Background of Invention
1. Field of Invention
[0001] The present invention relates to a pneumatic tool and, more particularly, to a pneumatic
tool equipped with a direction switch operable with a single hand.
2. Related Prior Art
[0002] Disclosed in Taiwanese Patent Publication
No. 387316 is a pneumatic tool 1 equipped with a direction switch operable with a single hand.
The pneumatic tool 1 includes a handle 11 on which an upper control member 2 and a
lower control member 3 are installed. The upper control member 2 is operable to cause
the pneumatic to rotate or stop. The lower control member 3 is operable to cause the
pneumatic tool to rotate in a direction or an opposite direction. A user operates
the pneumatic tool with a single hand. The user holds the handle 11 and the lower
control member 2 with the thumb, the middle finger, the ring finger and the little
finger. The user presses the lower control member 2 with the middle finger, the ring
finger and the little finger in order to cause the pneumatic tool to rotate. The user
operates the upper control member 3 with the index finger.
[0003] However, there are problems with this conventional pneumatic tool. Firstly, the user
soon have fatigue in the hand, pressing the lower control member 2 with the middle
finger, the ring finger and the little finger while keeping the index finger off the
upper control member 3. The user might get hurt in the hand if using this pneumatic
tool for long. Moreover, the user cannot hold the pneumatic tool steady with the middle
finger, the ring finger and the little finger. Furthermore, the user may unintentionally
press the upper control member 3 with the index finger and change the direction of
the rotation of the pneumatic tool, and this could dangerous.
[0004] Disclosed in
Taiwan Patent Publication M275925 is a direction switch of a pneumatic tool. A space 16 is defined in a front side
of a handle 15 of a piston-shaped body 10 of the pneumatic tool. The direction switch
includes a block 20 for controlling air currents. The block 20 defines upper and lower
intakes 21, upper and lower outlets 22 and two apertures 23. All of the intakes 21,
the outlets 22 and the apertures 23 are horizontal. The block 20 defines four channels
24 are vertical for communicating the apertures 23 with the intakes 21 and the outlets
22. Long rods 25 are positioned in the intakes 21. Short rods 25' are positioned in
the outlets 22. A user operates the pneumatic tool with a single hand. The user holds
the handle 15 with the thumb, the ring finger and the little finger. The user presses
an upper portion of a trigger 30 with the index finger in order to cause the pneumatic
tool to rotate in a first direction, and alternatively presses a lower portion of
the trigger 30 with the middle finger in order to cause the pneumatic tool to rotate
in a second direction opposite to the first direction.
[0005] However, there are problems with this conventional direction switch. To cause the
pneumatic tool to rotate in the first direction, the user keeps on pressing the upper
portion of the trigger 30 with the index finger while keeping the middle finger off
the lower portion of the trigger 30. To cause the pneumatic tool to rotate in the
second direction, the user keeps on pressing the lower portion of the trigger 30 with
the middle finger while keeping the index finger off the upper portion of the trigger
30. The user soon has fatigue in the hand. The user might get hurt in the hand if
using this pneumatic tool for long. Moreover, the user cannot hold the pneumatic tool
steady with the middle finger, the ring finger and the little finger. In addition,
the user may unintentionally change the direction of the rotation of the pneumatic
tool, and this could dangerous. Furthermore, the elements are numerous, and the direction
switch is complicated. The assembly, the maintenance and the repair of the direction
switch are difficult. Moreover, in operation, only one pair of the intake 21 and the
outlet 22 is used while the other pair of the intake 21 and the outlet 22 is idle,
and this is a waste.
[0006] The present invention is therefore intended to obviate or at least alleviate the
problems encountered in prior art.
Summary of Invention
[0007] According to the present invention, a pneumatic tool is operable with a single hand.
The pneumatic tool includes a shell defining a first chamber and a second chamber.
The second chamber includes intake and outlet apertures in communication with the
first chamber. A cylinder is in the first chamber. A controller is movable in the
second chamber between a first position and a second position. The controller includes
a first groove and a second groove. In the first position, the first groove communicates
with the intake aperture for directing pressurized air to drive the cylinder in a
first direction. In the second position, the second groove communicates with the intake
aperture for directing pressurized air to drive the cylinder in a second direction.
A cover seals the first chamber and the second chamber. The cover defines an opening
through which the controller extends from the second chamber so that the controller
can be moved.
[0008] The primary advantage of the pneumatic tool according to the present invention is
the simple structure for the use of the simple controller including only the first
and second grooves.
[0009] Other advantages and features of the present invention will become apparent from
the following description referring to the attached drawings.
Brief Description of Drawings
[0010] The present invention will be described through detailed description of the preferred
embodiment referring to the drawings.
