JPH0341924A - Endoscope device - Google Patents

Abstract

PURPOSE:To widen the control range of a driving member and to greatly bend the bending part by bringing a resistance value to logarithm.exponent transformation and transforming it to a resistance value brought to linear variation, when the electric resistance value of the driving member is varied non-linearly against a temperature. CONSTITUTION:On the base end side of a tip part 6, a bending part 7 is provided, and a driving member 8 is incorporated in the axial direction of the bending part 7. The driving member 8 is constituted of a shape memory alloy, and when it is heated exceeding a transportation point temperature, it is deformed to a shape stored in advance and the bending part 7 is bent. To the driving member 8, one end of an electric wire 9 is connected, and the other end is connected to a resistance value detecting part 11 in a light source device 8 through a connector device 5a. The resistance value detecting part 11 is connected to a resistance value linear variation part detecting part 12 and a logarithm.exponent transformation part 22. The resistance value of the driving member 8 is detected by the resistance value detecting part 11, and the result of detection is outputted to these resistance value linear variation part- detecting part 12 and the logarithm.exponent transformation part 22. Also, a resistance value detecting means 10 is constituted of the resistance value detecting part 11 and the resistance value linear variation part detecting part 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a curved section 11 having a bending device for bending a curved section of an insertion section using a heat-sensitive deformable member disposed on the curved section.
It is related to the device.

[Prior Art and Problems to be Solved by the Invention] In recent years, a long and narrow insertion section has been inserted into a body cavity to observe the inside of the body cavity, and treatment tools have been used to perform treatment as necessary. Alternatively, endoscope devices capable of inserting the insertion portion into a lumen and observing the inside of the lumen are widely used.

The observation site inside these body cavities and lumens is rarely located in the direction of entry of the insertion section, so when performing observations, etc., bend the curved section provided at the distal end of the insertion section. By operating the tip, the tip can be directed toward the region to be observed.

As a means for bending this bending section, an operating wire is inserted into the insertion section, one end of the operating wire is fixed to the distal end side of the bending section, and the proximal end is attached to a bending operation knob provided on the operating section. A technique is generally used in which the operating wire is connected to the wire and the bending operation knob is used to pull or relax the operating wire to curve the curved portion, thereby directing the tip toward the observed area.

However, such a configuration inevitably complicates the structure and may lead to an increase in the diameter of the insertion portion.
Since a relatively large operating force is required, it is difficult to improve operability.

Therefore, for example, in Japanese Patent Application Laid-open No. 63-292933,
A technique has been disclosed in which a drive member made of a heat-sensitive deformable member such as a shape memory alloy is disposed in the curved portion, and the drive member is heated and deformed by electricity, thereby making it possible to curve the curved portion.

The amount of curvature of the curved portion can be controlled by detecting the resistance value of the shape memory alloy and changing the amount of current applied to the shape memory alloy based on the detection result. .

However, this is due to the property that the electrical resistance value of the shape memory alloy U does not change linearly with temperature.

That is, as shown in Fig. 9, when the humidity is between 11 and 12, the resistance value changes linearly from R1 to R2;
In a temperature range below or above 12, the change in resistance value R with respect to a change in temperature becomes gradual.

Therefore, in the technique of using a heat-sensitive deformable member as a driving member, the bending operation is controlled within a humidity range in which the electrical resistance value of the driving member changes linearly, that is, a temperature range between T1 and T12.

Therefore, the controllable range is limited, and it is difficult to set a large amount of curvature of the curved portion.

[Purpose of the Invention] The present invention has been made in view of these circumstances, and when the electrical resistance value of the driving member changes non-linearly with respect to temperature, the resistance value is transformed into logarithms and exponentials. The object of the present invention is to provide an endoscope device that widens the control range of the drive member and makes it possible to greatly curve the curved portion by converting the resistance value into a resistance value that changes linearly.

