JPH08308796A - Connector guide part structure of electronic endoscopic device - Google Patents

Abstract

PURPOSE: To make it possible to well remove high-frequency noises which are included via external members and signal cables with a connector guide acting as an antenna and more particularly noises generated by the supply of clock frequency signals. CONSTITUTION: Plural capacitors 25A to 25C for removing the noises varying in high-frequency characteristics are directly connected between a projecting part 23 of a casing 14 on a main body 2 side and an extension part 24 of the connector guide 16 of the device arranged with the connector guide 16 for connecting the electronic endoscope side connector 8 to the main body 2. Capacitors having resonance points at frequencies of integer times the clock frequency 14.3MHz and capacitors for removing the high-frequency noises of an electric cautery are used for these capacitors 25A to 25C. Not only the high-frequency noises generated from the electric cautery but the higher harmonic noises generated by the supply of the clock frequency signals are well removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connector guide portion for connecting an electronic endoscope side connector to an electronic endoscope apparatus main body, and more particularly to a noise countermeasure structure.

[0002]

2. Description of the Related Art FIG. 7 shows a schematic structure of an electronic endoscope apparatus. An electronic endoscope 1 which is a scope is connected to a main body (also called a processor unit) 2 having a signal processing circuit. . In this electronic endoscope 1, a CCD (Charge Coupled Device), which is a solid-state image pickup device, is provided at the tip portion 3, and a rotary operation knob 5 and a forceps port 6 are arranged at the operation portion 4. The forceps port 6 is communicated with an internal treatment instrument insertion channel so that the treatment instrument can be introduced from the forceps port 6 to the distal end portion 3. Such an electronic endoscope 1 is connected to the main body 2 by a cable 9 having a light guide side connector 7 and a signal line side connector 8. Although not shown, an observation monitor is connected to the main body 2.

According to the apparatus having the above configuration, the light source light is transmitted through the light guide side connector 7 and the cable 9 to the electronic endoscope 1.
Sent to the inside of the body to be observed from the tip portion 3. Then, the object to be observed illuminated with light is captured by the CCD of the tip portion 3, and the video signal output from this CCD is
It is supplied to the main body 2 via the cable 9 and the signal line side connector 8. In the main body 2, the video signal is subjected to predetermined signal processing, and the video signal is sent to the monitor, so that the image inside the observed body can be viewed on the monitor.

On the other hand, various treatments can be performed by guiding the treatment instrument inserted from the forceps opening 6 into the body to be observed from the distal end portion 3, which is performed by observing the image displayed on the monitor. While being carried out. For example, the affected part can be excised with an electric knife.

[0005]

By the way, in the above electronic endoscope apparatus, for example, when the electric scalpel is used, high frequency noise generated from the electric scalpel is mixed into a video signal or the like,
There is a problem that it prevents the formation of a good image. Therefore, conventionally, a shield member is arranged in the outer circumference of the treatment instrument insertion channel or the outer circumference of the signal line in the electronic endoscope 1 or in the circuit on the body 2 side, and the noise component captured by the shield member is signaled. The structure that drops to the system earth is adopted.

However, the noise components generated from, for example, an electric knife are not completely removed only by the above arrangement of the shield member, and further improvement is required.
Therefore, the applicant has focused on the high-frequency noise component mixed from the exterior member of the electronic endoscope 1 and the connector guide, and the noise component induced when using the electric scalpel and the noise component radiated by the harmonic of the CCD drive clock. , This noise is to be removed.

That is, as shown in FIG.
Is provided with connector guides (scope guides) 10 and 11 for guiding and holding the connectors 7 and 8 to be connected. The connector guides 10 and 11 (particularly 11) are connected to the housing 2. Is an antenna that is electrically floating and receives high frequency noise. As the high-frequency noise, noise from an electric scalpel has been focused on in the past, but in the electronic endoscope device,
A clock frequency (for example, 14.3 MHz) signal is supplied from the oscillation circuit in the main body 2 to the electronic endoscope 1 side for a CCD drive pulse or the like, and noise generated by this clock frequency signal is generated in the connector guide 11 It was confirmed that high frequency noise of a frequency different from the noise generated from the electric knife was also generated by being guided to the antenna and radiated as an antenna. Therefore, it is also necessary to remove noise based on this clock frequency signal.

The present invention has been made in view of the above problems, and an object thereof is to generate high-frequency noise, especially clock frequency signals, which is mixed through the exterior member and the signal cable by the connector guide serving as an antenna. An object of the present invention is to provide a structure of a connector guide portion of an electronic endoscope device capable of excellently removing noise.

