- a base frame for mounting in a switchgear cabinet;

- a sub-frame arranged slidably in an insertion direction in the base frame, which sub-frame houses switching gear;

wherein the sub-frame is positionable in at least a connected position, a test position and a disconnected

position;

- at least one lever hingedly arranged to the sub- frame, wherein the hinge axis is perpendicular to the

insertion direction, wherein a cam is arranged on end of the lever and wherein a handle is provided on the other end of the lever, opposite of the hinge axis;

- at least one cam guide slot arranged in the base frame in a plane perpendicular to the hinge axis, wherein the cam guide slot is for guiding the cam on the lever and has a first slot part extending parallel to the insertion direction and has a second slot part extending perpendicular to the insertion direction.

Such a drawer for a switchgear cabinet is for example known from EP 2826116. This known drawer has a lever with which the drawer can be inserted into a cabinet and can be moved from the disconnected position, along the test position into the connected position.

For an operator it is difficult to determine how far the lever needs to be moved in order to arrive at a desired position. Only the connected position is clear for the

operator, as the lever is then fully moved against the sub- frame . Furthermore, if the drawer is positioned in a disconnected position or the test position and left

unattended, it is possible that an other person inadvertently bumps against the lever and displaces the drawer to one of the other positions.

Accordingly, it is an object of the invention to reduce or even remove the above mentioned disadvantages.

This object is achieved with a drawer according to the preamble, which is characterized by locking means for locking the lever in at least the connected position, the test position and the disconnected position of the sub-frame.

With the locking means it is possible to reliably set the lever in one of the connected position, the test position and the disconnected position. The locking means also ensure that the lever is not inadvertently displaced towards an other position, as the lever first needs to be unlocked to be moved to another position.

In a preferred embodiment of the drawer according to the invention the locking means comprise:

- a latch shiftable arranged on the lever in a direction perpendicular to the hinge axis between a latched position and an unlatched position; and

- a semi-circular disc concentrically arranged on the hinge axis of the lever, wherein at least three notches are arranged in the circumferential edge of the disc for cooperation with the latch in latched position to lock the lever in the connected position, the test position and the disconnected position of the sub-frame. The latch is

preferably spring loaded towards the latched position.

With the semi-circular disc a very cost effective locking means can be achieved in which the different positions can easily be provided by notches in the circumferential edge of the disc.

The latch moves along with the lever, when the lever is moved from one position to another. As soon as the latch arrives at the next notch, the lever falls or is urged by the spring means into the respective notch, locking the lever in the specific position and therefore locking the sub-frame in the respective position.

A further preferred embodiment of the drawer

according to the invention comprises a safety lock arranged on the lever for locking the latch in latched position.

The safety lock provides for an additional safety such that an operator first needs to unlock the safety, before the latch can be moved towards the unlatched position and the lever can be moved to a next position.

This safety lock provides an additional measure to ensure that an operator does not move the latch to another position without thinking.

The safety lock could be rotatable around a rotation axis parallel to the shifting direction of the latch and a part of the safety lock can be moved to coincide with the path of the latch to lock the latch in latched position.

Even further preferred a hole is provided in the lever for mounting of a padlock, which padlock blocks rotation of the safety lock.

If an operator sets for example the drawer in the test position and needs to be sure to no one changes the position of the drawer, then the operator can arrange a padlock into the hole, such that the rotation of the safety lock is blocked and the latch cannot be unlatched.

So, only the one with the key of the padlock then is able to change the position of the drawer.

In yet another embodiment of the drawer according to the invention the base frame comprises on both sides of the sub-frame two cam guide plates, wherein in each cam guide plate a cam guide slot is provided, and on both sides of the sub-frame, adjacent to the cam guide plates, a lever is arranged for engagement with the slots in the cam guide plates .

By providing a lever with cam and a cam guide slot on both sides of the drawer, the chance that the drawer is inadvertently operated is further reduced, as the position of the drawer can only be changed if both lever are

simultaneously unlocked and operated to move the drawer.

An additional advantage that the force for moving the drawer is exerted on both sides reducing the chance that the drawer is skewed in the base frame and the sliding

movement is jamed.

In a further preferred embodiment both cam guide plates are bolted to the remaining base frame. This allows for easy adaptation of existing cabinets. The cam guide plates need to be bolted to an existing cabinet to allow for a drawer according to the invention to be mounted into such an existing cabinet .

