JP6055617B2 - Endoscope device - Google Patents

Description

  The present invention relates to an endoscope apparatus that images a subject such as an inner wall of an organ, and more particularly, to a cooling mechanism at the distal end portion of the endoscope.

  In an electronic endoscope apparatus, an imaging module including an image sensor (imaging device) and a circuit board is provided at the distal end of a video scope, and an observation image is generated based on a pixel signal read from the image sensor, and is monitored. Etc.

  The heat generated in the imaging module during endoscopic work causes the generation of image noise. As a method for preventing this, it may be possible to dissipate heat by disposing a Peltier cooling element on the side surface of the imaging module (see, for example, Patent Document 1). The Peltier element employs a flat and square structure in which N-type and P-type semiconductors are alternately connected in series between the heat dissipation surface and the heat absorption surface.

  Various electronic components such as capacitors are disposed on the substrate of the imaging module, and a large number of wires extend along the endoscope axis direction. Therefore, it is difficult to mount the Peltier element as it is on the back side of the imaging module at the endoscope front end portion where the space is small. In order to avoid this, a configuration has been proposed in which an extending portion extending in the axial direction is formed with respect to the substrate of the imaging module, and a Peltier element is disposed on the side surface thereof (see Reference 2).

JP 2010-22815 A JP 2010-35815 A

  In the cooling structure in which the planar type and the square type are arranged on a part of the side surface of the substrate, heat can be absorbed only from the side surface of the substrate, and heat generated in the entire substrate cannot be absorbed effectively.

  In order to improve the cooling function with such a structure, it is necessary to stack them due to the structure. However, it is difficult to stack a thick planar Peltier cooling element on the distal end portion of the endoscope having a limited arrangement space.

  Therefore, a Peltier element that has an excellent cooling function and can be easily mounted on the distal end portion of the endoscope is required.

  The endoscope according to the present invention is disposed on the back surface side of the image sensor, the substrate on which the image sensor is disposed, the heat absorbing portion is formed on the inner peripheral surface side, and the heat radiating portion is formed on the outer peripheral surface side. And a cylindrical Peltier element. The Peltier element is arranged so that one end surface thereof faces the back surface of the substrate. For example, the Peltier element can be formed in a cylindrical shape.

  The heat generated in the imaging module is easily transferred from the back side of the substrate on which the element is mounted toward the opposite side of the tip (the processor side). The Peltier element is installed such that the end surface thereof faces the back side of the substrate in the axial direction of the endoscope distal end portion or in the direction along the optical axis direction of the objective optical system disposed at the distal end portion.

  Therefore, when heat is transmitted to the hollow portion, the heat moves from the inner peripheral surface acting as the heat absorbing portion toward the outer peripheral surface acting as the heat radiating portion, and the Peltier element diffuses the heat radially. As a result, the heat generated in the imaging module can be released uniformly on the rear side.

  The substrate can be provided with a heat conductive portion extending from the back surface of the substrate in the hollow portion of the Peltier element. For example, a casing member that covers the wiring extending from the substrate can be configured as a hollow member, and can function as a wiring cover and a heat transfer member that secure a wiring path.

  In consideration of efficiently transporting heat from the thermally conductive portion to the Peltier element, it is possible to adopt a configuration in which the thermally conductive portion and the Peltier element are brought into contact with each other. For example, a heat conductive part can be fitted and adhered to the Peltier element.

  The Peltier element and the back surface of the substrate may or may not be contacted. Considering preventing heat from moving directly from the substrate along the axial direction and from the Peltier element to the substrate, the heat sink is brought into contact with the back surface of the substrate at one end surface, while the heat sink is It is better not to contact the back side of the substrate.

  As a structure of the Peltier element, an inner cylinder as a heat absorbing plate and an outer cylinder as a heat sink may be provided, and a plurality of P-type semiconductors and a plurality of N-type semiconductors may be connected in series therebetween. It is also possible to configure a wiring with only + and -2 terminals, and this can be realized by arranging a plurality of P-type semiconductors and a plurality of N-type semiconductors alternately in a spiral shape along the axial direction of the element. is there.

  In consideration of more effective heat dissipation from the Peltier element, it is possible to provide a cylindrical heat dissipation member that covers the Peltier element.

  The Peltier cooling element in another aspect of the present invention can be applied to an imaging module that can be incorporated into an endoscope, a probe, or other small-diameter scope, and has an inner cylindrical body having thermal conductivity, and thermal conductivity, A plurality of P-type semiconductors and a plurality of N-type semiconductors which are alternately arranged in a spiral shape along the axial direction between the outer cylinder covering the inner cylinder and the inner cylinder and the outer cylinder and connected in series And the heat dissipating part and the heat absorbing part are formed in the inner cylinder and the outer cylinder.

  The imaging module includes an imaging device and a substrate on which the imaging device is installed, and the substrate has a thermally conductive portion that extends from the back surface of the substrate in the hollow portion of the Peltier device.

  As described above, according to the present invention, it is possible to effectively cool the distal end portion of the endoscope having a limited space.

