Patent Publication Number: US-6341881-B1

Title: Single-conductor positioning device on a bulb holder

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is related to a single-conductor positioning device on each or either lateral side of a bulb holder, and especially to such a device capable of firmly positioning a single conductor at a central position on each or either lateral side of the bulb holder. 
     2. Description of the Prior Art 
     Conventional decorative lamps are mostly in the form of strings each having multiple lamp bulbs connected to a conductor; modern decorative lamps of such kind are arranged in a plane in the form of a net, thereby conventional lamp strings were developed to have the plane decorative function. 
     Early decorative lamps in the form of nets, such as that in the U.S. Pat. No. 5,662,409 owned by the applicant of the present application, must have multiple lamp bulbs positioned at different locations on the entire network, hence locking members are required to secure every lamp bulb on the net formed by conductor for the lamp bulbs. 
     Using the locking members on decorative lamps in the form of nets to position multiple lamp bulbs not only is inconvenient in construction, but also is uneconomic. In view of this, modern decorative lamps in the form of nets have for each bulb holder a conductor-positioning device integrally formed therewith to save the abovementioned locking members additionally provided. Such an integrally formed conductor-positioning device was disclosed in U.S. Pat. Nos. 5,839,819, 5,908,238 and 6,116,951. 
     In the U.S. Pat. No. 5,839,819 as an example, a connecting base is integrally formed on a lateral side of the bulb holder; the connecting base has an outward groove, thereby, the conductor for the lamp bulbs can be placed in the connecting base through the groove. Although the patent has the advantage of omitting a locking member additionally provided and fast positioning on the conductor, the front face of the outward groove faces to the lateral side of the bulb holder, thereby, when the decorative lamps in the form of a net is pulled sideways, the outwardly facing direction of the groove for clamping therein the conductor is coincident with the direction of stretching of the net light. In this mode, the bulb holder and its lamp bulb are much subjected to getting off their positions when the conductors are exerted with pulling force. Thereby, the whole net light looses its static or dynamic flashing or illuminating patterns previously set. Such a connecting base with the outward groove on the lateral side totally opened is subjected to pulling sideways and thus lack of the ability of sure positioning the conductor. 
     The U.S. Pat. No. 6,116,951 also provided a conductor clamping device for such a net light; wherein, the bulb holders each is also integrally formed with a connecting base merely the same as that of the aforesaid connecting base. The connecting base is provided on a lateral side thereof with a protruding rib which is connected to the connecting base by means of an engagement block; the engagement block is provided with a concave groove matching with the protruding rib. Thereby, the engagement block can synchronically position two conductors passing through the corresponding lamp bulbs and its bulb holders when it is connected to the connecting base. 
     However, such a net light generally has singular conductors passed through lamp bulbs and their corresponding bulb holders in the process of manufacturing. Positioning of a singular conductor must be very firm to prevent getting off during pulling sideways, and must be accurately positioned at the centers of the lateral sides of the bulb holders. In this mode, fixed assembling of the entire net light can only be assured, and the lamp bulbs can surely be located at the intercrossing points of net lines, such locating can influence the pattern of flashing of the lamp bulbs. The above stated U.S. Pat. No. 5,839,819 is unable to get firm positioning of the conductor; while the U.S. Pat. No. 6,116,951 is evidently hard to suit accurate positioning of the conductor. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a single-conductor positioning device on each or either lateral side of a bulb holder; the device is capable of firmly positioning a single conductor at a central position on each or either lateral side of the bulb holder. 
     To obtain the above stated object, the present invention is provided with a receiving seat integrally formed on each or either lateral side of the bulb holder and comprised of two hook-like sidewalls opposite to each other. A plug can be fitted in an inner slot and a central slit both formed in the receiving seat. In this preferred embodiment, the plug can form together with the inner slot of the receiving seat a conductor clamping-slot; and can further be provided with vertical grooves for connecting with the hooks of the sidewalls of the receiving seat. Thus the phenomenon that the outward groove of a connecting base is subjected to pulling sideways to make a conductor get off its position by a pulling force can be effectively prevented. 
     In this preferred embodiment, the plug has a base slightly enlarged and used as a limit portion against pushing. 
     And in another preferred embodiment, the conductor clamping-slot formed by a recess of the plug and the receiving seat is formed to be a conical hole, and has a raised strip. 
     In another preferred embodiment, the plug can be formed independently a conductor sleeve on the external surface of the receiving seat. 
     The present invention will be apparent in its novelty and features after reading the detailed description of the preferred embodiment thereof in reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an analytic perspective view showing elements of the present invention, wherein, the receiving seat and the plug are provided on only one lateral side of the bulb holder; 
     FIG. 2 is a perspective view showing assembling and positioning of a single conductor of FIG. 1; 
     FIG. 3 is a sectional view of the bulb holder shown in FIG. 1; 
     FIG. 4 is a bottom view of the bulb holder shown in FIG. 1; 
     FIG. 5 is a sectional view of the plug shown in FIG. 1; 
     FIG. 6 is an analytic perspective view showing elements of the present invention similar to FIG. 1, wherein, receiving seats and plugs are provided on both lateral sides of the bulb holder; 
     FIG. 7 is a perspective view showing assembling and positioning of the elements of FIG. 6; 
     FIG. 8 is a perspective view showing another embodiment of the present invention; 
     FIG. 9 is a schematic perspective view showing using of the present invention in a net light. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, the present invention is provided with a receiving seat  20  integrally formed on one lateral side of a bulb holder  10 . In a preferred embodiment, the receiving seat  20  is comprised of two hook-like sidewalls opposite to each other and each including a pair of integral but mutually perpendicular wall portions  21 ,  22  and  23 ,  24 . An inner slot  25  is formed within the wall portions  21 ,  22  and  23 ,  24 ; and a central slit  26  with a width slightly smaller than the diameter of a conductor is formed in the receiving seat  20 . The wall portions  22 ,  24  on both sides of the central slit  26  are further folded to form respectively hooks  27 ,  28 . A recessed surface  291  is formed centrally on an inner wall  29  of the inner slot  25 , in this preferred embodiment, the recessed surface  291  is a conical surface which is smaller at the upper portion than the lower portion thereof (referring to FIGS. 3,  4 ), and has a raised strip  292  on the surface thereof. 
     A plug  30  has a section in the shape matching with the shapes of the inner slot  25  and the central slit  26  of the bulb holder  10 . In this preferred embodiment, the plug  30  has a base  31 , and has two vertical grooves  32 ,  33  respectively in opposition to the aforementioned hooks  27 ,  28 , and a clamping recess  34  is provided in opposition to the aforementioned recessed surface  291 . The clamping recess  34  is preferably a part of a conical surface which is larger at the upper portion than the lower portion thereof, and has a raised strip  35  on the surface thereof (referring to FIG.  5 ). 
     And as shown in FIGS. 1 and 2, according to the above stated embodiment, a conductor  90  can be pressed into the inner slot  25  through the central slit  26  of the bulb holder  10 , then the plug  30  is inserted in from the bottom of the receiving seat  20 . During the process of assembling, the recessed surface  291  and the clamping recess  34  of the plug  30  together form a clamping hole for the conductor  90 . By cooperation of tight pressing of the plug  30  and the raised strips  292 ,  35  respectively on the recessed surface  291  and the clamping recess  34 , it is assured that the conductor  90  can be tightly positioned. At the same time, when the plug  30  is pressed for assembling, the clamping recess  34  is slipped over the aforementioned hooks  27 ,  28  of the receiving seat  20 . Such an assembly can render the wall portions  21 ,  22  and  23 ,  24  of the receiving seat  20  to be clamped and restrained; the central slit  26  will not be pulled to stretch to make dropping of the conductor  90  therein no matter it is pulled in any direction. The base  31  of the plug  30  will be used as a positioning member during press insertion; when the plug  30  is completely inserted, the base  31  will abut against the bottom face of the receiving seat  20  to stop further pushing of the plug  30 . 
     In the embodiment shown in FIG. 6, two receiving seats  201 ,  202  are simultaneously provided on two opposite lateral sides of a bulb holder  100 , and two plugs  301 ,  302  are used, such that the bulb holder  100  can have two singular conductors  901 ,  902 . 
     FIG. 8 shows another embodiment of the present invention, wherein, a bulb holder  101  is provided with a receiving seat  203  on one side thereof. However, the inner slot  205  thereof can have a slightly reduced width. With the inner slot  205  and a central slit  26  of the receiving seat  203 , a plug  303  in this embodiment can similarly be provided with a base  304  having in the receiving seat  203  vertical grooves  305 ,  306 , but a sleeve  307  is formed extending outwardly for clamping a conductor. When the plug  303  is combined with the receiving seat  203 , the conductor can be positioned at a central position on the external surface of the receiving seat  203 . 
     FIG. 9 shows that the embodiment of FIG. 6 of the present invention is applied in a net light. It can be seen, singular conductors  90  of every bulb holder  10  is firmly positioned at a central line on both sides of the bulb holder  10 . In this way, not only that the conductors  90  are not easy to drop in pulling, the lamp bulb  109  on each bulb holder  10  is also accurately positioned at an intercrossing point of net lines, thereby, the entire net light can have more tidy and reliable pattern expressing and flashing under the control of an electric circuit (not shown). 
     The embodiment cited above is only for illustrating a preferred embodiment of the present invention. It will be apparent to those skilled in this art that various modifications or changes can be made to the elements of the present invention without departing from the spirit and scope of this invention. Accordingly, all such modifications and changes also fall within the scope of the appended claims and are intended to form part of this invention.