CA2056004A1 - Electric plaster cast saw control system - Google Patents
Electric plaster cast saw control systemInfo
- Publication number
- CA2056004A1 CA2056004A1 CA 2056004 CA2056004A CA2056004A1 CA 2056004 A1 CA2056004 A1 CA 2056004A1 CA 2056004 CA2056004 CA 2056004 CA 2056004 A CA2056004 A CA 2056004A CA 2056004 A1 CA2056004 A1 CA 2056004A1
- Authority
- CA
- Canada
- Prior art keywords
- saw
- electric
- control system
- power supply
- conductive plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Landscapes
- Electrotherapy Devices (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Electric Plaster Cast Saw Control System An electric plastic cast saw control system for cutting off of plastic cast composed of an inner layer of absorbent cotton and an outer layer formed by hardened covering material including a thin conductive plate placed between the inner layer and the outer layer 50 that a relay device is triggered to cut off power supply to electric saw on the instant the saw gets contact with -the thin conductive plate and consequently stop the electric saw instantaneously, and a reset device to resume power supply to the electric saw automatically or manually after cutting off of the power source.
(Fig.4)
Electric Plaster Cast Saw Control System An electric plastic cast saw control system for cutting off of plastic cast composed of an inner layer of absorbent cotton and an outer layer formed by hardened covering material including a thin conductive plate placed between the inner layer and the outer layer 50 that a relay device is triggered to cut off power supply to electric saw on the instant the saw gets contact with -the thin conductive plate and consequently stop the electric saw instantaneously, and a reset device to resume power supply to the electric saw automatically or manually after cutting off of the power source.
(Fig.4)
Description
2 ~
~LECTRIC PLAS~ER CaST 8AW CO~ROL SYSTE~
BACKGROUND OF THE I~VENTI~N
This invention relates to a control system for electric plaster cast sawr particulc~rly a control system to stop electric plastic cast saw automatically and promptly during cutting of plaster cas-t or other covering mat~rials.
Human lim~s may be fractured under a great external force. Infant's limbs may be deformed congenitally or acquiredly. Currently, the medical treatm~nt dealiny with bone fracture or deformity always involves wrapping of medical pla~ter around the lnjured area and allowing the plaster to harden so that the limb can be healad ~uickly without external influence.
After a certain period, the plaster cast surrounding the injured limb mus-t be cut with an electric saw for removal and examination. ~he limb may have to receive other therapy or surgery if necessaLy.
In general, depth which the saw has gone into the plaster cast is judged by visual inspection, accuracy of which depends on operator's experience. Hence, skill is indispensable to avoid injury to patient's muscle.
However, even sawing is carried out carefully, patent's 2 ., ~ ~ ., , .1 skin or muscle may ba hurt accidentally, and such kind of accident occurs frequently. Therefore, patien-t is always afraid of such sawing, operator may hesitate to carry ou-t the sawing/ and consequently the opera-tion is prolonged.
Accident hurt to p~tient's skin or muscle may happen due to unexpected movement or uncontrolled shaking of limb especially when the patient is a baby or person who has lost the capacity to control his body.
Therefore, -there is an urgent need in the medical field for a controller which can stop electric saw automatically as soon as the plaster cast is cut off.
SUMMARY OF T~E INUENTIO~
The main object of the present invention is to provide a control system for electric plaster cast saw to stop electric saw automatîcally on the instance the plaster cast is cut off in order to prevent from injury to patient's skin or muscle.
Another objef-t of the present invention is to provide a control system for electric plaster cast saw which can effectively prevent from injury to patient's skin or muscle, and hence the patent's fear can be eliminated, operator's confidence for safe operation is improved, and unnecessary dispute can be avoided.
Another object of the present invent.ion is to provide a control sys-tem for elec-tric plaster cast saw which can cut of power supply an~ stop electric saw automatically on the instant the plaster cast is cut off so that cutting o~f of plater cast can be performed by any nurse or operator and then work burden of experienced nurse or surgeon can be relieved.
