US2014540A

US2014540A - Induction coil

Info

Publication number: US2014540A
Application number: US752567A
Authority: US
Inventors: Victor W Thomas
Original assignee: E A HARRINGTON
Current assignee: E A HARRINGTON
Priority date: 1934-11-12
Filing date: 1934-11-12
Publication date: 1935-09-17
Anticipated expiration: 1952-09-17

Description

v. w. THOMAS INDUCTION COIL Septo w, 1935.

Filed Nov. 12; 1934 llll'llf Patented Sept. 17, 1935 INDUCTION COIL Victor W. Thomas, Waukegan, Ill., assigner to E. A. Harrington, Waukegan, Ill., trustee Application November l2, 1934, Serial No. 752,567

14 Claims. (Cl. JJM- 361) UNITED STATES PATENT GFFICE This invention relates in general to induction coils for ignition apparatus for internal combustion engines and has more particular reference to an improved casing for housing and disposing the primary and secondary coils.

An important object of this invention is in the provision of a casing in which the primary and secondary coils are separately mounted, the secondary coil in a sealed container, and the pril() mary coil in a removable element which includes the magnetic core.

A further object of the invention is in the provision of a primary ignition coil which is wound on a core providing air spaces on both sides of the primary winding for cooling it.

Further objects of the invention are in the improved means for sealing the parts of the coil casing; in improved means for holding the coil parts in place, in supporting the coil structure; in

2U connecting the coils to the terminals; and in general in producing the construction herein shown and described.

In the accompanying drawing, Fig. 1 is a sectional vieW of an ignition coil embodying this 25. invention;

Fig. 2 is a top view;

Fig. 3 is a side elevation;

Fig. 4 is a sectional detail of a s-econdary coil connection; and

30, Fig, 5 is an enlarged section showing the primary coil and its container.

In ignition coils it has been the practice to mount the primary and secondary coil elements in a container and to ll the space not occupied 351 by the coils with a plastic insulating material which hardens but is subject to heat and if the coil becomes sufficiently heated the insulating material becomes plastic, expands and exudes from the container.

40 The present invention proposes to overcome this objection by mounting the secondary coil `in a chamber closed to the atmosphere, without any plastic insulating material; to separate the primary and secondary coils entirely; and to 415 wind the primary coil on a core element which is bodily removable therewith, the element tting loosely within the secondary coil and having a core which provides an air space at the inside of the primary winding sothat the pri- 50 mary Winding is cooled from the inside and outside and does not communicate its heat nor that of the magnetic core to the secondary winding at any time.

Referring now more particularly to the draw- 55 ing, a casing element I0 preferably formed of bakelite or other similar water-proof insulating material, is preferably cast or molded in the form of a hollow ring having an outer wall I I with outside liutings I 2, and an inner wall I3 having a shouldered portion I4 at a distance 5 from the bottom of the container ring thus formed.

A secondary coil winding I5 is made of a proper size to t within the casing IG and upon the inner shell i3 against the shoulder I4. In the 10 outer end of this container a short shell section i5 is placed against the end of the coil I5 and a cap I7 is applied to the ends of the inner and outer walls or shells I2 and I3 and against the outer end oi the short shell i6 holding the coil l5 I5 firmly in place intermediate the ends of the casing member IQ.

In the cap are grooves I9 and 2D for seating the ends of the walls I3 and I2 and in the grooves are gaskets 2I and 22 or a sealing compound 20 for making an air-tight joint for the secondary coil container. The cap is held firmly in place at the end of the coil member Il) in any suitable means as by a sealing ring 22 in the form of a flange of which one edge is seated in a circular depression 23 of the outer side of the casing member IB, the other edge 24 of the flange being bent over the outer edge of the cap I'I.

This construction provides a sealed chamber for holding the secondary winding I5 tightly in 30 place and the cap il has a central opening 25 slightly less in diameter than the inner diameter of the shell i3 which is also open at the other end of the member I0 for inserting the primary winding.

