WO2019159022A1

WO2019159022A1 - Control mechanism for switches and the like

Info

Publication number: WO2019159022A1
Application number: PCT/IB2019/050597
Authority: WO
Inventors: Volpato Alberto; Cavalli Antonio
Original assignee: Vimar S.P.A.
Priority date: 2018-01-24
Filing date: 2019-01-24
Publication date: 2019-08-22
Also published as: IT201800001759A1

Abstract

A control mechanism for switches and the like includes a frame, a button for actuating the control mechanism, a piston supported in a rocking manner on the frame about a switching axis and connected in a spring-mounted manner to the button, a support for a moveable contact articulated on the piston and pushed by the piston against a contact surface which is an integral part of the frame, a corresponding fixed contact connected to the frame, the piston and support being able to oscillate about a mutual hinging axis in order to move the moveable contact to and from a closed position on the fixed contact. The support can oscillate to a limited extent with respect to the piston, and between the support and piston there is a mechanical connection which can transfer an initial rocking movement of the button to the support in the form of oscillation of the support in relation to the piston.

Description

CONTROL MECHANISM FOR SWITCHES AND THE LIKE

DESCRIPTION

The present invention relates to a control mechanism for switches and the like which are able to close or switch electrical contacts of the type which comprise the characteristics stated in the preamble to claim 1.

In the technical sector of civil engineering and industrial electrical systems, electro mechanical type switches are commonly used to close or switch electrical contacts, for example for switching light fittings on or off.

In one of their most common configurations, the switches comprise a rocker mechanism activated by manually pressing, which moves a moveable anchor. The movement of the anchor makes it possible to push a flexible conductive strip, taking it from a first position in which an electrical contact is open to a second position in which the contact is closed.

One example of these mechanisms is described in American patent, US 5,436,421 which relates to a switch in which a rocker actuator moves a moveable contact strip by the action of a pin.

The pin is connected to the rocking actuator in such a way that it protrudes towards the moveable contact and, by means of a spring, it is pushed by a spring which rests on the contact itself. Thanks to this configuration, when the rocker actuator is actuated, the pin slides on the contact and causes it to move by oscillating around its central zone.

A further example is described in American patent application US 2005/098420. Some of the known mechanisms based on this operating principle are, however, subject to issues with blocking or other forms of malfunction as a result of continuous switching. In particular, the movement of the pin on the moveable contact is not very fluid and can sometimes be impeded if a permanent deformation of the contact occurs or if it leaves its correct oscillating position.

A further example of the mechanism is represented by patent EP 1430496 in which a compression actuation mechanism is described which also operates with a rocker switch which includes at least one fixed contact and one moveable contact operated by an anchor.

The anchor is actuated in rotation to move the moveable contact closer or further away from the fixed contact using a pin controlled by the rocker switch and pushed against the anchor by a compression spring, in substantially the same way as the previous example.

In this case, however, the pin acts on the anchor with a fork-shaped coupling, secured in a way that allows it to rotate in the opposite way to the rocker switch. In this way, the two branches of the fork are positioned on the corresponding zones of the anchor which are substantially symmetrical in relation to its centre.

The technical problem underlying this invention is therefore to provide a control mechanism for switches or similar devices which is structurally and functionally designed to resolve one or more of the problems reported with reference to the stated prior art.

In respect of this problem, one purpose of this invention is to provide a control mechanism which is particularly reliable and which is unlikely to be susceptible to issues with blocking.

This problem is resolved and one or more of these purposes is achieved by the invention by a control mechanism including a frame, a button for actuating the control mechanism, a piston supported in a rocking manner on the frame relative to a switching axis and connected by a spring to the button, a support for a moveable contact articulated on the piston and pushed by the piston against a contact surface which is an integral part of the frame, a corresponding fixed contact connected to the frame, the piston and support being able to oscillate about a mutual hinging axis in order to move the moveable contact to and from a closed position on the fixed contact, said support being able to oscillate in a limited manner in relation to the piston and in which, between the support and the piston, there is a mechanical connection which transfers an initial tilting movement from the button to the support in the form of the oscillation of the support in relation to the piston. Preferably, the moveable contact is supported in an oscillating manner in a cradle which is an integral part of the primary contact at a contact point of the contact surface in a position opposite the mechanical connection in relation to the mutual hinging axis.

