US1759435A - Ignition system - Google Patents

Description

May 20, 1930. w. A. CHRYST IGNITION SYSTEM Filed Jan. 14, 1926 Patented May 20, 1930 UNITED STATES PATENT OFFICE WILLIAM A. CHRYST, OF DAYTON, OHIO,

ASSIGNOR, BY IESNE ASSIGNHEITTS, TO

CORPORATION OF DELAWARE IGNITION SYSTEM Application filed January 14, 1828. Serial No. 81,192.

This invention relates to ignition timers for internal combustion engines and has among its objects .the provision of novel means for adjusting an engine operated circuit interrupter angularly relative to the en ine driven cam which operates it.

urther objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanyin drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a plan view of an ignition device with the distributor head and the rotor removed;

Fig. 2 is a sectional view taken along the line 22 of Fig. 1;

Fig. 3 is a detail section taken along the line 3-3 of Fig. 1, showing the eccentric adjusting device; and

Fig. 4 is a diagrammatic view showin the various circuit connections for the ignition device.

Referring to the drawings, the numeral 20 designates a housing for mounting the ignition unit on the engine. A fragment of this housing is illustrated in Fig. 2. A timer housing 21 is supported by the housing 20 and is provided with a partition 22 having an apertured centrally extending portion 23 in which the bearing 24 is contained. A retainer plate 25 rests on one surface of the partition 22 and holds the bearing 24 within said portion 23.

A drive shaft- 26 is journaled at its lower end in a bearing supported in the housing 20 (not shown on the drawing), while the opposite end of said shaft has a reduced portion 26 journaled in the bearing 24. A spacing collar 24", substantially equal in diameter to the inner race of the bearing 24, surrounds the reduced portion 26" and rests on said inner race. A timer cam 27 is received by the reduced portion 26. The

timer cam 27 comprises a main body portion having the desired number of lobes for operating the circuit interruptersfour being shown in the present drawings. The cam 27 has an extension of less diameter than the said main bodyportion, and this extension is provided with a flat portion 28.

The end of the reduced portion of drive shaft 26 is provided with longitudinally extending slots 29, and with a recess having a a conical wall 30. A screw 31 threadedly engages the shaft 26 and has a groove for receiving a retainer ring 32 which holds a bushing 33 in position around the screw. The bushing 33 has a conical outer surface which conforms to the conical surface 30 so that when the screw 31 is screwed into the shaft, the bushing 33 will exert pressure upon the slotted end of the drive shaft and will expand the same against the inner wall of the 5 cam, thereby clamping the cam rigidlyon the drive shaft.

A rotor 34 has a recess provided in its hub portion, said recess conforming to the shape of the reduced extension of the cam 27. The 70 flat portion 28 of said extension causes the rotor to be rotated with the cam, and also provides for locating the rotor only in the correct position upon the cam.

, 'On the face of the rotor, opposite the cam 27, there is carried a conducting strip 34, which extends from the center portion of the hub of said rotor toward the outer end thereof. Adjacent the outer end of the rotor there is provided a conducting sleeve 35 which is embedded in a recess formed in the rotor and is in electrical connection with the strip 34". Sleeve 35 carries a slidable cup-shaped member 36, the closed end of the cup extending outwardly toward the conducting strip 34. A spring 37 is interposed between the cup 36 and the rotor 33. In the closed end of the cup 36 is an aperture for receiving the head of the rotor button 38, said head being carried The outer edge of the timer rotor when slot 57, the longer sides centric to the screw 53.

slot 62 is provided in the by the cup in such a manner that 38 is swiveled on said cup.

the button housing 21 is provided with anannular groove for receiving a corresponding annular extension formed on the distributor head 40. The head 40 is provided with ears 41 for receiving hooks 42 having at their lower ends hook portions extending into notches provided by lugs 43 formed on the timer housing. Thus, the hooks 42 tend to hold the distributor head 40 on the timer housing 21.

The distributor head 40 is provided with a central, high-tension terminal 44 having a spring-pressed terminal button 45 held in engagement with the contact strip 34 of the the distributor head 40 is in position on the timer housing. A plurality of high-tension terminals 45 are arranged in a circular row about the central terminal 44 in spaced relation, these terminals 45 being engaged successively by the rot-or button 38, as the rotor is operated by the drive shaft 26. Upon the retainer plate 25 there is placed a stationary plate 50, held in-position in the timer housing by means of screws 51. A plate 52 is pivoted upon the plate by a' screw 53 which extends through an aperture in said plate 52, adjacent other end of the plate, ear 54 angularly' there is provided an the stationary contact 56. A lock nut is provided on said shank 55 for securely holding said shank in adjusted position relative to the ear 54.

The plate 52 is provided with an elongated of which are con- The slot 57 receives a locking screw 58, which has a screw-threaded connection with the stationary plate 50,

so that when the screw 58 is tightened the plate 52 is prevented from moving relative to the plate 50.

Between the pivot screw 53 of plate 52 and the slot 58, the plate 52 is provided with a slot 59, the long sides of which extend oblique- 1y to the long sides of the slot 58. A collar extends through the slot 59 and rests upon the surface of the stationary plate 50. This collar 60 is secured to the plate 50 by a rivet 61,.ecceritric to said collar. A screw-driver collar 60, which permits the said collar 60 to be rotated by means of a screwdriver, about its eccentric rivet 61 in order to move the plate 52 relative to the plate 50 when the screw 58 is loosened.

The housing 21 contains a plurality of interrupters. Two interrupters are shown in the drawings, one being supported and carried by the stationary plate 50, the other by the movable plate 52. Each interrupter in cludes a stationary contact and a cooperat- --.i ng movable contact mounted upon a contact arm.

. to the web portion arranged thereto, said ear supporting the screw-threaded shank 55 of tween the two interrupter arms Each movable contact arm is provided by a member of channel-shaped cross section" having flanges 65', and a web portion 66. The arm 69 is insulatingl pivoted upon astud 67 attached to the p ate 50. A washer 68, retained upon the stud 67by means of a cotter pin, holds the contact arm 69 in position on said stud. A cam follower'72, which is adapted to engage the cam .27 is secured to the web 66 by a rivet 70 and to the flanges 65 by a rivet 71. The freeend of the contact arm 60 carries a contact point 73 which is adapted to engage the stationary contact 74 attached to a screw'7'5 threaded through an upright ear 76 formed on the stationary plate 50. f

A blade spring 77 has one end anchored 66 of the contact arm 69 so as to be in electrical connection therewith. The blade 77 passes around the stud 67 and is secured'to and electrically connected with a conducting plate 78 by a nut 79 and a screw I stud 80, electrically connecting the blade one end thereof. At the spring 81 of an interrupter arm 82 to the conlductor 78. The blade spring 81 is connected to the arm 82 in the same manner that spring blade 7 7 is connected with the arm 60.

The Contact arm 82, which is of the same construction' as the contact arm 69, is pivoted upon the adjustable plate 52 by a stud 83 attached to the plate 52 and is insulated from said plate. Arm 82 carries a contact point 84 which is adapted to engage with StfltlODt ary contact 56.

. The drawings show the improved interrupter adjusting device applied to a timer having two interrupters operated alternately. In order to obtain the proper angular relation between the interrupter so that circuit interruptions may be obtained at proper intervals, the screw 58 is loosened and the plate 52 is shifted relative to the stationary plate 50. Assuming for example that the cam 27 is operating in a direction as indicated by the arrow 100 and that the contact arm 82 is operated so as to separate and 84 too soon after the contacts 7 3 and 74 have been separated, the eccentric collar 60 is turned in a clockwise direction in order to move the plate 52 in a clockwise direction about its pivot 53. This adjustment moves the cam follower 85 in the direction in which the cam 27 is rotating, thus retarding the time of ircuit interruption by said contact arm 82. \Vhen the proper angular relation beis obtained,

the collar 60 is held in properly adjusted position by the screw-driver used to turn it 58 is tightened by another while the screw screw-driver to secure the plate 52 to the to be operated to close the circuit between the source of current and the ignition coil. When the switch is closed, current will flow from the sourc of current through the primary winding of coil 93 to the terminal 80 and thence through conductor plate 78 to the contact arms 69 and 82, via the springs 78 and 81, respectively, which are connected in parallel to the terminal 80.