The electric plaster cast saw control system according to the present invention include a thin conduct:ive plate between the plaster layer and absorbent cotton layer o~
each plastic cast with an extended end o.E the thin conductive plate exposed outside -the plastic cast so that it can be connected to the control system by a conductive wire. On the instant the electric saw gets contact with the thin conductive plats, a relay is triggered to trip from its normal closed contact to normal open contact, and consequently cut o~f power supply to the electric saw instantaneously. The electric saw is hence stopped immediately to prevent ~rom injury to patient's skin or muscle. The control system has also a reset device to resume power supply to the electric saw, and a warning device to give audible or visible warning signal.
BRIEF ~ESCRIPTION OF THE DRaWI~GS
These and other objects and features of the invention 62~
will become more apparent from the following description taken in connection with the accompanying drawings wherein:
Fig. 1 is a perspective view oE th~e first em~odiment of the electric pl~ster cast saw control system according to the present invention.
Fig. 2 is a perspective view of the second embodiment of the electric pla~ter cas-t saw control system according to the present invention, in which an automatic reset device is used to replace the manual reset d~vice shown in Fi~. 1 ~ig. 3 is a sec-tional view taken along line 3-3 in Fig. 3.
Fig. 4 is a block diagram for the first embodiment of the present invention.
Fig. 5 is a block diagram for the second embodiment of the present invention.
D~TAILED DESCRIPTION OF THE P~EFERRED EMB~DIMENT
Referring to Figs. 1 and 3, each plaster cast 80 to wrap patient's fractured limb 90 has an inner layer 82 composed tearable absorbent cotton to contact with J;; ~
patient's skin, an outer layer 84 composed of a covering material which is hardened upon contact with water, normally plaster or resin for medical purpose, and a thin conductive plate lO located be-tween the inner layer and th0 outer layer. The thin conduc-tive plate lO is made of electric conductive material such as tin foil or aluminum foil which does not affect X-ray reading or diagnosis. The thin conductive plate 10 has an extended end 12 extended outside the plaster cast 80. ~he extended end 12 is designed to connect to a control system located in a power control box 20 by means o a clamp 14 and a conductive wire 16. An electric saw 86 to cut off the outer layer 84 comprises a high speed motor (not shown iII the figures) and a circular saw blade 8B fi~ed to a shaft 87 of the motor.
The shat is connected to the control system in the control box 20 with a conductive wire 18 to form a control circuit.
The electxic saw 86 is connected to a socket 22 on the control box 20 with a plug 89 for an electric power to operate the electric saw 86. The control sys-tem in the control box 20 is incorporated with a selector switch 24, a warning device 26, and a reset pedal 28. The control box 20 is connected to an external power source with a plug 30.
The warning device 26 is an electric or electronic alarm to give audible or visible warning signal. The warning device is preferably installed on the surface of the control box 20 or the Plectric saw 86 or other appropriate location so that it can be seen during the sawing process.
2~ 3 Please refer to Fig. 2 for the second embodiment of the control system for plaster cast saw accordin~ to the present invention. -ft is same with the embodiment shown in Fig~ 1 except a reset knob 32 is used instead of the reset pedal 28.
