CZ257897A3 - Receptacle for electrical measuring instrument - Google Patents

Abstract

An electrical connecting plug of a type that connects with an item of equipment has a moulded body of insulating material [1]. The end section has a pair of rectangular entry points [6] and internally there are contacts for live and neutral. A circular hole [7] is provided for an earth connection. The plug fits into a shaped aperture in the equipment housing and this has inset connector pins.

Description

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a socket for an electrical appliance having at least two receptacles for flat pins, the socket being non-circular and symmetrical with respect to the axis of symmetry extending transversely to the larger transverse dimension of the socket. The invention also relates to a plug for an electrical apparatus with a fork receptacle and receptacles adapted thereto, the fork receptacle and the receptacle being non-circular in cross-section perpendicular to the insertion direction and symmetrical to the axis of symmetry extending transversely to the largest dimension of this cross-section.

BACKGROUND OF THE INVENTION

Such sockets for electrical apparatus are widely known. The socket, together with the plug plugged into this socket, forms a socket-plug combination for the electrical apparatus that allows the electrical apparatus to be disconnected from the power cord. The socket is located on the power supply cord and the plug is rigidly arranged in the electrical apparatus so that the plug pins cannot be energized when not connected. A distinction is made between sockets and plugs with and without protective conductor. Known sockets and plugs without a protective conductor have a cross-section consisting essentially of two adjacent sections of circular arcs. In the cross-section delimited by these sections of circular arcs, pin receptacles are provided. These sockets and plugs are used to connect devices with protective insulation, such as portable radios or the like. Sockets and plugs with protective conductor are used for connecting eg computers, monitors or hi-fi devices. A distinction should be made between sockets and plugs for electrical appliances that become hot or hot during operation. Sockets and plugs for warming up electrical devices must withstand higher temperatures. For these socket-plug systems, sockets with a substantially rectangular cross-section with two substantially bevelled corners are preferably used on the power supply side. With respect to the dividing axis, which runs parallel to a larger cross-sectional dimension, the markedly bevelled corners are arranged at the top, i.e. above the dividing axis. The cross-sectional area below the dividing axis has only slightly rounded corners. This implies that the cross-section is asymmetrical with respect to said dividing axis, giving the user visual instructions for inserting the drawer in the correct position. In the area of the cross-sectional area with bevelled corners, a flat pin receptacle is arranged approximately in the middle, into which the protective contact pin of the plug is inserted when the socket is connected to the plug. In the remaining cross-sectional area of the drawer there are two berths for flat pins, in which there is voltage when connected to the mains. The two pins for the power supply and the pin contact are arranged at the top of the triangle.

In view of the prior art described, the object of the invention is to find a socket structure for an electrical apparatus which is characterized by a geometrically simple, stable and ergonomically advantageous solution.

SUMMARY OF THE INVENTION

This object is solved and the drawbacks of the known electrical appliance sockets are largely eliminated by an electrical appliance socket having at least two flat-pin receptacles, the socket having a cross-section perpendicular to the insertion direction non-circular and symmetrical to the symmetry axis extending transversely to this The invention is characterized in that a dividing axis extends transversely to the axis of symmetry and the cross-section of the drawer above and below the dividing axis is defined by convex arcs, both convex arcs having essentially the shape of segments of circular arcs and having different radii from each other. The cross-section thus has an ellipse-like shape, the transition regions between said convex arcs being also rounded. An embodiment in which the radius of the convex arc located above the dividing axis is greater than the radius of the convex arc located below the dividing axis is preferred. For example, the radius of the upper convex arc may be in the range of 45 to 55 mm, preferably 50 mm, while the radius of the lower convex arc is in the range of 35 to 40 mm, preferably 37 mm. It is essential that the center of the convex arc with a larger radius is outside the total cross-sectional area of the drawer, while the center of the convex arc of smaller radius is located within the area of this overall cross-section, both centers being on the axis of symmetry of the drawer. In addition, it is possible for the two convex arcs extending above and below the dividing axis to be composed of segments of circular arcs with different radii. This results in an ergonomically advantageous drawer design. The drawer in this embodiment is particularly well gripped by hand. The visual instructions for positioning the drawer correctly on the respective plug for the user already mentioned in the prior art result from the asymmetrical non-circular design of the cross-section of the plug and the respective plug.

