GB2254189A - Mounting of electrical devices - Google Patents

Abstract

Electrical devices such as miniature circuit breakers (1) are detachably mounted to a rail. The rail has a pair of spaced and opposed outwardly turned flanges (10) and an abutment (16) spaced from the flanges in the same longitudinal direction as the flanges are spaced apart. The electrical device to be mounted on the rail has a lip (4) arranged to cooperate with one flange (10) and a slide member (7) which engages with the other flange. The abutment (16) and slide member (7) cooperate to urge the slide member towards an engaged position on movement of the device (1) toward the abutment. <IMAGE>

Description

MOUNTING OF ELECTRICAL DEVICES This invention relates to the mounting of electrical devices such as, for example, circuit breakers and other circuit protection devices and is particularly concerned with the mounting of such electrical devices in a releasable manner on a rail or like support.

An example of such electrical device is a circuit breaker sold by M.K. Electric Limited under catalogue number 5906 (MK is a registered Trade .Mark) or the circuit breaker shown in British Patent No. 2119576B. Such circuit breakers are nown as miniature circuit breakers (MCB's) and comply with British Standard BS 3871. Such MCB's and other devices such as Residual Current Circuit Breakers and Time Delay Switches are commonly mounted on a standard rail which may be in a consumer unit. One form of this rail is shaped as a shallow "U" with outwardly turned flanges and is commonly called a "DIN rail".

DIN rail mounted devices are provided with a recess on a face which will be referred to for convenience as the "lower face" although it could equally be an end face depending on the orientation of the DIN rail. The lower face has an undercut portion or lip facing into the recess which is arranged to co-operate with one outwardly turned flange of the DIN rail and a slide member which may be moved between two positions in one of which it serves to hold the device to the rail by engaging the underside of the opposing outwardly turned flange and in the other of which it is disengaged and clear of the rail. The slide member may be arranged so that it is urged into the first engaged position by a spring or may be arranged so that it remains in either position by a detent mechanism to prevent it remaining in an intermediate position.In either case, the slide member is normally provided with a detail on the outer end so that a tool such as a screwdriver can be inserted to move the slide member into the engaged or disengaged position to permit installation or removal. However access to the slide member by means of a screwdriver is frequently difficult and may be dangerous due to the proximity of electrical conductors.

An object of the present invention is to s1mpiify installation or removal of DIN rail mounted devices and in particular eleminate the need for a tool for the purpose.

According to the present invention an electrical device mounting arrangement comprises a rail having a pair of opposed outwardly turned flanges spaced apart in a longitudinal direction and an abutment spaced from the flanges in the same longitudinal direction, the rail being arranged to cooperate with a rail mounted electrical device having means to engage one said flange and a slide member to engage the outer said flange, the abutment being arranged to co-operate with the slide member to urge it towards the engaged position on movement of the electrical device toward the abutment.

A detent and two detent receiving recesses or two detents and single detent receiving recess may be provided to locate the slide member in the engaged and disengaged positions. Suitably arranged the detent or detents assist the movements of the slide member initiated by the abutment toward the fully engaged position and inward position so that the electrical device is fully secured to the rail by the engagement means under the other flange of the rail. In order to remove the device pressure on the device away from the abutment causes the rail flange nearest the abutment to urge the slide member outwardly so that the engagement means, suitably a lip on the device, disengages from the rail flange furthest from the abutment.The device can then be lifted off the rail. A decond detent to detent recess engagement if provided would ensure the slide member is retained in a disengaged position.

The abutment may be continous or discontinous along the length of the rail which may be formed from any suitable metallic or non-metallic material. Preferablv the flange nearest the abutment and the abutment are discontinous along the rail which accomodates a plurality of electrical devices. The abutment and nearest flange are then formed or pressing out of the metallic rail. Alternatively, the abutment mav be continous along the rail and formed by an upwardly turned edge of a metallic rail. In this case a conventional DIN rail may be mounted to a sheet of metal having the upwardly turned edge forming the abutment.

An embodiment of the invention will now be described bv wav of example with reference to the acompanying drawings in which: Figure 1 is a perpsective view of an electrical mounting arrangement according to the invention and a device such as an MCB with a DIN rail, the device being ready for mounting on the DIN rail; Figure 2 shows an elevation of the arrangement of Figure 1 with the device seated on the DIN rail prior to full engagement with the rail; Figure 3 shows an elevation of the arrangement of Figure 1 with the device seated on the DIN rail in full engagement therewith; and Figure 4 shows a perspective view of the arrangment of Figure 1 with the device fully engaged with the DIN rail as shown in Figure 3.

