Title of Invention

"VACUUM SWITCH"

Abstract

The invention relates to a vacuum switch for railroad operation with at least two switching contacts and a drive system with a switch rod moving at least one switching contact. The reliability of the vacuum switch is to be improved in order to permit secure switching on even at low temperatures or weak battery voltage and to ensure secure locking in a switching position. To this end, it is provided for the drive system to further comprise a main spring transferring the switch rod from an open position into a switching position, a drive for preloading the main spring, a locking mechanism for locking the main spring in the preloaded condition, and a pivoted latch, the latch being arranged so as to be longitudinally shifted at least in a position locked against pivoting, such that the switch rod can be released by means of the latch during the transfer from the open position into the switching position and locked in the switching position, and that the switch rod can be released in a position of the latch unlocked for pivoting by pivoting the latch for the transfer from the switching position into the open position. The invention also relates to a method for switching the vacuum switch.

Full Text

The invention relates to a vacuum switch for railroad operation with at least two switching contitts and a drive system with a switch rod moving at least one switching contact. Such vacuum switches are employed as main switches for rail vehicles, for example for A. C. working. Therefore, the vacuum switches are designed for a high number of cycles, for example 250,000 operating cycles. In most cases, the vacuum switches are attached to the roof of a vehicle and connect the current collector with the main transformer. In the process, currents of up to 1000 A and voltages in the range of 15 kV to 25 kV are switched. Furthermore, these vacuum switches serve as protection against short circuits and overcurrents as well as overvoltages. Usually, in such vacuum switches, the drive of the switch rod moving the switching contacts is performed via a pneumatic drive. Therefore, for closing the switching contacts, compressed air is admitted to the vacuum switch. The switch rod is connected to a piston which is moved upwards by the compressed air, also pushes the switch rod upwards, preloads release springs and effects a closing of the switching contacts. The piston is held in the closed position of the switching contacts via an electromagnet. For opening the switching contacts, the electromagnet is released, the piston is released and the switch rod is shifted downwards by the release springs. Such pneumatic drives have a number of disadvantages. Complex pneumatic dressing with water separators and dust collectors is necessary to prevent dirt and moisture from being carried along. Therefore, the pneumatic system requires a lot of space. The pneumatic systems furthermore require frequent maintenance and are susceptible to problems mainly at low temperatures. After relatively long downtimes of the rail vehicle, problems with the air supply can arise, i.e. the pressure of the pneumatic system can drop so far that the pressure required for switching is no longer achieved. It is therefore the object of the present invention to provide a vacuum switch for railroad operation that is thermally stable and independent of compressed air, can do with only little switch-on energy and meets the precise demands on the opening dynamics. To this end, the invention envisages that the drive system further comprises a main spring transferring the switch rod from an open position into a switching position, a drive for preloading the main spring, a locking mechanism for locking the main spring in the preloaded state, and a pivoted latch, the latch being arranged so as to be longitudinally shifted at least in a position locked against pivoting such that the switch rod can be released by means of the latch during the trarMer from the open position into the switching position and locked in the switching position, and that the switch rod can be released in a position unlocked for pivoting of the latch by pivoting the latch for the transfer from the switching position into the open position. The drive system according to the invention comprises a drive coupled with a spring energy store. The main spring can be preloaded in operation by means of the drive and locked in the preloaded state. For closing the switching contacts of the vacuum switch, therefore only little energy is required for releasing the locking of the main spring. Even after a relatively long downtime, there are no problems with switching on. When the locking is released, the main spring releases, the stored spring energy is transmitted to the switch rod so that the switch rod is transferred from the open position into the switching position. The spring force of the main spring is changed over the spring excursion so that the desired opening dynamics is achieved. The arrangement of the latch in such a manner that the same can be longitudinally shifted and pivoted permits a release of the switch rod into both directions of the switch rod movement. In the upward movement of the switch rod, the latch is moved into the longitudinal direction, so that the switch rod can be brought into the switching position. Thus, the upward movement is dampened. For transferring the switch rod into the open position, the latch is pivoted. In the position locked against pivoting, the latch locks a downward movement, absorbs impacts occurring during driving and prevents an unintentional opening of the switching contacts. Preferably, the drive can be an electromotive drive. Thus, the disadvantages in connection with the pneumatic system, such as pneumatic dressing, high space requirements and the problems with thermal fluctuations, are avoided. In a preferred embodiment, the latch can comprise an electric holding magnet for locking the latch in the position locked against pivoting and