[Means and effects for solving the problem] The endovascular mirror device according to the present invention includes a drive member made of a heat-sensitive deformable member disposed in the insertion section, and an energization device that applies electricity to the drive member to bend the drive member. means, a resistance value detection means capable of detecting a region where the electrical resistance value of the driving member changes linearly with respect to temperature and a region where it changes non-linearly; a conversion means for converting the resistance value into a resistance value that changes linearly by logarithmically or exponentially converting the resistance value when the resistance value changes; It is equipped with a control means capable of controlling the amount of current supplied.

With this configuration, in a region where the electrical resistance value of the drive member changes non-linearly with respect to temperature, the resistance value is converted into a resistance value that changes linearly by logarithmically or exponentially converted by the conversion means. Based on this converted value, the amount of current applied to the drive member by the current supply means is controlled via the control means.

[Embodiments of the invention] Hereinafter, the present invention will be described in detail with reference to the drawings.

1 to 5 relate to the first embodiment of the present invention, in which FIG. 1 is a schematic configuration diagram of the system, FIG. 2 is a block diagram of a resistance value linear change section detection circuit, and FIG. 3 is a resistance value straight line. FIG. 4 is a waveform diagram for explaining part of the operation of the changing portion detection circuit, FIG. 4 is a block diagram of the logarithm/exponential conversion portion, and FIG. 5 is a characteristic diagram of changes in electric resistance value with respect to temperature changes of the drive member.

In these figures, numeral 1 is an endoscope, and 2 is a light source device.

The endoscope 1 has an elongated and flexible insertion section 3 that can be inserted into a body cavity, etc., and a large-diameter operation section 4 connected to the proximal end of the intermediary section 3. A universal cord 5 extends from one side of the operating section 4. A connector device 5a connected to the connector receiver of the light source device 2 is provided at the tip of the universal cord 5,
The universal cord 5 is connected to the light source device 2 via this connector device 15a.

The illumination light from the light source device 2 is guided to the distal end portion 6 through a light guide disposed within the insertion portion 3, and is configured to be able to irradiate the region to be observed.

Further, a curved portion 7 is provided on the base end side of the distal end portion 6,
A driving member 8 made of, for example, a band-shaped heat-sensitive deformable member is housed in the curved portion 7 in the axial direction of the curved portion 7 . This drive part shrine 8 is made of a shape memory alloy such as a Ti-Ni alloy or a Cu-Zn-Aj alloy, and deforms into a pre-memorized shape when heated above the transformation point temperature. By doing so, the curved portion 7 can be curved.

One end of a pair of electric wires 9 is connected to this drive unit IA8. The other end of the electric wire 9 is extended into the universal cord 5 via the operating section 4, and connected to the resistance value detection section 11 provided within the light source device 8 via the connector device 5a. It has become.

Further, this resistance value detection section 11 is connected to a resistance value linearity detection circuit 12 and a logarithmic/exponential conversion section 22 which is an example of a conversion means, so that the resistance value of the drive section I48 is connected to the resistance value detection section 11. The detection result is outputted to the resistance value linearization unit detection circuit 12 and the logarithm/exponential conversion unit 22. Note that the resistance value detection unit 11 and the resistance value linearity detection circuit 12 constitute the resistance value detection means 10.
is configured.

As shown in FIG. 2, the resistance value linearization unit detection circuit 12
means for measuring the change in the electrical resistance value of the drive unit 8 due to initial energization, detecting the range in which the resistance value changes linearly as shown as R1-R2 in FIG. 5, and storing this. Based on this detection result, it is determined whether the electrical resistance value of the driving member 8 during actual driving is in a region where it changes linearly, and the result is transmitted to the conversion control unit 21.
It consists of means for outputting to.

