Title of Invention

"A LEAD SEALABLE LOCKING DEVICE AND AN ELECTRIC DEVICE"

Abstract

There is disclosed a lead-sealable locking mechanism for making an actuating means, e.g. an electric terminal of an electric" appliance, inaccessible and for lead-sealing the same, said mechanism being easy to assemble and adapted to be manufactured cheaply. This lead-sealable locking mechanism (20) comprises a plug-in section (2) which can be pushed into a push-in orifice (4) of an electric appliance (1). The push-in orifice (4) extends transversely to an access orifice (19) through which one has e.g. access to an electric terminal (5) having as actuating means a locking screw which is, for example, loosened or tightened by means of a screwdriver. By the lead-sealable locking mechanism (20) being adapted to be pushed into and out of the push-in orifice, the access orifice (19) to the electric terminal can be blocked or unblocked. The plug-in section has a plug-through orifice (3) for plugging through a seal wire (6), so that the lead-sealable locking mechanism is lead-sealable with the electric appliance in the position covering the terminal.

Full Text

Lead-Sealable Locking Device Specification The present invention relates to a lead-sealable locking device for making an actuating device for an electrical device such as a terminal, inaccessible and lead-sealing it, to an electrical device such as a power safety switch or the like and to a system consisting of the lead-sealable locking device and the electrical device. In electrical devices such as for example a power safety switch there are normally provided terminals in which an electric conductor Is firmly clamped. Such a clamping point usually consists of a contact plate and a screw, said contact plate comprising in the middle a bore through which a screw is inserted and screwed in a subjacent housing section so that the electric conductor being inserted between the screw head and the electric contact plate is firmly clamped between the screw head and the contact plate, when the screw is screwed in. In devices in which it is either prescribed or at least desired that it is not possible for unauthorized persons to easily release the terminals in an unnoticed manner, lead-sealing was performed hitherto. Thereby it could be checked immediately whether the terminal was manipulated, since in such a case the lead seal had to be broken. For example in a power safety switch there was provided a flap which was flexibly mounted onto the power safety switch so that an access for releasing or fixing the electric terminal in the electrical device was only possible in the opened state, while the access was locked in the closed state. After an electric conductor had been firmly clamped to the clamping point, the flap was closed and lead-sealed with a conventional lead-sealing wire. This solution, on the one hand, presupposes a costly flap construction which made the manufacture of such a power safety switch more expensive. Furthermore the handling of such a flap was uncomfortable. Therefore it is the object of the present invention to develop a lead-sealing device in electrical devices such as power safety switches and the like, wherein said device is easy to assemble and can be produced at low cost. This object is achieved by the features of claims 1, 8 and 15. By the provision of a lead-sealable locking device which can be pushed into a plug-in opening in the electrical device, wherein said device is provided in addition with a through opening into which a lead-sealing wire can be inserted it is possible to make a device inaccessible and lead-seal it at low cost. The movability of the lead-sealable locking device in an opened and a closed position in which the access for releasing or fixing for example an electric terminal is alternatively covered or released allows an easy access to the clamping point and likewise a comfortable covering and sealing possibility of this clamping point, since by pushing the lead-sealable locking device and withdrawing it an access opening of the .electrical device, through which an auxiliary tool such as a screw driver or the like can be inserted, is released or blocked to arrive at the clamping point so as to release or fix a clamping screw. Furthermore the lead-sealing is simplified by providing a through opening in the lead-sealable locking device into which the lead-sealing wire has to be simply inserted. The insertion of the lead-sealing wire is still further simplified by providing a groove.like channel on the upper side of the insert section, whereby the channel ends in the through opening so that the lead-sealing wire is simply inserted into the groove and guided therein and subsequently glides automatically through the through opening. The insertion of the lead-sealing wire can be still further simplified by chamfering the groove-like channel at its entry so that a lead-sealing wire is inserted more safely into the groove-like channel. In order to fix the lead-sealable locking device in the inserted state (i.e. in the closed state in which the access to the clamping point of the electric terminal is covered) a latch is formed at the end of the insert section, wherein said latch can snap into a corresponding snap section in the electrical device. It is advantageous that this latch is has a projection which is can flexibly snap into a correspondingly formed snap section of the electrical device, whereby said section preferably comprises an undercut. In order to give the insert section of the lead-sealable locking device the necessary flexibility in the end, a slit is provided in the end area approximately in the middle so that the latch can be compressed a little when being inserted into the plug-in opening, if the dimension of the plug-in opening is somewhat smaller than the insert section. When the latch engages into the undercut section, the prestressed insert section is released and the latch really snaps into the undercut and is thus fixed. In this position it is easy