JPH0260326B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in endoscopes using solid-state imaging devices.

Endoscopes that use optical fibers have been known for some time, but in order to obtain good images, the number of pixels in the fiber must be increased, and the thickness of the fiber becomes thicker. The fibers have considerable rigidity, and there is a risk of damaging the fibers when bent, requiring advanced insertion techniques when inserting into small areas or curved parts, which has the disadvantage of being difficult to insert. In particular, when inserted into a living body, it causes great pain to the patient and is also dangerous.

In order to solve the above-mentioned drawbacks, it is conceivable to provide a solid-state image pickup device in a viewing head and to connect the viewing head and an external device electrically through lead wires. However, in such cases, the electric lead wire has the disadvantage that it is difficult to successfully insert the viewing head into the target site due to insufficient rigidity.

In view of these points, the present invention provides an endoscope using a solid-state image sensor, in which the observation head containing the solid-state image sensor is made into a capsule shape, and a self-propelled device is provided in the head, so that the observation head can move on its own. , it is characterized by having a configuration that allows it to reach the target site.

Hereinafter, the prior art of the invention and the embodiments of the invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram of an endoscope according to the prior art in which an observation head is provided with a self-propelled device using a caterpillar. The festival head 1 is provided with an imaging lens 2, a solid-state imaging device 3, an illumination lamp 4, and a caterpillar drive mechanism 6. The caterpillar drive mechanism 6 is
The worm gear 7 is rotated by the motor M, which is stopped by a remote control from the outside, and the gear 9 is rotated via the gear 8. The caterpillar drive wheel fixed coaxially to the gear 9 is rotated, and the caterpillar drive wheel is fixed to the gear 9 coaxially. 12 is driven. Festival head and external equipment (not shown)
A lead wire for lighting an illumination lamp, a lead wire for transmitting an imaging signal, and a lead wire for driving a motor are arranged inside the insertion portion 5 between the two. Incidentally, an air supply hole, a water supply hole, a forceps introduction hole, etc. may be provided inside the insertion portion 5 as necessary, and the structure may be such that necessary treatment can be performed. Further, as shown in FIG. 2, the treatment instrument tube 13 may be configured with an air supply hole, a water supply hole, a forceps introduction hole, etc., and the insertion section 5 may be guided as a fixation rope, and the observation head By guiding the tube with the treatment tool after the patient reaches the target site and confirms the affected area, the treatment tool can be reliably inserted to the target site without causing much pain to the patient.

FIG. 3 is a diagram showing an embodiment of an endoscope provided with a self-propelled device constructed using a well-known shape memory alloy according to the present invention. FIG. 3a is a schematic side view showing a state in which the legs made of shape memory alloy provided on the observation head are contracted, FIG. 3b is a schematic side view showing the state in which the legs are extended, and FIG. c is Figure 3a
FIG. 3 is a schematic front view of the state shown in FIG.

Inside the observation head 1, heaters H1 to _H4 are provided for applying heat to the imaging lens 2, solid-state image sensor 3, illumination lamp 4, and _{legs L1} to _L4 made of shape memory alloy. . A sensor S ₀ for detecting the front condition is provided at the front end of the head, and sensors S ₁ to S ₄ for detecting the lateral condition are provided on the side surfaces.
A FET pressure sensor or the like can be used as the sensor, and at least one sensor is provided at the front end and four sensors are provided at the side surface. Further, on the side surface of the festival head 1, there are provided legs _L1 to _L4 made of shape memory alloy for running the head.
The legs L ₁ to _{L 4} are heated by the heaters H ₁ to _{H 4} and when they reach a certain temperature, they change from the contracted state shown in FIG. 3a to the state shown in FIG. 3b. extend. This traveling device is controlled and operated by a control mechanism whose block diagram is shown in FIG. The operating state of the above embodiment will be explained below. When the observation head 1 is in the straight traveling section as shown in FIG. 5, the sensor _S0 at the tip of the head does not detect pressure, but the sensors _S1 to _S4 on the sides detect pressure from the wall surface. The signal from the sensor is transmitted to the controller 14, and the controller 14 determines that the head should move straight in the direction A based on the signal, and turns the heater on.
All of H ₁ to _{H 4} are actuated, all legs L ₁ to _{L 4} are extended, and the observation head 1 moves straight in the A direction. Next, when the observation head 1 is at a bend as shown in FIG. 6, the front sensor S ₀ and the side sensors S ₁ ,
S ₂ and S ₄ detect pressure, but sensor S ₃ on the side does not detect pressure. When this signal is transmitted to the controller 14, the controller 14 determines that the observation head 1 should move in the direction B, operates only the heater _H1 , extends the leg _L1 , and moves the observation head 1 in the direction B. Proceed in the direction.
Note that the controller 14 stops the operation of the heater after detecting that the heater has been activated, and after detecting that the temperature of the heater has decreased, causes the observation head 1 to repeatedly perform the above-described traveling operation. The robot moves on its own and reaches its destination.