for unlocking the latch in the position unlocked for pivoting, wherein the latch is locked in the current-carrying state of the electric holding magnet and unlocked in the currentless state of the electric holding magnet. In this manner, a failsafe vacuum switch is achieved. If a mains failure occurs, the electric holding magnet releases the locking of the latch, the latch is opened, the switch rod is transferred to the open position, the switching contacts are opened and are in a safe state. Advantageously, the electric holding magnet is arranged at the end of the latch facing away from the switch rod. By this measure and the resulting lever action, the retention force required can be reAflfced. A further adaptation of the retention force is possible by changing the distance between the pivot of the latch and the position of the electric holding magnet. In another preferred embodiment the latch can comprise a spring acting in the longitudinal shifting direction of the latch. When the switch rod is transferred from the open position into the switching position, the latch is shifted against this spring and, when the switch rod is in the switching position, it is returned to its locked position by the spring. The switch rod is locked in the switching position; unintentional opening by impacts etc. in operation is prevented. The spring is preferably a pressure spring, however, it is also possible to employ tension springs. Advantageously, the latch and the switch rod comprise run-up ramps associated one to another which are arranged adjacent one to another when the switch rod is transferred from the open position into the switching position. Due to the inclined run-up ramps, the longitudinal shifting of the latch during the transfer of the switch rod from the open position into the switching position is facilitated. The switch rod and the latch slide past each other more easily. Preferably, the switch rod can comprise an undercut in which the latch is engaged in the switching position. This undercut can also be formed by the end face of the switch rod. The latch engages in the switch rod when the same has reached the switching position and thus prevents the switch rod from sliding back into the open position. Even in case of impacts generated in operation, an unintentional opening of the switching contacts can be prevented due to this positive locking. In one variant, the latch can be connected to a damper. With this damper, the pivoting movement of the latch is dampened in both end positions to avoid hard striking of the armature of the electric holding magnet at an upper stop and on the electric holding magnet. In another variant the switch rod can comprise a return mechanism for transferring the switch rod into the open position. If the latch is in the position unlocked for pivoting, the return mechanism moves the switch rod into the open position and the switching contacts are opened. By the return mechanism, at least the force that is required for pivoting the latch in the position unlocked for pivoting and for opening possibly stuck contacts is applied. Preferably, the return mechanism can comprise at least one readjusting spring. The opening of the switching contacts is thus also performed by stored energy. Preferably, pressure springs that are compressed in the switching position and released in the open position are employed as readjusting springs. However, it is also possible to employ tension springs. Another functional embodiment provides for the main spring to be connected to the switch rod by means of a coupling means acting in dependence of the switching status, such that the main spring and the switch rod are coupled during the transfer of the switch rod from the open position into the switching position and uncoupled in the switching position. The coupling means permits to only temporarily connect the main spring with the switch rod. Thereby, the main spring can be preloaded in the switching position of the switch rod without acting on the switch rod. Advantageously, the energy stored in the main spring is higher than the energy required for transferring the switch rod from the open position into the switching position. By the active uncoupling, the main spring can oscillate back after the transfer of the switch rod into the closed position and relieve the residual energy. This residual energy does not have to be absorbed in further components of the vacuum switch. Preferably, the electromotive drive can be connected to the main spring by means of a shaft. In this manner, a very simple connection between main spring and motor shaft is achieved. The main spring can be eccentrically arranged at the shaft with an end region thereof. In the preloaded state, the spring therefore applies a torque on the shaft so that the same rotates when the locking mechanism is unlocked and the energy stored in the main spring is transferred to the switch rod via the coupling means. Advantageously, the coupling means can comprise a coupler mechanism, wherein the main spring is connected to the switch rod by means of the coupler mechanism. By using a coupler mechanism, a more compact design of the drive system is possible. In a preferred embodiment, the coupler mechanism can comprise at least one cam arranged at the shaft. In this manner, it is simply permitted that the main spring is only temporarily connected to the switch rod during the rotation of the shaft. Preferably, the cam is actively connected to a lever connected to the switch rod during the transfer of the switch rod from the open position into the switching position. The cam engages with one end of the lever and moves this end downwards. The other end of the lever is connected to the switch rod and is therefore moved upwards. Due to the lever action achieved thereby, the employment of a weaker main spring is possible. In a particularly preferred embodiment, the cam is designed such that it is actively connected to the lever in an angular field of maximally 240°. It is thus