US2377621A - Ignition apparatus - Google Patents

Description

June 5, 1945.

J. R. FREI IGNIT ION APPARATUS Filed May 29, 1942 Patented June 5, 1945 UNITED STATES PATENT OFFICE IGNITION APPARATUS Application May 29, 1942, Serial No. 444,993

6 Claims.

This invention relates to ignition apparatus for internal combustion engines or the like and more particularly to current genera-ting and distributing means for an ignition system.

One of the objects of the present invention is to provide a novel magneto-distributor unit which is particularly adapted for use in the ignition system of an engine with a small number of cylinders. I

Another object of the invention is to provide a novel and sturdy current generating and distributing apparatus which is so constructed as to consume a minimum of space and yet have the parts thereof arranged to permit easy and quick inspection, repair or adjustment.

Still another object of the invention is to provide a magneto-distributor unit for an ignition system wherein parts may be readily reversed to adapt the same unit to different engines.

A further object is to provide a novel device of the above character wherein the rotating element of the distributor mechanism is mounted in a novel manner on the shaft of the magneto rotor.

Another object is to provide apparatus of the above character wherein the circuit breaker means and the distributor mechanism are combined in a novel manner in the interest of compactness and simplicity.

Another object is to provide a magneto-distributor unit wherein the possibility of failure and misadiustmen-t are reduced to a minimum.

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 drawing. It is to be expressly understood, however, that the drawing is for the purpose of illustration only and is not intended as a definition of the limits of the invention, reference for this latter purpose being had primarily to the appended claims.

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

Fig. l is a side elevation, partly in section and with parts broken away, showing one form of magneto-distributor unit embodying the present invention, the section being taken substantially on line I-l of Fig. 2;

Fig. 2 is an end view of said uni-t with the cover removed to show parts of the circuit breaker mechanism and distributor;

Figs. 3 and 4 are sectional detail views showing the breaker cam and rotatable distributor element of the unit of Fig. 1,, the sections being taken substantially on line 3-3 of Fig. 4 and line 4-4 of Fig. 3, respectively; and,

Figs. 5 and 6 are sectional views of a modified breaker cam-distributor finger unit which may be used in the device of Fig. 1, the sections being taken substantially on lines 5-5 of Fig. 6 and 6-6 of Fig. 5, respectively.

The single embodiment of the invention illustrated in the accompanying drawing, by way of example, is adapted for generating high tension current and distributing the same to the sparking plugs of a two-cylinder engine. The current generating means, as shown, comprises a two-pole magnetic rotor it having a permanent magnet II and a pair of laminated pole shoes l2 mounted on and connected with a shaft IS. The latter is journaled in a pair of ball bearings l4 and I5 mounted respectively in the end wall [6 of a cast housing ll and in a transverse partition or bearing plate l8 removably mounted in the central portion of said housing. Magnetic rotor l0 cooperates in a manner well understood in the art with a pair of laminated stator poles l9, l9 to induce electrical current flow in the primary winding of an ignition coil 20. The latter is provided with a central metallic core 2|, the ends of which rest on the upper ends of stator poles ill to complete the path for magnetic flux through the coil. The second or high tension winding of coil 20 is provided with a terminal 22 by means of which it is connected to the input terminal 23 of a distributor to be hereafter described. Coil 20 extends down into housing l l and is further housed by a cover 24 which is removably secured, such as by stud bolts 25, to the top of housing body ll.

Rotor shaft I3 is provided at one end with a r splined portion 26 adapted to drivably engage the drive member of an engine. At the opposite end, within a compartment 21 in housing I! bounded by hearing plate or partition l8 and a removable end cover 28, said shaft has a circuit breaker cam 29 mounted thereon. The latter is shown as being keyed on a tapered portion of the rotor shaft and held thereon by a stud bolt 30 and washer 3|. The recessed end of cam member 29 may be closed by a threaded plug 32, if desired. Cam 29 is adapted to periodically operate a circuit breaker 33 to be more fully End cover 28 is held in described hereafter. place by a plurality of studs 28'.

The high tension current distributor which. is novelly combined with the current generating means comprises a distributor block 34 of molded insulating material and a molded rotatable element 35, both of which are mounted in a novel manner. Block 34 is piloted in plate l8 at 3B and is secured in place by means of four bolts 31, which also serve to secure said plate to hous-.

ing i7. Bolts 31 have threaded engagement with bosses 3'! formed on the inner'surface of housing ll. vertically therethrough are three spaced metallic strips or conductors 38, 38' and 3919.11 of which project into an arch-shaped recess 40 in the distributor block through which shaft l3 extends. The upper ends oi strips 38, 38' terminate in cylindrical recesses 4|, 4| in the top of block 34 and the upper end of strip 39 has resilient terminal 23 secured thereto.

