JP2005211454A - Surgical excision apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easy-to-handle surgical excision apparatus capable of surely setting the number of the rotations of an instrument. <P>SOLUTION: For the surgical excision apparatus, a probe provided with a rotatable blade is attached in an interchangeable manner to the tip of a hand piece body 25 held by an operator. The hand piece body 25 is provided with a motor 43 for rotating the blade and a Hall element 44 for detecting the rotation of the motor 43. At the time of rotating the motor 43, a test current is supplied to the motor 43 from a control unit 23 and torque generated at the time is detected by the Hall element 44. Then, a decision circuit 84 identifies the kind of the probe from the size of the torque. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surgical excision apparatus used to excise tissue such as meniscus and cartilage in a joint cavity, nucleus pulposus tissue in an intervertebral disc, and the like.

2. Description of the Related Art A surgical excision apparatus is known that excises a target site while observing the inside of a body with an arthroscope when excising tissue such as a meniscus and a cartilage in a joint cavity and a nucleus pulposus tissue in an intervertebral disc.
This type of surgical excision device has a configuration in which a tool provided with a blade at the tip is attached to a handpiece body held by a practitioner, and the blade is rotated by a motor built in the handpiece body. ing. Here, the blade at the tip of the instrument is different when polishing the bone and when cutting the object. For this reason, the instrument can be exchanged for the handpiece body.

Here, when the instrument is replaced, it is necessary to set the number of rotations of the instrument according to the type of the blade. For this reason, while attaching a magnet to an instrument, a hand switch is provided with a reed switch, the type of instrument can be identified by a change in the magnetic field detected by the reed switch, and an optimum rotation speed can be set (for example, (See Patent Document 1 or Patent Document 2).
Special Table 2000-507839 Japanese Examined Patent Publication No. 7-75611

However, if a magnet is provided on the instrument side and a reed switch is provided on the handpiece body side, the apparatus becomes complicated. In addition, the apparatus becomes large and the operability is deteriorated. Furthermore, when there are many types of instruments, in order to reliably identify each instrument, it is necessary to increase the number of magnets and reed switches or to arrange them in a complicated manner, resulting in layout problems. .
The present invention has been made to solve such a problem, and an object of the present invention is to provide a surgical excision apparatus that is easy to handle and can reliably set the number of rotations of the instrument. is there.

  The invention according to claim 1 of the present invention that solves the above-mentioned problems is provided with a treatment section for excising a target site in the body at the distal end of the inner tube, and an instrument that rotatably holds the inner tube on the outer tube; A handpiece body having a housing to which the instrument can be attached and detached, and a driving source for applying a rotational driving force to the inner tube when the instrument is mounted on the housing; and setting means for setting the rotational speed of the driving source And a control unit for supplying electric power according to a set rotational speed to the drive source, and a detection means for detecting an output characteristic of the power source in the handpiece body. A determination unit for identifying the type of the appliance based on the detection result of the detection unit; and a range of rotation speeds that can be set by the setting unit based on the determination result of the determination unit. Was surgical resection apparatus which is characterized by providing and changing means for changing.

  The present invention focuses on the fact that the output characteristics of the drive source differ depending on the shape of the instrument. In this surgical excision apparatus, when a predetermined electric power is supplied to the drive source and the inner tube is rotated, the output characteristic of the drive source is detected by the detection means. The determination means identifies the type of instrument from the difference in the output characteristics. In accordance with the determination result, the changing means extracts the range of the number of rotations that can be set with the corresponding instrument from the range of the number of rotations predetermined for each instrument. The rotational speed of the treatment section can be adjusted.

The invention according to claim 2 is the surgical resection device according to claim 1, wherein the determination means calculates the torque of the drive source and identifies the type of the instrument according to the magnitude of the torque. Features.
In this surgical excision apparatus, attention is paid to torque as the output characteristic of the drive source, and the type of instrument is identified from the magnitude of the torque.

According to a third aspect of the present invention, in the surgical resection device according to the second aspect, the control unit includes an energization control means for energizing a weak current to the drive source.
In this surgical excision apparatus, a weak current is applied to the drive source before excision of the target site. The amount of weak current is determined in advance, and the type of instrument is identified from the magnitude of torque generated when this weak current is applied.