In yet a further embodiment of the drawer according to the invention at least a main switch is arranged on the sub-frame, a main latch coupled to the main switch, and an opening arranged in the base frame in which opening the main latch can be moved by rotation of the main switch to block sliding movement of the sub-frame relative to the base frame.

By arranging a main latch to the main switch an addition lock is provided when the drawer is in connected position and the switchgear is turned on by the main switch. Only when the switchgear is turned of, the main latch will disengage from the opening and allow movement of the sub-frame relative to the base frame by suitable operation of the locking means and the lever.

These and other features of the invention will be elucidated in conjunction with the accompanying drawings.

Figure 1 shows a perspective view of an embodiment of the drawer according to the invention. Figures 2A and 2B show a detail of the lever of the embodiment of figure 1 in two positions.

Figure 3A and 3B show the safety lock in more detail of the embodiment of figure 1.

Figure 4A and 4B show the main latch in more detail of the embodiment of figure 1.

Figures 5A - 5D show the lever in four different positions .

Figure 1 shows a perspective view of an embodiment 1 of the drawer. The drawer 1 has a base frame 2 arranged in a cabinet 3. A sub-frame 4 with a front 5 is slidable into the base frame 2.

On both sides of the front 5, levers 6, 7 are arranged rotatable around an hinge axis 8. Each lever 6, 7 has on one end a cam 9 and on the other end a handle 10.

At the base frame 2, on both sides of the sub-frame 4, cam guide plates 11 are arranged, in which a cam guide slot 12 is provided. The cam guide slot 12 has a first slot part 13 extending in the same direction as the sliding direction of the sub-frame 4 and has a second slot part 14 extending perpendicular thereto.

Figures 2A and 2B show the handle 10 of the lever 6 in more detail. A semi-circular disc 15 is arranged

concentrically with the hinge axis 8. Notches 16 are provided in the circumferential edge of the disc 15.

The handle 10 comprises a latch 17 slidable arranged in the length direction of the lever 6. The latch 17 has a protrusion 18, which engages in one of the notches 16.

Figure 2A shows the latch 16 in latched position, locking the lever 6 in one of the desired positions, while figure 2B the latch 16 in unlatched position shows, in which the lever 6 can be rotated.

Figure 3A and 3B show the safety lock 19 in more detail of the embodiment of figure 1. This safety lock 19 is arranged in the handle 10. Figure 3A shows the lever 6 with the latch 17 in unlatched position and the safety lock 19 unlocked .

Figure 3B shows the lever 6 with the latch 17 in latched position and the safety lock 19 rotated over the latch 17, such that movement of the latch 17 is blocked. Only by rotating the safety lock 19 back to the position shown in figure 3A allows for the latch 17 to be moved to the unlatched position .

Figures 4A and 4B show a main latch 20, which is coupled to a main switch 21 of switchgear arranged in the sub- frame 4. At the side of the base frame 2 a plate 22 with a slot 23 is provided.

When the main switch 21 is turned on, as shown in figure 4B, the main latch 20 will be moved into the slot 23 blocking any inadvertent movement of the sub-frame 4 out of the base frame 2.

An additional slot 24 is provided to block movement of the sub-frame 4 when in the test position and with the main switch 21 in the turned on state.

Figure 5A shows the drawer 1 of figure 1 in the insertion position. The lever 6 is arranged and locked in such position, that the cam 9 is aligned with the opening of the cam guide slot 12 allowing for the sub-frame 4 to slide into the base frame.

Figure 5B shows the drawer 1 in the disconnected position. The lever 6 is rotated to the next position in which the lever 6 can be latched by the latch 17 in one of the notches 16 of the disc 15.

In this position, the disconnected position, the cam

9 is just moved in the vertical second part of the slot 12, such that the sub-frame 4 cannot be retracted, but also can not be inserted further into the base frame.

In figure 5C, the lever 6 is rotated further and the cam 9 is moved further into the slot 12, such that the sub- frame 4 is moved further into the base frame. In this position, the switchgear arranged on the drawer 1 can for example be tested.

Figures 5D show the lever 6 in the last position, wherein the drawer 1 is in the connected position. In this position the main latch 20 can lock the sub-frame 4 into the base frame 2.