U.S. patent number RE44,057 [Application Number 12/547,142] was granted by the patent office on 2013-03-12 for locking mechanism for inclination adjustment of a blade of a cutting device.
This patent grant is currently assigned to Black & Decker Inc.. The grantee listed for this patent is Lee-Cheng Chang. Invention is credited to Lee-Cheng Chang.
United States Patent |
RE44,057 |
Chang |
March 12, 2013 |
Locking mechanism for inclination adjustment of a blade of a
cutting device
Abstract
A cutting device includes a base, a swivel seat rotatably
mounted on the base and having a first end and a second end, and a
blade holder releasably engaged with the second end of the swivel
seat. A blade is rotatably held by the blade holder. The blade
holder is pivotable relative to the swivel seat for cutting when
the blade holder is engaged with the second end of the swivel seat.
An inclination of the blade relative to the swivel seat is
adjustable when the blade holder is disengaged from the second end
of the swivel seat. An operative rod is mounted to the first end of
the swivel seat and operably connected to the blade holder for
controlling releasable engagement between the blade holder and the
swivel seat.
Inventors: |
Chang; Lee-Cheng (Taichung,
TW) |
Applicant: |
Name |
City |
State |
Country |
Type |
Chang; Lee-Cheng |
Taichung |
N/A |
TW |
|
|
Assignee: |
Black & Decker Inc.
(Newark, DE)
|
Family
ID: |
25445299 |
Appl.
No.: |
12/547,142 |
Filed: |
August 25, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
11297820 |
Dec 9, 2005 |
Re. 41857 |
|
|
Reissue of: |
09921339 |
Aug 2, 2001 |
6658977 |
Dec 9, 2003 |
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|
Current U.S.
Class: |
83/490; 83/473;
83/581; 83/471.3 |
Current CPC
Class: |
B23D
45/044 (20130101); B27B 5/29 (20130101); Y10T
83/8773 (20150401); Y10T 83/7705 (20150401); Y10T
83/7788 (20150401); Y10T 83/7697 (20150401) |
Current International
Class: |
B27B
5/20 (20060101) |
Field of
Search: |
;83/471.3,473,490,581 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Peterson; Kenneth E.
Attorney, Agent or Firm: Hunton & Williams LLP
Parent Case Text
.Iadd.This reissue patent application is a divisional of U.S.
Reissue application Ser. No. 11/297,820, filed Dec. 9, 2005, now
U.S. Pat. No. Re. 41,857, which is a reissue application of U.S.
Pat. No. 6,658,977, issued Dec. 9, 2003..Iaddend.
.Iadd.Notice: More than one reissue application has been filed for
the reissue of U.S. Pat. No. 6,658,977. The reissue applications
are: U.S. Reissue application Ser. No. 12/547,142, filed Aug. 25,
2009 (the present application), which is a divisional of U.S.
Reissue application Ser. No. 11/297,820 filed Dec. 9, 2005, now
U.S. Pat. No. Re. 41,857..Iaddend.
Claims
What is claimed is:
.[.1. A cutting device comprising: a base; a swivel seat rotatably
mounted on the base and having a first end and a second end; a
blade holder releasably engaged with the second end of the swivel
seat, with the blade holder adapted to rotatably hold a blade, with
the blade holder being pivotable about a first axis relative to the
swivel seat for cutting when the blade holder is engaged with the
second end of the swivel seat, with the blade holder being
pivotable about a second axis relative to the swivel seat for
adjusting an inclination of the blade holder relative to the swivel
seat, with the first axis being perpendicular to the second axis;
an operative rod rotatably mounted to the first end of the swivel
seat, the operative rod being operably connected to the blade
holder for controlling releasable engagement between the blade
holder and the swivel seat by the rotation of the operative rod to
allow adjustment of the inclination of the blade holder; and means
for controlling releasable engagement between the swivel seat and
the base, wherein said means for controlling releasable engagement
between the swivel seat and the base comprises a resilient
positioning plate including a first end secured to the swivel seat
and a second end for manual operation, the resilient positioning
plate further comprising a protrusion, the base comprising a
plurality of positioning notches, the protrusion of the resilient
positioning plate being releasably engaged with one of the
positioning notches of the base..].