According to a fourth aspect of the present invention, in the surgical resection device according to the first aspect, the determination means determines whether the drive source requires a time required to reach a predetermined rotation speed, or the drive source is determined from the predetermined rotation speed. The time required for stopping is measured, and the type of the appliance is identified according to the measurement result.
In this surgical excision apparatus, attention is paid to the time required for the drive source for rotating the instrument to have a predetermined condition as the output characteristic of the drive source. And the kind of instrument is identified according to the length of this time.

According to a fifth aspect of the present invention, in the surgical resection device according to any one of the first to fourth aspects, the determination means has a threshold value for switching a range that can be set as the rotational speed of the drive source. And comparing the output characteristic value detected by the detecting means with the threshold value, and the changing means, based on the determination result of the determining means, a first range that can be set as the rotation speed, and the first The second range having a maximum value larger than the range is selected.
In this surgical excision apparatus, a value based on the detection result of the detection means is compared with a threshold value, and if the value based on the detection result is higher than the threshold value, the maximum value of the settable rotation speed is set to be large. To do. On the other hand, when the value based on the detection result is lower than the threshold value, the maximum value of the settable rotation speed is set to be small.

  According to this invention, since the output characteristic of the drive source when the drive source is operated in a state where the instrument is mounted on the handpiece body is detected, the type of the instrument is identified based on this output characteristic. The number of rotations that changes according to the type of instrument can be set reliably. In addition, since the type of instrument can be reliably identified with a simple configuration, the apparatus can be reduced in size and cost.

The best mode for carrying out the invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the surgical excision apparatus 1 in this embodiment is used together with an arthroscope 2 to treat an affected part (target site) in the joint lumen of the knee W.
The arthroscope 2 has a camera head 3 with a built-in image sensor, and an arthroscope insertion portion 6 is connected to the tip of the camera head 3 via an eyepiece 4 and a branch tube 5. The arthroscope insertion part 6 is inserted into the joint cavity through a trocar 7 punctured in the knee W. A water supply source 9 is connected to the trocar 7 through a water absorption tube 8. For example, physiological saline is stored in the water supply source 9. The branching unit 5 is connected to the light source device 11 through the light guide cable 10. Furthermore, the camera head 3 is connected to a video processor 13 via a cable 12, and the video processor 13 is connected to a monitor device 15 via a monitor cable 14.

  The surgical excision apparatus 1 has a handpiece 20 whose tip is inserted into the cavity of the knee W. A suction tube 21 and a power cord 22 are connected to the handpiece 20. The suction tube 21 is connected to a suction device (not shown). The power cord 22 is connected to the control unit 23. A foot switch 24 is electrically connected to the control unit 23.

  As shown in FIG.1 and FIG.2, the handpiece 20 has the handpiece main body 25 which a practitioner hold | maintains, and the probe 26 which is an instrument with which the handpiece main body 25 is mounted | worn. FIG. 2 shows, as the replaceable probe 26, a cutter 26a that is used at a low speed to cut the affected part, and a drill bar 26b that is used at a high speed to cut the bone around the affected part.

  As shown in FIG. 2, the handpiece body 25 has a substantially cylindrical housing 31. In the housing 31, a disassembly fixing ring 32 is screwed to a tip portion to which the probe 26 is attached. The disassembly fixing ring 32 fixes the lock mechanism 33 to the housing 31. Further, a connection portion 34 for connecting the power cord 22 is attached to the proximal end of the housing 31. Further, a suction hole 35 is provided in the housing 31. A suction base 36 is attached to the opening on the proximal end side of the suction hole 35. The suction tube 21 shown in FIG. 1 is attached to the suction base 36.

As shown in FIG. 3, a hollow portion 37 is formed inside the front end side of the housing 31. From the hollow portion 37, the suction hole 35 and the shaft hole 39 through which the rotary shaft 38 is inserted are extended.
Here, a valve 40 for adjusting the flow path area is mounted in the suction hole 35. A valve lever 41 is attached to the valve 40. As shown in FIG. 1, a part of the valve lever 41 protrudes to the outside of the housing 31 so as to accept the operation of the practitioner.

