EP0617482A2 - Mains power supply plug - Google Patents

Abstract

In the case of a mains cable plug connection for electrical appliances and electrical tools, the plug which is connected to the electrical cable consists of two plug part halves which are connected to one another and on which latching vanes, which are flexible in an elastically resilient manner, are fastened from the outside by means of a common screw union, which latching vanes secure the plug in a positively locking manner by means of latching shoulders on both sides in the interior of a retaining socket into which it is inserted, with the aid of latching shoulders which engage behind corresponding locking recesses in the retaining socket. <IMAGE>

Description

State of the art

The invention relates to a power cord connector according to the preamble of claim 1.

In the case of electrical devices, it is both known to lead out of the device a clamped and correspondingly electrically contacting cable inside the device for producing the electrical connection to the mains socket, usually reinforced by a rubber grommet or something similar adjacent to the outlet point, or to provide the device with a connecting socket, into which the plug of a power cord can be inserted. For use in conjunction with power tools, especially hand-held power tools such as hand drills, screwdrivers, jigsaws and the like. the latter option is rare, because during the usually rough operation the mains cable plug can slip out of the socket on the device, either due to the constant vibrations or because the cable has been kept too tight.

On the other hand, there are often considerable problems with electrical handheld devices with a fixed power cord, because it is customary to wrap the power cord around the machine after use and to some extent stow it, because otherwise when the tool is stored, there will be other tools in particular the same place, the power cord can get tangled and a loose power cord disturbs and can also be damaged.

By wrapping around there arises the need to kink the power cord immediately upon exiting the device, which, with frequent use, leads to the power cord becoming brittle either in the area of the grommet or directly behind the grommet if reinforced by one will and problems can arise not only of the electrical contact with the device, but also safety problems if, for example, the phase connection line is exposed.

It is then very cumbersome to unscrew the whole machine in order to be able to properly re-arrange the cable connection on the device, for example by shortening the cable by the damaged section - such disassemblies are particularly expensive when the electrical device is a Half-shell system.

The invention is therefore based on the object of creating a mains cable connection for the electrical connection connections between any electrical device, in particular a power tool or electrical hand tool, which is securely and immovably positively on the device, in which it is inserted, is held, is simple and uncomplicated and can also be opened and repaired in the event of damage, so that it is not necessary to dispose of the entire power cable connection, as is essential for welded-in connecting parts.

Advantages of the invention

The invention solves this problem with the features of claim 1 and has the advantage that the plug is held securely and immovably in the receptacle, which is usually located on the device, due to positive locking, which are preferably present on both sides of the plug.

Nevertheless, an easy release of the plug from the device socket is possible by pressing the grip areas formed by latching wings together by manual pressing, whereby latching shoulders are released from locking recesses in the receptacle socket and the plug can be easily removed.

For this manipulation, one-hand operation is possible because the locking wings are opposite each other on the plug and can be gripped and pressed together on both sides by the thumb and forefinger, for example, which leads to the locking connection of the plug in the socket being released.

It is also advantageous that the plug can be completely disassembled, so that it can be easily replaced or repaired without the cable, as is otherwise necessary with welded connections, because inseparably connected to the plug connections, must be thrown away, or any commercially available plug is connected to the shortened cable, which requires some manual skill.

The invention therefore enables the reuse of the cable, which is complex and also costly because of the good insulation required, especially when it comes to power tools, if there should actually be a fault or damage in the connection area of the plug.

It is also advantageous that excellent contact is always guaranteed, since knife contacts are used which, when pushed on, cause the contacts to be cleaned due to the resilient pressing action.

Apart from the electrical contacts (knife contacts) to be connected separately with the cable connections, the entire plug consists of only five parts including the connecting grommet, which can be easily installed.

It is also of particular advantage that the latching wings on both sides are attached to the connector as the last assembly step and are spread apart by spring pressure from the connector, a common compression spring being used for both latching wings.

The structure of the plug is therefore of particular importance in such a power cord plug connection, while the receptacle, which is usually located on the device - is also conceivable to arrange the receptacle on the cable and the plug on the device, if desired - of a rather simple structure and also of parts of the housing wall of the power tool to be connected to the cable connection can be formed as a cavity.

This cavity then has inner contours that complement the outer shape of the plug so that it can be inserted into the socket without any problems, while at the same time electrical contact is made by penetration of contact tongues in the socket area into small metallic receptacles on the plug. These sockets in the plug can be of commercially available construction and form knife contacts by means of resiliently pressed metal tongues on both sides, between which the contact tongues of the device socket are inserted.

