JP2598568C - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electronic device provided with means for reducing emission of unnecessary radiation noise and noise mixing.
The present invention relates to an endoscope device. [Prior art] In recent years, by inserting an elongated insertion portion into a body cavity to observe organs in the body cavity, etc.
If necessary, various treatments can be performed using the treatment tool inserted into the treatment tool channel.
Kiri endoscopes are widely used. In addition, a solid-state imaging device such as a charge-coupled device (CCD) as an imaging means is provided at the tip of the insertion portion.
An electronic endoscope with a device that takes out image information as an electrical signal obtained by photoelectric conversion
Have also been proposed. By the way, in the case of a medical electronic endoscope, a circuit part (patient
Circuit) and the circuit section (secondary circuit) connected to peripheral devices such as monitors
In order to secure the isolation means, for example, as disclosed in Japanese Patent Application Laid-Open No. 1-223928,
Insulated. In other words, if insulation is not provided by the isolation means, if insulation with respect to GND is reduced or defective due to a failure or the like, GN is passed through the human body with the endoscope inserted.
A current is expected to flow through D, and a very dangerous situation is expected. In contrast
When the patient circuit and the secondary circuit are insulated by the isolation means,
Even if the insulation is reduced, the current flows to GND on only one circuit side.
Nature can be secured. For example, if the current flows only on the patient circuit side,
Has a small effect on Also, if the current flows only on the secondary circuit side, the patient circuit side is disconnected.
The patient is safe because of the margin. [Problems to be Solved by the Invention] However, due to the above-mentioned isolation means, the G between the patient circuit and the secondary circuit is reduced.
Since the ND is not shared, signals are radiated as radio waves to the outside of the device via stray capacitance and the like.
It is easy to be radiated, and external radio waves may enter the device through stray capacitance.
It becomes easy to perform. For example, electric signals used in an electronic endoscope device are radiated to other electronic devices,
There is a possibility that noise may cause malfunction. In addition, noise radiated from other electronic devices
Noise easily mixes into the electronic endoscope device.
If the quality of the endoscope image deteriorates or noise is mixed in the control signal, it may cause malfunction.
Would. In general, various signals having different levels are handled in the electronic endoscope device.
To minimize unnecessary radiation noise and mix radiation noise.
It is desired to have a function capable of suppressing the occurrence of the blemishes as much as possible. Recently, EMC (electromagnetic interference problem) has been applied to general electric equipment.
EMI) and the problem of electromagnetic interference (EMS))
Is increasingly desired. The present invention has been made in view of the above points, and has been described in consideration of generation of unnecessary radiation noise.
Provide an electronic endoscope device that can sufficiently suppress or reduce unwanted radiation noise contamination.
The purpose is to provide. [Means for Solving the Problems and Action] An electronic endoscope according to the present invention is an electronic endoscope having a built-in image sensor that can be inserted into a body cavity or the like.
An endoscope, a patient circuit connected to the electronic endoscope for processing an output signal from the imaging device, and an output signal from the imaging device processed by at least the patient circuit
Is transmitted through the electrical insulation means and the transmitted signal is processed at the second time.
And the electronic endoscope of the conductive portion that is the reference potential of the patient circuit.
A connector receiving portion to which a connector is connected and a conductive portion which is a reference potential of the secondary circuit
A capacitor for connecting a portion of the chassis which is to be the ground of the secondary circuit
Are provided. EXAMPLES Hereinafter, the present invention will be described specifically with reference to the drawings. 1 to 15 relate to a first embodiment of the present invention, and FIG.
FIG. 2 is a block diagram showing the configuration of the signal processing system of the camera control unit.
FIG. 3 is a circuit diagram of an isolation circuit, and FIG. 4 is a configuration of an electronic scope.
FIG. 5 is a sectional view taken along the line AA ′ of FIG. 4, and FIG. 6 is a schematic structure of the cable connector.
FIG. 7 is an explanatory view showing an enlarged part of FIG. 6, and FIG. 8 is a camera.
FIG. 9 is a perspective view schematically showing a connector receiver provided in the control unit.
8 is a perspective view showing the back side, FIG. 10 is an explanatory view showing a part of FIG. 1, and FIG.