Fig. 1 is a perspective view of a pneumatic tool according to the preferred embodiment
of the present invention.
Fig. 2 is an exploded view of the pneumatic tool shown in Fig. 1.
Fig. 3 is a cross-sectional view of the pneumatic tool shown in Fig. 1.
Fig. 4 is a cross-sectional view of the pneumatic tool along a line 4-4 in Fig. 3.
Fig. 5 is a cross-sectional view of the pneumatic tool in another position than shown
in Fig. 1.
Fig. 6 is a cross-sectional view of the pneumatic tool along a line 6-6 in Fig. 5.
Fig. 7 is a perspective view of a controller used in the pneumatic tool shown in Fig.
2.
Detailed Description of Preferred Embodiment
[0011] Referring to Fig. 1, shown is a pneumatic tool according to the preferred embodiment
of the present invention.
[0012] Referring to Figs. 2 through 4, the pneumatic tool includes a shell 10 and a handle
13 projecting from the shell 10. The shell 10 defines a first chamber 11, a second
chamber 15, a first channel 16 and a second channel 17. The first chamber 11 receives
a cylinder 12 for driving a striker 18. The second chamber 15 receives a controller
30.
[0013] The handle 13 defines an intake 131 and an outlet 132. The intake 131 receives a
valve 133 movable by means of a trigger 14 installed on the handle 13.
[0014] The second chamber 15 is in communication with the first channel 16 through an aperture
151 on a side. The second chamber 15 is in communication with the second channel 17
through an aperture 152 on another side. The second chamber 15 is in communication
with the first chamber 11 through an aperture 153 near an end. Moreover, the second
chamber 15 is in communication with the first chamber 11 through an aperture 154 near
an opposite end. The second chamber 15 is in communication with the intake 131 through
an aperture 155.
[0015] The controller 30 can be switched between a first position and a second position.
In the first position, the controller 30 causes the cylinder 12 to rotate in a first
direction. In the second position, the controller 30 causes the cylinder to rotate
in a second position opposite to the first direction.
[0016] The controller 30 defines a first groove 31 on a side and a second groove 32 on an
opposite side. The first groove 31 is separated from the second groove 32. The first
groove 31 and the second groove 32 may be rectilinear, helical or S-shaped. The first
groove 31 can be brought into communication with the first channel 16 through the
aperture 151. The second groove 32 can be brought into communication with the second
channel 17 through the aperture 152.
[0017] The first groove 31 includes a downward intake end 311 and an upward outlet end 312.
The intake end 311 is from the outlet end 312 by a distance 301. The second groove
32 includes a downward intake end 321 and an upward outlet end 322. The intake end
311 is from the outlet end 322 by a distance 301. Along the length of the controller
30, the intake end 321 and the outlet end 322 of the second groove 32 are positioned
between the intake end 311 and the upward outlet end 312 of the first groove 31.
[0018] In the preferred embodiment, the distance 301 is smaller than the diameter of the
aperture 155 so that the controller 30 can be switched between two positions, i.e.,
the first and second positions. In another embodiment, the distance 301 may be larger
than the diameter of the aperture 155 so that the controller 30 can be switched between
three positions, i.e., a neutral position, a first working and a second working position.
The relation between the distance 301 and the diameter of the aperture 155 is similar
and will not be described in detail.
[0019] Attached to the shell 10 is a cover 20 for sealing the first chamber 11 and the channels
16 and 17. The cover 20 defines an opening 21 in communication with the second chamber
15. On an external side of the cover 20 are two pivots 22 between which the opening
21 is. Although not shown for being conventional, the cover 20 defines two channels
in communication with the channels 16 and 17, respectively. Thus, the pressurized
air can between the cylinder 12 and the channels 16 and 17 through the channels on
the internal side of the cover 20.
[0020] The controller 30 includes two ears 33 at an end. A T-shaped link 34 is connected
to the ears 33. When the controller 30 is inserted in the second chamber 15 through
the opening 21, the T-shaped link 34 is positioned outside. A lever 35 defines a T-shaped
groove 351 and two recesses 352 on a side. The T-shaped groove 351 receives the T-shaped
link 34 so that the lever 35 is connected to the T-shaped link 34. The recesses 352
receive the pivots 22 so that the lever 35 is installed on the pivots 22 like a seesaw.
The lever 35 includes a first section on a side of the pivots 22 and a second section
on another side of the pivots 22.
[0021] Referring to Figs. 3 and 4, a user operates the pneumatic tool with a single hand.
The user pushes down the first section of the lever 35 with the thumb, and then moves
the thumb from the lever 35, leaving the first section of the lever 35 down. The controller
30 is in the first position. To turn on the pneumatic tool, the user operates the
trigger 14 with the index finger. Now, the user holds the handle 13 and the trigger
14 steady with all of the thumb, the index finger, the middle finger, the ring finger
and the little finger.
[0022] The pressurized air goes from the intake 131 into the intake end 311 of the first
groove 31 through the aperture 155. The pressurized air leaves the outlet end 312
of the first groove 31 for the first channel 16 through the aperture 151. The pressurized
air goes from the first channel 16 into an upper portion of the first chamber 11 through
one of the channels of the cover 20. The pressurized air drives the cylinder 12 in
the first direction. Then, the pressurized air leaves the upper portion of the first
chamber 11 for the second channel 17 through the other channel of the cover 20. The
pressurized air leaves the second channel 17 for the intake end 321 of the second
groove 32 through the aperture 152. The pressurized air leaves the outlet end 322
of the second groove 32 for a lower portion of the first chamber 11. The pressurized
air leaves the lower portion of the first chamber 11 for the outlet 132 through the
aperture 154. Finally, the pressurized air leaves the pneumatic tool from the outlet
132.
[0023] Referring to Figs. 5 and 6, the pushes down the second section of the lever 35 with
the thumb, and then moves the thumb from the lever 35, leaving the second section
of the lever 35 down. The controller 30 is in the second position. To turn on the
pneumatic tool, the user operates the trigger 14 with the index finger.
[0024] The pressurized air goes from the intake 131 into the intake end 321 of the second
groove 32 through the aperture 155. The pressurized air leaves the outlet end 322
of the second groove 32 for the second channel 17 through the aperture 152. The pressurized
air leaves the second channel 17 for the upper portion of the first chamber 11 through
one of the channels of the cover 20. The pressurized air drives the cylinder 12 in
the second direction. Then, the pressurized air leaves the upper portion of the first
chamber 11 for the first channel 16 through the other channel of the cover 20. The
pressurized air leaves the first channel 16 for the intake end 311 of the first groove
31 through the aperture 151. The pressurized air leaves the outlet end 312 of the
first groove 31 for the lower portion of the first chamber 11 through the aperture
153. The pressurized air leaves the lower portion of the first chamber 11 for the
outlet 132 through the aperture 154. Finally, the pressurized air leaves the pneumatic
tool from the outlet 132.
[0025] The pneumatic tool according to the present invention exhibits several advantages.
Firstly, the user holds the handle 13 and the trigger 14 steady with all of the thumb,
the index finger, the middle finger, the ring finger and the little finger.
[0026] Secondly, to switch the cylinder 12 from one direction to another, the user operates
the lever 35 with the thumb only. Having finished the switching, the user moves the
thumb from the lever 35 to the handle 13. Thus, the user does not operate the lever
35 by mistake.
[0027] Thirdly, the structure of the pneumatic tool is simple for the use of the simple
controller 30 including only the first groove 31 and the second groove 32.
[0028] The present invention has been described through the description of the preferred
embodiment. Those skilled in the art can derive variations from the preferred embodiment
without departing from the scope of the present invention. Therefore, the preferred
embodiment shall not limit the scope of the present invention defined in the claims.
1. A pneumatic tool operable with a single hand, the pneumatic tool comprising:
a shell (10) defining a first chamber (11) and a second chamber (15), the second chamber
(15) comprising an intake aperture (153) in communication with a portion of the first
chamber (11) and an outlet aperture (154) in communication with another portion of
the first chamber (11);
a cylinder (12) positioned in the first chamber (11);
a controller (30) movable in the second chamber (15) between a first position and
a second position, the controller (30) comprises a first groove (31) and a second
groove (32) so that in the first position, the first groove (31) communicates with
the intake aperture (153) in order to direct pressurized air to drive the cylinder
(12) in a first direction, and that in the second position, the second groove (32)
communicates with the intake aperture (153) in order to direct pressurized air to
drive the cylinder (12) in a second direction; and
a cover (20) for sealing the first chamber (11) and the second chamber (15), the cover
(20) defining an opening (21) through which the controller (30) extends from the second
chamber (15) so that the controller (30) can be moved.
2. The pneumatic tool according to claim 1 comprising a handle (13) projecting from the
shell (10) and a trigger (14) on the handle (13) so that the trigger (14) is operable
by the index finger.
3. The pneumatic tool according to claim 1 comprising a lever (35) connected to the controller
(30) and installed on the cover (20) so that the lever is operable by the thumb between
a first position corresponding to the first position of the controller (30) and a
second position corresponding to the second position of the controller (30).
4. The pneumatic tool according to claim 1 wherein the first and second grooves (31;
32) are on two opposite sides of the controller (30).
