Electrical switch

Abstract

An electrical switch comprising a drive mechanism for moving a switch component at a pre-selected variable speed. A movable additional mass is connected at a drive branched-off the drive mechanism of the moved switch component, said branch drive possessing a transmission ratio which is variable as a function of the position of the moved switch component.BACKGROUND OF THE INVENTIONThe present invention relates to a new and improved construction of an electrical or electric switch having a drive mechanism for moving a switch component at a speed which varies in a pre-selected manner.For instance when separating the contacts of certain switches it can be necessary to displace the moved contact, i.e. the moved switch component at a variable speed in order to take into account the different requirements regarding the cut-off or separation operation e.g. the extinguishing of the arc and the gentle slowing down during as rapid as possible switching operation. In order to be able to cope with the foregoing there have already been used drives (for instance Maltese cross drives or elliptical gear drives) possessing a transmission ratio which varies depending upon the relative position of the drive and the moved switch component. In order to reduce the possibly arising surges, there have been provided balancing oscillating masses in the transmission chain of the drive between the power source and the moved switch component. However, increased drive power is necessary due to the friction and mass of such drives. On the other hand, there are in direct conflict with one another the demands regarding smooth transition and the high power requirements.SUMMARY OF THE INVENTIONHence, it is a primary object of the present invention to provide an improved construction of an electrical switch which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.Another and more specific object of the present invention aims at the provision of a new and improved construction of switch having a drive which, with relatively small drive power and as simple as possible construction, renders possible the realization of a predetermined course of the speed of the moved switch component.Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the invention contemplates the provision of a new and improved construction of an electrical switch of the previously mentioned type which is manifested by the features that a movable additional mass is connected to a drive branched-off from the positive drive mechanism of the moved switch component, this branched-off drive or branch drive possessing a transmission ratio which is variable as a function of the position of the moved switch component.The fact that the additional mass is connected via the aforementioned branch drive possessing variable transmission ratio renders it possible for the inertia of the additional mass, depending upon the transmission ratio of the drive, to have a different effect at different points in time of the switching operation and different amounts of drive energy are tapped-off of the drive mechanism of the moved switch component and absorbed or again returned back to the system, so that there can be realized an almost random variation of the course of the speed of the moved switch component.Now since it is possible to construct the moved switch component and its direct drive as simple and mass-free as possible, it is possible to maintain small the drive power. However, it is possible to select the additional mass to be relatively large, so that the same can develop a different degree of action depending upon the transmission ratio of the branched-off or branch drive. If the momentary transmission ratio of the branch drive is adjusted such that the additional mass does not or hardly moves, then the drive energy acts completely upon the moved switch component and markedly accelerates the same. However, if the transmission ratio is altered such that the additional mass must be moved more rapidly, then such is initially braked owing to the inertia of the entire drive whereupon it tends to again store energy as an oscillating mass, if after reaching equilibrium the drive power (e.g. in the case of a power or energy storage) again decreases. Also in this stage it is possible to influence the effect of the additional mass upon the moved switch component by changing the transmission ratio.There can be connected at least one further movable additional mass after the additional mass by means of at least one further drive possessing a variable transmission ratio. This results in further influencing the course of movement and thus the course of the speed of the moved switch component without requiring complicated drives.In accordance with a simple constructional embodiment of the invention there can be used as the branched-off or branch drive lever drives, for instance such where it is possible to change the lever arm ratio or leverage during the course of the rocking or pivoting of the lever in such a manner that the lever engages into a slot of a rotatable cam disk. The cam disk can be part of an additional mass.As the power or energy source of the drive there can be used all known systems, such as springs, hydraulic devices, pneumatic devices, motors, and so forth, just to mention a few noteworthy possibilities.

Description

Claims

1. An electrical switch including a switch component, a drive mechanism for positively moving the switch component at a speed which can be varied in a pre-selected manner, branch drive means branched-off from said drive mechanism of the moved switched component, a movable additional mass connected with said branch drive means, said branch drive means possessing a transmission ratio which is variable as a function of the position of the moved switch component.

2. The electrical switch as defined in claim 1, wherein at least one further additional mass is connected via a further branch drive means possessing a variable transmission ratio following said additional mass.

3. The electrical switch as defined in claim 1, wherein the additional mass is connected with a counterweight.

4. The electrical switch as defined in claim 1, wherein the additional mass is connected with a compensation weight.

5. The electrical switch as defined in claim 2, further including a counterweight with which there is connected at least one of the additional masses.

6. The electrical switch as defined in claim 2, further including a compensation weight with which there is connected at least one of the additional masses.

7. The electrical switch is defined in claim 2, wherein at least one of the branch drive means of one of the additional masses comprises a lever drive structure incorporating an element engaging in a slot of a cam disk.

8. The electrical switch as defined in claim 7, further including means mounting the cam disk to be rotatable about a center of rotation, and said slot is arranged essentially radially with respect to the center of rotation of the cam disk.

9. The electrical switch as defined in claim 7, further including means mounting the cam disk to be rotatable about a center of rotation, said slot at least extending in stages in a direction which extends past the center of the rotation of the cam disk.