Please reer to Fig. 4 for a block diagram for the first embodiment of con'rol system for plaster cast saw according to the present invention. The control system comprises a power supply 40, a selector switch 24, a relay device 42, a warning device 26, and a reset device 46. The relay device 42 i6 composed of a relay 48, a driver 50 and a control circuit 52 to cut off power supply to the electric saw 86 ins-tantaneously as soon as the saw blade 88 gets contact with -the thin conductive plate 10. The reset device 46 is composed of the reset pedal 28 and a reset circuit 54 to restart the electric saw 86. The power supply 40 is connected to an external power source for pro~ision of electric power to the electric saw 86 directly, or to the elec~ric saw 86 through the relay device 42 by selection of its operator. If the selector switch 24 is located at the first contact A, the electric saw is started directly for continuous operation, the relay device 42, the warning device 26 and the reset device 46 do not function. If the selector switch 24 is located to the second contact B, the power source is not provided to the electric saw directly, but is connected to a common contact C for the relay 48 which is normally closed at NC so that the electric saw 85 can not be operated. The power source also provides an electric power to the cont~ol circuit 52 so that the control circuit is ready to receive signal and upon triggering of the reset device 46 by ~tepping the reset pedal 28, which causes the reset circuit 54 to trig~er the control circuit 52, start the driver 50 to drive to relay 48 to trip from the normal closed contact NC
to a normal open contact NO, and consequently the power supply 40 provides the electric saw 86 with an electric power through the common contact C and the norma:L open contact NO for operation o the electric saw 86. ~y this way, the electric saw 86 can be operated to cut o~f plaster cast. Whenever the saw blade 8B gets contact wi~h the thin conductive plate 10 after cutting off of the outer layer 84, the saw blade 88, the thin conductive plate 10, the warning device 26 and the control circuit 52 become a closed loop, the warning device 26 is activated to give a warning light or voice, the control circuit 52 cut off the driver 50 instantaneously so that -the relay 48 trips from the normal open contact NO to the normal closed contact NC
to cut off power supply to the electric saw 86, and consequently, the electric saw 86 is stopped Lmmediately.
Hence, the patent's skin or muscle can be prevented form hurting by the saw blade 88. To restart the electric saw 86, only the reset pedal 28 has to be stepped so that, as described above, the reset circuit 54 triggers the control 2 ~ 3 circuit 52 again to cause the driver 50 to drive the relay 48 to trip from the normal closed contact NC to the normal open contact NO, and start the electric saw 86 again.
The relay 48 of can be of solid state or mechanically controlled. ~he warning device shown in the figures is a warning indicator. It can be replaced by a buz2er to provide audible warning signal.
Please reer to Fig. 5, a block diagram for the second embodLment of -the present invention, the plug 30 t the power supply 40, the selector switch 24, the relay control device 42, the warning device 26, the electric saw, and the thin conductive plate 10 are same with that used in the first embodiment shown in Fig. 4, but an automatic reset device 56 is used instead of the reset device 46 in Fig. 4. The automatic reset device 5S can be an adjustable pulse generator which i5 triggered to send a pulse to the relay device 42 on the instant that the saw blade 88 gets contact with the thin conductive plate 10. Upon input of the pulse, the relay 48 trips from the normal open contact NO
to the normal closed contact ~C, and consequently the power supply to the electric saw 86 is cut off, the patent's skin or muscle can be prevented form hurting by the saw blade 88. After elapse of a delay time caused by the pulse, the relay 48, in the absence of pulse input, trips from the normal closed contact NC to the normal open contact NO, and ~ ~d ,1 s 1 consequently power supply to the e:Lectric saw 86 is resumed to continue the opera-tion. The length of the delay time can be adjusted by a variable resistor 58. The reset kno~
32 on the control box 20 can be -turned to adjust resistance of the variable resistor, and consequently adjust the length of delay time.
Procedures to operate the first embodiment of the electric plaster cast saw control ~ystem according to the present invention are described below:
(1) Connect the control box to an external power source with the plug 30.
15(2) Connect the electric saw 86 to the control ~ox 20 by inserting the plug 89 to the socket 22.
~LECTRIC PLAS~ER CaST 8AW CO~ROL SYSTE~
BACKGROUND OF THE I~VENTI~N
This invention relates to a control system for electric plaster cast sawr particulc~rly a control system to stop electric plastic cast saw automatically and promptly during cutting of plaster cas-t or other covering mat~rials.
