DE29823122U1 - Plug-in module with active-passive switching - Google Patents

Description

P.6931/SO/Pa

ELMA Electronic AG. CH-8620 Wetzikon (Switzerland)

Plug-in module with active-passive circuit

The invention relates to a module carrier with a plug-in module which can be inserted into a housing by means of guides and which is provided with at least one insertion and removal handle in the form of a lever mounted on an axis on its front side in order to overcome insertion and extraction forces on multiple plugs attached to the rear by &iacgr;&ogr; supporting it on a front housing profile.

WO 96/42187 shows a front system for a printed circuit board with active-passive switching, which senses the insertion position of the printed circuit board via a switching element, regardless of whether a locking has actually occurred. An unintentional failure of a locking mechanism to engage or a shifting of the switching point in the insertion direction can lead to switching states that contradict the mechanical situation.

The object of the invention is to create a secure active-passive circuit for module carriers with plug-in modules. This object is achieved by an additional spring-operated latch being attached to the front for the insertion and removal handle, which inevitably locks the lever in a rear end position of the plug-in module and which, after reaching an effective locking position, actuates a switching element for an active switching of the plug-in module, and that when the latch is pushed down, it causes a passive switching on the switching element before the lever is released by the latch.

This arrangement has the advantage that it monitors the effectiveness of the locking of the insertion and extraction handle. This means that the switching element for the active switching is only activated when the handle lever has been locked, and the electrically active switching element is already switched to passive when the locking mechanism releases the handle lever. Another advantage is when the locking mechanism is accidentally pressed down, since on the one hand a passive switching must already have taken place when the bolt is in the unlocked position, and on the other hand a minimum rotation of the handle lever must take place forwards and backwards before locking can take place again with subsequent activation of the switching element.

A blow to the locked lever also does not cause any bouncing on the switching element, since the bolt is supported independently of the lever in the switching direction of the switching element.

A further advantage is that the spatial arrangement of the lever and latch is so cleverly designed that the spatial and switching requirements of the standards

• IEEE STANDARD 1101.10

• HOT SWAP SPECIFICATION PICMG 2.1 RIO

· VME 64 EXTENSIONS STANDARD VITA 1.1-199X ₁ DRAFT 2.0

are achievable.

Further advantageous embodiments of the invention result from the features of the dependent claims 2 to 12. When the bolt is pressed down, it blocks itself from the locked position into an unlocked position without the active action of other elements and with the rotation of the lever, this blocks the bolt in an unlocking position until it has reached the rear end position again with the plug-in module. The actual locking takes place by force through a spring when the rear end position is reached. This has the advantage that the actuation of the switching element is always carried out by the same

pre-tensioned spring and is unaffected by the speed and impacts when the plug-in module is inserted. Because the latch is guided independently of the lever in a straight guide on the front of the plug-in module, the lever does not have to be moved to reach an unlocking position. The lever can only start turning in the ejection direction when a stop on the latch, which is arranged in the opposite direction to the lever's direction of rotation, has been extended.

The advantages of the mechanical locking can also be exploited without an electrical switching element. For example, a second mirrored

A lever with locking mechanism can be attached to the other end of the front of a plug-in module to make it easier to lever in and out and to simply achieve further locking of the plug-in module in the retracted state. With such an arrangement, additional screwing between the front panel and the housing profile is not necessary, so that only leading centering pins engage on the housing profile to absorb lateral forces.

Because an overlap angle ε is created between the lever and the latch when the unlocking position is reached, by which the lever must be rotated at least before a locked-0 position can be reached again by turning the lever back, it is advantageous if the angle ϕ for the flank change for ejection is larger than the overlap angle ε. This means that the reversal from the unlocked state to the locked state is possible without any movement taking place on the multiple plugs attached to the back of the plug-in module.

The lever and latch are designed in such a way that they can be manufactured using an injection molding process, whereby the essential functional dimensions for mutual engagement are tool-specific dimensions. The manufacturing tolerances are correspondingly small, which ensures a high level of reliability for the function.

The invention is described below using exemplary embodiments. They show:

Fig. 1 Schematic of a section on the lower front side of a

Plug-in module being ejected from the housing of a subrack;

Fig. 2 shows a schematic section through an arrangement in

extended position according to Fig. 1;

Fig. 3 schematically shows the arrangement of Fig. 2 in retracted

Position locked; and

&iacgr;&ogr; Fig. 4 schematically shows the arrangement of Fig. 3 in retracted

Position unlocked.

The figures show a module carrier with a plug-in module 2, which can be moved into and out of a rear end position 10 using an insertion and removal handle 5. An additional spring-operated latch 12 on the front side 7, which automatically secures the insertion and removal handle in the rear end position, activates a switching element 11 for an active switching of the plug-in module after an effective locking position has been reached. Pressing down the latch 12 in the locked state causes a passive switching before the insertion and removal handle 5 is unlocked after a further distance of displacement of the latch and the unlocking is stored mechanically in conjunction with the latch 12.

In Fig. 1, the plug-in module 2 is assembled on its front side 7 as a printed circuit board 2 via fastening elements 38 with a front plate 35. A base 28 is also attached to the front plate 35 at the lower and upper ends, which forms a support body for the switching element 11 and for the lever 6 via an axis 16. In front of the axis 16 and parallel to the front plate, the base 28 is designed as a T-shaped profile, which with its grooves 29 forms a vertical longitudinal guide for the latch 12, which grips the T-shaped profile. The insertion and removal handle 5 is designed as a lever 6

which is rotatably mounted on the base 28 with two lateral tabs over the axis 16 and largely covers the bolt 12 together with the base. On the insertion and removal handle 5 there is a recess 15 through which the bolt 12 protrudes with a projection 32 for its operation. On the bolt 12, in a plane perpendicular to the axis 16, functional elements such as an engagement surface 20, a stop 27 and a laterally formed spring element with an engagement surface 19 are shown, which actuate the switching element 11 in cooperation with the lever 6. The plug-in module can be inserted into guides 3 on the housing 4 at its bottom and top in order to

γ on its back (not shown here) to establish a connection via multiple plugs. A leading contact pin 33 is attached to the base 28 in order to achieve earthing of the plug-in module before the multiple plugs are operated. The switching element 11 is designed as a microswitch with plug contacts in order to be able to connect it to the printed circuit board 37. The housing ends towards the front 7 as a housing profile 8 with recesses 36 in which the lever 6 can engage in order to overcome the clamping forces on the multiple plugs on the back more easily when pushed in by its reduction.

The other figures 2 to 4 are provided with the same reference symbols and represent different switching situations, with the latch 12 and lever 6 being cut in the previously mentioned plane for the functional elements. Fig. 2 shows the position when lifting out the plug-in assembly in which the rotation of the lever 6 by an angle α has caused a lifting by a lifting distance 34 with a value of, for example, 6.5 mm, and to continue the movement, the plug-in assembly is pulled out on the levers 6 without rotation.

In the same angle of rotation position α, the plug-in module must be inserted so that the protruding lugs of the lever 6 can enter the recesses 36 on the housing profile 8. In this situation, the latch 12 is pressed upwards along the guide grooves 29 by a return spring 24 and rests with the circular engagement surface 20 on a likewise circular guide surface 21 of the lever with radius 31. The vertical position of the latch 12 corresponds to

an unlocking division 13, which remains unchanged when the lever is rotated, since both circular surfaces 20, 21 coincide in their center with that of the axis 12. When the lever 6 is rotated back by the angle α, an inclined shoulder 18 with an overlap of a height h, which can be, for example, 1 mm, is brought up to contact with a leaf spring 17. In this position, the guide surface 21 still covers parts of the engagement surface 20 and prevents the latch 12 from being pushed upwards by the return spring 18.

Only after further rotation by an angular amount ε is the latch 12 γγ released and at the same time the leaf spring 17 is bent back by this amount. The return spring 24 is designed in such a way that it safely overcomes the friction of the latch 12 on the base 28 and on the lever 6 as well as the switching force of a cam 23 against the switching element 11 in order to reach the position according to Fig. 3. A stop 27 on the latch 12 prevents the lever 6 from turning back despite the pre-tensioned leaf spring. The movement sequence triggered by the return spring initially provides that the lever 6 is locked, that the cam 23 then actuates the switching element at a safety distance and that when the latch 12 is fully retracted, the tip of the leaf spring 17 on the inclined surface 18 of the lever is bent by an angular amount ε can slide back into its relaxed position. This position shown in Fig. 3 is inevitably reached by turning the lever 6 and corresponds to the final state when the plug-in module is inserted.

From this locked final state, the plug-in assembly is lifted out by first pressing down the latch 12 on the projection 32. The downward-moving cam 23 leaves the microswitch and triggers the passive switching of the plug-in assembly, while a rotary movement of the lever 6 is still blocked by the stop 27 on the latch. While the latch 12 is moving downwards, the leaf spring is pre-tensioned by an angle ε on the inclined surface 18 of the lever, by which it springs back as soon as its tip is released from the inclined surface 18. The springing back creates an overlap between an engagement surface 19 and the guide surface 21.

and the unlocked state of Fig. 4 is created, from which the lever 6 can be rotated and as the overlap between the engagement surface 19 and the guide surface 21 decreases, a new overlap between the guide surface 21 and the engagement surface 20 is built up. As soon as the engagement surface 19 of the leaf spring is left, the latch is pushed from an unlocking pitch 14 by the height "h" into the unlocking position, in which the circular engagement surface 20 and the guide surface 21 touch. The further the guide surface 21 slides down the engagement surface 20 with the rotation of the lever 6, the greater the normal force between these two surfaces and thus also the friction force with a constant spring force, so that the lever 6 is held in this angular position by the greatest friction force when an angle α is reached as in Fig. 2. This has the advantage that the lever 6 does not fall down despite its own weight even in a mirrored arrangement on the upper front side, but can be maintained in the position specified by the angle α, which is determined by the lever 6 striking the base 28.

