DK2242073T3

DK2242073T3 - The control mechanism for an electric switch

Info

Publication number: DK2242073T3
Application number: DK10153765T
Authority: DK
Inventors: Vesa Ekström
Original assignee: Strömfors Electric Oy
Priority date: 2009-04-16
Filing date: 2010-02-17
Publication date: 2015-03-02
Also published as: EP2242073A3; FI20095414A0; EP2242073A2; FI121099B; EP2242073B1

Description

Description direction, but is only connected by its ends between the rocker arm and the control element. This hampers the [0001] The invention relates to an electrical switch con- process of assembling a control mechanism and an elec- trol mechanism as set forth in the preamble of claim 1. trical switch. In addition, the assembly has a poor relia- [0002] Previously known are various electrical switch bility as the coil spring may slip off of its position between control mechanisms, including a rocker arm and a control the rocker arm and the control element, whereby the con- element operated thereby. The control element is actu- trol mechanism develops a fault and no longer functions ated by means of the rocker arm between two opposite as intended. transition positions, i.e. first and second transition posi- The document FR2220859 discloses an electrical switch tions, at least one of said positions being adapted to en- according to the preamble of claim 1. able a passage of electric current through the control [0005] It is an object of the invention to eliminate the element. The control element is biased by a spring, such drawbacks associated with prior known switch mecha- that the control element is pressed by the spring to the nisms. Another object of the invention is to provide a new first or second transition position as the rocker arm is switch mechanism, which is simple in design, easy to pivoted over to the first or second side of a mid-position, assemble, and reliable. respectively. Such control mechanisms have been dis- [0006] A switch mechanism according to the invention closed e.g. in International patent application publication is characterized by what is presented in claim 1. Preferred WO 2008/155499 and in Canadian patent publication CA embodiments of the invention are presented in the de- 976589. pendent claims.

[0003] In the cited International patent application pub- [0007] The electrical switch control mechanism ac- lication WO 2008/155499, the control mechanism has its cording to the invention comprises a rocker arm and a spring disposed for contact with a boss of the rocker arm. control element, which is movable between two transition A drawback in this configuration is the fact that the spring positions, first and second transition positions, by means must be relatively stiff and must be propped from outside of the rocker arm, the electric current being adaptable to in a suitable cylindrical recess of the boss in order to pass through the control element from one contact ter- avoid buckling incidents, yet the propping must be im- minal to the other at least in one of the transition positions, plemented in such a way that one end of the spring, which said rocker arm and control element having in association is intended for attachment to the control element, shall therewith a spring, specifically a coil spring, which is set be clear of the boss by an appropriate distance and un- between the rocker arm and the control element, such attached for a partial contraction as the control element that the control element is pressed by the spring either is switched to another position. Another drawback is that to the first or the second transition position as the rocker such a structure is relatively complicated to manufacture, arm is pivoted with respect to a mid-position and a pivot and assembling the control mechanism with an electrical axis over to the first or second side, respectively. Accord- switch is a laborious undertaking. A still further drawback ing to the invention, the control element comprises a shaft is the fact that the control mechanism develops quite a with its first end set pivotably in connection with the first considerable height as the spring needs to be relatively contact terminal and with its second end unattached and long. In addition, the spring must be laterally rigid and, pointed towards the rocker arm and provided with at least hence, made from a heavy-duty material. one contact pin, and that between the control element’s [0004] In the cited Canadian patent publication CA ends, around the shaft, is provided a coil spring and in 976589, the control element of a control mechanism is a association with the shaft and the coil spring is further flat component featuring two parallel straight lateral seg- arranged a connecting piece provided with holders in a ments and having a tapering tip portion pointing in a di- way to enable its movement along the shaft and, at the rection opposite to that of the lateral segments. By means same time, the coil spring is allowed to compress at least of pivot brackets, pivotably disposed on the opposite out- partially and respectively to expand along the shaft, and er edges of the lateral segments, the control element is that the rocker arm comprises two parallel bosses, the bearing-mounted on two parallel spaced-apartsegments ends of which are fitted in the holders of the connecting of a first guide plate of the housing. The control element piece, the control element having its shaft adapted to is biased by a coil spring, which is disposed between the travel in a gap between the parallel bosses. rocker arm’s boss and a trunnion present between the [0008] The invention provides a benefit of simple decontrol element’s lateral segments. A drawback in this sign and convenient manufacturing. The switch mecha- assembly is that the control element’s tip portion, which nism’s control element only comprises three parts, which is provided with contact pins, is disposed on that side of in a manufacturing process are assembled in a straight- the control element’s bearing axle which is opposite with forward manner with each other and additionally in con- respect to the rocker arm, whereby the control mecha- nection with a rocker arm. nism becomes a relatively tall structure. As a result, the [0009] Another benefit of the invention is the possibility control mechanism cannot be accommodated in a shal- of providing a control mechanism and an electrical switch low housing, nor in an outlet box. Another drawback is applying the same in the form of a low profile component that the coil spring is not supported on anything in a lateral and further in such a way that the rocker arm’s pivot angle is relatively small. The control mechanism’s low profile the control element 3, such that the control element 3 is

and the rocker arm’s small pivot angle can be used for a pressed by the spring 8 either to the first A or second B beneficial effect on the appearance of an electrical transition position in response to pivoting the rocker arm switch. In addition, a flat electrical switch is preferred from 2 relative to a mid-position or a plane C-C, which in this the standpoint of electrical installations for not requiring example coincides with the vertical plane, and, respec- e.g. a major installation depth. tively, over to a first or second side with respect to a pivot [0010] The invention will now be described in morede- axis D-D extending thereby. tailwithreferencetotheaccompanyingdrawing, inwhich [0016] One or more control mechanisms 1 is accommodated in the housing 4 and constructed foran electrical fig. 1 shows a control mechanism of the invention in switch provided with one or more rockers. Each control detail from the front in a first transition position; mechanism 1 includes conductors 6; 61, 62, 63 set in connection with the housing 4 and used for connecting fig. 2 shows a control mechanism in detail from the the contact terminals 5; 51,52, 53 to matching terminals front in a second transition position; 7; 71,72, 73, by which the control mechanisms are con nected to external electrical wiring. The housing 4 is con-fig. 3 shows a control mechanism from the side in a structed from a highly dielectric material, such as an ap- condition dismantled for assemblage parts; and propriate type of plastic. The conductors 6 and the ter minals 5, 7 are made of an electrically highly conductive fig. 4 shows a similar control mechanism from the side material such as copper. in an assembled condition. [0017] In the process of electrical installation, the elec trical switch is fitted e.g. in an outlet box and connected [0011] Like reference numerals in the figures are used as part of the electricity network within a building or the for like parts. like.

[0012] One preferred electrical switch control mecha- [0018] The electrical switch is connected between the nism, intended for attachment in an appropriate outlet electricity network and a current-using appliance, such box, is detailed in the drawings. as a lighting fixture, in such a way that the electrical switch [0013] An electrical switch control mechanism 1 com- enables connecting the current-using appliance to the prises a rocker arm 2 and a control element 3 operated electricity network for commencing the power supply to thereby. The rocker arm 2 and the control element 3 are the current-using appliance and, respectively, switching set in a suitable electrical switch housing 4. The control off the connection with the electricity network and termi- element 3 is accommodated in a housing cavity 41, with nating the power supply to the current-using appliance, contactterminals 5; 51,52,53 also conveniently provided [0019] The control element 3 of the electrical switch therein. The control element 3 is actuated by means of control mechanism 1 comprises a shaft 31 and a coil the rocker arm 2 between two transition positions, i.e. spring 8. The shaft 31 is constructed in an electrically between a first A and a second B transition position, highly conductive material, such as copper. A first end which are detailed in figs. 1 and 2. The control element 311 of the shaft 31 is set pivotably in connection with the 3 is adapted to electrically couple the first and second first contact terminal 51. Most preferably, this is imple- contact terminals 5; 51, 52 of an electrical switch with mented in such a way that the first contact terminal 51 is each other in the first transition position A and, respec- provided with a slot 511, the shaft 31 having its first end tively, the first and third contact terminals 5; 51,53 of an 311 fitted therein. Being pressed by the spring 8, the electrical switch with each other in the second transition shaft’s first end 311 holds its position well in the slot 511 position B. Thereby, the electric current is adaptable to and is not able to move linearly in a shaft pivoting plane travel through the control element 3 either in the first A in the contact terminal 51 as the control element has its or second B transition position. transition position changed from the first A to the second [0014] It should be noted that, in the simplest embod- B or vice versa. iment of a control mechanism according to the invention, [0020] A second end 312 of the shaft 31 is unattached the control element 3 is adapted to couple electrically the and pointed towards the rocker arm 2. In addition, the firstand second contactterminals5; 51,52ofan electrical shaft 31 has its second end 312 provided with at least switch with each other in the first transition position A, one contact pin, in this embodiment with two, a first and while no coupling occurs in the second transition position a second contact pin 32, 33, present on various sides of B. The third contact terminal 5; 53 is not absolutely nec- the shaft. In a preferred embodiment of the invention, the essary in this case. Thus, in the first A transition position, shaft 31 is an elongated, preferably flat, straight bar. the electric current is adaptable to travel through the con- [0021] Between the ends 311, 312 of the control ele- trol element 3, and in the second transition position B the ment 3, around the shaft 31, is disposed a coil spring 8. electric current is disconnectable. In connection with the shaft 3, and thus in connection [0015] In association with the rocker arm 2 and the with the spring 8, is further disposed a connecting piece control element 3 is a spring 8, particularly a coil spring. 9 provided with holders 91, 92. This connecting piece 9

The spring 7 is disposed between the rocker arm 2 and is most preferably provided with a hole, the shaft 31 being adapted to extend therethrough. The connecting piece 9 such as troughs, of the connecting piece 9. The rocker is able to move along the shaft 31 and, at the same time, arm 2, along with its brackets 21,22, is pressed towards the coil spring 8 is able to compress at least partially and, the bottom of the cavity 41 and the first contact terminal respectively, to expand along the shaft. In a preferred 51, the coil spring 8 being compressed to some extent embodiment of the invention, the shaft 31, preferably its by the action of the connecting piece 9 and, at the same first end 311, is provided with an abutment 34, in this time, the shaft 31 pivots either to the first or second tran- case an expansion 34a, against which a second end 82 sition position A, B. Now, the rocker arm 2 is locked to of the coil spring 8 is adapted to rest, while the connecting the housing by means of a suitable trunnion 24, said trun- piece 9 is adapted to act on a first end 81 of the coil spring nion being adapted to extend along the pivoting axis D- 8. D of the rocker arm 2. The control mechanism is basically [0022] The rocker arm 2 comprises a flat lever member ready for operation. 20 and two parallel brackets 21,22, which are set at an [0026] Presuming that the control mechanism has its angle against the lever member and on the side opposite control element 3 and, respectively, its rocker arm 2 in to its external surface. The ends of the brackets 21,22 the transition position A (see fig. 1).Thus, in this position, are fitted in the holders 91,92 of the connecting piece 9. by applying a pressure on the first half 20a, the rocker

Thus, the shaft 31 of the control element 3, especially arm 2 has been pivoted over a small angle a with respect the shaft’s second end 312, is located in and able to move to the vertical plane C-C extending byway of the trunnion in a gap 23 between the parallel brackets 21, 22. The 24 and the pivoting axis D-D, the consequence of this rocker arm 2 is constructed from a highly dielectric ma- having been that the second or unattached end 312 of terial, such as a suitable type of plastic. the shaft 31 and a first contact pin 32 are resting against [0023] In a preferred embodiment of the invention, the the second contact terminal 52. When it is desirable to connecting piece 9 present on the shaft 31 is a substan- shift the control element 3, and respectively the rocker tially U-shaped component. The connecting piece 9 is arm 2, to the transition position B, a pressure is applied disposed on the shaft 31 in such a way that the U-shaped to a second half 20b of the rocker arm 2 across a labile component opens up towards the first end 311 of the mid-position, whereby it pivots, together with the control shaft 31, the spring 8 being fitted inside this component. element 3, in the opposite direction over a small angle a

The connecting piece 9 has its ends, and at the same relative to the vertical plane C-C, and at the same time, time, the U-shape has its tips provided with holders 91, by means of the connecting piece 9 and the spring 8, the 92 for the rocker arm’s 2 brackets 21,22. In a preferred shaft 31 of the control element 3 and a second contact embodiment of the invention, the holders 91,92 are chan- pin 33 present at its second end 312 pivot, in the vertical nel-shaped members or troughs. The troughs open up plane and in a plane orthogonal to the pivoting axis, over towards the rocker arm 2. In the process of assembling to the other side or to the second transition position B, thecontrol mechanism, the unattached endsoftherocker wherein the second or unattached end312 of the shaft arm’s 2 brackets 21, 22 are fitted in the holders 91,92, 31 and the second contact pin 33 are resting against the and in this case in the troughs of the connecting piece 9. third contact terminal (see fig. 2). Respectively, by press-

