AU2004212581B2 - An electromechanical remote switch - Google Patents

Description

P001 Section 29 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: An electromechanical remote switch The following statement is a full description of this invention, including the best method of performing it known to us: AN ELECTROMECHANICAL REMOTE SWITCH FIELD OF THE INVENTION The invention relates to an electromechanical remote switch, comprising at least one fixed contact and a monostable movable contact which cooperates with the same, is arranged on a slide and may be displaced by the same relative to the fixed contact, and to a magnetic system with an energising coil and an armature which may be displaced by the same and is coupled to the slide, which slide is pressed in the direction towards a first switch position by means of a return spring.

BACKGROUND OF THE INVENTION Such remote switches can be provided in two different versions which differ by their switching behaviour. On the one hand, monostable remote switches are known which are always retained in a first switching position by the return spring and can assume a second switching position only as long as a sufficiently large voltage is applied to the energising coil. Such remote switches are also known as relays or contactors.

Bistable remote switches (which are also known as remote-control switches) on the other hand can maintain two switching positions in a stable fashion even when their energising coil is de-energised. A voltage impulse or a current impulse applied to the energising coil is merely required for switching over from the one switching position to the other switching position.

A pushbutton switch mechanism is described in US-PS 4,404,444 which comprises a housing to which connecting terminals are fixed. The second essential component of the mechanism is a slider which is received displaceably in the direction of its longitudinal axis in a recess of the housing. Said slide carries contact plates on the side walls, by means of which electric connections between the connecting terminals can be produced. A helical spring which encloses the slide and rests with its first end on a shoulder of the slide and with its other end on the face side of the housing, pretensions the slide in the direction away from the housing. A heart-shaped cam groove (cf. fig. 2) is incorporated in the upper side of the slide, which groove cooperates with a double-L-shaped stop member. The first upwardly extending leg acts as a pivot pin and is held in a bore of the housing. The second, downwardly extending pin engages in the heartshaped cam groove (cf. fig. As a result of the cooperation of the stop member with the heart shaped cam groove the slide assumes two stable positions, i.e. in the case of displacements in the direction of its longitudinal axis. The switch can be converted relatively easily into a monostable switch by simply removing the stop member.

FR-A-2 014 488 describes an electromagnetic switch with a magnet coil, an L-shaped yoke and a clapper swivellably held on the same. Said clapper displaces a switch lever extending parallel to the longitudinal axis of the coil and carrying a pin. A slide is arranged parallel to the switch lever which presses with its free end on contact springs. A recess in form of an isosceles triangle is incorporated in the slide, which triangle is provided in the zone of its hypotenuse with a step. The pin engages in said triangle. A ratchet lever is situated on the side of the slide facing the magnet coil, which ratchet lever is connected with the slide so as to be swivellable about the axis. Said ratchet lever is provided at its free end with a nose situated in the zone of the triangular recess. The further lever is located on the other side of the slide, which further lever comprises an inclined plane in the zone of the recess which projects into the recess. A bistable switching behaviour is obtained as follows: During the attraction of the armature the pin rests in the step and displaces the slide downwardly. The nose of the ratchet lever reaches below a fixed point arranged on the coil body flange and is swivelled by the pretensioning of the lever through the spring behind said fixed point, as a result of which the slide is latched in this position. During the release of the armature the pint slides along the lower limiting surface of the inclined plane and finally comes to lie, as shown in fig. 2, in the upper section of the recess. During a renewed attraction of the armature the pin slides along the upper limiting surface of the inclined plane, comes into contact with the ratchet lever, swivels the same and detaches the latching of the nose with the fixed point.

The switch slide is thus released and can move upwardly again. As is shown in fig. 3 of FR-AI-2 014 488, the pin finally comes to lie in the step again.

A further object of the present invention is providing an electromechanical remote switch of the kind as explained below in closer detail, in which the movable contact(s) is/are lifted off especially reliably, especially even in cases where they are slightly welded together with the fixed contacts.

SUMMARY OF THE INVENTION With the aforementioned in mind, the present invention provides an electromechanical remote switch, including at least one fixed contact and a movable contact which cooperates with the same and is arranged on a slide and may be displaced by the same relative to the fixed contact, and a magnetic system with an energising coil and an armature which may be displaced by the same and is coupled to the slide, which slide is pressed in the direction towards a first switch position by means of a return spring, with the slide including a cage for holding the at least one movable contact, which cage is formed by two side walls extending in the direction of displacement of the slide and cover plates connecting said side walls, which movable contact, of which there is at least one, is arranged on an approximately rectangular platelet, which platelet is received between the side walls of the cage and is pressed by means of a compression spring against one of the cover plates, which spring is arranged within the cage, wherein the inside surfaces of the cage side walls extend parallel with respect to each other and inclined about an acute angle in an inclined fashion to the direction of displacement of the slide.

In the case of a movement of the slide which leads to a lift-off of a movable contact from the fixed contact to which it is associated, the inside surfaces of the cage side walls slide along the platelets carrying the movable contact and displace the same normal to the direction of displacement of the slide. In this process, the movable contact is displaced laterally relative to the fixed contact, whereby any possible weldings of said two contacts are torn apart.

It has proven to be advantageous that the magnitude of the acute angle is in the range of between 3 and 50 because in this way sufficiently large displacements of the contacts are achieved with respect to the above-mentioned detachment of the contact weldings, but at the same time the easy movement of the relative movements between the slide and the plates carrying the movable contacts is not significantly impaired.