Directly above recesses 4i, 4!, casing cover 24 is provided with openingsin which a pairot externally threaded ferrules 42 are secured. Extending from ferrules and the recesses 4|, 4| are tubes 43 of insulating material. The structures thus formed constitute sockets for radioshielded plug-in connectors 44, 44, which may be of any well-known construction, for connecting distributor conductors or terminals 33, 39' to the spark plugs of an engine (not shown). If desired, the insulating tubes 43 may constitute parts of the plug-in connectors, the lower ends of which may be provided with a resilient contact member 45 in accordance with well-known practices,

Rotating distributor element 35 is preferably mounted in a novel manner, the main insulating body thereof being molded on and positively carried by a roughened, irregular-shaped portion of cam member 29. Element 35 is substantially cylindrical and has a metallic insert 46 (Fig. 3) provided with three angularly spaced prongs or fingers 41, 48 and 49 that project beyond the periphery thereof into spark gap relation with the lower ends of strips 38, 38' and 39. Said fingers are so positioned as to periodically complete circuits for the conduction of high tension current to the spark plugs of a two-cylinder, V-type engine in a manner to hereinafter appear. In order to minimize the possibility of arcing or fiashovers from the distributor conductors to ground, the surface of the insulating body of member 35 may be corrugated, as at 50, and an insulating sleeve 5| may be placed around shaft 13 inside of member 35.

In the illustrated embodiment, cam 29 is provided with two lobes spaced 180 apart for periodically separating the points of circuit breaker 33. The latter may be of any suitable design, the one shown comprising a stationary contact point 52 (Fig. 2) carried by a slotted metallic bracket 53 which is secured to block 34 for vertical adjustment by means of screws 54. gages a thin metallic plate 55 which is, in turn. connected to ground through one of the bolts 31, thereby connecting point 52 to ground. The movable contact point 55 of the breaker mechanism is carried by a spring arm 51 that is secured to a metallic bracket 58 which is, in turn, secured to and insulated from ground by distributor block 34. Bracket 58 is secured to said block by screws 59 and 60 and supports a second spring arm BI on which is mounted an insulated cam follower 62. The latter is held against cam 29 by spring arm 6! and engages arm 51 to separate points 52, 56 when the follower is engaged by a lobe of the cam.

Also mounted on and supported by distributor block 34 is a condenser 63. The latter is held in Molded into block '34 and extending position'by a metallic clamp 84 secured to the distributor block in contact with ground plate 55 by means of a screw 65. Speaking in the electrical sense, one side of condenser 63 is thus connected to ground through its metallic casing, clamp 64 and plate 55. The other side of the. condenser is electrically connected to the 1nsu-, lated side of circuit breaker 33 by means of a conductor 65, the end of which is secured in place by terminal screw 60. It will thus be seen that bearing plate I8, distributor block 34, breaker mechanism 33 and condenser 63 may be assembled and installed as a unit in the magneto casing I1, 24. Also, the desired permanent ground connections are made automatically upon the installation of said unit in the casing, as is also the connection 22, 23 between the secondary winding of coil 29 and distributor block conductor 39.

It will be noted that screws 54, 54 are diametrically disposed with respect to screws 59 and 59 and that a second opening 55 is provided for screw 65 so that the mounting of the circuit breaker 33, condenser 63 and ground plate 55 may be readily reversed for the purpose of convenience on difierent engines. It will be understood that threaded metallic inserts are molded into block 34 for receiving the threaded ends 0! screws 54, 59, 60 and 65.

The primary or low tension winding of coil 29 is connected to the insulated side of circuit breaker 33 at terminal 59 by an insulated conductor 61. Although not shown in the drawing, a connection may be made from terminal 59 or 50 to an ignition switch whereby the primary of the ignition coil may be grounded in the usual manner to render the magneto inoperative for generating high tension current. I

In the operation or the magneto above-described, current is induced by the magnetic rotor, in a manner well understood in the art, in a circuit including the primary winding of coil 20 and circuit breaker 33. When points 52, 55 01 the latter are separated at predetermined intervals by cam 29 during rotation thereof, high-tension current is induced in the secondary winding of said coil and flows through terminals 22, 23 to the center conductor 39 of distributor block 34. When the rotating distributor element 35 is in the position illustrated in Fig. 3, high tension current from conductor 39 Jumps to finger 49, flows through insert 46, jumps the gap between finger 48 and conductor 39, and from there flows to one of the engine spark plugs through the plug-in connector 43, 44. The relative positions of the parts are such that the second spark or flow of high tension current to the other spark plug of a two-cylinder engine occurs when lingers 41 and r 48 of element 35 are opposite conductors 39 and 38' of the distributor block.

The rotatable distributor element 35' of Figs.

above-described magneto when the latter is used on engines on which 360 firing is required. The prongs or fingers 19 and H cooperate with conductors 38' and 39, respectively, to complete the 26,61 (,ozu.

and distributing apparatus of a simplified nature wherein the parts are so constructed and assembled as to render the same substantially foolproof insofar as proper adjustment of the parts is concerned. The novel apparatus provided also has the parts thereof combined and assembled in a novel manner to render the same compact and readily accessible for inspection and repair. The construction and assembly of the complete apparatus is also facilitated by the fact that the parts may be assembled into a small number of major units before the main assembly is undertaken. The invention is also adapted for rapid and inexpensive manufacture as well as long life in operation without appreciable expert care.

Although only a single embodiment of the invention is illustrated and described in the foregoing drawing and specification, it is to be expressly understood that the same is not limited thereto. For example, the invention may be incorporated in magnetos adapted for use on engines having more than two cylinders. Various changes may also be made in the design and arrangement of parts illustrated without departing from the spirit and scope of the invention, as 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.

What is claimed is:

1. Apparatus for generating and distributing electrical current comprising a housing, an induction coil in said housing, a magnet system including a rotor for inducing current in the primary winding of said coil, a bearing in an end wall of said housing for supporting one end of said rotor, a bearing plate having a bearing therein for supporting the other end of said rotor, a circuit breaker cam on said rotor, distributor means for distributing current from said coil to the spark plugs of an engine including a distributor block of insulating material and a rotatable element molded onto and carried by said cam, and metallic terminals molded in said block and element in spark gap relation, one of the terminals in said block being directly connected to the secondary winding of said coil, common means for securing said bearing plate and block together and to said housing. a circuit breaker having separable points connected in circuit with the primary winding of said coil and operable by said cam, said circuit breaker being mounted on said distributor block, a condenser mounted on said distributor block, means connecting one side of said condenser to one of the points of the circuit breaker, and means including a metallic plate mounted on said block for connecting the other sides of said circuit breaker and condenser to ground through said common means.

2. In apparatus of the class described, a housing, means for generating high tension current including a rotor, means for rotatably support ing said rotor including a bearing plate extending transversely of said housing, means for distributing said current to the spark plugs of an engine includin a molded distributor block and a rotatable element, the latter being mounted on and carried by the shaft of said rotor, and said block having a conductor thereon connected directly to said generating means for receiving said high tension current and projecting into spark gap relation with a conducting portion of said element, and common means for securing said bear ing plate and distributor block together and to said housing.

3. In apparatus of the class described, a source of high tension electrical current, a rotatable distributor element having insulated conducting means thereon and a distributor block having a. curved face extending atleast partially around the axis of rotation of said element in spaced relation thereto, and at least three insulated electrical conductors on said block, one of said conductors being connected to said source and the other of said conductors being adapted to be connected to spark plugs in the cylinders of an internal combustion engine, the free ends of said conductors being circularly arranged around said curved face in a single radial plane and in spark gap relation with said conducting means, whereby current is successively conducted to said other conductors from said one conductor by said conducting means during rotation of said rotatable element.

4. In apparatus of the class described, a housing having an opening in one side thereof, removable closure means for said opening, means for generating electrical current including a rotor, means for distributing said current to the spark plugs of an engine including a stationary distributor block mounted in said housing adjacent said opening, an element rotatable with said rotor, an input conductor mounted on said block and connected with said current generating means, a plurality of output conductors on said block and a conducting member rotatable with said element for successively connecting said output conductors with said input conductor, circuit breaker means mounted on the base of said block adjacent said closure means and operatively associated with said generating means, and cam means on said rotor for operating said circuit breaker means.

5. Apparatus for generating and distributing electrical current comprising means for generating electrical current including a rotor and circuit breaker means comprising a cam member on the shaft of said rotor, and means adapted to distribute said current to the spark plugs of an engine comprising an insulating distributor block, a rotatable distributor element mounted on and rotatable with said cam member, and cooperable conducting members molded in said block and element, the conducting members in said block being circumferentially spaced relative to said element and the conducting member on said element having circumferentially spaced portions for operatively successively connecting different pairs of the conducting members in said block.

6. Apparatus of the class described comprising means for generating electrical current including a rotor and means adapted for distributing said current to the spark plugs of an engine comprising an insulating distributing block having a plurality of terminals circularly arranged around the haft of said rotor, and a rotatable insulating element mounted on and rotatable with said shaft having conducting means molded therein for cooperation With the terminals of said distributor block, said conducting means extending circumferentially of said element a sufiicient distance for periodically operatively connecting one of said terminals to each of the other of said terminals during rotation of said shaft.

JAKOB R. FREI.

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