A further advantageous embodiment of the drawer according to the invention consists in that the cross-sectional dimension of the drawer between the transition regions connecting the different convex arcs to each other is markedly larger than the perpendicular largest dimension of this cross-section. This solution results in a relatively flat design of the drawer. Together with the cross-sectional areas above and below the dividing axis, which are delimited by convex arcs in the form of portions of circular arcs, this results in an ergonomically advantageous drawer shape. Preferred is a dimension ratio in the range of 15: 10 to 20; 10, in particular 17: 10. In a preferred embodiment, the larger cross-sectional dimension is approximately 34 mm and the smaller dimension perpendicularly measured thereto is approximately 20 mm. It is further preferred that the depth of insertion of the socket into the plug receptacle in the electrical apparatus approximately corresponds to the largest dimension of the cross-section of the socket. That is, the ratio of the largest dimension of the receptacle cross-section to the insertion depth of the receptacle is about 1: 1, which, taking into account the above dimensions, means that the insertion depth of the receptacle into the receptacle is approximately 34 mm.

It is further advantageous if the flat pin receptacles are arranged asymmetrically with respect to the dividing axis between the transition regions and are displaced towards the cross-sectional area defined by the more curved convex arc. As already indicated, the socket is asymmetrical with respect to the dividing axis, i.e. the connection between the transition regions. At the same time, the socket is symmetrical with respect to the axis of symmetry, which runs perpendicularly to said dividing axis. Accordingly, in the case of a symmetrical arrangement of the flat pin receptacles with respect to the axis of symmetry, which extends perpendicularly to the junction of the transition regions, these flat pin receptacles are simultaneously arranged asymmetrically with respect to said dividing axis. In a preferred drawer design in which the convex arcs defining the cross-sectional areas of the drawer above and below this connector, i.e., the dividing axis, have different radii from each other, the flat pin receptacles are displaced towards a more curved convex arc, i.e. the radius of the convex arc that delimits this region. Advantageously, the flat pin receptacles are displaced parallel to the connection between the transition regions, i.e., the dividing axis, so that the connection between the centers of the flat pin receptacles passes at least approximately the center of gravity of the entire cross-sectional area of the drawer. The convex arcs with different radii do not coincide with the intersection of the junction of the two transition regions with an axis of symmetry that runs perpendicular to this junction. The dowel beds are otherwise similar to those known in the art, i.e. they have rectangular orifices in cross-section. In the receiving opening, which extends in the longitudinal direction of the drawer, there is a metal clamping sleeve which represents the electrical contact.

A further improvement of the drawer according to the invention is that the drawer is provided with a snap-in thumb protruding from its periphery, which is springed perpendicular to the longitudinal direction of the flat-pin receptacles. As a result, the plug-plug assembly is secured against unintentional disconnection. When the plug is inserted into an appropriately designed fork receptacle in the electrical apparatus, the snap-in thumb engages in a corresponding recess. This engagement can only be unlocked consciously, by means of a corresponding pushbutton or the like arranged in the region of the fork seat. The snap-on thumb, which is arranged on the socket, can be pushed against the action of the compression spring by means of a button on the electrical apparatus, so that the socket can then be pulled out of the fork receptacle in the electrical apparatus. The described pull-out securing device is particularly advantageous when using the plug according to the invention in conjunction with movable electric devices such as vacuum cleaners, electric lawn mowers and the like. In these cases, otherwise, due to tensile stresses on the power cord and plug, the plug may be unintentionally pulled out of the plug receptacle in the electrical apparatus. This is avoided by the snap-in thumb according to the invention.

It is further preferred that the snap-in thumb is arranged on the less curved outer side of the drawer.

It is particularly advantageous if the snap-in thumb is arranged approximately in the middle between the flat pin receptacles. In a preferred embodiment, in which the upper cross-sectional area of the drawer is delimited by a less curved convex arc, the snap-in thumb arrangement provides the advantage that the snap finger is in an ergonomically favorable position when gripping the drawer by hand , which then allows the socket to be plugged into a plug receptacle in the electrical apparatus. It is also possible for the fork receptacle in the electrical apparatus to be provided with a leading chamfer for the snap-in thumb, which causes the snap-in thumb to be compressed when the plug is inserted.

As mentioned above, the socket may be provided with a protective contact. This can be done in such a way that, in the cross-section of the drawer, a round pin housing is arranged between the flat pin receptacles. In the height direction, the bed is shifted towards a more curved convex arc, i.e. into the lower region of the drawer cross-section. However, an embodiment in which the round pin housing is arranged in the cross-section of the drawer is arranged between the flat pin housing. In the design of the protective conductor socket, the round pin receptacle is provided with a corresponding round contact clamp. In the design of the socket without protective contact, the socket for the round plug is electrically non-conductive, i.e., blind.

The invention further relates to a plug for an electrical apparatus with a fork receptacle and a receptacle adapted thereto, wherein the fork receptacle and the receptacle are non-circular in cross-section perpendicular to the insertion direction and symmetrical to the symmetry axis extending transversely to the largest dimension of this cross-section. The principle of the invention consists in that a dividing axis extends perpendicular to the axis of symmetry and the cross-sectional areas above and below this dividing axis are defined by convex arcs, the two convex arcs essentially having the shape of segments of circular arcs with different radii. The described solution achieves a geometrically simple construction with an excellent drawer insertion process, since the fork bed guides the drawer when it is inserted into the fork bed. When the drawer is slightly rotated, the convex arcs ensure that the drawer is rotated relative to the forks. The drawer is automatically brought into the necessary insertion position.

It also follows from the described geometrical conditions that, despite only a slight asymmetry, effective blocking is provided in the event of erroneous handling. For example, it is not possible to insert the drawer into the forks in a 180 ° -positioned position. In this case, said automatic fork bed guidance also does not apply. The user cannot then connect the plug to the plug in the electrical appliance or force it, thus eliminating the malfunction of the system.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS The invention is further elucidated with reference to the accompanying drawings, in which: FIG.

FIG. 1 is a general perspective view of a first embodiment of a socket for an electrical apparatus according to the invention, with a power cord and a conventional electrical plug;

FIG. 2 is a perspective cross-sectional view of a fork of an electric apparatus, with a fork seat, also relating to the first embodiment;

FIG. 3 is a side cross-sectional view of the receptacle of FIG. 1 and the plug of the electrical apparatus of FIG. 2;

Fig. 4 is a view corresponding to Fig. 3, but with the plug plugged into the plug receptacle in the plug of the electrical apparatus;

FIG. 5 is a perspective view of a second embodiment of the drawer;

FIG. 6 is a front view of the drawer of FIG. 5;

7 shows a side view of the drawer; FIG.

FIG. 8 is a plan view of the drawer;

FIG. 9 is a cross-sectional view of the drawer in the plane IX - IX of FIG for flat pin; FIG. 10 is a section along the line X - X of FIG. 9; FIG. 11 is a front view of a second embodiment of an electric plug apparatus, which is arranged in an electric apparatus i; FIG. 12 is a section along the line XII-XII in FIG. 11; FIG. 13 is a view corresponding to FIG the second embodiment of the socket and plug is electric 5 to 12; FIG. 14 is a view corresponding to FIG a third embodiment; FIG. 15 is a section along the line XV - XV in FIG. 14; FIG. 16 is a view corresponding to FIG in the second embodiment of FIGS. 5 to 10 is plugged in a plug of an electrical apparatus in a third embodiment 14 to 15; FIG. 17 is a side view of a third embodiment of the drawer; FIG. 18 is a view corresponding to FIG the embodiment of FIG. 17; and

FIG. 19 is a plan view of a third embodiment of the drawer.

