GB2149972A - Hand-operated device for an electric switch - Google Patents

Abstract

An operating device for a hand-operated electric switch (1) with a rotatable operating shaft includes an operating handle (3) and a member (4) for switch position indication which can be fixed relative to the electric switch. Prior to being mounted on the electric switch, the operating handle (3) and the indicating member (4) are locked in relation to each other, by means of a locking device, in the position where the indicating member shows the open position of the switch. Upon installation to the electric switch, this locking device is released automatically. The operating device can be mounted with the indicating member (4) oriented in one and the same clock position independent of the mounting position of the electric switch. The operating handle can include a spring-loaded locking slide (5) for locking the operating handle in the closed or open position. <IMAGE>

Description

SPECIFICATION Hand-operated device for an electric switch The present invention relates to an operating device for a hand-operated electric switch with a rotatable operating shaft, for example a low voltage load switch or a low voltage safety switch. The operating device comprises an operating handle and a member for switch position indication which can be fixed relative to the electric switch, said member being referred to herein as the "indicator".

To simplify the electrical connection of, for example, a load switch in a switchgear enclosure, there is a need to be able to mount the load switch in any one of four different positions depending on whether the connection conductors leading from the supply network arrive at the switch from above, from below, from the right, or from the left. On the other hand, as regards the operating device of the switch, for various reasons, in particular in a plant with a plurality of hand-operated electric switches with the same type of operating device, it is highly desirable that the operating devices should always be installed with the indicator in a definite angular position (relative to a clock face), for example such that the open position indication for all the operating devices is obliquely upwards to the right (i.e.

in hour hand position corresponding to one thirty).

One aim of the present invention is to provide an operating device with a built-in locking means which, upon mounting of the operating device on an electric switch, and in different angular positions relative thereto, makes it impossible to have an incorrect indication of the contact position. In addition, the operating device should be designed so that it may be locked in a simple manner in the closed position or in the open position, so that interlocks can be arranged in a simple manner between the electric switch and a door of the enclosure and between two adjacently mounted electric switches, and so that two electric switches can be mechanically connected in parallel in a simple manner. This is achieved according to the invention with an operating device as defined in the following claim 1.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, wherein Figure 1 shows, in perspective, a load switch mounted in an enclosure with an operating device according to the present invention, the switch being in the open position, Figures 2 and 3 show a front view of the operating device of Figure 1 with the indicator showing the open and the closed position, respectively, Figure 4 corresponds to Figure 2 but with a modified indicator, Figures 5 and 6 show the central operating unit of the operating device of Figure 1 viewed from below (Figure 5) and in partial section from the side in the direction of the arrow VI in Figure 5 (Figure 6), Figures 7, 8 and 9 show an operating handle included in the device of Figure 1 viewed from the front (Figure 7), from the back (Figure 8) and, in the direction of the arrow IX in Figure 7, from the side (Figure 9), Figures 10, 11 and 1 2 show an indicator plate included in the device of Figure 1 viewed from the front (Figure 10), from the back (Figure 11) and, in the direction of the arrow XII in Figure 10, from the side (Figure 12), Figure 1 3 shows in side view a locking slide included in the device, Figures 1 4 and 1 5 show a handle bearing belonging to the operating device viewed from the front (Figure 14) and in section (Figure 15) along the line XV-XV in Figure 14, Figures 1 6 and 1 7 show an extension shaft with a shaft coupling for the operating device viewed from the front (Figure 1 6) and, in the direction of the arrow XVII in Figure 16, from the side (Figure 17), Figures 1 8 and 1 9 show an interlocking sleeve intended to be mounted on the extension shaft viewed from the side (Figure 18) and in cross-section (Figure 1 9) along the line XIX-XIX in Figure 18, Figure 20 shows, in perspective, that part of the operating device which is mounted on an enclosure door, provided with an interlocking device for interlocking the door when the electric switch is in the closed position, Figure 21 shows, in perspective, two adjacent load switches with interlocking devices preventing the switches from both being in the closed position at the same time, and Figure 22 shows a front view of two adjacent load switches which are parallel-connected mechanically.

Figure 1 shows a load switch 1 for a rated voltage of at the most 1000 V mounted behind an enclosure door 2 and provided with a hand-operated operating device according to the present invention. The switch 1 is designed so that closing and opening of the switch contacts take place by a 90' rotation of a square crosssection operating shaft.

