Title of Invention

A SAFETY SYSTEM

Abstract A safety system for use with a machine having a moving tool arranged to move through a known path of movement. The safety system is arranged to detect the presence of an obstruction in a region (20) around a portion of said path deemed to be hazardous. The safety system is characterized by comprising a light emitting means (16), a light receiving means (18) and a processing and control means. The light emitting means (16) is arranged to emit light generally parallel to the path of movement of the tool such that the region (20) is illuminated. The light receiving means (18) is arranged to receive light from the light emitting means (16) which has passed through the region (20). The processing and control means is arranged to receive information from the light receiving means (18) and determine whether an obstruction exists in the region (20) by the presence of one or more shadow regions cast on the light receiving means (18) by the obstruction and to control movement of the tool (12) dependent on the presence of obstructions in the region (12).
Full Text BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a safety system, in particular a system for use with
machinery having moving parts, such as press brakes, to detect the presence of an
obstruction in the path of the moving part.
FIELD OF THE INVENTION
In the past, various mechanisms have been used to prevent the operators of industrial
machinery, such as press brakes, from placing their hands beneath the moving tool
during operation. Such action by the operator obviously has the potential to cause
serious injury to the operator, given the force applied by the tool and the speed at
which it can move.
One such safety mechanism involves the use of physical guards that are placed
between the operator and the tool. The use of physical safety guards however can
obstruct the view of the operator during use and impede access to the work making it
difficult for the operator to perform their job in the most efficient manner. Also,
physical tethers have been used to keep the operator at a safe distance from the
moving tool during operation. Tethers have been employed in the form of a double
handed start switch at a safe distance from the tool to ensure that the operator does not
have a free hand to place near the tool during operation. The use of tethers however
also makes holding and manipulation of the work difficult and therefore decreases the
efficiency with which the operator can work.
Various arrangements have also been used where a number of light beams are used to
create a light curtain which bounds an area around the path of the moving tool which
is deemed to be hazardous. The light beams are projected onto detectors which are
able to sense when the beam is broken and trigger either a halt or slow down of the
movement of the tool. These arrangements of individual light beams also have
disadvantages in that the operator is kept away from the work area. It is generally
necessary also to reset the position of the light curtains between production batches.
Also, they define only one area around the tool which, if obstructed by any object,
whether part of the operator or not, will deactivate the machinery. Further the use of
individual light beams also results in small gaps in the light curtain, into which small
objects such as fingers can be placed without triggering deactivation of the machine.
A further method of providing safety protection is with the use of one or more light
beams projected along the leading edge of the tool. The light beams are arranged to
move with the tool and slow or stop the tool if an obstruction breaks the beam. In
such arrangements the beam must be deactivated as the tool approaches the work and
the light beam must be set at a sufficient distance from the tool to stop the tool in
time. The minimum permissable distance of the beam from the tool is therefore
dependent on the maximum speed of movement of the tool. In some cases, multiple
light beams may be used at varying distances from the tool.
Known problems with these types of arrangements include the need to re-align the
light beams when tools are changed and the possibility that an operator may move
their hand under the tool just as the beams are deactivated. Also, as with light
curtains, all parts of the work, such as bent up stands when bending a box in a press
brake, must be kept clear of the beams as operator confirmation is required every time
a new obstruction is encountered.
The present invention attempts to overcome at least in part some of the
aforementioned disadvantages of previous safety systems used for detecting the
presence of obstructions in hazardous areas around machines having moving parts.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention there is provided a safety
system for use with a machine having a moving tool arranged to move through a
known path of movement, the safety system being arranged to detect the presence of
an obstruction in a region around a portion of said path deemed to be hazardous, the
safety system is charactered by comprising:
a light emitting means arranged to emit light generally perpendicular to the path of
movement of the tool such that said region is illuminated;
a light receiving means arranged to receive light from the light emitting means which
has passed through said region; and
a processing and control means arranged to receive information from the light
receiving means and determine whether an obstruction exists in said region by the
presence of one or more shadow regions cast on the light receiving means by the