[0009]

In order to achieve the above-mentioned object, the invention according to the first aspect of the invention is an electronic endoscope in which a connector guide is arranged for connecting an electronic endoscope side connector to a main body side. In the device, a plurality of noise removing capacitors (fixed capacitors) having different high frequency characteristics are connected between the connector guide and the main body side casing. The invention according to a second aspect is characterized in that, as the noise removing capacitor, a capacitor having a high frequency characteristic that has a minimum impedance (resonance point) at a frequency that is an integral multiple of a clock frequency is provided.

[0010]

According to the constitutions of the first and second claims,
Clock frequencies used in electronic endoscopes, eg 14.
By providing a plurality of capacitors having a resonance frequency that is an integral multiple (1, 2, 3, ...) Of 3 MHz and having different resonance frequencies, high frequency (harmonic) noise generated by the clock frequency signal can be satisfactorily removed. As for the noise generated from the electric knife, a noise component of 2 MHz or less appears on the monitor at an integer multiple (1, 2, 3, ...) Of the frequency of 150 kHz, which deteriorates the image quality.
By using one high-frequency capacitor that removes frequency components equal to or lower than z, the high-frequency noise generated from the electric knife can be favorably removed.

By providing the above-mentioned capacitor for countering the electric knife and the capacitor for countering the clock frequency signal, both high frequency noise generated by using the electric knife and harmonic noise generated by supplying the clock frequency signal can be achieved. Can be satisfactorily removed.

[0012]

1 to 3 show the structure of a connector guide (scope guide) portion of an electronic endoscope apparatus according to an embodiment, which is shown on a signal line connector side. In the figure, the main body 2 in which the processor circuit is incorporated is the same as that shown in FIG.
On the front side, a metal casing 14 is covered with a resin panel 15. Then, a connector guide 16 made of metal is arranged in the opening of the panel 15, and the connector guide 1
Reference numeral 6 is connected to the housing 14 through a bake plate 17 which is an insulator, and inside the connector guide 16, a connector member 18 having a plurality of terminals is provided.

On the other hand, on the electronic endoscope side, a connector (signal line side) 8 is provided at the end of the cable 9, and this connector 8
A connector member having a plurality of terminals inside and fitted into the connector member 18 is arranged. In addition, the connector 8 has a claw member 20 on the side surface,
It is designed to be locked in the inner groove of the.

In such a structure, as shown in FIG. 2, the protruding portion 23 is integrally provided on the side surface of the housing 14 so as to sandwich the baking plate 17, while the connector guide 16 is provided at the end portion thereof. Also, the extending portion 24 is integrally formed at a position facing the protruding portion 23. In the embodiment, the distance t between the protruding portion 23 and the extending portion 24 is set to about 4 to 20 mm, preferably about 6 to 10 mm.
3 and the extension 24, a plurality of capacitors 25A, 2
5B, 25C, 25D ... 25N are directly connected by soldering or the like. At this time, the legs of the capacitor 25 are cut as short as possible. In addition, the above-mentioned protrusion 24
It is also possible to directly fix one foot of the capacitor 25 to the housing 14 without providing the.

The plurality of capacitors 25A,
25B, 25C, 25D ... 25N have different high frequency characteristics. FIG. 4 shows an example of the characteristics of a capacitor when noise caused by the clock frequency is removed. For example, as the capacitor 25A, a resonance point at 286 MHz, which is 20 times the clock frequency of 14.3 MHz with a capacity of 330 PF, is shown. Characteristic 100 with Pa
The capacitor of A is used as the capacitor 25B and the capacity of 220.
A characteristic 100B having a resonance point Pa at 357.5 MHz, which is 25 times higher than that of PF, is used, and a capacitor 100C having a resonance point Pc at 429 MHz, which is 30 times higher, is used as the capacitor 25C. When these three capacitors 25A to 25C are attached, the impedance characteristics shown in FIG.
Impedance decreases at frequencies near Hz.

In this way, the capacitors 25A ...
By properly selecting the high frequency characteristic of 25 N (resonance points Pa to Pn), as shown in FIG.
The impedance can be reduced within the range of up to 1000 MHz.

Further, in the embodiment, as a countermeasure against noise generated from the electric knife, for example, a capacitor 2 having a capacity of about 1000 pF for removing noise of a frequency up to about 2 MHz.
5D is attached. Of course, one noise removal capacitor for the clock frequency countermeasure and one noise removal capacitor for the electric knife countermeasure may be arranged.