Human lim~s may be fractured under a great external force. Infant's limbs may be deformed congenitally or acquiredly. Currently, the medical treatm~nt dealiny with bone fracture or deformity always involves wrapping of medical pla~ter around the lnjured area and allowing the plaster to harden so that the limb can be healad ~uickly without external influence.
After a certain period, the plaster cast surrounding the injured limb mus-t be cut with an electric saw for removal and examination. ~he limb may have to receive other therapy or surgery if necessaLy.
In general, depth which the saw has gone into the plaster cast is judged by visual inspection, accuracy of which depends on operator's experience. Hence, skill is indispensable to avoid injury to patient's muscle.
However, even sawing is carried out carefully, patent's 2 ., ~ ~ ., , .1 skin or muscle may ba hurt accidentally, and such kind of accident occurs frequently. Therefore, patien-t is always afraid of such sawing, operator may hesitate to carry ou-t the sawing/ and consequently the opera-tion is prolonged.
Accident hurt to p~tient's skin or muscle may happen due to unexpected movement or uncontrolled shaking of limb especially when the patient is a baby or person who has lost the capacity to control his body.
Therefore, -there is an urgent need in the medical field for a controller which can stop electric saw automatically as soon as the plaster cast is cut off.
SUMMARY OF T~E INUENTIO~
The main object of the present invention is to provide a control system for electric plaster cast saw to stop electric saw automatîcally on the instance the plaster cast is cut off in order to prevent from injury to patient's skin or muscle.
Another objef-t of the present invention is to provide a control system for electric plaster cast saw which can effectively prevent from injury to patient's skin or muscle, and hence the patent's fear can be eliminated, operator's confidence for safe operation is improved, and unnecessary dispute can be avoided.
Another object of the present invent.ion is to provide a control sys-tem for elec-tric plaster cast saw which can cut of power supply an~ stop electric saw automatically on the instant the plaster cast is cut off so that cutting o~f of plater cast can be performed by any nurse or operator and then work burden of experienced nurse or surgeon can be relieved.
The electric plaster cast saw control system according to the present invention include a thin conduct:ive plate between the plaster layer and absorbent cotton layer o~
each plastic cast with an extended end o.E the thin conductive plate exposed outside -the plastic cast so that it can be connected to the control system by a conductive wire. On the instant the electric saw gets contact with the thin conductive plats, a relay is triggered to trip from its normal closed contact to normal open contact, and consequently cut o~f power supply to the electric saw instantaneously. The electric saw is hence stopped immediately to prevent ~rom injury to patient's skin or muscle. The control system has also a reset device to resume power supply to the electric saw, and a warning device to give audible or visible warning signal.
BRIEF ~ESCRIPTION OF THE DRaWI~GS
These and other objects and features of the invention 62~
will become more apparent from the following description taken in connection with the accompanying drawings wherein:
Fig. 1 is a perspective view oE th~e first em~odiment of the electric pl~ster cast saw control system according to the present invention.
Fig. 2 is a perspective view of the second embodiment of the electric pla~ter cas-t saw control system according to the present invention, in which an automatic reset device is used to replace the manual reset d~vice shown in Fi~. 1 ~ig. 3 is a sec-tional view taken along line 3-3 in Fig. 3.
Fig. 4 is a block diagram for the first embodiment of the present invention.
Fig. 5 is a block diagram for the second embodiment of the present invention.
D~TAILED DESCRIPTION OF THE P~EFERRED EMB~DIMENT
Referring to Figs. 1 and 3, each plaster cast 80 to wrap patient's fractured limb 90 has an inner layer 82 composed tearable absorbent cotton to contact with J;; ~
patient's skin, an outer layer 84 composed of a covering material which is hardened upon contact with water, normally plaster or resin for medical purpose, and a thin conductive plate lO located be-tween the inner layer and th0 outer layer. The thin conduc-tive plate lO is made of electric conductive material such as tin foil or aluminum foil which does not affect X-ray reading or diagnosis. The thin conductive plate 10 has an extended end 12 extended outside the plaster cast 80. ~he extended end 12 is designed to connect to a control system located in a power control box 20 by means o a clamp 14 and a conductive wire 16. An electric saw 86 to cut off the outer layer 84 comprises a high speed motor (not shown iII the figures) and a circular saw blade 8B fi~ed to a shaft 87 of the motor.