obstruction and to control movement of the tool dependent on the presence of
obstructions in said region.
DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to
the accompanying drawings, in which:
Figure la is a view of a light emitting means and lens arrangement for illuminating a
region under the tool, in accordance with the present invention;
Figure lb is a view of an alternative embodiment of a light emitting means and lens
arrangement for illuminating the region under the tool;
Figure 2a is a view of a light receiving means and lens arrangement for receiving light
from the light transmitting means of Figure la;
Figure 2b is a view of a light receiving means and lens arrangement for receiving light
from the light transmitting means of Figure lb;
Figure 3 is a perspective view of a CCD used as the light receiving means;
Figure 4 is a perspective view of a press brake with a region around the tool edge
illuminated in accordance with the present invention;
Figure 5 is a cross sectional view of the illuminated region created by the light
emitting means showing a shadow mask used for checking purposes;
Figure 6 is a view of a shadow map 54 created by the safety system during operation
of the press brake of Figure 4.
Figure 7 is a view of an illuminated region having a stop-zone defined around the
tool; and
Figure 8 is a view of the illuminated region of Figure 7 as the tool approaches the
anvil.
DESCRIPTION OF THE INVENTION
Referring to the Figures, there is shown a safety system for use with machinery
having moving parts to detect the presence of an obstruction in the path of the moving
part. In the embodiment shown, the safety system is employed on a press brake
comprising a tool 12 arranged to move relative to an anvil 14 and to strike work
placed on the anvil 14. The safety system includes a light emitting means 16 and a
light receiving means 18. The light emitting means 16 is arranged to illuminate a
region 20 around a portion of the path of movement of the tool 12 in order to detect
obstructions in said region 20.
Figure la shows an arrangement in which a laser diode 22 is used to create a large
area parallel light beam 24. In the arrangement shown in Figure la, the laser diode 22
is used to illuminate a spherical ball 25. The spherical ball 25 concentrates the laser
beam onto a point 26. The point source of light may be further refined by passing it
through a pin hole (not shown), Past the point 26, the laser light beam is corrected by
the use of a transmitting end concave lens 30 and a first transmitting end convex lens
32. The light beam is then formed into the parallel beam 24 by a second transmitting
end convex lens 34. It will be appreciated that while an arrangement using the
spherical ball 24, transmitting end concave lens 30 and first and second transmitting
end convex lenses 32 and 34 has been used to create the parallel light beam 24 in this
embodiment, other arrangements would be possible to generate the parallel light beam
24.
Figure lb shows an alternative arrangement in which the laser diode 22 is used to
create the large area parallel light beam 24. In this arrangement, a transmitting end
aspheric or achromatic lens 35 is used in place of the transmitting end concave lens 30
and first and second transmitting end convex lenses 32 and 34. Alternatively, two
transmitting end convex lenses may be used in place of the aspheric or achromatic
lens 35. Also a transmitting end minor 37 is used to allow an increase in focal length
without significantly increasing the length of the light emitting means arrangement
which allows the two series convex lenses to be used with no further correction
required.
Figure 2a shows an arrangement used for focussing the parallel light beam 24 onto the
light receiving means 18. The arrangement of lenses used is the reverse of that shown
in Figure la, in that the light beam 24 is passed through first and second receiving end
convex lenses 36 and 38 and a receiving end concave lens 40 in order to focus the
beam 24 onto the light receiving means 18.
Figure 2b shows an alternative arrangement for focussing the parallel light beam 24.
The arrangement is the reverse of the transmitting end, using a receiving end
achromatic or aspheric lens 39 and a receiving end mirror 41. Alternatively, two
convex receiving lenses may be used in place of the achromatic or aspheric lens 39.
The light receiving means 18 comprises an aperture 42 in a screen 44 and an image
detection device 46. The image detection device could be a charge coupled device
(CCD) or a projection screen with a camera to observe the projected image. The
receiving size is preferably smaller than the image detection device 46. In this way,
the portion of the image on the image detection device 46 can be used to determine
misalignment. Also a high shutter speed may be used to give a strobe effect. Images
and in particular the position of obstructions between the strobed images may be
determined by interpolation.
As shown in Figure 4, the light emitting means 16 is mounted at one end of the tool
12 of the press brake such that the parallel light beam 24 illuminates a region 20
around the path of movement of the tool 12 which includes the forward edge 48 of the
tool 12. The light receiving means 18 is mounted at the opposite end of the tool 12 to
receive the light beam 24. If an obstruction 50, such as the hand of the operator, enters
the region 20, a corresponding shadow 52 will be cast on the image detection device
46. The light emitting means 16 and light receiving means 18 are mounted to be