It is a block diagram of the video scope (endoscope) of the electronic endoscope apparatus which is this embodiment. It is the perspective view which showed the structure of the imaging module and the Peltier device. It is a top view of a Peltier device. It is the figure which showed typically the semiconductor arrangement configuration inside a Peltier device.

  Hereinafter, the electronic endoscope apparatus according to the present embodiment will be described with reference to the drawings.

  FIG. 1 is a block diagram of a video scope (endoscope) of the electronic endoscope apparatus according to the present embodiment.

  The video scope 10 can be detachably connected to a processor (not shown), and includes an imaging module 20 at the distal end portion 10T. A light guide (not shown) provided in the video scope 10 transmits illumination light from a light source unit provided in the processor to an observation site.

  The imaging module 20 includes an imaging element 21 such as a CCD or CMOS and a substrate 22, and an electronic component such as a capacitor is installed on the substrate 22 together with the imaging element 21. The light reflected by the subject passes through the objective lens 23 and forms an image on the light receiving surface of the image sensor 21. Thereby, a pixel signal generated in the image sensor 21 is transmitted to a processor (not shown) via a signal cable 50 connected to the substrate 22.

  The substrate 22 includes a rectangular substrate body 22A on which an image sensor is mounted, and a cylindrical casing portion 22B protruding from the back surface side of the substrate body 22A. A cylindrical Peltier element 30 is disposed around the casing portion 22 </ b> B, and a cylindrical heat dissipation member 40 made of metal or the like is disposed around the Peltier element 30.

  FIG. 2 is a perspective view illustrating the configuration of the imaging module 20 and the Peltier element 30. However, the heat dissipation member 40 is not shown here.

  The substrate 22 is configured as a ceramic substrate having a cylindrical casing portion 22B attached to the back surface of the substrate body 22A, and is a package module integrated with the image sensor 21. Various wirings C such as a power supply line and a signal line extend from one end 22C side of the casing part 22B, and these wirings CL constitute the signal cable 50. The casing portion 22B is formed in a cylindrical shape so as to allow the wiring CL to pass therethrough, and covers the wiring CL to ensure a wiring path.

  An end surface 30A of the Peltier element 30 that faces the back surface 22S of the substrate body 22A faces the substrate body 22, and its axial direction is substantially along the endoscope axis direction and the optical axis of the objective lens 23. The cylindrical Peltier element 30 is mounted so that the casing part 22B fits into the hollow part 30T, and the casing part 22B and the entire inner peripheral surface of the Peltier element 30 are in close contact with each other. When electric power (not shown) is supplied, the Peltier element 30 operates so as to release heat generated in the imaging module 20 to the surroundings.

  Next, the internal structure of the Peltier element according to this embodiment will be described with reference to FIGS. FIG. 3 is a plan view of the Peltier element 30. FIG. 4 is a diagram schematically showing a semiconductor arrangement configuration inside the Peltier element.

  The Peltier element 30 includes an inner cylindrical heat absorbing plate 32A that is in close contact with the casing portion 22B of the substrate 22 and a cylindrical heat radiating plate 32B that covers the heat absorbing plate 32A, and a plurality of N-type semiconductors T1 and P-type are interposed therebetween. The semiconductors T2 are regularly arranged. The heat absorbing plate 32A and the heat radiating plate 32B are made of a material such as a metal having high thermal conductivity.

  The plurality of N-type semiconductors T1 and P-type semiconductors T2 are alternately arranged in a spiral shape with respect to the direction of the axis C of the Peltier element 30, and are formed on the thin film electrodes L formed along the inner surfaces of the heat absorbing plate 32A and the heat radiating plate 32B. Are connected in series. 3 shows a part of the semiconductor arrangement when viewed from the end face 30A of the Peltier element 30, and FIG. 4 shows a helical arrangement of the N-type semiconductor T1 and the P-type semiconductor T2.

  The cylindrical heat absorbing plate 32A is formed with a connecting portion 32T projecting along the axial direction C from the heat radiating plate 32B on one end face side, and is in close contact with the substrate body 22A. On the other hand, the heat sink 32B is not in contact with the substrate body 22A.

  By inserting and fitting the casing portion 22B into the hollow portion 30T of the Peltier element 30 having such a semiconductor helical series arrangement structure, a heat dissipation action is exerted.

  More specifically, since the casing portion 22B has thermal conductivity, heat generated in the image sensor 21 and the substrate body 22A during the endoscopic operation is transmitted to the casing portion 22B, and the wiring CL extends. It is transmitted to the internal space and moves toward the casing end 22C.

  The Peltier element 30 operates so that its inner peripheral surface (heat-absorbing plate 32A) is a heat-absorbing part and outer peripheral surface (heat-dissipating plate 32B) is a heat-generating part. Therefore, the heat transmitted to the casing part 22B is transmitted to the Peltier element 30. It is absorbed and emitted radially from the entire outer peripheral surface of the Peltier element 30. Further, heat is released from the entire heat radiating member 40 by the heat radiating member 40 in close contact with the Peltier element 30.