Indicates that both GND of the patient circuit and the secondary circuit are connected by a capacitor
FIG. 12 is a perspective view showing the shield case, and FIG. 13 is an enlarged view of a part of FIG.
FIG. 14 is an explanatory view showing a drain opening, and FIG.
It is a perspective view which shows the connection part with a source. As shown in FIG. 1, the electronic endoscope apparatus 1 according to the first embodiment has an electronic
A light source device 3 for supplying illumination light to the electronic scope 2;
A video processor or camera control unit that performs signal processing on
(Hereinafter abbreviated as CCU) 4 and a signal processed by this CCU 4.
A TV monitor 5 for displaying a standard video signal and a TV monitor connected to the CCU 4
Keyboard for inputting data such as comments on the endoscope image displayed on
6. The electronic scope 2 can be inserted into a body cavity as shown in FIG. 1 or FIG.
A wide operating section 9 is formed at the rear end (base end) of the elongated insertion section 8 having flexibility.
The universal cable 11 is extended from the operation unit 9 to the outside. At the end of the universal cable 11, a light source connector 12 is attached.
The light source 12 can be detachably mounted on the light source device 3. A light for transmitting illumination light is provided in the insertion portion 8 and the universal cable 11.
When the guide 13 is inserted and the connector 12 is mounted on the light source device 3, the light source
The illumination light of the lamp 14 in the device 3 passes through the aperture 15 and is collected by the lens 16.
Irradiates the end face of the opposing light guide 13. This light guide 13
The transmitted illumination light is directed forward from the other end face attached to the distal end portion 17 of the insertion portion 8.
It is emitted and illuminates a subject such as an affected part. The illuminated subject is provided at the tip 17
CCD 1 as a solid-state imaging device disposed on the focal plane by the objective lens 18
9 is formed on the imaging surface 9. A mosaic filter for color separation is provided on the imaging surface of the CCD 19.
Filter 19a, for example, optically color-separated for each pixel,
The signal is photoelectrically converted by D19, converted into an electric signal, and stored as electric charge. this
The CCD 19 receives the drive signal inserted through the insertion section 8 and the universal cable 11.
Signal transmission line 21a and one end of the CCD output signal transmission line 21b.
The other ends of the wires 21 a and 21 b are connected to a connector receiver 22 provided on the side of the light source connector 12.
Leads to. The connector receiver 22 has a signal cable (also referred to as an EL cable).
A connector 24 attached to one end of the connector 23 is detachably connected to the connector 24, and is connected to the other end.
Connect the attached connector 25 to the CCU4 signal connector receiver (scope connector receiver).
I also write. ) 26 so that it can be detachably mounted. When the two connectors 24 and 25 are connected respectively, as shown in FIG.
The CCD drive signal from the CCD driver 31 constituting the patient circuit 30 in U4 is C
The signal charges stored in the CCD 19 are read out by being supplied to the CD 19.
You. The read CCD output signal is amplified by the preamplifier 32 in the CCU 4.
After that, it is input to the pre-processing circuit 33 to separate it into a luminance signal and a color difference signal,
After pre-processing such as correction and white balance, the isolation
One pixel constituting a secondary circuit 35 via an insulating transformer 34 as a gas insulating means)
The signal is input to the clamp circuit 36. The one-pixel clamp circuit 36 includes an insulating transformer 3
4, the signal from which the DC component has been removed is input.
A DC component is generated by a circuit 36, input to an A / D converter 37 via a low-pass filter (not shown), and converted into a digital signal.
Will be delivered. The digital signal stored in the memory 38 is controlled by a system controller 39.
Under the control of the D / A converter 41, the analog signal is read out at a predetermined timing.
After that, it is output to the TV monitor 5 together with a synchronization signal (not shown). The system controller 39 (abbreviated simply as controller) is an interface
43, the keyboard 6 is connected to the keyboard 6. By operating the keyboard 6, the T
Enter comments etc. regarding the endoscope image displayed on the V monitor 5 and
Can also be displayed. The controller 39 contacts the CCD driver 31 via the insulating transformer 45.
Then, the timing signal from the controller 39 causes the CCD driver 3
1 is a drive signal for reading is output to the CCD 19. Also, this controller 3
Reference numeral 9 denotes an isolation circuit 46 using, for example, a photocoupler and a control signal line 4.
