ES2745198T3 - Socket - Google Patents

Abstract

A socket base (100) comprising socket base terminals (111, 112), a cover (120) with a cylindrical well face (130) for receiving a socket (200) and comprising at least two holes for contact (121) adapted to receive contact pins (211) of said plug to transmit electrical energy thereto, in which each contact hole (121) is located at the bottom of a concave contact pin guide ( 141, 142), said contact holes (121) and contact pin guides (141, 142) being arranged on a pressure plate (140), wherein said pressure plate (140) is configured to move axially along the well face (130) between an outer position, in which the pressure plate is pushed outwards by a spring (145), and an inner position, in which the contact pins (211) and the ground contacts (212, 250) in the socket (200), said socket (200) being in inserted into the socket base (100), they are electrically connected to their respective socket base terminals (111, 112), characterized in that the pressure plate (140) can rotatably move about an axis of rotational symmetry ( z) of the cylindrical well face (130) between a first orientation where the contact holes (121) are angularly offset from the terminals (111) and a second orientation where the contact holes (121) are angularly aligned with the terminals (111), in which the cylindrical well face (130) has axial ribs (131) directed radially inward, in such a way that the pressure plate (140) can slide in a rotary manner on them.

Description

DESCRIPTION

Socket

Background

Field of the Invention

The present invention relates to contacts for connection to a power supply network, in particular to a plug base with the facilitated input of a plug.

Prior and related technique

A mobile electrical equipment generally has a power cable with a plug, and is connected to a power supply network by inserting the plug into a plug base, which is permanently connected to the power supply network. Currently, about 20 such connections are used in different countries. Common to all, the terminals with active voltage are available through contact holes in the plug base, and that the plug has protruding contact pins that fit into the contact holes. The shape of the contact pins and their corresponding contact holes vary. For example, blade-shaped contact pins are used in the United States, while cylindrical contact pins are common in Europe. Some contacts are polarized, that is, certain contact pins must be connected to certain current conducting wires indicated as line (L) and neutral (N). Other contacts are not polarized, in which it is irrelevant which contact pin is connected to the current conductor cable L or N. Both polarized and non-polarized contacts can be grounded or ungrounded. This description refers to a grounded plug base, which has terminals connected to electric ground (ground) in addition to the current conductive terminals for the plug's contact pins. Because the ground terminals are at a fixed ground potential and, consequently, do not transmit electrical power during normal operation, the ground terminals may be exposed in the plug base. Ground terminals may also have a different design in different countries. For example, a spring-loaded ground clip adapted to a groove in the plug is common in Germany and in several other European countries, while a ground pin adapted to a hole in the plug is common in France.

In order to facilitate the sale of electrical appliances, and to make it convenient for travelers to carry electrical appliances with them from one country to another, an electrotechnical equipment, which includes plugs and plug bases, is becoming increasingly standardized. The United States International Trade Administration (ITA) has awarded the letters A-N to the most common connections, and a European standard, the certification of electrotechnical equipment (EEC), applies to electrotechnical equipment in most of Europe. For example, most electrical appliances in Europe, except Great Britain and Ireland, are delivered with a grounded plug of the CEE 7/7 type, which is included in the F type of the ITA. This plug is used as an example below. A person skilled in the art can, without inventive effort, adapt the example to other types of contacts. Other types of contact will also be described when relevant.

Specifically, Figures 1a and 1b illustrate a plug 200 of CEE 7/7 type, which is a hybrid between a German and a French standard. The original German plug is standardized as CEE 7/4 ("Schuko") and defines two cylindrical contact pins with length L = 19 mm, diameter d = 4.0 mm and distance S = 19 mm between the central axes as shown in figure 1a. The CEE 7/7 defines a plug with dimensions slightly different from those shown in Figure 1a, but the plug base according to CEE 7/7 receives both new plugs of the CEE 7/7 type and older plugs of the CEE 7 type /4.

Figure 1b shows the plug in Figure 1a seen from below. In this case, a hole 250 adapted to a ground pin of the French standard can be seen. A metal sleeve inside the hole 250 is connected to a metal plate in the groove 212 from the German CEE 7/4, and then to a ground wire in the power cable of the apparatus. The maximum diameter a for the plug, the sizes b, c for a guide tip 232 and other measures are found in CEE 7/7.

