US2400647A - Attachment insert - Google Patents

Description

y 1945- w. M. KOHRING ATTACHMENT INSERT Filed June 23, 1943 INVENTOR. 1%

Patented May 21, 1946 ATTACHMENT INSERT Wilbur M. Kohring, Lakewood, Ohio, assignor to Continental Carbon, Inc., a corporation of Ohio Application J line 23, 1943, Serial No. 491,891

3 Claims.

My invention relates in general to an attachment insert and more particularly to an attachment insert adapted for anchoring a cable or making electrical contact with an electrical device such for example as an electrical resister.

An object of my invention is a. provision of an abutment contact insert which may be pressed into a recess and which cannot be readily removed or pulled out when once depressed in the recess.

Another object of my invention is the provision of an attachment insert having attachment means upon which a cable may be screwed or otherwise fastened, the attachment means bein connected to a cylindrical portion for stabilizing or rigidly supporting the attachment means against side play or misalignment within the recess.

Another object of my invention is the provision of an attachment insert which has outwardly extending teeth that dig into the side wall of a recess, as the insert is pressed into the recess, the said teeth having burr-like shaped points which oppose any force tending to remove the insert from the recess.

Another object of my invention is the provision of an attachment insert arranged to be depressed in a stepped recess having a shoulder therein, the

attachment insert having a body which fits closely within the small bore of the stepped recess to give stability to the insert within the stepped recess, the body having outwardly extending teeth to dig into the side wall of the large bore of the recess as the insert is pressed into the recess, the pressing movement of the insert into the stepped recess being arrested upon the teeth engaging the said shoulder.

Other objects and a fuller understanding of my invention may be had by referring to the following description and claims taken in conjunction with the accompanying drawing in which:

Figure 1 illustrates a cross-sectional view of an electrical resister unit having attachment inserts for connecting cables thereto;

Figure 2 is a perspective view of the attachment insert embodying the features of my inventlon:

Figure 3 is a perspective view of a resister element;

Figure 4 is a fragmentary view of my attachment insert and shows particularly the outwardly extending teeth;

Figure 5 is across-sectional view taken'along the line 55 of Figure 4: and

Figure 6 is a view of a modified electrical device or resister unit embodying my attachment insert.

With reference to Figure 1, I illustrate two of my attachment inserts, which are indicated by reference character I2, as being embodied in a resister unit such for example as a cable type suppressor which comprises generally a hollow insulated tube I0 having a resister element ii disposed within the hollow tube l0. Each end f the resister element II is arranged to be electrically connected to the electrical cables IS. The electrical connections between each end or the resister element ii and the electrical cables it are accomplished through my improved insert attachments [2 which constitute the subject matter of the present invention.

As shown in Figure 2, the attachment insert comprises a body 20 having a screw attachment means 15 extending therefrom and being inte grally connected thereto. The screw attachment means l5 may be of any suitable configuration or form and is preferably of the conventional wood screw type which screws into the central ortion of the cable I6. As illustrated, the cable generally consists of flexible strands of soft copper wire covered with an insulation which comprises generally soft rubber-like material. In attaching the cable to the screw attachment l5, it is only necessary to insert the end of the cable upon the point of the screw and screw the cable onto the screw while at the same time pressing the cable into the bore it within the hollow insulated tube ill. The rubber-like material of the cable as it is expanded by the screw I5 makes a good water-proof, tight joint between the cable and the hollow insulating tube ill. The manner in which the cable is attached to the screw i5 of my type of insert may be substantially the same as that shown in United States Patent No. 1,909,248, patented May 16, 1933, in the name of Glen F. Benkelman and assigned to the present assignee.

A great deal of difliculty has been experienced in attaching or connecting the cables to the ends of a resister element in a hollow tube, and I have been able to solve this diiflculty by the use of my attachment. The anchoring means for holding the attachment insert within the hollow tube is accompanied by outwardly extending teeth 22. The attachment insert is arranged to be pressed into a stepped recess having a first bore ll into which the body 20 closely fits and a second bore l8 into which the teeth engage. The body 0 which fits closely within the first bore i'l stabilizes the attachment insert within the stepped recess.