DETAILED DESCRIPTION OF THE INVENTION

1 shows a socket 1 for an electrical appliance 10 with a power cord 2 connected to the socket 1 and a conventional power plug 3 connected to the other end of the power cord 2. FIGS. 1 to 4 show a first embodiment of the power cord. sockets 1.

The socket 1 is non-circular in a cross-section perpendicular to the insertion direction r, with an x-axis of symmetry extending transversely to the largest dimension b of this cross-section. As can be seen from FIG. 1, the drawer 1 consists essentially of two parts arranged one behind the other. Firstly, it is the plug-in portion A which has a transverse y-axis extending transversely to the x-axis, by which the cross-section of the drawer 1 is divided into upper and lower regions having different surface dimensions. The second connection part B of the socket 1, which is connected to its plug part A, serves to connect the power cord 2. The connection part B is provided with the usual securing of the power cord 2 against pulling out, which is not shown. The connecting part B has the shape of a truncated pyramid and has ribs 4 on its surface for easier gripping.

The cross-section of the plug portion A of the drawer 1 is defined above and below the y-axis by the convex arcs K1 and K2, both convex arcs K1 and K2 being substantially circular arc segments. The convex arc K1, which extends above the dividing axis y, is curved slightly less than the convex arc K2 extending below the dividing axis y, which means that the radius of the upper convex arc K1 is greater than the radius of the lower convex arc K2. In the transition regions U between these convex arcs K1 and K2, the cross-section of the drawer 1 is defined by arcs of smaller radius. The dividing axis y lies at the junction of these transition regions U.

As can be seen further from FIG. 1, two receptacles 6 for the flat pins 12 and a receptacle 7 for the round pin 15 are embedded in the front side 5 of the drawer 1. The flat pins 12 have substantially rectangular cross-sections with longer sides extending parallel to the y-axis. In relation to the x-axis of symmetry, these flat pins 12 are arranged symmetrically, but asymmetrically with respect to the y-axis, i.e. they are displaced towards the more curved lower convex arc K2. Thus, the dividing axis y does not pass through the center of the cross-section · of the plug portion A of the drawer 1.

In this cross-section, the receptacle 7 for the round pin 15 is arranged between the receptacles 6 for the flat pins 12 and has a circular cross-section. The socket 7 for the round pin 15 is arranged such that the axis of symmetry of the socket 7 for the round pin 15 coincides with the x-axis of symmetry of the drawer 1 and the axis of symmetry of the socket 2 for the round pin 15 extends perpendicularly to the lower edges. beds 6 for flat dowels 12.

According to FIG. 3, electrically conductive clamping sleeves 8 are arranged in the receptacles 6 for the flat pins 12, to which the individual conductors of the power supply cord 2 are connected from the rear. The receptacle 7 for the round pin 15 is designed as a blind receptacle in the illustrated embodiment. electrically conductive since no protective conductor is used in this embodiment. However, in the design of the protective conductor socket 1, a correspondingly designed clamping sleeve can be arranged in the receptacle 2 for the round pin 15, which then constitutes a protective contact.

FIG. 2 shows a fork 9 of the electrical apparatus 10, which is embedded in this only schematically indicated electrical apparatus 10. This fork 9 of the electrical apparatus 10 comprises a fork seat 11 in which the flat pins 12, which represent contact pins, protrude freely.