The electrical resistance value of the drive member 8 detected by initial energization is
The signal is input to a gate circuit 13 disposed within the resistance value linearization unit detection circuit 12. The gate circuit 13 receives an initial energization control signal from the energization control section 26 as shown in FIG. 3(a). Furthermore, at the same timing as the initial energization control signal, the energization circuit 27 energizes the driving member 8 with a current as shown in FIG. 3(b). Then, as shown in FIG. 3(C), the electric resistance ratio detection signal B of the drive unit jfA8 during the initial voltage
Only this is output to the differential circuit 14 and the storage section 18 at the subsequent stage. In the differentiating circuit 14, the third
As shown in Figure (d), a differential output signal is output to the comparator circuit (a) 15 that becomes zero during a period in which the input electrical resistance value detection signal undergoes a linear change. This comparison circuit (a
) 15, during the period when the input signal is zero,
It is designed to output a signal as shown in FIG. 3(e). That is, the period during which the signal is output from the comparator circuit (a) 15 coincides with the period during which the electrical resistance value of the driving member 8 is changing linearly.

Therefore, based on the rise of the output signal 8 from the comparison circuit (a,) 15, a trigger signal as shown in FIG. 3(f) is output from the trigger signal generation circuit (a) 16, and the driving member
A resistance value signal in which the electrical resistance value starts to show a linear change is stored in the storage unit 18.

Also, based on the fall of the output signal from the comparison circuit (a) 15, the trigger signal generation circuit (b) 17hs and the like shown in FIG.
A trigger signal as shown in 0> is output, and the storage unit 18 stores a threshold value at which the electrical resistance value of the driving member 8 changes non-linearly from a region where it shows a linear change to a region of −46. The resistance value signal is stored.

As described above, upon initial energization, the resistance value linear change section of the drive section +48 is detected and stored.

Further, when the drive member 8 is actually operated, the output of the resistance value detection section 11 and the two values indicating the resistance value linear change section detected and stored by the above-mentioned initial energization are detected by the comparator circuit. (b) Compare in 19. The output signal of this comparison circuit (b) 19 is input to a logic circuit 20, and in this logic circuit 20, a region where the resistance value of the drive member 8 changes linearly (between R1 and R2) Then, it is determined which region exists in the non-linear region where the resistance value is saturated (R+ or more) or the non-linear change region where the resistance value is asymptotically approached (R2 or less), and depending on the result, The resulting signal is outputted as an output of the resistance value linearization unit detection circuit 12 to the conversion il control unit 21 disposed within the light source device 2.

As shown in FIG. 4, the conversion control section 21 is connected to a changeover switch 23 disposed within the logarithmic/exponential conversion section 22, and a single output terminal 23a provided on this changeover switch 23. Three input terminals 23b, 23c, 23d
The connection between the converter 1111IK1 section 21 is switched by the output from the converter 1111IK1 section 21 described above.

The output terminal 23a is connected to an energizing section 26, which is an example of a control means provided in the light source device 2, while the three input terminals 23b and 23c.

An input terminal 23C disposed at the center behind 23d is connected to the resistance value detection section 11. Further, a logarithmic conversion circuit 24 is interposed between the resistance value detection section 11 and the input terminal 23b.
An index conversion circuit 25 is interposed between the input signal and the input signal 3d. When the input terminal 23b and the output terminal 23a are connected, a signal obtained by logarithmically converting the output of the resistance value detection section 11 in the logarithmic conversion circuit 24 is input to the energization control section 26. On the other hand, when the input terminal 23d and the output terminal 23a are connected, a signal obtained by index-converting the output of the resistance value detection section 11 in the index conversion circuit 26 is input to the energization control section 26. Further, when the output terminal 23a is connected to the input terminal 23G, the output of the resistance value detection section 11 is outputted to the energization control section 26 as the output of the logarithmic/exponential conversion section 22. ing.

Therefore, when the resistance value of the drive member 8 detected by the resistance value detection section 11 is equal to or higher than R1 shown in FIG. First, when R2 or less, index conversion is performed.

In addition, the above-mentioned energization unit to which the output of this logarithm/exponential conversion unit 22 is inputted! The 1111it section 26 is connected to an energizing circuit 27 as an energizing means connected to the electric wire 9 and the resistance value detecting section 11 . The '-A electric circuit 27 energizes and heats the drive section 448 via the electric wire 9 by a signal from the energization control section 26 using, for example, a pulse width modulation method. The electric resistance value of the drive IJJ member 8 is detected by the signal from the drive IJJ member 8 during the period when the power supply to the drive member 8 is stopped.

When performing observation or treatment using such a configuration, the endoscope 1 and the light source device 2 are connected via the connector device @5a, and the insertion section 3 is inserted into the body reservoir or tube. In the state inserted into the hole, the energization circuit 27 is controlled by the signal from the energization t1111111 section 26, and the energization circuit 27 energizes the driving member 8 via the current IIA9. Zuruto,
This driving member 8 is deformed by being heated, and the bending portion 7 is flexed in accordance with this deformation.

By the way, when the drive member 8 is deformed, the electrical resistance value of the drive member 8 changes. This resistance value is the driving member 8
The resistance value is detected by the resistance value detection unit 11 during the suspension period of energization, and the detected result is detected by the resistance value linearity unit detection circuit 12.
and is output to the logarithm/exponential conversion circuit 22.

Then, the resistance value linearity detecting circuit 12 determines whether the electric resistance value of the drive unit 448 is in a non-linear region where it saturates to a maximum resistance value of R1 or more shown in FIG. It is determined whether the resistance is in a linear change region or in a non-linear region that gradually approaches a minimum resistance value of R2 or less, and the determined result is output to the conversion control section 21.

Next, the conversion control unit 21 generates a control signal based on the signal input from the resistance linearity unit detection circuit 12, and this control signal is input to the logarithmic/exponential conversion unit 22. , the output terminal 23a and the input terminals 23b, 23c, 2 of the changeover switch 23 of the logarithm/exponential conversion section 22.
3d is switched to an appropriate combination.

Then, the electric resistance value of the driving member 8 becomes tR as shown in FIG.
When it is 1 or more, the output terminal 23a is connected to the input terminal 23b, so that the signal detected by the resistance value detection section 11 is logarithmically converted and inputted to the energization control section 26 as the output of the conversion section 22. . Further, when the electrical resistance value of the drive member 8 is between R1 and R2, the central input terminal 23c and the output terminal 23a are connected, and the detection result by the resistance value detection section 11 itself is transmitted to the energization control section. 26. Furthermore, when the swamp resistance value is equal to or lower than R2, the output terminal 23a is connected to the input terminal 236, so that the detection result of the resistance value detection section 11 is converted into an index and the output of the conversion section 22 is output. It is input to the energization control section 26.

As a result, even if the electrical resistance value of the drive member 8 with respect to temperature has a characteristic as shown by the broken line in FIG. 5, the non-linear region changes linearly as shown by the solid line in FIG. This converted I! f, resistance value is energized Il
It will be input to the l i section 26.

Then, based on this input resistance value, the energization control section 2
By controlling the energizing circuit 27 /)<tJI at 6, the position of energizing the driving member 8 is controlled.

Therefore, it is possible to accurately i11@ the driving member 8 not only when the electrical resistance value of the driving member 8 is in the linear variation region but also when it is in the non-linear region, and the curved portion 7 It becomes possible to set a large amount of curvature.

The shape of the drive member 8 is not limited to a belt shape, but can also be formed into a plate shape, a coil shape, etc., and the drive member 8 can be made of not only a shape memory alloy but also a heating coil attached. It is also possible to form it from a material such as shape memory plastic.

Moreover, the driving member 8 can be not only built into the curved portion 7 but also provided outside thereof.

Furthermore, in this embodiment, the resistance value detection means 10 and the control means 26
Although an example has been described in which these devices and means are arranged within the light source device 2, these devices and means should not be limited to this example, and can be formed separately from the light source device 2 as other devices. It is.

6 and 7 relate to a second embodiment of the present invention, FIG. 6 is a block diagram of the light source device, and FIG. 7 is a waveform diagram of the voltage supplied to the driving member. Incidentally, the same members and members having the same functions as those in the first embodiment described above are given the same reference numerals, and explanations thereof will be omitted.

In this embodiment, an A/D converter 55 is connected to the resistance value detection section 11 in place of the resistance value linearization section detection circuit 12 described in the first embodiment, and a logarithmic/exponential conversion circuit 22 is connected to the resistance value detection section 11. Instead, the PAfB section 56 is interposed between the upper A/D converter 55 and the energization control section 26.

Then, the energizing circuit 27 energizes a driving member (not shown) f'i using a pulse modulation method, while the electrical resistance value of this driving member is detected by the resistor 1 detection unit 11 during the period when the energization is stopped. The detection result is sent to the A/D converter 551.
．． :teRn, Rn+1. Rn+2-, -... are sampled and output to the calculation section 56.

Based on the sampled resistance values, this calculation unit 56 calculates the values of Δa, Δb, and so on by performing calculations of Δa=Rn+1−Rn, Δb=Rn+2−Rn+1, and Δa= In the case of Δb, Rn+2 is output to the general control unit 26 as the electrical resistance value of the driving member, while
In the case of Δa≠Δb, 20 l g g (A:/(Δ b −Δ
a)) Determine the value of Rn+2 (where is a constant) and output this value to the energization control section 26.

This action is performed every time the resistance value is sampled, and as a result, the resistance value of the drive member changes from a non-linearly changing region to a linearly changing resistance value, similar to the explanation in the first embodiment. is converted to

Then, the communication circuit 27 is turned on based on the arithmetic value input to the energization control section 26.

Therefore, it becomes possible to accurately control the driving member even in a non-curve changing region, and it becomes possible to set a large amount of curvature of the curved portion.

In this embodiment, an example using the A/D converter 55 has been described, but the same effect can be achieved by using, for example, a sample hold circuit instead of the A/D converter 55. It is.

FIG. 8 is a schematic configuration diagram of a system according to a third embodiment of the present invention.

In this actual airV/4, the endoscope 1 is configured as a video endoscope, and the distal end 6 provided on the distal end side of the insertion section 3 has an objective lens 28 that forms an image of the region to be observed. is provided, and a C0D 29 is fixed at the focal position of this objective lens 28.

Further, one end of a signal line 30 is connected to this C0D29, and the other end of the signal 830 is connected to the tip of this universal cord 5 via a universal cord 5 extending from one side of the operating section 4. Connector installed! ! It is fixed to @5a and the connector S! ! It is connected to a camera control unit (CCU>52 or a video processor) via the device 5a.

On the other hand, inside this CCIJ 52, there is an output signal generator 31.
．． A drive circuit 32 is provided, and when the clock signal generated by the clock signal generator 31 is input to the drive circuit 32, the drive circuit 32 generates the drive signal of the C0D29, and the signal line C0D through 30
29. The drive circuit 32
A set/horizontal transfer pulse generator 33 and a vertical transfer pulse generator 34 are provided within, and generate a reset pulse φH1 and a horizontal transfer pulse φV, respectively.

the above! 1! The direct transfer pulse φV is applied to the above C0D 29 via the signal line 30, while the reset/horizontal transfer pulse φR and the horizontal transfer pulse φH are applied to the drive condition control circuit 35.
The voltage is applied to the C0D29 through the above.

When the drive signal 8 from the drive circuit 32 is applied, the C0D 29 transmits the photoelectrically converted signal to the signal line 30.
The signal is input to the drive condition tiIII 111 circuit 35 through the drive condition circuit 35, and is also input to the process circuit 36 provided in the CCLJ 52. The pro-his circuit 36 takes in this signal, processes the video signal, and outputs it to the monitor 37.

Further, a light guide 38 for transmitting illumination light is disposed within the insertion portion 3. One end of this light guide 38 is fixed to the illumination through hole of the tip 6, while the other end is fixed to the connector fa5a, and the CCLI 52
The illumination light from the light source section 39 provided inside the tip section 6
t so that it can be transmitted to and irradiated to the area to be observed.
J is on.

In this embodiment, the curved portion 7 provided on the 11 end side of the distal end portion 6 is constructed by rotatably connecting a plurality of curved portions 42 to each other. A drive member 8 made of, for example, a shape memory alloy is built into the curved portion 7 . The drive member 8 expands and contracts in the axial direction to rotate the bending section 42 and bend the bending section 7. The driving member 8 is connected to the CCLJ via a signal line 30.
It is adapted to be connected to the curved a, II control section 40 disposed within the curved section 52. Further, a bias spring 41 is installed in the center of the curved portion 7 to bias the curved portion 7 into a straight line.

This bending control section 40 is configured in the same manner as the main part of the light source device explained in the first or second embodiment, and the energization control section (not shown) adjusts the intended bending angle or resistance. It is configured to calculate the curved portion from the resistance value of the driving member 8 detected by the value detection unit and output it to the process circuit 36, and the screen of the monitor 37 shows that the curved portion 7 is, for example, in an upward direction. If it is curved by 30 degrees, it will be displayed as "U30".

Further, the tip portion 6 is provided with an air/water supply nozzle 44,
An air/water channel 43 communicating with the air/water nozzle 44 is provided within the insertion portion 3 and the universal cord 5. Further, the operation unit 4 is provided with an air/water supply button 45 interposed in the middle of the air/water supply channel 43.

According to such a configuration, since the curved state and curved angle of the western bay 7 are displayed on the screen, there is an effect that the operability is improved by zero.

[Effects of the Invention] As explained above, in the endoscope device according to the present invention, when the electrical resistance value of the drive member changes non-linearly with respect to itJ degrees, the resistance value is transformed into logarithms and exponentials. Since the resistance value can be converted into a linear resistance value, the control range of the drive member is wide, and the curved portion of the curved portion can be set to a greater degree.

[Brief explanation of drawings]

1 to 5 relate to the first embodiment of the present invention, FIG. 1 is a schematic configuration diagram of the system, FIG. 2 is a 1099 diagram of the resistance value linearization unit detection circuit, and FIG. 3 is the resistance value A waveform diagram for explaining part of the operation of the linearization section detection circuit, FIG. 4 is a block diagram of the logarithmic/exponential conversion section, and FIG. 6 and 7 relate to a second embodiment of the present invention, in which FIG. 6 is a block diagram of a light source device, FIG. 7 is a waveform diagram of a voltage supplied to a driving member,
FIG. 8 is a schematic configuration diagram of a system according to a third embodiment of the present invention, and FIG. 9 is a characteristic diagram of electric resistance value with respect to temperature change of a driving member according to a conventional technique. 8... Drive member 10... Resistance value detection means 11... Resistance value detection section 12... Resistance value linearization section detection circuit 22... Logarithm/exponential conversion section (conversion means>26... Energization 1)
IIIti! Part 1 (till 1111 means) 27 ・ ・Electrification circuit (energization means) `` Figure 9 Temperature T Figure 3 (9) is Reimu 111-1-11 4 Figure 6 Figure 0 Figure 7 Figure rn dust jn + l scrap 3 = rn middle 23 (two

Claims (1)

[Scope of Claims] A driving member made of a heat-sensitive deformable member disposed in the insertion portion; energizing means for applying current to the driving member to bend the driving member; and an electrical resistance value of the driving member that is linear with respect to temperature. resistance value detection means capable of detecting an area where the resistance value changes non-linearly and an area where the resistance value changes non-linearly; and a control means capable of controlling the amount of current applied to the drive member by the energizing means based on the value converted by the converting means. An endoscope device featuring: