding claims, characterized in that the electrical switch (100) is mounted on one face (104) of the electronic card and is adjacent to an edge (106) of the electronic card (102) so that, if the assembly (200) is placed in an electronic device, the elastically deformable contact blade (48) is automatically unlocked of the electrical switch (100) by the coming into contact of a control section (84) of the elastically deformable contact blade (48) with a part facing the electronic device, or with a part belonging to assembly means.