.[.2. The cutting device as claimed in claim 1, further comprising
an actuating rod mounted to the first end of the swivel seat, the
actuating rod comprising a first end outside the first end of the
swivel seat for operation and a second end, the actuating rod and
the first end of the swivel seat being so arranged that the
actuating rod moves along a longitudinal direction thereof between
a locking position and an unlocking position, the second end of the
actuating rod pressing against the base to thereby prevent relative
rotation between the base and the swivel seat when the actuating
rod is in the locking position, the second end of the actuating rod
being disengaged from the base when the actuating rod is in the
unlocking position..].
.[.3. The cutting device as claimed in claim 2, wherein the
actuating rod comprises a threaded section, the swivel seat
comprising a nut securely mounted therein, the nut being threadedly
engaged with the threaded section of the actuating rod..].
.[.4. The cutting device as claimed in claim 2, further comprising
an operative member mounted to the first end of the actuating rod
and slidable along the actuating rod between an engaging position
and a disengaging position, the operative member comprising a drive
gear securely mounted thereon to rotate therewith, the operative
rod comprising a driven gear securely mounted thereon to rotate
therewith, the drive gear meshing with the driven gear when the
operative member is in the engaging position, the drive gear being
disengaged from the driven gear when the operative member is in the
disengaging position..].
.[.5. The cuffing device as claimed in claim 4, wherein the
operative member comprises a compartment in a first end thereof, a
wall defining the compartment including a positioning groove, the
operative member further comprising a hole in a second end thereof,
the hole being communicated with the positioning groove, a
positioning pin being securely mounted to the first end of the
actuating rod, the actuating rod extending through the hole of the
operative member with the first end of the actuating rod located in
the compartment, the positioning pin being positioned in the
positioning groove of the operative member when the operative
member is in the disengaging position, the positioning pin being
disengaged from the positioning groove of the operative member when
the operative member is in the engaging position..].
.[.6. The cutting device as claimed in claim 5, wherein the
actuating rod is moved between the locking position and the
unlocking position when the operative member is in the disengaging
position and when the first end of the operative member is
turned..].
.[.7. The cutting device as claimed in claim 5, wherein the
actuating rod comprises a threaded section, the swivel seat
comprising a wall having a hole, a nut being securely mounted in
the hole of the wall of the swivel seat, the nut being threadedly
engaged with the threaded section of the actuating rod..].
.[.8. The cutting device as claimed in claim 7, further comprising
means for returning the operative member from the engaging position
to the disengaging position..].
.[.9. The cutting device as claimed in claim 8, wherein said
returning means comprises an elastic element attached between the
nut and the second end of the operative member..].
.[.10. A cutting device comprising: a base; a swivel seat rotatably
mounted on the base and having a first end and a second end; a
blade holder releasably engaged with the second end of the swivel
seat, with the blade bolder adapted to rotatably hold a blade, with
the blade holder being pivotable about a first axis relative to the
swivel seat for cutting when the blade holder is engaged with the
second end of the swivel seat, with the blade holder being
pivotable about a second axis relative to the swivel seat for
adjusting an inclination of the blade holder relative to the swivel
seat, with the first axis being perpendicular to the second axis;
and an operative rod rotatably mounted to the first end of the
swivel seat, the operative rod being operably connected to the
blade holder for controlling releasable engagement between the
blade holder and the swivel seat by the rotation of the operative
rod to allow adjustment of the inclination of the blade holder,
with the blade holder being pivotably mounted to the swivel seat by
a locking member, wherein the operative rod extends from the first
end of the swivel seat through the second end of the swivel seat
and through the locking member, the operative rod comprising a
first end and a second end that is outside the second end of the
swivel seat, a pressing member being securely mounted to the second
end of the operative rod to move therewith; the operative rod and
the swivel seat being so arranged that rotation of the operative
rod causes longitudinal movement of the operative rod and the
pressing member along a longitudinal axis of the operative rod;
wherein the pressing member is moved to a first position pressing
the locking member against the second end of the swivel seat when
the operative rod is turned in a first direction, thereby
preventing adjustment in the inclination angle of the blade; and
wherein the pressing member is moved to a second position not
pressing the locking member against the second end of the swivel
seat when the operative rod is turned in a second direction
opposite to the first direction, thereby allowing rotational
movement of the locking member and the blade holder relative to the
swivel seat for proceeding with adjustment in the inclination angle
of the blade..].
.[.11. The cutting device as claimed in claim 10, wherein the first
end of the operative rod is outside the first end of the swivel
seat, with the cutting device further comprising a turning member
mounted to the first end of the operative rod for turning the
operative rod..].
.[.12. The cutting device as claimed in claim 10, wherein the
operative rod comprises a threaded section, the swivel seat
comprising a nut securely mounted therein, the nut being threadedly
engaged with the threaded section of the operative rod..].
.[.13. The cutting device as claimed in claim 10, further
comprising an engaging member having a first end securely mounted
to the second end of the swivel seat, an intermediate section, and
a second end, the locking member being rotatably mounted around the
intermediate section of the engaging member and slidable along a
longitudinal direction of the engaging member when the pressing
member is in the second position..].
.[.14. The cutting device as claimed in claim 13, wherein the
second end of the swivel seat comprises a screw hole and the first
end of the engaging member comprises an outer threading for
engaging with the screw hole..].
.[.15. The cutting device as claimed in claim 13, wherein the
second end of the engaging member comprises an outer threading,
with the cutting device further comprising a nut engaged with the
outer threading of the second end of the engaging member for
preventing disengagement of the locking member from the engaging
member..].
.Iadd.16. A cutting device comprising: a base; a swivel seat
mounted on the base and having a first end and a second end
opposite the first end, the swivel seat having an engaging section
at the second end thereof; a locking member in releasable
engagement with the engaging section; a blade holder releasably
engaged with the second end of the swivel seat through the locking
member so that the blade holder is pivotable about an axis relative
to the swivel seat for adjusting an inclination of the blade holder
relative to the swivel seat; an operative member at the first end
of the swivel seat, the operative member being pushed towards the
second end of the swivel seat to mesh a drive gear with a driven
gear when locking or unlocking the locking member such that the
inclination of the blade can be adjusted; and means for controlling
releasable engagement between the swivel seat and the base
comprising a resilient positioning plate including a first end
secured to the swivel seat and a second end for manual operation,
the resilient positioning plate further comprising a protrusion,
the base comprising a plurality of positioning notches, the
protrusion of the resilient positioning plate being releasably
engaged with one of the positioning notches of the
base..Iaddend.
.Iadd.17. A cutting device comprising: a base; a swivel seat
mounted on the base and having a first end and a second end
opposite the first end, the swivel seat having an engaging section
at the second end thereof; a locking member in releasable
engagement with the engaging section; a blade holder releasably
engaged with the second end of the swivel seat through the locking
member so that the blade holder is pivotable about an axis relative
to the swivel seat for adjusting an inclination of the blade holder
relative to the swivel seat; an operative member at the first end
of the swivel seat, a portion of the operative member being
positioned closer to the second end of the swivel seat to mesh a
drive gear with a driven gear when locking or unlocking the locking
member such that the inclination of the blade can be adjusted; and
means for controlling releasable engagement between the swivel seat
and the base comprising a resilient positioning plate including a
first end secured to the swivel seat and a second end for manual
operation, the resilient positioning plate further comprising a
protrusion, the base comprising a plurality of positioning notches,
the protrusion of the resilient positioning plate being releasably
engaged with one of the positioning notches of the
base..Iaddend.
.Iadd.18. A cutting device comprising: a base; a swivel seat
mounted on the base and having a first end and a second end
opposite the first end, the swivel seat having an engaging section
at the second end thereof; a locking member in releasable
engagement with the engaging section; a blade holder releasably
engaged with the second end of the swivel seat through the locking
member so that the blade holder is pivotable about an axis relative
to the swivel seat for adjusting an inclination of the blade holder
relative to the swivel seat; an operative member at the first end
of the swivel seat, the operative member operably connected to the
blade holder for controlling releaseable engagement between the
locking member and the engaging section of the swivel seat, the
operative member having a first position and a second position in
which at least a portion of the operative member is closer to the
swivel seat in the second position than in the first position, the
operative member meshing a drive gear with a driven gear in the
second position to allow locking or unlocking the locking member
such that the inclination of the blade can be adjusted; and means
for controlling releasable engagement between the swivel seat and
the base comprising a resilient positioning plate including a first
end secured to the swivel seat and a second end for manual
operation, the resilient positioning plate further comprising a
protrusion, the base comprising a plurality of positioning notches,
the protrusion of the resilient positioning plate being releasably
engaged with one of the positioning notches of the
base..Iaddend.