The screw attachment l must the so rigidly mounted that it can withstand a considerable amount 01' sidepressure and under test must be able to stand the heavy side pressure from a screw driver which is used as a lever against the side wall of the bore. l8 with the point of the screw driver engaging the screw attachment IS, The teeth 22 havea slightly larger diameter than the inside diameter of the second bore l8 so that when the insert is pressed within the stepped recess, the teeth dig into the side wall of the second bore, the pressing movement of the insert into the recess being arrested when the teeth engage the shoulder 19 between the first and second bores I! and i8.

As shown in Figure 5, the ends of the teeth have burr-like sharp points which dig into the side wall of the second bore l8 and oppose any force tending to remove the insert from the re-.

cess. such, for example, as tension being applied to the cable It. In other words, as the attachment insert is pressed into the stepped recess, the teeth scratch or plow longitudinal grooves of slight depth in the side wall of the second bore, and then when a reverse movement or pull is applied to the cables which would tend to remove the inserts, the sharp burr-like points dig fur-.- ther into the side wall and resist the removal of the insert from the stepped recess. The combined action of the teeth 22 together with the body 20 anchors and stabilizes the attachment insert l2 within the stepped recess so that the attachment insert cannot be misaigned therein and cannot be readily removed therefrom.

The body 20 of the attachment insert is pro-, vided with a depressed portion 2| on the lefthand end of the unit as shown in Figure l. The depressed portion 2| is arranged to partly pocket a mass of tin foil l3 for making a connection or contact between the attachment insert and the left-hand end of the resister element II. The depressed portion 2| of the insert, located at the right-hand end of the resister II, is arranged to receive the end of a spring M which presses against the end of the resistor element H. The combination of the mass of tin foil l3 and the spring 14 provides a good electrical connection between the resistor element H and the attachment inserts I2.

In Figure 6 I show a modified form of a suppressor, being generally referred to in the trade as a spark plug suppressor. In this arrangement, the right end of the resistor element ll engages the spring 14 which presses against a portion 26 of a hollow terminal 21 which is arranged to be connected to the distributor or other electrical part of the electrica1 ignition system. In Figure 6 only one of my attachment inserts is used and is pressed into a stepped recess of the hollow insulated tube 28 in the same manner as that described with reference to Figure 1.

In addition to being used for a cable attachment, my insert may be used for making any abutment contact whether for establishing electrical contact with a current carrying element or formaking a good mechanical engagement with an adjacent part.

Although I have described myinvention with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted scope of the invention as hereinafter claimed.

I claim as my invention: I a

1. An attachment insert adapted to be pressed into a stepped recess having a first bore portion defined by internal walls and a second bore portion defined by internal walls with a shoulder therebetween, said first bore portion being smaller in diameter than the second bore portion, said insert comprising a body and cable attachment means connected to the body and extending therefrom, said body having a stabilizing plug insert portion and an anchoring portion, said stabilizing plug insert portion being adapted to closely interfit into the first bore portion and stabilize the insert in the recess, by engaging the said internal walls thereof, said anchoring portion having outwardly extending teeth which dig into the said internal side wall of the second bore portion as the insert is pressed into the stepped recess, the pressing movement of the insert into the stepped recess being arrested upon the teeth engaging the said shoulder, and interlocking means 'on said teeth to engage the said side wall and oppose any force tending to remove the insert from the recess.

2. An attachment insert adapted to be pressed into a stepped recess having a first bore portion defined by internal walls and a second bore portion defined by internal walls with a shoulder therebetween, said first bore portion being smaller in diameter than the second bore portion, said insert comprising a body and cable attachment means connected to the body and extending therefrom, said body having a stabilizing plug insert portion and an anchoring portion, said stabilizing plug insert portion being adapted to closely interfit into the first bore portion and stabilize the insert in the recess, said anchoring portion having outwardly extending teeth which dig into the said internal side wall of the second bore P rtion as the insert is pressed into the stepped recess, the pressing movement of the insert into the stepped recess being arrested upon having burr-like sharp points which oppose any force tending to remove the insert from the recess.

3. An attachment insert adapted to be pressed into a stepped recess having a first bore portion defined by internal walls and a second bore portion defined by internal walls with a shoulder therebetween, said first bore portion being smaller in cross-sectional area than the second bore portion, said insert comprising a body and cable attachment means, said body having a stabilizing plug insert portion adapted to interfit snugly with the said first bore portion by engaging the said internal walls thereof and stabilize the insert in the recess, and said body having an anchoring portion including means with burrs thereon, said means and burrs thereon being adapted to di the insert from the recess.

WILBUR M. KOHRING.

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