Manual drive for step transformer winding tap changers

FIELD: electricity.

SUBSTANCE: invention relates to a manual drive for stepwise control of a step transformer winding tap changer with a locking device, without power consumption. Besides, there is a master shaft, on which per one change there are several manual rotations implemented. There is also a control mechanism, which converts these rotations exactly into one rotation of a geared wheel per one change. The locking mechanism comprises a rotary inner key and a latch rotating around the axis of rotation and a stop, which corresponds to the stop slot of the master shaft, and a stop cam, which corresponds to the slot of the geared wheel of the control mechanism. Due to actuation of the inner key, the latch rotates from the locked position so that the stop and the stop cam are disengaged from the appropriate slots.

EFFECT: higher reliability of protection in respect to undeliberate or deliberate incorrect usage of a manual drive.

7 cl, 10 dwg

 

The invention relates to a manual drive for step-by-step, without power control tap changer step transformer.

Such manual drive is known from DE-OS 3541888. It consists of a body, drive shaft, provided with a turning handle the driven shaft, a gear mechanism located between them, and the digital display for the corresponding switched position of the tap changer.

Other manual actuator known in the original print edition of this applicant's "Manual drive BM75, instruction manual BA109/03", published in July 2004, And it has a swivel handle for manual control. This manual drive for security provided unblocking lever that after each operation the switch should be locked with a padlock to prevent unauthorized use of the player. Control is also provided a locking pin, which switches simultaneously with controlling the unblocking lever.

From another brand printed editions of this applicant's "Manual drive MR404 - instruction manual BA23/02", published in August 2004, known one manual actuator, in which the rotary handle can be removed with the drive shaft and is attached to the outside of the building with SIP is using spring clamps. In this embodiment, the actuator is released by turning the key. When the locking lever is removed from the lock washers and wheels with Cams; drive shaft is released and can be rotated. Using low gear shaft leading to the tap changer, always rotates at one revolution per switch, regardless of the number of turns on one switch is needed on the swivel arm. At the end of the switch using the springs mentioned locking lever fixed again, entering into the notch of the locking washer and the wheel with Cams, so that the actuator is blocked. At the same time switches the electrical Cam switch. Because of the forced lock new switching can be performed only after repeated rotation of the key.

Summarizing, we can characterize the prior art such manual actuators as follows: there are three mechanical construction unit, namely, the power transmission is used to transfer the applied to the steering handle of the torque to the tap changer, the control mechanism used to transfer rotary motion from the handle to the mechanism for indicating and adjustment, it is possible, the available funds forced the lock, and the mechanism Indyk is tion, used for visualization of operating positions of the tap changer, as well as for counting completed switching. Known manual actuators are equipped with safety devices that should prevent their use by unauthorized persons.

However, it turned out that the manual actuators, as they are generally intended for use outdoors and in many cases are mounted without control, subject to numerous attempts to use contrary to the intended purpose. Partly it's about the Amateurs who simply ignore attached to the instrument instruction manual, partly as deliberate attempts to misuse or vandalism. Along with the inevitable in this case, damage to the instrument or impaired operation of a step transformer is, in particular, it is risky from the point of view warranty.

The objective of the invention is to provide a manual drive of the aforementioned type, which ensures the highest possible mechanical and electrical protection against misuse and attempted misuse of any kind.

This problem is solved by using the manual actuator with the characteristics of the first claim. Dependent claims relate to preferred the compulsory advanced embodiments of the invention.

The invention manual drive contains, in accordance with the prior art, already described structural components - power transmission, control mechanism and the display mechanism. In accordance with the invention, the control mechanism includes when the locking device, which is provided with a latch receiving efforts if outsiders want to switch, contrary to the purpose, not using the unblocking device. The invention proposes in General, the greatest possible protection against misuse, whether inadvertently through ignorance or deliberately.

Next, you need to explain the invention in more detail using the drawings. The figures shown:

Figure 1 - the locking device proposed by the invention of a manual actuator in the locked state of the rear, i.e. rotated from the user side of body,

Figure 2 - the same locking device, shown from the side,

Fig.3-9 shows the locking device at different points in time during the preparation and holding of the switch, i.e. the use of a manual drive, front, namely:

Figure 3 - after removing the protective padlock,

Figure 4 - after further rotation of the control element in the end position,

5 - at the beginning of rotation of the inserted rotary rucola the key,

6 - upon further rotation of the rotary handle,

Fig.7 - shortly before the end of shift,

Fig after the switch,

Fig.9 - subsequent jammed.

Figure 10 is a complete manual actuator, shown in perspective from the front.

First, you need more clarification on figures 1 and 2, showing the invention the locking device in a stationary protected status. Outside not shown is the external key 1, which formed the outer element 2 control. This outer element 2 control corresponds to a stationary second element 3, to which it is attached in a secure condition and locked in this position a padlock 4, which is threaded through the holes as the outer element 2, and the stationary response of the element 3. The outer element 2 control connected with internal key 5, which is provided with a Cam 6, and contains the locking finger 7. The outer element 2 management, the external key 1 and the internal key 2 is made to rotate. In addition, latch 8, which is installed on the axis 9 of rotation. It has a groove 10, which corresponds to the fist 6 ensuring geometric circuit. At its opposite groove 10 side it has a locking circuit 11, which is suitable for the em stoparea finger 7 with providing geometric circuit, as will be explained in detail below. In addition, the latch 8 is provided the locking Cam 12, which can move around the axis 9 of rotation of the latch 8 with it. Preferably the locking Cam 12 can move perpendicular to the longitudinal length of the latch 8 by a certain amount. Described the locking Cam 12 corresponds to the groove 14 on the toothed wheel 15 of the control mechanism. Described stopper 13, in turn, corresponds stoparea groove 16 on the control shaft 17. In addition, it is shown the spring 18, which is pivotally connected with the internal key 5, and the spring 19, which is pivotally connected to the latch 8. Finally, it is also depicted the microswitch 20 is designed to control the power switch of the transformer, and the microswitch 21 which is used for forming electrical messages about the destruction of the castle.

In this position the internal key 5 is held in the shown position padlock 4.

On the following figures again marked with the numbers of positions respectively only necessary to explain the current position and the principle of structural elements. Figure 3 shows the locking device after removal of the padlock 4. Internal key 5 is rotated by the spring 18 90 degrees to the right. At the same time comes into effect microvisual 2, and electrically shows the removal of the padlock 4. It is seen that the driving shaft 17 is still locked with the stopper 13, which is fixed, entering into the locking groove 16.

Figure 4 shows the device after the full release, i.e. the further rotation of the control element in the end position. When this outer element 2 management and with the internal key 5, resisting the spring force, continue to turn to the right. As a result, he gets his Cam 6 on the latch 8, presses it down, and enters the locking in the groove 10. During this movement of the latch 8 actuates the microswitch 20 is designed to control the power switch of the transformer, which is provided on the transformer without tension. Only in the final position of this release, as shown in figure 4, is released drive shaft 17, because the stopper 13 is withdrawn from the locking groove 16. After that, the manual actuator is ready for operation; only now the driving shaft may be powered using worn swing arm. Up to this point in time it is still possible to interrupt provided for switching.

Figure 5 shows the device at the beginning of the rotation arm. The locking Cam 12 is not included in the groove 14. When the rotation of the swivel arm with the control mechanism rotates at the same time, what about the groove 14, when eight revolutions of the rotary arm groove 14 makes exactly one revolution. After the start of rotation of the locking Cam 12 moves to the groove 14 of its contour, and the Cam 6 by the force of the spring to pop out of the groove 10. This is shown in Fig.6. The release latch 8 for possible fixation with getting into the groove 16 of the drive shaft 17 occurs only after seven turnovers, as the gear wheel 15 and the groove 14 makes only one turn on one switch. To explain this example we are talking about eight revolutions of the drive shaft 17. However, it is not required; it is also possible number of turns. By appropriately calculating mechanism in each case, however, is provided to the groove 14 each time the switch was made exactly one revolution.

