AU2006200946A1 - Safety system method for a cutting device - Google Patents

Description

06/03/2006 12:31 0395612708 THAVA PAGE 12/12

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Co Cl Safety System. &Method For A Cutting Device

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The present invention relates to a safety system for a cutting apparatus, and relates particularly, but not exclusively, to band saws used by butchers for cutting meat.

0 0 N Backegound of IovetiQn 0O CI In the prior art, butchers use a mechanical band saw to cut meat. A band saw is in the form of a continuous band of saw-blade. The band saw-blade can move continuously around a circuit. Part of that circuit passes through a platform. The butcher places a lump of meat on the platform, and pushes the meat into the moving band saw in order to cut the meat.

Typically, band saws are used for cutting very large pieces of meat. The butcher has to exert a forwards-force on the meat, in order to push the meat into the band saw.

Because of the butcher's hands are pushing the meat into the moving blade, the butcher must remain vigilant to avoid his hand coming too close to the moving blade. Otherwise, the butcher's hand can be severely cut by the band saw.

Butchers can often use band saws for many hours per day, and is difficult for a human operator to remain vigilant for 100% of the time when operating these band saws.

As in any repetitive and manual operation, it is possible that fatigue or boredom can cause the operator's mind to wander for a few seconds. An accident can occur during this momentary lapse of concentration or carelessness. Realistically, these lapses of concentration are unavoidable.

Moreover, in order to keep the meat fresh, the meat is kept at very low temperatures, typically around 1 to 3 degrees Centigrade. Hence, the butcher's hands tend to become numb with cold after handling these pieces of meat for lengthy periods of time. An unfortunate consequence is that when the butcher's inadvertently allow his COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 11/12 2

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o 5 fingers or hands to follow the meat into the moving band saw, the butcher can sometimes CA not instantly pull back his hands in pain. Instead, the numbness of his cold hand means Sthere can sometimes be a delay in realizing that his hand has been cut by the blade. Hence Sthe degree of damage from these accidents can often be very severe.

O In the state of Victoria in Australia, it is estimated that there are typically two accidents per month involving butchers inadvertently having their fingers or fingertips cut O by the band saws. In extreme cases, there are reports of butchers losing their arms.

Similar problems are found when band saws are used in other areas, for example, o by carpenters, although the exacerbating factor of the band saw operator having frozen hands tends not to be present in these other areas.

An object of the present invention is to overcome or at least ameliorate one or C' more the above problem in the prior art, or to prove an improved alternative.

Summary Sf Invention 201 According to a first aspect of the present invention, the-re is provided a cutting safety system including; temperature-sensor-safety-means adapted to monitor temperature of a region that is proximate a cutting location of a cutting means, the temperature-sensor-safety-means adapted to actuate a safety action when an object having a temperature above a predetermined level enters the region.

Preferably, the temperature-sensor-safety-means actuates the safety action when an object having human-hand-like temperature enters the region.

Preferably, the region has a perimeter that is separated by a distance from the cutting location such that when the user's hand crosses the perimeter the temperaturesensor-safety-means can actuate the safety action in sufficient time to prevent the user's hand moving into the cutting means.

Preferably, the distance is greater than a human hand size.

Preferably, the region is a circle that has said distance as its radius and wherein the cutting location is positioned generally at the centre of the circle.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 10/12 3 The cutting means may be a band saw of a cutting apparatus, and the temperature- CN sensor-safety-means may include a non-contact temperature measurement apparatus c adapted to monitor the temperature of the region remotely without physical contact with Sthe object that is cut by the band saw.

O The meat-cutting apparatus may include a cutting-platform on which the object is cut, and wherein the temperature-sensor-safety-means is positioned above the platform so as to monitor from above the region below.

The safety action may include activating a warning light.

o The safety action may include an audible warning sound.

C The safety action may include stopping operation of the cutting means.

O 15 Within the region, there may be one or more sub-regions, and the temperature- Ci sensor-safety-means may also be adapted to actuate a further safety action when the object enters each of the one or more sub-regions.

Preferably, the further safety action involves stopping movement of the cutting means.

Preferably, the system includes region-identification-means that allows a user to visually identify the location of said region Preferably, the region-identification-means includes lighting means for shining a light on at least a part or whole of the region.

Preferably, the lighting means includes a laser light generator adapted to shine one more laser beams onto a part of the region.

Preferably, the lighting means shines light onto at least an edge margin of the region.

The predetermined level may be preset at above 3 degrees Centigrade.