7 and an operation switch 48 provided on the operation unit 9 of the electronic scope 2.
I have. For example, the operation switch 48 is a freeze switch for instructing display of a still image, or the like.
When the freeze switch is operated, the controller 39
An indication signal is transmitted. When the controller 39 detects this signal, the controller 38
Outputs a write inhibit signal to inhibit updating of data in the memory 38.
Therefore, the signal stored in the memory 38 before the write inhibit signal is repeatedly read.
As a result, a still image is displayed on the TV monitor 5. The controller 39 generates and controls various timing pulses, that is,
The clamp operation of the one-pixel clamp circuit 36 and the A / D conversion
Lock, read / write of memory 38 and D / A conversion clock of D / A converter 41
Perform lock control. FIG. 2 or FIG. 3A shows a freeze switch 48a of the operation switch 48.
4 shows an isolation circuit 46 connected thereto. The switch connected to this switch 48
The line 47a is connected to the power supply terminal Vc1 via the resistor R1, and the other line 47b is
It is connected to GND via the anti-R2 and the LED 50a of the photocoupler 50
The anode is connected, and the cathode is connected to GND. The collector of the phototransistor 50b is connected to the power supply terminal Vc2, and the emitter of the phototransistor 50b is connected via a resistor R3.
It is connected to GND of the next circuit 35 and to the controller 39.
You. The resistance R2 is set to a larger resistance value than the resistance R1, for example.
Even when the switch 48a is OFF, the lines 47a and 47b are fixed at a constant potential.
To prevent the emission and mixing of noise. That is, conventionally, the resistor R2
Is not provided, and when OFF, the potential of the line 47b is not determined and the line 47b is floating.
Had the functions of a noise generation and reception antenna.
In this embodiment, the power supply is connected to GND via the resistor R2, and when the power supply is OFF, the power supply of this GND is connected.
Since it is held at the same position, generation and reception of noise can be prevented. When the switch 48a is turned on, the LED 50a emits light through the resistor R1.
Current is supplied, and the LED 50a is turned on. In this case, the lines 47a, 47b
Is maintained at a potential close to GND or the power supply terminal Vc1. Also, instead of FIG. 3 (a), an isolation circuit 46 'as shown in FIG.
You may. In this circuit 46 ', a line 47a connected to one end of a switch 48a is connected to a resistor 47a.
Connected to the power supply terminal Vc1 via R4 and to the base of the transistor Q1.
Have been. The other line 47b is connected to GND of the patient circuit 30. The transistor Q1 has a collector connected to the power supply terminal Vc1 and an emitter connected to the resistor Rc.
5 is connected to GND of the patient circuit 30 via an LED, and an LED is connected via a resistor R6.
50a. Other configurations are the same as those in FIG. 3 (a). Also in FIG. 3 (b), when the switch 48a is off, the line 47a
The potential is fixed to the level of the power supply terminal Vc1 by R4, and fixed to GND when turned on.
Thus, it has the same function as that of FIG. Also, as shown in FIG. 4, the drive signal transmission line 2 through which the electronic scope 2 is inserted.
1a, the CCD output signal transmission line 21b and the control signal transmission line 47 are shown in FIG.
Shielded wires (individually) with shielded wires 21a-1, 21b-1, and 47-1
Shield means is formed. Inside each shielded wire 21a-1, 21b-1, 47-1
The signal lines (both single wires and coaxial wires) are accommodated. Further, each shield-covered wire 21a-1, 21b-1, 47-1 is covered with an insulating jacket. FIG. 5
Reference numeral 51 denotes a suction tube, and connects the connector 12 to the light source device 3.
This allows connection with suction means (not shown) in the light source device 3.
. By individually shielding the transmission lines 21a, 21b, 47, respectively,
In addition, noise is prevented from being mixed between transmission lines. For example, the drive signal transmission line 21a
, A horizontal transfer drive pulse having a high frequency. This pulse
Has a high frequency and is liable to generate radiation noise. For example, the CCD output signal transmission line 2
1b, the CCD output signal is generally at a very weak level, and
Even such leakage greatly deteriorates S / N. On the other hand, the shield hand
By shielding in stages, deterioration of S / N can be prevented. Also, control signal transmission line
If 47 leaks, erroneous control may be performed, but this can also be prevented.