For the primary winding 3U there is a hollow core member 3| also preferably made of insulating waterproof material such as bakelite. The interior opening 3i of this core member 3| is preferably rectangular to receive a laminated magnetic core 33 which is secured tightly in place therein and the outer angular corners 34 of the core are rounded outwardly beyond the sides to provide projections upon which the primary windings t@ will rest, leaving a space below the windings and between the projections 34. At the ends of the core 3l are flanges 35 with openings 33 therein communicating with the spaces below the coil windings and between the projections 34. These flanges 35 also t within the inner shell I3 so that only angular or corner portions l are in engagement with the wall I 3, leaving spaces therebetween at the outside of this primary core member so that there is a passage 55 entirely around the outside of the primary winding Within the inner shell I3.

One end of the primary core member abuts the cap I1 about its opening 25 and the other end of the core member is engaged by a hollow clamping ring 40 which is held in place on the end oi the coil member IIJ by fastening screws 4 I leaving the center thereof unobstructed for the passage of air to the primary winding. In this fastening ring 40 are opposite

terminals

42 and 43 connected by wires 44 and 45 to the ends of the primary Winding 30.

At one end of the casing member l is a terminal 41 extending in a recess 39 of the clamping ring 4I), and connected by a conductor 48 with one end of the secondary coil I and the other end of the secondary coil I5 is connected by a conductor 43 with a screw contact terminal 5l) preferably having a head 5I embedded in the outer wall I2 of the coil member Il), the end of the conductor 43 extending through the screw terminal 5B and soldered or otherwise connected therein to make a substantially fluid-tight joint. Surrounding the screw terminal 50 is a boss or flange 52, preferably circular, for seating a terminal plug 53 in which a secondary terminal wire 54 is connected. This wire has van insulating cover 55 which fits tightly in an opening 5S abutting an inserted internally threaded socket 51 adapted to engage the screw terminal 5&3. To make an electrical connection a screw 5B is inserted through the bottom of the member 51 into the end of the conductor wire 54, thereby binding it tightly in place and making a satisfactory electrical connection therefor. With this construction even if the conductor 54 does not make a fluid-tight connection with the plug member 53, the terminal member 50 does make a fluidtight connection with the wall of the casing member II) so that there is no leakage of the casing member I0 due to the electrical connec tion. The

other terminals

42, 43 and 41 may be connected to their corresponding conductors in a manner similar to that of the terminal 5B, or in any other suitable manner. An electrical conductor 45 commonly connects primary and

secondary terminals

42 and 41 when the coil is in use.

In order to support this induction coil casing there is a lateral projection 60 from the outer wall II which has a plurality of spaced perforations EI to be engaged by corresponding openings of angular brackets 62. To support the coil from one end, the cap is provided with projections 63 having spaced openings 64 for engaging the corresponding openings of one or two brackets as shown in Fig. 2, the brackets being suitably perforated or slotted for attachment to any suitable support.

With this construction it will be apparent that the secondary winding is entirely enclosed within a substantially waterproof ring casing, that the primary winding is entirely separate and distinct from the secondary and is mounted on a core in a passage to receive cooling air both inside and outside of the primary winding. Thus the greatest source of heat for the secondary winding not only is spaced from it but has an air cooling passage between it and there is little danger of overheating of the secondary winding or' overheating in the chamber containing the secondary winding. The primary and its mounting are also readily removable from the coil structure by simply disengaging the fastening screws 4I, which loosens the clamping ring 4t; and the primary and its connections may be bodily removed Without in any way affecting the secondary. The primary winding or the core may therefore be easily removed or replaced when desired.

I claim:

l. An induction coil having a casing with a 5 cover having an open passage therethrough, a Winding in the casing around the passage, a core holder with ribs to fit in the passage, a winding on the ribs of the holder leaving air spaces between the winding and the core for cooling the winding.

2. An induction coil having a closed casing with an open passage therethrough, a winding in the casing around the passage; a magnetizable core and a winding for the passage, and a holder therefor; the holder having ribs upon which the winding is wound leaving air spaces extending longitudinally in the passage for cooling the winding.