stationary relative to the tool 12.
The safety system also includes a processing and control means (not shown)
connected such that the processing and control means receives information from the
light receiving means 18 and processes this information and controls operation of the
press brake. The processing and control means may be in the form of a software
program residing on a digital signal processor, a computer or embedded into a
microcomputer which receives input from the output of the light receiving means 18.
The processing and control means captures the images received by the image
detection device 46 and processes the images to search for any unknown shadows.
The processing and control means stores in memory the image received by the image
detection device 46 in which no obstructions are present In the case where the light
emitting means 16 and light receiving means 18 are mounted stationary relative to the
tool 12, the image includes the forward edge of the tool 12. The processing and
control means compares the current image received by the image detection device 46
with this stored image to determine the presence of any shadows on the image
detection device 46 created by obstructions in the region 20. If any new obstructions
are detected, the processing and control means may either stop or slow the movement
of the tool l2.
In one method of controlling the movement of the tool 12 where an obstruction is
detected, the processing and control means determines the vertical distance between
the tool 12 and the obstruction and allows continued movement of the tool 12 while
the distance determined is greater than the distance required to stop the tool 12. The
processing and control means may also determine the thickness of the shadow cast by
the obstruction and allow continued movement of the tool 12 if the.thickness is
determined to be such that the obstruction could not be part of the operator's body. If
the tool 12 is to be stopped, the operator may confirm that continued operation of the
tool 12 is safe by an input means, such as a button, arranged to provide a signal to the
processing and control means.
The processing and control means may also create a total picture made up of the
image information received by the light receiving means 18 as the tool 12 moves
through its path of movement. The picture is created and stored in a memory means
by the processing and control means. This total picture will be referred to as a
shadow map. A shadow map 54 is shown in Figure 6 in which no shadows other than
those of the tool 12 and anvil 14 are detected. Such a shadow map 54 would be
created on a first pass of the tool.
The processing and control means can store in the memory means a number of known
safe shadow maps. The known safe shadow maps being shadow maps 54 where no
obstruction is detected which would require stopping or slowing of the press brake.
For example, the shadow map 54 in which the only shadow cast is that of the forward
edge of the tool 12 and the anvil would be a known safe shadow map 54.
In use, if an obstruction is placed in the path of the light beam 24, a shadow 52 is cast
on the image detection device 46. The processing means recognises the presence of an
unknown shadowed area in the shadow map 54 and halts or slows the movement of
the tool until either the shadow disappears by removal of the obstruction or the
operator confirms that operation of the press brake is safe to continue by operation of
the input means. Further the processing and control means could allow the tool 12 to
descend to a point adjacent the obstruction before stopping in order to assist the
operator to identify the location of the obstruction which has triggered the
deactivation of the press brake.
In the case where the obstruction detected by the safety system is one deemed to be
safe to continue operation, such as the edge of work which has previously been bent
up, the processing and control means stores that shadow map as a known safe shadow
map. Therefore, when this work is repeated, the processing and control means
automatically recognises the obstruction as being non-hazardous and allows continued
operation of the press brake.
The processing and control means may still however determine that an obstruction is
hazardous even if the obstruction has previously been detected and the operator has
confirmed it is safe to proceed. For example, if the processing and control means
detects a known shadow adjacent an edge of the illuminated region, and the known
shadow is determined to be of a sufficient size that it could be hiding a hazardous
obstruction, then the processing and control means may need to slow or stop
movement of the tool 12, or stop the blade at a suitable distance from the material.
To maintain safety requirements, the known safe shadow maps are discarded by the
processing and control means if they are not re-detected within a specified time
period.
In order to create the shadow maps 54 during operation, a tool position detector is
required to provide information to the processing and control means as to the position
of the tool 12 from the anvil 14 in order to create the full shadow map. An
alternative embodiment, as shown in Figures 7 and 8, of the safety system may be
provided in which a tool position detector is not used to detect the possible position of
the tool 12. In this embodiment, the processing and control means is arranged to
detect the presence of a V-shaped illuminated region 60, being the region defined
between the 'V of the anvil 14 and the work.
Also in this embodiment the processing and control means is arranged to define a
