US2447376A - Ignition apparatus - Google Patents

Description

Aug. 17, 1948. 1-. TOGNOLA IGNITION APPARATUS Filed May 28, 1943 v Fig. 4

A m m m ATTORNEY Patented Aug. 17, 1948 IGNITION APPARATUS Tullio Tognola, Sidney, N. Y., assignor to Bendix Aviation Corporation, New York, N. Y., a corporation of Delaware Application May 28, 1943, Serial No. 488,850

8 Claims. (Cl. 175-361) This invention relates to ignition apparatus for internal combustion engines and more particularly to a voltage transformer adapted for use in such a system.

One of the objects of the present invention is to provide a'novel ignition coil adapted for use in a low tension distribution system wherein the voltage is stepped up at a coil located adjacent the spark .plug.

Another object of the invention is to provide a novelly constructed core and coil assembly and amethod for making the same.

Still another object is to provide a novel high hereinafter.

one side or arm I l' of a, novel laminated rectangular core l2, which will be more fully described The coil windings are preferably surrounded by an insulated casing l3 and it, in turn, is encased in a'novel manner by a rigid metallic housing consisting of two similar quartar-parts l4 and I5 and a half-part or cover IS.

The two base parts l4 and i5 of the coil housing engage the opposed faces of the exposed portion of laminated core I2, thereby forming a sort of cradle for the coil. These parts of the housing are preferably secured to each other and to the tension terminal connection for an encased ignition coil.

A further object is to provide a novelly housed ignition coil and novel means for securing the same to an engine.

The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention, reference for this latter purpose being primarily had to the appended claims.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

Fig. 1 is a side elevation view, mostly in section and with parts broken away, illustrating one form of ignition coil embodying the features of the present invention, the section being taken sub-- stantially on line l| of Fig. 2;

Fig. 2 is an end view of said coil as viewed from the bottom in Fig. 1;

Fig. 3 is an enlarged scale detail view, partly in section and with parts broken away, showing a. portion of the novel high tension terminal for the coil of Fig, 1; and,

Fig. 4 is a detail view showing oneform of the core for the coil of Fig. 1.

The single embodiment of the invention illustrated in the accompanying drawings, by way of example, is in the form of a housed transformer coil unit particularly adapted for use in a low voltage distribution ignition system for an in: ternal combustion engine, that is, in a system where the current is distributed at its generated voltage and stepped up to sparking voltage at a transformer near each spark plug. As shown, the primary and secondary windings of a transformer coil III are concentrically wound and surround Cover [6 is formed with a hollow boss l9, which I is open at one end to receive the socket of a plug and socket connector for a high tension output terminal and is open at the other end to receive the socket 20 of a low tension plug and socket connection for the incoming current at primary generated voltage. Socket 20 may be of the wellknown "Cannon plug type and is secured in position by screws 2|. The conducting element 22 of said socket is connected by means of an insulated lead '23 to one end of the primary winding of coil l0 forconducting current to the coil from a suitable source of electrical energy, such as from a battery or the coil of a magneto-generator. The socket for the high tension or output terminal of the coil is adapted to receive a suitable terminal of a high voltage conductor and comprises an insulating tube 24 having a slot 25 adjacent the inner end thereof in the side adjacent to coil Ill. The lower end of tube 24 preferably rests on an insulating block 26, which is seated on a shoulder 21 in boss IQ of cover l6.

Novel means adapted for facilitating the assembly oi the housing around the coil and for minimizing the danger of flash-overs within the coil housing are provided for connecting the output end of the secondary winding 28 of coil Ill to a terminal in socket tube 24. In the form shown,

ofbracket 2a is preferably s'ufllcient to prevent any material angular' movement. of1 tube .24

. around its own longitudinal axis.

The upper end of spring has a straight centube .24, has the lower turn thereof inclose en gagement withthe outer wall of metallic tube 34 are desired, adjacent laminations coil; as shown in Fig. 4. If, on the other hand, a small gap is desired in the core or magnetic fluxpath to eifect a more rapid dissipation of the residual flux therein aftereach-"excitation,-

the cuts or gaps 4|! of all the lami'nations may' be superimposed or made to coincide at the same ,end of the coil and, hence, provide the desired to remove.v some material when making the cuts between a flange 36 formed on the tube interme- 40,- the amount to be removed dependin upon the diate the ends thereof and a washer 31 which fits over said tube'and engages an'intemal shoulder 1 insocket. against which it is yieldably held by spring 32. Washer 3'! and the turn of spring 35 around tube 34 are clamped in' place against flange 36 by spinning the lower end of said tube against the lower face of said washer. When the parts are assembled in the positions illustrated, spring 32 is preferably under slight tension so as to hold the vpartsin assembled relation.

