JPH0720612Y2 - DC voltage detection tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a DC voltage detection tester for detecting the state of circuit wiring in various DC voltage circuits, and more specifically, DC flowing through the detected circuit portion. The present invention relates to a DC voltage detection tester for determining the polarity of voltage.

[Conventional technology]

This type of DC voltage detecting tester generally has a configuration shown in FIGS. 5 and 6. That is, as shown in FIG. 5, it has an elongated cylindrical case 1 that functions as a grip portion as a whole, and the proximal end side of a probe 2 made of soft iron is screwed into this tip opening 1a. A conducting wire 3 extends from the rear end 1b of the case, and an alligator grip 4 is connected to the leading end of the conducting wire. Inside the case, the arrow-shaped light bulb 5
This electric bulb is pressed against the connection terminal 3a of the lead wire 3 introduced into the case from the case rear end 1b by the conductive coil spring 6 which is also mounted in the case in a compressed state. The tip end side of the coil spring 4 is supported by a conductive spring bearing member 7, and the spring bearing member 6 is connected to the probe 2. Furthermore, an opening 1c is formed in the cylindrical case so that the lighting state of the arrow-shaped light bulb 5 can be visually checked. FIG. 6 shows a circuit configuration formed by the above-mentioned respective parts connected in this manner.

In the tester of this configuration, the tip of the probe 2 is connected to the DC circuit portion to be detected, and the alligator clip 4 is connected to the circuit ground side chassis or the like.

When a DC voltage appears in the circuit portion to be detected, a DC current flows through the arrow-shaped light bulb 5 as shown in FIG. 6, so that the arrow-shaped light bulb 5 is turned on. Therefore, by visually observing whether or not the arrow-shaped light bulb 5 is lit through the opening 1c, it is possible to know whether or not the DC voltage appears in the detected circuit portion.

[Problems to be solved by the device]

However, the tester with the above configuration has the following problems. First of all, the life of the arrow bulb used is about 6 months when detecting a normal DC voltage of about 12V or 24V, which is extremely short. In addition, since the arrow-shaped light bulb is fixed inside the case by the coil spring that is mounted in a compressed state and its electrical contact state is maintained, each part inside these cases vibrates when vibration is applied. Therefore, there is a possibility that durability may be deteriorated. Furthermore, there is a drawback that poor contact is likely to occur. Furthermore, since the case part functions as a grip part, when inspecting the circuit part in the deep part, it is difficult to visually check the lighting state of the arrow-shaped light bulb because the hand holding the tester interferes. is there.

As described above, the conventional DC voltage detection tester has low durability and reliability, and sometimes it is difficult to visually check the lighting state of the light bulb, which is the detection result. is there.

[Means for Solving the Problems]

In order to solve the above problems, in the present invention, a probe attached to the tip of a tubular case, a ground terminal member attached to the rear end of the tubular case, and the probe inside the tubular case. A first LED lamp connected in series in the forward direction between the needle and the ground terminal member; and a first LED lamp connected in series in the reverse direction between the probe and the ground member inside the tubular case. A second LED lamp having a different emission color from the first LED lamp, a rectifying means provided between the probe and the earth member inside the cylindrical case, and a DC voltage to which the rectified voltage is applied. It is characterized by having a drive-type sounding means. Here, it is desirable that the rectifying means is a diode bridge circuit.

[Action]

In such a configuration, the first LED lamp emits light when the potential of the detection target is positive, while the second LED lamp emits light when the potential of the detection target is negative. In any of the polarities, the rectifying means rectifies the detected voltage and converts it into a unipolar voltage, which is applied as a power supply voltage to the DC voltage driving type sounding means. The type-type sounding means performs a sounding operation regardless of the polarity of the detection voltage. Even when an AC voltage is applied to the probe, the sounding means operates by the power supply voltage creating function of the rectifying means. As described above, according to the present invention, when the sounding means produces a sound, it can be audibly recognized that a DC or AC voltage is applied to the probe. Moreover,
Positive DC voltage when the first LED lamp emits light, negative DC voltage when the second LED lamp emits light, and alternating voltage when none of the LED lamps emit light, respectively. It can be visually recognized that the voltage is applied.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment FIGS. 1 to 3 show a DC voltage detecting tester according to a first embodiment of the present invention.

First, FIG. 1 shows the overall configuration of the tester of this example. As shown in this figure, the tester 10 of this example is provided with a cylindrical transparent case 11 made of synthetic resin that functions as a grip portion, and a stainless steel probe 12 is coaxially provided at the tip 11a. Installed. Further, a conducting wire 13 extends to the rear end 11b of the case 11, and a crocodile grip 14 is connected to the tip thereof. On the other hand, the tip of case 11
A hollow cone-shaped synthetic resin probe cap 18 for covering the probe 12 is detachably attached to the probe 11a.