It is not practical to have to change the plug in lamps, ovens and other electrotechnical equipment in order to adapt the equipment to the invention. Because the European electrotechnical equipment is delivered with a plug of the type illustrated in Figures 1a and 1b, an objective of the present invention is that a European implementation must be able to receive plugs of the EEC type 7/7 and the like, but not necessarily all the plugs that can be received in a socket of type c Ee 7/7. In general, it is an objective that the plug base according to the present invention should be able to receive a plug of the type that is delivered with the equipment sold for domestic use, usually for a mains voltage of 110 V or 220-240 V.

Figure 2a shows a schematic section through a commercially connected grounded plug base 10 for the plug shown in Figures 1a and 1b. The illustrated variety has a cover that rests on a wall surface 15 and semicircular grooves 14 (see Figure 2b) in order to guide the pins of contact of the plug towards the contact holes 121. The plug base 10 has a well with a depth less than the length of the contact pins in the CEE 7/7, that is, h <19 mm. Therefore, the contact pins 211 (Figure 1) can slide in the lower face of the well and / or in the guides 14 until they hit the holes 121, and then the plug can be pressed down until the contact pins hit terminal 111, which are different terminals L and N in a polarized contact. These terminals 111 are connected to the power supply network, which in this example has 220-240 VAC and delivers a current of up to 16 A. A radially pushed earth clip 112 is connected to a ground wire in the network of energy supply. The electrical terminals L, N and the earth are connected to wires and placed in a wall box 11 in a known manner.

Figure 2b shows the plug base in Figure 2a seen from above. The circle drawn with a dotted and striped line corresponds to the section through the pressure plate shown with a dotted and striped line in Figure 2a. Therefore, the edge of the wall box 11 can be seen. The semicircular grooves 14 serve to guide the contact pins of the plug towards the holes 121 and, therefore, are deeper in the holes 121 and shallower towards their extremes Similar grooves are found in some commercially available plug bases, for example, in the Elko 1091 model. The ground clips 112 are shown schematically and pushed radially inward, so that they engage firmly in the grooves of ground in a plug inserted into the socket base.

The guides 14 shown in Figures 2a and 2b guide the contact pins towards the contact hole 121, but it can still be difficult to align the contact pins, especially if the plug base is in a place where the contact holes are not they are visible, or for people with reduced vision or functional abilities. Therefore, plug bases with larger and deeper contact pin guides are provided, which guide the plug contact pins towards the contact hole in the plug base.

US 1812 343 A discloses a plug base with a short and long guide groove that guides the contact pins in a plug to the respective openings in the plug base when the plug is pressed against it. At the same time, this causes the plug to rotate with respect to the plug base.

Document DE 653597 C discloses a similar plug base with two opposite, semicircular concave faces that are inclined in opposite directions towards the respective contact holes such that the contact pins slide towards the contact hole, and the plug rotates consequently, when the plug is pressed against the plug base.

Document DE3731588 A1 discloses a plug base comprising a spring-loaded cover plate that protects the connector from dust.

Document DE 2457072 A1 discloses a grounded electrical socket base with concave contact conductors as described above. This plug base is further developed with a base plate that can move axially in the direction of the contact pins disclosed in DE 270 1 188 AI against a spring force. The latter is considered the closest state of the art.

WO2005 / 025012 A1 discloses a plug base comprising an electrical terminal receptacle that can move within a body. The receptacle is releasably retained in a first position as long as no plug is inserted into the plug base.

Document US2006 / 172583 A1 discloses a plug base to receive a plug.

Document FR 2840117 A1 discloses a plug base comprising a removable mechanism with a fixed and movable section, such that the plug base slides between two positions. When the plug is in place, the plug base is pushed towards the wall, hiding the plug.

EP 2456021 A1 discloses a plug base that includes sliding mobile side posts. Some countries, for example, Denmark, Finland, Norway and Sweden, require that the plug bases have a child safety device, that is, equipment to prevent children from coming into contact with the power supply network. The child safety device is normally a cover over the contact holes and / or a device that requires that the contact pins can only be inserted if they are pressed against both contact holes simultaneously.

