JPH10104268A - Test bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a safe and precise measurement by inserting a lead wire into the through-hole of a contact bar through the through-hole of an insulating cylinder, and energizing the contact bar by spring force to nip the lead wire. SOLUTION: A coil spring 3 is wound on the circumference of a contact bar 2 provided in the hollow part of an insulating cylinder 1 in such a manner as to be capable of protruding and recessing to energize the contact bar 2 in the direction of protruding from the end of the insulating cylinder 1. A collar 5 is provided in the middle of the contact bar 2, and a block 6 is provided on the end of the insulating cylinder 1, so that the contact bar 6 can not be protruded further when the collar 5 contacts the block 6. A through-hole 7 is provided in the middle of the insulating cylinder 1, and a through-hole 8 is also provided in the contact bar 2 orthogonally to the axial direction, so that the insertion of a lead wire from a matter to be measured is permitted through the through-hole 7 of the insulating cylinder 1 in a position where the contact bar 2 is retreated by a prescribed quantity, and the lead wire is nipped by the spring force of the coil spring 3 by the protruding of the contact bar 2. Thus, the connection between the contact bar 2 and the lead wire can be kept in semi-fixed state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test rod used for making a measurement by conducting a measuring device to a circuit to be measured.

[0002]

2. Description of the Related Art Conventionally, in the field of electric circuits, for example, a measuring instrument capable of measuring a voltage, a current, a resistance and the like, that is, a so-called tester has been known. In such a tester, the contact rod is brought into contact with the circuit to perform the measurement, but it is desirable that the measurement does not affect the circuit operation. It is also possible to measure high-voltage circuits that could be dangerous to the human body, or to measure circuits that could destroy circuit elements if static electricity charged to the human body flows through the circuit. is there.

[0003] For this reason, the contact rod must be able to reliably insulate from the body of the measurer when held by the measurer. Therefore, for example, a test rod is used in which a contact rod is inserted into a hollow insulating rod and fixed in a state where the tip end protrudes, and a lead wire for connecting to a measuring instrument, for example, a tester, is drawn from the rear end of the contact rod. Like that. Then, the measurer holds the test rods one by one with both hands and presses the tip of the contact rod against the circuit to perform the measurement.

However, in such a device, when performing the measurement work, both hands of the measurer are blocked. For example, when a dial, a switch, or the like must be operated during the measurement work, the measurer is required to use a test rod. The user has to change the operation, and there is a problem that the operation is extremely difficult. Further, when the test rod is semi-fixedly connected to the circuit, it is necessary to separately prepare an alligator clip or the like, or to solder a lead wire to a conductor of the circuit. When the connection is made by using an alligator clip or the like, the workbench is likely to be confused, and there is a risk that an unexpected short circuit accident or the like may occur.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and can secure the measurer without affecting the circuit operation. It is an object of the present invention to provide a test rod which can be fixedly connected.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a hollow insulating cylinder, a contact rod made of a conductor provided in the hollow portion of the insulating cylinder so as to be able to advance and retreat, and a contact rod wound around the outer periphery of the contact rod. A coil spring for urging the contact rod in the advance direction, a stopper provided on the contact rod to regulate advance at a constant advance position, and a through-hole formed in the middle of the insulating cylinder,
At a position where the contact rod is drilled in the radial direction and the contact rod is retracted by a predetermined amount, insertion of a lead wire from the object to be measured is allowed through the through hole of the insulating cylinder, and advancement of the contact rod causes the coil spring to move. It has a through hole for holding a lead wire by a spring force, and a lead wire connected to the rear end of the contact rod and sending a measurement signal to a measuring instrument.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the side sectional view shown in FIG. In the figure, reference numeral 1 denotes a hollow insulating cylinder. A contact rod 2 made of a conductor is provided in the hollow portion of the insulating cylinder 1 so as to be able to advance and retreat. A coil spring 3 is wound around the outer periphery of the contact rod 2 so as to urge the contact rod 2 in a direction protruding from the tip of the insulating cylinder 1.

