The object of the invention is a LED light and a LED tube used therein. Prior Art Fluorescent tubes have been used in different kinds of lamp solutions for decades. The installation method of the fluorescent tubes is standardized so that changing them would be possible also for the average consumer of electricity. In Fig. 1 a has been illustrated an installation method of a conventional fluorescent lamp 1 . Fluorescent lamp 1 comprises means for voltage feed 10, ballast 4, starter 5, fluorescent tube 2, contact pins 2a1 , 2a2, 2b1 , and 2b2 in the fluorescent tube, and fluorescent tube holders 3a and 3b in the framework of the lamp 1 (the actual light frame in not shown in Fig. 1 a). The fluorescent tube 2 is connected mechanically and electrically from its both ends to the holders 3a and 3b belonging to the light frame which holders have contacts for the contact pins 2a1 , 2a2, 2b1 , and 2b2 of the fluorescent tube 2.

Fluorescent tube 2 contains mercury which evaporates when heated with electrodes 2c and 2d at both ends of the fluorescent tube 2. The electrodes have been connected at contact pins 2a1 , 2a2, 2b1 , and 2b2 so that electric current can be led through them. When a fluorescent tube is started, the heating current is led from the means for voltage feed 10 via conductor 1 1 to the ballast 4. From the ballast 4 the current is led via conductor 12 through fluorescent tube's holder 3a to electrode 2c. In the starting stage of the fluorescent tube the current flows through the electrode 2c, and via holder 3a and conductor 13 to the starter 5. In the starting stage the starter 5 closes the starter circuit and the current flows via conductor 14 through holder 3b to the electrode 2d from which the current returns via holder 3b and conductor 15 back to the means for voltage feed 10. The current flowing in the resulting starter circuit heats up the electrodes 2c and 2d.

When the fluorescent tube 2 has started, the starter circuit opens up and the voltage received from the means for voltage feed 10 interacts between the electrodes 2c and 2d. In that case the current generating light flows through the fluorescent tube 2 between the electrodes 2c and 2d in mercury vapour. The installation method of a conventional fluorescent tube is user-safe. When changing the fluorescent tube 2 in lamp 1 , a situation with a danger of electric shock will not occur even if only one end of the fluorescent tube 2 were installed in the holder 3a or 3b in the frame of the light 1 . In such a situation the uninstalled end of the fluorescent tube 2 is always dead.

Fluorescent tubes, however, do contain mercury which is environmental toxin. Therefore, substitute solutions with lesser environmental impact have been searched for fluorescent tubes.

Fluorescent tubes can be replaced with a LED tube, for example, which is a structure with the appearance of a fluorescent tube, and inside of which there are several separate LEDs. In order to be able to use the existing frames of fluorescent lamps, two contact pins, which fit in the holders 3a and 3b of the fluorescent lamp 1 in Fig. 1 a, are also needed at both ends of the LED tube.

Fig. 1 b discloses one method to connect the LED tube 6 to the lamp 1 a. External voltage feed arrangement corresponds for the most part to the feed arrangement of a conventional fluorescent tube. However, the starter 5 has been removed and the conductors 13 and 14 belonging to the fluorescent lamp have also been disconnected. After disconnecting the conductors 13 and 14, an average user can no longer use a conventional fluorescent tube in lamp 1 b but it is only possible to use a LED tube.

LED tube 6 includes a circuit board or a substrate 6b to which several separate LED light sources 6c have been attached. The circuit board or substrate 6d can further include voltage converter circuits and control circuits required by the LEDs 6c. Alternatively, they can be on a separate circuit board (not illustrated in Fig. 1 b). The voltage feed has been arranged via the holders 3a and 3b at both ends of the lamp 1 a. At one contact pin 6b of the holder 3b of one end the voltage feed comes directly from the means for voltage feed 10. To the holder 3a at the other end of the lamp 1 a, and through it, at the contact pin 6a the voltage is connected from the means for feed 10 via ballast 4. Inside LED tube 6 the voltage is connected to the circuit board or substrate 6d from contact pins 6a and 6b via conductors 62 and 61 .

There are two problems with the presented wiring. The bigger one is the danger of electric shock. If the LED tube 6 has been mounted only into one of the holders 3a or 3b, the contact pin 6a or 6b at the other end of the LED tube 6 can be live. Another problem is that the LED tube 6 has to be installed in just a specific position. This is because in both holders 3a and 3b, only one contact belonging to the holder has been electrically connected with the means for voltage feed 10. Therefore, contact pins 6a and 6b have to be mounted with exactly that contact of the holder 3a and 3b which has been connected to the voltage feed circuit.

In Fig. 1 c has been illustrated another way of connecting a LED tube 6a to the lamp 1 b. The external voltage feed arrangement corresponds for the most part to the feed arrangement of a conventional fluorescent tube. However, the starter 5 required by a fluorescent tube has been removed, whereby the starter circuit is disconnected.

In this solution, the LED tube 6a includes a circuit board or a substrate 6d to which several separate LED light sources 6c have been connected. The circuit board or substrate 6d can further include voltage converter circuits and control circuits required by the LEDs 6c. Voltage feed has been arranged via holders 3a and 3b at both ends of the lamp 1 b. At the contact pins 6b1 and 6b2, which have been connected inside the LED tube 6a and are to be mounted to the holder 3b of one end of the lampl b, the voltage feed comes directly from the means for voltage feed 10. To the holder 3a at the other end of the lamp 1 b, and via it at the contact pins 6a1 and 6a2, which have been connected inside the LED tube 6a, the voltage is fed from the means for voltage feed 10 via ballast 4. Inside the LED tube 6a the voltage is coupled to the circuit board or substrate 6d from the contact pins 6a2 and 6b2 via conductors 62 and 61 .

There is still a danger of electric shock in the illustrated connection because the voltage is led with conductors 62 and 61 from one end of the LED tube 6a to the other. If the LED tube 6a has been mounted to only one of the holders 3a or 3b of the lamp 1 b, the contact pin 6a1 /6a2 or 6b1 /6b2 at the other end of the LED tube 6a can be live and give an electric shock. In this solution, the LED tube 6a can, however, be mounted into any position. This is because the contact pins have been connected at both ends of the LED tube.

In Fig. 1 d has been illustrated the LED tube connection disclosed in publication AU 2009101044. In the solution of the publication the danger of electric shock when mounting a LED tube has been avoided. In the lamp 1 c according to the publication, starter 5 has been removed and the conductor 14 leading to the starter 5 has been disconnected and the disconnected conductor 14 has been connected to the conductor 15 coming from the means for feed 10. Moreover, the conductor starting from the ballast 4 has been rewired so that it leads to the same holder 3b as the conductor 15 coming directly from the means for voltage feed 10. According to the publication, the ballast 4 can also be bypassed with a conductor 1 1 a. In both cases the holder 3a at one end of the LED lamp 1 c is fully disconnected from the external voltage feed. Because the voltage is connected with conductors 61 and 62 via contact pins 6b1 and 6b2 from the voltage feed point to the LEDs 6c within the LED tube 6b, the contact pins 6a1 and 6a2 at the other end of the LED tube 6b need not be connected to anything within the LED tube 6b. Such a structure provides for that the LED tube 6b can be mounted only to one of the holders 3a and 3b and even then there is no danger of electric shock at the other end of the LED tube 6b. There are still two problems with the solution disclosed in publication AU 2009101044. LED tube 1 b needs to always be installed so that the contact pins 6b1 and 6b2 of the LED tube 1 b, to which the circuit board or substrate 6d comprising LEDs 6c has been connected, is mounted to the holder 3b of the lamp 1 c, which holder 3b has been coupled with the means for voltage feed 10. If the LED tube 6b is mounted the other way around, the LEDs 6c do not burn, because there is no voltage feed in the holder 3a. Further, only a LED tube according to the publication can be used in lamp 1 c after the alterations and it is no longer possible to use for example a conventional fluorescent tube.

Summary of the invention The object of the invention is to disclose a new LED tube and a LED lamp utilizing it, where there is no danger of electric shock during installation of the tube. Moreover, a LED lamp according to the invention does not require that the LED tube be mounted to the holders of the light frame in a certain position. Further, an average user can still utilize also conventional fluorescent tubes in addition to the LED tube in a LED lamp according to the invention.

The objects of the invention are achieved with a LED lamp fitted into the frame of a conventional fluorescent lamp in which the starter required by a conventional fluorescent tube is replaced by a plug-in connection element. Further, within the LED tube proper the voltage is fed only from one end of the LED tube and the contact pins of the LED tube at its other end are electrically connected.

An advantage of the LED lamp according to the invention is that there is no danger of electric shock while mounting a LED tube or a fluorescent tube. A further advantage of the invention is that when replacing the starter with a dummy connector while using a LED tube, live parts potentially exposed when the starter required by a conventional fluorescent tube is removed are automatically covered.

A still further advantage of the invention is that when a conventional fluorescent tube is replaced by a LED tube or vice versa, the wiring of the lamp need not be changed.

Yet another advantage of the invention is that the LED tube according to the invention can be installed into the holders of the light frame whichever way.

Yet another advantage of the invention is that, if so desired, the LED tube can be replaced by a conventional fluorescent tube by installing in addition to it only the starter required by the fluorescent tube.

Still another advantage of the invention is that the dummy connector advantageously includes also a fuse which will protect the user if a LED tube is replaced by a fluorescent tube and it is forgot to replace the dummy connector with a starter.

A LED tube according to the invention is characterised in that the two contact pins at the second end of the LED tube have been shorted to arrange voltage feed to the first end of the LED tube via the existing wiring of the fluorescent lamp.

A LED lamp according to the invention is characterised by that in the LED lamp: - wiring is uniform with that of a fluorescent lamp;

- a connection element has been arranged to be connected to the starter connection means, with which element an external circuit has been arranged to be connected from the second holder of the LED lamp to the first holder of the LED lamp;

- in order to arrange voltage feed to the first end of the LED tube, the two contact pins at the second end of the LED tube have been shorted; and - voltage feed to the LEDs of the LED tube has been arranged to be done only from the first end of the LED tube.

Some advantageous embodiments of the invention have been described in the dependent claims. The basic idea of the invention is the following: in a LED lamp or the installation arrangement of a LED tube according to the invention is advantageously utilized the already existing wiring for a fluorescent lamp. In a LED lamp according to the invention, only the starter required by a fluorescent lamp is replaced by a connection element according to the invention. The connection element comprises advantageously a connector, fuse, or conductor. Voltage feed to the LED tube according to the invention is implemented only from one end of the LED tube. The contact pins at the other end of the LED tube have been shorted within a LED tube according to the invention. When a connection element according to the invention is in place, the LED tube can be mounted to the holders of the original fluorescent lamp without a danger of electric shock because there is no voltage in the contact pins at the uninstalled end of the LED tube, and there are not any unprotected live parts in the light frame.

A LED lamp according to the invention provides for that the user can in the same light frame safely use both conventional fluorescent tubes and LED tubes only by changing into place the starter or the dummy connector.

In the following the invention will be described in detail. Reference will be made to the accompanying drawings in which

Fig. 1 a shows by way of example a connecting system of a conventional fluorescent lamp; Fig. 1 b shows by way of example a connecting system of a conventional LED tube;

Fig. 1 c shows by way of example a second connecting system of a LED tube;

Fig. 1 d shows by way of example a third connecting system of a LED tube;

Fig. 2 shows by way of example a LED lamp according to the invention and a LED tube used therein; and Fig. 3 shows by way of example a second installation position of a LED tube according to the invention in a LED lamp.

The embodiments of the invention illustrated in the following description are exemplary only and a person skilled in the art can implement the basic idea of the invention also in some other way than the one described in the description. Although reference can be made to an embodiment or embodiments in several places in the description, this does not mean that the reference would be aimed at only one described embodiment or that the described feature would be usable only in one described embodiment. Individual features of two or more embodiments can be combined and thus new embodiments of the invention can be provided.

Figures 1 a-1 d have been presented in connection of the description of prior art.

Fig. 2 shows an example of a LED tube 21 according to the invention and a lamp 20 into which the LED tube 21 has been mounted.

A LED tube 21 according to the invention comprises at least partly translucent illuminating tube 23 and at its both ends blanking adapters made out of a dielectric substance which the contact pins of the LED tube 21 penetrate. A LED tube 21 according to the invention corresponds in setting dimensions to a standardized fluorescent tube in regards that it can be connected to the frame of a conventional fluorescent lamp. Thus, it can be installed mechanically and electrically into a light frame designed for a standard fluorescent tube (only holders 3a and 3b of the light frame are shown in Fig 2). A LED tube 21 according to the invention comprises advantageously a circuit board or substrate 21 d onto which the LEDs 21 c of the LED tube have been attached. There can also be voltage shaping circuits and circuits used for control of the LEDs on the circuit board or substrate 21 d Voltage can be connected to the LED tube 21 only through the contact pins 21 b1 and 21 b2 at its first end. From these, the voltage used in the LED tube 21 can be led onto a circuit board or substrate 21 d with conductors 212 and 21 1 . The contact pins 21 a1 and 21 a2 at the second end of the LED tube 21 have been electrically shorted 213 within the LED tube 21 . This shorting enables connection and utilizing of an external circuit via contact pins 21 a1 and 21 a2 of the LED tube. The contact pins at different ends of the LED tube 21 are not electrically connected by connections within the LED tube 21 . Fig. 2 illustrates also a LED lamp 20 in which a LED tube 21 according to the invention is utilized. A LED lamp 20 according to the invention comprises means for voltage feed 10, connection wires 1 1 , 12, 13, 14, and 15, ballast 4, connection element 22, LED tube 21 , contact pins 21 a1 , 21 a2, 21 b1 , and 21 b2 belonging to the LED tube, and holders 3a and 3b of the LED tube in the framework of the LED lamp 20 (the rest of the mechanic light frame is not shown in Fig 2). The LED tube 21 is connected mechanically and electrically from its both ends with contact pins 21 a1 , 21 a2, 21 b1 , and 21 b2 to the holders 3a and 3b belonging to the light frame, in which holders there are contacts for fastening the contacts pins 21 a1 , 21 a2, 21 b1 , and 21 b2 of the LED tube 21 .

The voltage is connected to the LED lamp 20 according to the invention from the means for voltage feed 10. The first voltage feed point of the LED tube 21 is in the contact pin 21 b2 of the first holder 3b of the LED lamp 20 and the voltage is led therein by means of a conductor 15 directly from the means for voltage feed 10.

The second voltage feed point of the LED tube 21 is in the contact pin 21 b1 of the first holder 3b of the LED lamp 20. Therein the voltage is led from the means for voltage feed 10, first by a conductor 1 1 to the ballast 4 and from there by conductor 12 to the second holder 3a of the LED lamp 20. Since the contact pins 21 a1 and 21 a2 at the second end of the LED tube 21 have been electrically shorted 213 within the LED tube 21 , the voltage is connected from the contact pin 21 a1 in the holder 3a via conductor 13 to the connection element 22. The connection element 22 can be for example a connector, fuse, conductor, or some combination thereof. From the connection element 22 the voltage is connected via conductor 14 to the contact pin 21 b1 in the first holder 3b of the lamp 20 if the connection element 22 is electrically conductive. Thus the voltage required by the LED tube 21 according to the invention can be fed via contact pins 21 b1 and 21 b2 connected to the first holder 3b.

The electric wiring of the lamp utilized in the installation of the LED tube depicted in the example of Fig. 2 corresponds to the electric wiring of a conventional fluorescent tube apart from that the connection element 22 replaces the starter required by a conventional fluorescent tube. In this embodiment, there is no need to make any other changes to the wiring of the LED lamp 20 according to the invention compared to the wiring of a conventional fluorescent lamp, when the fluorescent tube is replaced by a LED tube 21 according to the invention. In one advantageous embodiment of the invention also the ballast 4 required by a fluorescent lamp has been removed or bypassed and the voltage of the LED tube 21 is led from the means for voltage feed 10 directly via conductors 1 1 and 12 to the second holder 3b of the LED lamp. In this embodiment the LED tube cannot be replaced by a fluorescent tube.

In a case illustrated in Fig. 3, LED tube 21 has been installed into another connected position of removable part possible in lamp 20. In the example of Fig. 3 the contact pins 21 b1 and 21 b2 at the first end of the LED tube 21 have been mounted to the second holder 3a at the second end of the LED lamp 20. The electrical interconnection 213 between the contact pins 21 a1 and 21 a2 at the second end of the LED tube 21 is then located in the first holder 3b at the first end of the LED lamp 20. It can be seen from Fig. 3 that the voltage feed required by the LED tube 21 is realized also in the case of Fig. 3. The LED tube 21 according to the invention can thus be installed in either of the two possible installation options so that power is supplied irrespective of the installation option.

Also in this embodiment there is no need to make changes in the wiring of the LED lamp 20 according to the invention compared to the wiring of a conventional fluorescent lamp when the fluorescent tube is replaced by a LED tube 21 according to the invention. The foregoing describes some advantageous embodiments of a LED lamp according to the invention and a LED tube utilized therein. The invention is not limited to the exact depicted embodiments but the inventive idea can be applied in numerous ways within the scope set by the claims.