Existing exits can be mounted entirely on the outside of a wall, or they can have permanent connections to the power supply network in a box embedded in the wall, and only one cover on the outside of the wall. In both cases, there is a desire to adapt a plug base in an existing installation. Therefore, the aim of the present invention is to provide a plug base that meets at least one of the above needs, and that retains the advantages of the prior art.

Summary of the invention

This objective is achieved with a plug base according to claim 1.

In particular, the invention provides a plug base comprising a cover with a cylindrical well face to receive a predefined plug and comprising at least two contact holes adapted to receive contact pins of said plug to transmit electrical power thereto. , in which each contact hole is located at the bottom of a concave contact pin guide. The contact holes and the contact pin guides are arranged in a pressure plate, which can move axially along the well face between an external position, in which the pressure plate is pushed out by a spring , and an inner position, in which the contact pins and the ground contacts in the plug inserted in the plug base are electrically connected to their respective terminals adapted for a fixed connection to a power supply network. The pressure plate can rotatably move around an axis of rotational symmetry (z) of the cylindrical well face between a first orientation where the contact holes are angularly offset from the terminals and a second orientation where the contact holes are angularly aligned with the terminals.

The existing predefined plug is preferably of a type that is delivered with an electrotechnical equipment in a region, for example the CEE 7/7 type in Europe or in a corresponding grounded plug in other parts of the world. The contacts in the plug comprise contact pins and ground contacts.

When the pressure plate is in its outer position, the contact pins can slide freely in the contact pin guides without being clogged by the ground terminals on the plug base. When the contact pins have entered the contact holes, the plug is oriented and can move axially over the ground terminals. The axial thrust out prevents the pressure plate from moving to its inner position while the contact pins are pressed against the bottom of the concave contact pin guides. This makes it easier for people with reduced functional capabilities to insert a grounded plug into a grounded plug base.

When the terminals are connected to a power supply network, the electrically conductive terminals transmit electrical power to the contact pins, and one or more ground terminals connected to a ground wire in the power supply network connect the or earth contacts of the plug with the potential of electrical ground. The terminals can be mounted in a connection box from a previously installed socket base, such that only the former is replaced with the cover according to the invention, which has an axially movable pressure plate. Alternatively, the terminals can be mounted in a junction box as part of the plug base, so that the new terminals must be connected to the power supply network in a known way. In both alternatives, the terminals are adapted for a fixed connection to the power supply network. This facilitates the adaptation of the invention in an existing installation. In addition, costs are reduced if the cover can be adapted to a previously installed junction box.

The angular displacement makes it possible to prevent an object inserted in the contact holes from hitting the terminals that transmit the current and voltage, and therefore acts as a safety device for children. Each contact hole preferably leads to a tunnel that extends axially in an elongated body. If a child inserts an electrically conductive rod into the contact hole and swings the rod from side to side, the angular amplitude is limited by the tunnel openings to the arctan (D / Lt), where D is the cross section plus Large contact hole and Lt is the length of the tunnel. For example, the maximum angular amplitude decreases from approximately 70 ° for a contact hole through a plate with a thickness Lt = 0.5D to less than 30 ° if the tunnel extends to Lt = 2D. This reduces the risk of injury to a child and, therefore, increases safety.

In a preferred embodiment, the pressure plate is held in its inner position by a radially directed element. This prevents the pressure plate from moving out and pulling the plug, and becomes more important with an increasingly powerful push on the pressure plate. The radially extending member may be a fixed rib, specifically if the thrust is large.

In some embodiments, the radially directed element is pushed radially inwardly from the cylindrical pit face. When the pressure plate has forced said element radially towards the well face and has passed a certain axial position, the pushed element moves inward on the upper side of the pressure plate and remains in its inner position. This can provide a tactile feedback to the user indicating that the plug is inserted correctly. When the plug is removed, the pushing force of the radial fasteners must be exceeded without removing the plug from the pressure plate.