to insert the lead-seali-ng wire, since no attention has to be paid that the lead-sealable locking device does not drop out of the plug-in opening, when the lead-sealing wire is inserted into the through opening. A further advantageous embodiment of the subject matter of the invention is that the lead-sealable locking device is provided with at least one clamping bar which protrudes perpendicularly with respect to the insert direction. This clamping bar serves to snap into a groove, when the lead-sealable locking device is withdrawn, said groove being provided transversely with respect to the insert direction and provided at the plug-in section in the electrical device. Hence the following advantages are achieved: By the locked position of the lead-sealable locking device the lead-sealable locking device cannot drop out of the plug-in opening, since the clamping bar snaps into the groove, when the lead-sealable locking device is withdrawn. Moreover authorized personnel who has broken the lead-sealable locking device can release the clamping screw of the terminal without completely removing the lead-sealable locking device. Rather the lead-sealable locking device only has to be brought into the withdrawn position. Subsequently the cap can simply be inserted again so that the access to the clamping screw is covered again by the insert section of the lead-sealable locking device. Of course, an electrical device has to have a corresponding plug-in opening which has formed a groove transversely with respect to the insert direction into which groove the clamping bar can engage. Further advantageous embodiments and variations of the present invention are the subject matter of the subclaims. The present invention shall be explained now in greater detail on the basis of a detailed description of the present embodiments with reference to the enclosed drawings. On this occasion it shall be stressed once again that the present invention is not restricted to a power safety switch, but is rather suited for any electric terminal. Figure 1 is a perspective illustration of a power safety switch with a lead-sealable locking device and a lead seal according to the embodiment of the present invention. Figure 2 is a perspective view of an electrical device with a lead-sealable locking device without a lead seal. Figure 3 is a perspective individual illustration of the lead-sealable locking device. Figure 4 is a perspective illustration of an electrical device with a lead-sealable locking device, but without a cover. Figure 5 is a perspective illustration of the electrical device with the lead-sealable locking device in a withdrawn position, wherein the cover is illustrated as half cut for a better understanding . Figure 6 is a perspective enlarged illustration from figure 5. Figure 7 is a perspective illustration of a further embodiment of a lead-sealable locking device according to the present invention. Figure 1 shows an overall illustration of a lead-sealed electrical device. A lead-sealable locking device 20 is pushed into a plug-in opening 4 of the electrical device 1. A lead-sealing wire 6 is inserted through a through opening 3 through the lead-sealable locking device 20 and embraces a cover 16 of the electrical device 1. Both end areas of the lead-sealing wire 6 are leaded with each other so that the lead-sealable locking device 20 cannot be withdrawn any more from the plug-in opening 4 without breaking the lead-sealing wire or the lead seal. Figure 2 shows the same illustration as figure 1, but here the lead-sealing wire and the lead seal have not been shown. With reference to figure 3 the lead-sealable locking device shall be explained in greater detail now. The lead-sealable locking device substantially consists of an insert section 2 and a contact section 8 which both extend substantially at right angles with respect to each other. The insert section 2 has a pair of latches 9 at the end and a slit 12 which makes the two latches flexible. Furthermore at the end of the insert section 2 there is provided a clamping bar 11 which extends from the insert section perpendicularly upwards in figure 3. As can be seen in figure 3, the clamping bar 11 is rounded or chamfered in order to make a movement of the lead-sealable locking device easier. The clamping bar 11 namely serves to secure the lead-sealable locking device against dropping out, if the lead-sealable locking device is moved in an open position, as it is illustrated in figure 5. As can be further seen in figure 5, a groove 17 is provided in the cover 16 of the electrical device 1 into which groove the clamping bar 11 snaps so that the lead-sealable locking device cannot easily drop out or can only be withdrawn by the exertion of effort. In order to make the withdrawal and the first assembling and insertion easier, the chamfers or roundings of the clamping bar 11 are provided. The slit 12 in the insert section 2 (see figure 3) serves to make the latches 9 flexible so that the latches can be compressed a little inwards. This is helpful, when the lead-sealable locking device is assembled, i.e. when it is pushed into the closed position, since the latches 9 in undercuts 10 snap into the electrical device 1. In order to avoid a loose positioning of the lead-sealable locking device 20 with too much play, an area in front of the undercut 10 is provided at the end of the plug-in opening 4, wehrein the size of said area is determined such that the first contact point with the latch 9 of the lead-sealable locking device 20 is slightly overlapping. This means, that the latches are pressed a little inwards in the direction of the slit 12, when the insert section 2 is further inserted. As soon as the latches reach the undercut, they snap into the undercut due to their prestress and thus the lead-sealable locking device is fixed against withdrawal. Figure 6 shows in enlarged illustration the lead-sealable locking device in the withdrawn state so that the undercut 10 in the plug-in opening 4 of the electrical