Theadjacent ends of the primary and'second- 'ary windings of boil it) may be grounded in the usual manner by connecting the same to a portion of housingmember i5,-'such as by .meanso -aset screw 38. The free space within housing l4, l-5, I6 is preferably filled with an insulating compound 39. Polymers of cashew-nut-shell oil andllnseed oil have been found suitable for this purpose, the same being injected through suitable openings, such as at 38a, into the assembled'housing in liquid form with-the aid of vacuum and/or pressure. The compound may be injectedat one of the openings 39a while the other serves as a bleed port for the expulsion of air. The filling compound is preferably supplemented with a drying agent so that it will set to a solid form by chemical reaction without the presence of oxygen.

Setting of the filler may be facilitated by suitable of socket 24 above washer 31 may be fi led with a removable plug. Any filling material which does enter this socket may bereadily removed either before or after the compound has set.

Coil i0 and core l2. the latter of-whlch forms themagnetic flux path for the coil, are preferably the present invention. The coil is first wound on a tube of paper or like material (not shown) and the laminations' of the core are thereafter installed.' For this purpose each lamination of the between the mounting tube and lugs 41. I

' thickness of. pad 45 should be suiiicient to neheating. "During the filling process, that portion gap. In the latter instance, it may be desirable width of the gap desired. Thechoice of. these two constructions will-depend upon the particular engine on which the coils are used and whether successive excitations of .the transformer coll are ofthe same or opposite polarity.

Novel means are also provided whereby the housed coil, as heretofore described, may besatisfactorily mounted on a hollow tube surrounding a valve rod or the like on an engine. As shown,

parts-l4 and I5 of the coil housing have two pairs of lugs 4| formed integrally therewith, the adjacent faces of said lugs being arcuate for engaging oneyside of said hollow tube. Flexible metal straps 42 engage the other side of said'tube' and are anchored to housing cover l6, such as by means of-nuts 43, that engage the threaded ends of said straps and serve to tighten the same.

In order to avoid the possibility of crushing thereof are in alignment with the edges of lugs 4! to thereby definitely limit the pressure which can be applied to the supporting tube by straps 4-2. Aresilient pad 45 (Fig. 2) is preferably placed The cessitate some compression there-of before the edges of spacer elements engage the edges of lugs 4|. A satisfactory clamping. pressure is thus assured without running the risk of crushing the ly protected from damage by the elements, shock,

'- assembled in 'a novel manner comprehended by i core is preferably originally formed as a solid or continuous rectangular or other suitably shaped piece and then cut at 40 without removing any appreciable amount of metal-to permit the instal-' lation thereof on the wound coil. The resulting lamination is accordingly in the form of an elongated strip of flexible metal, the strip having turns or bends therein 50 that the ends thereof are adjacent each other In the form shown. each lamination consists of two parallel, longitudinally excompleted coil by bending or flexing the same so that the end portion or arm 46 thereof may be passed through the central opening of the coil, 1. e., through said paper tube or the like. If desired, the core laminations may be so formed that the external or exposed portion of thecore as installed will extend completely around the coil instead of around only half of the latter as shown.

If the characteristics of a-solid or closed core samelis not limited thereto.

vibration, oil, heat, or otherwise and whereby the same may be adequately and safely secured to an engine in an "advantageous and accessible I position. Novel means for electrically connecting a housed coil to a high tension terminal-within the housing are also provided whereby installation of the housing around the coil is facilitated and danger of improper or faulty installation is substantially eliminated. Additionally, there is provided a novel, simplified transformer coil and core assembly which is flexible andreliable in usea'nd which may be rapidly and inexpensively manufactured in accordance with a novel method of manufacture comprehended by the invention.

