US3508328A - Starting aids - Google Patents

Description

April 28, 1970 C'URZON 3,508,328

- STARTING AIDS Filed June 14, 1968 'V'IE I Q 1 IO FIGL INVENTOR JKarnad 6 m. B Y+Mw k w-7 ATTORNEYS United States Patent 3,508,328 STARTING AIDS Thomas Curzon, London, England, assignor to C.A.V. Limited, London, England Filed June 14, 1968, Ser. No. 737,103

Claims priority, applicaginsizGreat Britain, July 3, 1967,

1/67 Int. Cl. H01f 7/06; Hb 3/00 US. or. 29 -611 2 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a method of assembly of part of the starting aid which is described and claimed in our co-pending British application No. 43,-014/65.

The starting aid is of the kind having an electrically conductive member extending with clearance within an end portion of a tubular member, and surrounding the conductive member is a spirally Wound electric heating element which lies within or partially within the end portion of the tubular member, the heating element being electrically connected at its opposite ends respectively to the members.

The object of the invention is to provide a method of assembly of the heating element in the end portion of the tubular member.

According to the invention, one end of the heating element is first secured to a thin walled tubular rod, secondly the tubular rod is placed over the conductive member and inside the tubular member, thirdly the heating element is wound upon the rod by rotating the rod, the heating element being drawn through a slot in the end portion of the tubular member.

In the accompanying drawings:

FIGURE 1 is a sectional side elevation of the end portion of a partially completed starting aid to which the method of the invention is to be applied.

FIGURE 2 is a view showing the part of the starting aid omitted from FIGURE 1 prior to assembly and FIGURE 3 is an end view of the completed aid.

Referring firstly to FIGURE 1 this drawing shows the end portion of a starting aid which in use, is exposed within the combustion chamber of a compression ignition internal combustion engine. There is provided anouter 3,508,328 Patented Apr. 28, 1970 tubular member 10 which is formed from metal and located in spaced relationship within the tubular member is a conductive member 11. In order to support the conductive member 11 within the tubular member, mineral insulation 12 is provided. In the present example the conductive member 11 is the end portion of a resistance element.

Within the annular space defined between the end of the tubular member 10 and the mineral insulation 12 is a spirally Wound electric heating element which is formed from metal tape. The opposite ends of the heating element are electrically connected to the conductive member and the tubular member respectively. An end view of the completed starting aid is seen in FIGURE 3 in which the heating element is referenced 13.

The tape as shown in FIGURE 2, is first attached by welding to the end of a thin walled tube 14, having a bore slightly larger than the diameter of the conductive member 11. The tube is then positioned over the member 11 so that the tape lies within the tubular member and passes through a tangential slot 15 formed in the tubular member.

The tube 14 is then rotated thus drawing the tape into the annular space between the tube and the tubular member at the same time the tape being wound spirally about the tube. When sufiicient tape has been wound the outerend of the tape is welded to the tubular member 10 and the thin walled tube 14 is welded to the conductive member 11.

If desired a portion of the element may be wound on the tube before insertion into the tubular member the winding operation being completed as described.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

1. A method of assembling the heating element in the end portion of the tubular member of the starting aid of the kind specified and comprising first securing the heating element to a thin walled tubular rod, secondly placing the tubular rod over the conductive member and inside the tubular member and thirdly winding the heating element upon the rod by rotating the rod, the heating element being drawn through a slot in the end portion of the tubular member.

2. A method as claimed in claim 1 including the steps of securing the rod to the conductive member and the element to the tubular member.

References Cited UNITED STATES PATENTS 2,157,050 5/1939 Bilger et a1 296ll 2,936,358 5/1960 Heusser 296l1 WILLIAM I. BROOKS, Primary Examiner US. Cl. X.R.

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