The operating device comprises an operating handle 3 provided with a locking slide 5, the handle being axially fixed to an indicating plate 4. This plate, called herein the "indicator", is in turn fixed to a handle bearing 6 screwed to the enclosure door 2. Between the operating handle 3 and the switch 1, there extends an extension shaft 8 which is fixed to a shaft coupling 7, which by way of a second indicating plate 4a is attached to the casing of the switch 1. On its end facing the operating handle 3, the extension shaft 8 is provided with an interlocking sleeve 9 (Figures 18 and 19). The parts 3, 4, 5, 6 and 7 are suitably made of an electrically insulating plastics material.

The operating handle 3, the indicator 4 and the locking slide 5 form an operating unit, which is shown in its assembled state in Figures 2, 3, 5 and 6. This unit is intended to be supplied separately and can be mounted in a simple manner on the switch 1 or the handle bearing 6 without the use of tools. The indicator 4 has a forwardly-facing indicating ring 41 (Figure 1 0) with distinctive markings in, for example, black on a white background, for the two contact positions of the switch as well as for the only possible direction of rotation available from each contact position.

The operating handle 3 is constructed with a hand grip 21 and a cover plate 22 with two diametrically located indicating holes 23 through which the markings on the ring 41 are visible. Figures 2 and 3 show a front view of the operating unit 3, 4, 5, when the switch contacts are in their open position (Figure 2) and when they are in their closed position (Figure 3).

Figure 4 shows the operating unit 3, 4, 5 with a different form of contact position indication, the.unit being shown in the open position of the switch contacts. For example, by making the operating handle 3 black and the locking slide 5 white, the latter may serve as a pointer and cooperate with an indicating plate 10, fixed below the indicator 4, and provided with markings for the closed and open positions of the switch.

The assembly of the operating handle 3 and the indicator 4 is carried out as follows: The operating handle and the indicator are brought together axially after such a relative rotation of one to the other that a locking cam 24, which is arranged on a rearwardly-directed central pin 25 on the handle 3, is able to pass by a corresponding locking cam 44 in the central opening of the indicator 4. Thereafter, the operating handle is rotated in a counterclockwise direction, to cause the locking cam 24 to enter into locking engagement behind the cam 44 and lock the parts 3, 4 to each other in the axial direction. After a rotation of, in total, 270 , a locking projection 26 on the handle 3 contacts a corresponding locking projection 46 in the indicator 4 and prevents a continued counterclockwise rotation.In this position, a resilient locking tongue 47 on the indicator also engages with a locking recess 27 on the handle, so that clockwise rotation of the handle is also prevented. The two parts 3, 4 are thus locked in relation to each other, and the indicator 4 shows the position indication for the open position.

The rear part of the shaft coupling 7 is constructed in the same way as the corresponding part of the operating handle 3, and therefore the fixing of the shaft coupling to the associated indicator 4a is also effected as described above.

In so far as the attachment of the indicator 4a is concerned, the casing of the electric switch 1 is designed in the same way as the handle bearing 6, and therefore only the attachment parts of the latter are shown in the drawings. In the ensuing description of how a handle/ indicator unit 3, 4 or a shaft coupling/indicator unit 7, 4a is to be mounted on the electric switch, reference is therefore made to Figure 14 which shows the handle bearing. In order to separate, in the description, the attachment parts of the electric switch casing from the corresponding parts of the handle bearing, however, the reference numerals for the first-mentioned part are apostrophized in the text of the description.

In a plant including a plurality of handoperated electric switches all having the same type of operating device, in order to obtain a uniform front view, as mentioned above, the operating devices should always be mounted with their respective indicator in a definite position in relation to the vertical and horizon tal planes through the longitudinal axis of the respective operating device, for example such that the open position indication of the indicator lies at the upper right.In view of this fact, when mounting a handle/indicator unit 3, 4 on an electric switch (or a shaft coupling/indicator unit 7, 4a when the operating handle is mounted on an enclosure door), the following operations are carried out: The operating handle 3 with the indicator 4, which are locked to each other in the open position prior to mounting, are oriented in the desired final angular position for the indicator and are pushed onto the operating shaft until a stop position is reached. Thereafter, the entire unit 3, 4 is rotated through 45 in a clockwise direction and is pressed further to a new stop position, causing three radial locking projections 42 on the indicator to enter into corresponding slots 61' in the electric switch casing (which, as mentioned above, has mounting parts similar to those of the handle bearing according to Figure 14). Thereafter the entire unit is rotated in the counterclockwise direction, causing the projections 42 to enter behind the cams 62' on the electric switch casing and fix the handle/indicator unit in the axial direction (i.e. a sort of bayonet connection is achieved).