The fork 9 of the electric apparatus 10 consists essentially of a housing 13 and a recessed fork portion 14 in this housing 13. This fork portion 14 is recessed relative to the front edge of the housing 13 which faces the outer wall of the electrical apparatus 10 so that the fork portion 14 is free The flat pins 12, which are arranged on the fork portion 14, protrude into this free space. The length of these flat pins 12 is smaller than the depth of the fork bed 11 measured in the same direction. the electrically conductive and, in the rear region of the fork portion 14, are connected to respective electrical connections which, within the electrical apparatus 10, lead to an electric motor or the like.

As can be seen in particular from FIG. 2, the plug 9 of the electrical apparatus 10, in particular its housing 13, has a cross-section corresponding to the cross-section of the socket 1. The internal walls of the housing 13 correspond to the circumference of the socket 1. the radii and the external dimensions of the drawer 1, so that the drawer 1 can be easily inserted into the fork receptacle 11.

Also in the case of the plug 9 of the electric apparatus 10, its cross-section consists of convex arcs K3 and K4 above and below the dividing axis y '. The upper cross-sectional area is defined by the convex arc K3, while the lower cross-section is defined by the convex arc K4. In this case too, the radius of the upper convex arc K3 is greater than the radius of the lower convex arc K4.

It can further be seen that, for both the socket 1 and the plug 9 of the electrical apparatus 10, the dimension between the transition regions U is clearly greater than the perpendicular largest dimension c of the cross section.

The aforementioned flat pins 12 are arranged in the fork receptacle 11 so that when the socket 1 is inserted into the fork receptacle 11, these flat pins 12 are inserted into the receptacles 6 for these flat pins and into the clamping tubes 8 located in these receptacles 6, thereby reaches electrical contact. This is evident from Figure 4.

It can also be seen from FIG. 4 that in the insertion direction r the measured length of the plug part A of the receptacle 1 corresponds in the same direction to the measured depth of the fork receptacle 11 so that only the connecting part protrudes from the fork receptacle 11 B sockets 1. This results in additional functions of both these parts A and B of socket 1. The plug portion A is the actual connecting region which serves to reach the plug connection. The connecting portion B serves as a handling area in which the socket 1 can be gripped and thus inserted into or pulled out of the plug 9 of the electrical apparatus 10.

If a socket and a plug with a protective conductor are required, the socket 1, as already mentioned, is provided in its receptacle 2 for a round pin 15 with a corresponding clamping sleeve. The fork seat 11 is then provided with a correspondingly oriented and executed round pin 15, which is shown in dotted lines in FIGS. 2 to 4.

FIGS. 5 to 10 show a second embodiment of a socket 21 which can be connected to a second embodiment of a plug 9 of the electrical apparatus 10 shown in FIGS. 11 and 12. This coupled state is shown in Fig. 13.

The female receptacle 1 in the second embodiment has a cross-section in its male part A which corresponds in its contour to that of the first embodiment. Here, too, there is a cross-sectional area above the dividing axis y which is defined by the convex arc K1. The cross-sectional area below the dividing axis y is defined by another convex arc K2 with a different radius. Here, the radius R1 of the upper convex arc K1 is also greater than the radius R2 of the lower convex arc K2.

In the illustrated embodiment, the radius R1 of the upper convex arc K1 is approximately 50 mm and the radius R2 of the lower convex arc K2 is approximately 37 mm - see FIG. 6. The transition regions U between the convex arcs K1 and K2 also have the shape of circular arc sections.

Furthermore, it follows from the geometrical conditions that the geometric center M1 of the convex arc K1 is located outside the cross-sectional area of the drawer 1, whereas the geometric center M2 of the convex arc K2 is situated inside the cross-sectional area. The two geometric centers M1 and M2 are on the x-axis of symmetry.

The unsymmetrical cross-section of the cross-section relative to the y-axis which is perpendicular to the x-axis of symmetry shows that the center of gravity F of the cross-sectional area does not coincide with the intersection of the x-axis of symmetry with the y-axis. In practice, this center of gravity F is located below the dividing axis y according to FIG. 6, i.e., it is shifted towards a more substantially curved lower convex arc K2.