Although only a single embodiment of the invention has been illustratedand described in detail, it is to be expressly understood that the Changes may be made, for example, in various details of the design and arrangement of parts illustrated and other suitable materials may be used in lieu of the filling compounds mentioned. Other changes which do not depart from the spiritand scope of the invention will now be apparent to those skilled in the art. For a definition of the limits of the invention, reference is had primarily to the appended claims.

are installed with the cuts 40 thereof at opposite ends of the- What is claimed is:

1. In apparatus of the class described, a tubular coil of electrically conductive material, an insulating casing around said coil, laminated metallic means forming a magnetic flux path around a portion of said coil, each lamination of said means being constituted by an elongated strip having bends therein so that the ends thereof are adjacent each other, one end portion of each of said laminations extending through the central opening in said coil, a metallic housing cooperating with the exposed portion of said laminated means for enclosing said coil and casing, a socket in said housing including a tube of insulating material adjacent to and extending longitudinally of said coil, a terminal in said tube intermediate the ends thereof, and means for connecting said terminal to one end of said coil including rigid conducting means secured to said casing and extending through a slot in one side of said tube for limiting angular movement of the latter and an extensible resilient conductor for mechanically and electrically connecting said terminal and said conducting means within said tube.

2. In apparatus of the class described, an igni-- tion coil having primary and secondary windings, an insulating casing for said coil, a metallic housing enclosing said coil and casing, a socket in said housing including an elongated tube of insulating material for receiving a plug connector, terminal means in said tube intermediate the ends thereof, and means for connecting said terminal means to the high potential end of said primary winding including rigid conducting means secured to said casing and extending through an opening in one side of said tube for limiting angular movement of the latter and extensible resilient means mecha nically and electrically connecting said terminal means and said rigid conducting means within said tube.

3. In apparatus of the class described, a coil, an insulating casing for said coil, a substantially closed core extending through said coil and surrounding a portion thereof for forming a magnetic flux path, a pair of housing members cooperating with theexposed portion of said core and secured thereto, a third housing member secured to said pair of members, whereby said coil is completely enclosed, a socket in one of said housing members, said socket including an elongated tube of insulating material adjacent -to and extending longitudinally of said coil, terminal means in said tube intermediate the ends thereof, and means for electrically connecting said terminal means to one end of said coil including relatively rigid conducting means secured to said casing and extending through one side of said tube and extensible resilient conducting means mechanically and electrically connecting said terminal means to said rigid conducting means within said tube.

4. In apparatus of the class described, a coil. a metallic housing enclosing said coil, a socket in said housing including an elongated tube of insulating material, terminal means in said tube intermediate the ends thereof, and means for connecting said terminal means to one end of said coil including conducting means extending from said coil into said tube and extensible resilient means mechanically and electrically connecting said terminal means and said conducting means within said tube.

5. In apparatus of the class described, a coil,

a metallic housing enclosing said coil, a socket in said housing including an elongated tube of insulating material, terminal means in said tube intermediate the ends thereof, means for connecting said terminal 'means to one end of said coil including conducting means extending from said coil into said tube and extensible resilient mean mechanically and electrically connecting said terminal means and said conducting means within said tube, and a filler of solid insulating material filling the space within said housing and tube inside said terminal means.

6. A transformer comprising a casing, a, transformer coil within the casing, an interiorly'insulated hollow boss on the casing, means comprising a lead and a conducting element connected to the low tension winding of said coil and extending into one part of said hollow boss, a filler of insulating material within said hollow boss and surrounding said lead and said element, -a bracket electrically connected to the high tension winding of said coil projecting within the hollow boss, a metal washer supported within the hollow boss, a tensioned spring connecting the bracket and washer, a filler of insulating material within said hollow boss and surrounding said bracket and said spring, and spring contact means carried by the washer within the boss.

7. A transformer comprising a casing, a transformer coil within the casing, a hollow boss on the casing, means connecting the low tension winding of the coil with an electrical connection, means connecting the high tension winding of the coil with the interior of the boss, a contact within the boss, a tensioned spring connecting said contact and said high tension connecting means, and a filler of insulating material filling the space within the boss about said spring.

8. Means for connecting the winding of a transformer to a cable contact comprising a tubular member having a connection to the transformer winding extending therein and a cable contact spaced from said connection, means to close the tubular member at the said contact, a spring under tension connecting said contact and said connection, said tubular member containing and said spring being set in insulating material.

TULLIO TOGNOLA.

REFERENCES cI'rEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 407,618 Slattery July 23, 1889 527,070 Packard Oct. 9, 1894 995,400 Cavanagh June 13, 1911 1,209,266 Currier Dec. 19, 1916 1,486,648 Evans Mar. 11, 1924 2,113,735 Mascuch Apr. 12, 1938 2,136,609 Butterfield et a1. Nov. 15, 1938 2,334,584 Rich Nov. 16, 1943 2,382,857 Camilli Aug. 14, 1945 2,385,460 Omansky Sept. 25, 1945 FOREIGN PATENTS Number Country Date 114,072 Australia Oct. 30, 1941 474,417 Germany Apr, 2, 1929

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