As shown in FIG. 3, the shaft hole 39 is provided on the central axis of the housing 31 along the axis.
The rotating shaft 38 penetrates through the shaft hole 39 and is rotatably supported by the housing 31 with a bearing (not shown). An engaging claw 42 that engages with the probe 26 is provided at the tip of the rotating shaft 38 that protrudes into the cavity 37. On the other hand, as shown in FIG. 4, the base end portion of the rotary shaft 38 is connected to a motor 43 that is a drive source.
A brushless motor is used as the motor 43. For this reason, a hall element 44 (detection means) for detecting the rotational position of the rotor of the motor 43 is attached to the handpiece body 25.

As shown in FIG. 3, the lock mechanism 33 includes a cylindrical inner cylinder portion 45 that is engaged with the distal end opening of the housing 31 by the disassembly fixing ring 32, and a plurality of members disposed at the distal end portion of the inner cylinder portion 45. The lock pin 46 includes a finger ring 47 that covers the lock pin 46 and is slidably attached to the inner cylinder portion 45.
In the inner cylinder portion 45, an engagement groove 50 with which the disassembly fixing ring 32 is engaged is provided on the outer periphery of the base portion on the housing 31 side. In addition, a stopper projection 51 is provided in an annular shape along the circumferential direction on the inner periphery of the base portion. As shown in FIG. 5, six through holes 52 that penetrate through the wall portion in the radial direction of the inner cylinder portion 45 are provided at the front end portion of the inner cylinder portion 45 at equal intervals. A lock pin 46 is inserted into each of the through holes 52 so as to advance and retract from the outside. The lock pin 46 has a head having a diameter larger than that of the through hole 52, and the head is prevented from falling out radially inward.

  As shown in FIG. 3, the finger ring 47 is provided so as to cover the distal end portion of the inner cylinder portion 45 from the outer side in the circumferential direction. A spring 53 that can expand and contract along the axis of the lock mechanism 33 is disposed between the finger ring 47 and the inner cylinder portion 45. For this reason, the finger ring 47 is always urged toward the tip side. Furthermore, an annular groove 54 that abuts against the head of the lock pin 46 is provided on the inner periphery of the finger ring 47. The annular groove 54 is provided with an annular tapered surface 54a that decreases the width of the groove toward the outside in the radial direction. The installation position of the annular groove 54 is a position where the lock pin 46 is pressed radially inward by the tapered surface 54a when the finger ring 47 is in a natural state. For this reason, when the finger ring 47 is slid toward the housing 31 against the spring 53, the engagement between the annular groove 54 and the lock pin 46 is released.

Two types of probes 26 as shown in FIG. 2, that is, one of the cutter 26 a and the drill bar 26 b are attached to the handpiece body 25 configured as described above.
As shown in FIGS. 2 and 6, the cutter 26 a includes an outer probe 61 (outer tube) and an inner probe 62 (inner tube) that is rotatably supported in the outer probe 61.

The outer probe 61 includes an outer main body portion 63 mounted in the lock mechanism 33 and a hollow outer insertion portion 64 attached to the distal end surface of the outer main body portion 63.
The outer insertion portion 64 extends so that its axis coincides with the axis of the outer main body 63. A part of the curved surface shape is cut off at the distal end of the outer insertion portion 64 to form an opening 65.
The outer main body 63 is made of a substantially cylindrical member. The base end of the outer main body 63 has a reduced outer diameter, and an O-ring 66 that is a seal member is attached thereto. Further, in the outer main body 63, an annular groove 63b is provided on the outer periphery from the shoulder 63a, which is a step formed with a reduced diameter, to the tip. The groove 63b has a taper that increases the groove width toward the radially outer side. The groove 63b is formed to engage with the lock pin 48 on the handpiece body 25 side shown in FIG. Further, a protrusion 63 c is provided on the outer periphery on the distal end side of the outer main body portion 63. A through hole 67 is formed in the outer main body 63 along the axis. The inner probe 62 is inserted into the through hole 67 and the outer insertion portion 64.