Further, as described above, the distance t between the housing 14 to which the capacitor 25 is attached and the connector guide 16 is
The reason why it is set to about 4 to 20 mm, preferably 6 to 10 mm is as follows. That is, in the electronic endoscope, between the patient side circuit (primary side circuit) and the output side circuit (secondary side circuit),
A predetermined breakdown voltage, for example, a breakdown voltage of 4 kV is maintained, and it is preferable to maintain this breakdown voltage. In the embodiment, since the capacitor 25 is arranged along the bake plate 17, an interval of about 6 mm is required to maintain the withstand voltage of 4 kV (when the bake plate 17 is not aligned, If it is placed inside, about 4 mm is sufficient).

On the other hand, in the noise removing circuit including the capacitor 25, in order to remove high frequency noise favorably, it is preferable to reduce the impedance of the entire circuit. However, as is generally done, when the capacitor 25 is connected by a lead wire, the impedance component increases by 2πfL (f: frequency, L: inductance) due to the inductance component of the lead wire, and high frequency noise is removed. Efficiency is reduced. Therefore,
In the embodiment, the lead wire is not used, and the interval between the mounting portions is set within 20 mm, more preferably within 10 mm, so that the inductance component can be minimized and the noise removal effect can be enhanced.

According to the configuration of this embodiment, as shown in FIGS. 5 and 6, the clock frequency is 14.3 MHz.
Capacitors 25A and 25 having resonance points at integer multiples of z
By providing B, 25C, etc., high frequency noise generated by the supply of the clock frequency signal can be satisfactorily removed. Further, the capacitor 25D can favorably remove high frequency noise generated from the electric knife.

In the embodiment, since the capacitors 25A to 25N, which are cut as short as possible, are directly connected between the housing 14 and the connector guide 16, no lead wire is required. , The impedance becomes smaller when pulled. As a result, the high frequency noise removal efficiency is further improved.

In each of the above-described embodiments, the noise removal for the connector guide 16 (11 in FIG. 7) of the signal line side connector 8 has been described, but the connector guide for the light guide side connector 7 in FIG. The same may be applied to 10).

Further, in the above embodiment, the capacitor 25A
25N are separately connected, but the printed circuit board or the like on which the above-mentioned plurality of capacitors are mounted in advance is once attached to the terminal portion formed on the projecting portion 23 of the housing 14 and the extending portion 24 of the connector guide 16. It may be configured to be connected to.

[0024]

As described above, according to the invention of the first aspect, between the connector guide and the main body side casing,
Since multiple noise-removing capacitors with different high-frequency characteristics are connected, the connector guide serves as an antenna, and various high-frequency noises are mixed in via the exterior member or signal cable, for example, noise generated by using an electric knife or clock frequency signal. It is possible to satisfactorily remove the harmonic noise generated by the supply of.

According to the second aspect of the present invention, the noise removing capacitor having the high-frequency characteristic that has the minimum impedance at a frequency that is an integral multiple of the clock frequency is used. The generated high frequency noise can be efficiently removed.

[Brief description of drawings]

FIG. 1 is a top view showing a structure of a connector guide portion of an electronic endoscope apparatus according to an embodiment of the present invention.

2 is a side view of the connector guide portion of FIG. 1, showing a side view of FIG. 3;
It is a II-II sectional view.

3 is a front view showing the connector guide portion of FIG. 1. FIG.

FIG. 4 is a diagram showing high frequency characteristics of a plurality of capacitors according to an example.

5 is a diagram showing high frequency characteristics obtained with the capacitor of FIG.

FIG. 6 is a diagram showing a high frequency characteristic of a capacitor obtained in an example.

FIG. 7 is a perspective view showing an overall configuration of an electronic endoscope apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope, 2 ... Main body, 8 ... Signal line side connector, 14 ... Housing, 16 ... Connector guide, 23 ... Projection part, 24 ... Extension part, 25A-25N ... Capacitor.

Claims (2)

[Claims] 1. In an electronic endoscope apparatus in which a connector guide is arranged to connect an electronic endoscope side connector to a main body side, a high frequency characteristic is provided between the connector guide and the main body side casing. A structure of a connector guide portion of an electronic endoscope device, wherein a plurality of different noise removing capacitors are connected. 2. The electronic endoscope apparatus according to claim 1, wherein the noise removing capacitor is provided with a capacitor having a high frequency characteristic that has a minimum impedance at a frequency that is an integral multiple of a clock frequency. Connector guide structure.