JPS6361734B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an electric operating device for a low voltage switch, which is equipped with a sliding plate that engages with the operating handle of the low voltage switch and is guided by a support base, and a limit switch for stopping the electric motor at a terminal position. Involved.

When maintenance work is to be carried out on equipment that is supplied with power from the mains via a low-voltage switch, the equipment must be de-energized for safety reasons. This is generally done by opening the low voltage switch and preventing its re-opening by closing, securing or similar means. However, when the low-voltage switch is equipped with an electric actuator, such protection measures are difficult to implement, since the electric actuator can usually be controlled remotely from a control room or similar control device. The difficulty becomes even greater when the electric actuator is also adapted for manual operation, since it is necessary to prevent the closing of the low-voltage switch by remote control as well as by manual operation.

The object of the invention is to construct a power actuator of the above-mentioned type in such a way that remote and manual operation of the low-voltage switch is prevented by the use of a simple safety element, for example a padlock.

An object of the present invention is to provide a two-arm rotary lever that is swingably supported on a support base, and whose first arm rotates around its bearing when the low voltage switch is opened, and the first arm of the lever rotates around its bearing to bring the lever into contact with the abutment surface. It is possible to block the path of the sliding plate and to swing it in such a way as to drive the limit switch operator on its active surface, while its second arm has a safety element that prevents the rotary lever from returning to its initial position. This is achieved by being installable. With such a method, the two desired functions are performed by one component, namely a two-arm rotary lever and one working step.

Preferably, a spring is provided which urges the rotary lever into its initial position. After removing the safety element, the electric actuator will then automatically perform its normal function.

Between the bearing and the limit switch, a guide can be provided on the support of the electric actuator, which acts on the rotary lever from both sides. With this guide,
It is possible to use bearings with relatively large dimensional differences for the rotary lever without compromising the interaction between the first arm and the limit switch.

If a cover is provided to protect the electric actuator from contact or environmental influences, the cover shall have at its free end a second arm provided with a hole for the passage of one or more padlock latches. It can have a slit for passing through, the wall of the cover being folded close to the slit so that it is difficult to bend. In this way, even a plastic cover with a relatively thin wall thickness can withstand the loads due to the use of the above-mentioned safety elements.

Next, the present invention will be explained in detail based on the illustrated embodiments. Figure 1 is a partial side sectional view of a low-voltage switch with an electric actuator attached, Figure 2 is a plan view of the electric operator with the cover removed, and Figure 3 is a sectional view perpendicular to the cross section of Figure 1. , FIGS. 4 and 5, and FIGS. 6 and 7 are a side view and a plan view, respectively, of two embodiments of a two-arm rotary lever with a bearing stand as a subassembly.

In FIG. 1, a low-voltage switch 1 is partially illustrated. Only the upper part of the case of the low voltage switch 1 is shown, and an operation handle 2 protrudes from the front side thereof, whereby the low voltage switch 1 can normally be opened and closed by hand. An electric operating device, generally designated 3, is fixed to the case of the low-voltage switch 1, and includes a support 4 and a sliding plate 5 guided by the support 4. Similarly, the electric motor 6 with a reduction gear fixed to the support base 4 is connected to the crank arm 1.
0 is used to drive the sliding plate 5 in the direction of the arrow 7. The sliding plate 5 has a hole and a bend 11 delimiting it, which engages the end of the operating handle 2 and a top piece 12 fitted into the end. Two limit switches 13 and 14 with actuators 15 and 16 are used for automatic stopping of the electric actuator in the end position. The stepped angle piece 17 connected to the sliding plate 5 is
Activating the limit switch 13 in one end position and the limit switch 14 in the other end position. The reducer of the electric motor 6 with a reducer has a
Rotary handle 20 for operating the low voltage switch 1
is installed. All parts mentioned above are covered by a cover 21, with only the rotating handle 20 protruding from the front face 22 of the cover.

Remote control or rotary handle 20 of electric actuator 3
In order to prevent the low voltage switch from being operated inadvertently due to manual operation, the electric actuator 3 is equipped with a locking device, the entirety of which is indicated by 25, and its main feature is a two-arm rotating lever. It is 26. This rotary lever is swingable around a bearing pin 27 mounted on a bearing stand 30. The bearing stand 30 is fixed on the support stand 4 beside the electric motor with a reduction gear so that the rotary lever 26 is arranged in parallel with the electric motor 6 with a reduction gear with a slight distance therebetween. Torsion spring 31
is wound several times around the bearing pin 27, one leg 33 of which is supported on the bearing stand 30 and the other leg 34 is hooked to the rotating lever 26, thereby preventing the rotating lever from interfering with the movable part of the electric actuator. Not pressed into the initial position.

The first arm 35 of the rotary lever 26 is longer than the second arm 36 so that a slight movement will result in blocking. The long arm 35 has a hook-shaped end 37 and its abutment surface 45 so that blocking is achieved with one lock with a thin latch and with three locks with thick latch. is angle piece 1
It engages with the stepped end surface 40 of 7. When the abutment surface is bent or when the shown caulking pin 48 is used, reliable blocking is not hindered even if the rotary lever swings laterally. Said hooked end 3
7 engages with the operator 15 of the limit switch 13 as described above.

The short second arm 36 is provided with an elongated hole 41 for a padlock. The cover 21 has a slit 42 through which the end of the arm 36 passes, the length of which is designed in such a way that the rotary lever 26 reaches the planned locking position.