.Iadd.19. A method for adjusting the inclination angle of a blade
holder in a cutting device, wherein the cutting device comprises a
swivel seat mounted on the base and having a first end and a second
end opposite the first end, the swivel seat having an engaging
section at the second end thereof, a locking member in releasable
engagement with the engaging section, a blade holder releasably
engaged with the second end of the swivel seat through the locking
member so that the blade holder is pivotable about an axis relative
to the swivel seat for adjusting an inclination of the blade holder
relative to the swivel seat, an operative member at the first end
of the swivel seat used when adjusting the inclination angle of the
blade holder, the operative member having a first position and a
second position in which at least a portion of the operative member
is closer to the swivel seat in the second position than in the
first position, and means for controlling releasable engagement
between the swivel seat and the base comprising a resilient
positioning plate including a first end secured to the swivel seat
and a second end for manual operation, the resilient positioning
plate further comprising a protrusion, the base comprising a
plurality of positioning notches, the protrusion of the resilient
positioning plate being releasably engaged with one of the
positioning notches of the base, the method comprising: pushing at
least a portion of the operative member from the first position to
the second position in the direction of the second end of the
swivel seat to mesh a drive gear with a driven gear; adjusting the
inclination angle of the blade holder; and returning the operative
member to the first position..Iaddend.
.Iadd.20. The method according to claim 19 further comprising the
step of disengaging the locking member from the engaging section of
the swivel seat..Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a locking mechanism for
inclination adjustment of a blade of a cutting device.
2. Description of the Related Art
A typical cutting device comprises a base and a blade holder. When
adjustment in an inclination of the cutting plane of the blade
relative to a horizontal plane is required, an adjusting member
located on a rear side of the base is operated to provide a gap
between the blade holder and the base, thereby allowing adjustment
in the inclination angle (or tilt angle) of the blade holder.
Nevertheless, during such an adjustment, the operator's hand is
close to and thus might be injured by the blade.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a
locking mechanism for inclination adjustment of a blade of a
cutting device, wherein the inclination (or tilt angle) of the
blade (i.e., the angle between the cutting plane and a horizontal
plane) can be adjusted by operating an operative end of the locking
mechanism that is located in front of the base, thereby eliminating
potential injury to the operator. In particular, the locking
mechanism comprises an operative rod for controlling engagement
between the swivel seat and the blade holder. Thus, the blade
holder together with the blade can be pivoted to a desired
inclination when the swivel seat and the blade holder are
disengaged from each other. The operative end for moving the
operative rod is located in front of the swivel seal, thereby
avoiding potential injury to the operator.
In accordance with a first aspect of the invention, a cutting
device comprises a base having a first end and a second end
opposite to the first end. A blade holder is releasably engaged
with the second end of the base and rotatably holds a blade. The
blade holder is pivotable relative to the base for cutting when the
blade holder is engaged with the second end of the base. An
inclination of the blade relative to the base is adjustable when
the blade holder is disengaged from the second end of the base. An
operative rod is mounted to the first end of the base and operably
connected to the blade holder for controlling releasable engagement
between the blade holder and the base.
In accordance with a second aspect of the invention, a cutting
device comprises a base, a swivel seat rotatably mounted on the
base and having a first end and a second end, and a blade holder
releasably engaged with the second end of the swivel seat. A blade
is rotatably held by the blade holder. The blade holder is
pivotable relative to the swivel seat for cutting when the blade
holder is engaged with the second end of the swivel seat. An
inclination of the blade relative to the swivel seat is adjustable
when the blade holder is disengaged from the second end of the
swivel seat. An operative rod is mounted to the first end of the
swivel seat and operably connected to the blade holder for
controlling releasable engagement between the blade holder and the
swivel seat.