It may be provided for in a further development of the invention that the compression spring is arranged as a helical compression spring which rests with its one end one the platelet and with its other end on one of the cover plates of the cage.

Such springs are functionally reliable standard components which do not require any separate production steps, as a result of which their use keeps low the technical production effort of the remote switch in accordance with the invention. Moreover, sufficient forces can be produced with such helical compression springs for the application in question.

In this connection preferably dome-shaped parts can be provided according to a preferred embodiment of the invention on the platelets and on one of the cover plates of the cage, on which dome-shaped parts are inserted the ends of the compression springs. Any lateral evasion of the spring which can lead up to the impairment of the proper function of the remote switch is thus reliably prevented.

US Pat. No. 5,260,677 relates to a relay, with the magnetic system being shown in a clear representation in fig. 3 of this patent. This figure shows the magnet core as well as the yoke extending parallel to the same, which is designated herein as "field return plate". The clapper is swivellably held on the upper face side of said "field return plate". The "field return plate" comprises "laterally spaced posts" which are designed integrally with the same and project beyond the clapper.

The bistable switching behaviour of the remote switch in accordance with the invention can be converted in a particularly simple manner into a monostable one by omitting the rocker. If both bistable as well as monostabie remote switches are to be produced, all components of both types of product can be produced similarly, i.e. with the same tools and in an especially cost-effective way.

A differentiation between bistable and monostable remote switches during the assembly must be made merely by installing or omitting the rocker.

It may further be necessary to provide an energising coil with another number of windings. Only short voltage impulses are applied to remote-control switches, which is why their coils are arranged with a relatively high rating in order to enable the generation of sufficiently strong magnetic forces with the short voltage impulses for actuating the switch. Energising coils of relays are designed with a lower rating because they are energised for longer periods with voltage.

Despite different numbers of windings, the energising coils can be provided with a similar arrangement concerning their geometrical dimensions, so that all other components of the magnetic system and the other remote switch modules can be provided with a similar arrangement.

According to an especially preferable embodiment of the invention it may be provided that the link is provided with an approximately heart-shaped arrangement.

The bistable contact actuation can be achieved with such an arranged slot in an especially reliable way.

It may be provided for in a further embodiment of the invention that the link is provided with a tip extending in the direction of displacement of the slide, adjacent sections which are arranged in a V-shaped fashion with respect to each other and are separated from each other by an approximately V-shaped arrangement, as well as two curvatures which are adjacent to the straight sections and open into each other in the zone of the V shaped arrangement.

In a link arranged in such a way, the pin can slide without any jamming, which leads to a high functional reliability of the remote switch.

The provision of a rocker in the direction of one of the two wings of the spring pretensioning the slot has proven to be particularly advantageous, because in this way the running track of the pin within the link can thus be reliably predetermined.

In this connection it can be provided that the spring is arranged as a helical compression spring which rests with one end on the inner wall of the lower shell of the remote switch housing and at the other end on the rocker.

Such springs are functionally reliable standard components which do not require any separate production steps, as a result of which their use keeps low the technical production effort of the remote switch in accordance with the invention. Moreover, sufficient forces can be produced with such helical compression springs for the application in question.

In a further development of the invention it may be provided that pin-like shaped parts are provided on the rocker and the lower shell on which the ends of the spring are inserted.

Any lateral evasion of the spring which can lead up to the impairment of the proper function of the remote switch is thus reliably prevented.

It may further be provided that the floor of one of the straight sections of the link is provided with a ramp which commences in the zone adjacent to the curvature, rises in the direction towards the tip and ends with an edge which extends flush to the edge of the V-shaped arrangement portion disposed in the zone of the other straight section.

It is thus ensured that the pin, despite its pretensioning, is unable to run into the straight section of the slot which is provided with this ramp. Instead, it reaches the other straight section of the link. The path of passing through the slot is thus forcibly predetermined, so that the precise shape of the slot is adjusted to this solely possible path of passage and can be applied in an especially low-friction and jamming-free manner.

According to an especially preferably embodiment of the invention it can be provided that the return spring is arranged as a helical compression spring which rests with its first end on a portion of the housing, preferably an intermediate shell, and with its other end on the slide.

Such springs are functionally reliable standard components which do not require any separate production steps, as a result of which their use keeps low the technical production effort of the remote switch in accordance with the invention. Moreover, sufficient forces can be produced with such helical compression springs for the application in question.

In this connection it may be provided that pin-like shaped parts are provided on the rocker and the housing on which the ends of the return spring are inserted.

Any lateral evasion of the spring which can lead up to the impairment of the proper function of the remote switch is thus reliably prevented.

In a further development of the invention it may be provided that the rocker comprises two cylindrical shaped parts which engage in recesses incorporated in the housing of the remote switch, with said recesses having a slightly larger diameter than the shaped parts.

This kind of bearing can be produced in an uncomplicated manner and shows an especially low friction which contributes to the smooth operation of the remote switch.

According to a preferred embodiment of the invention it can be provided that the recesses have a slot-like shape and are incorporated in the face sides of mutually spaced platelets which face the intermediate shell and are shaped on the inner wall of the bottom shell, and that platelets are shaped on the intermediate shell which are spaced from each other, with the plates of the bottom and the intermediate shell being aligned flush with each other when the intermediate shell is placed onto the bottom shell.

In thus arranged recesses the rocker can be inserted in a particularly simple fashion, as a result of which the necessary technical efforts for assembling the remote switch in accordance with the invention can be kept especially low.

DE-AI-37 07 491 describes a clapper relay. The magnetic system comprises an armature acting upon a linearly displaceable actuating bridges.

Said actuating bridges each carry movable switching contacts which are arranged in the form of contact plates and cooperate with fixed switching contacts. The description of DB-AI-37 07 491 describes several times that the two actuating bridges are two mutually separately designed components which are also held displaceably independently from each other.

EP-A2-440 953 deals with a reset lock for a relay. It only shows the armature of the relay as well as the (contact) actuating element which is triggered by said armature and is arranged to be linearly displaceable. Two contact springs are arranged at the end of said actuating element which is averted from the armature, which contact springs carry contact pieces. It is thus provided to arrange the movable contacts of two breaker gaps on a single slide which is common to both breaker gaps. It is not shown that said slide is arranged with a removable arm.

In the embodiments of figs. 3 and 4 the contact springs could be held in cages. A precise statement cannot be made in this respect because the verbal description does not deal in detail therewith; instead, the contact spring bearing is only referred to as an "intermediate member". The drawings, however, show that the side walls of said intermediate members extend in a straight line.

JP-A-59 025 135 describes a multi-pole relay whose armature acts upon a slide via a rocking lever and can displace the same linearly. Said slide comprises four breakthroughs into which small rectangular places are introduced which bear contact pieces at each of their two free ends. The contact plate is pressed against the front face side of the breakthrough by means of a helical compression spring which is also situated within the breakthrough. The lateral limiting surfaces of said breakthrough extend parallel to the direction of displacement of the slide.

It is a further object of the present invention to provide an electromechanical remote switch of the kind explained in closer detail below, which remote switch is characterized by a particularly simple assembling capability. Furthermore, the remote switch to be provided is to be converted especially simply from its principal embodiment comprising two simultaneously actuated breaker gaps into a remote switch comprising only one breaker gap.

The remote switch to be provided comprises two breaker gaps, of which each comprises at least one fixed contact and a movable contact cooperating therewith, with the movable contacts of the two breaker gaps being arranged on a common slide and being movable by the same relative to the fixed contacts. The remote switch further comprises a magnetic system with an energising coil and an armature which may be displaced by said coil and is coupled to the slide, which slide is pressed in the direction towards a first switch position by means of a return spring, with the slide comprising in the zone of the movable contacts two arms which are separated by a slot and each arm carrying at least one movable contact element of a breaker gap each.

In order to achieve the said further object it is provided for in accordance with the invention that at least one section of the first arm, preferably the entire first arm is arranged as a component which is separated from the rest of the slide and can be attached to the remaining part of the slide.

When the remote switch is assembled, this allows inserting the slide at first without the first arm into the bottom shell of the housing and thereafter inserting the intermediate shell which separates the two breaker gaps from each other and which extends through the slot between the two arms. Finally, the first arm can be fixed on the remainder of the slide. This allows omitting the cumbersome threading of the intermediate shell into the slot between the arms, as was previously necessary in the case of the known integral arrangement of the first arm with the remainder of the slide.

Moreover, by simply omitting the first arm and the electrically conducting components of the breaker gap associated with said first arm, it is possible to realize a single-pole remote switch which comprises only one breaker gap. If both two-pole as well as single- pole remote switches are to be produced, all components, and in particular the housing, the magnetic system and the slide of both types of product, can be produced in a similar fashion, i.e. with the same tools and therefore especially cost-effectively. Merely during the assembly is it necessary to make a differentiation between single-pole and two-pole remote switches by the installation of the first arm and the electric components of the first breaker gap.

In a further embodiment of the invention it can be provided that in the first arm which is arranged separately from the remainder of the slide there is incorporated a dovetailed groove with which the first arm can be placed on a corresponding guide means which is shaped on the remainder of the slide.

As a result, the first arm can be fastened to the remainder of the slide in an especially simple and reliable way without any auxiliary materials such as glue.

It is a further object of the present invention to provide an electromechanical remote switch of the kind mentioned below in closer detail whose magnetic system is capable of exerting high forces on the armature in every position of said armature.

The remote switch to be provided comprises at least one fixed contact and a movable contact which cooperates with the same and is arranged on a slide and may be displaced by the same relative to the fixed contact, and a magnetic system with an energising coil and an armature which may be displaced by the same and is coupled to the slide, which slide is pressed in the direction towards a first switch position by means of a return spring, with a magnet core being arranged in the interior of the energising coil which is in a magnetically wellconducting connection with a yoke extending approximately parallel to the longitudinal axis of the coil, with the armature being held pivotably on the face side of said yoke in the zone of its first face side.

In order to achieve the said object it is provided for in accordance with the invention that armature bearing plates are fastened to the side surfaces of the yoke which project beyond the face sides of the yoke and the section of the armature situated there.

Irrespective of the position of the armature, a magnetic flux of a relatively high strength can form through said armature bearing plates, as a result of which relatively high forces can be exerted on the same irrespective of the position of the armature. This leads to a high functional reliability of the magnetic system and thus the entire remote switch.