The mechanism of this invention permits prevention or at least limitation of issues of blocking which can occur during the transition phase between the closed position and the closure of the contact or, more generally, during the switching of the switch.

The mechanical connection in fact allows an action to be exerted on the support and therefore on the contact which it moves, to overcome the dead centre, i.e. from one extreme position, or a balanced one, as the moveable assembly formed by the piston and support moves between the two open and closed limit positions of the contact. In some embodiments, the dead centre is the position in which the piston and support are aligned.

Therefore, in a preferred embodiment, the piston and support form a oscillating assembly to overcome the dead centre, the mechanical connection being configured in such a way that the oscillation of the support in relation to the piston is in advance of, and independent from, the overcoming of the dead centre of the piston and support assembly.

In addition, based on another preferred aspect, again for the purposes of unblocking the dead centre and therefore actively avoiding problems with blocking, the mechanical connection is maintained between the piston and support as far as in the vicinity of the dead centre.

In some embodiments, the mechanism comprises a retaining element which limits the ability of the assembly formed by the piston and the support to move, so that, when the assembly of piston and support is made to oscillate by the button, a relative rotation occurs by means of the piston and the support themselves.

In one embodiment, the support comprises an oscillating part which extends from the mutual hinging axis in the opposite direction from the contact surface, the moveable contact being configured in order to contact the oscillating part when placed in the closed position on the fixed contact.

This solution allows for the creation of a particularly compact structure, in particular in terms of its depth, as the position of the contact requires only a minimal movement in the direction away from the axis of articulation. In addition, again thanks to the release capability of the mechanism based on this invention, the switching of the contact can also be achieved with only a relatively short travel of the support, a feature which is particularly advantageous when combined with the specific position of the contact which is in fact pushed directly by the oscillating part of the support.

Again to optimise the dimensions, the support is ideally articulated on one end of the piston at the opposite end from the button.

According to a preferred embodiment, the moveable contact comprises an anchor with two sides that both extend from the same base in substantially a U shape. This anchor is attached to the support by these sides. Preferably, the moveable contact closes on the fixed contact at one of these sides.

It will be appreciated that this solution provides a strong structure and a simple assembly for the mechanism, based on this invention.

In a preferred embodiment, the anchor and cradle are electrically conductive and in reciprocal electrical contact in order to connect the contact to the terminal block to which the electrical wires of the system in which the mechanism is applied are connected.

For the purposes of achieving a sufficiently stable connection between the contact and the support, in some embodiments the anchor has a hole on each side and the support has a corresponding protuberance on each surface facing the corresponding hole, or vice versa, to engage the corresponding hole to retain the anchor on the support.

Preferably, the anchor is supported in an oscillating manner in the cradle which is integrally connected to the primary contact, thereby holding the support appropriately with the moveable contact to achieve the oscillation between the piston and the support about the mutual hinging axis, thus allowing the moveable contact to move to and from a closed position on the fixed contact.

In one embodiment, the mechanical connection between piston and support comprises, on the respective surfaces of the piston and the support, or vice versa, an limb housed in a recess and a collar with at least one end of the recess acting as a stop for the limb. Preferably, the surfaces which form respectively the limb and the recess of each of the aforementioned piston and support are facing. In some embodiments, the recess has a curved shape, with curvature which is preferably centred on the mutual hinging axis of the support. Preferably, the limb is slide- mounted in the curved recess.

This allows the support and the piston to slide precisely, making the switching movement of the mechanism of this invention fluid and precise.

Preferably, both of the circumferential ends of the recess form stops for the limb to act as the mechanical connection, again helping with the precision of movements. In addition, in one embodiment, the limb extends from a slide which partners with the respective surfaces which flank the recess.

To achieve a particularly compact structure which can be assembled simply, in one embodiment the piston comprises a fork with two prongs, at the ends of which said support is articulated, the recess being formed in one wall between the aforementioned prongs.

Preferably, the piston, on the opposite side from the prongs, comprises a coupling part which is slide-mounted in a guide that is an integral part of the button, the springing of the piston being provided between the guide and the coupling part of the piston.