Other objects, advantages, and novel features of the invention will
become more apparent from the following detailed description when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a cutting device in accordance with
the present invention.
FIG. 2 is an exploded perspective view of the cutting device in
accordance with the present invention.
FIG. 3 is a sectional view taken along plane 3-3 in FIG. 1.
FIG. 4 is a sectional view taken along plane 4-4 in FIG. 3.
FIG. 5 is a view similar to FIG. 3, illustrating inclination
adjustment of a cutting plane of the cutting device.
FIG. 6 is a sectional view similar to FIG. 3, illustrating a
modified embodiment of the cutting device in accordance with the
present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 through 3, a cutting device 10 in accordance
with the present invention generally includes a swivel seat 20
mounted on a base 11 and rotatable relative to the base 11 about a
vertical axis orthogonal in the base 11. A blade holder 30 is
pivotally mounted via a locking member 40 to a rear end of the
swivel seat 20 for proceeding with a cutting function by a blade 31
rotably held by the blade holder 30, which will be described in
detail later. The base 11 comprises an arc 12 on which a scale 13
is provided. Plural positioning notches 14 spaced by regular
intervals are defined in an underside of the arc 12.
The swivel seat 20 comprises a cutting groove 21 (FIG. 2) through
which the blade 31 is movable for cutting purpose. The rear end of
the swivel seat 20 provides an engaging section 23 comprising a
screw hole 231 and a hole 232. Formed on the front end of the
swivel seat 20 is a mounting section 22. The mounting section 22
comprises a first longitudinal hole 221 and a second longitudinal
hole 222 that extend along a direction parallel to a cutting plane
of the blade 31. The mounting section 22 further comprises a window
223 having a pointer 24 received therein for reading the scale 13.
The mounting section 22 further comprises a wall 224 delimiting a
compartment 225 in the mounting section 22.
The locking member 40 is releasably engaged with the engaging
section 23 of the swivel seat 20. The blade holder 30 is engaged
with the locking member 40 and pivotable about a pivotal axis 46
(FIG. 1) for cutting by means of operating a handle 32 on the blade
holder 30. It is noted that the locking member 40 is movable
between a locking position and an unlocking position. In the
locking position, the locking member 40 presses against the
engaging section 23 of the swivel sear 20 and is thus fixed in
place. The locking member 40 and the blade holder 30 cannot rotate
about an engaging member 43 defining a pivotal axis 48 (FIG. 3) of
the locking member 40 parallel to the first longitudinal hole 221
of the swivel seat 20; namely, adjustment of the inclination of the
blade 31 is not allowed. But the blade holder 30 can be pivoted
relative to the locking member 40 about the axis 46. In the
unlocking position, the locking member 40 is disengaged from the
engaging section 23 of the swivel seat 20 and thus rotatable,
thereby allowing adjustment in the inclination of the blade 31 by
means of turning the locking member 40 and the blade holder 30
about the pivotal axis 48 of the locking member 40.
A hole 41 is defined in a side of the locking member 40 that faces
the engaging section 23 of the swivel seat 20. The engaging member
43 comprises a first threaded end 431 threadedly engaged in the
screw bole 231 of the engaging section 23 of the swivel seat 20, a
second threaded end 432, and an intermediate section 433 slidably
and rotatably received in the hole 41 of the locking member 40. A
nut 44 is engaged on the second threaded end 432 to prevent
disengagement of the locking member 40. Thus, the locking member 40
is slidable and rotatable relative to the engaging section 23 of
the swivel seat 20 in the unlocking position, which will be further
described later.
A positioning device 50 is provided to position the swivel seat 20.
The positioning device 50 comprises a resilient positioning plate
51 and a reinforcing plate 52. The positioning plate 51 comprises
two holes 53 in a first end thereof, two wings 54 extending upright
from a second end thereof, and a protrusion 55 on an intermediate
portion thereof. Two bolts 57 are respectively extended through two
holes 56 in the reinforcing plate 52 and the holes 53 in the
positioning plate 51 and then threadedly engaged in two screw holes
25 in an underside of the swivel seat 20. The positioning plate 51
is thus positioned below the mounting section 22 of the swivel seat
20 with the protrusion 55 engaging with one of the positioning
notches 14 of the base 11 for preventing rotational movement of the
swivel seat 20 relative to the base 11.
A locking mechanism 60 is used to control engagement between the
locking member 40 and the engaging section 23 of the swivel seat
20. In this embodiment, the locking mechanism 60 comprises an
operative member 61, an actuating rod 62, and an operative rod 63.
The operative rod 63 comprises a first end 636 received in the
first longitudinal hole 221 of the mounting section 22 and a second
end 635 extending beyond the locking member 40 after passing
through the hole 232 in the engaging section 23 of the swivel seat
20 and a hole 49 in the locking member 40. A nut 631 is securely
mounted in the engaging section 23 of the swivel seat 20 and
threadedly engaged with a threaded section 638 of the operative rod
63. Thus, the operative rod 63 moves along a longitudinal axis
thereof when it is turned.
A pressing cap 634 is mounted to the second end 635 of the
operative rod 63, and a pin 632 is extended through a transverse
hole 637 in the pressing cap 634 and a transverse pinhole 633 in
the second end 635 of the operative rod 63. By such an arrangement,
the pressing cap 634 and the operative rod 63 move longitudinally
away from the locking member 40 when the operative rod 63 is turned
in a direction, e.g., clockwise, such that the locking member 40 is
no longer pressed against by the pressing cap 634. As a result, the
locking member 40 is no longer in frictional contact with the
engaging section 23 of the swivel seat 20. Pivotal movement of the
locking member 40 is limited between two spaced blocks 42 on an
inner periphery of the locking member 40.
To the contrary, when the operative rod 63 is turned in an opposite
direction, e.g., counterclockwise, the locking member 40 will be
moved toward the engaging section 23 by the pressing cap 634 and
finally presses against the engaging section 23 for preventing
rotation of the locking member 40. Namely, the locking member 40 is
in frictional contact with the engaging section 23 of the swivel
seat 20 when in the locking position. Thus, the locking member 40
can be disengaged from or engaged with the engaging section 23 of
the swivel seat 20 by means of turning the operative rod 63. When
the locking member 40 is in the unlocking position, the operator
may grasp the handle 32 on the blade holder 30 and pivot the blade
holder 30 and the locking member 40 about the pivotal axis 48 of
the locking member 40 to the desired inclination. The sliding and
rotating contact between the intermediate portion 433 of the
engaging member 43 and the locking member 40 allows such
adjustment. After adjustment in the inclination (or tilt angle) of
the blade 31, the operative rod 63 is turned in the opposite
direction. The operative rod 63 can be turned by means of operating
the operative member 61.
As illustrated in FIG. 3, the operative member 61 comprises a
compartment 611 in an end thereof, a wall defining the compartment
611 including a positioning groove 612. The other end 613 of the
operative member 61 extends into the compartment 225 of the
mounting section 22 of the swivel seat 20. It is noted that a hole
615 is defined in the other end 613 of the operative member 61 and
has a first end communicated with the positioning groove 612 of the
operative member 61 and a second end communicated with the
compartment 225 of the mounting section 22 of the swivel seat 20.
The other end 613 of the operative member 61 extends through a
lining member or sleeve 64 located in the second longitudinal hole
222 of the mounting section 22 of the swivel seat 20. A drive gear
65 is mounted on the other end 613 of the operative member 61 by
means of force-fitting engagement with two chamfered faces 614 of
the outer end 613 of the operative member 61, and a C-clip 616 is
provided to securely retain the drive gear 65 on the other end 613
of the operative member 61.
The actuating rod 62 extends through the hole 615 of the operative
member 61 and comprises a first end 624 in the compartment 611 of
the operative member 61 and a threaded second end 625 threadedly
engaged with an inner threading (not labeled) of the sleeve 619,
which, in turn, is securely located in a hole 226 in the wall 224
of the swivel seat 20 by a C-clip (not labeled). A positioning pin
622 is extended through a transverse pinhole 621 in the first end
624 of the actuating rod 62 and releasably engaged in the
positioning groove 612 of the operative member 61. A pressing
member 66 is partially engaged in a screw hole 623 defined in an
end face of the second end 625 of the actuating rod 62. A spring
618 is mounted around the actuating rod 62 and attached between two
sleeves 617 that are mounted around the actuating rod 62. It is
noted that the drive gear 65 on the actuating rod 62 is disengaged
from a driven gear 67 securely mounted on the operative rod 63 when
adjustment in the inclination is not required.
Referring to FIG. 3, when adjusting angular position of the swivel
seat 20, the operative member 61 is turned in a direction, which,
in turn, causes rotation of the actuating rod 62 in the same
direction, as the positioning pin 622 of the actuating rod 62 is
positioned in the positioning groove 612 of the operative member
61. The pressing member 66 on the actuating rod 62 that initially
presses against an outer peripheral wall of the arc 12 of the base
11 is now disengaged from the peripheral wall of the arc 12.
Referring to FIG. 4, the operator then pushes the wings 54 downward
to disengage the protrusion 55 of the positioning plate 51 from the
positioning notch 14 of the base 11. At this time, the swivel seat
20 is rotatable relative to the base 11 for adjustment in the
angular position of the swivel seat 20 relative to the base 11.
After adjustment, the wings 54 of the positioning plate 51 are
released, the protrusion 55 of the positioning plate 51 returns to
its initial position under the action of resiliency of the
positioning plate 51 and thus engages with an associated one of the
positioning notches 14 of the base 11. Then, the operative member
61 is turned in an opposite direction, which, in turn, causes
rotation of the actuating rod 62 until the pressing member 66
presses against the outer peripheral wall of the arc 12 of the base
11, thereby assisting in positioning between the swivel seat 20 and
the base 11. The angular position of the swivel seat 20 is
indicated by the pointer 24 and the scale 13, which can be read via
the window 223.
Referring to FIG. 5, when adjusting the inclination of the blade
31, the operative member 61 is pushed inward until the drive gear
65 meshes with the driven gear 67. The positioning pin 622 of the
actuating rod 62 is no longer positioned in the positioning groove
612 of the operative member 61. Next, the operative member 61 is
turned to drive the operative rod 63 in a direction, e.g.,
clockwise. The locking member 40 is no longer pressed against the
engaging section 23 of the swivel seat 20 to thereby allow
adjustment in inclination of the blade 31 by means of moving the
handle 32 of the blade holder 30, as mentioned above. Next, the
operative member 61 is turned in on opposite direction to turn the
operative rod 63 counterclockwise, thereby urging the pressing cap
634 to press the locking member 40 against the engaging section 23
of the swivel seat 20, as mentioned above. After adjustment, the
operative rod 63 is returned to its initial position under the
action of the spring 618. The operative rod 63 will not be turned
even if the operative member 61 is rotated, as the drive gear 65
disengages from the driven gear 67.
FIG. 6 illustrates a modified embodiment of the invention, wherein
the return spring 618 and corresponding elements are omitted. In
addition, the drive gear 65 and the driven gear 67 are also
omitted. Namely, the operative rod 63 and the operative member 61
are independent from each other. Further, a turning member 639
(e.g., a nut) is mounted on the exposed first end of the operative
rod 63 that is distal to the locking member 40 and the engaging
section 23 of the swivel seat 20. The turning member 639 allows
rotational operation of the operative rod 63 for controlling
engagement between the locking member 40 and the engaging section
23 of the swivel seat 20.
According to the above description, it is appreciated that
adjustment in the inclination of the blade 31 and the angular
position of the swivel seat 20 can be achieved easily without the
risk of injury to the operator, as the operative end for the
operative member 61 and the operative end for the operative rod 63
are distal to the locking member 40 and the engaging section 23 of
the swivel seat 20.
When adjustment in the angular position of the swivel seat 20 is
not required, the swivel seat 20 may be integral with the base 11.
At this time, the locking member 40 and the blade holder 30 are
directly associated with the base 11.
Although the invention has been explained in relation to its
preferred embodiment, it is to be understood that many other
possible modifications and variations can be made without departing
from the scope of the invention as hereinafter claimed.
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