Advantageous further developments and improvements of the invention are possible through the measures listed in the subclaims. A supplementary embodiment is particularly advantageous, which consists in that, in order to simplify assembly, interlocking fitting parts in the form of projecting ribs or corresponding complementary grooves are provided on the two plug parts, which complement one another and ensure a perfect fit, initial centering thereby being possible, that a projecting pipe stub on one of the plug parts engages flush in a larger projecting pipe stub on the other plug part, which ensures the immediate, realistic orientation of the two plug parts with respect to one another without lengthy testing, and furthermore a continuous opening is formed in the plug by the two pipe stubs directed towards one another Includes a compression spring, which is then effective on both sides from the inside, which is then joined together with the basic connector parts by a simple Screw connection acts with the two locking sashes mounted between the compression spring.

drawing

Fig. 1

eine Draufsicht auf den Stecker, aus der auch der zugewandte federnde Rastflügel erkennbar ist;

Fig. 2

eine Seitenansicht des Steckers der Fig. 1 mit beidseitig angedeuteten Rastflügeln;

Fig. 3

eine der Darstellung der Fig. 1 vergleichbare Draufsicht mit weggenommenen oberen Steckerteil und an diesem außen anliegendem Rastflügel;

Fig. 4

einen Schnitt längs der Linie IV-IV der Fig. 3;

Fig. 5

einen Schnitt längs der Linie V-V der Fig. 3;

Fig. 6

einen Schnitt längs der Linie VI-VI der Fig. 3;

Fig. 7

einen Schnitt längs der Linie VII-VII der Fig. 3 und

Fig. 8

einen Schnitt längs der Linie VIII-VIII der Fig. 3; schließlich zeigen

Fig. 9

eine Ansicht des Steckers der Fig. 1 von vorn und

Fig. 10

lediglich eine der möglichen Ausführungsformen einer Aufnahmebuchse für den Stecker der Fig. 1 bis 9, vorzugsweise am jeweiligen Elektrogerät.

Exemplary embodiments of the invention are shown in the drawing and are explained in more detail in the following description. Show it:

Fig. 1

a plan view of the plug, from which the facing resilient locking wing can be seen;

Fig. 2

a side view of the connector of Figure 1 with locking wings indicated on both sides.

Fig. 3

one of the representation of Figure 1 comparable plan view with the upper connector part removed and this externally adjacent locking wing.

Fig. 4

a section along the line IV-IV of Fig. 3;

Fig. 5

a section along the line VV of Fig. 3;

Fig. 6

a section along the line VI-VI of Fig. 3;

Fig. 7

a section along the line VII-VII of Fig. 3 and

Fig. 8

a section along the line VIII-VIII of Fig. 3; finally show

Fig. 9

a view of the plug of FIG. 1 from the front and

Fig. 10

only one of the possible embodiments of a receptacle for the plug of FIGS. 1 to 9, preferably on the respective electrical device.

Description of the embodiments

The basic idea of the present invention is a removable, that is to say screw-on and, in this respect, environmentally friendly plug with external resilient latching possibilities To create especially for an electric hand tool that engages with cams in the housing of the power tool, receives a secure, form-fitting seat due to the engagement and can be released again just as easily by resiliently pressing two opposite locking wings on the connector with one hand, thereby projecting locking shoulders Locking recesses in the socket area are released and the plug can be pulled out.

The structure and basic shape of the plug 10 can best be seen from the illustration in FIG. 4; the plug comprises two main plug parts, namely a first half 11 and a cover plug part 12, which is referred to below as the basic plug part, the base plug part 11 being looked at in FIG. 3 with the cover plug part 12 removed.

As best shown in FIGS. 1, 2 and 4, latching wings 13a, 13b are attached to the outside of the joined two connector part halves, with recesses 14a, 14b being formed in the front area of each connector part half (see also FIG. 5 in Connection with Fig. 4), in which front, inward, that is, towards each other towards the assembled state approaches 15a, 15b of each locking wing are inserted and held by mutual, mutually projecting ribs and recesses. Such ribs engaging in recesses on each latching wing extension 15 are designated by 16 in FIG. 5.

The construction of the plug is completed by a grommet 17 or extension attached in the rear part of the plug, which is anchored by an annular recess 17a takes place in its front area in the plug, into which protruding semicircular shoulders 18a, 18b penetrate, complementing a full circle and holding the grommet.

Apart from the electrical leads, which can be clearly seen in FIG. 3, with the small metallic receptacles 19a, 19b arranged at their ends, which, forming knife contacts in their rear area with the two electrical leads 20a, 20b provided here, are preferred by crimping or pressing are connected, then the connector comprises a total of five parts, namely the two connector part halves 13a, 13b, the rear grommet 17 and the two laterally attached locking wings 13a and 13b.

The two connector part halves are connected by providing axially extending projections 21 in the edge region on one of the halves, preferably on the basic connector part 11 which can be seen in FIG. 3 and which (compare also FIGS. 5 and 6) into corresponding longitudinal grooves 22 Engage the cover plug part 12. It goes without saying that any interlocking connection options can be provided here.

A particularly advantageous variant consists in the fact that for initial orientation and at the same time for the formation of a bore 23 (FIG. 4) leading through both plug part halves, which serves to receive a compression spring 24, a central raised, tubular one on one of the plug part halves, preferably on the basic plug part 11 Ring projection 25 is formed, in which a ring projection 26 of smaller diameter engages the other connector part half, that is to say from the cover part 12, so that these two parts intermesh telescopically and at the same time form a passage and receiving bore for the compression spring 24 which is open on both sides to the outside, which then acts on both sides, as best shown in FIG. 4, on the latching wings 13a, 13b attached to the connector part halves and following them tries to spread outside due to their spring force. For this purpose, the spring ends are received in cup-like receiving recesses 27 on the inside of the locking wings 13a, 13b.

The installation of such a plug is then carried out in such a way that the two receptacle sockets are first connected to the two electrical leads 20a, 20b of the cable 20 guided through the grommet 17 by soldering, crimping or another type of connection, the socket 19b being particularly good in FIG. 8 can be seen and consists of two resiliently pressed metallic contact surfaces 28 which are integrally connected to one another in the rear part. These contact surfaces 28 are bent forward, so that even in the case of slight misorientation, the contact tongues 21, only schematically indicated in FIG. 10, of a receptacle 30 for the plug shown there can easily penetrate and the constant spring force of the contact surfaces results in excellent contacting in the manner of knife contacts results.

Subsequently, the metallic receptacles 19a, 19b are inserted into the basic connector part 11, as shown in FIG. 3, whereby orientation and holding functions result in the receiving area, for example by receiving a lateral projection 29 from a correspondingly shaped lateral receiving opening 30 of the basic connector part housing and through the tube shape at the same time 25 of the central passage opening gives an opposite stop at 31 for the respective receiving bushing 19a, 19b. This achieves a pre-fixation of the metallic receptacle or contact sockets 19a, 19b in the basic connector part 11, which are finally fixed after connecting the two connector part halves by mutually facing transverse ribs 31 on one or both connector part halves, which secure the inserted contact sockets. Inward projections are also provided in the area of the cable end 32 still emerging from the connector, so that it is clamped in the connector when the two connector halves are screwed together as best shown in FIG. 7, from which the two clamping projections 33 are also clearly visible, which serve to clamp and compress the cable end 32 and form a compressed oval shape 34 for the passage of the cable end 32.

The two halves of the connector part are therefore connected with two screws 35, as shown in FIG. 7, which are formed by mutually aligned openings 36 in the rear part of the two halves of the connector part and which also partially telescope into one another, as is also shown in FIG. 7 for complete orientation and bracket of the two connector halves.

Only after the assembly has progressed so far with simultaneous clamping of the grommet 17 with its annular projection 36, are the two locking wings with their front lugs on both sides attached to the connector part halves 11, 12 screwed together after the compression spring 24 is still inserted into the bore 23 has been.

Also in the connector part halves, as shown in FIG. 4, a tubular projection 37 on the locking wing 13a penetrates to the passage end of the preferably oval or approximately rectangular passage opening 38 in both connector part halves (compare FIG. 3), so that it is simple, then from the other side to insert a screw 39 and to connect the two locking wings 13a, 13b by anchoring their front projections or shoulders 15a, 15b to each other and simultaneously to the assigned connector part halves. The compression spring 24 spreads the latching wings 13a, 13b apart, so that the latching projections 40 formed on both sides thereof are further apart than corresponding recesses 41 which are formed by the corresponding receiving inner wall on the respective device socket and which are only representative in FIG. 10 are indicated for all possible embodiments. If, therefore, a fully assembled plug, as shown in FIGS. 1 and 2, is inserted into the receptacle 30 of FIG. 10, the locking wings 13a, 13b, which are spread apart laterally by the pressure of the spring 24, are pressed together until the locking lugs or locking shoulders 40 fall into corresponding locking recesses 41 of the receiving bush 30 caused by the spreading pressure of the compression spring 24 and engage behind them. In this way, the plug 10 is firmly seated in the receptacle 30 and is no longer detachable even with the roughest treatment, and not even if an inwardly directed pressure is accidentally exerted on one of the locking wings. Only when the operator's hand is exerted on the two gripping surfaces 42 of the latching wings, for example by the thumb and index finger, in each case toward the inside, that is to say toward one another, can the latching wings be moved by the slight distance that the latching lugs have or need locking shoulders 40 to get free from the recesses 41 of the receptacle 30, then compress, whereupon the plug can be easily pulled out of the plug socket while simultaneously loosening the electrical contact connections. The contact tongues 29 of the socket then slide out of the interior of the electrical contact sockets with spring pressure constantly exerted by the contact surfaces 28 until they are also released.

It goes without saying that the connector halves 11 and 12 connected to one another each form half recesses to the front, which complement each other to form a rectangular overall passage recess 43 through which the contact tongues 29 pass in order to be received by the metallic receptacles 19a, 19b located behind them ( Fig. 9).

In conclusion, it is pointed out that the claims and in particular the main claim attempts to formulate the invention without extensive knowledge of the prior art and therefore without restrictive prejudice. It is therefore reserved to consider all the features shown in the description, the claims and the drawing both individually and in any combination with one another as essential to the invention and to lay them down in the claims.

Claims (9)

Mains cable plug connection for electrical devices and tools, in particular for electrical hand tools, with plug with cable and associated receptacle with configuration complementary to the plug, characterized by outer, mutually opposing, resilient latching wings (13a, 13b) on the plug (10), which spring outwards spread out, inserted into the receptacle with catch shoulders (40), engage behind corresponding locking recesses (41) in the interior of the associated receptacle (30). Mains cable plug connection according to claim 1, characterized in that the latching wings (13a, 13b) are attached to the outside of the plug (10) and are screwed together in that a common screw is passed through a plug hole in its front part and through both latching wings. Mains cable plug connection according to claim 2, characterized in that the plug consists of two, approximately identical halves of the plug part (11, 12), which are connected to one another by receiving the electrical contact connections and which have front, open-front receiving pockets for attachments (15) Form two latching wings (13a, 13b), the connecting screw (39) of the latching wings (13a, 13b) being guided between the openings (43) for the electrical receptacle contact sockets (19a, 19b). Mains cable plug connection according to one of claims 1 to 3, characterized in that the latching wings (13a, 13b) are biased to the outside by a common compression spring (24) which is guided through a through bore (23) of the two connector part halves (11, 12) and is stored in this. Mains cable plug connection according to one of Claims 1 to 4, characterized in that the latching wings (13a, 13b) form grip surfaces (42) opposite one another on the plug (10), in the region of which the latching shoulders (40) are arranged on both sides of each grip surface. Mains cable plug connection according to one of claims 1 to 5, characterized in that to facilitate assembly on one of the lugs (15a) of one locking lug (13a) running at right angles to the main part of each locking lug, a non-circular material extension into the area of the opposite lug (15b) of the Another locking wing (13b) is guided, which is received in a non-circular through hole (38) formed by two interconnected connector halves. Mains cable plug connection according to one of Claims 1 to 6, characterized in that the connector part halves (11, 12) are fixed to one another by respective rib-like projections (21) and correspondingly assigned recesses (22) in the other part, one of the connector part halves (basic connector part 11) a tubular projection extends approximately in the middle, into which a further tubular projection engages on the other plug part (cover part 12) to form the passage and bearing bore (23) for the common biasing spring (24) of the two latching wings which passes through both plug parts. Mains cable plug connection according to one of Claims 1 to 7, characterized in that the two basic plug part halves (11, 12) are screwed together by through-bores arranged on both sides of the received electrical cable end (32) for simultaneous clamping of the cable end, a cable grommet (17) in one of the two Half of the connector part is formed in each case, and the assembly of the connector is completed by the middle screw (39), which simultaneously fixes the two latching wings (13a, 13b) in the front area. Mains cable plug connection according to one of Claims 1 to 8, characterized in that metallic receptacle contact sockets (19a, 19b) which form knife contacts are inserted in receptacle spaces formed by housing projections in one of the plug part halves (basic plug part 11), the corresponding receptacle (30) projecting tongues on the respective electrical device (29) which are received by resiliently pressed contact partial surfaces (28) of each receptacle with simultaneous resilient spreading.

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