The invention is now explained in closer detail by reference to the enclosed drawings where especially preferable embodiments are shown, wherein: BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1 and 2 each show an electromagnetic remote switch in accordance with the invention, comprising two breaker gaps with removed upper shell in an oblique sectional view, with one movable contact 2 each being provided for each breaker gap and its connection to a rigid busbar 5 being realized in different ways; Fig. 3 shows a preferred embodiment of an electromagnetic remote switch in accordance with the invention, comprising two breaker gaps with removed upper shell in an oblique sectional view, with two movable contacts 2 being provided for each breaker gap; Fig. 4 shows the magnetic system 8 of a remote switch in accordance with the invention with the slide 7 in an oblique sectional view; Fig. 5 shows the representation of fig. 4, with the rocker 17 being shown in addition; Fig. 6 shows the slide 7 with the rocker 17 in an oblique sectional view; Fig. 7 shows the representation of fig. 3, with the intermediate shell 21 being shown removed from the bottom shell 23 and with the rocker 17 being omitted; Fig. 8 shows the representation of fig. 3, with the slide 7 being located in its second switching position, and Fig. 9 shows an alternative embodiment of the heart-shaped slot incorporated in the slide 7.

DESCRIPTION OF PREFERRED EMBODIMENTS An electromechanical remote switch in accordance with the invention comprises at least one break gap, as in already known such switching devices.

Every break gap comprises at least one fixed contact I and at least one movable contact 2. Said two contacts 1, 2 cooperate in such a way that they allow the making and breaking of an electric circuit which is connected to the same.

As is shown in fig. 1, the fixed contact 1 is fastened to a busbar 3 which opens with its end section 3' into a known connection terminal which is not shown in the enclosed figures. The movable contact 2 is connected via a movable stranded conductor 4 with a further busbar 5 whose end section 5' opens into a second connection terminal which is also not shown. Instead of the stranded conductor 4 it is also possible to provide a busbar 59 which is configured with a low thickness and is therefore elastic (cf. fig. The fixed contacts 2 are each arranged on a slide 7 and are movable by the same relative to the fixed contact 1.

An electric circuit which is to be switched with the remote switch in accordance with the invention can be switched via the said connection terminals. The remote switch in accordance with the invention is provided with a design so as to be installable in a switch cabinet, for which purpose its housing comprises in the known manner a bottom shell 23 and an upper shell which can be placed on the same (not shown in the enclosed drawings).

The remote switch in accordance with the invention is shown as in the enclosed drawings, preferably comprising two break gaps which can be actuated simultaneously by a single slide 7. In order to insulate these two break gaps from each other, the housing further comprises an intermediate shell 21 which is situated between upper and bottom shell 23.

All details described below as inventive can also be applied without any limitations in the configuration of the break gap according to fig. 1 or fig. 2, notwithstanding the fact that they are discussed below on the basis of the preferred embodiment of a break gap as represented in fig.3.

In contrast to the two embodiments above, the break gap of fig. 3 comprises two fixed contacts 1 which are fixed at a small distance from each other and each on a rigid busbar 3, 5. Two movable contacts 2 are provided which are fixed to an electrically conducting platelet, with the distance between said movable contacts 2 corresponding to that of the fixed contacts 1.

The platelet 6 is arranged on a slide 7 in a manner that is explained below in closer detail, as a result of which the slide 7 is also operatively connected with the two movable contacts 2 and can move the same relative to the fixed contacts 1.

A magnetic system 8 is provided for driving the slide 7. In order to also enable the manual actuation of the slide 7, a control button 36 is arranged at its upper end which projects through a breakthrough in the bottom shell 23.

The magnetic system 8 comprises an energising coil 9 and an armature moved by the same. In the embodiment as shown in the enclosed drawings, a magnetic core 11 is arranged in the interior of the energising coil 9 which is in a magnetically well-conducting connection with a yoke 12 extending approximately parallel to the longitudinal axis of the coil. On the face side 61 of said yoke 12, the armature 10, which is arranged as a plane plate, is held pivotably in the zone of its first face side and is therefore arranged as a clapper-type armature (cf. fig.

This bearing is realized in such a way that the armature 10 is placed with an edge of its face side on the face side 61 of the yoke 12. A resilient sheet-metal strip 62 is fastened to yoke 12 which projects beyond the face side 61 of the yoke 12 and comprises a section 63 which is bent in the direction towards the armature and with which it encompasses the armature 10. With said section 63 the resilient sheet-metal strip 62 simultaneously acts as an armature spring.

With the zone of its second face side, the armature 10 projects into a slotshaped recess 13 of the slide 7 and is thus coupled with the slide 7. Slide 7 is displaceably held in the housing of the remote switch in the direction of displacement 14 as symbolized by the arrow and can be moved in said direction of displacement 14 by the armature A special feature of said magnetic system 8 is represented by the armature bearing plates 60 which are fastened to the side surfaces of the yoke 12. They are provided with an arrangement so as to project beyond the face side 61 of the yoke 12 and the section of armature 10 which is.situated in the zone of said face side 61. A relatively large magnetic flux can always flow through said armature bearing plates 60, especially also when the armature 10 is located in its position lifted off from the magnetic coil 11 as shown in figs. 4, 5. As a result, a relatively high magnetic force can always be exerted on the armature 10, which leads to a high functional reliability of the magnetic system 8.