After a 45 rotation in the counterclockwise direction, a resilient locking tongue 43 on the indicator snaps into one of the recesses 63' adapted therefor in the electric switch casing, the indicator thus being locked against rotation. During the rotation in the counterclockwise direction, a locking tongue 47 of the indicator slides up on one of the cams 62' and is thereby pressed out of its locking engagement with the operating handle, which can thus be rotated in the clockwise direction for closing the switch.

If, during the mounting of the handle/indicator unit, it is not possible to rotate the operating shaft in the clockwise direction, this means that the switch is in the closed position. It is then necessary, before the handle/indicator unit is pushed into the shaft, to orient the unit in an angular position which is displaced through 90 in the clockwise direction past the desired final position of the indicator. After the unit has been pushed onto the shaft, the entire unit is rotated through 45 in the counterclockwise direction and is pressed to the stop position.

Thereafter, the unit is rotated through a further 45 in the counterclockwise direction, whereby the switch is disconnected and the indicator is fixed to the electric switch casing both axially through the bayonet socket 42, 62' and against rotation through the locking tongue 43. At the same time, the locking of the operating handle in the clockwise direction is released, thus enabling a closing of the electric switch.

When mounting a handle/indicator unit 3, 4 on a handle bearing 6 screwed to an enclosure door, the unit is inserted into the bayonet socket of the handle bearing in an angular position which is displaced 45 in the clockwise direction past the intended final position of the indicator. Thereafter, the unit is rotated through 45 in the counterclockwise direction until the locking tongue 43 on the indicator snaps into one of the recesses 63 in the handle bearing.

The extension shaft 8 (Figures 16, 1 7) and the interlocking sleeve 9 (Figures 18, 19) mounted on the shaft are designed in such a way (a square cross-section with truncated corners) that agreement as to position always prevails between the shaft coupling mounted on the electric switch and the operating handle mounted on the enclosure door.

To prevent the operating handle 3 from being removed when the enclosure door is open, the indicator is provided with a resilient locking tongue 48, which during a 45 rotation of the handle in the counterclockwise direction past the closed-position indication, is locked against an edge 28 of the central pin 25 of the handle.

To capture the interlocking sleeve 9 mounted on the front end of the extension shaft when the enclosure door is closed, the handle bearing 6 is provided with guiding legs 64 (Figure 1 5) forming a funnel-shaped extension in the rearward direction.

A hand grip 21 of the operating handle has a recess 29, in which the locking slide 5 is displaceable against the action of two springs 11 (Figure 6). As will be clear from Figure 13, the locking slide is formed with two legs 57, which, when the slide is pressed into the indicator are pushed into diametrically located locking slots 49 and 50, respectively, in the indicator, the operating device thus being locked in the closed or the open position. The slide can be locked in its locking position with the aid of a padlock, the shackle of which is hooked into two holes 30 provided therefor in the hand grip 21. In its free position, the slide is fixed in the hand grip with the aid of a locking shoulder 58 arranged on the slide, the locking shoulder making contact, under spring pressure, with the front edge of one of the holes 30.

To prevent the enclosure door 2 from being opened when a switch 1 located behind it is in its closed position, a spring-loaded interlocking slide is provided in the handle bearing 6. This slide enters into a surrounding slot 91 in the interlocking sleeve 9 (Figures 18, 19) mounted on the extension shaft 8. Over part of its circumference, this slot is open towards the forwardly-facing end of the sleeve so that interlocking does not occur when the switch is in its open position.

In certain cases there is a need to be able to open the door even if a switch is in its closed position. To enable an authorized person to do so, it is possible to install a locking device 66 (Figure 20) in a knock-out opening 65 (Figure 15), arranged in the handle bearing, for overriding the door interlock. As an alternative, a possibility for interlock override by means of a screw driver can be provided.