The tips of the rocker arm’s 2 brackets 21,22 are pref- ing the first half 20a of the rocker arm 2 across the labile erably wedge-shaped, thus fitting well in the trough- mid-position, the control element 3 is enabled to pivot shaped holders. back to the first transition position A.

[0024] The connecting piece is most preferably a U- [0027] The invention is not limited to only cover the shaped strip of metal, having its unattached ends, and foregoing exemplary embodiment, but a multitude of consequently the tips of the U-shape’s arms, provided modifications are plausible as long as keeping within an with holders 91,92, i.e. designed as troughs. inventive concept as defined in the claims.

[0025] The control mechanism 1 according to the invention is most preferably assembled, such that the control element 3 first has its shaft 31 fitted with the coil spring 8 in a way of having its first end 81 resting against the abutment 34, i.e. in this case against the expansion 34a of the shaft. This is followed by threading the connecting piece 9 by way of the hole onto the shaft 31 against the second end 82 of the coil spring 8. The shaft 31, including the coil spring 8 and the connecting piece 9, is fitted in the cavity 41 of the housing 4, reserved for the control mechanism 1, such that the shaft 31 has its second end 312 resting in the slot 511 of an electrical switch’s first contact terminal 51. The shaft 31 has its second end 312, which is unattached, fitted between the rocker arm’s 2 parallel brackets 21, 22, preferably within a gap, such that the brackets’ tips 21 a, 22a find the holders 91,92,

Claims

An electric switch control mechanism (1) comprising a rocker arm (2) and a control element (3) movable between two transition positions, a first transition position (A) and a second transition position (B), by the rocker arm, the electric current being caused to pass through the control element from one contact terminal (5; 51, 52, 53) to the other, at least in one of the transition positions, the rocker arm (2) and the control element (3) adjacent thereto having a spring (8), specifically a helical spring which is disposed between the rocker arm and the control member such that the control member is pressed by the spring to either the first (A) or second (B) transition position when the rocker arm is tilted relative to a center position and a rocker axis ( DD) over to the first, respectively. a second side, characterized in that the control element (3) comprises a shaft (31) which is pivotally connected with its first end (311) in connection with the first contact terminal (5) and with its second end (312) not pointing and pointing against the rocker arm (2) and provided with at least one contact pin (32, 33) and between the ends of the control element (311, 312), around the shaft (31), a helical spring (8) is provided and adjacent the shaft and the coil spring is further provided with a connecting piece (9) which is provided with holders (91, 92) in a way to enable its movement along the shaft and, at the same time, the coil spring is allowed to be compressed at least partially or respectively. expanding along the shaft, and the rocker arm (2) comprises two parallel projections (21, 22), the ends of which are arranged in the holders (91, 92) of the connector (9), the guide member having its shaft (31) arranged to move say in a gap between the parallel projections.

Control mechanism for an electrical switch according to claim 1, characterized in that, adjacent to the first contact terminal (51) is a slot (511), the shaft having its first end (311) disposed therein.

Control mechanism for an electric switch according to claim 1 or 2, characterized in that the shaft (31) is an elongated, straight rod which is also most preferably flat.

Control mechanism for an electric switch according to claim 1, 2 or 3, characterized in that the shaft (31), preferably at its first end (311), is provided with a device (34), such as an extension of the shaft, against which the screw spring (8) has its other end arranged to rest, while the connector (9) is provided at a first end of the screw spring.

Control mechanism for an electrical switch according to any one of the preceding claims, characterized in that the connector (9) is a substantially U-shaped component having its non-connected ends, and at the same time the tips of a U-shape, provided with holders (91.92) for the projections (21.22) on the rocker arm (2).

Control mechanism for an electric switch according to claim 5, characterized in that the holders (91, 92) are recesses.

Control mechanism for an electric switch according to claim 5 or 6, characterized in that the connection piece (9) is made of a metal strip.