In addition, according to a preferred embodiment, the free ends of the prongs are supported such as to slide on the corresponding juxtaposed collars of the support. In one embodiment, the button is a rocker type.

According to another aspect, the mechanism also comprises a motion conversion mechanism, which can convert the axial movement of the button into the oscillation of the piston.

The properties and further benefits of the invention will become more apparent from the detailed description below of a preferred but not exclusive example of the embodiment illustrated by way of non-limiting indication with reference to the appended drawings in which:

Fig. 1 is an exploded perspective view of a control mechanism for switches and similar devices based on this invention;

Figs. 2A and 2B are two schematic side views in partial cross section which illustrate the control mechanism of this invention in two respective operating positions;

Figs. 3, 4 and 5 are perspective views respectively of a piston, a support and a moveable contact, details of the mechanism from Fig. 1; and

Fig. 6 is a schematic view of an electrical device which comprises the control mechanism as per this invention.

With reference first to Fig. 1, a control mechanism for switches and the like is shown as a whole with the reference number 100.

It will be understood that in this example embodiment, the mechanism is intended to be used in an electrical device of the type commonly referred to as two-way switch or an electrical device which is used to control a piece of electrical equipment, for example a lamp, from two different positions.

To this end, it must be noted that the mechanism according to the present invention may be fitted in a separate module than can be installed on the wall and which can be wired using a specific terminal block, illustrated in the key components in the figure and indicated with the reference number 102, as shown in more detail below.

Fig. 6 shows the basic components of an electrical device on which the control mechanism 100 is used, denoting the whole with the reference number 200.

In general, it must be noted that the mechanism of this invention may also be applied to other devices for electrical systems, for example switches, three-way switches, push buttons and the like.

Again with reference to Fig. 1, the control mechanism 100 comprises a frame 101 on which is supported, preferably in a rocking manner, a button 1 which is used to actuate the control mechanism 100.

Preferably, the frame 101 is connected to the casing 201, as can be seen in Fig. 6, of the piece of equipment on which device 100 is used. Note also that the button 1 may comprise a button cover 10 which is also shown in Fig. 6. These components are, however, only shown in diagram form as they themselves have known characteristics.

As indicated above, in a preferred embodiment, the button 1 is a rocker button and, as such, it is supported on the frame 101 using a pair of pins 11 accommodated in the corresponding seats 110 formed on the frame. In one embodiment, the pins 11 are wedge shaped, with the peak facing the outer face of the button, with the seats 110 having a complementary shape.

More generally, the connection between frame and button will be made in a way that allows for limited oscillation about a switching axis C, thereby providing the rocking movement.

In an alternative embodiment, the button 1 may have an axial movement. In other words, in this case the switching occurs by pushing the button in an axial direction, specifically along an axis which is substantially perpendicular to the plane defined by the button itself, rather than by a rocking movement.

The mechanism 100 also comprises a piston 2, with a spring-mounted connection to the button 1. In one embodiment, the piston 2 is spring-mounted on button 1. To this end, in one embodiment of the invention, the piston 2 may perform motions towards and away from button 1 and, by means of a spring, or another resilient element 12, it is urged away from the button.

Note that, for a button with axial movement, the mechanism 100 comprises a motion conversion mechanism which can convert the axial movement, i.e. a linear movement, of the button into the oscillation of the piston. One example of this mechanism is described in the patent application EP2672498 in the name of the same applicant.

A support 3 is articulated on the piston 2 to which a moveable contact 4 is connected.

Preferably, the support 3 is articulated on one end of the piston 2 at the opposite end from the button 1.

In a preferred embodiment, the moveable contact 4 is able to close an electrical contact onto fixed contact 5, which itself is connected to the frame 101, thus electrically connecting the electrical wires connected to the terminal strip 102. Preferably, the moveable contact 4 is in contact with a contact surface 60 of a primary contact 6 on which one of the terminal blocks 102 is connected, in order to connect the electrical power supply cable, generally the phase cable, of the device to be controlled, using the mechanism of the invention. More generally, it must be observed that the moveable contact 4 is pushed by the piston 2 against the contact surface 60 which is an integral part of the frame 101.

In some embodiments, the moveable contact 4 may meet the contact surface 60 in such a way that it is supported in an oscillating manner in a cradle 61 which is an integral part of the primary contact 6 at one contact point 60A.