device 1 can be seen well. Figure 4 shows a state in which the lead-sealable locking device is completely inserted, i.e. in which the latches 9 have engaged into the undercuts 10 and the lead-sealable locking device is secured against withdrawal. Figure 5 shows a state in which the lead-sealable locking device is withdrawn, wherein the cover 16 of the electrical device is only half illustrated so as to give the observer a view of the plug-in opening 4. From figure 5 it can be seen that in the state shown there the access to the clamping point 5 is freely accessible from above. Figure 7 shows a further embodiment of the present invention in which plural lead-sealable locking devices disposed side by side are formed integrally, wherein between the individual lead-sealable locking devices only thin predetermined breaking points connect the individual lead-sealable locking devices so that these devices can be easily separated. This has the advantage that tho lead-sealable locking devices can be given to the service personnel for example in larger quantities; the personnel then separates and installs individually, according to requirement, individual lead-sealable locking devices from the series. Of course, the number of the integrally formed lead-sealable locking devices is not restricted to four, but can be manufactured in any number. Claims 1. A lead-sealable locking device (20) for locking an actuating device of an electrical device (1), said locking device com prising an oblong insert section (2) insertable into a corre sponding plug-in opening (4) of said electrical device for locking an access to said actuating device and a tip-stretched handle having a through opening (3) for inserting a lead- sealing wire (6) so that said locking device can be sealed in a position in which it locks said actuating device. 2. A lead-sealable locking device according to claim 1, charac terized in that said insert section (2) for inserting the lead- sealing wire (6) comprises on the one side a groove-like chan nel (7) which ends in said through opening (3). 3. A lead-sealable locking device according to claim 1 or 2, characterized in that said insert section (2) comprises at least one latch by which said lead-sealable locking device can be firmly clamped in the inserted state in a corresponding snap section (13) of said electrical device. 4. A lead-sealable locking device according to the preceding claim, characterized in that said latch (9) is formed trans versely with respect to the insert direction and can snap flexibly into the snap section (13) having a correspondingly formed undercut (10). 5. A lead-sealable locking device according to any one of the preceding claims, characterized in that said lead-sealable locking device has at least one clamping bar (11) which is pro vided at said insert section (2) and protrudes perpendicularly with respect to the insert direction. 6. A lead-sealable locking device according to any one of thepreceding claims, characterized in that said insert section (2) comprises a slit (12) at the end in the middle. 7. A lead-sealable locking device according to any one of the preceding claims, characterized in that said groove-like chan nel (7) is chamfered or bent at its entry. 8. An electrical device such as a power safety switch or the like comprising an access opening (19) to an actuating device and a plug-in opening (4) passing through to the access opening (1) and extending substantially in a transverse position thereto for inserting a lead-sealable locking device according to any one of claims 1 to 7. 9. An electrical device according to the preceding claim, char acterized in that said plug-in opening (4) comprises a snap section (13) into which a latch (9) of said lead-sealable lock ing device can snap, when said locking device is completely in serted. 10. An electrical device according to the preceding claim, char acterized in that said snap section (13) comprises an undercut (10) . 11. An electrical device according to any one of the preceding claims 8 to 10, characterized in that said electrical device comprises a main housing portion (15) and a cover (16). 12. An electrical device according to the preceding claim, char acterized in that said plug-in opening (4) is formed between the cover (16) and the main housing portion (15). 13. An electrical device according to any one of the preceding claims 8 to 12, characterized in that a groove (17) extending transversely with respect to the insert direction is provided in said plug-in opening (4). 14. An electrical device according to any one of the preceding claims 8 to 13, characterized in that said actuating device is a clamping screw for an electric clamping point (5) to manually release or firmly clamp an electric conductor. 15. A system consisting of a lead-sealable locking device (20) according to any one of the preceding claims 1 to 7 and an electrical device (1) such as a power safety switch or the like according to any one of the preceding claims 8 to 14. 16. A lead-scalable locking device for locking an actuating device of an electrical device substantially as herein described with reference to and as illustrated by the accompanying drawings. 17. An electrical device substantially as herein described with reference to and as illustrated by the accompanying drawings. 8. A system consisting of a lead-scalable locking device substantially as herein described with reference to and as illustrated by the accompanying drawings.

Documents:

in-pct-2000-043-del-abstract.pdf

in-pct-2000-043-del-claims.pdf

in-pct-2000-043-del-correspondence-others.pdf

in-pct-2000-043-del-correspondence-po.pdf

in-pct-2000-043-del-description (complete).pdf

in-pct-2000-043-del-drawings.pdf

in-pct-2000-043-del-form-1.pdf

in-pct-2000-043-del-form-19.pdf

in-pct-2000-043-del-form-2.pdf

in-pct-2000-043-del-form-3.pdf

in-pct-2000-043-del-form-5.pdf

in-pct-2000-043-del-gpa.pdf

in-pct-2000-043-del-pct-210.pdf

in-pct-2000-043-del-petition-137.pdf

in-pct-2000-043-del-petition-others.pdf