Preferably, the system includes adjustment means for adjusting the predetermined temperature.

According to a second aspect of the present invention, there is provided a meat cutting apparatus having a safety system, the apparatus including meat cutting means having a cutting location where meat is cut; and wherein the safety system is as summarized above.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 09/12 4

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CN According to a third aspect of the present invention, there is provided a safety cmethod of protecting a band saw user's hands, including: providing a band saw apparatus with a safety system which includes temperature- O sensor-safety-means adapted to monitor temperature of a region that is proximate a cutting location of a cutting means, IO using the temperature-sensor-safety-means to actuate a safety action when an object having a temperature proximate the user's hand temperature range enters the Sregion.

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o is According to a fourth aspect of the present invention, there is provided a 0 Ci temperature-sensor-safety means adapted to monitor temperature of a region that is proximate a meat-cutting location of a meat-cutting apparatus, the temperature-sensorsafety-means adapted to actuate a safety action when an object having human-hand-like temperature enters the region.

According to a fifth aspect of the present invention, there is provided a safety method of stopping operation of a meat-cutting apparatus that has meat cutting means with a cutting location where meat is cut, the method including: using temperature-sensor-safety-means of a safety system to monitor temperature of a region that is proximate the cutting location; and using the temperature-sesor-safety-means to actuate a safety action when an object having human-hand-like temperature enters the region.

Drawings In order that the invention might be more fully understood, embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a front view of a conventional meat cutting apparatus provided with an embodiment of cutting safety system; COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 08/12 \o S 5 Figure 2 is a side view of the meat cutting apparatus of Figure 1 that is provided CA with the embodiment of cutting safety system; C Figure 3A is a diagrammatic representation, seen from above, of a user's hand pushing a piece of meat towards a band saw blade, showing the user's hand outside the o safety zone; Figure 3B is a diagrammatic representation, seen from above, of the user's hand NO pushing the piece of meat into a band saw blade, with the user's hand having moved into the safety zone; o Figure 4 shows another embodiment in which the distance from the saw blade to C the perimeter of the safety zone is approximately the size of a typical human hand; S 15 Figure 5 shows a further embodiment in which the safety zone is provided with Ci several layers of sub-zones; Figure 6 shows a perspective view of a temperature monitoring apparatus that is part of the embodiment of the cutting safety system; and Figure 7 is a block flow diagram of an exemplary embodiment of an electrical control circuit used to control the embodiment of the cutting safety system.

Description of Embodiments Referring to the accompanying drawings, Figure 1 shows an embodiment of a meat cutting safety system which is used with a known, prior art meat-cutting apparatus 100.

The meat-cutting apparatus 100 has a cutting-means in the form of a band sawblade 110.

The apparatus 100 has a platform 120 on which the meat is placed for it to be cut.

Referring to Figures 3A and 3B, the band saw-blade 110, in use, moves continuously around a circuit. A piece of meat 130 is placed on the platform 120. The user's hand 140 guides the meat 130 towards the blade 110.

Figure 3A shows the meat before it contacts the blade 110, while Figure 3B shows the meat being cut by the blade 110.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 07/12 6

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o 5 Warning Syt t The meat cutting safety system, of the embodiment, is designed to warn the user, for instance, a butcher, if his hand comes too close to the cutting edge of the saw-blade o 110.

Io To achieve this warning capability, in Figures 1 and 2, the meat cutting safety \NO system has a temperature-sensorsaty-means which includes a temperature monitoring apparatus 200.

0 0 NC Overview of the System

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Ci As an overview, the temperature monitoring apparatus 200 monitors the temperature of a safety region 300 on the platform 120. The safety region 300 is near the location where the blade 110 cuts the meat.

The theory is that refrigerated meat is cold. In contrast, the user's hand will be significantly warmer than the cold, refiigerated meat. Therefore, the monitoring apparatus 200 monitors the temperature of any objects within the region. If it detects any object that has the temperature above a predetermined level, then the monitoring apparatus 200 takes this to mean that a user's hand is located within the region, and thus actuates a safety action, Experiments may be conducted to see how cold a human hand can get under the conditions of the particular situation.

Predetermined Temperareg In the present embodiment, the apparatus 200 is designed to detect when a human hand enters the region. Hence, the predetermined temperature level is set for around the level of human-hand-like temperature.

Even when the user's hands are constantly handling cold meat for many hours, there is still a finite temperature difference between the cold meat and the cold human hand, that is sufficient for the monitoring apparatus 200 to distinguish between the two.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 06/12 7 \o Normally, refrigerated meat is kept around 1 to 3 degrees Centigrade, hence, the C predetermined temperature could be set anywhere above 3 degrees, for example, at Saround 5 degrees Centigrade. Some experimentation may be done to select a suitable cutoff temperature for the prevailing conditions.

o The embodiment of the system monitors the region using a non-contact temperature sensor. In the embodiment, the temperature sensor is a Convir IL Series Non- VO contact temperature sensor, model JL101, manufactured by Calex Electronics Limited of 0\ Bedfordshire, England, however, and it had to be specially programmed for the inventor 0 to specifically operate in the temperature ranges needed for the present embodiment. In other embodiments, other types of non-contact temperature measurement systems or S 15 products can be used to measure temperature without contact of the safety region 300.

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1 The embodiment of the system does not interfere if the temperature in the safety region 300 is three degree Centigrade or below. However, if the temperature in the region 300 is higher than this predetermined temperature value, the system assumes that the user's hand has come critically near the saw. Thus, at that instant, the system activates a safety action to warn or protect the user, such as audio and/or visual warning signals.

Safety Region In Figure 3A, the safety region 300 has a perimeter 310.

In Figures 3A, 3B and 4, the perimeter 310 is separated from the location of the cutting blade 110 by a distance (shown, for example by the letter X in Figure The measure of this distance is what is considered a safe distance such that, when the user's hand crosses the perimeter moving at a normal speed, the temperature monitoring apparatus 200 can trigger a safety action, which leaves sufficient time to prevent the user's hand moving all the way into the blade 110.

In the embodiment of Figure 4, the distance X is greater than a human hand size.

In this embodiment, the region 300 is a circle that has the distance X being its radius. The location of the cutting blade 110 is generally at the centre of the circle.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 05/12

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\o A larger circle may be needed if the hand is moving faster, since the hand would tend to move a greater distance during the reaction time when the user is alerted or C becomes aware of the safety action of the system.

SIn other embodiments of the invention, the size of the region can be modified by Va the user during a calibration phase.

O Non-Contact Temperature Measurement SDetecting the presence of a human hand 140 in the safety region 300 is achieved n by monitoring the temperature in the region.

O 15 In contrast, competitive methods that use colour detection would have C' disadvantages. Firstly, human skin colour can vary depending on the user's ethic background. Secondly, the colour of the meat can also vary, depending on its freshness and other factors. Whereas the range of temperatures of a human hand remain fairly predictable, Non-contact temperature measurement In Figures 1 and 2, the temperature monitoring apparatus 200 is positioned high above the platform 120 where the meat is cut. Thus, the apparatus 200 functions as a noncontact temperature measurement system that is adapted to monitor the temperature remotely without physical contact with the region or objects below.

Safety Actions The safety action, that is actuated by the temperature monitoring apparatus 200, can includes a range of possible actions, including: activating a warning light; activating an audible warning sound; and/or stopping the cutting motion of the saw blade.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 04/12 9

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The safety action may be a combination of one or more of the above actions, or

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1 other actions. The safety action is sufficient to warn and/or prevent the user from being C hurt by the cutting blade.

Multiple Regions V\ In a further modified embodiment in Figure 5, the safety region 300 has one or more sub-regions within the main region.

o The temperature monitoring apparatus 200 may actuate different safety actions c when the user's hand enters each of the one or more sub-regions.

o 15 In the example of Figure 5, there are three layers, in sequence: C' a first perimeter 310; an outer region 300; a second perimeter 330; an intermediate sub-region 320; a third perimeter 350; and an inner sub-region 340.

As each layer is located closer to the cutting blade 110, the intensity or urgency of its associated safety action can increase.

For example, in the three regions of Figure when the hand crosses the first perimeter 310, the temperature monitoring apparatus 200 actuates a flashing light; when the hand crosses the second perimeter 330, the temperature monitoring apparatus 200 actuates an audible warning alarm 280; and when the hand crosses the third perimeter 350, by this stage, the user's hand is dangerously close to the cutting blade 110. Therefore, at this point, the temperature monitoring apparatus 200 actuates a signal to the meat-cutting apparatus 100 to stop the motion of the cutting blade 110.

It is preferred that audio and/or visual signals be given initially to warn the user, rather than automatically switching the machine off as the first step. Firstly, the latter would be obtrusive to the user's day to day work. Secondly, the momentum of the COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 03/12 o 5 moving band saw means that it often takes a finite period of time for the saw to come to a complete halt. Hence, it is preferred for the user to be given preliminary warnings as the c user's hands come progressively closer to the blade 110.

O Identifying The SafetyRegion \O0 In the embodiment, it is helpful for the user to be aware of the location of the safety region 310, or in the case of other embodiments, the plurality of safety regions o 300, 320, 340.

SIn the embodiment of Figure 1, the system includes region-identification-means O is that allows a user to visually identify the location of said region. This takes the form of a C1 lighting-means for shining a light on at least a part or whole of the region.

In the embodiment in Figure 6, the lighting-means includes one or more laser light generators 260 that shine one more laser beams 261 onto a part of the safety region 300 or regions.

In the embodiment, the laser generator shines light onto at least an edge margin of the region. For instance, the laser beam would shine onto part or all of the perimeter 310.

The laser-indication of the location of the safety region can shine permanently when the system is turned on. Alternatively, the laser-indication can be set to shine only on-demand by activation by the user.

The light source can use other sources, such as a conventional lamp bulb.

Temperature Monitoring Apparatus Figure 6 shows an example of an embodiment of the outer-casing 210 of the temperature monitoring apparatus 200.

The outer casing has a switch 220 that turns the power on and off The casing 210 has a green light emitting diode 230 (LED) which indicates that the power to the system is turned on by the switch 220.

The casing 210 also has a red LED light 240, which indicates when the electronic temperature sensor is monitoring the temperature of the region 300 below.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:31 0395612708 THAVA PAGE 02/12 11

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If the user wishes to receive an indication of the location of the safety region, the C user can push a button 250 that causes the two internal laser pointers 260 to shine down Sonto the region 300 below. In Figure 1 and 2, the laser pointing beams 261 aid the user to Sidentify the location of the perimeter 310 or diameter of the safety region that is being

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Smonitored.

When the user's hand comes close to the blade, the red LED 240 can be made to V.0 flash rapidly to provide a visual warning to the user.

In other embodiments, the temperature monitoring apparatus 200 can include a 0 buzzer or audible signal generator. When the hands are detected close to the blade, the buzzer can sound together with the flashing light.

o 15 It is advantageous to use all possible means to alert the user, since an accident can C happen in a matter of a few milliseconds, if the user is not shocked into stopping his hands moving too close to the blade.

The temperature monitoring apparatus 200 can include a means for adjusting the volume of the audible warning signal, to cater for different ambient noise levels.

Similarly, the temperature monitoring apparatus 200 can include a means for adjusting the light intensity of the visual warning signal, to cater for different ambient light levels.

The number and location of flashing LED signal lights can be varied.

Temperature measurement apparatus is housed inside the casing 200, and is able to monitor the region below through an aperture 270 in the underside of the casing.

A block diagram is shown in Figure 7 which includes core components of the temperature measurement apparatus used in the present embodiment.

Figure 7 shows a block diagram of an electronic control circuit 201 in Figure 8, which shows the main function of the electronic control circuit 201: 1) The electronic control circuit 201 receives electrical power from a power source 290 that supplies electrical power for operation of the control circuit; a) The power source 290 supplies electrical power at 27-volts which is required to operate the temperature probe 200.

b) The circuit 201 supplies power that is required to operate the red LEDs 230 and the audible beeper 280.

COMS ID No: SBMI-02871428 Received by IP Australia: Time 12:22 Date 2006-03-06 06/03/2006 12:25 0395612708 THAVA PAGE 03/03 12 \o c) The circuit supplies power to the laser pointers 260.

C d) The circuit 201 receives signals from the temperature monitoring t apparatus 200 that indicate the temperature of the safety region 300, and accordingly controls the rest of the apparatus in response to these signals, as described herein.

IN For safety reasons, the apparatus is grounded to earth 202.

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"Modifications C- Other modifications of the system can include a mechanism to adjust the o 15 predetermined temperature.

0 Ci In this specification, the word 'meat' is used generically, and can include different sorts of meats, and other chunky foods that need to be cut by saws.

Although the embodiments have been described with reference to using a band saw to cut meat, other embodiments of the invention can be used in areas where saws are used to cut other objects, such as wood.

In another modification, the cutting safety system can cut offpower to the cutting machine if there is no meat in the vicinity of the cutting saw, after a specified time period of say, 5 minutes. This allows conservation of electrical power when the machine is not in use.

In addition to preventing or minimizing injuries to butchers, it is possible that widespread installation of embodiments of the invention on cutting devices may minimize the likelihood of legal suits against employers for failing to take steps to protect the safety of their employees.