stop-zone 62, being an area of the illuminated region around the edge of the tool 12.
If the stop-zone 62 is obstructed when the V-shaped illuminated region 60 is
determined to be an unsafe distance from the point of obstruction, as shown in Figure
8, then the processing and control means causes the tool 12 to be stopped a safe
distance from the material. Operator confirmation is then required to proceed.
The detection of the presence of the anvil 14 may also be through other means. This
may be necessary if, for example, parts of the work obstruct the V-shaped illuminated
region 60, preventing accurate detection. Preferably a combination of these
techniques would be used.
The processing and control means also includes means to reduce the possibility of
false triggering. The processing and control means provides for shadow expansion,
whereby the shadow is expanded by a sufficient number of pixels to allow for
vibration or other inaccuracies. Also, shadows created while the tool 12 is stopping
are ignored due to the possibility of the high deceleration deflecting the light emitting
and receiving means 16 and 18. Further, the processing and control means ignores the
action of the press brake back gauge. The shape and possible positions of the back
gauge are pre-configured into the safety system when the safety system is first
commissioned.
The safety system would preferably be provided with a shadow mask 56, as shown in
Figure 5, placed in front of the light emitting means 16 used for checking that the
safety system is receiving the light beam 24 correctly. The shadow mask 56
comprises a shape known to the processing and control means, such as a cross 58. The
processing and control means then checks for the presence of the shadow mask 56
shape and triggers deactivation of the press brake should the shadow mask 56 not be
detected. Further, shadow masks may be provided at both the light emitting means 16
end and light receiving means 18 end. By ensuring alignment of the shadow masks at
each end, alignment of the system can be confirmed or a slight misalignment
compensated for.
It may be required due to some safety standards for the light emitting device to be
pulsed such that the light emitting means 16 is turned off or dimmed between each
frame being acquired. The light emitting means 16 would preferably be turned on for
the minimum time period required to activate the image detection device, thus
assisting the processing and control means via a strobing effect. The processing and
control means can use the off or dimmed period to ensure that ambient light does not
falsely illuminate the light receiving means 18.
The safety system may be provided with an output device, such as a screen or
computer monitor which displays the images cast on the image detection device 46
and therefore assists the operator in identifying the obstructions detected.
The safety system could also include the use of a quartz deflection device in front of
the light transmitting means 16 to correct for vibration and could also employ off-axis
parabolic reflectors within the light emitting and receiving means 16 and 18
arrangements to remove the need for lensing and increase the sensing area. Also, the
processing and control means could analyse the bending of the work in order to
reduce the risk of finger entrapment between the work and the tool 12. The
movement of shadows that are inconsistent with bending material may also be used to
determine an unsafe state.
Also the safety system may include vernier adjustments for the direction of the light
emitting and/or receiving means 16 and 18 and either adjust the direction
automatically or show lights on the device to indicate in which direction the device is
out of alignment.
Modifications and variations as would be apparent to a skilled addressee are deemed
to be within the scope of the present invention. For example, while the light beam 24
is described as a large area parallel light beam, it would be possible to use a matrix of
focussed light emitting means and a matrix of discrete sensors. A sweet spot pin
photodiode could be used with a matrix of light emitting means being pulsed so as to
produce a picture. Alternatively, a scanning parallel ray laser could be used in place
of the matrix of light emitting means. In this method, the lights in the matrix could be
pulsed one after the other in a scanning arrangement or the laser scanned so that the
pin photodiode turns on when a parallel ray of light is received from the matrix and
stays off when an obstruction casts a shadow. Further, a row of sweet spot pin
photodiodes could be used and places behind an optical slit. Many wide beam lasers
could then be flashed sequentially so as to produce a picture in a similar fashion to
that described above.
Also, the light emitting means 16 and light receiving means 18 could be mounted to
be stationary with respect to the anvil 14 rather than the tool 12 and alternative
devices could be used for the components of the light emitting means 16, light
receiving means 18 and associated optical equipment. For example, an off-axis
parabolic reflector could be used as a replacement for the mirror and lens
arrangements of the embodiment shown in Figures lb and 2b.
WE CLAIM :
1. A safety system for use with a machine having a moving part arranged to move through a
known path of movement, the safety system characterised by comprising:
at least one light emitting means arranged to emit light, the axis of the emitted light being
aligned to illuminate a region including at least a portion of said path of movement;