3. In an induction coil, a closed casing having 2() a winding therein yand an open passage therethrough, a hollow holder, a magn-etizable core therein, a winding on the holder, means spacing the winding from the surface of the holder to leave lengthwise air passages between the winding and holder, and the holder and its winding fitting in the casing passage to leave an air space surrounding the winding in the passage.

4. In an induction coil, a casing having a winding and an open passage through it, a winding holder to iit in. the passage having winding ribs and openings at the ends between the ribs, and a winding on the holder' leaving air spaces surrounding the winding and between the winding and the holder communicating with the openings for cooling the winding.

5. In an induction coil, a casing having an open passage through it, a winding in the casing, a holder therefor having winding ribs and end supports in the passage, a winding on said ribs, and o the end supports having openings at the ends between the ribs to form air passages within the winding and openings about the edges to provide air passages around the winding in said casing paSSage.

6. In an induction coil, a ring casing having a cover extending over the inner edge of the casing,

a winding in the casing, a winding and core holder having an end to engage the cover in the ring opening, and a plate to engage the edge of the holder at the other end of the casing leaving a central opening for the passage of air through the ring passage and through said holder.

7. In an induction coil, a casing having a central passage, a cover engaging over the inner and outer edges of the casing, a winding in the casing, means for clamping the cover to the casing, an inner core and winding and a holder therefor to lit in the passage and engage the cover at one end, and a lid at the other end for engaging the holder to conne it removably in place.

8. In an induction coil, a casing having inner and outer walls with a shouldered portion at the inside of the casing on the inner Wall, a winding tting the inner wall and abutting the shouldered 65 portion, a shell section abutting the other side of the winding and on the inner wall, a cover engaging the outer end of the shell section, and means holding the cover on the casing and the winding between the ends of the casing.

9. In an induction coil, a casing having inner and outer walls, a winding in the casing, a cover having grooves to seat the inner and outer walls, sealing means in the grooves, and a gripping band with inwardly turned edges to engage the cover and the outer edge of the casing to hold them together.

10. In an induction coil, a casing having a central opening, a Winding in the casing, means forming a stop at the margin of one end of the opening, a magnetizable core, a holder therefor engaging said stop and having longitudinal outer ribs, end flanges and openings between the ribs thereof, a winding on the ribs and between the fianges, the flanges having angular corners trimmed to fit in the opening in the casing and having openings between the corners at the margins of the flanges, thereby providing air spaces above and below the winding, and means to engage the end of the holder opposite said stop for holding it in the recess.

l1. In an induction coil, a bakelite case having inner and outer tubular walls, a Winding therein, a cover for holding the cover on the case in air sealing engagement, means providing fluid-tight contact terminals connected with the Winding through the walls of the case, a magnetizable core, a holdei` therefor, a Winding on the holder, means for confining the holder within the inner tubular Wall comprising a clamping ring having Contact terminals projecting therefrom connected with the winding on the holder.

12. In an induction coil, a tubular hollow casing, a cover therefor, means binding the cover to the casing, a Winding in the casing having eX- ternal contact terminals projecting from the casing, a second exposed winding removably mounted in the hollow of the casing, means comprising a perforated projection from the outside of the casing, perforated projections on the cover and perforated brackets to fit said projections for supporting the casing.

13. In an induction coil, a bakelite insulating 5 case, a winding therein having threaded metal terminals cast in and projecting from the case, the ends of the winding Abeing electrically connected to the terminals, a plug connection for said terminal including a threaded socket to iit the terminal, a plug member for the socket, a covered electrical conductor inserted in the plug member and a connecting screw inserted into the conductor, from the inside of the socket and making electrical contact with the said projecting terminal.

14. An induction coil comprising an insulating case having inner and outer tubular walls, a secondary winding mounted on the inside of the inner wall, means holding the Winding in intermediate position thereon including a cover, a primary winding and a magnetizable core, a holder of insulating material therefor having an interior bore for the core, the holder being mounted within the inner tubular wall and the cover forming a stop therefor at one end, a clamping ring for engaging the holder at the other end of the case, the ring having terminals projecting therefrom and connected to the ends of the primary winding and movable with the primary Winding holder when it is applied to and removed from the case.

VICTOR W. THOMAS.