In an alternative embodiment, the tunnel in the elongated body comprises an electrically conductive sleeve connected to a sliding power supply contact displaced from the contact hole. When the pressure plate with the contact holes is in the outer position, the sleeve is insulated from the sliding contact so that the child with the rod does not engage the active wires even if the child touches the electrically conductive sleeve. When the pressure plate is in its inner position, the sliding contact is closed in such a way that electrical voltage is transmitted to the contact pins through the electrically conductive sleeve. An electrically conductive sleeve can hold the contact pins similarly to the sliding contacts on a traditional plug base, and can possibly be adapted in such a way that the pressure plate is removed along with the plug in embodiments with pushed fasteners radially

The safety of children can be further improved by directing the contact holes (121) in the outer position towards an electrically insulating element placed behind the pressure plate. In embodiments where the pressure plate only moves axially, a prior art child safety device can be used. The insulating elements are plates that can only be removed from the contact holes when two contact pins are pressed against them simultaneously. In embodiments where the pressure plate rotates around the central axis between the outer and inner position, an insulating sleeve can be mounted, for example in the extension of an elongated tunnel. The rotation movement during insertion of the plug will move the contact hole from the insulating sleeve to an active terminal.

A truncated conical guide face is preferably disposed between an upper face of the lid and the cylindrical well face. This transition acts as a funnel and guides the plug towards the well and the pressure plate. Therefore, the insertion of the plug is further facilitated.

Other features and advantages of the present invention appear in the dependent claims and in the following detailed description.

Brief description of the drawings

The invention will be described in greater detail below by way of exemplary embodiments with reference to the accompanying drawings, in which:

Figure 1a illustrates a known plug that can be used with the present invention;

Figure 1b shows the plug in Figure 1a seen from below;

Figure 2a is a schematic section through a known grounded plug base;

Figure 2b shows the plug base in Figure 2a viewed from above;

Figure 3a shows a plug inserted in a plug base according to the invention;

Figure 3b shows an embodiment of a pressure plate for use in the invention;

Figure 4: is a perspective view of a preferred embodiment;

Figure 5: shows a detail of Figure 4;

Figure 6: is a top view of the preferred embodiment with the pressure plate in its outer position; Figure 7: is a first schematic section through the embodiment in Figure 6;

Figure 8: shows the embodiment in Figure 6 with the pressure plate in its inner position; Y

Figure 9: is a second schematic section through the embodiment in Figures 3-8.

Detailed description

Figures 1 and 2 illustrate the prior art, and have been described above.

Figure 3a illustrates a plug 200 inserted into a plug base 100 according to the invention. In this example, the plug 200 is of the CEE 7/7 type, and the plug base 100 is adapted to this plug and the compatible types.

The illustrated embodiment of the plug base 100 is configured for wall mounting, and therefore comprises a connection box 110 that fits into a conventional wall box 11 (Figure 2a), and a cover 120 that covers the box wall. The opening 113 is for a power supply network cable, in this example a cable with a ground wire and the conductors L and N as in Figure 2a. These must be electrically connected to the electrotechnical equipment through a power cable (not shown) through the opening 202 in the plug 200.

For ease of description, an imaginary central axis z passes through the plug base 100. This x-axis is coaxial with the axis of rotation of a cylindrical pit face 130 with a diameter greater than a cylinder wall or casing cylinder 230 around the plug. In this description, the terms "axial" and "radial" refer to the central axis z. Therefore, when the plug is inserted, as in Figure 3a, the cylinders 130 and 230 extend coaxially around the central axis z, and both contact pins and all ground contacts in the plug are directed axially.

A truncated conical transition 123 guides the plug into the well bounded by the well face 130 when the plug is inserted.

An electrical ground potential is transmitted through two diametrically opposed earth fasteners 112 (not shown in Figure 3a) to complementary ground grooves 212 in the plug. For this, the ground clips are pushed radially inwards towards the central z axis, and slide along the axially directed groove 212 when the plug 200 is inserted or removed. The contact pins in the plug ( not shown) slide similarly along the complementary sliding terminals. What is referred to as axial displacement herein, therefore, is generally used to provide an electrical contact between the complementary contacts in the plug and the terminals within the plug base, for example, the ground clip. ground groove and contact pin / sliding terminal. As can be seen, the contact plugs for electric cables extend from the plug, but the plug base can also have a ground contact pin that is inserted into a sliding contact (250 in Figure 1b) by axial displacement.

The casing cylinder 230 of the plug is broken by a control surface 231 that extends axially and parallel to the axis through diametrically opposed grooves 212. If desired, a corresponding face can be provided in the basehole of plug, for example, in order to adapt to certain standards. However, in principle, any cylindrical face 230 of which a part 231 is cut fits into a cylinder face with a larger diameter. Therefore, the well in the plug base 100 is represented as a straight cylinder without control faces adapted to local standards.

