Circuit Continuity Tester With Wire Insulation Piercing Means

Abstract

A circuit continuity tester for automotive circuits and the like features a simplified wire stabilizing and piercing means which prevents the wire from shifting as the pointed piercing element enters the same. The point of the piercing element is protected. A long bearing contact surface is provided between the piercing rod and the wire stabilizer. The structure is simplified, durable and economical.

Description

Various circuit testers are known in the prior art and some examples of the prior art are shown in U.S. Pat. Nos. 1,986,414; 2,445,667 and 2,509,653. While these and other prior art structures for similar purposes are capable of performing the desired function of testing the continuity of a circuit, or the like, nevertheless the known devices have certain defects and insufficiencies which detract from their practicality. In general, the known testing devices have tended to be complex and somewhat lacking in durability and they are too expensive to manufacture.

More particularly, in the prior art circuit testers which embody a wire piercing pin or element, adequate means to hold and stabilize the wire as it is being pierced has not been provided, together with means to protect the piercing point from blunting. These and other difficulties have been recognized in the art, and it is the object of this invention to provide a tester of the mentioned character which is completely practical and easy to operate, very economical to manufacture, and very rugged and durable and of simplified construction.

BRIEF DESCRIPTION OF DRAWING FIGURES

FIG. 1 is a perspective view of a circuit continuity tester embodying the invention and showing the use thereof.

FIG. 2 is a central vertical section through the wire stabilizing element, guide bearing and associated parts, the piercing point being in the inactive position.

FIG. 3 is a similar view showing the piercing point actively piercing a wire while the latter is seated in the stabilizing element.

FIG. 4 is an end elevational view taken on line 4--4 of FIG. 2.

FIG. 5 is a transverse section taken on line 5--5 of FIG. 3.

DETAILED DESCRIPTION

Referring to the drawings in detail, the numeral 10 designates a sturdy body portion and handle which also serves as a protector for an indicator light bulb 11 mounted therein. The body portion 10 may be conveniently formed from a short section of channel bar, as shown, and the main web 12 of the body portion lies behind and protects the light bulb 11 while the two side webs 13 project forwardly of the bulb and protect it from contact with a table, floor or the like, as where the tester might accidentally be dropped. Also, the open side of the body portion 10 allows the indicator light bulb to be fully exposed to view.

A substantially rigid cylindrical pin or rod 14 projects forwardly of the body portion 10 and is suitably rigidly secured to the same and has a sharply pointed terminal end 15 adapted to penetrate through an insulated wire 16 having a conductor 17 forming a part of a circuit whose continuity is to be tested.

The tester further comprises a coacting wire stabilizing head or element 18 which embodies a flat plate 19 close to one side of the rod 14 and parallel thereto and having a relatively long bearing sleeve 20 affixed to its inner side by welding or the like as indicated at 21. The welding bead extending between the elements 19 and 20 renders these elements substantially integral and rigid and very durable. The bearing sleeve 20 slidably receives the rod 14 therethrough and provides a large and stable bearing surface between the rod and the stabilizing head 18.

The head 18 has a forward terminal wire stabilizing portion formed by two converging plate sections 22 and 23 preferably arranged at right angles so as to form a trough or seat of considerable length for a section of the wire 16 being tested. The corner or apex of this trough or seat is immediately opposed to the pointed terminal 15 of the rod and a clearance opening 24 for the pointed terminal is formed through the seat or trough at the center of the same with the trough extending on opposite sides of said opening. The head 18 is freely slidable on the rod 14 and the plate 19 is sufficiently large to be grasped in one hand and drawn toward the body portion 10 to effect the desired piercing of the wire by the terminal 15, as depicted in FIG. 3. When the piercing operation takes place, the wire cannot shift laterally or escape the piercing point because of the tapered configuration of the stabilizing seat or trough which is engaging the wire 16;when the pointed terminal 15 engages the wire, the latter is wedged tightly against the seat and the point penetrates through the wire making electrical contact with the insulated conductor 17 and the point 15 emerges behind the trough or seat, as shown in FIG. 3, tightly impaling the wire. The clearance opening 24 avoids dulling or damaging the pointed terminal, as the latter at no time contacts anything but the relatively soft wire. Withdrawal of the point from the wire by a reverse shifting of the head 18 on the rod 14 is a very easy matter.

The previously mentioned indicator light bulb 11 is suitably supported within the channel body portion 10 with its filament electrically connected to the rod 14 and also electrically connected to a grounding cable or wire 25 having a resilient clip 26 on its free end for attachment to any suitable ground. Suitable insulating grommets 27 are provided between the body portion 10, rod 14 and grounding wire 25, as shown in FIG. 1.

The use of the tester, in view of the foregoing description, requires no further explanation. However, very briefly, with the clip 26 properly grounded, the wire 16 is engaged within the trough or seat of the stabilizing head 18, and the head is drawn toward the body portion 10 to cause penetration of the wire by the pointed terminal 15. If the particular circuit embodying the conductor 14 is a complete circuit, the indicator bulb 11 will glow and so indicate. If a wire is broken or the circuit is incomplete for some other reason, the fault will be detected by the failure of the light bulb to glow.

The invention is characterized by its extreme simplicity and economy, foolproof operation, and the parts are rugged and durable.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims.

Claims

I claim:

1. A circuit continuity tester comprising a body portion comprised of a flat plate having a pair of flanges extending from said plate at the ends thereof, said plate forming a main web and said flanges forming two side webs and cooperating to provide a substantially rigid channel member, a conductive rod projecting from one of the flanges of the channel member outwardly therefrom and having a pointed terminal, a sleeve of substantial length slidable upon the rod, a stabilizing head rigidly secured to the sleeve comprised of a flat plate extending parallel to said sleeve along the length of the sleeve and near one side of said rod and having a forward tapering wire stabilizing seat comprised of two plate sections arranged substantially at right angles defining an apical portion forwardly of and in advance of said sleeve, and said pointed terminal adapted to position a wire being tested said seat having a clearance opening for the pointed terminal formed therethrough at the apical portion, and a light indicator means including an indicator light bulb electrically connected to said conductive rod and anchored between flanges of the channel member and protected and covered by the main web thereof and a grounding cable anchored to the flange opposite said one flange and being in circuit with said bulb.