In this embodiment, there is no need to provide a power member such as a motor or a gear, or a power transmission member within the observation head.
Since only the heater needs to be installed inside the observation head,
A self-propelled device can be created with a simple configuration, and the observation head can be downsized. Further, the traveling direction of the observation head can be controlled by a simple configuration in which a sensor is provided and a heater is selectively activated, and the observation head can be easily and reliably inserted into a bent area.

It goes without saying that in this embodiment as well, the insertion section 5 can be constructed as a fixation rope to guide the tube with the treatment instrument.

FIG. 7 is a diagram showing another embodiment of a self-propelled device using a shape memory alloy. In this embodiment, a running member 15 is slidably provided on the side surface of the viewing head 1, a shape memory alloy 16 is connected to an end inside the head, and the other end of the shape memory alloy 16 is installed inside the viewing head 1. The heater 17 is fixed to a heater 17 which is controlled by an external controller (not shown). To explain the operating state of this embodiment, when the heater 17 is not operating and the temperature is low, the shape memory alloy 16 is contracted as shown in FIG. being brought in. When the heater is activated and reaches a certain temperature, the shape memory alloy 16 expands and the traveling member 15 is pushed out of the observation head 1, as shown in FIG. When this happens, the festival head 1 moves forward. In this embodiment as well, the traveling direction of the observation head can be controlled by providing a sensor in the observation head and controlling the heater.

FIG. 8 is also a diagram showing another example in which a self-propelled device is constructed using a shape memory alloy.

In this embodiment, an observation head guide member 6 is provided outside the observation head 1, and the observation head 1 and the observation head guide member 6 are connected by a shape memory alloy 19. A blocking member 21 made of a shape memory alloy is provided at the rear of the observation head. Heaters 20 and 22 are provided inside the observation head and are operated under the control of an external controller (not shown). The heater 20 is a heater for operating the shape memory alloy connecting the observation head 1 and the observation head guide member 6, and the heater 22 is a heater for operating the blocking member 21. The operating state of this embodiment will be explained below. When the heaters 20 and 22 are not operating,
The shape memory alloy 19 and the blocking member 21 have shrunk,
As shown in FIG. 8a, the observation head 1 is housed in an observation head guide member 18. As shown in FIG. In this state, first, the heater 22 is activated, and the blocking member 21 extends and comes into contact with the wall surface of the traveling area, thereby preventing the observation head 1 from retreating. Next, the heater 20 is activated, and the shape memory alloy 19 expands to push the observation head guide member 18 forward (the state shown in FIG. 8b). After this, the operation of the heater 20 is stopped, the blocking member 6 is retracted, the operation of the heater 20 is stopped, the shape memory alloy 8 is retracted, and the observation head 1 is moved to the observation head guide member 6.
Move forward so that it is stored inside. By repeating the above operations, the observation head 1 moves by itself and reaches the target site.

As described above, the present invention is constructed by using a capsule-type observation head with a built-in solid-state image sensor and a self-propelled device installed in the head. The observation head can be inserted easily and reliably.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of an endoscope with a self-propelled device using a caterpillar in the viewing head, and Fig. 2 is a schematic diagram of an endoscope with a fixation tube in the insertion section, and a treatment tool equipped with an air supply hole, water supply hole, forceps introduction hole, etc. Figures 3a, b, and c are schematic diagrams of an endoscope configured to guide a tube; The figure is a block diagram of the control mechanism of the self-propelled endoscope shown in FIG. 3, and FIGS. Figures 7a and b are schematic diagrams showing other embodiments in which a self-propelled device is constructed using a shape memory alloy, and Figures 8a and b are also schematic diagrams showing other embodiments in which a self-propelled device is constructed using a shape memory alloy. FIG. 2 is a schematic diagram illustrating an example. 1...Observation head, 2...Imaging lens, 3...
Solid-state image sensor, 4... Illumination lamp, 5... Insertion section, 12... Caterpillar, 13... Tube with treatment tool,
L ₁ ~ L ₄ ... Legs made of shape memory alloy, H ₁ ~ _{H 4} ...
...Heater, _S0 to _S4 ...Sensor, 14...Controller,
15... Running member, 16... Shape memory alloy, 17
... Heater, 18 ... Observation head guide member, 19
... Shape memory alloy, 20 ... Heater, 21 ... Blocking member made of shape memory alloy, 22 ... Heater.

Claims (1)

[Claims] 1. A capsule-shaped observation head containing a solid-state image sensor, a plurality of sensors provided on the outer periphery of the observation head, a plurality of self-propelled devices including a shape memory alloy and a heater provided on the outer periphery of the observation head, and An endoscope using a solid-state image sensor, characterized in that the endoscope includes a control means for selectively heating the heaters of the plurality of self-propelled devices based on the output of the sensor.