As can be seen from the figures, in one embodiment the contact surface 60 extends from the primary contact 6 so that the cable connected to the primary contact 6 is electrically connected to the moveable contact 4. It will be appreciated that by pushing the moveable contact 4 against the contact surface 60, it is possible to maintain the electrical connection during the oscillation of the moveable contact 4 and the associated movement.

As can be seen in the figures, in particular Figs. 1 and 2B, the piston 2 and the support 3 can oscillate about a mutual hinging axis X, preferably in a rocking manner, in order to move the moveable contact 4 to and from a closed position on the fixed contact 5.

Based on such a configuration, as can be seen in Figs. 2A and 2B, the oscillating movement of the button 1 produces a corresponding oscillation of the assembly formed by the piston 2 and the support 3. However, the support 3, connected to the moveable contact 4, being pushed against the contact surface 60, is held on the contact surface 60 itself. To this end, provision may be made for the presence of a specific retention element which limits the ability of the assembly formed by the piston and the support to move. As will be better illustrated below, in one embodiment the retention element comprises a cradle 61 in which the moveable contact 4 is held, however different solutions may also be envisaged. For example, the retention element may also be created by the same friction as is generated by the force with which the resilient element 12 pushes the piston 2.

Therefore, since the moveable contact is partially constrained, the oscillation of the button 1 will cause a rotation of the support 3 in relation to the piston 2 about the mutual hinging axis X, thus limiting the oscillation of the support 3 in relation to the piston 2.

Thanks to this movement, the moveable contact 4 can be moved from its initial position where the contact with the fixed contact 5 is open, as shown in Fig. 2A, to a second position in which the aforementioned contact is closed, as shown on the other hand in Fig. 2B.

Note that, in the embodiment illustrated in the figures, the mechanism comprises an auxiliary contact 8 onto which the moveable contact 4 closes in the first position. The presence of the auxiliary contact 8 allows an electrical connection to be closed between the primary contact 6 and an additional deflector device when the contact between the moveable contact 4 and fixed contact 5 is open, in order to produce the circuit required to control a light from two separate positions.

It will be appreciated that the auxiliary contact 8 may not be present in the event that it is not required by the device on which the mechanism of this invention is used.

According to a first aspect of the invention, the control mechanism comprises a mechanical connection 7 positioned between support 3 and piston 2 which transfers an initial axial tilting movement of the button 1 to the support 3 in the form of oscillation of the support 3 in relation to the piston 2.

In some embodiments, the contact point 60A, where the moveable contact 4 is supported in an oscillating manner, is located in the position opposite the mechanical connection 7 in relation to the mutual hinging axis.

Note that this arrangement allows for the support 3 to be properly retained with the moveable contact 4 against the primary contact 6 to provide the oscillating motion between the piston 2 and the support 3 about the mutual hinging axis X in a rocking manner in order to move the moveable contact 4 to and from a closed position against the fixed contact 5.

In other words, the mutual hinging axis X is not in a fixed position but oscillates between two limit positions.

In a preferred embodiment, the mechanical connection 7 between the piston 2 and support 3 comprises an limb 31 housed in a recess 21 and a collar 22 at at least one end of the curved recess 21, acting as a stop for the limb 31. The limb 31 and recess 21 are formed respectively on the support 3 and piston 2, or vice versa, preferably where the respective facing surfaces are.

In one embodiment, the recess 21 is curved in shape, centred on the mutual hinging axis X of the support 3, in such a manner that the limb 31 can be slide- mounted in the recess.

The mechanical connection 7 may therefore be usefully obtained by using one or both ends of the recess 21 in order that they form the stops for the motion of the limb 31. Preferably, the limit positions of the axis of articulation X are defined by the two aforementioned stops.

More generally, the mechanical connection 7 can be configured so that the oscillation of the support 3 in relation to the piston 2 takes place in advance of, and independently from overcoming the dead centre of the assembly formed by the piston 2 and support 3. This dead centre, like the motion of a piston in the respective cylinder, corresponds to a position in which the piston 2 and support 3 are aligned. Note that, in this position, the axis of articulation C of the button, the mutual hinging axis X and the contact point between the moveable contact 4 and the contact surface are aligned.