The guide rib 232 of the pin 200 may have a corresponding groove in the socket of the plug base, but again this is an adaptation understood by the invention. While the outer face of the control rib 232 rests on or inside the casing cylinder (the imaginary one) that extends from the face 230 in the plug, the plug 200 can be inserted into a cylindrical bore with a larger diameter.

Figure 3b illustrates a pressure plate 140 for use in the invention. The pressure plate 140 can generally move axially along the well face 130 in the plug base 100, and for this it can have radially directed lugs 143 that fit into the corresponding grooves in the cylinder wall 130 and / or in the radially directed grooves 144 adapted to the elements projecting radially inwardly from the cylindrical well face 130 in various embodiments. For example, the ground clips 112 may pass through the grooves 144 in the pressure plate as the pressure plate 140 moves axially in the plug base 100. Therefore, in general, the guide elements radially directed such as lugs 143 and / or grooves 144 are distributed along the circumference of the pressure plate 140.

In this example, the pressure plate 140 has axially directed the contact holes 121 for two cylindrical contact pins in an CEE 7/7 type plug. The contact holes 121 are located at the bottom of the concave contact pin guides 141 and 142, which have the same function as the semicircular guides 14 shown in Figure 2b. Therefore, the concave contact pin guides 141 and 142 guide the contact pins 211 towards the contact holes 121 when the plug 200 is axially pressed against the pressure plate 140 in the direction towards the paper plane in the figure 3b This applies regardless of where or how the contact pins engage with the pressure plate 140. The plug 200 will rotate around the central z axis when the contact pins slide along the bottom of the pin guides. contact 141 and 142.

Figure 4 shows the pressure plate 140 with the contact pin guides 141 and 142 in an inner position. The pressure plate has an outer position, in which the ground terminals, such as the ground clips 212 and a ground pin (not shown) adapted to the ground hole 250 in Figure 1b, are totally or partially hidden. Therefore, in the outer position, the contact pins can slide unimpeded through the ground terminals along the bottom of the concave contact pin guides 141 and 142 towards the contact holes 121. In one contact polarized, the ground element advantageously protrudes some of the pressure plate in the outer position, such that the contact pins are guided to their respective terminals L and N. For example, the ground pin in a polarized French contact protrudes something along the upper face of the pressure plate when it is in its outer position. When the contact pins are inserted into the contact holes 121 by the contact pin guides 141 and 142, there are two possibilities. Or, the contact pins are oriented correctly, so that the ground pin slides in the ground hole 250, or the orientation is incorrect, such that the ground pin prevents further axial movement of the plug 200 In the latter case, it is sufficient to remove the plug a short distance, correct the orientation (rotate the plug 180 ° around the central axis in this example) and insert the contact pins in the contact holes with the correct orientation. In a non-polarized contact, such as the "Schuko" contact in this example, the orientation of the contact pins is indifferent and, therefore, both possible orientations are the correct orientation.

When the contact pins are inserted into the contact holes 121 in the correct orientation, the pressure plate moves together with the plug to the inner position shown in Figure 4. Preferably, this Inner position can only be reached when plug 200 is inserted, and Figure 4 shows the pressure plate in its inner position simply for illustration. As shown in Figure 4, the pressure plate is guided axially along a ground clip 112, which is thus electrically connected to the groove 212 in an inserted socket. Similarly, an axial displacement will insert an axially directed ground pin into a complementary hole, hole 250 in Figure 1b in this example, into a properly oriented polarized plug.

The pressure plate 140 with the contact pin guide 142 can move axially along the ground clip 112. Therefore, the ground clip 112 can also serve as an axial guide for the pressure plate. In order to prevent the pressure plate from pivoting about the axis between the diametrically opposed ground clips 112, the pressure plate may advantageously be provided with guide walls (not shown) extending parallel to the sides of the clip of land 112.

The pressure plate 140 must be able to withstand a certain axial force in its outer position such that the contact pins can slide along the concave contact pin guides 141 and 142 without causing the pressure plate to move to the inner position shown in figure 4. Therefore, the pressure plate is pushed out by a spring when it is in the outer position. In order to keep the pressure plate in its inner position, radially directed retaining elements, represented in Figure 4, by the ground clip 212 and a ball 146 can be mounted, both being pushed radially inwards by a spring force. When the plug is inserted, the radial thrust forces must be overcome before the retaining element snaps into place on the pressure plate. The user holding the plug 200 can feel more or less clearly that such an element, for example the ball 146, fits into position. With a sufficient radial thrust, the user receives a different tactile feedback when the pressure plate is in its internal position and, therefore, the plug is fully inserted.

Figure 5 shows the detail surrounded in Figure 4. The cover 120, the conical guide 123, the pit face 130 and the concave contact pin guide 142 are recognized in Figure 4. The ground clip 112 is elastic and it is pushed radially inwards. When the pressure plate moves axially along the well face 130, the ground clip 112 is pushed radially outward in a recess 114 in the cylindrical well face. When the pressure plate has passed and is in its inner position, the ground clip 112 is coupled to the pressure plate and thus exerts an axial force on the pressure plate that helps keep the pressure plate in position. inside shown in Figure 4. It is understood that the ball 146 in Figure 4 can move radially outward in a similar manner, and that a suitable number of radially pushed elements 112, 146 can collectively exceed the spring force necessary to hold the plate pressure in its outer position while the contact pins slide into the contact pin guides 141, 142 when the plug is inserted. In such an embodiment, the pressure plate must be provided with fasteners or the like, so that they can be removed together with the plug. An electrically conductive sleeve mounted in the contact hole can act as a fastener around the contact pins in the plug, and is described in more detail below.

Figure 6 shows a preferred embodiment, in which the pressure plate with the contact pin guides 141, 142 moves angularly in relation to the cover 120. In this example, the axis 122 through the centers of the holes of contact 121 is rotated 30 ° clockwise around the central axis z with respect to the lower edge of the cover 120. The angular displacement is preferably sufficient to ensure that the contact holes 121 are not aligned with the AC terminals behind the cover 120, but the 30 ° angle shown is randomly selected. In this embodiment, the pressure plate 140 acts as a child safety device in the sense that an object inserted axially through a contact hole 121 does not engage an active terminal, that is, one of the terminals of L or N power transmission.

Figure 7 is a section along the plane VII-VII in Figure 6, that is, through the center of a contact hole 121 seen along the axis through the centers of the contact holes. The cover 120 is cut as in Figure 2a. The plug base 100 is mounted on a wall surface 15, and the connection box 110 is adapted to a conventional wall box 11 embedded behind the wall face 15 in a known manner. The connection box 110 contains contacts or sliding sleeves for the contact plugs connected to the AC terminals L and N as in Figure 2a. Normally, the connection box 110 and the cover 120 are delivered as a unit. However, it is possible to manufacture a cover 120 with an axially movable pressure plate adapted to an existing connection box.

In Fig. 7, the pressure plate 140 is in its upper position in the lower part of the truncated conical guide face 123. The guide face 123 and the concave contact pin guide 141 on the pressure plate 140 are configured to guiding a contact pin towards the contact hole 121. The section shows the rear end of the other contact pin guide 142, which guides the second contact pin towards a similar contact hole hidden behind the illustrated contact hole 121.

From Fig. 7, it is evident that the contact hole 121 is not aligned with the contacts or sleeves of slip that conduct current L and N. In addition, the contact hole in the bottom of the concave contact pin guide 141 opens to an elongated tunnel. In reality, the tunnel is just an extension of a short cylindrical contact hole 121 through the pressure plate. An elongated object inserted through the elongated tunnel shown 121 can move laterally less than a similar object that can freely rotate around the center in a hole in a thin plate. More specifically, the angular amplitude is limited by the openings of the tunnel to the arctan ( D / Lt), where D is the largest cross section of the contact hole and Lt is the length of the tunnel. For example, the maximum angular amplitude decreases from approximately 70 ° for a plate having a thickness Lt = 0.5D to less than 30 ° with a tunnel length Lt = 2D. This reduces the risk of a child inserting an object through the hole 121 from the outside, and thus accidentally making contact with one or both current conductive terminals L and N. If desirable, the connection box 110 may be provided with an electrically insulating blocking element (not shown) in the extension of the hole or tunnel 121 in Figure 7, such that it is impossible to insert an object into the hole before the pressure plate 140 is rotated around the central axis z, and the hole 121 thus moves from the locking element.