The inner probe 62 includes an inner body portion 68 that is rotatably supported by the outer body portion 63, and an inner insertion portion 69 that extends from the tip of the inner body portion 68.
In the inner main body portion 68, a portion protruding from the base portion of the outer main body portion 63 is a port 71 in which a through hole is formed. The port 71 communicates with a suction hole 72 that penetrates to the distal ends of the inner main body portion 68 and the inner insertion portion 69. Further, a plate-like tongue-like portion 70 extends from the rear end of the port 71. The tongue 70 is engaged with the engaging claw 42 of the rotating shaft 38 of the handpiece body 25 shown in FIG.
The inner insertion portion 69 extends so that its axis coincides with the axis of the inner main body portion 68. Further, the axis line of the inner insertion portion 69 also coincides with the axis line of the outer insertion portion 64. The outer diameter of the inner insertion portion 69 is smaller than the inner diameter of the outer insertion portion 64. Therefore, the inner insertion portion 69 is accommodated in the outer insertion portion 64 except for the tip portion. A blade (treatment section) 73 that cuts out the target portion by rotation is attached to the distal end portion of the inner insertion portion 69 exposed from the outer insertion portion 64. Further, a window (not shown) is formed in the vicinity of the distal end of the inner insertion portion 69 so that the excised tissue can be discharged through the inner insertion portion 69 and the handpiece body 25.
Note that the outer probe 61 and the inner probe 62 of the cutter 26a have substantially rotationally symmetric shapes with respect to the same axis.

  As shown in FIG. 2, the drill bar 26b has a blade 74, which is a treatment portion at the tip of the inner probe 62, which has a larger outer diameter than the blade 73 of the cutter 26a and has a different blade shape. Have the same configuration. Therefore, the description is omitted. Since the drill bar 26b is used to cut bones and the like, the blade 74 is often rotated at a higher speed than the blade 73 of the cutter 26a.

Next, the configuration of the control unit 23 and the foot switch 24 that control the operation of the handpiece 20 will be described with reference to FIG.
The control unit 23 includes an interface circuit 81, a detection circuit 82, a motor driver 83 (energization control unit), a determination circuit (determination unit) 84, an operation unit 85 and a display unit 86, which are setting units, A power supply circuit and a control device 87 are provided.
The interface circuit 81 plays a role of passing a signal output from the foot switch 29 to the control unit 87. The detection circuit 82 receives a rotational position signal detected by the Hall element 44 in the handpiece body 25 and outputs the signal to the determination circuit 84 and the control unit 87. The motor driver 83 receives a drive command from the control unit 87 and generates a current for energizing the motor 43. Further, the motor driver 83 outputs information on the current supplied to the motor 43 to the determination circuit 84. The determination circuit 84 calculates the difference between the target position of the rotary shaft 38 and the actual rotational position from the detection signal of the Hall element 44 and information on the current supplied to the motor 43, and based on this, the rotation of the probe 26 is calculated. The necessary torque is calculated and the type of the probe 26 is identified. The operation unit 85 includes, for example, a changeover switch and a button. The operation unit 85 receives an operation performed by the practitioner such as turning on or off the power supply and setting the number of rotations of the probe 26 and transmits a predetermined signal to the control unit 87. The display unit 86 includes, for example, a liquid crystal panel, and displays information indicating the operation state of the handpiece 20, particularly the rotation speed of the probe 26. The control part 87 controls each part 81-86. The control unit 87 also has a function as a changing unit that sets a range of rotation speeds that can be set as the rotation speed of the probe 26. The range of the rotational speed is registered in advance for each type of the probe 26, and an appropriate rotational speed range is set based on the determination result of the determination circuit 84.

Here, an example of the operation unit 85 and the display unit 86 will be described with reference to FIG.
In FIG. 7, the operation unit 85 and the operation unit 85 are concentrated on the front surface of the control unit 23. Specifically, a connector 90 to which the power cord 22 is connected is provided at the lower right of the front surface. A power switch 91 and a power display LED 92 are arranged on the lower left of the front surface. In the center of the front face, a rotation speed increase switch 93, a rotation speed decrease switch 94, a set rotation speed display section 95, and a set rotation speed display LED 96 are arranged. The rotation speed increase switch 93 and the rotation speed decrease switch 94 are switches for setting the rotation speed of the inner probe 62, that is, the rotation speed per unit time. Here, the edge of the rotation speed increase switch 93 is colored red. The set rotation speed display unit 95 displays the set rotation speed by numbers. The set rotation speed display LED 96 turns on a plurality of LEDs (light emitting diodes) stepwise according to the set rotation speed.
Further, a minimum rotation number display unit 97 and a maximum rotation number display unit (threshold value display unit) 98 are arranged so as to sandwich the set rotation number display unit 95, and can be set as the rotation number of the probe 26. The minimum number of rotations and the maximum number of rotations (threshold value) are displayed. FIG. 7 shows a state in which “500” and “6000” are displayed on both display portions 97 and 98, respectively, as an initial state when the power is turned on.