at least one light receiving means arranged to receive light from one or more of the light
emitting means which has passed through said region; and
a processing and control means arranged to receive information from the light receiving
means and thereby recognise the presence of one or more shadowed regions within the
vertical and horizontal extents of said illuminated region on the light receiving means cast by
obstructions in the region;
wherein the illumination of the region is such that the processing and control means has
sufficient information to determine the boundaries of the or each shadowed region and
control movement of the part dependent on said information.
2. A safety system in accordance with claim 1, characterised in that the processing and
control means either slows or stops the movement of the part if the processing and control
means determines the presence of an obstruction in a predetermined or calculated area of the
region.
3. A safety system in accordance with claim 1 or 2, characterised in that the processing and
control means calculates the positions of the obstructions relative to the part or relative to
each other and slows or stops the part dependent on the relative positions.
4. A safety system in accordance with any one of claims 1 to 3, characterised in that the
processing and control means calculates the speeds of movement of the obstructions relative
to the part or relative to each other and slows or stops the part dependent on the relative
speeds.
5. A safety system in accordance with any one of claims 1 to 4, characterised in that the
region is large with respect to the size of a leading edge of the part and is entirely illuminated
by a single parallel beam of light.
6. A safety system in accordance with any one of claims 1 to 4, characterised in that the
region is large with respect to the size of a leading edge of the part and is illuminated by an
array of individual light beams.
7. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means is provided with an aperature to reject received light that is not
parallel to the axis of the emitted light.
8. A safety system in accordance with any one of claims 2 to 7, characterised in that an input
means is provided such that when the processing and control means slows or stops the
movement of the part, actuation of the input means by the operator informs the processing
and control means that continued movement of the part is safe and the processing and control
means resumes movement of the part.
9. A safety system in accordance with claim 8, characterised in that when the processing and
control means is informed that continued movement is safe, the processing and control means
stores in a memory means one or more maps made up of image information received by the
light receiving means as the part moves through the path of movement.
10. A safety system in accordance with claim 9, characterised in that the processing and
control means compares the current image received by the light receiving means to the maps
stored in the memory means and allows continued operation of the part if sufficiently similar.
11. A safety system in accordance with claim 9 or 10, characterised in that the processing
and control means compares the current image map being created as the part moves through
the path of movement to the maps stored in the memory means and allows continued
operation of the part if sufficiently similar.
12. A safety system in accordance with any one of the preceding claims, characterised in that
a part position detector is provided to detect the position of the part relative to the machine,
the part position detector being arranged to provide information regarding the part position to
the processing and control means.
13. A safety system in accordance with any one of the preceding claims, wherein the
processing and control means is arranged to determine the vertical distance between a
forward edge of the part and an obstruction casting a shadow on the light receiving means
and allows continued movement of the part if the distance determined is greater than a
predetermined distance required to safely stop the part.
14. A safety system in accordance with any one of the preceding claims, characterised in that
the processing and control means is arranged to determine the thickness of an obstruction
casting a shadow on the light receiving means and allow continued movement of the part
should the thickness be less than a predetermined value, the predetermined value being a
value determined to be small enough that the obstruction could not be a part of the operator's
body.
15. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means provides image information to the processing and control means
and utilises a high shutter speed to give a strobe effect.
16. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means provides image information to the processing and control means
and the light emitting means is flashed to create strobescopic images of the obstruction.
17. A safety system in accordance with claim 15 or 16, characterised in that the processing
and control means uses sampled images to determine the positions of at least parts of objects
at specific points in time .
18. A safety system in accordance with any one of claims 15 to 17, characterised in that the
processing and control means uses interpolation and determined positions of at least parts of
objects to estimate the positions of at least parts of said objects at other points in time .
19. A safety system in accordance with any one of claims 15 to 18, characterised in that said
flashing of the light emitting means is alternation between an on state in which the light
emitting means emits light and a dim state in which the intensity of the light emitted by the
light emitting means is reduced relative to the on state.
20. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means includes a charge coupled device.
21. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means comprises a projection screen and image information is detected by
a camera arranged to observe the image on the projection screen.
22. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means and the light emitting means are mounted to be stationary relative
to the part.
23. A safety system in accordance with any one of claims 1 to 21, characterised in that the
light receiving means and the light emitting means are mounted stationary relative to the
machine having the moving part.
24. A safety system in accordance with any one of the preceding claims, characterised in that
one or more shadow mask is provided and the processing and control means is arranged to
recognise the shadow created by the shadow mask on the light receiving means and use this
information to determine that the light receiving means is functioning correctly.
25. A safety system in accordance with claim 24, characterised in that the processing and
control means is arranged to recognise the shadow created by the shadow mask on the light
emitting means and use this information to determine if the safety system is in correct
alignment.
26. A safety device in accordance with claim 1, characterised in that the receiving size is
smaller than the image detection device and the position of the image on the image detection
device is used to determine misalignment
27. A safety system in accordance with claim 24, 25 or 26, characterised in that a first
shadow mask is provided and the processing and control means is arranged to detect
alignment of the system and thereby compensate for misalignments .
28. A safety system in accordance with any one of the preceding claims, characterised in that
a display device is provided to display the images received by the light receiving means.
29. A safety system in accordance with any one of the preceding claims, characterised in
that the light emitting means includes one or mores lasers as a light source.
30. A safety system in accordance with any one of the preceding claims, characterised in
that the light emitting means includes one or mores laser diodes as a light source.
31. A safety system in accordance with any one of the preceding claims, characterised in that
the light emitting means includes a transmitting end lens arrangement including one or more
transmitting end lenses such that light is directed by the transmitting end lens arrangement
through the region.
32. A safety system in accordance with claim 31, characterised in that the transmitting end
lens arrangement includes one or more concave lenses to expand the light beam.
33. A safety system in accordance with claim 31 or 32. characterised in that the transmitting
end lens arrangement includes a transmitting end spherical ball to focus the light.
34. A safety system in accordance with any one of claims 31 to 33, characterised in that the
light is focussed through a pinhole.
35. A safety system in accordance with any one of claims 31 to 34, characterised in that the
transmitting end lens arrangement includes an aspheric lens arranged to columnate the light.
36. A safety system in accordance with any one of claims 31 to 34, characterised in that the
transmitting end lens arrangement includes a lens to correct for spherical aberration such that
columnated light is directed through the region.
37. A safety system in accordance with any one of the preceding claims, characterised in that
the light emitting means includes a transmitting end reflector, the axis of the emitted light
being transmitted off axis relative to the light passing through the region.
38. A safety system in accordance with claim 37, characterised in that the reflector is an
off-axis parabolic reflector.
39. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means includes a receiving end lens arrangement such that light passing
through the region is focussed by the receiving end lens arrangement.
40. A safety system in accordance with claim 39, characterised in that the receiving end lens
arrangement includes a lens to correct for spherical aberration.
41. A safety system in accordance with claim 39 or 40, characterised in the focussed light
from the receiving end lens arrangement passes through one or more apertures.
42. A safety system in accordance with any one of claims 39 to 41, characterised in that the
receiving end lens arrangement includes an aspheric lens.
43. A safety system in accordance with any one of the preceding claims, characterised in that
the light receiving means includes a receiving end reflector, the receiving end reflector
arranged to reflect light which has passed through the region toward the or each light
receiving means.
44. A safety system in accordance with claim 43, characterised in that the reflector is an off-
axis parabolic reflector.
45. A safety system in accordance with any one of the preceding claims, characterised in that
the machine is a bending machine and the moving part is a too! of the machine.
46. A safety system in accordance with any one of claims 1 to 44, characterised in that the
machine is a bending machine and the moving part is an anvil of the machine.
47. A safety system in accordance with claim 45 or 46, characterised in that the moving part