To make the movement between the support 3 and the piston 2 more smooth and precise, in some embodiments the limb 31 may be extended by a slide 32, as shown in Fig. 4, which cooperates with a respective surface 26, shown in Fig. 2B, flanking the curved recess 21.

In addition, in one embodiment, the mechanical connection 7 is advantageously configured so that it is maintained between piston 2 and support 3 even as far as the vicinity of the dead centre.

Based on another aspect of the invention, the support 3 comprises an oscillating part 30 which extends from the mutual hinging axis X in the opposition direction from the contact surface 60.

Preferably, the moveable contact 4 comprises an anchor 40 with two sides 41 which both extend from a single base 42 that is substantially U-shaped.

The sides 41, as will be illustrated more clearly below, are used to connect the anchor 40 to the support 3.

In a preferred embodiment, the moveable contact 4 closes on the fixed contact 5 where one of the sides 41 is so that, when in this position, the side 41 contacts the surface facing it of the oscillating part.

More generally, in the mechanism according to this invention, the moveable contact 4 can be configured so that it contacts the oscillating part 30 when placed in the closed position on the fixed contact 5 and/or in the closed position on the auxiliary contact 8, where present.

In this way, in contrast to what happens with the known mechanisms, contacts which require a significant deformation to achieve the closure of the contact can be avoided.

With reference to Figs. 4 and 5, according to a preferred embodiment, the anchor 40 has a hole 43 on each side 41 and the support 3 has a corresponding protuberance on each surface facing the corresponding hole 43, or vice versa, to engage the corresponding hole 43 in order to retain the anchor 40 on the support 3.

In addition, according to a preferred embodiment, the cradle 61 may be configured so that it supports the anchor 40 in an oscillating manner. For example, the cradle 61 may have extensions 62 between which a profiled part 44 is engaged formed on the base 42 of the anchor 40. More generally, the cradle 61 can be configured so that it allows the moveable contact 4 to oscillate and prevents or limits linear movements of said contact.

Preferably, the cradle 61 is integrally connected to the primary contact 6 and the anchor 40 and the cradle 61 are electrical conductors and in reciprocal electrical conductive contact.

With reference to Fig. 3, the piston 2 comprises, preferably, a fork 23 with two prongs 24, at the respective ends of which the support 3 is articulated. It will be understood that, within the context of this invention, the term piston is used to indicate a moveable element, with predominately axial movement, able to slide within a respective channel and not necessarily having a cylindrical shape.

The recess 21 on which the limb 31 slides is preferably formed between the prongs 24, which optimises the dimensions of the structure.

In one embodiment, the piston 2, on the opposite side from the prongs 24, comprises a coupling part 25 which is slide-mounted in a guide 15 that is an integral part of the button 1. The springing of the piston 2 is preferably provided between the guide 15 and the coupling part 25 of the piston 2, with the resilient element 12 held by a pin 28 which protrudes from the coupling part.

In a preferred embodiment, the free ends 27 of the prongs 24 slide freely on the corresponding juxtaposed collars 36 of the support 3.

The invention thus resolves the problem presented, whilst at the same time offering a range of benefits. In particular, the control mechanism according to this invention enables switches, deflectors, inverters and similar devices to be produced in which the possibility of blocking can be minimised and which have particularly small overall dimensions for the housing where they are installed, i.e. in the direction of their depth.

Claims

1. Control mechanism (100) for switches and the like, comprising:

- a frame (101 );

- a button (1 ) for actuating the control mechanism (100);

- a piston (2) which is supported on the frame (101 ) such that it can tilt with respect to a switching axis (C) and is connected to the button (1 ) in a spring- mounted manner;

- a support (3) for a movable contact (4), which is hinged to the piston (2) and is urged against a contact surface (60), which is integral with the frame (101 ), by means of the piston (2);

- a corresponding fixed contact (5) connected to the frame (101 );

- it being possible to oscillate the piston (2) and the support (3) about a mutual hinging axis (X) so as to move the movable contact (4) from and into a closed position on the fixed contact (5),

it being possible to oscillate said support (3) to a limited extent with respect to the piston (2), said movable contact (4) being supported such that it can oscillate in a cradle (61 ) that is integral with a primary contact (6) at a contact point (60A) of said contact surface (60) that is arranged in a position opposite said mechanical connection (7) with respect to said mutual hinging axis (X).

