U.S. patent application number 10/893370 was filed with the patent office on 2006-01-19 for electric hand tool.
This patent application is currently assigned to MOBILETRON ELECTRONICS CO., LTD.. Invention is credited to Harry Chang, Cheng I. Teng.
Application Number | 20060011367 10/893370 |
Document ID | / |
Family ID | 35598234 |
Filed Date | 2006-01-19 |
United States Patent
Application |
20060011367 |
Kind Code |
A1 |
Teng; Cheng I. ; et
al. |
January 19, 2006 |
Electric hand tool
Abstract
An electric hand tool includes a housing, which houses a driving
mechanism and a chuck for driving a bit, a battery pack for
providing electricity to the driving mechanism, and a switch unit
installed in the housing. The switch unit has a switch, an
operating member for switching on/off the switch to control supply
of electricity from the battery pack to the driving mechanism, and
a switching lever extended out of a through hole in the rear
portion of the housing and forming a switching portion for
operation by the thumb of the hand holding the housing to drive the
switching lever to change the direction of electric current and to
further reverse the direction of rotation of the driving
mechanism.
Inventors: |
Teng; Cheng I.; (Taichung
County, TW) ; Chang; Harry; (Taichung City,
TW) |
Correspondence
Address: |
BACON & THOMAS, PLLC
625 SLATERS LANE
FOURTH FLOOR
ALEXANDRIA
VA
22314
US
|
Assignee: |
MOBILETRON ELECTRONICS CO.,
LTD.
TAICHUNG HSIEN
TW
|
Family ID: |
35598234 |
Appl. No.: |
10/893370 |
Filed: |
July 19, 2004 |
Current U.S.
Class: |
173/217 |
Current CPC
Class: |
B25F 5/00 20130101; B25B
21/00 20130101 |
Class at
Publication: |
173/217 |
International
Class: |
E21B 19/18 20060101
E21B019/18 |
Claims
1. An electric hand tool comprising: a housing having a front
portion provided with an opening, and a rear portion; a driving
mechanism installed in said housing; a chuck coupled to said
driving mechanism and extending out of the opening of said housing
to hold a bit for turning by said driving mechanism; a battery pack
for providing electricity to said driving mechanism; and a switch
unit installed in said housing, said switch unit having a switch,
an operating member connected to said switch for switching on/off
said switch to control supply of electricity from said battery pack
to said driving mechanism, and a switching lever for driving said
switch to change the direction of electric current provided by said
battery pack, said switching lever having a switching portion at
one end thereof; wherein said rear portion of said housing has a
through hole through which said switching portion of said switching
lever extends for operation by a user; and wherein said switching
lever has a first end pivoted to said switch and a second end
forming said switching portion.
2. The electric hand tool as claimed in claim 1, wherein said
switching lever comprises a first link having a first end pivoted
to said switch and a second end, and a second link having a first
end pivoted to the second end of said first link and a second end
forming said switching portion.
3. (canceled)
4. The electric hand tool as claimed in claim 1, wherein said
switching portion has an indication zone for indicating the
direction of rotation of the chuck.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an electric hand tool and
more particularly, to such an electric hand tool, which is
practical for use in a narrow place for enabling the user to
conveniently change the direction of rotation of the electric hand
tool.
[0003] 2. Description of the Related Art
[0004] A commercially available electric hand tool essentially
comprises a housing, a driving mechanism installed in the housing,
a chuck coupled to the driving mechanism and partially extended out
of the housing to hold a bit, a battery pack for providing
electricity to the driving mechanism, and a switch unit. The switch
unit comprises an ON/OFF switching button for operation by the user
to determine whether the electricity provided by the battery pack
is supplied to the driving mechanism, and a direction switching
member for operation by the user to determine the direction of
electric current provided by the battery pack and to further
determine the rotation direction of the driving mechanism that
drivers the chuck.
[0005] The conventional direction switching member has a switching
rod having an end coupled to a switch that controls the direction
of the supplied electric current, and the other end connected to an
operation member. The operation member has two ends extended
respectively out of two opposite lateral sidewalls of the housing
of the electric hand tool for operation by the user such that the
switch is controlled to determine the direction of electric current
provided by the battery pack by the operation member through the
switching rod.
[0006] This design of electric hand tool is functional; however, it
is not convenient for use in a narrow place. When wishing to
reverse the direction of rotation of the electric hand tool during
working of the electric hand tool in a narrow place that has no
room for the user's hand to operate the operation member, the user
shall have to stop the operation, and remove the electric hand tool
out of the narrow place, and then to adjust the operation member to
change the direction of electric current provided by the battery
pack, and then to insert the electric hand tool into the narrow
place again. This inconvenient operation situation lowers the
working efficiency. In addition, the conventional electric hand
tool has no indication to tell the direction of rotation thereof.
The user must press the ON/OFF switching button to power the
electric hand tool so as to learn the direction of rotation thereof
whenever the electric hand tool is not operated. This is
inconvenient.
SUMMARY OF THE INVENTION
[0007] It is the primary objective of the present invention to
provide an electric hand tool, which is practical for use in a
narrow place for enabling the user to conveniently change the
direction of rotation of the electric hand tool.
[0008] To achieve this objective of the present invention, the
electric hand tool comprises a housing, a driving mechanism
installed in the housing, a chuck, a battery pack for providing
electricity to the driving mechanism, and a switch unit installed
in the housing. The housing has a front portion provided with an
opening, and a rear portion. The chuck is coupled to the driving
mechanism and extends out of the opening of the housing to hold a
bit for turning by the driving mechanism. The switch unit has a
switch, an operating member connected to the switch for switching
on/off the switch to control supply of electricity from the battery
pack to the driving mechanism, and a switching lever for driving
the switch to change the direction of electric current provided by
the battery pack. The switching lever has a switching portion at
one end thereof. The rear portion of the housing has a through hole
through which the switching portion of the switching lever extends
for operation by a user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a side view of an electric hand tool according to
a first preferred embodiment of the present invention.
[0010] FIG. 2 is a partial sectional view of the electric hand tool
according to the first preferred embodiment of the present
invention.
[0011] FIG. 3 is a rear view of the electric hand tool according to
the first preferred embodiment of the present invention.
[0012] FIG. 4 is a partial sectional view of an electric hand tool
according to a second preferred embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Referring to FIGS. 1-3, an electric hand tool 10 in
accordance with the first preferred embodiment of the present
invention is shown comprised of a housing 20, a driving mechanism
30, a chuck 40, a battery pack 50, and a switch unit 60.
[0014] The housing 20 comprises a first part 21 and a second part
22. The first part 21 has a first end 23 and a second end 24. The
first end 23 has a front portion 25 and an opening 26 in the front
portion 25. The second part 22 extends from the second end 24 of
the first part 21 at an angle. The second part 22 has a rear
portion 27 opposite to the front portion 25 of the first end 23 of
the first part 21, and a through hole 28 in the rear portion 27.
The second part 22 further has an opening 29.
[0015] The driving mechanism 30 is installed in the first part 21
of the housing 20, comprising a motor 31.
[0016] The chuck 40 is installed in the first part 21 of the
housing 20 and coupled to the driving mechanism 30, having a chuck
shell 41 extending out of the opening 26 of the housing 20 to hold
a bit (not shown) for working.
[0017] The battery pack 50 is detachably fastened to the rear end
of the second part 22 of the housing 20 to provide electricity to
the motor 31 of the driving mechanism 30.
[0018] The switch unit 60 is installed in the second part 22 of the
housing 20, comprising an operating rod 61, a switching lever 62,
and a switch 63. The operating rod 61 has one end connected to the
switch 63 and the other end connected to a button 64 that extends
out of the housing 20 through the opening 29. The user can press
the button 64 to control the switch 63. The switching lever 62 is
comprised of a first link 65 and a second link 66. The first link
65 is pivoted to the top of the switch 63, and forwardly backwardly
turnable relative to switch 63 to control the switch 63 to change
the direction of electric current provided by the battery pack 50.
The second link 66 has one end pivoted to the free end 67 of the
first link 65 and the other end extended out of the through hole 28
in the rear portion 27 of the housing 20 and forming a switching
portion 68 for pushing by the user. The user can push the switching
portion 68 to force the second link 66 to pivot the first link 65,
thereby causing the switch 63 to change the direction of electric
current provided by the battery pack 50. In addition, the switching
portion 68 has an indication zone 69 on which letters of "R" (not
shown) and "L" are marked for indicating the right-handed and
left-handed rotation direction. As shown in FIG. 3, when the
switching portion is pushed to left end of the through hole 28, the
indication letter of "L" can be seen by the user such that the user
can learns that the hand tool is under a left-handed rotation
status.
[0019] When using the electric hand tool 10, the user can hold the
second part 22 of the housing 20 with the hand and press the button
64 with the forefinger to drive the operating rod 61 and to further
switch on the switch 65, thereby causing the battery pack 50 to
provide electricity to the motor 31. Further, the user can move the
switching portion 68 of the switching lever 62 with the thumb,
causing the second link 66 to bias the first link 65 and to further
drive the switch 63 to change the direction of electric current
provided by the battery pack 50, and therefore the direction of
rotation of the bit of the electric hand tool 10 is revered.
[0020] As indicated above, the switching portion 68 for controlling
the direction of rotation of the bit of the electric hand tool 10
is set in the rear portion 27 of the housing 20. Therefore, the
user can conveniently drive the switching portion 68 with the thumb
to change the direction of electric current when using the electric
hand tool 10 in a narrow work place. Further, the indication zone
69 of the switching portion 68 provides directly the direction of
rotation of the hand tool to the user, thereby enhancing the
working convenience.
[0021] The switching lever is not limited to the aforesaid design.
FIG. 4 shows a second preferred embodiment of the present
invention. According to this embodiment, the electric hand tool 70
is comprised of a housing 71, a driving mechanism 72, a battery
pack 73, and a switch unit 74. The housing 71, the driving
mechanism 72, and the battery pack 73 are similar to the
corresponding members of the aforesaid first embodiment. The switch
unit 74 comprises a switching lever 75 and a switch 76. The
switching lever 75 has one end pivoted to the switch 76, and the
other end extended out of a through hole 78 of the housing 71 and
forming a switching portion 77. The user can directly drive the
switching portion 77 to switch the switch 76, causing the switch 76
to change the direction of electric current provided by the battery
pack 50.
* * * * *