The locking device 25 described above operates as follows. When attempting to lock the electric actuator 3 against closing of the switch by remote control or manual operation using the rotating handle 20, twist the end of the second arm 36 protruding from the slit 42 of the cover 21. It is lifted against the biasing force of the spring 31 and the rotary lever 26 is swung to a position in which the latch of at least one padlock or similar safety element can be inserted into the hole 41, as indicated by the dash-dotted line in FIG. The padlock is then supported by the wall 43 of the cover 21. The cover 21 receives the resulting load through the bent portion 44 whose bending rigidity is increased to a required value. Furthermore, the cover 21 is firmly fixed to the cover of the switch so as not to shift.

Thus, the hooked end 37 of the first arm has its abutting surface 45 aligned with the stepped end surface 4 of the angle piece 17.
It has moved to a position facing 0 with a small distance between it and 0. As a result, the sliding plate 5 is rotated by the rotating handle 2.
Even if you turn 0, it will not move to the input position. Also at that time, the working surface 4 of the hooked end 37 of the rotary lever 26
6 operates the limit switch 13 by pushing the operator 15 in the same manner as the angle piece 17 of the sliding plate 5 operates during normal operation. At that time, the working surface 4
The shape of 6 is selected in such a way that a constant stroke of the operator 15 can be practically obtained regardless of the number and thickness of the lock latches inserted into the hole 41. To release the lock again, the padlock or other blocking device is removed, and the torsion spring 31 causes the rotary lever 26 to return from the position shown in dashed lines in FIG. 1 to its initial position shown in solid lines. Locking can only be performed when the electric actuator is in the open position of the switch.

Further, as shown in FIGS. 4 and 5, the bearing pedestal 30 of the rotary lever 26 is provided with a folded ear 47 having a slit 50 that corresponds relatively precisely to the thickness of the rotary lever. This slit ensures accurate engagement with the limit switch 13 even when a bearing 27 with a relatively large clearance is used.
The long arm 35 of the rotating lever 26 is guided. As can be seen in the drawing, the slot 50 is arranged intermediate the bearing 27 and the hooked end 37 for this purpose. The closer the slit is to the hooked end, the better the accuracy. However, the position shown provides sufficient guidance.

As can be seen from the figures already described, the rotary lever 26 consists primarily of a flat section. However, if the limit switch for cutting off the circuit of the electric motor is installed in an offset position on the support of the electric actuator, this can be taken into account by the embodiment of the rotary lever according to FIGS. 6 and 7. Ru. The rotary lever 60 shown here also has a support base 6.
1, and is pressed to the initial position by a torsion spring 62. Furthermore, the rotary lever has an abutment surface 64 of its first arm 63 for blocking the sliding plate of the electric actuator, as well as an active surface 65 for actuating the limit switch. However, these are not arranged on the same plane as in the case of the rotary lever 26, but on different planes as shown in FIG. For this purpose, the arm 63 is bent at a right angle by two degrees at its end, and the desired spacing between the respective planes of the abutment surface 64 and the working surface 65 is given by the length of the leg 66. In this case as well, the lateral vibration of the rotary lever is limited by the guide pieces 67 and 68 bent and projected from the support base by pressing. Adaptation to different dimensions of the electric actuator can be easily carried out within the scope of the invention without changing the operation.

[Brief explanation of drawings]

Fig. 1 is a partial side sectional view of a low voltage switch equipped with an electric operating device showing one embodiment of the present invention;
The figure is a plan view of the electric actuator with the cover removed.
FIG. 3 is a sectional view orthogonal to FIG. 1, FIGS. 4 and 5 are a side view and a plan view of a two-arm rotating lever with a bearing stand as a subassembly, and FIGS.
The figures are a side view and a plan view of another embodiment of a two-arm rotary lever with a bearing stand as a subassembly. In the drawings, 1 is a low voltage switch, 2 is its operating handle, 3 is the entire electric operating device, 4 is its support base, 5 is a sliding plate, 6 is an electric motor with a reduction gear, 13 is a limit switch, 15 is its operator, 21 is a cover, 26 is a two-arm rotating lever, 27 is a bearing, 31 is a spring, 35 is a first arm of lever 26, 36 is a second arm thereof, 41 is a hole provided in it, 42 is a slit, 43 is a wall of the cover, 44 its fold; 4
5 is an abutment surface, 46 is an action surface, and 47 and 50 are guide portions.

Claims (1)

[Scope of Claims] 1. An electric operating machine for a low voltage switch, which is equipped with a sliding plate that engages with the operation handle of the low voltage switch and is guided by a support base, and a limit switch for stopping the electric motor at a terminal position. A two-arm rotating lever is swingably supported on a support base, and its first arm rotates around its bearing when the low-voltage switch is opened, and blocks the movement of the sliding plate with its abutment surface. and is capable of swinging on its working surface to drive the operator of the limit switch;
On the other hand, the electric operating device for a low voltage switch is characterized in that a safety element can be attached to the second arm to prevent the two-arm rotating lever from returning to its initial position. 2. An electric operating device for a low-voltage switch, wherein the two-arm rotating lever is pressed to the initial position by a spring in the device according to claim 1. 3. The low pressure device according to claim 1, wherein a guide portion is provided on the support base to act on the two-arm rotating lever from both sides between the bearing and the limit switch. Electric operating device for switches. 4. The device according to claim 1, comprising a cover covering the support and each part mounted thereon, the cover having at least one
a slit for passing the second arm of the two-arm rotary lever with a hole for passing the latch of a padlock; and near the slit, the wall of the cover has a bend. An electric operating device for a low voltage switch, characterized in that it is configured so that it is difficult to bend.