The safety region 300, or any sub-regions need not be circular, but can be any other shape, such as elliptical, or irregular-shaped.

The embodiments have been described, by way of example only, and modifications are possible within the scope of the invention as defined by the appended claims COMS ID No: SBMI-02871233 Received by IP Australia: Time 12:13 Date 2006-03-06

Claims (13)

1. 4. A system of claim 3 wherein the distance is greater than a human hand size. A system of claim 3 or 4 wherein the region is a circle that has said distance as its radius and wherein the cutting location is positioned generally at the centre of the circle.
2. 6. A system of any one of the preceding claims wherein the cutting means is a band saw of a cutting apparatus, and the temperature-sensor-safety-means includes a non- contact temperature measurement apparatus adapted to monitor the temperature of the region remotely without physical contact with the object that is cut by the band saw-
3. 7. A system of claim 6 wherein the meat-cutting apparatus includes a cutting- platform on which the object is cut, and wherein the temperature-sensor-safety-means is positioned above the platform so as to monitor from above the region below. COMS ID No: SBMI-02871233 Received by IP Australia: Time 12:13 Date 2006-03-06 06/03/2006 12:18 0395612708 THAVA PAGE 12/12 14 NO S8. A system of any one of the preceding claims wherein the safety action includes ^c activating a warning light.
4. 9. A system of any one of the preceding claims wherein the safety action includes an Va o audible warning sound. \O 10. A system of any one of the preceding claims wherein the safety action includes stopping operation of the cutting means. 0 0
5. 11. A system of any one of the preceding claims wherein, within the region, there is O one or more sub-regions, Ci and wherein the temperature-sensor-safety-means is also adapted to actuate a further safety action when the object enters each of the one or more sub-regions.
6. 12- A system of claim 11 wherein the further safety action involves stopping movement of the cutting means.
7. 13. A system of any one of the preceding claims wherein the system includes region- identification-means that allows a user to visually identify the location of said region.
8. 14. A system of claim 13 wherein the region-identification-means includes lighting means for shining a light on at least a part or whole of the region. A system of claim 14 wherein the lighting means includes a laser light generator adapted to shine one more laser beams onto a part of the region.
9. 16. A system of claim 14 or 15 wherein the lighting means shines light onto at least an edge margin of the region.
10. 17. A system of any one of the preceding claims wherein the predetermined level is preset at above 3 degrees Centigrade. COMS ID No: SBMI-02871137 Received by IP Australia: Time 12:08 Date 2006-03-06 05/03/2006 12:18 0395612708 THAVA PAGE 11/12 NO 0 N 18. A system of any one of the preceding claims wherein the system includes Sadjustment means for adjusting the predetermined temperature. VO 19. A meat cutting safety system substantially as hereinbefore described and 0 illustrated with reference to the accompanying drawings. A meat cutting apparatus having a safety system, the apparatus including; Smeat cutting means having a cutting location where meat is cut; and wherein the CN safety system is according to any one of claims I to 19. O C 21, A safety method of protecting a band saw user's hands, including: providing a band saw apparatus with a safety system which includes temperature- sensor-safety-means adapted to monitor temperature of a region that is proximate a cutting location of a cutting means, using the temperature-sensor-safety-means to actuate a safety action when an object having a temperature proximate the user's hand temperature range enters the region.
11. 22. A safety method of claim 21 wherein the safety system is in accordance with any one of claims 1 to 19.
12. 23. Temperature-sensor-safety means adapted to monitor temperature of a region that is proximate a meat-cutting location of a meat-cutting apparatus, the temperature-sensor- safety-means adapted to actuate a safety action when an object having human-hand-like temperature enters the region.
13. 24. Temperature-sensor-safety means which is adapted to be used in a system in accordance with any one of claims 1 to 19. COMS ID No: SBMI-02871137 Received by IP Australia: Time 12:08 Date 2006-03-06 06/03/2006 12:18 0395612708 THAVA PAGE 10/12 16 A safety method of stopping operation of a meat-cutting apparatus that has meat o cutting means with a cutting location where meat is cut, the method including: using temperature-sensor-safety-means of a safety system to monitor temperature Sof a region that is proximate the cutting location; and Susing the temperature-sensor-safety-means to actuate a safety action when an object having human-hand-like temperature enters the region. 4 26. A method of claim 25 wherein the safety system is according to any one of claims 1 to 19, (O 0 rcl COMS ID No: SBMI-02871137 Received by IP Australia: Time 12:08 Date 2006-03-06