Relay and component module combination

A relay and control module combination wherein the control module has an essentially cuboid housing with a coupling side for plug connection to an auxiliary connection side of a cuboid relay housing. Mutually complementary plug connector elements, which can be connected mechanically and electrically, are provided in both the coupling side and in the auxiliary connection side, The plug connector elements allow mechanical and electrical coupling between the control module and the relay. In this way, a universal relay can be converted into a special relay having a specific function by plugging on the control module.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to an arrangement of a relay and control
 module combination wherein the relay has an approximately cuboid housing
 with a main connection side from which load connecting elements emerge and
 with an auxiliary connection side with control connections. The the
 control module has a module housing with a coupling side which can be
 fitted to the auxiliary connection side of the relay housing and, in the
 region of the coupling side to the control connections, has complementary
 plug connections which produce an electrical connection of the control
 module for the relay.
 2. Description of the Prior Art
 Electrical and electronic circuits which are arranged separately from the
 relay, for example on a printed circuit board, are widely used for
 actuating and monitoring electromagnetic relays. It is often desirable to
 combine the relay with its actuation circuit, in which case it is also
 known for an electronic circuit to be accommodated in the relay housing
 itself. However, such a relay with a built-in electronic circuit is more
 complex and more expensive and, owing to the special circuitry, can be
 used only for specific purposes. In addition, the required quantities for
 such designs are typically relatively low. It is also known for an
 electronic module to be produced for a relay as a separate module and, if
 required, to be accommodated in an appropriate chamber in the relay
 housing (DE 36 14 919 A1). The electrical coupling between the electronic
 module and the relay is, in this case, produced externally via a printed
 circuit board or the like.
 Furthermore, it is also known for a plug-in relay and an additional module
 to be connected via their respective housings to form a unit (EP 05 07 729
 A2). In this case, however, the electrical coupling of the additional
 module to the relay is once again produced only via the respective
 connecting pins and via a common relay socket. In contrast, the housings
 are connected to one another mechanically. On the other hand, relays have
 also been disclosed (EP 0409 613 A2) which have connecting pins on various
 housing sides in order, for example, to carry out the actuation via a
 solder side of a printed circuit board while the load connections are
 coupled via blade plugs.
 FR-A1-26 96 040 discloses an interrupter switch whose design corresponds to
 the relay construction mentioned initially. There, however, the load
 connecting elements are not connected to a main connection side until
 additional modules have been fitted. As a result, the multi-part housing
 has openings on all sides which is unacceptable for a relay subject to
 relatively stringent requirements for insulation and electric-shock
 protection. A control module in the form of a heat protection relay is
 likewise schematically indicated, without any matching of the respective
 housing shapes being evident.
 The aim of the present invention is to provide an arrangement of a relay
 with a control module of the type mentioned at the beginning, wherein the
 module can be coupled, as required, to the relay. In addition, the module
 forms not only a mechanical unit with the relay, but also an electrical
 unit; the relay also capable of being operated normally without the
 control module.
 SUMMARY OF THE INVENTION
 According to the present invention, this aim is achieved in that the module
 housing is cuboid in shape, wherein the module housing and the auxiliary
 connection side of the relay housing on the coupling side of the module
 housing have identical areas and are matched to one another in such a
 manner that, once the two housings have been plugged onto one another,
 they form an approximately cuboid combination housing.
 On its housing, the control module of the present invention has a coupling
 side with plug elements by means of which it can be plugged onto a
 corresponding relay housing which has an auxiliary connection side with
 corresponding control plug connections. Since the relay itself invariably
 has a main connection side via which coil connections can be connected,
 the control module could be operated on its own with the plug connections
 of its coupling side toward the relay. However, in addition to its
 coupling side, the control module preferably also has a further module
 connection side with external connections. In this case, particularly good
 electrical isolation of all the control and test connections from the load
 connections of the relay is possible.