The shat is connected to the control system in the control box 20 with a conductive wire 18 to form a control circuit.
The electxic saw 86 is connected to a socket 22 on the control box 20 with a plug 89 for an electric power to operate the electric saw 86. The control sys-tem in the control box 20 is incorporated with a selector switch 24, a warning device 26, and a reset pedal 28. The control box 20 is connected to an external power source with a plug 30.
The warning device 26 is an electric or electronic alarm to give audible or visible warning signal. The warning device is preferably installed on the surface of the control box 20 or the Plectric saw 86 or other appropriate location so that it can be seen during the sawing process.
2~ 3 Please refer to Fig. 2 for the second embodiment of the control system for plaster cast saw accordin~ to the present invention. -ft is same with the embodiment shown in Fig~ 1 except a reset knob 32 is used instead of the reset pedal 28.
Please reer to Fig. 4 for a block diagram for the first embodiment of con'rol system for plaster cast saw according to the present invention. The control system comprises a power supply 40, a selector switch 24, a relay device 42, a warning device 26, and a reset device 46. The relay device 42 i6 composed of a relay 48, a driver 50 and a control circuit 52 to cut off power supply to the electric saw 86 ins-tantaneously as soon as the saw blade 88 gets contact with -the thin conductive plate 10. The reset device 46 is composed of the reset pedal 28 and a reset circuit 54 to restart the electric saw 86. The power supply 40 is connected to an external power source for pro~ision of electric power to the electric saw 86 directly, or to the elec~ric saw 86 through the relay device 42 by selection of its operator. If the selector switch 24 is located at the first contact A, the electric saw is started directly for continuous operation, the relay device 42, the warning device 26 and the reset device 46 do not function. If the selector switch 24 is located to the second contact B, the power source is not provided to the electric saw directly, but is connected to a common contact C for the relay 48 which is normally closed at NC so that the electric saw 85 can not be operated. The power source also provides an electric power to the cont~ol circuit 52 so that the control circuit is ready to receive signal and upon triggering of the reset device 46 by ~tepping the reset pedal 28, which causes the reset circuit 54 to trig~er the control circuit 52, start the driver 50 to drive to relay 48 to trip from the normal closed contact NC
to a normal open contact NO, and consequently the power supply 40 provides the electric saw 86 with an electric power through the common contact C and the norma:L open contact NO for operation o the electric saw 86. ~y this way, the electric saw 86 can be operated to cut o~f plaster cast. Whenever the saw blade 8B gets contact wi~h the thin conductive plate 10 after cutting off of the outer layer 84, the saw blade 88, the thin conductive plate 10, the warning device 26 and the control circuit 52 become a closed loop, the warning device 26 is activated to give a warning light or voice, the control circuit 52 cut off the driver 50 instantaneously so that -the relay 48 trips from the normal open contact NO to the normal closed contact NC
to cut off power supply to the electric saw 86, and consequently, the electric saw 86 is stopped Lmmediately.
Hence, the patent's skin or muscle can be prevented form hurting by the saw blade 88. To restart the electric saw 86, only the reset pedal 28 has to be stepped so that, as described above, the reset circuit 54 triggers the control 2 ~ 3 circuit 52 again to cause the driver 50 to drive the relay 48 to trip from the normal closed contact NC to the normal open contact NO, and start the electric saw 86 again.
The relay 48 of can be of solid state or mechanically controlled. ~he warning device shown in the figures is a warning indicator. It can be replaced by a buz2er to provide audible warning signal.
