US1738287A

US1738287A - Electric testing tool

Info

Publication number: US1738287A
Application number: US210320A
Authority: US
Inventors: Clarence A Dirksen
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-08-03
Filing date: 1927-08-03
Publication date: 1929-12-03
Anticipated expiration: 1946-12-03

Description

Dec. 3, 1929. DlRKSEN 1,738,287

ELECTRIC TESTING TOOL Filed Aug. 3, 1927 Patented Dec. 3, 1929 CLARENCE A. DIRKSEN, OF DUBUQUE, IOWA ELECTRIC TESTING TOOL Application filed August 3, 1927.

The present invention relates to a tool for testing electric circuits, and aims to provide a novel and improved device of this character for use by electricians, such as linemen and others, the said testing device or tool having prongs thereon for piercing the 1nsulation of conductors in order to establish contact therewith for conveniently and efficiently locating breaks in the conductors.

Another object of the invention is the provision of an electric testing tool arranged in the form of a pair of pliers having a removable bloclr of insulating material on one jaw thereof for detachably supporting a plurality of prongs or contact points, which may be in the form of phonograph needles.

It is also an object of the invention to provide a device of the above indicated character, which is simple and substantial in construction, which can be manufactured economically, and which will be thoroughly efficient and practical in use.

l Vith the foregoing and other objects in view, which will be apparent as the description proceeds, the invention resides in the construction and arrangement of parts, as hereinafter described and claimed, it being understood that changes can be made within the scope of what is claimed, without departin from the spirit of the invent-ion.

'lhe invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a side elevation of my improved device, 1

Figure 2 is a longitudinal section taken on line 22 of Figure 1,

Figure 3 is a fragmentary longitudinal section talren'on line 3-3 of Figure 2, and

Figure 4 is a cross section taken on line l l of Figure 3.

Referring to the drawings, the numeral 10 design ates the device arranged in the form of a pair of pliers, having a pair of

sections

11 and 12 pivotally connected together, as at 18, so as to provide two handle sections 14 and and a pair of jaws 16 and 17. The

sections

11 and 12 are preferably constructed in the form of channel members cut away adjacent the point of pivot thereof so as to permit the member 11 to extend through the Serial No. 210,320.

member 12 for pivotal connection and operation after the manner of ordinary pliers.

in carrying out my invention, the jaw 16 has the face thereof cut away, as at 18, and a block of insulating material 19 is attached to said jaw at said cut away portion to the

side walls

20 and 21 thereof and to the connecting portion 22 at the forward end of said side members. The block 19 is positioned between the

side members

20 and 21 and has its forward end notched, as at 28, for resting on the connecting portion 22. A screw 24: is passed transversely through the rear end of the block 19 and side member 21 being threaded into the side member 20 for attaching the rear portion of the block in a rigid manner to the jaw 16 and at the forward end of the block a screw 25 is threaded therein through an opening therefor in the conneeting port-ion 22 0f the aw and is provided with an elongated head 26, the purpose of this screw 25 being to permanently attach the forward end of the block 19 to the jaw, while the screw 24 permanently attaches the rear end of the block to the jaw. The opposite sides of the block 19 are cut away, portions 27, to permit the upper faces of the block to lie flush with the side faces of the

side members

20 and 21 of the jaw 16 and by cutting away the block in this manner, shoulders 28 are provided on the block which rest on the upper edges of the

side members

20 and 21 of the jaw so as to aid in supportin the block thereon,

Extending into the block from the lower side thereof is an enlarged recess 30 which receives the upper ends of a plurality of pins 31 which have their lower ends tapered to provide sharp points, as at 32. The pins 31 are preferably arranged in two rows and are of sutlicient length to project below the block 19 when the upper ends thereof are in engagement with the bottom of the recess 30. lshonograph needles have been found very practical for the purpose for which these pins are provided, as they form an eflicient and inexpensive means for puncturing the insulation and establishing contact with the electric conductor. The phonograph needles need not be new ones, butmay be used ones which would ordinarily be thrown away. In order that the pins 31 may be firmly held in the recess of the block 19, a screw 33 is threaded through the front end of the block 19 and engages the pins so as to clamp the same together and against the opposite end wall in order .tohold said pins against accidental removal.' The screw 33 is of a size equal approximately to the width of the recess 30 so as to firmly engage the pins at the end of the recess adjacent the screw to clamp all of said pins between said screw and the opposite end of the recess. As shown in Figure 2 of the drawings the end wall of the recess opposite to that through which the screw 33 extends and designated by numeral 34, may be arranged at an angle so that when the pins are clamped in the recess the two rows are arranged in staggered relation, whereby the danger. of the wire or electric conductor being tested positioning itself between prongs or contact-points is practically eliminated.

The'elongated head 26 on the screw 25 will abut against the jaw 17 when the jaws of the tool are brought together, thus preventing the sharp points 32 on the pins 31 engaging the face of the jaw 17 which would tend to destroy the points on said pins.

In use, it can be seen that by placing an insulated'wire or wires between the jaws 16 and 17 and forcing the handles 14 and 15 together the points 32 carried by the jaw 16 will be forced through the insulation on the wire or wires as the jaw 17 engages the opside orsides thereof. The device will ound very efiicient for testing electric circuits inwhich electric lights, etc., are arranged in series therewith. In testing electric light circuits the device may be clamped in rear of the first light and if the same flashes this will indicate thatthe light and conductors to such point are in good condition. By proceeding on down the line in rear of each 7 light, it may be easily determined where the defective point is and of course in testing a circuit of this character, both wires of the circuit are clamped between the jaws of the device. 7

When the points of the pins become dull and in'efiicient, the screw 32 may be loosened 1nd new pins, such as phonograph needles or theilike, placed in the recess and the screw tightened in order, to clamp them between the screw and the opposite endof the recess. By having the block 19 constructed of insulating material, it can be seen that the user of the device will not be subjected to electric shocks. when testing wires. Having thus described my invention, what I claim as new is:

1. 1m electric circuit tester comprising a air of members pivotally connected together intermediate their ends to provide jaw portions and handle portions, a block of insulating material attached to one jaw and having a recess therein, a plurality of pins arranged in said recess and slightly protruding from the block, and a set screw threaded in the block and engaging said pins so as to clamp the same between said set screw and the opposite end of the recess.

2. An electric circuit tester comprising a pair of members pivotally connected together intermediate their ends to provide jaw portions and handle portions, :1 block of insulating material having a recess arranged therein, a screw extending through one of said jaws and into the block for attaching the block to the jaw and for limiting movement of said jaws towards each other, and a plurality of pins arranged in the recess of said block and protruding slightly from the block in the direction of the opposite jaw.

3. An electric circuit tester comprising a pair of members pivotally connected together so as to provide jaws, said jaws being of channel formation in cross section, one of said jaws having a portion of the bight portion of the channel shaped portion cut away, a

block arranged in the channel of the jaw having a portion thereof cut away, screws extending through the jaw and into the block for attaching the block to the jaw, said block having a recess arranged therein opening at the point where the jaw is cut away, a plurality of pins arranged in said recess and pro truding slightly from the jaw, and a set screw threaded in the block and engaging certain of the pins for clamping the same between said screw and the opposite end of said rccess.

4:. An electric circuit tester comprising a pair of members pivotally connected together so as to provide oppositely arranged jaws, said jaws being of channel shaped formation in cross section, one of said jaws having an opening through the bight portion thereof, a block of insulating material attached to the last mentioned jaw and having a recess registering with the aforesaid opening, screws for attaching said block to said jaw, said block having opposite side portions thereof cut away so as to provide shoulders engaging the upper edges of the channel shaped jaw, a plurality of pins arranged in the recess of said block and protruding slightly below said jaw, and a set screw threaded in said block and in engagement with certain of said pins for clamping all of said pins in the block against the opposite end of the recess.

CLARENCE A. DIRKSEN.