A return spring 20 acts further upon the slide 7 which presses the slide 7 into the first switching position as shown in fig. 3. Said return spring 20 is arranged as a helical compression spring which rests with its first end on a part of the housing, preferably the intermediate shell 21, which separates the two break gaps from each other and whose other end rests on the slide 7. In order to ensure a stable fixing of the return spring 20 on the slide 7 and on the casing (on intermediate shell 21), pin-like shaped parts 22 are provided in the zones of slide 7 and the housing where the ends of the return spring 20 come to rest, into which shaped parts the ends of the return spring 20 are inserted (cf. fig. 7 for the shaped parts 22 which are fastened to the housing, i.e. the intermediate shell 21).

When the energising coil 9 is energised with voltage, a magnetic force is exerted on the armature 10 which is larger than the force produced by the return spring 20, so that the slide 7 can be displaced against the return spring The scope of the present invention and the scope of protection of the enclosed claims also include providing the magnetic system with a different constructional arrangement, e.g. in the form that the armature 10 as can be moved by the energising coil 9 is arranged as a bolt which is held displaceably in the interior of the coil body of the energising coil 9, as is provided for example in striking armature trip elements of circuit breakers.

In a remote switch that comprises the components as discussed up until now, the at least one contact 2 which cooperates with a fixed contact 1 is movable in a monostable fashion because the return spring 20 presses the slide 7 and, with the same, at least one movable contact 2 in the direction towards the first switching position.

In order to provide the remote switch with a bistable switching behaviour, i.e. to provide the same with a bistable contact actuation, a slot 15 is incorporated into the surface of the slide 7. It is preferably provided with a slightly heartshaped arrangement as shown in the enclosed drawings, but can also be provided with a different shape as will be explained below after the explanation of the function of said approximately heart-shaped slot.

A pin 16, which engages in said slot 15, is fixed on a rocker 17. Said rocker 17 is held pivotably in the housing of the remote switch parallel to the slide surface comprising the slot Said bearing is realized by means of two cylindrical shaped parts 18 on the rocker 17 which engage in recesses 19 which are incorporated in the housing.

Fig. 5 shows one of said shaped parts 18. The second lies on the opposite side of rocker 17 which is not visible in fig. 5. The recesses 19 for receiving the cylindrical shaped parts 18 are provided with slightly larger dimensions than the shaped parts 18, as a result of which the rocker 17 can be swivelled also slightly normal to the direction of displacement 14.

The recesses 19 are preferably not configured as fully cylindrical, mutually flush bores which are situated at the distance of the thickness of the rocker 17 because the installation of the rocker 17 in such bores would be difficult. As is shown in fig. 7, the recesses 19 are incorporated in the bottom shell 23 and are provided with a slot-like shape. Preferably, said recesses 19 comprise semicylindrical floors whose diameters are slightly larger than those of the shaped parts 18.

Two platelets 24 are shaped on the inner wall of the bottom shell 23. One such recess 19 is each incorporated in the respective face side of said platelets which faces the intermediate shell 21. The distance between said two platelets 24 corresponds to the thickness of the rocker 17 in the zone of its shaped parts 18. The rocker 17 is used in the distance between the platelets 24, with the shaped parts 18 coming to lie in the recesses 19.

Mutually spaced platelets 24' are also shaped on the intermediate shell 21.

The platelets 24, 24' are arranged in such a way that when the intermediate shell 21 is placed on the bottom shell 23 they extend flush with respect to each other and come to lie with their face sides on top of each other or at an only small distance from other. The recesses 19 of the platelets 24 arranged in the bottom shell 21 are closed off by the platelets 24' of the intermediate shell 23 and the shaped parts 18 are enclosed in the recesses 19.

The heart-shaped slot 15 preferably comprises the unsymmetrical shape as shown in fig. 1 to 8. It comprises a tip 24 extending in the direction of displacement 14 of slide 7 as well as straight sections 25, 29 which are arranged adjacent to said tip 24 (cf. fig. The straight sections 25, 29 are arranged in a V-shaped manner with respect to each other and are separated by a V-shaped arrangement 27. A curvature 26, 28 is adjacent to each of these straight sections 28, which two curvatures 25, 28 open into each other in the zone of the V-shaped arrangement 27.

The heart-shaped slot 15 and the pin 16 which is arranged on the rocker 17 form a locking device which works as follows: In the state of the remote switch as shown in figs. 3, 5 and 6, the pin 16 is located in the tip 24 of the heart-shaped slot 15. The break gap of the remote switch as can be seen in fig. 3 is deactivated because the movable contacts 2 have been lifted off from the fixed contacts 1.

If the energising coil 9 is energised in this situation with voltage, the slide 7 is displaced downwardly (indication of direction relates to the position of the remote switch as shown in fig. During this movement the pin 16 passes at first through tip 24 extending in the direction of displacement 14 and then the righthand straight section 25 of slot 15. The curvature 26 adjacent to said straight section 25 leads the pin 16 via the approximately V-shaped arrangement 27 where it is schematically entered in fig. 6 with the unbroken line.

During said passage of the pin 16 through the slot 15, the rocker is swivelled at first slightly clockwise (until the pin 16 has reached the curvature and then counter-clockwise.

Once the energising coil 9 is de-energised, the return spring 20 can push the slide 7 upwardly. The approximately V-shaped arrangement 27 is displaced in the direction of pin 16 until the same comes to rest on arrangement 27 (cf. position of pin 16 as shown with the dot-dash line). The slide 7 can thus no longer return to the position as shown in fig. 3. Instead, it is held in the position as shown in fig. 8 in which the movable contacts 2 of the break gap as shown in figs. 3, 8 still rest on the fixed contacts 1 and said break gap is thus closed. Said second switching position is thus a (stable) switching position that can also be held when the energising coil 9 is de-energised.

A movement of the slide 7 back to the switching position as shown in fig. 3 can occur by a further voltage impulse applied to the energising coil 9: The slide 7 is moved downwardly again by such a further voltage impulse, as a result of which the pin 16 is moved into the curvature 28 of the left wing of the heartshaped slot 15 (cf. the spotted illustration of the pin 16 in fig. Once the voltage impulse has tapered out, the return spring 20 can move the slide 7 upwardly, with the pin 16 reaching back to the tip 24 of slot 15 via the left straight section 29.

The slide 7 can now be moved back again to the switching position as shown in fig. 3 in which the break gap as shown in fig. 3 is opened.

Departing from the statements made above, the remote switch in accordance with the invention can also be actuated manually, for which purpose the slide 7 (as already explained above) is provided with a control button 36 which projects through the breakthrough in the bottom shell 23. The locking mechanism formed by the pin 16 and the slot 15 works entirely similar in the case of manual actuation.

To ensure that the pin 16 takes the discussed path extending counterclockwise, the following two measures are provided: At first there is a spring which pretensions the rocker 17 in the direction of the left wing of slot 15. The expression awing of slot 15 shall be understood within the scope of this description and the appended claims as the entirety consisting of the straight section 25 or 29 and the adjacent curvature 26 or 28. The pretensioning of the rocker 17 in the direction of the left slot wing shall be understood in an exemplary way. It would be entirely equivalent to pretension the rocker 17 in the direction of the right slot wing. It is obvious that in this case the slot would have to be provided with a design which is mirrored about an axis extending in the direction of displacement 14.

Said spring 30 is arranged in the preferred embodiment of the enclosed drawings as a helical compression spring which rests at the one end on the inner wall of the bottom shell 23 and at the other end on the rocker 17. For the purpose of stably fixing the spring 30 it is possible to provide in analogy to the return spring 20 pin-like shaped parts 37 both on the rocker 17 as well as on the bottom shell 23 on which the ends of the spring 30 are placed.

The force exerted by said spring 30 on the rocker 17 ensures that the pin 16 is always pressed in the direction towards the left wing of slot 15 and thus assumes the positions as shown with the unbroken, dot-dash and dotted lines.

One could also omit said spring 30 if its function (pressing rocker 17 in the direction towards the left wing of slot 15) is achieved otherwise. This can occur in such a way for example that the rocker 17 is configured inclined in a slightly oblique way in the direction towards the left slot wing, as a result of which the end of rocker 17 which is provided with the pin 16 is pressed in the direction towards the left wing of the slot by means of gravity.

In order to prevent that the pin 16 enters the left-hand straight section 29 after leaving the tip 24, the floor of said straight section 29 is provided with a ramp 31 which commences in the zone adjacent to the curvature 28 and rises in the direction towards the tip 24. The ramp 31 ends with an edge 33 which extends flush to the edge 32 of the V-shaped arrangement 27, which edge is situated in the zone of the straight section 25. The base-side end of pin 16 slides along said edge 33 when leaving the tip 24 and is thus not able to enter the left-hand straight section 29, but is forced to run along the edge 32 of the V-shaped arrangement 27 into the right-hand straight section When the rocker 17 is pretensioned in the direction towards the right wing of the slot 15, the ramp 31 which was discussed above must be arranged in the right-hand straight section 25 of the slot A similarly possible alternative constructional arrangement of the heartshaped slot 15 is to provide the same with a completely symmetrical arrangement, i.e. with identical left and right wings (cf. fig. After leaving tip 24, the pin 16 comes into contact with the blade 34 of the V-shaped set-off 27 and is then deflected at random into the right straight section 25 or the left straight section 29. Once the pin 16 was deflected by the curvature 26 or 28, it comes to lie in the position shown in the dot-dash line below the blade 35 after the voltage impulse as applied to the energising coil 9 has tapered out. In the case of a renewed displacement of the slide 7 the pin 16 comes into contact with said blade and is guided at random into the right curvature 26 or the left curvature 28. In both cases the pin 16 finally returns to the tip 24.

It is clear from the explanations of the functions of slot 15 that the same can also be provided with a shape that departs from the shape of a heart to the extent that in such a shape the pin is held in a stable fashion in two mutually spaced latching hold points and the slot 15 is able to guide the pin 16 in a displaceable manner at low friction between said two latching hold points. Based on the embodiment according to fig. 9 it would be possible for example to provide the slot 15 with the shape of half a heart, i.e. it would comprise only one of the two wings.

According to another possible embodiment, the shape of this wing could depart from the shape of half a heart and be arranged in the form of half an ellipse for example.

The invention is thus not limited to the approximately heart-shaped design of the slot 15 which is shown in the drawings.

The remote switch in accordance with the invention can be provided with an arrangement so as to comprise any desired number of breaker gaps, whereby the enclosed drawings show a remote switch comprising merely two breaker gaps. Figs. 1 to 3 merely show one breaker gap which is arranged in the zone between the intermediate shell 21 and the upper shell of the remote switch housing. The second breaker gap is situated between the intermediate shell 21 and the bottom shell 23 and is arranged with respect to the constructional principle like the first breaker gap as shown in figs. 1 to 3.

It may be provided that said second breaker gap is arranged with a switching function that differs from the first breaker gap. It means that when the first breaker gap has a make-contact function (the breaker gap is opened in the first switching position as shown in figs. 1 to 3; it is closed in the second switching position as shown in fig. the second breaker gap is provided with a breakcontact function, so that it is closed in the first switching position (fig. 1 to but opened in the second switching position (fig. 8).

The functions of the two breaker gaps can be chosen at will or can be combined at will. For example, both breaker gaps can be arranged as make contacts or both as break contacts or one each or both breaker gaps can be arranged as changeover contacts.

Magnetic system 8 and slide 7 are provided for both breaker gaps jointly, i.e. the movable contacts 2 of the two breaker gaps are arranged on a single common slide 7 and are movable by the same relative to the fixed contacts 1.

As is shown most clearly from fig. 4, slide 7 comprises in the zone of the movable contacts 2 two arms 41, 42 which are separated by a slot 40. The movable contact elements 2 of the remote switch are arranged on said two arms 41, 42, with each arm 41, 42 carrying the only movable contact element 2 or both movable contact elements 2 of a breaker gap each. When the housing of the remote switch is completely compiled, the wall 45 of the intermediate shell 21 is disposed in the zone of the slot 40. Each of the two arms 41, 42 thus projects into the respectively associated breaker gap and is separated in the zone of the movable contact 2 from the other breaker gap by the wall 45 of the intermediate shell 21.

A particularity of the slide 7 as provided in a remote switch in accordance with the invention is that the entire first arm 41 is arranged as a component which is separated from the remainder of slide 7, but can be fixed to the remainder of slide 7. This fixability can principally be realized at will, e.g. the arm 41 could be glued to the remainder of slide 7..

According to the preferred embodiment as shown in the enclosed drawings, a detachable fixing of the arm 41 in the form of a positive fit on the slide 7 is provided.

A dovetailed groove 43 is thus incorporated in the first arm 41. In the zone of the remainder of the slide 7 in which the arm 41 is to be fixed a guide means 44 is shaped which with respect to its cross-sectional shape corresponds to that of the groove 43 and is provided with a slightly smaller design than the same.

The arm 41 can be placed on said guide means 44 and can thus be fixed in a positive-locked way on the remainder of the slide 7.

The shape of the cross section of groove 43 and guide means 44 can be chosen at will and can be the shape of a hammer as shown in the drawings.

Alternatively, the groove 43 and the guide means 44 could have a trapezoid cross section, whereby the longer side edge of the mutually parallel extending side edges of said trapeze must be situated in the region of the floor of the groove 43 or the thus corresponding surface of the shaped part 44 in order to achieve a positive-locking connection between arm 41 and the remainder of the slide 7.

As is shown in fig. 7, the slide 7 can be placed into the bottom shell 23 during the assembly of the remote switch. Then the intermediate shell 21 can be inserted and finally the arm 41 can be inserted on the remainder of the slide 7.

The cumbersome threading of the slide arms 41 and 42 into the zones between bottom shell 23 and the intermediate shell 21 or between upper shell and intermediate shell 21 can thus be avoided.

In order to achieve this easy mountability of the slide 7 in the remote switch housing, it may be provided, by departing from the illustration above, that not the entire arm 41 but merely one section of the arm 41 (namely the lower section which carries the movable contact 2) is arranged as a component which is separate from the remainder of the slide 7. The other section 41 is arranged integrally with the slide 7. Notice should be taken however that the other arm section which is arranged integrally with the slide 7 still ends above the wall when the slide 7 is in the first switching position (fig. so that during the assembly of the remote switch the wall 45 of the intermediate shell 21 does not have to be threaded into the slot 40 between the two arms 41, 42.

A further aspect in accordance with the invention is the constructional arrangement of the fixing device of the movable contacts 2 on the slide 7. As is shown in fig. 6, the slide 7 comprises a cage 50 for fixing the movable contacts 2 of a breaker gap. Since the remote switch as shown in the drawings comprises two breaker gaps whose movable contacts 2, as described above, are arranged on two arms 41, 42, each of said arms 41, 42 is equipped with such a cage Said cage 50 comprises two side walls 51, 52 which extend in the direction of displacement 14 of the slide 7 as well as cover plates 53, 54 which connect the same. The one movable contact 2 (cf. fig. 1,2) or the two movable contacts 2 (cf.

fig. 3) is/are arranged on an approximately rectangular platelet 6, which platelet 6 is received between the side walls 51, 52 of the cage 50. A compression spring is arranged within the cage 50, which spring presses the platelet 6 against one of the cover surfaces 53, 54.

The question as to which of the two cover surfaces 53, 54 the platelet is pressed against depends on the switching function (make contact or break contact) that the respective breaker gap is to fulfil. If the breaker gap is arranged (as in fig. 3) as a make contact, with the fixed contacts 1 being arranged below the lower cover surface 54, the platelet 6 is pressed against the lower cover surface 54. In the case of a movement of slide 7 which leads to the closing of said breaker gap, the movable contacts 2 come to rest on the fixed contacts 1.

As a result of this contact, platelet 6 can no longer be displaced any further in the case of a further progressing displacement of slide 7. Instead, the compression spring 55 is compressed. The compression pressure with which the movable contacts 2 are pressed against the fixed contacts 1 is increased by the compression of the compression spring When arranging the breaker gap as a break contact, the fixed contacts 1 rest above the upper cover surface 53 of the cage 50, which is why the platelet 6 is pressed against said upper cover surface 53 (cf. the first arm 41 situated at the left-hand side in fig. 6).

The compression spring 55 is preferably arranged as a helical compression spring which rests with its one end on platelet 6 and with its other end on one of the cover plates 53, 54 of cage 50. Alternatively, the compression spring 55 could be arranged as a leaf spring for example.

When arranging the compression spring 55 as a helical compression spring, shaped parts 56 are arranged on platelet 6 and on one of the cover plates 53, 54 of cage 50 according to the preferred embodiment of the remote switch as shown in the drawings, on which shaped parts the ends of the compression spring 55 are inserted. Said shaped parts 56 preferably are provided with a dome-shaped arrangement. They could also be provided as cylindrical pins, however.

The inside surfaces 57, 58 of the cage side walls 51, 52 extend parallel with respect to each other and inclined by an acute angle a to the direction of displacement 14 of slide 7. The magnitude of said acute angle a is preferably in the range of between 30 and As already explained above, when the movable contacts 2 rest on the associated fixed contacts 1 the platelet 6 carrying said movable contacts 2 is lifted off from the cover surface 53, 54 of cage 50 on which it may come to rest and the compression spring 55 is compressed accordingly.

During a displacement of the slide 7 which leads to a lift-off of the movable contacts 2 from the associated fixed contacts 1, the movable contacts 2 are not lifted off from the fixed contacts 1 for the time being: The platelet 6, and with the same the movable contacts 2, are pressed by the compression spring 55 against the fixed contacts 1. The compression spring 55 is relaxed during the progressing displacement of the slide 7. Only when one of the cover plates 53, 54 of the cage 50 comes to rest on the platelet 6, the same is displaced and the movable contacts 2 will be lifted off from the fixed contacts 1.

During the displacement of cage 50 relative to platelet 6 which occurs prior to said lifting off, the inside surfaces 57, 58 of the cage side walls 51, 52 slide along the platelet 6. As a result of the inclination of the inside surfaces 57, 58 relative to the direction of displacement 14 of slide 7, the platelet 6 is displaced normally to the direction of displacement 14. The movable contacts 2 are thus displaced parallel to the surfaces with which they rest on the fixed contacts 1. In the case of this lateral relative movement of the movable contacts 2 relative to the fixed contacts 1, which relative movement occurs normally to the direction of displacement 14 or the lifting movement, slight weldings between the contacts 1, 2 are torn open.

In the case of the displacement of the slide 7 which leads to an application of the movable contacts 2 on the associated fixed contacts 1, the movable contacts 2 are placed on the fixed contacts 1 at first (as already explained above) and in the case of a further progressing displacement 7 of the slide 7 the compression spring 55 acting upon the platelet 6 is compressed. During this compression too the inside surfaces 57, 58 slide along the platelet 6, which produces a displacement of the movable contacts 2 extending normally to the direction of displacement 14. Since the movable contacts 2 already rest on the fixed contacts 1, the movable contacts 2 are rubbed on the fixed contacts 1, which leads to a cleaning of the contact surfaces of both contacts 1, 2. This contributes to achieving a low contact resistance and to maintaining this low resistance value over the service life of the remote switch.

Claims (4)

1. An electromechanical remote switch, including at least one fixed contact and a movable contact which cooperates with the same and is arranged on a slide and may be displaced by the same relative to the fixed contact, and a magnetic system with an energising coil and an armature which may be displaced by the same and is coupled to the slide, which slide is pressed in the direction towards a first switch position by means of a return spring, with the slide including a cage for holding the at least one movable contact, which cage is formed by two side walls extending in the direction of displacement of the slide and cover plates connecting said side walls, which movable contact, of which there is at least one, is arranged on an approximately rectangular platelet, which platelet is received between the side walls of the cage and is pressed by means of a compression spring against one of the cover plates, which spring is arranged within the cage, wherein the inside surfaces of the cage side walls extend parallel with respect to each other and inclined about an acute angle in an inclined fashion to the direction of displacement of the slide

2. An electromechanical remote switch as claimed in claim 1, wherein the magnitude of the acute angle is in the range of between 3 and 50

3. An electromechanical remote switch as claimed in claim 1 or 2, wherein the compression spring is arranged as a helical compression spring which rests with its one end on the platelet and with its other end on one of the cover plates of the cage.

4. An electromechanical remote switch as claimed in claim 3, wherein preferably dome-like shaped parts which are arranged on the platelet and on one of the cover plates of the cage and on which the ends of the compression spring are inserted. An electromechanical remote switch according to claim 1, substantially as hereinbefore described with reference to the accompanying drawings. DATED this 13th day of September 2004 MOELLER GEBAUDEAUTOMATION KG WATERMARK PATENT TRADE MARK ATTORNEYS GPO BOX 2512 PERTH WA 6001 AUSTRALIA P22063AU02