Please reer to Fig. 5, a block diagram for the second embodLment of -the present invention, the plug 30 t the power supply 40, the selector switch 24, the relay control device 42, the warning device 26, the electric saw, and the thin conductive plate 10 are same with that used in the first embodiment shown in Fig. 4, but an automatic reset device 56 is used instead of the reset device 46 in Fig. 4. The automatic reset device 5S can be an adjustable pulse generator which i5 triggered to send a pulse to the relay device 42 on the instant that the saw blade 88 gets contact with the thin conductive plate 10. Upon input of the pulse, the relay 48 trips from the normal open contact NO
to the normal closed contact ~C, and consequently the power supply to the electric saw 86 is cut off, the patent's skin or muscle can be prevented form hurting by the saw blade 88. After elapse of a delay time caused by the pulse, the relay 48, in the absence of pulse input, trips from the normal closed contact NC to the normal open contact NO, and ~ ~d ,1 s 1 consequently power supply to the e:Lectric saw 86 is resumed to continue the opera-tion. The length of the delay time can be adjusted by a variable resistor 58. The reset kno~
32 on the control box 20 can be -turned to adjust resistance of the variable resistor, and consequently adjust the length of delay time.
Procedures to operate the first embodiment of the electric plaster cast saw control ~ystem according to the present invention are described below:
(1) Connect the control box to an external power source with the plug 30.
15(2) Connect the electric saw 86 to the control ~ox 20 by inserting the plug 89 to the socket 22.
(3) Attach the conducti~e wlre 1~ to the extended end 12 of the thin conductive plate with -the clamp 14, and 20attach another end o~ the conductive wire 16 to the electric saw 86.
(4) Sek the selector switch 24 -to contact B position.
25(5) Step the reset pedal 28 to start the electric saw 86. The indicator of the warning device 26 is o~ at this inskant, which means that the control box 20 is in good f~
working condition.
(6) Cut off -the outer layer 84 of the plaster cast 84 by the electric saw 86. The power so-lxce is cut off and 5 the electxic saw is stopped immediately, and the indicator of the warning device 26 is on to warn khe operator not to operate the electric saw 86 on the instant the saw blade 88 gets contact with the thin condu~tive plate 10 90 that the patent's skin o~ muscle can be prevented form hurting by the saw blade 88.
(7) If required, step the reset pedal 28 to resumQ
operation of the electric saw 86. The indicator of the warning device 26 is off when the reset pedal 28 is stepped.
(8) Repeat steps (6) and (7) till the plaster cast is completely cut off.
~9) If opexation of the electric saw 86 without control of the control system according to the present invention, set the selector switch 24 at the contact A
position, then the electric saw 86 is operating continuous and will not stop when the saw blade 8~ gets contack with the thin conductive plate 10.
(10) It is recommendable to explain and demonstrate the patient the whole operating process before sawing is started.
Procedures to operate the second embodiment of the electric plaster cas-t saw control system according to the present invention are described bel~w:
(1) through (4) are same with that for the first embodiment.
(5) Turn the reset knob to select the de~ired length of delay time for interruption of the electric saw 86.
~ 6) Cut o~f the outer layer 84 of the plaster cas~ 80 by the elect~ic saw 86. The power source is cut off and the electric s~w 86 is stoppecl Lmmediately, and the indicator of the warning device 26 is on to warn the operator not to operate the electric saw ~6 on the instant the saw blade 88 gets contact with the thin concluctive plate 10 so that the patent's skin or muscle can be prevented form hurting by the saw blade 88.
(7) After elapse of the delay time, power supply to the electric saw 86 is resumed, the electric saw 86 is started again, the indicator of the warning device 26 is off.
(8) Repeat steps (6) and (7) till the pla~ter cast is completely cut off.
(9) If opera-tion of the electric ~aw 86 without control of the control system according to the present invention, set the selector switch 24 at th~ c~ntact A
position, then the electric saw 86 is operating continuous and will not stop when the saw blade 8~ gets contact with the thin conductive plate 10.