The contact rod 2 is provided with a stopper 4 so that the contact rod 2 cannot be further advanced from a predetermined advanced position. This stopper 4
For example, a flange 5 fitted in the middle of the contact rod 2 and a block 6 provided at the distal end of the insulating cylinder 1 so as to contact the flange 5. Therefore, when the flange 5 abuts on the block 6, the contact rod 2 urged in the projecting direction by the coil spring 3 cannot advance any further.

A through hole 7 is formed in the middle of the insulating tube 1. A through-hole 8 is also formed in the contact rod 2 perpendicularly to the axial direction. At a position where the contact rod 2 is retracted by a predetermined amount, a lead from the object to be measured is passed through the through-hole 7 of the insulating cylinder 1. The insertion of the wire 9 is allowed, and the lead wire 9 is clamped by the spring force of the coil spring 3 when the contact rod 2 advances.

[0010] A lead wire 10 is connected to the rear end of the contact rod 2 to send a measurement signal to a measuring instrument. When the contact rod 2 rotates with respect to the insulating cylinder 1, the position of the through hole 7 of the insulating cylinder 1 and the position of the through hole 8 of the contact rod 2 do not match, and it becomes impossible to insert a lead wire. Therefore, the contact rod 2 may be provided with a detent so that it can move forward and backward while maintaining a constant relative position with respect to the insulating cylinder 1.

This detent is formed, for example, by axially symmetrically facing the inner wall of the insulating cylinder 1 and engraving two grooves in the axial direction. In this case, a pin may be fitted perpendicularly to the axial direction, and both ends of the pin may be fitted into the groove so as to be able to advance and retreat. In this way, since both ends of the pin are held in the groove, only the advancing / retreating operation can be allowed while keeping the contact rod 2 at a fixed relative position with respect to the insulating cylinder 1.

[0012]

The present invention is embodied in the form described above and has the following effects.

The contact rod 2 is retracted, and a lead wire is inserted into the through hole 8 through the through hole 7 at a position where the through hole 7 of the insulating cylinder 1 and the through hole 8 of the contact rod 2 can be seen. If the contact rod 2 is urged by a spring force, the lead wire 9
Can be held, and the connection between the contact rod 2 and the lead wire 9 can be maintained semi-fixed. Therefore, the measurer can use both hands freely and can easily operate the measuring instrument.

Further, since the lead wire 9 is directly connected to the contact rod 2, it is not necessary to prepare special tools, so that the work bench table is not confused and safe and accurate measurement can be performed. Can be. Furthermore, the test rod of the above embodiment can be measured by holding it with both hands by a measurer in the same manner as a normal test rod, and in such a case, there is an advantage that no special tool is required.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a test rod according to one embodiment of the present invention.

FIG. 2 is a perspective view showing a use state of the test rod of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation cylinder 2 Contact rod 3 Coil spring 4 Stopper 5 Flange 6 Block 7 Through hole 8 Through hole 9, 10 Lead wire

Claims (4)

[Claims] 1. A hollow insulating cylinder, a contact rod made of a conductor provided to be able to advance and retreat in a hollow portion of the insulating cylinder, and a coil spring wound around the outer periphery of the contact rod to urge the contact rod in an advance direction. A stopper provided on the contact rod for restricting advancement at a fixed advance position; a through-hole formed in the middle of the insulating cylinder; and a contact hole which is bored in the contact rod in a radial direction and retracts by a predetermined amount. At a position where the lead wire is inserted from the object to be measured through the through hole of the insulating cylinder, and the contact rod advances so that the lead wire is clamped by the spring force of the coil spring; A lead connected to the end for transmitting a measurement signal to the measuring instrument. 2. A stopper according to claim 1, wherein the stopper comprises a pin penetrated in the middle of the contact rod, and a block provided at the front end of the insulating cylinder to allow passage of the contact rod and prevent passage of the pin. A test rod characterized by becoming. 3. The test rod according to claim 1, wherein the contact rod is provided with a detent so as to move forward and backward while maintaining a constant relative position with respect to the insulating cylinder. 4. The test as claimed in claim 3, wherein the detents are formed by axially symmetrically engraving grooves on the inner wall of the insulating cylinder for fitting both ends of the pins so as to be able to advance and retreat. rod.