US890815A - Reversing device for explosive-engines. - Google Patents

Description

No. 890,815. PATENTED JUNE 16, 1908. c. M. STROUD.

REVERSING DEVICE FOR EXPLOSIVE ENGINES.

APPLICATION FILED MAY 9, 1907- CHARLES M. STROUD, OF HASTINGS, MINNESOTA.

REVERSING DEVICE FOR EXPLOSIVE-ENGINES.

Specification of Letters Patent.

Application filed May 9, 1907.

Patented June 16, 1908.

Serial No. 372,774.

To all whom it may concern:

I I Be it known that 1, CHARLES M. SrRoUD, a citizen of the United States, residing at Hastings, in the county of Dakota and State of Minnesota, have-invented certain new and useful Improvements in Reversing Devices for Explosive-Engines; and I do hereby dcclare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the. art to which it appertains to? make and use the same.

My invention relates to electric ignition mechanism for explosive engines, and particularly to those employing adjustable timers, by means of which the time of the spark may be advanced or retarded.

The invention has for its object to provide means whereby when the-timer is adjusted in a direction to increase the advance or lead of the spark beyond a predetermined extent, the sparking circuit will be broken, and to provide in connection therewith means for automatically restablishing the sparking circuit when the engine speed falls slow a predetermined point.

To the above ends the invention consists of the novel devices and combinations of devices hereinafter described and defined in the claims.

In the accompanyin drawings which illustrate the invention, li e characters indicate like parts throughout the several views.

. Referring to the drawings, Figure 1 is a view in side elevation, illustrating my invention applied to a two-cycle engine. Fig. 2 is a front elevation of the said engine, some parts being sectioned. Fig. 3 is a detail showing the timer in plan; and Fig. 4 is a detail in lyi orizontal section, taken on the line 00 x of Of the parts of the en ine, it is for the purpose of this case desira le to note only the cylinder 1, the crank casing 2, crank shaft 3, the sparking plug 4, and the timer shaft 5, which latter isjournaled in bearings 6 and 7 on the cylinder casting and is driven from the crank shaft 3 through a pair of miter gears 8, all of which parts are of the usual or any suitable construction.

- A timer of the standard or any suitable construction maybe em loyed, and of the parts thereof the numera 9 indicates the insulated case section, and the numeral 10 the Inetallicpart of the said case, the latter having a hand'piece 11 by means of which the case may be adjusted around the ax-is of the shaft 5 for the purpose of advancing or retardingthe spark. The rotating internal contact of this timer is, of course, carried by the timer shaft5 in the usual way. To hold the case 9-10 in diflerently adjusted positions, 'a spring pressed pin 12 in the hand piece 11 is arranged to cooperate with a notched segment 13 on the upper bearing 7.

In the drawings, the invention is shown as applied-in connection with a sparking coil 14,

primary circuit wires 15, and secondary cir- V cuit wire 16. The secondary wire 16 conmeets the secondary of the sparking coil to one of the'electrodes of the sparking plug 4, in the usual way, and one of the primary wires 15 extends to a contact 17 on the insulated case section 9, which contact 17 is connected in. the usual Way to a contact within the,case of the timer with which the rotary contact of the timer cooperates in the usualway. A'battery or source of electrical en-' ergy 18 is shown; as interposed in the other rimary wire 15, and this wire is connected y a wire 19 or other suitable means to a pair of ground contacts 20 and 21. The contact 20 15 secured to but insulated from the upper bearing 7, and the free end thereof is arranged to cooperate with a contact 22 that is set into the insulated case section 9 and, as shown, is in the form of an extension of the metal case section 10.

The ground contact 21 is in the form of a metal ring that'surrounds the timer shaft 5, but is insulated therefrom by an insulating bushing 24 and is held against rotation by a ried by the timer shaft 5. The balls 26 are so arranged that when the on he s eed is below a-predetermined'point, t ey W1 1 drop.

into engagement with the annular contact 21 under the action of gravity. In the preferred arrangement, however,-the governor balls are connected by a light sprin 28which assists gravity in throwing the ba against the contact 21 when the engine speed drops below a predetermined point.

The contact 22, which is carried by the case of the timer, is so located with res ect to the cooperating contact 20 that it 'wil main I tain engagement therewith under all adjust ments of the case section required to give the various lead or advance and retardation to the spark, required for diflerent engine speeds carry the contact 22 out of engagement with the contact 20, thereby breaking the igniter circuit at that oint. When this is 'done, while the engine is at high speed and the governor balls 26 are thrownloutward as shown.

in Fig. 2, the igniter circuit will be broken at two points, to-wit, between the contacts 20 and 22, and the contact 21 and governor balls 26. Attention is here called to the fact that the said overnor balls in the arrangement illustrated in the drawings also actas contacts for engagement with the contact ring 21.

When the igniter circuit is broken as just I stated, the production of spark will, of course,

be temporarily interrupted, so that the speed of the engine will be decreased until that certain predetermined speed is reached where the combined action of gravity and of the spring 28 will throw the balls 26 against the contact ring 21, and thereby closethe primary of the igniter circuit. v

The osition in which the case 'of the timer is set w en adjusted as just above described, throws the s ark producing periods so far in advance of t e inward extreme movement of the piston that the explosion produced under slow speed is sufiicie'nt to overcome the momentum of the parts and, hence, reverse the engine. This reversal of the engine, it will also'be noted, is automatic and takes place only after the s eed of the engine has been reduced to a point where it' is perfectly safe to reverse the engine. The speed at which the engine would be thus automatically re- -versedmay, of course, be varied and should be varied according to the load. carried by the engine.

. The term timer is herein used in a broad sense to include any kind of mechanism for controlling or timing the spark of the ignition mechanism. These. timerswhen designed engine comprising an engine driven timer shaft, a timer made up of two principal parts, one of which is carried by saidshaft and the other of which is in the form of a case'and is mounted for adjustment around the-axis of said shaft, which case is composed of interlapped metallic and insulating materials, an ignition circuit including the metallic portion of said timer case and a relatively fixed contact,-whic h fixed contact is adapted to be engaged with the insulating portion of said timer case to break the circuit and to be engaged with the interlapped metallic portion thereof to close the circuit, and an engine driven centrifugal governor having circuit connections a'rranged to reestablish the igni tion circuit through said timer when the cu gine falls below-"a predetermined speed, substantially as described. f I

3. The combination with anexplosive engine, of electric ignition mechanism com ')ris ing a timer having contacts arrangec to break the ignition circuit when said timer is adjusted for an excessive amount of lead, an en ine driven timer shaft carrying the movable contact of said timer, a centrifugal governor carried by said timer shaft, and arelatively fixed annular contact and circuit con-- -nections cooperating with said governor and arranged to reestablish the ignition circuit through said timer when the engine speed fallsbelow a predetermined point, substan tially as described.

In testimony whereof I afiix my signature 105 inpresence of two witnesses.

CHARLES M. STROUD.

Witnesses:

MALIE Honn, F. D. MERUHANT.

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