5. The pneumatic tool according to claim 1 wherein the first and second grooves (31;
32) both comprise an intake end (311; 321) for communication with the intake aperture
(153) and an outlet end (312; 322) for communication with the outlet aperture (154).
6. The pneumatic tool according to claim 5 wherein along the controller (30), the intake
and outlet ends (321; 322) of the second groove (32) are located between the intake
and outlet ends (311; 312) of the first groove (31).
7. The pneumatic tool according to claim 5 wherein the inlet (311) of the first groove
(31) is from the outlet (312) of the first groove (31) by a distance smaller than
the diameter of the intake aperture (153) of the second chamber (15).
8. The pneumatic tool according to claim 5 wherein the inlet (311) of the first groove
(31) is from the outlet (312) of the first groove (31) by a distance larger than the
diameter of the intake aperture (153) of the second chamber (15).
9. The pneumatic tool according to claim 1 wherein the shell (10) defines first and second
channels (16; 17) for communicating the first chamber (11) with the second chamber
(15).
10. The pneumatic tool according to claim 1 comprising a link (34) for connecting the
controller (30) to the lever (35).
11. The pneumatic tool according to claim 11 wherein the controller (30) comprises, on
an end, two ears (33) to which the link (34) is pivotally connected.
12. The pneumatic tool according to claim 11 wherein the link (34) is T-shaped, wherein
the lever (35) defines a T-shaped groove (351) for receiving the T-shaped link (34).
Amended claims in accordance with Rule 86(2) EPC.
1. A pneumatic tool operable with a single hand, the pneumatic tool comprising:
a shell (10) defining a first chamber (11) and a second chamber (15), the second chamber
(15) comprising an intake aperture (153) in communication with a portion of the first
chamber (11) and an outlet aperture (154) in communication with another portion of
the first chamber (11);
a cylinder (12) positioned in the first chamber (11);
a controller (30) movable in the second chamber (15) between a first position and
a second position, wherein the controller (30) comprises a first groove (31) and a
second groove (32) so that in the first position, the first groove (31) communicates
with a first channel aperture (151) in order to direct pressurized air to drive the
cylinder (12) in a first direction, and that in the second position, the second groove
(32) communicates with a second channel aperture (152) in order to direct pressurized
air to drive the cylinder (12) in a second direction; and
a cover (20) for sealing the first chamber (11) and the second chamber (15), the cover
(20) defining an opening (21) through which the controller (30) extends from the second
chamber (15) so that the controller (30) can be moved,
characterized in
that it comprises a lever (35) connected to the controller (30) and installed on the cover
(20) so that the lever is operable by the thumb between a first position corresponding
to the first position of the controller (30) and a second position corresponding to
the second position of the controller (30).
2. The pneumatic tool according to claim 1 comprising a handle (13) projecting from
the shell (10) and a trigger (14) in the handle (13) so that the trigger (14) is operable
by the index finger.
3. The pneumatic tool according to claim 1 wherein the first and second grooves (31;
32) are on two opposite sides of the controller (30).
4. The pneumatic tool according to claim 1 wherein the first and second grooves (31;32)
both comprise an intake end (321) for communication with the aperture (155) and an
outlet end (312;322) for communication with the intake aperture (153).
5. The pneumatic tool according to claim 4 wherein in the longitudinal direction of
the controller (30) the intake and outlet ends (321;322) of the second groove (32)
are located between the intake and outlet ends (311;312) of the first groove.
6. The pneumatic tool according to claim 4 wherein the intake end (311) of the first
groove (31) is spaced from the intake end (321) of the second groove (32) by a distance
smaller than the diameter of the aperture (155) of the second chamber (15) and wherein
the outlet end (312) of the first groove (31) is spaced from the outlet end (322)
of the second groove (32) by a distance smaller than the diameter of the intake aperture
(153) of the second chamber (15).
7. The pneumatic tool according to claim 4 wherein the intake end (311) of the first
groove (31) is spaced from the intake end (321) of the second groove (32) by a distance
larger than the diameter of the intake aperture (153) of the second chamber (15) and
wherein the outlet end (312) of the first groove (31) is spaced from the outlet end
(322) of the second groove (32) by a distance smaller than the diameter of the intake
aperture (153) of the second chamber (15).
8. The pneumatic tool according to claim 1 wherein the shell (10) defines first and
second channels (16;17) for communicating the first chamber (11) with the second chamber
(15).
9. The pneumatic tool according to claim 1 comprising a link (34) for connecting the
controller (30) to the lever (35).
10. The pneumatic tool according to claim 9 further comprising two ears (33) on an end
of the controller to which the link (34) is pivotally connected.
11. The pneumatic tool according to claim 10 wherein the link (34) is T-shaped, wherein
the lever (35) defines a T-shaped groove (351) for receiving the T-shaped link (34).