. Each transmission line 21 inserted through the universal cable 11 of the electronic scope 2
a, 21b, 47 show the connector receiver 22 mounted on the side of the connector 12;
Not connected to each pin. In addition, each shield coated wire 21a-1, 21b-1, 47-1
Is attached to a lug 52 fixed with a screw fixing a metal outer frame of the connector receiver 22.
The points are connected. As shown in FIG. 4, the signal connector of the light source device 3 is connected to the connector 12.
A connector portion 53 is provided for connection to the connector receiver.
The receiver 22 is connected to a light source control signal transmission line 54. The synthesis of this transmission line 54
The shield wire is connected to the lug 52 at one point. As shown in FIG. 1, the connector section 53 includes an automatic light control circuit 55 in the light source device 3.
To be connected. This automatic light control circuit 55 has a light source connector
The connector 24 connected to the connector receiver 22, the cable 23, etc.
A video signal is input. For example, the pre-processing circuit 3 shown in FIG.
3 is automatically adjusted via the signal line 60 and the light source control signal transmission line 54.
Input to the optical circuit 55, for example, set the average value of this luminance signal in one frame period
Automatic light adjustment is performed by controlling the aperture amount of the aperture 15 with an error signal compared with the level.
Like that. As shown in FIG. 4, a net formed by knitting a metal wire into a net is provided in the insertion portion 8 of the electronic scope 2.
A tube (also referred to as a blade) 56 connects the light guide 13, the transmission lines 21a and 21b, and the like.
One end of a lead wire 58 is provided at the rear end (base end) of the mesh tube 56.
It is connected. The lead wire 57 is inserted through the universal cable 11,
The other end is connected to a pin (not shown) provided on the connector 12. Further, a treatment tool such as forceps or an electric scalpel 59 can be passed through the electronic scope 2.
A channel 65 is provided, and a treatment instrument is inserted from an insertion port 66 near the operation unit 9.
You can do it. The connector receiver 22 provided on the connector 12 of the electronic scope 2 has this connector
A connector 24 having an opening which is substantially fitted to the outer frame of the
A shield gasket 61 is attached to the inner periphery of this opening,
The contact resistance with the outer frame 22 can be reduced. This shield gasket
The slot 61 is formed of a thin copper plate or the like into a leaf spring shape so that it can securely contact the outer frame.
I'm trying. The cable 23 is used for each signal system as in the case of the universal cable 11.
And shielded with a shielded wire. Attached to the other end of this cable 23
The connector 25 is also securely connected to the cylindrical frame (reference numeral 81a in FIG. 8) of the connector receiver 26.
A shield gasket 62 for contact is provided. As shown in FIG. 6, the end of the cable 23 is
The pin 74 of the connector body 73 passes through the
, 74,... Are connected to respective signal lines. Also, the transmission lines 21a, 21b,.
Each shielded wire is connected to a metal tube 72 as shown in FIG. Metal tube 7
2 and the periphery of the ferrite core 71 are molded and fixed with a resin 75 or the like.
The noise leaked from each of the transmission lines 21a, 21b,.
Is absorbed and attenuated by the ferrite core 71 to reduce the occurrence of unnecessary radiation noise.
I have. In this case, when the ferrite core 71 is stored in the metal cylinder 72,
Since the metal part including it transmits noise, separate it to the outside of the metal cylinder 72 to prevent this.
The ferrite core 71 is provided. As shown in FIG. 7, for example, a light amount control signal line 54a for transmitting a signal for light amount control in a transmission line 54 for connecting the CCU 4 and the light source device 3 and transmitting a control signal.
The pin 74 is inserted through the small ferrite core 76 inside the metal cylinder 72.
It is connected to the. By passing the ferrite core 76, the signal line 54
a is generally at a low level to prevent it from being easily affected by noise. Also, the shield line of the signal line 54a (the signal line 54a is a coaxial line,
The shielded wire of the transmission line 54 is connected to the shielded wire of the transmission line 54. The connector receiver 26 of the CCU 4 to which the connector 25 shown in FIG.
As shown in the figure, a metal connector receiving body 81 is attached to the outside of the cylindrical frame 81a on the front end side.
A heavy-duty cylindrical metal frame 82 is insulated from the connector receiving body 81 to form a double cylinder structure.
