JPS5834364A - Probe - Google Patents

Abstract

PURPOSE:To facilitate a countermeasure and treatment of noise using an oscilloscope, by providing a bypass circuit for noise removal capable of operating connection and disconnection selectively to a probe itself. CONSTITUTION:In order to observe a malfunction caused by the noise of an electric circuit or the noise of the extent that a noise component is contained, the waveform observation is carried out by bringing an electrode 1a into contact with an observing point and an electrode 2a with a reference electric potential point respectively while keeping opening a push button 13 open. On one hand, when there is the possibility of carrying out the malfunction of parts of the observing point by the noise, the condition connecting a capacitor 14 between the observing point and the refernce electric potential by using conductors 1, 2 as lead wires by pushing the button 13, is constituted. The existence of malfunction in this state is observed and when the effect of noise removal by the capacitor 14 is ascertained, a capacitor having the capacity of the same degree as the capacitor 14 is fitted between the observing point and the reference electric potential and the noise removal treatment is accomplished.

Description

[Detailed description of the invention] The present invention relates to a glove for measuring electrical signals.

A conventional probe of this type is shown in FIG. 1 is the first conductor, and internal conductor 3 such as a coaxial cable
It is provided as an extension or a separate body, and its tip forms an electrode 1a as a signal detection terminal. 2 is a second conductor, which is connected to an external conductor 4 such as a coaxial cable with a screw conductor 6, and is connected to conductor 1.
This is the signal return route. This conductor 2 is, for example, conductor 1
It is provided in a cylindrical shape with the terminals concentrically arranged, and an electrode 2a serving as a reference terminal extends from a part thereof. The conductor 3.4 transmits the detected electric signal to the counter and each of the oscilloscope detectors. 8 is the tip of conductor 2 and electrode 1
This is an insulating chip that insulates and supports a. 9 is conductor 1, 2
, is a case that integrally houses and holds the terminals 1a+2a of the conductor. This is a holder that is fixed to the jacket 11 of the 10Pj coaxial cable and forms a probe housing together with the case 9.

Introducing the electrical signal from the electronic circuit into a measuring instrument such as an oscilloscope or counter at step 8 of this configuration.
- To observe the waveform or measure the pulse frequency, the first electrode 1m is brought into contact with the measurement point, and the second cloth frame 2a is brought into contact with the reference potential point (for example, the ground point) for the measurement point. One way to use such a probe is to measure the noise resistance of various measurement points and perform noise countermeasure processing to examine noise countermeasures for electrical circuits. This will be explained in detail below.

'If an electrical circuit malfunctions due to high-frequency noise, the following steps are generally taken to resolve the problem:
(1) To find out which part of the malfunctioning circuit is causing the malfunction, connect a glove to the terminal part of the electrical +11S product, and measure the noise from the outside and when the electrical circuit is normal. ] Observe the difference in each signal waveform with an onroscope h by overlapping the probes. Incidentally, the noise application is normally performed by forcible addition using a noise simulator.

(2) In the observation around (1) above, when there is a part whose at waveform is significantly different between normal and noise injection.
If the component becomes the cause of malfunction or F'i (-), solder a high-frequency bypass capacitor of an appropriate capacity between the component terminal and ground.

(3) After processing around (2) above, touch the probe to the component terminal to which the bypass capacitor has been added, and confirm the noise removal effect of the innovation capacitor.

In this way, as a countermeasure against noise in electrical circuits, the signal waveforms of each part of the string are observed, countermeasure parts such as bypass capacitors are installed, and signal waveforms are observed to confirm the effectiveness of the countermeasures. There was an inconvenience in that it took time to consider. In particular, when installing countermeasure parts such as bypass capacitors, it takes time to adjust the mounting dimensions of the parts, lead wire length adjustment, and soldering.
There was a problem in that it took time to install appropriate noise countermeasure components, including fixing them.

The present invention has been made in view of the above circumstances.
By installing a noise removal bypass circuit that can be selectively operated on the probe itself, the oscilloscope can be used 1
．． The purpose of the present invention is to provide a probe that has constant noise resistance and is easy to process. .

FIG. 2 shows an embodiment of the present invention, in which reference numerals 1 to 11 are constructed in the same manner as the conventional one shown in 11th section 1.

In FIG. 2, 12 is an elastic conductor for a switch contact that is cantilevered to the conductor 2, and 13 is an elastic conductor for a switch contact that protrudes from the side of the case 9.
A push button attached to the free end of 2, 14 a conductor] This is a feed-through capacitor for bypass, with one electrode 17 located opposite the free end of 2, and the other 'electrode conductively bonded to the conductor l. .