The cam 27 operates the contact arms 60 and 82 alternately to complete the ignition primary circuit and then to interrupt it in order to produce the required number of sparking impulses. In the illustrated embodiment of the invention, for each revolution of the four-lobe cam 27, eight sparking impulses will be generated by the coil 93, and these impulses are distributed by the cooperation of the rotor contact 34 with the various spark plug terminals 45 of the distributor head 40.

As known to those skilled in the art, the life of the timer is prolonged and the timer may be operated more satisfactorily at high speeds by using two alternately operated in terrupters instead of one. Since the use of two interrupters permits the use of a cam having one-half the number of lobes required of a cam operating a single interrupter, a cam of relatively small dimensions may be designed to give longer duration of current flow through the ignition primary ,circuit, and thus to permit the current in the coil to attain the desired high value at high engine speeds.

It will be understood that the present invention is not limited in its application to the particular timing apparatus shown in the drawings, but that it may be applied to other timers, for example, to a timer having a single interrupter or to one having two interrupters operated simultaneously.

\Vhile the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. An ignition device comprising, in combin'ation, a housing; a plate rigidly secured in said housing; a second plate pivotally secured to the first-mentioned plate and having an elongated slot; a pair of circult interrupters in said housing, each including a stationary contact and a cooperating, movable contact arm, one of said interrupters being mounted on the first-mentioned plate, the other on' the second plate; a cam engaging the movable contact'arm of each interrupter and adapted to operate them;an eccentric member carried by the first-mentioned plate and extending through the elongated slot of the second plate, said member being operable to adjust the second plate relative to the first plate, whereby the angle between the oint of contact of the interrupter arms an the cam may be adjusted as desired.

2. An ignition device comprising, in combination, a housing; a plate rigidly secured in said housing; a second plate pivotally secured to the first-mentioned plate and havingan elongated slot; a pair of circuit interrupters in said housing, each including a stationary contact and a cooperating, movable contact arm, one of said interrupters being mounted on the first-mentioned plate, theother on the second plate; a cam engaging the movable contact arm of each interrupter and adapted to operate them; an eccentric member carried by the first-mentioned plate and extending through the elongated slot of the second plate, said member being operable to adjust the second plate relative to the first plate, whereby the angle between the point of contact of the interrupter arms andthe cam may be adjusted as desired; and means carried by the first plate and adapted to clamp the second plate to lock it in the adjusted position.

3. An ignition device comprising, in combination, a housing; a plate rigidly secured in said housing; a second plate pivotally secured at its one end to the said rigid plate, and having an elongated slot'whose longer sides are concentric to the pivot, of the plate and an elongated aperture, intermediate the slot and the pivot of the plate, the longer sides of said aperture being angular with the longer sides of the slot a circuit inter rupter carried by each respective plate; a cam for operating said interrupters; a rotatable adjusting member carried by the rigid plate and having an eccentric "head extending into the aperture of the pivoted plate for adjusting the pivotedplate relative to the rigid plate; and locking means extending through the slot of said pivoted plate and secured to the rigid plate for locking the two plates in adjusted position.

4. An ignition de ice comprising, in combination, a housing member; a circuit interrupter comprising cooperating contacts, a niovable asupport carrying one of the contacts,

' n follower for operating the movact support; a cam within the housing member in order to adjust the cam follower angul'arly relative to the cam, said means comprising an eccentric rotatably suported by one of said members and received y an elongated recess in the other member; and means for retaining said plate member in the desired position of adjustment.

5. A11 ignition device according to claim 4, in which the eccentric is provided by a disc which is eccentrially pivotally connected with the housing member and which is received by an elongated recess in the plate member.

In testimony whereof 1 hereto aflix my signature. v,

' WILLIAM A. CHRYST.

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