Background of the Invention
1. Field of the Invention
This invention relates to a telescopic illuminating tool, more particularly to a telescopic illuminating tool with telescopic tubes and a stretchable electrically conductive wire disposed in the telescopic tubes for electrical connection with a battery unit and an electric bulb.
2. Description of the Related Art
Referring to FIG. 1, a conventional illuminating tool is shown to include a conductive barrel housing 1 for receiving a battery unit 2, a press button 3 which is disposed outwardly of a rear end of the housing 1, and a flexible core 4 which has an end connected to a front end of the housing 1, and the other end provided with an electric bulb 5 and a tool member 6. The electric bulb 5 is lighted by the battery unit 2, and the flexible core 4 can be adjusted at any desired angle. However, the flexible core 4 can not be adjusted in length, thereby resulting in inconvenience during use.
Referring to FIG. 2, another conventional illuminating tool is shown to include a plurality of metal tubes 11 which are fitted telescopically and slidably with one another, a switch member 12, a battery receiving tube 14 for receiving battery cells 13, and a plurality of spiral conducting wires 17, each received in the respective metal tube 11. Since the conducting wires 17 are made of enameled wires which are difficult to be stretched, the extension range of the illuminating tool is limited.
Summary of the Invention
The object of the present invention is to provide a telescopic illuminating tool which has a stretchable electrically conducting member made of a single conducting wire and received in telescopically concentric tubes so as to be stretched or retracted when the tubes are extended or shortened, thereby adjusting the illuminating tool in length when desired.
According to this invention, a telescopic illuminating tool includes a hollow handle which has an accommodating chamber for receiving a battery unit, and first and second electric contacts which are insulatively spaced apart from each other and which are adapted to be connected electrically and respectively with the two electrodes of the battery unit. A plurality of electrically conductive concentric tubes are fitted telescopically and slidably one within another, and form an opened second head end, an opposite opened second tail end, and a through hole extending therethrough. The opened second tail end engages a first head end of the handle, and is electrically connected to the second electric contact. A bulb seat is connected to the opened second head end, and defines a contact area and a third electric contact which is spaced apart from the contact area. The third electric contact is in electric connection with the opened second head end. A stretchable electrically conductive member is disposed securely in the through hole, and is insulated from the electrically conductive concentric tubes. The stretchable electrically conductive member has a front end which extends into the contact area of and which is secured relative to the bulb seat to form a fourth electric contact, and an opposite rear end which is connected to the first electric contact. As such, the stretchable electrically conductive member will be stretched or retracted when the electrically conductive concentric tubes are extended or shortened. An electric bulb is disposed in the bulb seat to be lighted via an electrical contact between the third electric contact and the fourth electric contact. A tool member is disposed to be spaced from and forwardly of the electric bulb.
Brief Description of the Drawings
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments of the invention, with reference to the accompanying drawings, in which:
FIG. 1 is an assembled, partly sectional view of a conventional illuminating tool;
FIG. 2 is an exploded view of another conventional illuminating tool;
FIG. 3 is a sectional view of a preferred embodiment of a telescopic illuminating tool according to this invention;
FIG. 4 is a partial cross-sectional view of the telescopic illuminating tool shown in FIG. 3, taken along lines 4--4 thereof;
FIG. 5 is a partial cross-sectional view of the telescopic illuminating tool shown in FIG. 3, taken along lines 5--5 thereof;
FIG. 6 is an assembled view of the preferred embodiment in an extended state;
FIG. 7 is an enlarged view of a portion of the telescopic illuminating tool in use; and
FIG. 8 illustrates a modified telescopic illuminating tool of this invention.
Detailed Description of the Preferred Embodiments
Referring to FIG. 3, the preferred embodiment of a telescopic illuminating tool according to the present invention is shown to comprise an elongate handle 20, an electrically insulative connecting member 40, a plurality of electrically conductive concentric tubes 50, an electrically conductive bulb seat 60, a stretchable electrically conductive member 80, an electric bulb 70, a tool member, and a switch member 100.
The handle 20 is made of a plastic material, and has a first head end, a first tail end opposite to the first head end in an axial direction and with an inner threaded wall 22, an accommodating chamber which is interposed between the first head and tail ends for receiving a battery 30, a first electric contact 26 which is disposed on the first head end and at a location in the axial direction, and a second electric contact 90 (described hereinafter in detail) which is disposed to be insulatively spaced apart from the first electric contact 26 in a radial direction. The first and second electric contacts 26, 90 are adapted to be connected electrically and respectively with two electrodes of the battery 30. The handle 20 has a splined outer wall 21 to facilitate gripping thereof. With reference to FIG. 4, two side grooves 23 and an upper groove 24 are formed in an inner wall of the handle 20 parallel to the axial direction. The first head end of the handle 20 further has an axial mounting groove 231 which is formed to flank one of the side grooves 23, and a screw hole 25 which is formed transverse to the axial direction.
The connecting member 40 has a front portion 41 which tapers gradually and forwardly, and a rear portion 42 which is connected to the first head end of the handle 20. The rear portion 42 has two side engaging plugs 44 and an upper plug 45 (see FIG. 4) which are formed axially and which are fitted in the corresponding grooves 23, 24 of the handle 20. The rear portion 42 further has a screw hole 43 which is formed transverse to the axial direction such that a screw fastener 46 engages threadedly the screw holes 25, 43. In addition, the connecting member 40 has a passage which extends therethrough in the axial direction for passage of the first electric contact 26.
The concentric tubes 50 are fitted telescopically and slidably one within another, and form an opened second head end 51", an opened second tail end 51' opposite to the opened second head end 51" in the axial direction, and a through hole 54 which extends through the opened second head and tail ends 51", 51' and which is communicated with the passage of the connecting member 40. The opened second tail end 51' engages securely the connecting member 40 via a hollow electrically conductive fastener 52. An electrically insulative block 53 is disposed between the fastener 52 and the accommodating chamber of the handle 20 to electrically insulate the fastener 52 and the battery 30, and has a hole for passage of the first electric contact 26 into the through hole 54 of the concentric tubes 50.
The bulb seat 60 is connected to the opened second head end 51", and has an inner threaded wall 62 to define a contact area around the axial direction to be communicated with the through hole 54, and a connecting portion 61 which is disposed to be spaced apart from the inner threaded wall 62 to be connected to the opened second head end 51" and to confine a third electric contact in electrical connection with the opened second head end 51".
The stretchable electrically conductive member 80 is an electrically conductive tension spring wire which is sheathed with an electrically insulative sheath, and is disposed securely in the through hole 54. The electrically conductive member 80 has a front end which extends into the contact area of the bulb seat 60 and which is secured relative to the bulb seat 60 to form a fourth electric contact 81, and a rear end 82 opposite to the front end in the axial direction and which is connected to the first electric contact 26. When the electrically conductive concentric tubes 50 are extended or shortened, the stretchable electrically conductive member 80 can be stretched or retracted in the axial direction.
The electric bulb 70 is disposed in the bulb seat 60, and has an outer threaded wall which is connected to the inner threaded wall 62 of the bulb seat 60 with a ring contact to be in electrical contact with the contact area, and a tip contact to be to be in electrical contact with the fourth electric contact 81 of the electrically conductive member 80.
The second electric contact 90 of the handle 20 includes a conducting plate 91, a conducting rod 92, and a conducting spring 93. The conducting plate 91 is disposed between the fastener 52 and the insulative block 53, and has an extension 911. The conducting rod 92 is disposed in the axial mounting groove 231, and has a third head end which is connected electrically to the extension 911 of the electrically conductive plate 91, and an opposite third tail end which is disposed in the first tail end of the handle 20 and which has a ring portion 921 disposed on the inner threaded wall 22. The conducting spring 93 is disposed in the first tail end of the handle 20, and has a fourth head end which is adapted to be connected electrically to the other one of the electrodes of the battery unit 30, and an opposite fourth tail end which has a connecting portion 932, and a contact portion 931 that extends diametrically and outwardly from the connecting portion 932 so as to be spaced apart from the ring portion 921 of the conducting rod 92 in a direction parallel to the axial direction.
The switch member 100 is connected to the first tail end of the handle 20, and has an outer threaded wall 110 for engaging threadedly the inner threaded wall 22 so as to be rotatable about the axial direction relative to the handle 20. With reference to FIG. 7, the switch member 100 has a concavity 120 for receiving the conducting spring 93, and two axial slots 121 for receiving the contact portion 931 of the conducting spring 93. The connecting portion 932 of the conducting spring 93 abuts against a bottom of the concavity 120. As such, the switch member 100 can be rotated to move the contact portion 931 toward the ring portion 921 of the conducting rod 92 against a biasing force of the conducting spring 93 to make an electrical contact between the contact portion 931 and the ring portion 921.
With reference to FIG. 5, the tool member includes an adapter 200 which is made of a light-transmittable material, and which has an end connected threadedly to the bulb seat 60 and formed with a receiving recess 210 for receiving the electric bulb 70. The adapter 200 has an opposite threaded end 230 with a hexagonal hole 240 formed therein in the axial direction, and two axial slits 260 which are communicated with the hexagonal hole 240. A tool unit 400 has a hexagonal coupling end 410 which is inserted detachably into the hexagonal hole 240 of the adapter 200, and a magnet 420 opposite to the hexagonal coupling end 410 in the axial direction. A collet chuck mechanism 300 has a screw hole 310 with a diameter slightly smaller than that of the opposite threaded end 230 of the adapter 200, and sleeved threadedly on the opposite threaded end 230 to couple the tool unit 400 tightly onto the adapter 200.
In use, when the concentric tubes 50 are extended to stretch the electrically conductive member 80 in the axial direction, as shown in FIG. 6, the illuminating tool can be used to reach a narrow place to pick up an object. In addition, with reference to FIG. 3, when the switch member 100 is rotated inward of the handle 20 to establish electrical contact between the contact portion 931 and the ring portion 921, the tip contact of the bulb 70 is in electrical connection with one of the electrodes of the battery 30 via the electrically conductive member 80 and the first electric contact 26, while the ring contact of the bulb 70 is in electrical connection with the other one of the electrodes of the battery 30 via the contact area of the bulb seat 60, the concentric tubes 50, the fastener 52, the conducting plate 91, the conducting rod 92, and the conducting spring 93, thereby lighting the bulb 70. On the other hand, when the switch member 100 is rotated outwardly relative to the handle 20, the electric contact between the contact portion 931 and the ring portion 921 is broken to deactivate the bulb 70.
Note that the stretchable electrically conductive member 80 is made of a piano wire with a smaller diameter compared with an enameled wire and a larger extendable length, and is applied to connect the bulb 70 and the battery 30 without being sectioned, thereby facilitating assembly and fabrication of the conductive member 80.
Referring to FIG. 8, a modified preferred embodiment of this invention is shown to be similar in construction to the previous embodiment, except that a mirror 420' is attached to the coupling end 410' of the tool unit 400' for reflecting purposes.
While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretations and equivalent arrangements.