The conductor 12 and the push button 13 constitute a movable contact of an electric/signal on/off switch, and when the push button 13 is pressed, the conductor 12
The electrode of the capacitor 14 that contacts the free end of the conductor 1 becomes the fixed contact J- of the signal switch SW, and the series circuit of the switch SW and the capacitor C is connected to the conductor 1 on the same side as shown in FIG. Intervention between 1. A bypass circuit that removes high frequency components between conductors 1 and 2 by turning on switch SW? I can smell it. Note that the capacitor 14 is used for high frequency noise k
In order to provide a bypass filter that allows Jl to pass through, a filter having a resistance of 1000 pF to 0.01 μF with respect to general high frequency noise is used.

This configuration σ) probe facilitates the study of noise countermeasures for the air circuit.This procedure will be explained in detail.

First, to observe erroneous 1rh operation due to noise in the electric circuit or the extent to which noise components are included, connect a glove to the terminal portion of the electric component while leaving fI13 open. .

In this case, waveform 1 will be observed using a probe that is no different from a conventional probe □ Next iC, ? IM, when the measurement point part is being observed to avoid malfunction or malfunction due to noise, press the V port 13. Operation 12: Connect the capacitor between the observation point and the reference potential using the conductor 1.2 as a lead wire. Connect 14 to form a prone state, and observe noise generation or malfunction in that state 17
, When the noise suppression effect of capacitor 14vC is confirmed, a capacitor of Kuta Nagisa with the same liter as capacitor 14 is installed between the observation point and the reference potential to complete the noise removal X. In the example, the results of observing the waveform at the observation point of the globe i'i and attaching the bypass filter for noise removal to that part can be quickly and easily checked.

Although a skin-penetrating condenser is preferable for the capacitor 14 due to its mounting structure, it may be replaced by providing a suitable mounting structure such as another ceramic capacitor.

FIG. 4 is a block diagram of main parts showing another embodiment of the present invention.

In this embodiment, a plurality of bypass filter elements having different passbands are provided, and one of these filter elements is selected and connected between the conductors 1 and 2. In FIG. 4, 15 is a slide conductor that is slidably attached to the case 9 in the axial direction, and 16 is a spring contact 1. 17 is a spring conductor whose other end is connected to the conductor 2 side, and 17 is a push hole provided on the slide conductor 15 together with the spring 18, and a contact 17 A is held at the inner tip of the push button 17.
contacts the slide conductor 15 and slides toward the conductor 1 side, and is urged toward the open side by the spring 18. 19A,
19B, l! Ic is a bypass filter 144 kW passing capacitor having a different capacity and disposed in the axial direction on the conductor 1 facing the sliding position of the contact 17A.

Therefore, press fa1117'f/: axial direction (arrows F, R
By sliding the capacitor (indicated by ) and pushing it in the direction of arrow P, you can select all of capacitors 19A, 19B, and 19C and connect them between conductors 12, making it ideal for considering noise countermeasures. This has the effect of making selection easier.

The filter circuit used in the non-embodiment is selected by a slide switch, but this requires a second switch on each side of the filter circuit.
Provide a push button switch similar to the one shown. 1 as a means of selection
~ has the same effect.

As described above, the glove according to the present invention has the function of connecting and disconnecting a noise removal bypass circuit between the observation point and the reference potential in addition to the No. 8 intake function for observing the electrical signal waveform at the observation point. 1. Used for noise countermeasure study. This has the effect of greatly increasing the efficiency of sowing.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a conventional probe, FIG. 2 is a vertical sectional view showing an example of the present invention, FIG. 5 is an equivalent circuit diagram for explaining the usage mode of FIG. 2, and FIG. The figures are a vertical cross-sectional view (a) and a cross-sectional view (b) taken along the line A-A, showing another embodiment of the present invention.
Dechiru. DESCRIPTION OF SYMBOLS 1... @1 conductor, 2... Second conductor, 3... Internal conductor, 12... Elastic conductor, 13... Push button, 14...
...K through capacitor, 15...slide conductor, 16.
...Spring conductor, 17...Push button, 18-X plug, 19A, 19B, 19C-[+ln 7 capacitor
1′

Claims (1)

[Claims] (1) tl! with a first electrode for detecting electrical signals; c1 conductor, a second conductor having a second electrode, and a casing for holding the first and second conductors; A noise-removing bypass circuit is provided between the conductor and the second conductor, in which an electrical signal switching means and a bypass filter that passes only high-frequency components contained in the electrical signal are connected in series. probe. (2. In the first claim,
X. A probe characterized in that the filter p has a plurality of filter circuits with different passbands, and the opening/closing means includes a switching means that can select one of the plurality of filter circuits and connect the filter circuits in series.