ensured that the cam does not engage with the lever when the main spring is being preloaded by means of the shaft and the electromotive drive. Another preferred embodiment provides for the locking mechanism to comprise an electric release magnet and the locking mechanism to be unlocked in the current-carrying state of the electric release magnet. In this manner, too, an operationally reliable vacuum switch is provided: in a currentless state, the retaining spring is locked by the locking mechanism and the switching contacts therefore remain in the open position. In this locking state, no retention energy is required. For switching on the vacuum switch, only little switching-on energy is necessary which is required for activating the release magnet, thus opening the locking mechanism and thereby transmitting the energy stored in the main spring to the switch rod. Advantageously, it can be provided for the locking mechanism to comprise a first catch connected to the main spring and a second catch connected to the electric release magnet, the first catch being engaged with the second catch in the locked state. Thus, a simple realization of the locking mechanism is possible. If energy is applied to the electric release magnet, the second catch is retracted by the release magnet, thereby the first catch is unlocked and the stored spring energy is transmitted to the switch rod. By the connection of the main spring with the first catch, a compact design of the drive system is possible. A further functional embodiment provides for the switch rod to be connected to at least one of the switching contacts by means of a toggle link. In this manner, a favorable arrangement of the vacuum switch on the vehicle roof is possible. A variant provides for the toggle link to comprise a spring-actuated mechanism and for the switching contacts to be adjusted by means of the spring-actuated mechanism. Thereby, no readjustment of the springs or the toggle link is necessary, whereby a low-maintenance design is achieved. Moreover, the invention also relates to a method for switching the switching contacts of an above-described vacuum switch. The method comprises the following steps: positioning the switch rod in the switching position, transferring the latch into the position unlocked for pivoting, transferring the switch rod into the open position by means of the return mechanism. This method permits a reliable switching of the vacuum switch. For opening the switching contacts, the latch is transferred into the position unlocked for pivoting and pivoted about a pivot. According to a variant of the method, it is provided for the positioning of the switch rod in the switching position to comprise the following steps: transferring the latch into the position locked against pivoting, unlocking the locking mechanism of the main spring, transferring the switch rod from the open position into the switching position, preloading the main spring, and closing the locking mechanism of the main spring. For closing the main contacts, only the little energy required for holding the latch in the position locked against pivoting as well as the pulse energy for unlocking the locking mechanism of the main spring are necessary. The switching on of the vacuum switch is therefore also possible with weak batteries. As the main spring is already preloaded again in the operating state, the vacuum switch is again in a standby state after the opening of the switching contacts and the stored spring energy can be immediately used for switching on. Below, an embodiment of the invention will be illustrated more hi detail by means of a drawing. In the drawings: Fig. 1 shows a side view of the vacuum switch in a non-operative state with released main spring, Fig. 2 shows a side view of the vacuum switch when the main spring is being tensioned, Fig. 3 shows a side view of the vacuum switch in a standby state with loaded main spring, Fig: 4 shows an exploded view of the drive system and the vacuum interrupter chamber of the vacuum switch when the main spring is being tensioned, Fig. 5 shows a side view with a partially sectional representation of the vacuum switch in the open position of the switch rod with loaded main spring, Fig. 6 shows a side view with a partially sectional representation of the vacuum switch during the transfer of the switch rod from the open position into the switching position, Fig. 7 shows a side view with a partially sectional representation of the vacuum switch in the switching position of the switch rod, Fig. 8 shows the latch in the position locked against pivoting during the transfer of the switch rod from the open position into the switching position, Fig. 9 shows the latch in the position locked against pivoting, wherein the switch rod is in the switching position, and Fig; 10 shows the latch in the position unlocked for pivoting during the transfer of the switch rod from the switching position into the open position. In Fig. 1, a side view of a vacuum switch 1 is represented. Such a vacuum switch 1 is, for example, used in rail vehicles for connecting the current collector with the main transformer. The vacuum switch 1 comprises a switch element 2 in which a vacuum interrupter chamber is arranged. The vacuum interrupter chamber comprises switching contacts which can be closed and opened via a drive system 3. Usually, such a vacuum switch 1 is fixed to the roof of the rail vehicle by means of a mounting plate 4. In this case, the drive system 3 can be fixed on the mounting plate 4, that means on the outside of the vehicle, or under the mounting plate 4, that means on the inside of the vehicle. The components arranged at the outside of the vehicle are surrounded by insulators 30 and are protected from environmental influences. The drive system 3 comprises a switch rod 5 which is connected to at least one of the switching contacts to move the same for switching the vacuum switch 1. The drive system 3 furthermore comprises a main spring 6 by means of which