is arranged to bend material and the processing and control means controls movement of the
tool during bending.
48. A safety system in accordance with claim 47, characterised in that the movement of the
part during bending is slowed or stopped if the image received by the light receiving means is
inconsistent with pre-stored or calculated images of material being bent in the same manner.
49. A safety system in accordance with any one of the preceding claims, characterised in that
the part is a tool, the tool is arranged to bend material and the processing and control means
controls movement of the tool during bending.
50. A safety system for use with a machine having a moving part arranged to move through a
known path of movement, the safety system comprising:
light emitting means for emitting light so as to illuminate a region including at least a
portion of said path;
fight receiving means for receiving the emitted light; and
a processing and control means for receiving image information from the light receiving
means and recognising the presence of a shadowed region within the vertical and
horizontal extents of said illuminated region on the light receiving means cast by an
obstruction in the region, determining a boundary of the shadowed region, and
controlling movement of the part responsive to the image information.
51. A safety system for use with a machine having a moving part arranged to move through a
known path of movement, the safety system comprising;
at least one light source positioned to emit light so as to illuminate a region including at
least a portion of said path;
at least one light detector positioned to receive a portion of the emitted light which has
passed through said region; and
a processor, coupled to the light detector to receive image information from the light
detector and programmed to recognise the presence of at least one shadowed region
within the vertical and horizontal extents of said illuminated region on the light
receiving means cast by at least one obstruction in the region, determine at least one
boundary of the at least one shadowed region, and control movement of the part.
52. A machine comprising:
an anvil;
a work item on the anvil;
a moving part arranged to move through a known path of movement toward the work
item to strike the work item;
at least one light source positioned to emit light so as to illuminate a region including at
least a portion of said path;
at least one light detector positioned to receive a portion of the emitted light which has
passed through said region; and
a processor, coupled to the light detector to receive image information from the light
detector and programmed to recognise the presence of at least one shadowed region
within the vertical and horizontal extents of said illuminated region on the light
receiving means cast by at least one obstruction in the region, determine at least one
boundary of the at least one shadowed region, and control movement of the part.
53. A method for operating a machine, the machine having a moving part, the method
comprising comprising:
moving the moving part along a known path of movement;
emitting light to illuminate a region including at least a portion of said path;
receiving a portion of the light which has passed through said region;
recognising the presence of a shadow within the vertical and horizontal extents of said
illuminated region cast by an obstruction in the region;
determining a boundary of the shadow; and
controlling movement of the part responsive to a property of the shadow.
54. The method of claim 53 wherein:
the controlling comprises at least one of slowing, stopping, and reversing the movement
responsive to the presence of the obstruction; and
the movement is toward a work to strike the work.
55. A method for operating a machine, the machine having a moving part arranged to
move through a known path of movement, the method characterized by comprising:
at least one light emitting means arranged to emit light, the axis of the emitted light being
aligned to illuminate a region including at least a portion of said path of movement;
at least one light receiving means arranged to receive light from one or more of the light
emitting means which has passed through said region: and
a processing and control means arranged to receive information from the light receiving
means and thereby recognize the presence ot one or more shadowed regions within the
vertical and horizontal extents of said illuminated region on the light receiving means cast by
obstructions in the region;
wherein the processing and control means processes said information received from the
region and controls the part dependent on said processed information.
56: A system according to claim 55, characterized in that the processing and control means
saves information received from the region and controls the part dependent on said saved
information.
57: A system according to any one of claim 55 or 56, characterized in that the processing and
control means controls the part dependent on the shapes and/or positions of the shadowed
regions.
58. A system according to any one of claims 55 to 57, characterized in that the machine is
used for bending material and the processing and control means analyses information from
the region during bending and controls the part dependent on said analysis.
59. A system according to any one of claims 55 to 58, characterized in that light emitting or
receiving means includes a reflector, the axis of the emitted light or received light being
transmitted off axis or received off axis relative to the light passing through the region.