Inside the case 11, a first LED lamp 21, a second LED lamp 22 and a current limiting resistor 23 are arranged. In this example, the emission color of the first LED lamp is set to red, and the second
The LED lamp's emission color is set to green. Inside the case, a base end 12b of the probe 12 attached to the tip side thereof projects. Further, a disk-shaped buzzer 24 is incorporated inside the case on the case base end 11b side, and a negative terminal 24b of the buzzer 24 is connected to the conductor 13. Inside the case, a first LED lamp 21 arranged in the forward direction and a current limiting resistor 23 are connected in series between the base end 12b of the probe and the alligator grip 14 in this order. In addition, at both ends of the first LED lamp 21, there is a second L arrayed in the opposite direction.
The ED lamp 22 is connected in parallel. Further, a DC voltage drive type electronic buzzer 24 is connected in series between the probe 12 and the alligator grip 14. FIG. 3 shows a DC voltage detection circuit 31 composed of these elements, and corresponding parts are designated by the same reference numerals.

Next, the structure of each of the above parts will be described in more detail with reference to FIG. First, the transparent case 11 has a cylindrical shape on one side on the base end side, and a tapered shape toward the tip side. A large diameter portion 111 is formed at the base end portion, and the large diameter portion 111 is composed of a buzzer mounting portion 112 integrally formed on the case body side and a cap portion 113 bonded to this portion 112. It is configured. Further, wiring grooves 112a and 113a having a U-shaped cross section are formed on the inner peripheral surface of these portions along the inner peripheral surface in the axial direction. on the other hand,
The probe 12 attached to the tip 11a of the case 11 is supported by a frustum-conical probe support member 121 made of synthetic resin. On the end face 122 on the base end side of the probe support member 121,
A cylindrical insertion portion 123 that can be fitted into the tip opening 11a of the case is integrally formed, and the probe 12 is attached to the case 11 side by fitting this portion into the tip opening 11a of the case and adhering it. Will be done. On the other hand, the probe support member 121
Similarly, a cylindrical projection 125 is also integrally formed on the end surface 124 on the tip side of the, and the base end opening of the probe cap 18 is formed in this portion.
18a is fitted. On the inner peripheral surface of the base end opening 18a of the cap, four guide protrusions 18b are formed at equal angular intervals in the axial direction of the cap, and these guide protrusions move the cap 18 to the probe support member. The fitting operation on the side of can be performed smoothly.

The tester 10 of the present example having the above-mentioned configuration is assembled as follows. That is, as shown in FIG. 2, the LED lamps 21 and 22 and the resistor 23 are connected to the base end 12b of the probe 12, and then these are inserted into the inside through the tip opening 11a of the case. To do. After pulling out the internal wiring from the case base end side along the wiring groove 112a, fit the buzzer 24 into the buzzer mounting portion 112, and thereafter, buzzer terminals 24a, 24b.
Then, connect the wiring drawn from the case front side. After that, the cap portion 113 is adhered to the main body side portion 112 of the case.

Next, with reference to FIG. 3, a DC voltage detecting operation by the tester 10 of this example configured as above will be described. First, the operator holds the tester 10, brings the tip 12a of the probe 12 into contact with the circuit portion to be inspected, and connects the alligator grip 14 to the ground side. This operation is similar to the conventional case. When a positive DC voltage within the detectable voltage range appears in the circuit portion to be inspected, the
A circuit that goes to the ground side is formed via the LED lamp 21 and the resistor 23, and a circuit that goes from the probe 12 to the ground side via the buzzer 24 is formed. As a result, the first LED
The lamp 21 emits red light and the buzzer 24 sounds. As a result, the operator can visually and audibly recognize that a positive DC voltage appears in the circuit under test.

On the other hand, when a negative DC voltage appears in the circuit under test, the resistor 23 and the second LED are connected from the ground side.
Since a circuit is formed toward the probe 12 side via the lamp 22, only the second LED lamp 22 emits green light, and the buzzer does not ring. Therefore, even in this case, the operator can recognize the inspection result through the visual sense and the auditory sense that the emission color is different and the buzzer does not sound.

As described above, in the tester of this example, the conventional structure in which the arrow-shaped light bulb is fixed by the coil spring in the case is eliminated, and instead of this, the LED lamp is used to configure the circuit for displaying the inspection result. is doing. Therefore, according to this example, unlike the conventional, the durability is improved,
Also, the possibility of contact failure is disclosed, and a highly reliable tester is realized as a whole. Further, since the probe is made of stainless steel, it is less likely to bend and rust than the conventional one made of soft iron, which is preferable. Further, as can be seen from FIG. 2, since wiring grooves 112a and 113a are formed in the portion on the base end side of the case, it is possible to appropriately route the wiring inside the case. There is also.

Also, in the tester of this example, the display of the inspection result is
In addition to emitting light from the LED lamp, the buzzer sounds. Therefore, especially when the part to be inspected is in a deep place and the light emission state of the LED lamp cannot be directly visually inspected, the inspection result can be known from the buzzer sound, so inspection by this kind of tester is much easier. Has the advantage that In addition to this, in the present example, even when a negative DC voltage is detected, the second light emission color different from that of the second light emission color is detected.
Since the LED lamp is made to emit light, there is an advantage that it can be used even when detecting a negative DC voltage.