Internal key 5 is now not blocked by the groove 10, and the interaction of the locking finger 7, which now fell on the locking circuit 11. It is shown in Fig.7: the locking finger is locked loop 11.

On Fig shows the device after the completed switch, in which the stopper 13 is fixed in the groove and the driving shaft 17 is blocked by the stopper 13. As explained, the stopper 13 is again introduced into the locking groove 16 and at the same time, thanks to the spring 19, the entire latch 8 is rotated. Message microswitch 21 about the destruction of the castle in this position is still active.

From the depicted sequence it is clear that the invention device integrates various protective functions. On the one hand, the driving shaft 17 and remains blocked until it is removed padlock 4, and, in addition, quite deliberately item 2 management will not be turned on against the force of the spring 18 in the operating position. In addition, it is possible to implement only full switch, here consisting of eight revolutions of the drive shaft 17. This is due to the interaction of the locking Cam 12 and groove 14. If the user is switching after less than eight turnovers interrupts rotational motion, work is depicted in figure 5 or 6 of the intermediate state, in which the microswitch 20 leaves the circuit breaker of the transformer is disconnected and cannot be closed or, respectively, to lock the device. This is impossible because the wall key 5 remains blocked. In addition, it is impossible to produce more than eight turnovers, as it was after eight turns, i.e. full turns of the groove 14, the locking Cam latch 12 8 again sink down into this groove 14, it also returns to the locked drive shaft 17, because the latch 8 is turned around a point 9 rotation. This block can be overcome only very deliberately by repeated actuation of the external element 2 of the control.

Figure 10 again shows the invention of a manual actuator on the outside. Here is shown the rotary arm 22, which is typically worn on the body side, the hole 23 to enter this rotary arm 22, and the upper housing driven shaft 24 leading to the tap changer, which must be managed. In addition, it is also shown the position indicator 25, which displays the corresponding current is included in a branch of the tap changer, and the indicator 26 step switch and the counter 27. Indicator 26 step switch makes the gear exactly one revolution, similar to the groove 14 on the toothed wheel 15 of the control mechanism, and informs thereby about the current state of the corresponding schema end off. If the arrow of the indicator 26 step switch again reached its initial put what I switching over.

1. Manual drive for step-by-step without power control tap changer step transformer,
and provided a drive shaft on which one of the switch through several revolutions manually
moreover, a mechanism of control, which converts these turns at exactly one revolution of the gear wheel in one switch,
and moreover provided by the locking device so that the drive shaft is blocked by the stopper, which is included with the lock in the locking groove of the drive shaft until then, until it is done manually enabled using the external rotating element of service,
characterized in that
the locking device includes a rotating inner key (5), which is connected with an external element (2) maintenance,
when the locking device also includes a pivotable around an axis (9) rotate the latch (8)containing the stopper (13), which corresponds to stoparea groove (16) of the drive shaft (17)and the locking Cam (12), which corresponds to the groove (14) of the gear mechanism (15) control,
due to the actuation of the internal key (5) latch (8) is rotated from a locked position so that the stopper (13) and the locking Cam (12) disengage from choosing the corresponding grooves (14, 16).

2. Manual drive according to claim 1, characterized in that the internal key (5) comprises a Cam (6)and the locking finger (7), the latch (8) at its free end has a corresponding fist (6) of the groove (10)and the corresponding stoparea finger (7) the locking circuit (11).

3. Manual drive according to claim 2, characterized in that the stopper (13) is located on the opposite groove (10) the free end of the latch (8).

4. Manual drive according to claim 1, characterized in that the internal key (5) pivotally connected spring (18) in such a way that against the force of the spring (18) internal key (5) is pressed into the position of release.

5. Manual drive according to claim 1, characterized in that the latch (8) pivotally connected spring (19).

6. Manual drive according to claim 1, characterized in that it includes a microswitch (20), which controls the circuit breaker of the transformer and, in turn, is controlled by a latch (8) when removing it from the locked position.

7. Manual drive according to claim 1, characterized in that it includes a microswitch (21), which delivers an electrical signal on the enable is driven by the internal key (5).



 

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