(10) It is recommendable to explain and demonstrate the pakient the whole operating process ~efore sawing is started.
While cutting off plaster cast with the control system according to the present invention, the power supply to the electric saw is cut of f instantaneously on the instant the saw blade gets contact with the thin conductive plate, and consequently, the electric saw is stopped, and the patent's skin and muscle is preven~ed from hurt which may be caused by the saw blade. With such an invention, the patent's fear can be eliminated, the operator has confidence to remove the plaster cast safely, and consequently the time required to remove the plaster cast can be shortened.
Moreover, the with the present invention, the electric saw can be operated by any nurse or operator, and hence work burden of surgeon or experienced nurse can be reduced.
25(5) Step the reset pedal 28 to start the electric saw 86. The indicator of the warning device 26 is o~ at this inskant, which means that the control box 20 is in good f~
working condition.
(6) Cut off -the outer layer 84 of the plaster cast 84 by the electric saw 86. The power so-lxce is cut off and 5 the electxic saw is stopped immediately, and the indicator of the warning device 26 is on to warn khe operator not to operate the electric saw 86 on the instant the saw blade 88 gets contact with the thin condu~tive plate 10 90 that the patent's skin o~ muscle can be prevented form hurting by the saw blade 88.
(7) If required, step the reset pedal 28 to resumQ
operation of the electric saw 86. The indicator of the warning device 26 is off when the reset pedal 28 is stepped.
(8) Repeat steps (6) and (7) till the plaster cast is completely cut off.
~9) If opexation of the electric saw 86 without control of the control system according to the present invention, set the selector switch 24 at the contact A
position, then the electric saw 86 is operating continuous and will not stop when the saw blade 8~ gets contack with the thin conductive plate 10.
(10) It is recommendable to explain and demonstrate the patient the whole operating process before sawing is started.
Procedures to operate the second embodiment of the electric plaster cas-t saw control system according to the present invention are described bel~w:
(1) through (4) are same with that for the first embodiment.
(5) Turn the reset knob to select the de~ired length of delay time for interruption of the electric saw 86.
~ 6) Cut o~f the outer layer 84 of the plaster cas~ 80 by the elect~ic saw 86. The power source is cut off and the electric s~w 86 is stoppecl Lmmediately, and the indicator of the warning device 26 is on to warn the operator not to operate the electric saw ~6 on the instant the saw blade 88 gets contact with the thin concluctive plate 10 so that the patent's skin or muscle can be prevented form hurting by the saw blade 88.
(7) After elapse of the delay time, power supply to the electric saw 86 is resumed, the electric saw 86 is started again, the indicator of the warning device 26 is off.
(8) Repeat steps (6) and (7) till the pla~ter cast is completely cut off.
(9) If opera-tion of the electric ~aw 86 without control of the control system according to the present invention, set the selector switch 24 at th~ c~ntact A
position, then the electric saw 86 is operating continuous and will not stop when the saw blade 8~ gets contact with the thin conductive plate 10.
(10) It is recommendable to explain and demonstrate the pakient the whole operating process ~efore sawing is started.
While cutting off plaster cast with the control system according to the present invention, the power supply to the electric saw is cut of f instantaneously on the instant the saw blade gets contact with the thin conductive plate, and consequently, the electric saw is stopped, and the patent's skin and muscle is preven~ed from hurt which may be caused by the saw blade. With such an invention, the patent's fear can be eliminated, the operator has confidence to remove the plaster cast safely, and consequently the time required to remove the plaster cast can be shortened.
Moreover, the with the present invention, the electric saw can be operated by any nurse or operator, and hence work burden of surgeon or experienced nurse can be reduced.
Claims (7)
1. An electric plastic cast saw control system for cutting off of plastic cast composed of an inner layer of absorbent cotton and an outer layer formed by hardened covering material, comprising - a thin conductive plate located between the inner layer and the outer layer;
- a relay device to cut off power supply to electric saw on the instant the thin conductive plate is contacted by saw blade of the electric saw; and - a reset device to drive the relay device to resume power supply to the electric saw after the power supply is cut off.