Second Embodiment Next, FIG. 4 shows a DC voltage inspection circuit according to a second embodiment of the present invention. The tester of this example has the same overall configuration as that of the above example, but the test circuit 40 incorporated in the case has a negative direct current in addition to the circuit of the first embodiment shown in FIG. A circuit portion is added for driving the buzzer 24 even when a voltage is detected. In the following description, the same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 4, in this example, a diode 41 arranged in the forward direction and a diode 42 arranged in the reverse direction are connected in series between the probe 12 and the alligator grip. The connection point 43 of these diodes is connected to the + side terminal 24a of the buzzer 24. Also, the probe 12
Between the alligator grip 14 and from the probe 12 side,
The diode 44 arranged in the reverse direction and the diode 45 arranged in the forward direction are connected in series, and the connection point 46 of these diodes is connected to the-side terminal 24b of the buzzer 24. The diodes 41, 42, 44 and 45 form a diode bridge circuit as a rectifying means.

The detection operation of this example configured in this way is as follows.
When a positive DC voltage is detected by the probe 12, a circuit passing through the probe 12, the first LED lamp 21, and the resistor 23 is formed, and the LED lamp 21 emits red light. With this,
A circuit passing through the probe 12, the diode 41, the buzzer 24, and the diode 45 is formed, and the buzzer 24 sounds. On the other hand, when a negative DC voltage is detected by the probe 12, a circuit is formed from the ground side through the resistor 23, the second LED lamp 22, and the probe 12, and the second circuit is formed. LED lamp emits green light. Furthermore, in this case, from the ground side,
A circuit passing through the diode 43, the buzzer 24, the diode 44, and the probe 12 is formed. Therefore, even in this case, the buzzer
24 will ring. The buzzer 24 also sounds when an AC voltage is applied.

As described above, in the tester of this example, the buzzer sounds even when a negative DC voltage is detected. Therefore, in addition to the effect of the first embodiment described above, when a negative DC voltage is detected, The effect that the test result can be known by sight and hearing is obtained.

[Effect of device]

As described above, according to the present invention, the rectifying means is provided outside the first and second LED lamps connected in parallel with the energizing directions being opposite to each other, and the rectified voltage is applied to the DC voltage driving type sounding means. The feature is that it is done. Therefore, the following unique effects are produced. That is, regardless of the polarity of the potential to be detected, the detection voltage is rectified by the rectifying means and converted into a unipolar voltage, which is applied as the power supply voltage to the DC voltage driving type sounding means. Therefore, the direct-current voltage drive type sounding means performs sounding operation regardless of the polarity of the detection voltage. Even when an alternating voltage is applied to the probe, the sounding means operates by the power supply voltage generating function of the rectifying means. Therefore, when the sound means emits a sound, it can be audibly recognized that a DC or AC voltage is applied to the probe. In addition, a positive DC voltage is emitted when the first LED lamp emits light, a negative DC voltage is emitted when the second LED lamp emits light, and an AC voltage is emitted when neither LED lamp emits light. It is possible to visually recognize that each is applied to the probe.

[Brief description of drawings]

1 is an overall perspective view showing a tester according to a first embodiment of the present invention, FIG. 2 is an exploded perspective view showing parts of the tester of FIG. 1 in an exploded manner, and FIG. 3 is a tester of FIG. FIG. 4 is a circuit diagram showing a detection circuit portion in FIG. 4, FIG. 4 is a circuit diagram showing a detection circuit portion of a tester according to a second embodiment of the present invention, FIG. 5 is an overall perspective view showing a conventional tester, and FIG. It is a circuit diagram which shows the detection circuit part of the tester of FIG. [Explanation of symbols] 10 …… Tester 11 …… Case 12 …… Tip 13 …… Conductor wire 14 …… Alligator grip 18 …… Cap 21 …… First LED lamp 22 …… Second LED lamp 24 ...... Buzzer (pronunciation means) 112a, 113a …… Wiring grooves 41, 42, 44, 45 …… Diode of diode bridge circuit.

Claims (2)

[Scope of utility model registration request] 1. A probe attached to the tip of a tubular case, a ground terminal member attached to the rear end of the tubular case, and between the probe and the ground terminal member inside the tubular case. The first LED lamp connected in series in the forward direction and the first LED lamp connected in series in the reverse direction between the probe and the ground member inside the tubular case have different emission colors. A different second LED lamp, a rectifying means provided between the probe and the earth member inside the cylindrical case, and a direct current voltage driving type sounding means to which the rectified voltage is applied. Characteristic DC voltage detection tester. 2. The tester for detecting a DC voltage according to claim 1, wherein the rectifying means is a diode bridge circuit.