It follows from the described geometrical conditions that the ratio of width to height of the cross-section of drawer 1 is approximately 17: 1. In the present embodiment, it follows that the cross-section dimension b between the two transition regions U is approximately 34 mm and mm.

As can further be seen from FIG. 8, the dimensions of the plug portion A of the drawer 1 are selected such that the length a of the plug portion A corresponds approximately to the width b of the cross-section of the plug portion A.

Unlike the first exemplary embodiment, the front plane of the receptacles 6 for the flat pins 12 is not located in the plane of the front side 5 of the drawer 1, but is displaced rearward in the retracting direction r. In this way, a cavity 16 is formed which is outwardly defined by the outer wall of the drawer 1. The depth of this cavity 16 is approximately 5 mm in the example shown. The flat pin receptacles 6 open into the bottom of this cavity 16 and have a rectangular cross-section. These rectangular cross-sections, in contrast to the first embodiment, are oriented so that their longer sides are parallel to the x-axis of symmetry, the ratio of length to width of these rectangular cross-sections being approximately 15: 10, i.e. approximately 8.5 to 5.5 mm. In the direction parallel to the dividing axis y, the spacing of the beds 6 for the flat pins 12 is approximately 9 mm, the beds 6 being arranged symmetrically with respect to the x-axis of symmetry.

As can be seen from FIG. 6, the flat pin receptacles 6 are arranged asymmetrically with respect to the y-axis, i.e., they are displaced towards the cross-sectional area defined by the more curved convex arc K2, such that is parallel to the dividing axis y, passing approximately the center of gravity F of the cross-sectional area of the drawer 1.

In the receptacles 6 for the flat pins 12, at a distance of approximately 9 mm from the bottom 17 of the cavity 16, clamping tubes 8 are fastened. As already mentioned in connection with the first exemplary embodiment, In the illustrated embodiment, however, the receptacle 7 for the round plug 15 is electrically non-conductive, i.e. designed as a blind bed. Also, this round pin receptacle 15 opens into the bottom 17 of the cavity 16, which is displaced towards the front side 5 of the drawer 1.

The socket 1 according to the second embodiment is additionally provided with a snap-in thumb 18 which protrudes from the periphery of its plug-in portion A. This snap-in thumb 18 is resilient in a direction perpendicular to the longitudinal direction of the receptacles 6 for the flat pins 12. In particular, the snap-in thumb 18 is arranged so as to be located on the outside of the plug-in portion A of the drawer 1, which is delimited by the upper convex arc to symmetrically with respect to the flat pin receptacles 6. the latch thumb 18 is located approximately in the middle of the length and plug portion A of the drawer

1.

This snap-in thumb 18 is spring-loaded by a compression spring 19 which is arranged in the plug-in portion A of the drawer 1 so that the snap-in thumb 18 can be fully pushed into the surface of the outer side of the plug-in portion A.

The arrangement of the snap-in thumb 18 on the upper side of the plug-in portion A of the drawer 1 and its approximately central location on this side provides the ergonomic advantage that the snap-in thumb 18 can be compressed with the thumb of the hand.

11 and 12 show a second embodiment of the fork 9 of the electrical apparatus 10. Also, this fork 9 consists essentially of a housing 13 and a fork portion 14.

In contrast to the first exemplary embodiment, there is a free protruding padding extension 20 upstream of the fork parts 14 in the retracting direction 20, on which the tabs 21 for the flat pins 12 are again arranged.

The inner walls of the housing 13 also correspond in this embodiment to the cross-section and dimensions of the drawer 1. The radius R3 of the upper convex arc K3 in Fig. 11 corresponds essentially to the radius R1 and the radius R4 of the lower convex arc K4 corresponds substantially to the radius R2 v ', which is perpendicular to the x-axis of symmetry, passes through the transition regions between the two convex arcs K3 and K4.