It is provided. As shown in FIG. 9, the connector receiving body 81
It is electrically connected to the connector receiving / fixing conductor 83 connected to the GND of the circuit 30. or
As shown in FIG. 9, the connector receiving body 81 is connected to the CCU 4 side.
Connection lines are also integrated for each signal system in the same way as the transmission lines 21a, 21b, ... in the cable 23.
Are shielded by shield-covered wires 84a, 84b, 84c,.
, 84a, 84b, 84c,... Are connected to lugs 85 of the conductor 83 by conducting wires, respectively.
I have. That is, each shield coating wire 84i (i = a, b, c,...)
0 GND is connected at one point to prevent unnecessary radiation noise
Because of the potential difference that occurs when connection is not made at one point, noise due to the formation of a current path
Noise is prevented. As shown in FIG. 8, the metal part of the connector body 81 is an impedance element.
Connected to a chassis 86 serving as the GND of the secondary circuit 35 via all the capacitors C1.
And are conducted in alternating current. Further, the outer metal frame 82 is connected via the capacitor C2.
Connected to the chassis 86, the metal frame 82 acts as an antenna to generate unnecessary radiation noise.
It is suppressing that it is born. That is, if the capacitor C2 is not provided,
The metal frame 82 floats from the GND of the secondary circuit 35, and the metal frame 82
The required radio waves are easily radiated and noise is apt to penetrate.
With this, it is possible to maintain the impedance of the secondary circuit 35 at a low impedance with respect to the
Waves are made to flow toward the chassis 86 to reduce the level of unnecessary ejection noise. The capacitors C1 and C2 have a withstand voltage of, for example, 4 kV or more. For example, a capacitor having a capacitance of 680 to 1000 pF is used.
Condition that does not cause insulation failure even when a high voltage is applied to the power supply and the GND of the secondary circuit 35
It is made to satisfy. Also, as shown in FIG. 8 (or FIG. 1), the connector
In the same manner as in the case of the
ing. (Omitted in FIG. 7.) This ferrite core 87
The capacitor C1 is effective for removing noise that enters through the ferrite.
Helps the action of the core 87. As shown in FIG. 1 or FIG. 10, the CCD output signal transmission line 21b is a ferrite core.
The signal is input to the preamplifier 32 through an amplifier 88 while preventing generation and mixing of noise. Since the weak CCD output signal is input to the preamplifier 32, the patient circuit 30
Unlike the other components, it is housed in the shield case 32a to minimize noise contamination.
The force is prevented. Also, as shown in FIG.
The entire transmission line 21a of the CCD drive system connected to the connector receiver of the
, A copper tape 90 is wound around and shielded.
Thus, connection to the GND of the patient circuit 30 prevents occurrence of noise and the like. I mean
Each signal line is separated at the end of the signal line connected to the connector receiver, etc.
Insufficient shielding makes it easier to radiate noise from this end to the surroundings
However, by forming the shielding means in this way, it is possible to suppress the occurrence of noise and the like.
I have. The control signal transmission line 47 is also connected to the end of the control signal transmission line 47 through the ferrite core 91.
The connector 92 is connected to the connector receptacle of the motherboard 89. This connector receiver
On the motherboard 89 near the patient, the bypass capacitor C3
It is connected to GND of the circuit 30. (For example, in FIG.
Indicates that the capacitor is connected to GND via the capacitor C3. As described above, in the electronic scope 2, for example, a horizontal transfer clock for driving a CCD is provided.
Since the lock is transmitted, these clocks also cause noise on the control signal transmission line 47.
And is easily released outside through the transmission line 47. In contrast,
By connecting to GND via the capacitor C3, there is a great effect in reducing radiation noise. The capacitor C3 is made of ceramic or tantalum.
For example, a capacitor having a capacitance of 0.1 μF can be used. Note that a substrate constituting the CCD driver 31 in the patient circuit 30 (reference numeral in FIG. 1)
31a) through a lead ferrite (not shown)
It suppresses the generation of noise in the surroundings. As shown in FIG. 1, FIG. 2, or FIG. 11, the GND of the patient circuit 30 and the secondary circuit
35 GND is connected in an AC manner by an impedance element formed by a capacitor C4.
You. The capacitor C4 is a capacitor that withstands a withstand voltage of, for example, 4 kV. This
With the capacitor C4, the patient circuit 30 and the secondary circuit 35, especially at high frequencies,
The impedance between GND and GND is low, and both GNDs are directly connected in the high frequency band.
