JP2003024276A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high heat sink effect in an endoscope having a light emitting element provided at a distal end of an insertion unit. SOLUTION: The endoscope comprises a printed circuit board 20 provided at the distal end of the insertion unit to mount two LEDs. A current is supplied through a shielded cable to the endoscope. The circuit board 20 has square lands 50A, 50K for mounting the first LED and square lands 51A, 51K for mounting the second LED. The land 50A in which an anode terminal of the first LED is mounted, is connected to a circular land 21 to which a core wire of the cable is connected, via a conductor pattern 22. The land 50K in which a cathode terminal of the first LED is mounted, is connected to the land 51A in which an anode terminal of the second LED is mounted, via a conductor pattern 23. A region except the conductor pattern 22 the lands 21 50A, 50K, the pattern 23, the lands 51A, 51K and an insulating region 24 for edging them is all formed as a conductor pattern GND for a ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat dissipation structure for a light source for illuminating an endoscope.

[0002]

2. Description of the Related Art In recent years, it has been proposed to provide an LED, which is a light source, at the tip of an insertion portion of an endoscope as the performance of a light emitting element such as a light emitting diode (LED) is improved. In such an endoscope, since the illumination light can be supplied to the observation site without passing through the light guide, it is easy to reduce the diameter of the endoscope insertion section and it is not necessary to provide a separate light source section. Therefore, the configuration can be simplified and downsized.

[0003]

FIG. 7 shows an example of a conventional portable endoscope to which the above configuration is applied. Endoscope body 100
Is generally composed of an elongated and flexible insertion section 110, an operation section 120 for performing an operation, and an eyepiece section 130 for performing an endoscopic observation. The image of the observation site is the insertion part 110.
The eyepiece lens provided in the eyepiece 130 is optically transmitted to the eyepiece 130 by the image guide (CFB) 150 composed of a bundle of ultrafine optical fibers through the objective lens 140 provided in the tip 110A of the Observed through 160. Further, a light source unit 170 including, for example, a plurality of LEDs is provided at the tip portion 110A, and the light emission of the LED is a current supplied from an LED drive circuit 180 provided in the operation unit 120 via a signal line 190. Controlled by.

By the way, the light-emitting characteristics of light-emitting elements such as LEDs have the characteristic that they deteriorate with increasing temperature. Further, since the distal end portion 110A of the endoscope has a small size and high airtightness, heat dissipation efficiency is poor. Therefore, when the LED is provided on the endoscope distal end portion 110A as described above, the LE and the like are generated due to heat generated from the LED as the lighting time elapses.
There is a problem that the temperature of D itself and its surroundings rises, and the spectral and light distribution characteristics of the illumination light deteriorate.

The present invention has been made to solve the above problems, and an object thereof is to provide an endoscope having a light emitting element at the tip of the insertion portion and a high heat dissipation effect.

[0006]

The endoscope of the present invention comprises at least one light emitting element as a light source for illumination, and a printed wiring board on which the light emitting element is mounted and which is arranged at the tip of the insertion portion of the endoscope. The surface of the printed wiring board is characterized in that a region other than a region occupied by a signal conductor pattern other than ground and an insulating region are formed as a ground conductor pattern.

In an endoscope, for example, a light emitting element is a light emitting diode, and a drive circuit for supplying a current for controlling light emission of the light emitting diode and a current from the drive circuit to a light emitting diode mounted on a printed wiring board. And a shielded cable for supplying the shielded portion of the shielded cable to the ground conductor pattern.
In addition, at least one cathode terminal of the light emitting diode is connected to the conductor pattern for ground, and the shielded cable has one signal line shielded by the shield part, and the current is supplied to only one signal line and the shielded line. Through the department. On the other hand, shielded cables are, for example,
It has two signal lines shielded by the shield part,
The current is supplied through the two signal lines. As a result, the heat escaping to the ground conductor pattern is further radiated through the shield portion of the shield cable and the signal line, and the heat radiation effect is further improved. Moreover, by using a shielded cable for power supply, the influence of external noise or radiated noise can be suppressed. Further, for example, at least one terminal of the light emitting element is connected to the ground conductor pattern. Thereby, the heat generated in the light emitting element can be more efficiently released to the ground conductor pattern.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment to which the present invention is applied.
It is a figure which shows the outline of a structure of the portable endoscope which is embodiment of this.

The endoscope body 10 is generally composed of an elongated and flexible insertion portion 11, an operation portion 12 for performing an operation, and an eyepiece portion 13 for performing an endoscope observation. The image of the observed portion is optically transmitted through the objective lens 14 provided at the tip portion 11A of the insertion portion 11 to the eyepiece portion 13 by the image guide (CFB) 15 formed of a bundle of ultrafine optical fibers.
To the eyepiece lens 16 provided in the eyepiece 13
Observed through. Further, the light source unit 17 including, for example, two LEDs 50 and 51 (see FIG. 2) as a light emitting element is provided on the tip portion 11A. The light emission of the LEDs 50 and 51 is performed by the LED drive circuit 1 provided in the operation unit 12.
It is controlled by the current supplied from 8 through the shielded cable 19. In addition to the image guide 15, inside the endoscope body 10, for example, a forceps channel, an air / water feeding channel, a suction channel, etc. are provided.
Although various operation buttons and the like are provided in 2, the illustration thereof is omitted.