Said padding 20 has the same geometrical ratios, but on a reduced scale, so that between the padding 20 and the inner walls of the housing 13 there is an annular groove having an approximately constant width over the entire circumference. The cross-sectional dimensions of the infill extension 20 correspond to the dimensions of the cavity 16 of the receptacle 1 in the second embodiment, so that after insertion of the receptacle 1 into the fork receptacle 11 the filler extension 20 is fully inserted into the cavity 16.

The flat pin receptacles 21 are electrically nonconductive and have rectangular cross-sections adapted to the flat pin receptacles 6. The flat pins 12 extend from the fronts of these receptacles 21. In the transition region between the grip 21 and the flat pin 12, a centering projection 22 is formed on the grip 21 which, when the drawer 1 is inserted to center the flat pin 12, fits into a corresponding recess 23 in the partition 24 arranged between the flat pin receptacle 6 and the clamping sleeve. .8.

The length of the grips 21 measured in the insertion direction r corresponds approximately to the distance between the bottom 17 of the cavity 16 in the drawer 1 and the clamping tubes 8.

The plug housing 13 of the electrical apparatus 10 is provided with a leading chamfer 25 on the insertion side, which, when the drawer 1 is inserted, presses the snap-in thumb 18 against the compression spring 19.

The snap-in thumb 18 is located in the bore 26 in the housing 13 of the plug 9 of the electrical apparatus when the drawer 1 of FIG. 13 is inserted.

10. The snap-in thumb 18, which is pushed into the bore 26 by the compression spring 19, prevents the socket 1 from being unintentionally pulled out of the plug 9 of the electrical apparatus 10.

The disconnection of the described connection of the socket 1 to the plug 9 of the electrical apparatus 10 is only possible consciously in this embodiment. The fork 9 of the electric apparatus 10 is for this purpose provided with a push-button 27 which is formed on the plug side of the housing 13 in the region of its upper side, which is delimited by a less curved upper convex arc K3. For this purpose, a recess 28 is provided in the electrical apparatus 10 for the fork 9, which enables the actuation of said button 27. The transition region between the housing 13 and the button 27 is designed in a one-piece design to be resilient. . On the inside, the disengaging thumb 29 is formed on the button 27 downwardly, i.e. towards the bore 26 of the housing 13.

When the socket 1 is disconnected from the plug 9 of the electrical apparatus 10, the button 27 is depressed so that the button 27 is lowered together with the disconnecting thumb 29. The free end of the uncoupling thumb 29 in this case compresses the snap-in finger 18 against the action of the compression spring 19, so that the snap-in finger 18 is thus pushed out of the bore 26 in the housing 13. It is then possible to remove the socket 1 from the plug 9 of the electrical apparatus 10.

This embodiment of the anti-pull-out device is particularly desirable for electrical apparatuses 10 which move during their use, for example, vacuum cleaners, electric lawn mowers or the like. Using a socket connection without such a lock could inadvertently pull out the socket 1 during operation, which is undesirable for safety reasons.

14 to 16 show the socket 1 in the second embodiment in connection with the plug 9 of the electrical apparatus 10 in the third embodiment. This fork 9 differs from the above-described fork 9 in that no padding extension 20 is used here. The tabs 21 of the flat pins 12 are instead arranged directly on the fork portion 14 of the fork 9. These lugs 21 are extended by the length of the padding extension 20, so that after insertion of the socket 1 into this plug 9 of the electrical apparatus 10 according to FIG. 16, the same ratios as in the above-described embodiment according to FIG. 13 are achieved. However, here the socket 1 abuts the fork portion 14 of the plug 9 only by its front 5, it has only a ring shape in connection with the embodiment of the cavity 16.