Thus, it has a function close to that of using a common GND. Therefore, especially in the high frequency band, the patient circuit 30 or
The high-frequency signal handled from the secondary circuit 35 is easily radiated to the outside,
Depending on the capacitor C4, the GNDs of both circuits 30 and 35 are connected in an alternating manner.
Therefore, most of the current that is radiated when not connected is GND
Can be dropped. This prevents unwanted radio waves from being emitted and emitted to other circuit parts or outside.
It can be greatly reduced. In addition, high frequency noise is likely to be incident from outside via the floating cap.
Can be reduced equivalently to the impedance at the incident portion with respect to GND,
Most of the noise is reduced to GND, and the rate of mixing in the signal system can be reduced.
. If the capacitance of the capacitor C4 is large, the EMC (electromagnetic interference problem (
EMI) and electromagnetic interference (EMS).
It may increase the leakage current, depending on the actual environment in the circuit system, etc.
The capacity may be set appropriately. Further, as shown in FIG. 1, a mother including a CPU and the like which mainly constitute the controller 39 is provided.
The flat cable 94 for connecting the board 93 and the secondary circuit 35
Noise countermeasures are taken through the core 95. In this motherboard 93
Ferrite core 98 is also used for flat cable 97 connected to front panel 96.
To reduce noise. Also, the cable 101 connected to the connector receiver 100 to which the connector attached to the cable 99 of the TV monitor 5 is connected is connected.
Noise reduction is performed through the write core 102. The motherboard 93 shown in FIG. 1 has a shield case as shown in FIG.
Shielded at 105,106. That is, the crystal plane (surface) on which the components of the motherboard 93 are mounted is shielded.
The case is covered with a case 105, and the back surface is covered with a shield case 106. Shield case
, 106a (to the motherboard 93) of the disks 105, 106
,... Are fixed to the motherboard 93 with screws 107,.
In order to enhance the soldering function, each mounting piece 105 or 106 and the motherboard 93
A conductive and rubber-like elastic gasket member 109 is interposed and fixed between
I have. By interposing the gasket member 109 in this manner, the adjacent screws 107
, 107 are fixed at separate positions, the mounting piece 105a and the motherboard 93
Even if the gasket member 109 is fixed in a state where it does not adhere,
A gap can be prevented, and the shield can be reliably performed. Further, the mounting pieces 105a and 106a are formed in the openings of the shield cases 105 and 106.
Is provided in a state where there are few discontinuous parts around the periphery. Also, the mounting pieces 105a,
On the motherboard 93 opposed to 106a, a GND land 111 is formed as long as possible.
Has been established. Therefore, as shown in FIG.
Into a mounting piece 105a of the base 105, a gasket member 109, and a mother board 93.
The formed GND land 111 and motherboard 93 are in a laminated state, and a seal is formed.
The motherboard 93 is sealed in a state where the gap is small due to the case 105, 106.
Noise emission to the outside and the intrusion of noise from the outside can be minimized.
It has become. The water leaked into the CCU 4 in the CCU 4 in FIG.
A drain hole is provided in the lower part of the housing. In the conventional example, the drain hole in this case is
Although the radiation of the noise was not sufficiently suppressed, in this embodiment the fourteenth
The shape as shown in the figure retains the water draining function and suppresses noise emission.
I am trying to. In FIG. 14 (a), the metal wire is woven in a mesh shape. In this case,
Set the size of the cache smaller than the wavelength of the highest frequency handled in CCU4
Thus, noise radiated from inside the CCU 4 can be sufficiently suppressed. Also, the fourteenth
In FIG. (B), many small holes are provided. Set the size of the eyelet as with the mesh
Just do it. Further, as shown in FIG. 14 (c), the shape may be a small oval. further
Even if the corner of the rectangle is rounded as shown in FIG. 14 (d), the corner is not rounded
Noise emission can be reduced as compared with the conventional example. In addition, as shown in FIG.
From the inlet 133 to which the plug 132 is connected, the feeder of the cable 131 and the G
Feeding lines 134 and 134 connected to the ND line and a GND line 135 are drawn inside the housing.
Plugged in and connected. In this case, the GND wire 135 is wound around the ferrite core 136 several times.
After that, it is connected to the chassis 87 inside the housing, and is externally connected via the GND line 135 to C
It suppresses noise entering the CU 4. In the electronic endoscope apparatus 1 of the first embodiment as described above, the electronic scope 2 is inserted into the body cavity.
The CCU 4 is connected to the CCD 19 in the electronic scope 2 because the
Patient circuit 30 and a secondary circuit for performing signal processing for outputting a video signal to the TV monitor 5
35 is insulated to ensure safety as in the previous example. In this case, by connecting the secondary circuit 35 to the ground, the shielding function is increased.
However, the GND of the patient circuit 30 may be electrically connected to the GND of the secondary circuit 35.
In the previous example, the shielding function was not sufficient because it was not possible.
As described above, various means for reducing radiation noise are provided, so radiation
Noise can be reduced. Also, the noise from external devices should be sufficiently low.
Can be reduced. Also, since the shielding between different signal systems is performed in the device 1, the device
1. The functions of each signal processing system inside 1 can be fully exhibited and signal processing with good S / N is performed.
be able to. FIG. 16 shows a main part of an electronic endoscope apparatus 201 according to a second embodiment of the present invention. This second embodiment is basically the same as the first embodiment except that an electrosurgical device 202 is added.
This is the configuration. An electric scalpel 59 is inserted into the channel of the electronic scope 2.
Is connected to the A terminal of the electric scalpel device 202 via the conducting wire 203. In addition, electronic
The connector 12 of the loop 2 is connected to the light source device 3 and provided on the side of the connector 12.
CCU 4 via a cable 205 provided with a connector 204 connected to the terminal 58
'. This CCU 4 'has a connector attached to the other end of the cable 205.
It has a connector receiver 207 to which the 206 can be attached. The connector receiver 207 is connected to a common contact c of the switch 208, and the contact a is
It is connected to GND of the patient circuit 30. The lever of this switch 208 is a spring 2
09, it is normally urged to turn on the contact a as shown in FIG.
I have. On the other hand, when the pin 212 of the connector 211 is attached, the lever
Is pressed to turn off the contact a, and the pin 212 is connected to the contact c.
It is. The connector 211 is connected to an electrical
Connected to the terminal S of the device 202. The P terminal is connected to one end of a transformer 215 via a capacitor.
The other end of the resistor 215 is connected to the terminal A via a capacitor. Also, this transformer
One end of 215 is connected to the S terminal via a capacitor. This transformer 21
5 is connected to a high-frequency output circuit 216, and the high-frequency output circuit 216
The output high frequency is supplied to the secondary side via the transformer 215. The P terminal contacts the body surface or the like of the patient 218 through a conducting wire 217 in a wide interview.
Connected to rate 219. On the other hand, the sheath 221 of the electric scalpel 59 is inserted
The exposed electrode protrudes from the opening at the distal end of the sheath 212, and the loop 222 is inserted into the polyp 22.
3 mag. And turning on the foot switch 224
With the control of the control circuit 225 connected to the foot switch 224,
A high frequency is output from the frequency output circuit 216. The control circuit 225 detects a current flowing through the P terminal and the A terminal.
Output signals of the input terminals 226 and 227, and the electric current flowing through the P terminal and the A terminal.
When the level ratio IP / IA is equal to or greater than the set value, the plate 2 receives a high-frequency current IA flowing through the terminal A and a "constant percentage" or more of the high-frequency current IA.
9, it returns to the P terminal, and the amount of current flowing outside this path is
Because it is small, it can be regarded as a normal use state. That is, as shown in FIG.
When a high-frequency current is applied, floating with the fluid 56 as a conductive member around the electric knife is performed.
Leakage current flows through the blade 57 and S terminal to some extent due to free capacity
There is. In consideration of the magnitude of the leakage current due to the above floating capacity, about this leakage current
The value at which the current IP becomes smaller than the current IA is determined in advance, and the value of the level ratio is set.
By comparing with the level ratio detected during actual use,
It can be determined whether or not it is in a normal use state. If it is less than the set value, the buzzer
A warning can be issued by the notification device 228. Also, to detect whether the connector 214 is connected to the electric scalpel device 202 or not.