A further advantage is that the active or passive circuit of the plug-in module is also visible externally through the locked or unlocked position of the latch.

It is understood that the locking mechanism shown here, which is indicated externally by the position of the projection 32, can also be used without switching element 11 and generally outside the cited standards for a visually or tactilely controllable locking mechanism.

Summary

The figures show a module carrier with a plug-in module (2) which can be moved into and out of a rear end position (10) using an insertion and removal handle (5). An additional spring-operated latch (12) on the front side (7), which automatically secures the insertion and removal handle in the rear end position, activates a switching element (11) for an active switching of the plug-in module after an effective locking position has been reached. Pressing down the latch (12) causes a passive switching in the locked state before the insertion and removal handle (5) is unlocked after the latch has moved a further distance and the unlocking is stored mechanically in conjunction with the latch (12).

(Figure 3)

Claims (12)

Protection claims 1. Module carrier with a plug-in module (2) which can be inserted into a housing (4) by means of guides (3) and which is provided with at least one insertion and removal handle (5) in the form of a lever (6) mounted on an axis (16) on its front side (7) in order to overcome insertion and removal forces on multiple plugs attached to the rear by supporting it on a front housing profile (8), characterized in that for the insertion and &iacgr;&ogr; Extractor handle (5) an additional spring-operated latch (12) on the Front side (7) is attached, which inevitably locks the lever in a rear end position (10) of the plug-in module and which, after reaching an effective locking position, actuates a switching element (11) for an active switching of the plug-in module (2), and that when the latch (12) is pushed down, this causes a passive switching on the switching element (11) before the lever (6) is released by the latch. 2. Module carrier with a plug-in module according to claim 1, characterized in that after unlocking the lever (6), locking of the lever is only possible if the lever (6) is rotated at least by an angle α > ε in the extension direction and back again into the rear end position (10), the angle ε representing an overlap with which the latch (12) blocks itself in the unlocking position (14) on a guide surface (21) of the lever (6), while when the lever (6) is rotated by an angle α > ε and back, the latch (12) is held by the guide surface (21) in a further unlocking position (13). 3. Module carrier with a plug-in module according to claim 1 or 2, characterized in that the unlocking is primarily stored by a spring element (22) attached to the latch (12), which when the latch (12) is pressed down on an inclined shoulder (18) of the Lever (6) can be deflected by the angle ε against the ejection direction of the lever in order to spring back into a position with an overlap in the size of the angle ε after leaving the inclined shoulder (18). 4. Subrack with a plug-in module according to claim 3, characterized in that a leaf spring (17) is provided as the spring element (22) and that the leaf spring (17) and latch (12) have engagement surfaces (19, 20) which can be placed on a guide surface (21) of the lever (6) which can pivot about the axis (16), wherein the engagement surface (19) of the spring element (22) is further away from the the axis (16) than the engagement surface (20) of the latch (12). 5. Module carrier with a plug-in module according to one of claims 1 to 4, characterized in that the latch (12) has a cam (23) for actuating the switching element (11), which can be displaced transversely to the switching direction of the switching element (11). 6. Module carrier with a plug-in module according to one of claims 1 to 5, characterized in that the electrical switching element (11) is an electrical microswitch. 7. Module carrier with a plug-in module according to one of claims 1 to 6, characterized in that the latch (12) is provided with a stationary restoring spring (24) opposite to its downward pressing direction. 8. Subrack with a plug-in module according to one of claims 1 to 8, characterized in that the plug-in module (2) has a further, mechanically identical locking mechanism but without a switching element (11) in order to be able to dispense with additional mechanical securing elements such as fastening screws. -10-' 9. Subrack with a plug-in module according to claim 8, characterized in that centering pins (25) protruding in the insertion direction are attached to the front of the plug-in module, which align the plug-in module (2) at the front in matching holes (26) on the front housing profile (8). 10. Subrack with a plug-in module according to one of claims 1 to 9, characterized in that the overlap angle ε is smaller than the angle φ for the flank change on the handle lever (6) between the end of the insertion into the rear end position (10) and the start of the ejection of the plug-in module (2) in the opposite direction. 11. Module carrier with a plug-in module according to one of claims 1 to 10, characterized in that the lever (6) and latch (12) are each manufactured in an injection mold in order to keep the dispersion of the functional mass for locking and unlocking small. 12. Module carrier with a plug-in module according to one of claims 1 to 11, characterized in that the space required for the lever (6) and the latch (12) lies within the dimensions of the IEEE STANDARD 1101.10 permitted for the insertion and removal handle (5).