FIG. 2 shows the electrical connection between the LEDs 50, 51 and the LED drive circuit 18. Figure 2
As shown in FIG.
0 and 51 are connected in series to the LED drive circuit 18. In addition, ON / OFF which controls driving / non-driving of the LED drive circuit 18 to control lighting / non-lighting of each LED.
Illustration of switches is omitted. The core wire 19A of the shielded cable 19 of FIG. 1 is connected to the anode terminal of the LED 50, and the shield portion 19K of FIG. 1 is connected to the cathode terminal of the LED 51.

FIG. 3 shows a conductor pattern of a printed wiring board on which the LEDs 50 and 51 are mounted. Printed wiring board 2
0 is formed into, for example, a substantially disc shape according to the shape of the tip portion 11A of the endoscope, and a circular opening 30 for inserting the objective lens 14 provided at the tip of the image guide 15 is provided in the center thereof. ing. On the printed wiring board 20, rectangular corner lands 50A, 50K, 51A, 51K for connecting anode terminals and cathode terminals of LEDs 50, 51 of surface mount type or the like are provided.
An anode terminal and a cathode terminal of the LED 50 are connected to the corner lands 50A and 50K, respectively.
The anode terminal and the cathode terminal of the LED 50 are connected to A and 51K, respectively. The square lands 50A and the square lands 51K, and the square lands 50K and the square lands 51A are arranged at positions substantially symmetrical with respect to a straight line that bisects the printed wiring board 20. The square land 50A is provided with the core wire 19A of the shielded cable 19 via the connecting portion 22 of the conductor pattern.
Is connected to the circular land 21 to which the square land 50 is connected.
K is a square land 51A via the connecting portion 23 of the conductor pattern.
Connected with.

On the printed wiring board 20, a region other than the region where the signal conductor pattern including the circular land 21, the square lands 50A, 50K, 51A and 51K and the connecting portions 22 and 23 is formed is substantially the entire surface ground conductor. Pattern G
It is covered with a conductive member as ND. That is, the circular land 21 excluding the corner land 51K, the corner land 50A, 5
The signal conductor pattern composed of 0K, 51A, and the connecting portions 22 and 23 is surrounded by the ground conductor pattern GND with the insulating region 24 (the white region in FIG. 3) surrounding the periphery of the signal conductor pattern GND sandwiched therebetween. Has been. Further, the corner ground 51K is formed integrally with the ground conductor pattern GND. The ground conductor pattern GND is connected to the shield portion 19K of the shield cable 19 and grounded.

As described above, in the first embodiment, the land for connecting the last cathode terminal of the LED connected in series is integrally formed with the ground conductor pattern of the printed wiring board, and the LED is also formed. An extremely wide ground conductor pattern can be obtained by forming the ground conductor pattern so as to surround the land portion to which the other electrode is attached and the signal conductor pattern connecting these. Since the signal conductor pattern and the ground conductor pattern, which are made of a conductive material, usually have high thermal conductivity, the heat generated in the LED and its surroundings can be efficiently transferred to the entire surface of the ground conductor pattern through the signal conductor pattern or the air. Can be conducted. The conductor pattern for ground is the shield part 1 of the shielded cable 15.
Since it is connected to 5K, the heat from the LED
It can escape to the heat conductive shield through the ground conductor pattern. Therefore, according to the first embodiment, a high heat dissipation effect can be obtained. Also, the LED has
Since power is supplied via the shielded cable 15,
At the same time, it is possible to suppress the influence of extraneous or radiation noise.

Next, a portable endoscope according to a second embodiment of the present invention will be described with reference to FIGS. Note that the same reference numerals are used for the components that perform the same functions as in the first embodiment.

FIG. 4 is a diagram schematically showing the configuration of the portable endoscope according to the second embodiment. The configuration of the portable endoscope in the second embodiment is substantially the same as the configuration of the portable endoscope in the first embodiment, except for the shape of the conductor pattern of the printed wiring board to which the LED is attached and the LE.
It is a structure of a shielded cable for supplying electric power from the D drive circuit to the LED. Hereinafter, only parts different in shape and structure from the first embodiment will be described.

A light source unit 17 'is provided at the distal end portion 11A of the endoscope.
Is provided, and the light source unit 17 ′ is connected to the LED drive circuit 18 by the shield cable 40. In the shielded cable 40, there are 2
The signal lines 40A and 40K of the book are provided, and the current is an LED provided in the light source unit 17 ′ through these signal lines.
It is supplied to 50 and 51.

FIG. 5 shows the electrical connection between the LEDs 50 and 51 and the LED drive circuit 18. Figure 5
As shown in, the LED 5 provided in the light source unit 17 '
0 and 51 are connected in series to the LED drive circuit 18. In addition, ON / OFF which controls driving / non-driving of the LED drive circuit 18 to control lighting / non-lighting of each LED.
Illustration of switches is omitted. Shielded cable 4 in Figure 4
The signal line 40A of 0 is connected to the anode terminal of the LED 50, and the signal line 40K is connected to the cathode terminal of the LED 51.

FIG. 6 shows a conductor pattern of a printed wiring board on which the LEDs 50 and 51 are mounted. Printed wiring board 2
0'is the tip portion 11A of the endoscope as in the first embodiment.
A circular opening 30 for inserting the objective lens 14 provided at the tip of the image guide 15 is provided in the center of the image guide 15, for example.
On the printed wiring board 20 ', a square land 50 for connecting the anode terminal and the cathode terminal of the LEDs 50, 51.
A, 50K, 51A and 51K 'are provided. The arrangement of the square lands 50A, 50K, 51A, 51K 'is the first
If the square land 51K in the above embodiment is read as 51K ′, it is the same as in the first embodiment.

The square land 50A is a connecting portion 2 of the conductor pattern.
2 is connected to the circular land 21 to which the signal line 40A of the shielded cable 40 is connected, and the square land 50K is connected to the square land 51A via the connecting portion 23 of the conductor pattern. Further, the square land 51K ′ to which the cathode terminal of the LED 51 is connected is connected to the circular land 25 to which the signal line 40K of the shield cable 40 is connected via the connecting portion 26 of the conductor pattern.

On the printed wiring board 20 ', square lands 50A, 50K, 51A, 51K', circular lands 2
Areas other than the area where the signal conductor pattern composed of 1, 25 and the connecting portions 22, 23, 26 are formed are covered with a conductive member as a ground conductor pattern GND ′. That is, the corner lands 50A, 50K, 51A, 51
K ', circular lands 21, 25, connecting portions 22, 23, 26
The signal conductor pattern consisting of and is surrounded by the ground conductor pattern GND ′ with the insulating region 24 ′ (the white region in FIG. 6) surrounding the periphery thereof sandwiched. The ground conductor pattern GND ′ is connected to the shield portion 40G of the shield cable 40 of FIG. 4 and is grounded.

As described above, also in the second embodiment, the same effect as that of the first embodiment can be obtained.

Although the number of LEDs is two in the present embodiment, the number of LEDs is not limited to this, and may be larger or smaller than this. Also LED
The arrangement of is also not limited to the arrangement of this embodiment.

In the present embodiment, the portable endoscope has been described as an example, but it goes without saying that the application of the present invention is not limited to the portable endoscope, and a normal fiberscope or an electronic endoscope is used. You may use for the electronic scope in an endoscope apparatus.

[0024]

As described above, according to the present invention, a high heat dissipation effect can be obtained in an endoscope in which a light emitting element is provided at the tip of the insertion portion.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a portable endoscope of a first embodiment to which the present invention is applied.

FIG. 2 is a diagram schematically showing the electrical configuration of an LED provided at the tip of the endoscope in the first embodiment.

FIG. 3 is a diagram showing a conductor pattern of a printed wiring board on which LEDs are mounted in the first embodiment.

FIG. 4 is a schematic view of a portable endoscope of a second embodiment to which the present invention is applied.

FIG. 5 is a diagram schematically showing the electrical configuration of an LED provided at the distal end portion of the endoscope according to the second embodiment.

FIG. 6 is a diagram showing a conductor pattern of a printed wiring board on which LEDs are mounted in the second embodiment.

FIG. 7 is a diagram showing an example of a conventional portable endoscope in which an LED is provided at the tip of the endoscope.

[Explanation of symbols]

10 endoscope 11 Insert 11A tip 17 Light source 19, 40 shielded cable 20, 20 'printed wiring board 21, 25 circular land 50A, 50K, 51A, 51K, 51K 'Square land 50, 51 LED GND, GND 'Ground conductor pattern

Claims (5)

[Claims] 1. A light source for illumination, comprising at least one light emitting element, and a printed wiring board on which the light emitting element is mounted and arranged at a tip of an insertion portion of an endoscope. An endoscope characterized in that a region other than the signal conductor pattern other than the above and a region excluding the insulating region are formed as a ground conductor pattern. 2. The light emitting element is a light emitting diode,
A drive circuit for supplying a current for the endoscope to further control the light emission of the light emitting diode; and a shielded cable for supplying the current from the drive circuit to the light emitting diode mounted on the printed wiring board. The endoscope according to claim 1, further comprising: a shield portion of the shield cable, the shield portion being connected to the ground conductor pattern. 3. At least one cathode terminal of the light emitting diode is connected to a ground conductor pattern, and the shielded cable has one signal line shielded by the shield part, and the current is supplied to the shielded cable. The endoscope according to claim 2, wherein the operation is performed via the one signal line and the shield part. 4. The shielded cable has two signal lines shielded by the shield portion, and the current is supplied through the two signal lines. The described endoscope. 5. The endoscope according to claim 1, wherein at least one terminal of the light emitting element is connected to a ground conductor pattern.