  In the control unit 23 as shown in FIG. 7, when either the rotation speed increase switch 93 or the rotation speed decrease switch 94 is intermittently pressed, the rotation speed displayed on the set rotation speed display section 95 changes. It has become. And the control part 87 receives operation of the rotation speed increase switch 93 or the rotation speed decrease switch 94 within the range of the rotation speed shown by both the display parts 97 and 98. FIG. Note that the rotation speed increase switch 93 has a function of changing the threshold value by pressing and holding for one second or longer. When the rotation speed increase switch 93 is pressed and held in this way, the maximum rotation speed is changed to, for example, 10,000. At this time, the display of the maximum rotation speed display section 98 is also changed to “10000”.

  As shown in FIG. 4, the foot switch 24 includes a right pedal 24 a for rotating the motor 43 built in the handpiece body 25 to the right and a left pedal 24 b for rotating the motor 43 to the left. When the practitioner steps on these pedals 24a and 24b with his / her foot, the motor 43 rotates at the speed of the set rotational speed displayed on the set rotational speed display section 95 (see FIG. 7). The blades 73 and 74 (see FIG. 2) also rotate through 62.

Next, operation | movement of this surgical excision apparatus 1 is demonstrated.
Prior to the treatment by the surgical excision apparatus 1, an arthroscope 2 as shown in FIG. 1 is inserted into the joint cavity to confirm the target site. Specifically, physiological saline is sequentially introduced from the water supply source 9 into the joint cavity, the waste is removed, and the periphery of the target site is illuminated with light introduced from the branching unit 5. Then, the target part is imaged by the camera head 3 and displayed on the monitor device 15.

After confirming the target site with the arthroscope 2, the probe 26 is attached to the handpiece body 25. For example, when the cutter 26a is mounted, the finger hook ring 47 of the lock mechanism 33 shown in FIG. 3 is slid toward the disassembly fixing ring 32 side. At this time, the engagement between the annular groove 54 on the inner peripheral side of the finger ring 47 and the lock pin 46 is released, and the lock pin 46 can move radially outward.
In this state, the cutter 26a is inserted into the cavity portion 37 of the housing 31, and the shoulder portion 63a of the outer main body portion 63 and the stopper projection 51 of the inner cylinder portion 45 of the lock mechanism 33 are engaged. As a result, the O-ring 66 of the outer main body 63 comes into contact with the stopper protrusion 51, and a watertight structure is formed. Further, the protrusion 63c of the outer main body portion 63 engages with an engagement groove (not shown) of the inner cylinder portion 45, and the rotation of the outer main body portion 63 is prevented. Further, the tongue 70 on the inner probe 62 side engages with the engaging claw 42 of the rotating shaft 38.
Thereafter, when the hand is released from the finger ring 47, the finger ring 47 is slid to the tip side by the spring 53. At this time, the lock pin 46 moves radially inward so as to be pressed by the tapered surface 54a of the annular groove 54, and engages with the annular groove 63b of the outer main body 63 of the cutter 26a. Thereby, the cutter 26a is attached to the handpiece body 25.

When the mounting of the probe 26 is completed, the control unit 23 is turned on. The control unit 23 sets the maximum number of rotations, that is, determines a range of the settable number of rotations according to the flowchart shown in FIG.
That is, when the control unit 23 is powered on, the control unit 87 instructs the motor driver 83 to operate in the test mode, and the motor driver 83 supplies the test current to the motor 43 (step S11). The test current at this time is a weak current that is smaller than the value of current that is supplied to the motor 43 during treatment. Information on the current value of the test current is passed to the determination circuit 84.