- a relay device to cut off power supply to electric saw on the instant the thin conductive plate is contacted by saw blade of the electric saw; and - a reset device to drive the relay device to resume power supply to the electric saw after the power supply is cut off.
2. An electric plastic cast saw control system as claimed in Claim 1 which further includes a warning device to give visible warning signal on the instant the saw blade gets contact with the thin conductive plate.
3. An electric plastic cast saw control system as claimed in Claim 1 which further includes a warning device to give audible warning signal at the instance the saw blade gets contact with the the conductive plate.
4. An electric plastic cast saw control system as claimed in Claim 1 which further includes a selector switch for selection of direct connection of the power source to the electric saw so that the electric saw is free from the control of the relay device.
5. An electric plastic cast saw control system as claimed in Claim 1 which further include a reset device composed of a reset circuit to trigger the relay device to resume power supply to the electric saw after the power supply is cut off, and a pedal to activate the reset circuit.
6. An electric plastic cast saw control system as claimed in Claim 5 wherein the reset device is a pulse generator which is triggered to send a pulse to the relay device on the instant that the saw blade gets contact with the thin conductive plate to stop power supply to the electric saw for a certain delay time, and to resume power supply to the electric saw after the end of the delay time.
7. An electric plastic cast saw control system as claimed in Claim 5 wherein the delay time of the pulse generated by the pulse generator can be adjusted by a variable resistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2056004 CA2056004A1 (en) | 1991-11-22 | 1991-11-22 | Electric plaster cast saw control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2056004 CA2056004A1 (en) | 1991-11-22 | 1991-11-22 | Electric plaster cast saw control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2056004A1 true CA2056004A1 (en) | 1993-05-23 |
Family
ID=4148802
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2056004 Abandoned CA2056004A1 (en) | 1991-11-22 | 1991-11-22 | Electric plaster cast saw control system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2056004A1 (en) |
-
1991
- 1991-11-22 CA CA 2056004 patent/CA2056004A1/en not_active Abandoned
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5115567A (en) | Electric plaster cast saw control system | |
| US3812858A (en) | Dental electrosurgical unit | |
| US5928158A (en) | Medical instrument with nerve sensor | |
| US5614887A (en) | Patient monitoring system and method thereof | |
| EP0060452B1 (en) | Iontophoretic device | |
| AU2002359643B9 (en) | Foot controller with interlock circuit | |
| US20030051985A1 (en) | Intelligent surgical footpedal with low noise, low resistance vibration feedback | |
| US3710787A (en) | Intermittent traction apparatus | |
| US7296571B2 (en) | Electrical cautery-oxygen safety device | |
| CA2056004A1 (en) | Electric plaster cast saw control system | |
| US4550728A (en) | Epilator | |
| EP3592263A1 (en) | Systems and methods for contactless cranio-maxillo-facial distraction | |
| GB2068829A (en) | Dust proof plaster cast cutter and a safety device therefor | |
| WO1990003772A1 (en) | Skin protective device and method | |
| CA2084772C (en) | Ultrasonic cutter | |
| JP2886657B2 (en) | Ultrasonic cutter | |
| KR940006672Y1 (en) | Cast-cutting saws | |
| CA2268010C (en) | Guard for cast cutter | |
| CN1072082A (en) | The control device of electric plaster bandage saw | |
| JP3131883U (en) | Phototherapy equipment | |
| JP2886654B2 (en) | Ultrasonic cutter | |
| CN211834617U (en) | Ultrasonic cutting blood coagulation scalpel | |
| JP3197268B2 (en) | Surgical equipment | |
| JPH03286755A (en) | Surgical operation device | |
| JP2886656B2 (en) | Ultrasonic cutter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |