Abstract:
A light emitting diode (LED) lamp and socket system is disclosed. The lamp comprises a first pair of side connecting pins adapted to provide electrical input to at least one LED, the first pair of side connecting pins positioned at an angle from one another such that the angle between the first pair of side connecting pins is defined from the horizontal cross-sectional center of the lamp and the first pair of side connecting pins protrudes outwards from the lamp. The socket is adapted for receiving a LED lamp partially therein, it comprises a base portion adapted to secure at least one pair of side connecting pins of the LED lamp and a top portion adapted for receiving at least one pair of electrical wires, such that when the base portion and top portion are connected, each of the at least one pair of side connecting pins electrically contacts an electrical wire and thereby provides electrical input to the LED lamp.

Description:
FIELD OF THE INVENTION 
     The present invention relates to light emitting diodes (LED) lamps. The invention is particularly suited, but not limited to LED lamps having electrical power consumption of at least one wattage. 
     BACKGROUND TO THE INVENTION 
     The following discussion of the background of the invention is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge in any jurisdiction as at the priority date of the application. 
     Current LED lamps generally have to be adapted to conform to traditional lamp fitting standards such as MR-16, E27 and/or GU-10 because these fitting standards are often not suitably adapted for the electrical polarity required for LED. One way to adapt a LED lamp to a traditional fitting standard is to integrate the LED lamp system design by incorporating its own fixture design, lens system, driver circuitry and transformer circuitry etc. However, when any of the mentioned components breaks down, the whole lamp invariably has to be replaced due to its integrated design. This results in unnecessary wastage and increase the overall cost of replacing the LED lamps. 
     Due to the comparatively lower heat tolerance compared to traditional lamps, additional heat-sinks and/or other heat dissipation devices are often required to be separately attached to the LED lamps during fitting to dissipate heat and preserve the life-span of the LEDs. It has been noted by the applicant that the electrical conducting portion of the traditional fitting standard is typically positioned at an end of the LED lamp opposite the lamp head. Such positioning meant that the heat dissipation devices have to be attached to other portions of the LED lamps instead. However, when the heat dissipation devices are attached to other portions of the LED lamps, the heat dissipation device is likely to be obstructed by other components required during fitting. This may limit the heat dissipating capability of the heat dissipation devices due to the restricted air flow caused by the above mentioned obstruction. In addition, attaching the heat dissipation devices to these other portions may result in irregularity in the overall shape of the lamp, hence requiring the corresponding socket and fitting mechanisms to be adapted to suit such irregularity. 
     Another problem which may arise is the fact that a user typically is not able to distinguish between the electrical inputs required for different LED lamps easily. Often, they have to rely and read the electrical specification manual in order to ensure that the right type of LED lamp is matched with the right electrical input. Carelessness on the part of the user may compromise safety, causing hurt to the user and damage to the LED lamp. 
     It is thus an object of the invention to overcome, or at least ameliorate in part, one or more of the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     Throughout this document, unless otherwise indicated to the contrary, the phrase “comprising”, “consisting of”, and the like, are to be construed as inclusive and not exhaustive. 
     In accordance with a first aspect of the present invention there is a light emitting diode (LED) lamp, the lamp comprising a first pair of side connecting pins adapted to provide electrical input to at least one LED, the first pair of side connecting pins positioned at an angle from one another such that the angle between the first pair of side connecting pins is defined from the horizontal cross-sectional center of the lamp and the first pair of side connecting pins protrudes outwards from the lamp. 
     Preferably, when the electrical input is a constant current input, the angle between the first pair of side connecting pins is 150 degrees. 
     Preferably, when the electrical input is a constant voltage input, the angle between the first pair of side connecting pins is 165 degrees. 
     Preferably, when the electrical input is an alternating current input, the angle between the first pair of side connecting pins is 180 degrees. 
     Preferably, when the at least one LED source is a bi-color LED, the lamp further comprises a second pair of side connecting pins. 
     Preferably, when the at least one LED source is a RGB LED, the lamp further comprises a second and third pair of side connecting pins. 
     Preferably, the side connecting pins are arranged such that each side connecting pin has a different polarity with respect to its adjacent side connecting pin. 
     Preferably, the lamp further comprises a printed circuit board (PCB), the PCB configured to connect each side connecting pin to the LED. Preferably, the PCB regulates the electrical input to control the brightness and electrical power supplied to the LED. 
     Preferably, a heat sink is attached to the lamp such that the overall shape of the lamp is cylindrical. Preferably, the heat sink has the same diameter as the lamp. 
     Preferably, the lamp includes a reflector and lamp head cover. 
     Preferably, each side connecting pin is positioned at the angle of at least thirty degrees from any other side connecting pin. 
     In accordance with a second aspect of the invention there is a socket adapted for receiving a LED lamp partially therein, the socket comprising a base portion, the base portion adapted to secure at least one pair of side connecting pins of the LED lamp at a first angle as defined from the horizontal cross-sectional center of the base portion; and a top portion, the top portion adapted for receiving at least one pair of electrical wires; such that when the base portion and top portion are connected, each of the at least one pair of side connecting pins contacts an electrical wire and thereby provides electrical input to the LED lamp. 
     Preferably, the at least one pair of electrical wires are arranged such that when connected, each electrical wire supplies electricity of a different polarity with respect to its adjacent electrical wires. 
     Preferably, when the electrical input is a constant current input, the first angle is 150 degrees. 
     Preferably, when the electrical input is a constant voltage input, the first angle is 165 degrees. 
     Preferably, when the electrical input is an alternating current input, the first angle is 180 degrees. 
     In accordance with a third aspect of the invention there is a LED lamp system, the system comprising a socket as defined in the second aspect of the invention; and a LED lamp as defined in the first aspect of the invention, where the LED lamp is partially received in the socket such that electrical input provided by the at least one pair of electrical wires is supplied to the LED lamp by way of the at least one pair of side connecting pins. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following invention will be described with reference to the accompanying drawings of which: 
         FIG. 1  is the isometric view of the parts of a LED lamp according to the embodiment of the present invention. 
         FIG. 2  is the top view of the LED lamp shown in  FIG. 1  according to the embodiment of the present invention. 
         FIG. 3   a  is the side view of the parts of a LED lamp according to the embodiment of the present invention. 
         FIG. 3   b  is the isometric view of the assembled LED lamp according to the embodiment of the present invention. 
         FIG. 4   a  is the isometric view of a socket adapted for fitting the embodiment of the invention,  FIG. 4   b  is the isometric view of an alternative socket to  FIG. 4   a .  FIG. 4   c  is the close-up side profile view of an opening for receiving a side connecting pin of the LED lamp. 
         FIG. 5   a  and  FIG. 5   b  are the isometric views of the LED lamp attached to the socket in  FIG. 4   a  according to the embodiment of the present invention. 
         FIGS. 6   a  to  6   c  are the top views of the LED lamp shown in  FIG. 1  according to the two side connecting pin configuration of the present invention. 
         FIGS. 7   a  and  7   b  are the top views of the LED lamp shown in  FIG. 1  according to an alternative four side connecting pin configuration of the present invention adapted for holding bi-color LEDs. 
         FIGS. 8   a  and  8   b  are the top views of the LED lamp shown in  FIG. 1  according to an alternative six side connecting pin configuration of the present invention adapted for holding RGB LEDs. 
     
    
    
     Other arrangements of the invention are possible and, consequently, the accompanying drawings are not to be understood as superseding the generality of the preceding description of the invention. 
     DETAILED DESCRIPTION OF THE INVENTION 
     In accordance with an embodiment of the invention there is a LED lamp  10 . The embodiment comprises a lamp head assembly  12 , two side connecting pin modules  14 , a LED assembly  16  and a heat sink  18  as shown in  FIG. 1 . 
     The lamp head assembly  12  comprises a lamp head holder  20  and a reflector  22 . The lamp head holder  20  is a circular cap comprising a first ring  24  and a second ring  26 . The first ring  24  and second ring  26  are integrally moulded to form the lamp head holder  20 . The first ring  24  and second ring  26  are co-centric and share the same outer diameter d outer  (see  FIG. 3   a ). The first ring  24  and second ring  26  differs in their inner diameter such that the inner diameter d inner,first  of the first ring  24  is smaller than the inner diameter d inner,second  of the second ring  26  as shown in  FIG. 3   a.    
     The reflector  22  is a circular conical frustum. A base portion  28  of the reflector  22  is sized and shaped to fit within the lamp head holder  20 . The base portion  28  of the reflector  22  has the largest diameter relative to the whole reflector  22 . A portion of the reflector  22  with the smallest diameter is sized and shaped to receive a surface mounted LED  52 . The diameter of the base portion  28  is slightly smaller or equal to the inner diameter d inner,second  of the second ring  26 , but is larger than the inner diameter d inner,first  of the first ring  24 . 
     Each side connecting pin module  14  comprises a curved rectangular base  30 , a side connecting pin  32  and an electrical conducting plate  34 . The curved rectangular base  30  has two extension flaps  36  integrally moulded with it. Each extension flap  36  has a smaller thickness than the curved rectangular base  30 . The two extension flap  36  extends outwards from two opposite ends of the curved rectangular base  30  respectively. The two opposite ends are perpendicular to a lower end  38  of the curved rectangular base  30 . The two opposite ends are substantially parallel to each other. Side connecting pin  32  is positioned proximate the lower end  38  of the curved rectangular base  30 . A first portion  40  of the side connecting pin  32  extends substantially perpendicular from an outer convex surface  33  of the curved rectangular base  30 . A second portion  42  of the side connecting pin  32  extends substantially perpendicular from an inner concave surface  35  of the curved rectangular base  30 . The first portion  40  of the side connecting pin  32  is longer than that of the second portion  42 . Side connecting pin  32  is made of an electrical conducting material such as copper. 
     The electrical conducting plate  34  extends contiguously from the second portion  42  of the side connecting pin  32 . Each electrical conducting plate  34  is oriented, when assembled, such that its largest surface contacts a printed circuit board (PCB)  50  via solder pads  44 . 
     The LED assembly  16  comprises PCB  50  and a surface mounted LED  52  mounted thereon. The surface mounted LED  52  is typically a high power surface mounted LED commonly available in the market. The PCB  50  is configured to connect the side connecting pins  32  and surface mounted LED  52 . The PCB may be further configured to regulate electrical input to the surface mounted LED  52 . This regulation allows for some control to be exercised over the brightness of the surface mounted LED  52 . As the means by which the PCB  50  regulates electrical input to the surface mounted LED  52  would be well known to the person skilled in the art it will not be further described herein. 
     The heat sink  18  comprises a plurality of fins  60  and two slots  62 . Fins  60  are shaped and sized to increase the surface area of the heat sink  18  for heat dissipation. Each of the two slots  62  are sized and adapted to receive a side connecting pin module  14 . The overall shape of the heat sink  18  in this embodiment is cylindrical. 
     The embodiment is next described in the context of manufacturing the LED lamp  10 . 
     The PCB  50  and the surface mounted LED  52  are first fitted onto the heat sink  18  using two securing screws (not shown). Two holes  70  are sized and shaped to receive the two securing screws. Thermal contact between the PCB  50  and the heat sink  18  is ensured by applying a heat sink compound as known to a person skilled in the art. The heat sink compound provides a thermal contact for the heat sink  18  to dissipate heat away from the PCB  50 . 
     The side connecting pin modules  14  are fitted within slots  62  of the heat sink  18 . Each side connecting pin modules  14 , when so fitted is positioned such that:
         (i) the two extension flaps  36  lie snugly on the inner curved surface of the heat sink  18 ;   (ii) the outer convex surface  33  of the side connecting pin module  14  sits flush with the outer curved surface of the heat sink  18 ; and   (iii) An end  46  opposite the lower end  38  of side connecting pin modules  14  flushes with the non-fin end of heat sink  18 .       

     The electrical conducting plates  34  of the side connecting pin module  14  are then soldered onto the PCB  50 . 
     The smallest diameter end of the reflector  22  is positioned on the surface mounted LED  52 . The lamp head holder  20  is then positioned on top of the reflector  22  such that the base portion  28  contacts the first ring  24 . The isometric view of the fully assembled LED lamp  10  is shown in  FIG. 3   b.    
     The various components of the LED lamp  10  are then sealed together with methods known to a person skilled in the art. 
     When viewed from the top as seen in  FIG. 2 , when the side connecting pins  32  are angled to form an upright ‘V’, the first side connecting pin  32   a  is of negative polarity and the second side connecting pin  32   b  is of positive polarity. 
     Upon assembly, the LED lamp  10  is attached onto a socket  80  as shown in  FIG. 4 . The parts of the socket  80  are described as follows. 
     The socket  80  comprises a socket top plate  82  and a socket base  84 . Two wire holders  86  are positioned on the socket top  82 . Each wire holder  86  further comprises a spring loaded connector  90  and a square block  92 . The square block  92  has a hole  94  adapted to receive wires  88 . When the spring loaded connector  90  is pushed downwards, the hole  94  on the square block  92  is unblocked to allow an exposed (un-insulated) end of wire  88  to be slotted into the hole  94 . Upon releasing the spring loaded connector  90 , hole  94  is blocked; the spring loaded connector  90  exerts a force against the exposed end of wire  88 , securing the exposed end of wire  88  such that the exposed end of wire  88  contacts the square block  92  and is prevented from moving out of the square block  92 . 
     The socket base  84  is adapted to receive the two side connecting pins  32 . The socket base  84  comprises an inner circular portion  96  and a co-centric outer circular portion  98 . The inner circular portion  96  has two openings  100 . The two openings  100  are adapted to receive the two side connecting pins  32 . An angle α between the two openings  100 , as taken from the centre of the inner circular portion  96 , will be described in more detail below. The centre of the inner circular portion  96  corresponds to the LED lamp  10 . 
     Extended from one end  102  of each opening  100  is a flap  104 . A gap  106  between the flap  104  and another end  108  is sized to receive a side connecting pin  32 . 
     Two connector springs  110  provides electrical connection between the two wires  88  and the side connecting pins  32 . For each connector spring  110 , a first end  112  contacts the exposed end of the wire  88 . A second end  114  of the connector spring  110  is adapted to contact the side connecting pin  32 . The first end  112  of the connector spring  110  is connected to its corresponding square block  92  via rivets (not shown). The first end  112  is shorter than the second end  114 . 
     When a side connecting pin  32  is pushed into the gap  106  between the flap  104  and end  108 , the side connecting pin  32  contacts the connector spring  110 . As the side connecting pin  32  is pushed into the gap, the connector spring  110  exert a force pushing the side connecting pin  32  in a direction opposite the direction of entry. Upon rotating the LED lamp  10  in a direction away from end  108 , the side connecting pin  32  is moved away from end  108  along the edge of the flap  104  towards end  102  until it rests on a connecting portion  107 . At this position, the LED lamp  10  is attached to the socket  80 . It is to be appreciated that throughout the movement of the side connecting pin  32 , the connector spring  110  contacts the side connecting pin  32  and continues to maintain contact with the side connecting pin  32  when it rests on the connecting portion  107 . 
     Depending on the type of electrical input, the angle α between the two side connecting pins  32  is adjusted accordingly. The type of electrical input and the corresponding angle between the two side connecting pins modules  14  are presented in  FIG. 6   a  to  FIG. 6   c  and are described as follows:
     (a) When the electrical input is a constant DC current input, the angle α between the two side connecting pin modules  14 , i.e. between side connecting pin  1  and side connecting pin  2  is 150 degrees as shown in  FIG. 6   a      (b) When the electrical input is a constant DC voltage input, the angle α between the two side connecting pin modules  14 , i.e. between side connecting pin  1  and side connecting pin  2  is 165 degrees as shown in  FIG. 6   b.      (c) When the electrical input is an alternating current AC input, the angle α between the two side connecting pin modules  14 , i.e. between side connecting pin  1  and side connecting pin  2  is 180 degrees as shown in  FIG. 6   c.      

     The present embodiment may be further modified to suit different types of LEDs  52 . 
     For example, four side connecting pin modules  14  are used for providing electrical input to a bi-color LED as presented in  FIG. 7   a  and  FIG. 7   b . The socket  80  is modified to match the additional side connecting pins  32  by having four openings  100  and four wire holders  86 . The heat sink  18  is modified to have four slots  62 . The respective angles α, β, γ, r between each of the four side connecting pin  32  are then defined as follows:
     (a) When the electrical input is a constant DC current input, the angle α between side connecting pin  1  and side connecting pin  2  is 150 degrees; the angle β between side connecting pin  1  and side connecting pin  3 /side connecting pin  4  is 90 degrees; and the angle γ between side connecting pin  3  and side connecting pin  4  is 180 degrees as shown in  FIG. 7   a.      (b) When the electrical input is a constant DC voltage input, the angle α between side connecting pin  1  and side connecting pin  2  is 165 degrees; the angle β between side connecting pin  1  and side connecting pin  3 /side connecting pin  4  is 90 degrees; and the angle γ between side connecting pin  3  and side connecting pin  4  is 180 degrees as shown in  FIG. 7   b.      

     As another example, six side connecting pin modules  14  are used for providing electrical input to a RGB LED as presented in  FIG. 8   a  and  FIG. 8   b . The socket  80  is modified to match the additional side connecting pins by having six openings  100  and six wire holders  86 . The heat sink  18  is modified to have six slots  62 . The respective angles α, β, γ, η, p, q between each side connecting pin  32  are defined as follows:
     (a) When the electrical input is a constant DC current input, the angle α between side connecting pin  1  and side connecting pin  2  is 150 degrees, the angle β between side connecting pin  1  and side connecting pin  3 /side connecting pin  4  is 90 degrees; the angle γ between side connecting pin  3  and side connecting pin  4  is 180 degrees; the angle η between side connecting pin  1 /side connecting pin  3  and side connecting pin  5  is 45 degrees; the angle p between side connecting pin  4  and side connecting  6  is 45 degrees; and the angle q between side connecting pin  5  and side connecting pin  6  is 180 degrees as shown in  FIG. 8   a.      (b) When the electrical input is a constant DC voltage input, the angle α between side connecting pin  1  and side connecting pin  2  is 165 degrees; the angle β between side connecting pin  1  and side connecting pin  3 /side connecting pin  4  is 90 degrees; the angle γ between side connecting pin  3  and side connecting pin  4  is 180 degrees; the angle η between side connecting pin  1 /side connecting pin  3  and side connecting pin  5  is 45 degrees; the angle p between side connecting pin  4  and side connecting pin  6  is 45 degrees; and the angle q between side connecting pin  5  and side connecting pin  6  is 180 degrees as shown in  FIG. 8   b.      

     Unless stated to the contrary, all defined angles (α, β, γ, η, p, q) refer to the angle as taken from the centre of the LED lamp  10 , as per angle α. 
     The above examples ensures that the right type of socket is fitted with the right number of side connecting pins, with the additional differentiating factor of different angles between the side connecting pins corresponding to different type of electrical input. Hence, while satisfying the electrical input requirements, the arrangement of the side connecting pins also eliminates errors on the part of a user fitting the LED lamp  10 , thus enhances safety. In addition, the positioning of the side connecting pins  32  extending from the side of the LED lamp  10  near the lamp head assembly  12  enables the heat sink  18  to be directly attached to the LED assembly  16  without obstructing the socket  80  during fitting. 
     The similar outer diameter d outer  of the heat sink  18  and the LED lamp  10  achieves a regular cylindrical design when they are integrated, thus promoting easy fitting using regular tools. 
     In addition, the current LED lamp  10  is kept independent from the other components such as the transformer circuitry. Should the LED lamp  10  spoils, the LED lamp  10  may be isolated from the other components and replaced without the need to replace other components, thereby reducing costs. 
     An alternative socket  80 , where like numerals reference like parts, is illustrated in  FIG. 4   b . The alternative socket  80  provides a different direction of entry for the LED lamp  10  during fitting. The alternative socket  80  has its two wire holders  86  positioned on a socket top  82  but at the other end in respect to the socket  80  described earlier. Each wire holder  86  is adapted to receive wires  88  similar to that described earlier. 
     Similar to the fitting process described earlier, when a side connecting pin  32  is pushed between the flap  104  and end  108 , the side connecting pin  32  contacts the connector spring  110  (not shown). Upon rotating the LED lamp  10  in a direction away from end  108 , the side connecting pin  32  is moved away from end  108  along the edge of the flap  104  towards end  102  until it rests on a connecting portion  107 . At this position, the LED lamp  10  is attached to the socket  80 . 
     It should be appreciated by the person skilled in the art that the invention is not limited to the examples described. In particular, the following additions and/or modifications can be made without departing from the scope of the invention:
         The first ring  24  may be covered with a circular transparent covering as part of the water proofing feature for the LED lamp  10 .   The PCB  50  may be further adapted to hold multiple surface mounted LEDs  52  as would be known to a person skilled in the art. The lamp head holder  20  may be replaceable by that known to a person skilled in the art. Typically, they may be a sealed, threaded or clip type.   The LED  52  need not be surface mounted. As an alternative, the LED  52  may be attached to a LED holder, and the LED holder shaped and sized to receive a LED  52 , or a plurality of LEDs  52 .   The lamp head assembly  12  may be replaced by focusing lens, diffuser or bulb head diffuser etc. for different lighting requirements and applications as known to a person skilled in the art.   The side connecting pin module  14  may be integrally moulded with the lamp head assembly  12 . The lamp head assembly  12  is then attached to heat sink  18  via any commonly known securing mechanism e.g. clipping, or groove-flange mechanism as known to a person skilled in the art. In this case slots  62  on the heat sink are no longer required.       

     It should be further appreciated by the person skilled in the art that features and modifications discussed above, not being alternatives or substitutes, can be combined to form yet other embodiments that fall within the scope of the invention described.