 The control module according to the present invention, which can be plugged
 on, allows the use of a relay designed for universal purposes both with
 and without this control module. As such, it is feasible for the relay to
 contain only additional connecting elements in a cap, with all the
 functional elements having a completely identical design. In this case, it
 is possible to produce either a normal relay without additional control or
 a relay which can be combined with the control module; for example, by
 replacing the cap. Plugging the control module on connects the two
 housings not only electrically but also mechanically. In order to
 reinforce this mechanical connection, latching elements which engage one
 another can be provided on both housings. Furthermore, the housing gap
 between the relay housing on the one side and the module housing on the
 other side can be sealed.
 Additional features and advantages of the present invention are described
 in, and will be apparent from, the Detailed Description of the Preferred
 Embodiments and the Drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 FIG. 1 shows a control module 10 with a module housing 11, which can be
 joined together with a relay 20 and its relay housing 21 to form a relay
 module 30 with a combination housing 31. The control module 10 has an
 essentially cuboid housing 11 which, additionally, has an integrally
 formed plug collar 13 on its underneath or module connection side 12. This
 plug collar 13 encloses connecting elements which cannot be seen; for
 example, blade plugs or round plugs. Furthermore, the housing 11 forms a
 coupling side 14 in which plug openings (which cannot be seen) with plug
 sockets are provided. These are provided for mechanical and electrical
 connection to the blade plugs of the relay 20, which are still to be
 described. Furthermore, a latching hook 15 is, in each case, integrally
 formed to the side of the coupling side 14. A fastening lug 16, for
 example, is integrally formed on the opposite side.
 The relay housing 21 is likewise substantially cuboid in shape. On its
 underneath or main connection side 22, it has two chambers 23 in which
 load connecting elements 24 for high currents, for example 150 A, and
 which pass out of the relay interior are arranged. The leads can be
 connected, for example, via screw terminals. In order to achieve complete
 isolation between the load connections and the control connections, the
 latter are not passed to the outside on the main connection side but on an
 auxiliary connection side 25 of the housing 21, which is at right angles
 to the main connection side. In the present example, there are two coil
 connections 26 and two additional load connections 27 via which, however,
 only relatively low currents, for example of a maximum 5 A, can be
 carried. These additional load connections 27 are used, for example, to
 measure the load current in the additional control module 10. Latching
 recesses 28 corresponding to the latching hooks 15 on the control module
 10 are formed to the side of the auxiliary connection side 25.
 Furthermore, a circumferential sealing collar 29 is arranged on the
 auxiliary connection side 25 and is, for example, molded from an elastomer
 material.
 The internal construction of the relay 20 is irrelevant here. It may, in
 this case, be a conventional electromagnetic system, in which case the
 load connections 24 and 27 as well as the coil connections 26 are passed
 out in the illustrated manner by an appropriate physical design. The
 connections 26 and 27 are expediently mounted in the cap itself, wherein,
 in a preferred embodiment, their coupling to the coil connections on the
 one side of the relay and the load connections on the other side of the
 relay can be produced by plugging on the cap.
 The control module 10 likewise may have any required internal design.
 Depending on the application, this control module 10 contains an
 electronic control circuit for actuating the electromagnet system in
 accordance with specific conditions, for example as a time controller, as
 a battery isolating circuit on the basis of specific requirements, as a
 load-current monitor or in order to reduce the coil power when the relay
 is held on. The control module 10 may also contain a diagnostic
 capability.
 When the module housing 11 is plugged onto the relay housing 21, a
 combination housing 31 is produced as shown in FIG. 2; this itself being
 essentially cuboid in shape. The coupling joint 32 between the two
 individual housings is closed so that it is washproof by the sealing
 collar 29, so that the plug connections 26 and 27, together with the plug
 sockets (which are not illustrated) in the module housing 11, are
 protected. An appropriate arrangement of the main connection side 33 and
 of the auxiliary connection side 25 on the relay housing 21 on the one
 hand, as well as the module connection side 12 and the coupling side 14 of
 the module housing 11 on the other hand, results in a common connection
 side 33 from which both the load connections 24 as well as the module
 connections (which cannot be seen) in the plug collar 13 emerge.
 Although the present invention has been described with reference to
 specific embodiments, those of skill in the art will recognize that
 changes may be made thereto without departing from the spirit and scope of
 the invention as set forth in the hereafter appended claims.