  When the power is turned on and a test current is supplied to the motor 43, the motor 43 starts to rotate, and the Hall element 44 detects the rotational position (step S12). Specifically, the hall element 44 generates a current corresponding to a change in magnetic flux density with the magnet of the rotor and outputs the current to the detection circuit 82. Then, information on the rotational position of the motor 43 is transferred to each of the control unit 87 and the determination circuit 84.

  The determination circuit 84 calculates a torque necessary for the rotation of the probe 26 by searching a map prepared in advance based on the difference between the current value of the test current and the rotation position information (step S13). ). For example, the rotational speed of the motor 43 when the test current is supplied with the probe 26 not attached is stored in advance, and this rotational speed and the actual rotational speed of the motor 43 with the probe 26 attached. Investigate the difference. In this case, the greater the difference between the two, the greater the calculated torque value. Then, the determination circuit 84 determines the type of the probe 26 based on the calculated torque information. That is, the magnitude of the calculated torque and a preset torque threshold value a are compared (step S14). If the calculated torque is greater than the threshold value (Yes in step S14), the maximum rotational speed is set as a relative value. A command signal for lowering the first value (for example, 6000 rpm, Low) is output to the controller 87 (step S15).

In response to the command signal, the control unit 87 extracts a rotation speed range in which the maximum rotation speed is the first value from the data registered in the memory. Furthermore, the display on the display unit 86, for example, the display on the minimum rotation number display unit 97 and the maximum rotation number display unit 98 shown in FIG.
Then, the practitioner sets the rotational speed within this range (step S16), and when the foot switch 24 is turned on (Yes in step S17), the motor driver 83 is turned on, that is, a drive signal is output (step S18). ). On the other hand, when the foot switch 24 is not operated (No in step S17), the motor driver 83 is turned off and no drive signal is output (step S19).

On the other hand, when the torque calculated by the determination circuit 84 is equal to or less than the preset threshold value a (No in step S14), the second value (the maximum value is greater than the first value). For example, a command signal for setting the rotation to 10,000 rpm is output to the control unit 87 (step S20). In response to the command signal, the control unit 87 extracts a rotation speed range in which the maximum rotation speed is the second value from the data registered in the memory. Further, the display of no display 6 is changed so that the input of the rotation speed outside this range is not accepted.
Then, the practitioner sets the rotation speed within this range (step S21), and when the foot switch 24 is turned on (Yes in step S22), the motor driver 83 is turned on, that is, a drive signal is output (step S23). ). On the other hand, when the foot switch 24 is not operated (No in step S20), the motor driver 83 is turned off and a drive signal is output (step S24).

  Thus, in this embodiment, focusing on the fact that the torque required for rotation differs depending on the type of probe 26 attached to the handpiece body 25, the rotational position when a weak test current is applied to the motor 43. The type of the probe 26 is automatically identified based on (the number of revolutions), and the setting of the number of revolutions is accepted within a preset range for each probe 26. For this reason, the probe 26 can be rotated at an appropriate number of rotations. Here, since the Hall element 44 necessary for controlling the motor 43 is used as the means for detecting the torque, it is not necessary to add a new component to each connection portion of the probe 26 and the handpiece body 25. . Therefore, the apparatus can be miniaturized, the probe 26 can be easily attached and detached, and the operability is improved. Note that such a test mode has an advantage that the type of the probe 26 can be automatically identified immediately before the treatment because the test current is applied for a short time.

  Here, a switch for stopping energization of the test current and releasing the test mode may be provided in the control unit 23, and torque detection may always be performed until this switch is operated. This switch may be a dedicated switch or may be shared with other switches.

Further, the output characteristics of the motor 43 acquired for automatically identifying the type of the probe 26 are not limited to torque.
For example, the determination circuit 84 may be a circuit that identifies the type of the probe 26 based on the time required for the rotation speed of the motor 43 to reach a predetermined value.
Such a determination circuit 84 measures the time until the number of rotations reaches a predetermined value when the motor 43 is rotated with the probe 26 mounted, and the measurement result is equal to or less than a preset threshold value. In this case, a command is sent to the controller 87 so as to set a relatively low first value (Low) as the maximum rotational speed. On the other hand, when the measurement result exceeds the threshold value, a command is sent to set a second value (High) larger than the first value as the maximum rotation speed.
In this case, the predetermined number of rotations may be the number of rotations when the test current is applied or the number of rotations set by the practitioner. Further, the rotational speed of the motor 43 is calculated from the detection result of the Hall element 44. It is also possible to measure the time constant and identify the type of probe 26 according to the time constant.