2. Control mechanism (100) according to claim 1 , wherein the piston (2) and the support (3) form one entity which can oscillate so as to pass over a dead centre, said mechanical connection (7) being designed such that the oscillation of the support (3) with respect to the piston (2) is anticipated and is independent of the entity, which is formed by the piston (2) and the support (3), passing over said dead centre.

3. Control mechanism (100) according to claim 2, wherein the mechanical connection (7) is designed so as to be held between the piston (2) and the support (3) until close to the dead centre.

4. Control mechanism (100) according to any one of the preceding claims, wherein said support (3) comprises an oscillating portion (30) which extends from the mutual hinging axis (X) in the opposite direction to the contact surface (60).

5. Control mechanism (100) according to claim 4, wherein the movable contact (4) is designed so as to contact said oscillating portion (30) when arranged in the closed position on the fixed contact (5).

6. Control mechanism (100) according to any one of the preceding claims, wherein the movable contact (4) comprises an anchor (40) having two sides (41), which both extend from a common base (42) in the shape of a U, said anchor (40) being connected to the support (3) by means of said sides (41).

7. Control mechanism (100) according to claim 4 or claim 5 and claim 6, wherein one of said sides (41) of the movable contact (4) closes onto the fixed contact (5).

8. Control mechanism (100) according to one or more of the preceding claims, wherein said mechanical connection (7) between the piston (2) and the support (3) comprises, on respective surfaces of the piston (2) and the support (3), or vice versa, a limb (31) that is received in a recess (21), and a shoulder (22), which acts as a stop for said limb (31), at at least one end of the recess (21).

9. Control mechanism (100) according to claim 8, wherein the surfaces that form the limb (31) and the recess (21) respectively on each of the pistons (2) and the support (3) are facing one another.

10. Control mechanism (100) according to either claim 8 or claim 9, wherein said recess (21) has a curved shape.

1 1. Control mechanism (100) according to claim 10, wherein the centre of the curvature of said recess (21) is on the mutual hinging axis (X) of the support (3).

12. Control mechanism (100) according to any one of claims 8 to 1 1, wherein the limb (31) is received in a sliding manner in the recess (21).

13. Control mechanism (100) according to any one of claims 8 to 12, wherein the circumferential ends of the recess (21) provide stops for the limb (31), in order to create said mechanical connection (7).

14. Control mechanism (100) according to any one of claims 8 to 13, wherein the limb (31) extends from a slide (32) which cooperates with a particular surface (26) that borders the recess (21).

15. Control mechanism (100) according to any one of claims 8 to 14, wherein said piston (2) comprises a fork (23) having two prongs (24), to the respective ends of which the support (3) is hinged, said recess (21) being formed between said prongs (24).

16. Control mechanism (100) according to claim 15, wherein the piston (2) comprises, on the opposite side to the prongs (24), a coupling portion (25) that is slidably received in a guide (15) that is integral with the button (1), the spring of the piston (2) being provided between the guide (15) and said coupling portion (25) of the piston (2).

17. Control mechanism (100) according to any one of the preceding claims, wherein said dead centre is reached in a position in which the piston (2) and the support (3) are aligned.

18. Control mechanism (100) according to any one of the preceding claims, also comprising a motion conversion mechanism that can convert a linear movement, in an axial direction, of the button (1) into an oscillation of the piston (2).

19. Control mechanism (100) according to any one of the preceding claims, wherein said support (3) and said one movable contact (4) are urged against said contact surface (60), so that the mutual hinging axis (X) oscillates between two limit positions during movement of the movable contact (4) from and into a closed position on the fixed contact (5).

20. Control mechanism (100) according to any one of the preceding claims, wherein said piston (2) is configured so as to carry out movements towards/away from the button (1 ), and is urged away from the button (1 ) by means of a resilient element (12).

21. Control mechanism (100) according to claim 20, wherein said piston (2) comprises a coupling portion (25) that is received in a sliding manner in a guide (1 5) that is integral with the button (1 ), the spring of the piston (2) preferably being provided between the guide (1 5) and the coupling portion (25) of the piston (2).