Figure 21 shows two juxtaposed switches 1 with an interlocking rod 1 2 extending between the switches, this rod preventing the switches from each being in their closed position at the same time. For this purpose the indicator 4 is provided with radial slots 51 (Figure 11), into which such a rod can be inserted. Adjacent the slots there are arranged fixing tongues 52 for fixing sheet metal angles (not shown) for guiding the respective rod. In all positions other than the open position of the switch, the slots 51 are locked by means of a blocking ring 31 arranged on the operating handle. This ring is provided with recesses 32, which in the open position of the operating device are situated just opposite the slots 51 and leave these slots free.

When both switches are in the open position, the rod 1 2 may be pushed manually into the slot 51 of one of the operating devices of the switch to block that operating device while releasing the other switch so it can be switched on.

Figure 22 shows how two juxtaposed switches 1 may be connected together mechanically in parallel by means of two parallel rods 1 3. These rods extend between attachments 14, which are rotatably journalled in recesses 33 in the respective operating handles 3.

The invention is not limited to the embodiment shown, since several modifications are feasible within the scope of the following claims. For example, the operating handle need not be designed in the manner shown, but may, particularly for larger switches, be designed with a larger handle, for example in the form of a square wheel which is attached to the corners of the cover plate 22 by means of four inwardly-extending oblique spokes.

The hand grip 21 shown in the drawing is thereby formed solely to serve as a bearing for the locking slide 5.

Claims (11)

1. An operating device for a hand-operated electric switch with a rotatable operating shaft, which operating device comprises an operating handle and an indicator (as herein before defined) which can be fixed relative to the electric switch, characterized in that the operating handle and the indicator form an operating unit which includes a first locking device for mutual fixing of the handle and the indicator in the axial direction as well as a second locking device which, prior to a connecting of the unit to an electric switch, locks the handle and the indicator mutually in positions in which the operating unit indicates the open position of the switch but which, when being mounted on the electric switch, is automatically released.

2. An operating device according to claim 1, in which the indicator comprises a plate with markings for contact position and/or direction of rotation, and the operating handle is formed with a cover plate with indicating holes, through which the markings of the indicator plate are visible.

3. An operating device according to claim 1 or 2, in which the operating unit formed by the operating handle and the indicator includes a third locking device, which is arranged to prevent any relative rotation between the handle and the indicator beyond that indicating the open position of the switch.

4. An operating device according to any preceding claim, in which the operating handle includes a locking slide arranged for locking the electric switch in the closed or in the open position, the locking slide being displaceable against the action of a spring member to a locking position, in which the slide is in engagement with the indicator, and in which the operating handle is provided with holes for the lockable fixation of the slide in the locking position.

5. An operating device according to any of the preceding claims, in which the indicator is provided with a resilient locking tongue arranged to enter into locking engagement with a corresponding recess in the switch casing and the handle bearing, respectively, for locking the indicator against rotation.

6. An operating device according to any of the preceding claims, in which the indicator is axially fixed on a casing of the switch and on the handle bearing, respectively, through a bayonet socket provided with radial locking projections arranged on the indicator and corresponding slots and locking shoulders arranged in the switch casing and the handle bearing, respectively, the second locking device being adapted to be released by the effect of such a locking shoulder under rotation of the indicator to its fixed position.

7. An operating device according to any of the preceding claims, in which the operating unit. consisting of the handle and the indicator, is mounted on a handle bearing mounted on a door of an enclosure, an extension shaft being arranged between the operating handle and a shaft coupling fixed to the electric switch via a second indicator.

8. An operating device according to claim 7, in which the handle bearing includes a spring-loaded interlocking slide for interlocking the electric switch to the door, the interlocking slide entering a surrounding slot in an interlocking sleeve mounted on the extension shaft, part of the circumference of the slot being open towards the forwardly-facing end of the sleeve so that the interlocking is released when the electric switch is in its open position, and in which the handle bearing is provided with a knock-out opening for the possible installation of a locking device for overriding the door interlock.

9. An operating device according to any of the preceding claims,in which the indicator is provided with at least one radial slot for an interlocking rod extending between the operating devices of two adjacent electric switches, the operating handle being provided with a blocking ring having recesses, the blocking ring being so arranged that the slot is left free only when the respective electric switch is in its open position.

1 0. An operating device according to any of the preceding claims, in which the operating handle is provided with recesses for mounting therein members serving to mechanically connect two electric switches mounted next to each other.

11. An operating device for a hand-operated electric switch substantially as hereinbefore described with reference to the accompanying drawings.