The connector 214 is provided with a pin 231. That is, the connector 214
Is connected, the pin 231 pushes the switch lever 233 against the elastic force of the spring 232.
Is pressed to turn on the contacts a and b, and the control circuit 225 detects that the contacts are turned on.
When the foot switch 224 is turned on, a high frequency is output from the high frequency output circuit 216.
Output. In this embodiment, when the treatment with the electric knife 59 is not performed, the connector 21
1 is not connected, the switch 208 turns on the contacts a and c, and thus the electronic
The blade 56 of the scope 2 is kept connected to the GND of the patient circuit 30.
The blade 56 contributes to noise reduction. On the other hand, when the treatment with the electric scalpel 59 is performed, the connector 211 is not connected.
Therefore, the switch 208 is turned off by the pin 212, and in this case,
The mode 56 can be used for detecting a leakage current when an electric knife is used.
Other configurations are the same as those of the first embodiment. In the second embodiment, when the electric knife 59 is not used, the blade 56 is
Because it is connected to the GND of the patient circuit 30, it is possible to reduce noise generation and the like.
It is valid. When the electric scalpel 59 is used, the blade 56 is turned off from GND.
The leakage current can be detected by the
I can. Other effects are the same as those of the first embodiment. In the present invention, a TV camera is mounted on a fiber scope instead of the electronic scope 2.
Applicable to other devices as well. [Effects of the Invention] As described above, according to the present invention, the signal processing system connected to the image sensor is connected to the patient.
In a device separated into a circuit and a secondary circuit, such as between a patient circuit and an electronic endoscope, etc.
There is a means to reduce unnecessary radiation noise, so noise radiated to the outside
Radiation noise entering from the outside can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 15 relate to a first embodiment of the present invention, FIG. 1 is an overall configuration diagram of the first embodiment, and FIG. 2 is a signal processing system of a camera control unit. FIG. 3 is a circuit diagram of an isolation circuit, FIG. 4 is a configuration diagram of an electronic scope, FIG. 5 is a cross-sectional view taken along line AA 'of FIG. 4, and FIG. FIG. 7 is a cross-sectional view showing a schematic structure, FIG. 7 is an explanatory view showing a part of FIG. 6 in an enlarged manner, FIG. 8 is a perspective view showing an outline of a connector receiver provided in a camera control unit, and FIG. 8 is a perspective view showing the back side of FIG. 8, FIG. 10 is an explanatory view showing a part of FIG. 1, and FIG. 11 is an explanatory view showing that both GNDs of the patient circuit and the secondary circuit are connected by a capacitor. FIG. 12 is a perspective view showing the shield case, and FIG. 13 is an enlarged view of a part of FIG. FIG. 14 is an explanatory view showing a drain opening, FIG. 15 is a perspective view showing a connection portion to a commercial power supply, and FIG. 16 is a view showing a main part of a second embodiment of the present invention. Diagram,
FIG. 17 is an explanatory diagram showing a main part of the camera control unit in a state where the connector is not connected. DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope device 2 ... Electronic scope 3 ... Light source device 4 ... CCU (camera control unit) 5 ... TV monitor 6 ... Keyboard 11 ... Universal cable 12 ... Connector 19 ... CCD 22 ... Connector receiver 23 ... Signal cable ( EL cable) 24, 25 Connector 26 Connector receiver 30 Patient circuit 35 Secondary circuit 34 Insulation transformer (isolation means, electrical insulation means) 48 Operation switches 61 and 62 Gaskets 71 and 87 Ferrite core C1, C2, C3, C4 ... capacitors (impedance elements)

Claims (1)

Claims: An electronic endoscope having a built-in imaging device that can be inserted into a body cavity or the like; a patient circuit connected to the electronic endoscope for processing an output signal from the imaging device; A secondary circuit that transmits an output signal from the image sensor processed by the patient circuit through an electrical insulating unit and processes the transmitted signal; and a conductive part that is a reference potential of the patient circuit. And a capacitor for connecting a connector receiving portion of the electronic endoscope to which a connector is connected and a chassis portion serving as a ground of the secondary circuit among conductive portions that are reference potentials of the secondary circuit. An electronic endoscope characterized by being provided.