  As described above, according to the present embodiment, the imaging module 20 including the imaging element 21 and the substrate 22 is arranged at the distal end portion of the endoscope, and the cylindrical Peltier element 30 is disposed on the rear side of the substrate opposite to the distal end portion. Is placed. And the casing part 22B which covers the wiring CL extended from the board | substrate main body 22A is fitted and closely_contact | adhered to the hollow part 30T of the Peltier element 30. FIG. Thereby, the heat generated from the imaging element 21 and the substrate 22 moves to the rear side of the substrate and is diffused in the radial direction through the heat radiating member 40 at the distal end portion of the endoscope.

  A cylindrical Peltier element 30 is constructed instead of a conventional square Peltier element, and a heat-conductive substrate casing 22B is fitted into the hollow part 30T of the Peltier element 30 to provide a sufficient heat dissipation surface in a small space. Can be secured, and the cooling effect is enhanced.

  In particular, since the casing portion 22B serves both as a wiring cover and heat transfer, a small cooling mechanism that does not waste space is realized. In addition, in order to effectively transfer heat along the video scope axis direction on the back side of the substrate, it is possible to prevent the heat from diffusing to the distal end side of the endoscope, that is, the subject side, and to reduce the influence of heat on the human body Can do.

  Furthermore, since the casing portion 22B and the Peltier element 30 are in close contact, and the Peltier element 30 and the heat dissipation member 40 are in close contact, heat is quickly diffused radially, and heat is prevented from accumulating at the distal end portion of the endoscope. On the other hand, since only the heat absorbing plate 32A contacts the substrate body 22A, the Peltier element 30 prevents heat from being transferred from the heat radiating plate 32B to the substrate 22 again.

  Further, since the alternate series connection of the N-type semiconductor T1 and the P-type semiconductor T2 provided in the Peltier element 30 is spiral, all the N-type semiconductor T1 and P-type semiconductor T2 are formed by only one set of + and − terminals. Can be operated.

  In addition, when incorporating the image sensor module into the endoscope tip, it is only necessary to make a round hole in the endoscope tip according to the size of the heat dissipating member. Can be implemented.

  The shape of the Peltier element does not have to be strictly cylindrical as long as it is cylindrical. As for the semiconductor arrangement, it is also possible to form a cylindrical Peltier element by hierarchizing a planar module in which N-type semiconductors and P-type semiconductors are two-dimensionally arranged and connected in series like a planar Peltier element. is there.

  The Peltier element is in close contact with the substrate body and the casing part, but it is also possible to make partial contact with each other, or it is possible to prevent the Peltier element from contacting the substrate body and the casing part. Furthermore, it is also possible to employ a configuration in which the casing portion is not provided, and heat transmitted from the substrate to the hollow portion of the Peltier element can be absorbed and diffused from the outer peripheral surface. Moreover, it is also possible to employ a configuration in which no heat dissipation member is provided due to space limitations.

10 Videoscope (endoscope)
20 Imaging module 21 Imaging element 22 Substrate 22A Substrate body 22B Casing (thermally conductive portion)
22S Substrate back surface 30 Peltier element 30A One end surface 30T Hollow portion 32A Endothermic plate (inner cylinder, endothermic portion)
32B heat sink (outer cylinder, heat sink)
32T connection part 40 heat dissipation member 50 signal cable CL wiring T1 N-type semiconductor T2 P-type semiconductor

Claims (7)

An image sensor;
A substrate on which the image sensor is installed;
A cylindrical Peltier element disposed on the back side of the substrate, forming a heat absorbing portion on the inner peripheral surface side, and forming a heat radiating portion on the outer peripheral surface side;
It said Peltier element, and a back surface of the substrate and its one end face are disposed so as to face,
The endoscope according to claim 1, wherein the heat absorbing portion arranged to face the back surface of the substrate is in contact with the back surface of the substrate . The endoscope according to claim 1, wherein the substrate has a heat conductive portion extending from a back surface of the substrate in a hollow portion of the Peltier element. Have a casing which covers the wirings extending from the front Stories substrate endoscope according to claim 1 or 2, wherein the Peltier element is characterized in that for covering the casing portion. The endoscope according to any one of claims 1 to 3, wherein the imaging element, the substrate, and the Peltier element are provided at a distal end portion of the endoscope. Before SL radiating portion, endoscope according to any one of claims 1 to 4, characterized in that not in contact with the substrate. An image sensor;
A substrate on which the image sensor is installed;
A cylindrical Peltier element disposed on the back side of the substrate, forming a heat absorbing portion on the inner peripheral surface side, and forming a heat radiating portion on the outer peripheral surface side;
The Peltier device, contact the back surface of the substrate and its one end face is arranged so as to face
The
The Peltier element has an inner cylinder as a heat absorbing plate, an outer cylinder as a heat sink, a plurality of P-type semiconductors and a plurality of N-type semiconductors provided between the inner cylinder and the outer cylinder. And
Endoscope plurality of P-type semiconductor and a plurality of N-type semiconductor are arranged spirally alternately along the axial direction, and you characterized in that connected in series.   The endoscope according to any one of claims 1 to 6, further comprising a cylindrical heat dissipation member that covers the Peltier element.

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