the switch rod 5 can be transferred from an open position in which the switching contacts are opened into a switching position in which the switching contacts are closed. The main spring 6 is preferably a tension spring which is represented in a released state in Fig. 1. The main spring 6 is connected to the mounting plate 4 at onf snd 7 thereof. At its other end, the main spring 6 is eccentrically connected to a shaft 9. The shaft 9 is connected to an electromotive drive 10 (see Fig. 4). By means of the electromotive drive 10, the shaft 9 is rotated and the main spring 6 eccentrically connected to the shaft 9 is preloaded for storing spring energy. In Fig. 2, an intermediate state during the loading of the main spring is represented, the preloaded state of the main spring 6 is shown hi Fig. 3. The main spring 6 is locked in the preloaded state via a locking mechanism 11. hi the locked state of the main spring 6, no retention energy has to be provided. The main spring 6 is connected to the switch rod 5 via a coupling means which only temporarily, i.e. only in a certain angular field during the rotation of the shaft 9, actively connects the main spring 6 to the switch rod 5 (see Fig. 5 - Fig. 7). There is an active connection between the main spring 6 and the switch rod 5 when the switch rod 5 is being transferred from the open position into the switching position. If the switch rod 5 is in the switching position, the main spring 6 and the switch rod 5 are uncoupled. Furthermore, at least one cam 12 is arranged at the shaft 9. The cam 12 is arranged on the shaft 9 such that in the preloaded state of the main spring 6 it is positioned adjacent to a lever 13 connected to the switch rod 5 and rotated about a pivot arranged between the cam 12 and the switch rod 5. The locking mechanism 11 is arranged such that the main spring 6 eccentrically acting on the shaft 9 is locked over its dead center in the preloaded state (see Fig. 5). The electromotive drive 10 is connected to a snap switch which is arranged just above the dead center of the main spring 6. If the main spring 6 passes the dead center, the snap switch switches off the electromotor 10 and the main spring 6 is pulled against the locking mechanism 11 by its spring energy. The main spring 6 therefore exerts a torque on the shaft 9 which has the same sense of rotation as the preloading motion of the shaft 9. If the locking mechanism 11 is now being unlocked, the shaft 9 is rotated by the main spring 6 into the same direction as during the preloading of the main spring 6. In the process, the cam 12 acts on the lever 13 such that the switch rod 5 is shifted from the open position into the switching position. The cam 12 is designed such that it maximally contacts the lever 13 over an angle of 240°. During the preloading of the main spring 6, the cam 12 does not come into contact with the lever 13, so that the switch shaft 5 is uncoupled from the main spring 6 in this state (see Fig. 6 and Fig. 7). > In the embodiment represented in Figures 1-7, the locking mechanism 11 comprises a catch system. The main spring 6 is arranged at the shaft 9 by means of a first catch 14. This catch lies against a second catch 15 in the locked state of the main spring 6. The second catch 15 is connected to an electric release magnet 16 which retracts the catch 15 in a current-carrying state. Thereby, the catch 14 slips through a recess 32 in the catch 15 and is released, the shaft 9 is 'rotated by means of the main spring 6 so that the cam 12 is engaged with the lever 13 and the switch rod 5 is transferred from the open position into the switching position. The locking mechanism 11 furthermore comprises a spring (not represented) which presses the catch 15 outwards when the release magnet 16 is in a currentless state. As is represented in Fig. 4, the switch rod 5 is connected to the switching contacts via a toggle link 17. The toggle link 17 comprises a spring-actuated mechanism 18 which automatically adjusts the switching contacts. When the contacts erode, the springs of the spring-actuated mechanism 18 further press the switching contacts against each other and take care that the minimum contact pressure is reached. Therefore, no maintenance or readjustment of the switching contacts is necessary. Moreover, the switch rod 5 comprises a return mechanism, for example readjusting springs 26, which are preloaded when the switch rod 5 is transferred from the open position into the switching position. By means of the spring energy stored in the readjusting springs 26, the switching contacts can be opened again. The drive system 3 furthermore comprises a latch 19 which locks the switch rod 5 in the switching position. This latch 19 is shown in detail in Figures 8 to 10. Fig. 8 shows the cooperation of the latch 19 and the switch rod 5 during the transfer of the switch rod 5 from the open position into the switching position. The latch 19 comprises an electric holding magnet 20 with an armature 21. The electric holding magnet 20 is connected to the latch 19 via a lever 31. This lever 31 can be resilient. In a current-carrying state, the electric holding magnet 20 attracts the armature 21 and thus locks the latch 19 in a position locked against pivoting. If the switch rod 5 is now moved upwards by the main spring 6 for the transfer from the open position into the switching position, the run-up ramp 22 arranged at the switch rod 5 contacts the run-up ramp 23 of the latch. The run-up ramps 22,23 facilitate the slipping of the switch rod 5 past the latch 19. During this slipping past each other, the latch 19 is shifted longitudinally and pressed against a spring 24. The switch rod 5 comprises an undercut 25 which engages in the latch 19 when the switch rod reaches the switching position. In the represented case, the undercut 25 is the end face of the switch rod 5. The engagement of the latch 19 in the undercut 25 is effected by the spring 24 pressing the latch 19 into the undercut 25. The undercut 25 and the spring 24 are designed such thriven in case of vibrations in railroad operation, the latch 19 does not slip out of the undercut far enough for the switch rod 5 to be unlocked. The readjusting springs 26 exert a force on the switch rod 5 which presses the same downwards against the latch 19 when the switch rod 5 is in the switching position (see Fig. 9). When the switching contacts are opened, the electric holding magnet 20 is switched to be currentless, so that there is no more attraction of the armature 21 (see Fig. 10). The latch 19 is now in a position unlocked for pivoting. The readjusting springs 26 press the switch rod 5 downwards, so that the latch 19 is pivoted about its pivot 27. The lower end 28 of the latch 19 moves downwards, is released from the undercut 25 of the switch rod 5 and releases the switch rod 5. The switch rod 5 is pressed into the open position by the readjusting springs 26. For dampening the pivoting movement of the latch 19 into its end positions, the latch 19 comprises a damper 29. Below, now the switching of the switching contacts of the vacuum switch is illustrated more in detail, starting from the standby state of the switch. In the standby state, the main spring 6 is in the preloaded state and held in this state by the locking mechanism 11, the switching contacts are opened, the switch rod 5 is in the open position. If the switching command is given, the electric holding magnet 20 is connected to the power supply, therefore attracts the armature 21 and locks the latch 19 in the position locked against pivoting. The battery voltage is applied to the electric release magnet 16, and thereby the catch 15 of the locking mechanism 11 is retracted. Thereby, the catch 14 is unlocked, the main spring 6 contracts and rotates the shaft 9. The cam 12 engages with the lever 13 whereby the switch rod 5 is moved upwards and transferred from the open position into the switching position. During the transfer of the switch rod 5 from the open position into the switching position, the runup ramp 22 of the switch rod 5 and the run-up ramp 23 of the latch 19 slip past each other, the latch 19 is longitudinally shifted against the spring 24 until the undercut 25 of the switch rod 5 reaches the upper end of the latch 19. The spring 24 presses the latch 19 into the undercut 25 of the switch rod 5 and locks the switch rod 5 in the switching position. In the process, the readjusting springs 26 are loaded and held in their preloaded positions by means of the latch 19 and the electric holding magnet 20. The cam 12 and the lever 13 are now no longer engaged. As tbte energy stored in the main spring 6 is higher than the energy required for transferring the switch rod 5 from the open position into the switching position, the shaft 9 is further rotated by the remaining spring energy and the main spring 6 oscillates in the released position. The 'fqjtodning spring energy does not have to be absorbed in components of the vacuum switch. The switching contacts are now closed and the vacuum switch 1 is thus in its operative state. Then, the electromotive drive 10 is started and again preloads the main spring 6 by means of the shaft 9. If the catch 14 passes the dead center of the main spring 6 and passes the snap switch, the electromotive drive 10 is switched off by the snap switch. The catch 14 is pulled against the catch 15 via the main spring 6 and not driven against it with the full motive power. The preloaded main spring 6 is held in the preloaded state via the locking mechanism 11. If the opening command is given, the electric holding magnet 20 is switched off, so that the armature 21 is no longer attracted. The readjusting springs 26 push the switch rod 5 downwards. Thereby, a force is exerted on the latch 19 and the latch 19 is pivoted downwards about its pivot 27. This releases the switch rod 5 which is transferred into the open position, the switching contacts are opened. As the main spring 6 has already been preloaded in the operative state, the vacuum switch is again in its standby state. For a new closing operation, therefore only energy for the switch-on pulse for releasing the catch 14 has to be provided by the onboard network. Thereby, a closing of the vacuum switch is even possible after hours or days without essential energy from the vehicle battery. It is also possible to transfer the vacuum switch 1 into a non-operative condition. In the non-operative condition, the switching contacts are opened, the switch rod 5 is in the open position and the main spring 6 released. The vacuum switch 1 is characterized in that it comprises a fully electromechanical drive independent of compressed air. Therefore, no problems due to insufficient pressure of the compressed air can arise when the vehicle is started. As the switching operation is started by the energy stored in the main spring 6, switching on is even possible with low battery voltage. The vacuum switch 1 can also be easily installed for retrofit applications as no additional means, such as compressed air piping, water separators or dust collectors, are required. Due to the independence from compressed air, moreover a safe operation even in extreme temperatures is permitted; maintenance costs are lower. Moreover, the vacuum switch 1 has a double fail-safe principle: in case of mains failure, the electric holding magnet 20 of the latch 19 opens and transfers the latch 19 into the position unlocked for pivoting, so that the switching contacts are forced to open. The electric release magnet 16 of the locking mechanism 11 locks the catches 14 and 15 in a currentless state so that the vacuum switch is not switched on again. WE CLAIM: 1. Vacuum switch (I) for railroad operation with at least two switching contacts and a drive system (3) with a switch rod (5) moving at least one switching contact, characterized in that the drive system (3) further comprises a main spring (6) transferring the switch rod (5) from an open position into a switching position, a drive (10) for preloading the main spring (6), a locking mechanism (11) for locking the main spring (6) in the preloaded state, and a pivoted latch (19), wherein the latch (19) is arranged to be shifted longitudinally at least in a position locked against pivoting, such that the switch rod (5) can be released by means of the latch (19) during the transfer from the open position into the switching position and can be locked in the switching position, and the switch rod (5) can be released in a position of the latch (19) unlocked for pivoting by pivoting the latch (19) for the transfer from the switching position into the open position. 2. Vacuum switch (1) according to claim 1, characterized in that the drive (10) is an electromotive drive. 3. Vacuum switch (1) according to claim 1 or 2, characterized in that the latch (19) comprises an electric holding magnet (20,21) for locking the latch (19) in the position locked against pivoting and for unlocking the latch (19) in the position unlocked for pivoting, wherein the latch (19) is locked in the current-carrying state of the electric holding magnet (20, 21) and unlocked in the currentless state of the electric holding magnet (20,21). 4. Vacuum switch (1) according to claim 3, characterized in that the electric holding magnet (20,21) is arranged at the end of the latch (19) facing away from the switch rod (5). 5. Vacuum switch (1) according to one of claims 1 to 4, characterized in that the latch (19) comprises a spring (24) acting in the longitudinal shifting direction of the latch (19). 6. Vacuum switch (1) according to one of claims 1 to 5, characterized in that the latch (19) and the switch rod (5) comprise run-up ramps (22,23) associated to one another which are arranged adjacent one to another during the transfer of the switch rod (5) from the open position into the switching position. 7. Vacuum switch (1) according to one of claims 1 to 6, characterized in that the switch rod (5) comprises an undercut (25) in which the latch (19) is engaged in the switching I position. 8. Vacuum switch (1) according to one of claims 1 to 7, characterized in that the latch (19) is connected to a damper (29). 9. Vacuum switch (1) according to one of claims 1 to 8, characterized in that the switch rod (5) comprises a return mechanism for transferring the switch rod (5) into the open position. 10. Vacuum switch (1) according to claim 9, characterized in that the return mechanism comprises at least one readjusting spring (26). 11. Vacuum switch (1) according to one of claims 1 to 10, characterized in that the main spring (6) is connected to the switch rod (5) by means of a coupling means acting in dependence of the switching state, such that the main spring (6) and the switch rod (5) are coupled during the transfer of the switch rod (5) from the open position into the switching position and uncoupled in the switching position. 12. Vacuum switch (1) according to one of claims 1 to 11, characterized in that the electromotive drive (10) is connected to the main spring (6) by means of a shaft (9). 13. Vacuum switch (1) according to claim 12, characterized in that the main spring (6) is eccentrically arranged at the shaft (9) with one end region (8) thereof. 14. Vacuum switch (1) according to one of claims 1 to 13, characterized in that the coupling means comprises a coupler mechanism, wherein the main spring (6) is connected to the switch rod (5) by means of the coupler mechanism. 15. Vacuum switch (1) according to claim 14, characterized in that the coupler mechanism comprises at least one cam (12) arranged at the shaft (9). 16. Vacuum switch (1) according to claim 15, characterized in that the cam (12) is actively connected to a lever (13) which is connected to the switch rod (5) during the transfer of the switch rod (5) from the open position into the switching position. 17. Vacuum switch (1) according to one of claims 15 or 16, characterized in that the cam (12) , is designed such that it is actively connected to the lever (13) in an angular field of maximally 240°. 18. Vacuum switch (1) according to one of claims 1 to 17, characterized in that the locking mechanism (11) comprises an electric release magnet (16) and the locking mechanism (11) is unlocked in the current-carrying state of the electric release magnet (16). 19. Vacuum switch (1) according to one of claims 1 to 18, characterized in that the locking mechanism (11) comprises a first catch (14) connected to the main spring (6) and a second catch (15) connected to the electric release magnet (16), wherein the first catch (14) is engaged with the second catch (15) in the locked state. 20. Vacuum switch (1) according to one of claims 1 to 19, characterized in that the switch rod (5) is connected to at least one of the switching contacts via a toggle link (17). 21. Vacuum switch (1) according to claim 20, characterized in that the toggle link (17) comprises a spring-actuated mechanism (18) and the switching contacts can be adjusted by means of the spring-actuated mechanism (18). 22. Method for switching the switching contacts of a vacuum switch (1) according to one of claims 1 to 21, characterized by the following steps: positioning the switch rod (5) in the switching position, transferring the latch (19) into the position unlocked for pivoting, and transferring the switch rod (5) into the open position by means of the return mechanism. 23. Method according to claim 22, characterized in that the positioning of the switch rod (5) into the switching position comprises the following steps: transferring the latch (19) into the position locked against pivoting, unlocking the locking mechanism (11) of the main spring (6), transferring the switch rod (5) from the open position into the switching position, preloading the main spring (6), and closing the locking mechanism (11) of the main spring (6). 24. A vacuum switch and a method for switching the switching contacts of a vacuum switch substantially such as herein described with reference to accompanying drawings.