In the drawings an electrical device such as an MCB but which may be any DIN rail secured device such as a residual current circuit breaker or time delay switch is shown at 1. The lower face 2 of the device 1 has a recess 3 and a lip 3 which extends from the lower face into the recess so as to engage under a flange 10 of DIN rail 12.

Also, above recess 3 is a protruding portion 6 of a slide member 7. The protruding portion is arranged to engage under a flange 14 which is punched out from the DIN rail 12. Also punched out from DIN rail 12 is an abutment 16. Flanges 10 and 14 of the DIn rail conform to the standard DIN measurements. Rail 12 is shown with only a single iocation for device 1, but normally the rail is extended in its transverse direction att right angles to a longitudinal direction in which flange 14 and abutment 10 tie.

Slide member 7 is retained in a slide way generally indicated at 18 within the device 1. Within the slide way is a sprung detent 20 which engages with one of two recesses 22 and 24 in the slide member. The sprung detent 20 may be provided with a sping or it may simply be a resiliently mounted protrusion. Recess 22 defines with the detent 20 a disengaged position of the slide member as shown in Figure 2. Whilst recess 24 defines with detent 20 an engaged position of slide member 7 as shown in Figure 3.

In order to clip the device 1 to the DIN rail 12 it is necessary to first check that the slide member 7 is in the disengaging position as shown in Figures 1 and 2.

The device 1 is then placed with its recess 3 over the flanges 10 and 14 to the DIN rail. The device 1 is then moved towards abutment 16 which then urges the slide member towards lip 4 until flange 10 comes up against an inner surface 26 as shown in Figure 3. At this point the detent 20 and recess 24 cooperate to urge the slide member into the final engaged position as shown in Figure 3. The protruding portion 6 to the slide member will then be under flange 14 so that the device is clipped onto the DIN rail by means of lip 4 and protruding portion 6.

In order to remove the device from the DIN rail the device is pushed away from abutment 16 so that flange 14 urges the slide member 7 outwardly until lip 4 is clear of flange 10. Device 1 can then be lifted off DIN rail.

In order to ensure the slide member is secured in the disengaged position the detent then springs into recess s as shown in Figure 2.

Slide member 7 can be provided with a slot 28 for accepting a tool to pull the slide member into the disengaged position whilst the device is removed from the consumer unit into which the DIN rail is mounted.

The detent and recess circuit arrangement can be varied so that one or more detents is or are provided on the slide member whilst recesses to engage with the detent are provided on the body of the device 1. The detent or detents and recess or recesses can be provided in any suitable position either on the side or top of the slide and slide way.

The DIN rail shown in the drawings can be formed of sheet steel or any other suitable strong material. In the case of a steel DIN rail the flange 10 is normally provided along the length of the rail in an uninterrupted form whilst flange 14 is merely punched out of the rail at intervals along the rail corresponding to each location of a said device 1. That is, a consumer unit will normally have a plurality of positions for devices.

Again the abutment 16 is consequently pressed out at each location corresponding to flange 14 but in an alternative arangement which can run the length of the rail. In the case of the abutment 16 running the length of the rail, this can be formed from a separate metal member, but can even be moulded from plastics as part of the consumer unit.

Claims (7)

1. An electrical device mounting arrangement comprising a rail having a pair of opposed outwardly turned flanges spaced apart in an longitudinal direction and an abutment spaced from the flanges in the same longitudinal direction, the rail being arranged to cooperate with a rail mounted electrical device having means to engage one said flange and a slide member to engage the other said flange, the abutment being arranged to co-operate with the slide member to urge it towards an engaged position on movement of the electrical device toward the abutment.

2. A mounting arrangement according to claim 1 wherein at least one detent and at least one detent receiving recess are provided to locate the slider member in the engaged position.

3. A mounting arrangement according to claim 2 wherein the detent or detents is or are arranged to assist movement of the slide member toward the engaged position.

4. A mounting arrangement according to any one of claims 1 to 3 so arranged and adapted that movement of the device away from the abutment causes the rail flange nearest the abutment to urge the slide member outwardly.

5. A mounting arrangement according to any one of claims 1 to 4 wherein a second detent and detent recess arrangement is provided to retain the slide member in a disengaged position.

6. A mounting arrangement according to any one of claims 1 to 5 wherein provision for mounting a plurality of said electrical devices side by side is provided by extending the outwardly turned flanges and abutment continuously or dis-continuously in a direction at right angles to said longitudinal direction.

7. An electrical device mounting arrangement substantially as described with reference to the accompanying drawings.