A safety system for use with a machine having a moving tool arranged to move through a
known path of movement. The safety system is arranged to detect the presence of an
obstruction in a region (20) around a portion of said path deemed to be hazardous. The
safety system is characterized by comprising a light emitting means (16), a light receiving
means (18) and a processing and control means. The light emitting means (16) is
arranged to emit light generally parallel to the path of movement of the tool such that the
region (20) is illuminated. The light receiving means (18) is arranged to receive light
from the light emitting means (16) which has passed through the region (20). The
processing and control means is arranged to receive information from the light receiving
means (18) and determine whether an obstruction exists in the region (20) by the
presence of one or more shadow regions cast on the light receiving means (18) by the
obstruction and to control movement of the tool (12) dependent on the presence of
obstructions in the region (12).

Documents:

1989-KOLNP-2004- AMANDED CLAIMS.pdf

1989-KOLNP-2004-(14-03-2012)-FORM-27.pdf

1989-kolnp-2004-abstract.pdf

1989-kolnp-2004-claims.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.1.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.2.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.3.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.4.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.6.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.7.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.8.pdf

1989-KOLNP-2004-CORRESPONDENCE 1.9.pdf

1989-KOLNP-2004-CORRESPONDENCE.1.5.pdf

1989-kolnp-2004-correspondence.pdf

1989-kolnp-2004-correspondence1.10.pdf

1989-KOLNP-2004-DESCRIPTION (COMPLETE) 1.1.pdf

1989-kolnp-2004-description (complete).pdf

1989-kolnp-2004-drawings.pdf

1989-kolnp-2004-examination report.pdf

1989-KOLNP-2004-FORM 1 1.1.pdf

1989-kolnp-2004-form 1.pdf

1989-kolnp-2004-form 13.1.pdf

1989-kolnp-2004-form 13.pdf

1989-kolnp-2004-form 18.1.pdf

1989-kolnp-2004-form 18.pdf

1989-KOLNP-2004-FORM 2 1.1.pdf

1989-kolnp-2004-form 2.pdf

1989-KOLNP-2004-FORM 3 1.3.pdf

1989-KOLNP-2004-FORM 3 1.4.pdf

1989-KOLNP-2004-FORM 3.1.1.pdf

1989-KOLNP-2004-FORM 3.1.2.pdf

1989-kolnp-2004-form 3.1.pdf

1989-kolnp-2004-form 3.pdf

1989-kolnp-2004-form 5.1.pdf

1989-kolnp-2004-form 5.pdf

1989-kolnp-2004-granted-abstract.pdf

1989-kolnp-2004-granted-claims.pdf

1989-kolnp-2004-granted-description (complete).pdf

1989-kolnp-2004-granted-drawings.pdf

1989-kolnp-2004-granted-form 1.pdf

1989-kolnp-2004-granted-form 2.pdf

1989-kolnp-2004-granted-letter patent.pdf

1989-kolnp-2004-granted-specification.pdf

1989-kolnp-2004-international preliminary examination report.pdf

1989-kolnp-2004-international publication.pdf

1989-kolnp-2004-international search report.pdf

1989-KOLNP-2004-OTHERS 1.1.pdf

1989-KOLNP-2004-OTHERS 1.2.pdf

1989-KOLNP-2004-OTHERS 1.3.pdf

1989-KOLNP-2004-OTHERS DOCUMENTS.pdf

1989-KOLNP-2004-OTHERS PCT FORM.pdf

1989-KOLNP-2004-OTHERS.pdf

1989-KOLNP-2004-PA.pdf

1989-kolnp-2004-pa1.1.pdf

1989-KOLNP-2004-PCT PRIORITY DOCUMENT NOTIFICATION.pdf

1989-kolnp-2004-reply to examination report.pdf

1989-kolnp-2004-reply to examination report1.1.pdf

1989-kolnp-2004-specification.pdf


Patent Number 247271
Indian Patent Application Number 1989/KOLNP/2004
PG Journal Number 13/2011
Publication Date 01-Apr-2011
Grant Date 30-Mar-2011
Date of Filing 27-Dec-2004
Name of Patentee DAVIES KEVIN STEPHEN
Applicant Address 18 TECOMA STREET, DUNCRAIG, PERTH, WESTERN AUSTRALIA 6023
Inventors:
# Inventor's Name Inventor's Address
1 DAVIES KEVIN STEPHEN 18 TECOMA STREET, DUNCRAIG, PERTH, WESTERN AUSTRALIA 6023
PCT International Classification Number F16P3/14;B30B15/10
PCT International Application Number PCT/AU03/00707
PCT International Filing date 2003-06-10
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2002951351 2002-07-10 Australia
2 PS 2878 2002-06-11 Australia
3 2002950078 2002-07-10 Australia