The determination circuit 84 may be a circuit that identifies the type of the probe 26 based on the time required for the motor 43 to stop. In this case, the motor 43 is rotated at a predetermined number of rotations with the probe 26 initially attached. Thereafter, the energization to the motor 43 is stopped, and the time until the motor 43 stops is measured. If the time required for the stop is equal to or less than a preset threshold value, a command is sent to the control unit 87 so as to set a relatively low first value (Low) as the maximum rotation speed. On the other hand, when a time exceeding the threshold is required, a command is sent to set a second value (High) larger than the first value as the maximum rotation speed.
The predetermined number of rotations in this case may be the number of rotations when a test current is applied or the number of rotations set by the practitioner. Further, the rotational speed of the motor 43 is calculated from the detection result of the Hall element 44.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, the control unit of the control unit may have two or more threshold values. When there are three or more types of probes 26, the probes 26 can be identified. In this case, if the output characteristics of the motor 43 when three or more types of probes 26 are attached are stored in the control unit 23 in advance, it can be handled by internal processing. Therefore, even when the types of the probes 26 are increased, the probes 26 can be reliably identified with a small device, and can be rotated at an appropriate rotation speed.
Further, the probe 26 may be configured such that a part of the outer insertion portion 64 is made of a flexible member and this part can be bent. In this case, it is comprised from a flexible member so that the inner insertion part 69 inserted in the outer insertion part 64 may also be bent.

It is a figure which shows the structure of the surgical excision apparatus in embodiment of this invention, Comprising: It is explanatory drawing which shows a mode that treatment is performed using an arthroscope. It is a schematic block diagram of a handpiece. It is sectional drawing of the front-end | tip part of a hand port main body. It is a figure which shows the structure of a surgical excision apparatus, Comprising: It is a figure which shows the structure of a control unit especially. It is sectional drawing along the XX line of FIG. It is sectional drawing of a probe. It is a figure which shows an example of the operation part and display part of a control unit. It is a flowchart which shows the process of a surgical excision apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surgical excision device 23 Control unit 25 Handpiece main body 26 Probe (instrument)
31 Housing 43 Motor (drive source)
44 Hall element (detection means)
64 Outer insertion part (outer tube)
69 Inside insert (inner tube)
73, 74 Blade (treatment section)
83 Motor driver (energization control means)
84 determination circuit (determination means)
85 Operation unit (setting means)
86 Display (setting means)
87 Control unit (change means)
a Threshold

Claims (5)

A treatment part for excising the target site in the body at the tip of the inner tube, and an instrument in which the inner tube is rotatably held by the outer tube;
A handpiece body including a housing to which the instrument can be attached and detached, and a drive source that applies a rotational driving force to the inner tube when the instrument is mounted on the housing;
A control unit having setting means for setting the rotational speed of the drive source, and supplying power to the drive source according to the set rotational speed;
A surgical resection device comprising:
In the handpiece body, provided in the detection means for detecting the output characteristics of the power source,
A determination unit that identifies the type of the appliance based on a detection result of the detection unit, and a change unit that changes a rotation speed range that can be set by the setting unit based on the determination result of the determination unit. And a surgical excision device.   The surgical ablation apparatus according to claim 1, wherein the determination unit calculates a torque of the drive source and identifies the type of the instrument according to the magnitude of the torque.   The surgical excision apparatus according to claim 2, wherein the control unit includes an energization control means for energizing the driving source with a weak current.   The determination means measures the time required for the drive source to reach a predetermined rotational speed, or the time required for the drive source to stop from the predetermined rotational speed, and determines the type of the instrument according to the measurement result. The surgical ablation device according to claim 1, wherein the surgical resection device is identified. The determination means has a threshold value for switching a range that can be set as the rotation speed of the drive source, compares the output characteristic value detected by the detection means with the threshold value, and the change means The first range according to any one of claims 1 to 4, wherein a first range that can be set as a rotational speed and a second range having a maximum value larger than the first range are selected based on the determination result. The surgical excision device according to any one of the preceding claims.

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