Telescopic illuminating tool

A telescopic illuminating tool includes a handle with an accommodating chamber for receiving a battery unit, and first and second electric contacts spaced apart each other. A plurality of telescopic metal concentric tubes is connected to a head of the handle at one end and, is provided with a bulb seat at an opposite end. The bulb seat has a contact area in electrical contact with a ring contact of an electric bulb, and a third electric contact in electrical contact with the concentric tubes. A stretchable electrically conductive member, such as a tension spring with an electrically insulative sheath thereon, is secured in the concentric tubes for connection with a tip contact of the bulb and a first electric contact of the handle which, in turn, is adapted to be in electrical contact with one electrode of the battery unit. A second electric contact of the handle is in electrical contact with the concentric tubes and the other electrode of the battery unit. The stretchable electrically conductive member can be stretched or retracted when the concentric tubes are extended or shortened, thereby adjusting desirably the length of the illuminating tool.

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.

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.