In Fig. 7, a ground bar connected to the ground clips 112 is shown mounted on a cylindrical pin 115 on the central z axis.

The ground bar can be fixed with respect to the pit face 130 in a traditional plug base. A similar plug is used in traditional plug bases and, therefore, it is possible to manufacture a cover according to the invention with a ground plug that is fixed in a ground hole in an existing installation.

Alternatively, the ground bar can be attached to the pressure plate 140, and the cylindrical pin 115 can still be inserted into an existing junction box. In this embodiment, the cylindrical pin 115 functions as a shaft for rotation around the central z axis, such that a ground pin for a polarized plug (hole 250 in Figure 1b) is fixed relative to the plate pressure 140, and thus can protrude along the pressure plate as described above.

The pressure plate 140 is pushed radially outward, that is, in the z direction, by a spring 145. In the embodiment in Figure 7 and in an embodiment in which the pressure plate only moves axially, the spring 145 must have sufficient rigidity to return the pressure plate 140 in the upper position, but without a rigidity large enough to force the plug 200 out of the socket base. The spring 145 may be one or more spiral springs. However, in embodiments where the pressure plate 140 can rotate around the z-axis, the spiral springs would require a separate sliding connection, while the leaf springs and the disk springs have a face along which the slide can slide. pressure plate. Therefore, the spring 145 is schematically shown as a curve, which preferably represents a leaf spring or a disk spring. In particular, it is noted that said leaf spring or disk spring can be fixed in a medium plane for axial movement. When the pressure plate 140 passes the middle plane, such a leaf spring or disc spring will bend in an opposite direction, and thereby push the pressure plate inward, towards the electrically conductive contacts L and N. This can be useful if the plug is connected to the pressure plate.

Figure 8 corresponds to Figure 6, but the pressure plate is rotated such that the axis 122 through the centers of the contact holes 121 extends parallel to the edge of the cover, and aligns with the conductive contacts below. The top plate also moves to the inner position, so that the ground clips 112 can be seen.

Figure 9 is a section through the plane IX-IX in Figure 8, that is, centrally through the socket base along the axis 122. The top plate 140 is in its inner position, and the holes of Contact 121 are aligned with their respective sliding terminals in the connection box 110. It is understood that a power supply cable is inserted through the wall box 11 and the hole 113 in the connection box for a connection electrical as illustrated in figure 7, but not shown in figure 9.

The rotation of the pressure plate 140 around the central z axis from the orientation shown in Figures 6 and 7 to the orientation shown in Figures 8 and 9 has aligned, as noted, the contact holes 121 with their respective contacts of sliding in the connection box. Such a rotation is practically allowed by providing the cylindrical face of the well with axial ribs 131 directed radially inwardly, such that the upper plate 140 can slide thereon. The rotation can be stopped by a radially directed element, for example, a wall or a groove 13 as shown in the traditional plug base illustrated in Figure 2b. In the present example, the slot 13 can be adapted to the nose 232 in the plug 200 shown in Figure 3a. The ground clip 112 and the top of the groove for the rib 232 are 90 ° apart, and if desirable they can serve as a support for the top plate 140 instead of, or in addition to, the separate ribs 131 on the walls of cylinder.

The rotation is preferably less than the angular distance between the ribs and other radially directed elements. In the present example, the rotation is 30 ° around the z axis. Figure 9 indicates 8 elements that extend radially with a distance of 45 ° between them, of which two ribs 131 can be seen, a ground clip 112 and two walls 13 in the figure. Provided that the rotation is less than the angular distance between the radially extending elements in the cylinder wall 130, no groove in the pressure plate 140 slides along any radially extending element before aligning on the ribs and the ground terminals, and therefore can move axially.

In Figure 9, the pressure plate 140 is rotated and moves axially inwardly along the ribs 131 from the position in Figure 7. The distance from the top of the pressure plate 140 to the contacts of sliding in the connection box in figure 9 is shorter than the contact pins in the plug, that is, less than 19 mm in the present example. This limits the length of the conical elements around the contact holes 121.