Documents:

1967-del-2004-Abstract-(10-09-2014).pdf

1967-del-2004-Claims-(10-09-2014).pdf

1967-del-2004-Correspondence Others-(10-09-2014).pdf

1967-del-2004-Drawings-(10-09-2014).pdf

1967-del-2004-Form-2-(10-09-2014).pdf

1967-del-2007-Abstract-(10-04-2013).pdf

1967-del-2007-Abstract-(10-09-2014).pdf

1967-del-2007-abstract.pdf

1967-del-2007-Claims-(10-09-2014).pdf

1967-del-2007-claims.pdf

1967-del-2007-Correspondence Others-(10-04-2013).pdf

1967-del-2007-Correspondence Others-(10-09-2014).pdf

1967-del-2007-Correspondence Others-(19-02-2013).pdf

1967-del-2007-correspondence-others 1.pdf

1967-DEL-2007-Correspondence-Others.pdf

1967-del-2007-description (complete).pdf

1967-del-2007-drawings.pdf

1967-DEL-2007-Form-1.pdf

1967-del-2007-form-18.pdf

1967-del-2007-Form-2-(10-09-2014).pdf

1967-del-2007-form-2.pdf

1967-del-2007-form-26.pdf

1967-del-2007-Form-3-(10-04-2013).pdf

1967-del-2007-form-3.pdf

1967-del-2007-form-5.pdf

1967-del-2007-GPA-(10-04-2013).pdf

1967-del-2007-Petition-137-(10-04-2013).pdf