17 to 19 show another third embodiment of the drawer

1. This third embodiment differs from the second exemplary embodiment in the design of the spring-loaded snap-in thumb 18. There is no compression spring applied to press the snap-in thumb 18. Instead, a snap-in finger 18 is provided with a resilient snap-in finger 18. an arm 30 which is freely cut into the housing of the plug portion A of the drawer 1. The snap-in thumb 18 is formed directly on this spring arm 30. The resilient deflection of the spring arm 30 with the snap-in thumb 18 in the direction of compression of the snap-in thumb 18 is allowed by the clearance 31 below the spring-loaded arm 30.

The socket 1 is further provided with an operating pin 32 having a circular cross-section, fixed in the bottom 17 of the cavity 16 and extending over the front side 5 of the drawer 1. The operating pin 32 is arranged centrally between the flat beds 6 pins 12, approximately at the intersection of the x-axis of symmetry with the y-axis. By means of this control pin 32, a switch or the like can be operated, which can be arranged in the region of the fork portion 14 of the fork 9 and can serve to send a pulse or to switch on or off various electrical or electronic circuits.

All the features described are important to the invention. The scope of the present invention is also intended to fully encompass the contents of the respective priority applications, the features of which determine the scope of the claims of this application.

Represented by:

Ing.J.Chlustina

13.08.97 &>. SW4>

Claims (9)

PATENT CLAIMS An electrical appliance receptacle having at least two flat pin receptacles, the receptacle being non-circular in cross-section perpendicular to the insertion direction and symmetrical to the symmetry axis extending transversely to the larger transverse dimension of the receptacle, characterized in that transverse to the (x) symmetry axis the dividing axis (y) extends and the cross-section of the drawer (1) above and below this dividing axis (y) is delimited by convex arcs (ΚΙ, K2), the two convex arcs (ΚΙ, K2) having essentially the shape of segments of circular arcs and different radii (R1, R2). Socket according to claim 1 or in particular according to this claim, characterized in that the cross-sectional dimension (b) of the socket (1) between the transition regions (U) connecting different convex arcs (ΚΙ, K2) is significantly larger than the largest perpendicular dimension (c) of this cross-section. Socket according to one or more of the preceding claims or in particular according to these claims, characterized in that the receptacles (6) for the flat pins (12) are arranged asymmetrically with respect to the dividing axis (y) between the transition regions (U) and to a cross-sectional area delimited by a more curved convex arc (K2). Socket according to one or more of the preceding claims or in particular according to these claims, characterized in that it has a snap-in thumb (18) protruding from its periphery which is springed perpendicularly to the longitudinal direction of the receptacles (6) for the flat pins (12). . Socket according to one or more of the preceding claims or in particular according to these claims, characterized in that the snap-in thumb (18) is arranged on the less curved outer side of the drawer (1). Socket according to one or more of the preceding claims or in particular according to these claims, characterized in that the snap-in thumb (18) is arranged approximately midway between the receptacles (6) for the flat pins (12). Socket according to one or more of the preceding claims or in particular according to these claims, characterized in that, in the cross-section of the drawer (1), a socket (7) for a round pin (15) is arranged between the receptacles (6) for the flat pins (12). . Socket according to one or more of the preceding claims or in particular according to these claims, characterized in that, in the design of the socket (1) without protective contact, the receptacle (7) for the round pin (15) is non-conductive. 9. A plug for an electrical appliance with a fork receptacle and a receptacle adapted thereto, the fork receptacle and the receptacle being non-circular and symmetrical to the axis of symmetry extending transversely to the largest dimension of this cross-section, characterized in that orthogonal to the axis (x) ', x) the symmetry runs through the dividing axis (y', y) and the cross-sectional areas above and below this dividing axis (y ', y) are delimited by convex arcs (K3, K4; ΚΙ, K2), both convex arcs (K3, K4, · ΚΙ, K2) have essentially the shape of segments of circular arcs with different radii (R3, R4; R1, R2).