The spring 145 is compressed by the axial displacement of the pressure plate 140. The spring force is proportional to the compression and rigidity of the spring, and must be overcome by friction of the plug against the fixed parts of the plug base. Otherwise, the spring force will push the plug out of the socket base. In an alternative embodiment, the order of rotation and axial displacements can be interchanged. Then, when the plug is inserted, firstly the pressure plate 140 moves axially along the ribs 131, and then rotates under the ribs. Then, the spring force of the spring 145 can be increased because it forces the upper plate against the bottom of the axially directed ribs 131. When the plug is removed, the pressure plate is first rotated until the grooves in the pressure plate are aligned with the ribs 131, and the spring 145 contributes with a force that pushes the plug into the outer position.

In a variety, rotational and axial movements can be combined for helical movement. Next, the plug 200 is rotated about the z axis while the contact pins slide along the surfaces of the channels 141 and 142 towards the contact holes 121 as described above, and then axially slides in the holes 121. The rotational and axial movement of the pressure plate 140 then follows essentially in the same direction.

In yet another variety, the sliding contacts 111, which in FIG. 9 are represented as cylinders, the edge contacts, and the contact holes 121 have electrically conductive sleeves inside. These sleeves preferably hold the contact pins when the plug is inserted, such that the pressure plate is pulled when the plug is removed. When the pressure plate is in its outer position as in Figures 6 and 7, there is no electrical contact between the electrically conductive faces within the contact holes 121 and the active wires.

It is recognized that any contact that connects the contact holes to their respective conductive terminals in the inner position and that breaks the connection in the outer position can be used in a plug base with an axial movement. Similarly, a contact that is closed or broken by a rotation should be used in varieties with a pressure plate that is rotated around the z axis. An axial movement combined with a rotation in a freely selected order can thus provide an electrical contact between the electrically conductive faces in the contact holes 121 in the upper plate 140 and the sliding contacts 111 permanently connected to the supply network. energy, even when the sliding contacts 111 are cylinders not axially directed at the extension of the holes 121 as shown in the drawings.

The invention is described by referring to an example of a plug base for a plug of a certain type, but the scope of the patent is defined by the following claims.

Claims (8)

1. A plug base (100) comprising plug base terminals (111, 112), a cover (120) with a cylindrical well face (130) for receiving a plug (200) and comprising at least two contact holes (121) adapted to receive contact pins (211) of said plug for transmitting electrical power thereto, in which each contact hole (121) is located at the bottom of a contact pin guide concave (141, 142), said contact holes (121) and the contact pin guides (141, 142) being arranged in a pressure plate (140), wherein said pressure plate (140) is configured to move axially along the pit face (130) between an outer position, in which the pressure plate is pushed out by a spring (145), and an inner position, in which the contact pins (211 ) and the ground contacts (212, 250) on the plug (200), said plug (200) being inserted in the plug base (100), they are electrically connected to their respective plug base terminals (111, 112), characterized in that the pressure plate (140) can rotatably rotate about an axis of rotational symmetry ( z) of the cylindrical well face (130) between a first orientation where the contact holes (121) are angularly offset from the terminals (111) and a second orientation where the contact holes (121) are angularly aligned with the terminals (111), in which the cylindrical pit face (130) has axial ribs (131) radially inwardly directed, such that the pressure plate (140) can rotatably slide thereon. 2. The plug base (100) according to claim 1, wherein the pressure plate (140) is held in its inner position by a radially directed retaining element (112, 146; 131). 3. The plug base (100) according to claim 2, wherein the radially directed retaining element (146) is pushed radially inwardly from the cylindrical well face (130). 4. The plug base (100) according to any of the preceding claims, wherein each contact hole (121) leads to an axially extending tunnel in an elongated body (124). 5. The plug base (100) according to claim 4, wherein the tunnel in the elongate body (124) comprises an electrically conductive sleeve connected to a sliding power supply contact displaced from the contact hole (121) . 6. The plug base (100) according to claim 5, wherein the electrically conductive sleeve is adapted to hold a contact pin such that the pressure plate is removed along with the plug. 7. The plug base (100) according to any preceding claim, wherein the contact holes (121) in the outer position are directed towards an electrically insulating element placed behind the pressure plate (140). 8. The plug base (100) according to any preceding claim, further comprising a truncated conical guide face (123) between an upper face of the cover (120) and the cylindrical well face (130).