Note: Descriptions are shown in the official language in which they were submitted.
CA 02296863 2000-O1-21
VENETIAN BLIND CUTTING MACHINE
FIELD OF THE INVENTION
The present invention relates generally to a Venetian blind, and
more particularly to a machine for cutting the Venetian blind.
BACKGROUND OF THE INVENTION
The Venetian blinds are generally made in quantity by the makers
according to the standard specifications and are then shipped to the
wholesale outlets for distribution. In other words, the Venetian blinds are
not custom-made for the consumer. In view of the windows of the houses
or buildings being of various specifications, the Venetian blinds must be
cut to order to meet the demand of the consumer.
As shown in FIG. 1, a prior art hydaulic machine is manually
operated to cut the Venetian blind according to the specifications
demanded by a client. The manual operation is inefficient at best in light
of the cutting of the Venetian blind being attained by the shear
destruction. Such manual operation is feasible when the Venetian blind is
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made of an expandable material, such as aluminium. A smooth cutting
surface of the Venetian blind can not be attained if the Venetian blind is
made of tough material such as a wood or fiber containing material, or a
rigid and fragile material such as PVC.
As shown in FIGS. 2 and 3, another prior art machine for cutting
the Venetian blind is composed of a machine stand 1 on which a support
frame 2 is mounted. The support frame 2 is provided at one end thereof
with a clamping device 3 for holding a Venetian blind securely. The
machine stand 1 is provided at the bottom thereof with a cutting device 4
capable of linear reciprocating motion and having a blade 4a which is
partially exposed from the top of the machine stand 1 to facilitate the
cutting of both ends of the Venetian blind. However, the blade 4a in
motion has a machining force F, which brings about an outward push
force Fa and a downward cutting force Fb, as shown in FIG. 4. The slats
of the Venetian blind are apt to be pushed by the outward push force Fa,
thereby causing the slats to be loosened. Under such a circumstance as
described above, it is difficult to cut the Venetian blind such that the cut
surface is smooth. In addition, the saw dust is caused by the machining
force F to fall on the saw teeth of the blade 4a. As a result, the cutting
efficiency of the blade 4a is seriously undermined. Moreover, the motor
of the cutting machine is located under the blade 4a and is therefore
vulnerable to malfunction which is caused by the accumulation of the
saw dust around the axis of the motor.
SUMMARY OF THE INVENTION
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In accordance with one embodiment of the present
invention, there is provided a machine for cutting a
Venetian blind comprising: a machine housing; a cutting
device mounted in the machine housing; a blind supporting
frame mounted on the machine housing for holding the
Venetian blind; a clamping device mounted on the machine
housing at a first end of the blind supporting frame for
holding a first end of the Venetian blind in a cutting path
of the cutting devices a circular blade on the cutting
device driven in a linear reciprocating motion on guide rods
which forms the cutting path; the guide rods being engaged
on an upper side of the machine housing; the upper side of
the machine housing comprising a front portion having a
pivotable protective cover being disposed adjacent to the
blade and parallel to the cutting path and side portions
being disposed on each end of the cutting path and
perpendicular to the front portion; wherein at least an
upper half portion of the blade above an axis of rotation is
entirely enclosed by the upper side of the machine housing
when the protective cover is closed; wherein the axis of
rotation through a center of the circular blade is spaced
above and parallel to a longitudinal length of the Venetian
blind to create a downward and inward cutting force on slats
of the Venetian blind which pull the slats together when the
Venetian blind is cut.
The present invention provides, in preferred
embodiments, a Venetian blind cutting machine comprising a
machine stand on which a cutting device and a clamping
device are mounted. The cutting device has a blade
executing the cutting of the Venetian blind in a linear
reciprocating manner along a cutting path. The Venetian
blind is held securely by the clamping device such that one
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end of the Venetian blind is extended into the cutting path.
The blade has a cutting side which is one quarter of a
circle, and is formed by a cutting horizontal center line
passing the pivotal center of the blade, and a cutting
vertical center line. The cutting side is located at the
lower half portion of the cutting horizontal center line
such that a downward cutting force and an inward cutting
force are brought about at the time when the Venetian blind
is located at the cutting side of the blade and is being
cut.
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BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic view of the manual operation of a prior
art machine for cutting the Venetian blind.
FIG. 2 shows a perspective view of another prior art machine for
cutting the Venetian blind.
FIG. 3 shows a side view of the prior art machine as shown in FIG.
2.
FIG. 4 shows a schematic view of the prior art machine at work to
cut the Venetian blind.
FIG. 5 shows a perspective view of a preferred embodiment of the
present invention.
FIG. 6 shows a side view of the preferred embodiment of the
present invention.
FIG. 7 shows a rear view of the preferred embodiment of the
present invention.
FIG. 8 shows a flow chart of the operation control of the blade by a
controller of the preferred embodiment of the present invention.
FIG. 9 shows a schematic view of the blade of the present
invention in operation to execute the cutting of the Venetian blind.
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FIG. 10 shows a schematic view of the clamping device
of another preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIGS. 5, 6 and 7, a Venetian blind cutting
machine 100 embodied in the present invention comprises a
machine stand or housing 10 on which a cutting device 20, a
clamping device 30, and a blind supporting frame 40 are
mounted.
The cutting device 20 has a blade 21 capable of a
linear reciprocating motion along a cutting path to execute
the cutting of a Venetian blind 200 which is securely held
by the clamping device 30 and is supported on the blind
supporting frame 40.
The machine housing 10 is provided in the lower section
of the front side thereof with a blind guiding port 11 at
which the blind supporting frame 40 is connected. The blind
supporting frame 40 has a U-shaped cross section and a slot
41 in which an urging member 12 is disposed such that the
urging member 12 urges the side of the Venetian blind 200.
The urging member 12 is provided in the upper edge thereof
with a receiving slot 121. The machine housing 10 is
provided at the bottom thereof with a collection device 13
for collecting the saw dust. The machine housing 10 is
provided with a protective cover 14 fastened pivotally
therewith such that the protective cover 19 is located over
the guiding port 11, and that the protective cover 14 can be
lifted to facilitate the cleaning of the interior of the
machine housing 10. The machine housing 10 is further
provided with a safety switch 15 located at the place where
the safety switch 15 is touched by the protective cover 14
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at the time when the protective cover 14 is rotated from its
open position shown in Fig. 5 to its closed position in Fig.
6. The preferred embodiment of the present invention is
provided with a proximity switch. When the protective cover
14 is rotated to be closed, the safety switch 15 acts to
bring about a predetermined effect.
As shown in FIG. 6, the cutting device 20 comprises two
guide rods 22, a guide threaded rod 23, a slide seat 24, a
transmission motor 2.5, and a drive motor 26. The
transmission motor 25 and the drive motor 26 are controlled
by a controller 50 mounted on the top of the machine stand
10.
The guide rods 22 are perpendicular to the feeding
direction of the Venetian blind 200 and are mounted across
the upper portion of the interior of the machine stand 10.
The guide threaded rod 23 is disposed between the two guide
rods 22 such that the guide threaded rod 23 is parallel to
the guide rods 22.
The slide seat 24 is fitted with the two guide rods 22
and is driven by the guide threaded rod 23 to displace back
and forth.
The transmission motor 25 is mounted on the top of the
machine stand 10 to drive the guide threaded rod 23 to turn,
so as to actuate the slide seat 24 to displace at a constant
feed speed.
The drive motor 26 is mounted at the bottom of the
slide seat 24. The spindle of the drive motor 26 is
provided at one end thereof with a
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saw blade 21 fastened therewith for cutting the Venetian blind 200. The
saw blade 21 has a cutting side which is one quarter of a circle formed by
a cutting horizontal center line H passing the pivoting center of the saw
blade 21, and a cutting vertical center line V. The cutting side is located
at the lower half portion of the cutting horizontal center line H, so as to
enable the saw blade 21 to execute the cutting of the Venetian blind 200
by the cutting side thereof. The drive motor 26 of the preferred
embodiment of the present invention is a direct current motor capable of
regulating the revolving speed of the saw blade 21 as the voltage is
changed.
The clamping device 30 is mounted in the machined stand 10 and
is contiguous to the guiding port 11. The clamping device 30 is formed of
a clamping seat 31, a threaded rod 32, an adjustment block 33, and a
rotary wheel 34. The clamping seat 31 has a U-shaped cross section and
is connected with the blind supporting frame 40 for keeping the Venetian
blind 200 to be cut. The adjustment block 33 is driven to displace by the
threaded rod 32 via the rotary wheel 34 for holding the Venetian blind
200. The clamping seat 31 is provided with a frame slot 311 opposite in ,
location to the receiving slot 121 of the urging member 12.
The machine stand 10 is provided in one side thereof with a
measuring member 60 which is formed of a fastening seat 61, a slide
block 62, an arresting plate 63, and a touch piece 64. The fastening block
61 is of an inverted U-shaped construction and is provided with two
guide rods 65 disposed horizontally between the two side plates of the
fastening block 61. The fastening seat 61 is further provided on the top
thereof with a scale 611. The slide block 62 is capable of horizontal
displacement along each guide rod 65. The arresting plate 63 is fastened
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with the slide block 62 for stopping the end edge of the Venetian blind
200. The touch piece 64 is movably fastened with the slide block 62 such
that the touch piece 64 is turned to enable one end thereof to urge one
side of the fastening seat 61 at the time when the slide block 62 is
adjusted and located in accordance with the scale 611. As a result, the
desired length of the Venetian blind 200 can be set with certainty.
In operation, the desired size of the Venetian blind 200 is first set
by moving the slide block 62 under the direction of the scale 611 before
the touch piece 64 is turned such that one end of the touch piece 64 urges
the side of the fastening seat 61, thereby locating the arresting plate 63 at
a position. Before the Venetian blind 200 is cut, the headrail 201 of the
Venetian blind 200 is provided therein with a bracing tube A of a plastic
material, which is intended to prevent the headrail 201 from being
deformed by the cutting action. Thereafter, the Venetian blind 200 is
placed on the slot 41 of the blind supporting frame 40 such that the
Venetian blind 200 is pushed to move forward by the urging member 12.
As soon as the front side of the Venetian blind 200 comes in contact with
the arresting plate 63, the rotary wheel 34 turns to enable the adjustment
block 33 to clamp the Venetian blind 200, which is then ready to be cut.
As shown in FIG. 8, the cutting speed of the saw blade 21 is set
manually or automatically by the controller 50. If the manual operation is
chosen, the feed rate and the revolution per minute (RPM) of the saw
blade 21 are regulated by controlling the transmission motor 25 and the
drive motor 26. The execution of the cutting of the Venetian blind 200 is
attained by the linear displacement of the saw blade 21 at the adjusted
feed rate in conjunction with the adjusted revolution of the saw blade 21.
The transmission motor 25 and the drive motor 26 can be automatically
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controlled by the controller 50. The controller 50 has a control seat 51
into which the appropriate reference data are entered before the
transmission motor 25 and the drive motor 26 are started simultaneously
to adjust the feed rate and the revolution of the saw blade 21 in
accordance with the nature of the material of which the Venetian blind is
made. For example, the Venetian blind 200 is made of a wood material
or a material containing fibers, the revolution per minute (RP1V1) of the
saw blade 21 must be faster, whereas the feed rate of the saw blade 21
must be slower. If the Venetian blind is made of a relatively fragile
material, such as PVC, the revolution per minute of the saw blade 21
must be appropriately slowed down or kept constant, whereas the feed
rate of the saw blade 21 must be appropriately faster.
As shown in FIG. 9, the drive motor 26, which regulates the
revolution of the saw blade 21, is inverted to enable the arcuate cutting
side of the front section of the lower half portion of the saw blade 21 to
excute the cutting of the Venetian blind 200. The saw blade 21 has a
cutting action force F, which brings about an inward cutting component
of force Fx and a downward cutting component of force Fy. These two
forces Fx and Fy bring about a downward pressure exerting on the slats
of the Venetian blind 200 being cut, as well as the effect of pulling the
slats together. As a result, the saw dust is allowed to fall into the
collection device 13 in the downward tangent direction, thereby
preventing the cut surfaces of the Venetian blind from being interfered
by the saw dust. In addition, the operator of the machine of the present
invention is provided with protection against the saw dust by the
protective cover 14 which is made of a transparent material. In the event
that the protective cover 14 is inadvertently lifted, the safety switch 15 is
triggered to cut off the power supply to the controller 50, thereby
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resulting in the temporary interruption of the operation of
the saw blade 21.
Before the cutting of the Venetian blind 200 is
started, a decorative plate (not shown in the drawings) is
arranged between the receiving slot 121 of the urging member
12 and the frame slot 311 of the clamping seat 31. The
decorative plate is cut along the Venetian blind 200 for use
in decorating the headrail 201 of the Venetian blind 200.
In order to enhance the collection of the saw dust, the
machine stand 10 is provided with a suction device
contiguous to the saw blade 21 for attaining a forcible
collection of the saw dust.
As shown in FIG. 10, the clamping device of another
preferred embodiment of the present invention has a clamping
seat 31 which is provided with a guide block 35 having a
plurality of rail slots 351. The rail slots 351 are
intended to guide the headrail 201 of the Venetian blind
200.
The saw dust produced in the operation of cutting the
Venetian blind 200 by the machine of the present invention
does not interfere with the cut surfaces of the Venetian
blind 200 in view of the fact that the cutting is done by
the lower arcuate cutting side of the saw blade 21. In
addition, the feed rate and the revolution speed of the saw
blade 21 are regulated by the controller 50 in accordance
with the nature of the material of which the Venetian blind
is made. The drive motor 26 is a direct current motor,
which is small in volume and relatively quiet while in
operation. As a result, the saw blade 21 in operation is
relatively quiet. The present invention may be used as a
finishing tool to cut a wood or
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PVC material. The present invention is provided with a means to
accommodate a decorative plate, which is cut along with the Venetian
blind. It is therefore readily apparent that the present invention is
versatile in design.
The embodiments of the present invention described above are to
be regarded in all respects as being merely illustrative and not restrictive.
Accordingly, the present invention may be embodied in other specific
forms without deviating from the spirit thereof. The present invention is
therefore to be limited only by the scopes of the following appended
claims.
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