US1825388A

US1825388A - Ignition apparatus

Info

Publication number: US1825388A
Application number: US364891A
Authority: US
Inventors: John T Fitzsimmons
Original assignee: Delco Remy Corp
Current assignee: Delco Remy Corp
Priority date: 1929-05-21
Filing date: 1929-05-21
Publication date: 1931-09-29
Anticipated expiration: 1948-09-29

Description

Sept. 29, 1931. 1

J. T. FITZ'SIMMONS IGNITION APPARATUS Filed May 21, 1929 Patented Sept. 29, 1931 UNITED STATES IGNITION APPARATUS Application filed Kay 21,

5 will start more readilyif the time of sparking impulses is advancedbeyond the normal high degree for engine operation. After the engine has become self operative, however, and its temperature hasrisen, more efli cient engine operation is obtained if the time of sparking impulse is again adjusted so that it will fall within the proper range for normal engine operation. i

It is among the objects of the present invention to provide means adapted automatically to adjust the ignition timer in accordance with variations in temperature, so that the time of sparking impulses will be advanced substantially at comparatively low temperatures.

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

In thedrawings:

Fig. 1 is a longitudinal sectional view taken through the ignition device.

Fig. 2 is a plan view of the ignition device with the distributor head and rotor removed.

Fig. 3 is a transverse sectional view taken along the line 3-3 of Fig. 1.

Fig. 4 is a view similar to Fig. 3, but showing a modified form of thermostatic element.

Referring to the drawings, the ignition device is shown comprising a cup-shaped casing, or housing 20, having a shank portion 21 which is adapted to be rotatably supported in a bearing 22 provided in the crank case of the engine. The shank 21 is hollow and provides a bearing for the drive shaft 23 of the ignition device. said drive shaft having a pinion 24 secured at its outer end, which is adapted to be drivingly connected with a gear 25 rotated by the engine and mounted preferably on the cam shaft of the engine.

A tubular cam shaft 26, having a cam'portion 27 provided with six lobes, as shown in 1929. Serial No. 364,891.

PATENT OFFICEIIFQ JOHN T. FITZSIMMONS, or ANDERSON, INDIANA, ASSIGNOR T0 DnLco-RENY. conron A- fi TION, 0F ANDERSON, INDIANA, A CORPORATION or DEL W RE Q Fig. 2, telescopically fits overa reduced end i of the drive shaft 23, said cam shaft being rotatably supported upon the drive shaft. The lower end of said cam shaft rests upon an annular flange 28 formed on said drive shaft.

ed also to rotate the cam shaft 26 relative to the drive shaft 23 in order to obtain read justments of the time of sparking impulses in accordance with variations in the speed of the engine. This speed governor comprises a supporting plate 30 secured to the annular flange 28 of the drive shaft so that said plate 30 will rotate with said drive shaft. Posts 31 are carried by the plate 30 at diametrically opposite points, said postsproviding means pivotally supporting centrifugal weight ele ments 32. These weight elements 32 engage a disc 33 which is drivingly connectedrwith the cam shaft 26 and which carries posts 34:, as shown in Fig. 1. One of said posts 34 extends into an elongated slot 35 provided in the plate'30. whereby the; rotation of 'the disc 33 relative to the plate 30 is limited to the length of said slot; A spring 36 is interposed between each set of posts 3134. The Weight members 32 when moving outwardly under centrifugal force will rotate disc 33 relative to the plate 30 and consequently the cam shaft-26 will be moved rotatably'relative to the drive shaft 23, thus theangular relation between the drive shaft 23 and' the cam shaft 26 is altered by the centrifugal governor operating in response tovariations in engine speed. 1 v

An annular shoulder--38 is provided in the annular wall of the housing20, said shoulder: supporting a plate 39 which carries a plate" 37 upon which is mounted the circuit interrupter mechanism of the ignition device. This circuit interrupter mechanism comprises a movable contact 40' and a stationary contact 41, the former being secured to'the free end of the contact arm 42 which is pivotally supported in an insulating manner by'the pin A speed controlled governor connectsthe;

43 carried by plate 37. A rubbing block 44 secured to the contact arm 42 intermediate its ends is adapted to be engaged by the cam 27. The rubbing block 44 is secured to the contact arm 42 by a rivet 45, which also at taches one end of the spring conductor 46 to said contact arm 42, the opposite end of said spring conductor 46 being secured to a terminal plate 48 insulatingly supported within the timer housing. A wire 49 connects the terminal 48 with one foil of a condenser '50, the other foil being in electrical connection with the plate 37 through a bracket 51 which also supports the condenser .50 in the housing 20. Terminal 48 is in electrical connection with the terminal 52 "which extends outside the timer housing 21 and is insulated therefrom in any suitable manner. The stationary contact '41 :is carried on an angular earfSS formed on the plate =54, which is pivotally supported by the pivot pin 43, 'said plate .54 being adjustably secured to the supporting plate :39. Screws 55secure thesu-p- ;plate 39 to the housing 20, as shown 2.

The speed governor described heretofiore, automatically adjusts the ignition timer to varythe time of sparking impulses inaccordance with variations in engine speed. Means have also been provided for adjust-ing the timer manually to vary the time of sparking impulses, said means including a lever '60 rota'tably supported upon the shank portion 21 of the ignition "distributor unit. One end of the lever has an elongated slot 61 wthrough which-extends the shank portion 62 of a screw '63 which threadedly engages the crank case of the engine. Screw 68 is surrounded by acupvshaped ihousing64 in which there :is provided a spring 65, said spring being interposed bet-ween the head of screw 63 and "the bottom flange in housing '64 and yie'ldab'ly urg-ingsaid housing '64 the lever 60, thus providing a drag upon said lever whereby-accidental operation thereof :is substantially prevented.

.Acup-shaped member 66 is secured to the lever 60 by rivets 67, said cup-shaped memher having -a-central aperture through which the shank 21 of the ignition device extends. On the shank 21 ofsaid ignition=clevice there is provided a split sleeve-68 havingclamping provisions 69, which, when tightened, is adapted to securely clamp the sleeve 68 in position upon the shank 21. lVithin the cupshaped member 66 *there :is provided a bimetallic temperature controlled element 70, inthe form ofa helical coil the outer end of said-element being secured to the cup-shaped member 66 by a rivet 71, the inner end of said member being secured to the sleeve 68 by a rivet '72. The bi-lnetallic coil 70operati-vely connects the lever 60 with theshank 21 of the ignition device inasmuch as lever -60 has secured thereto the cupshaped member 66 to which one end of the coil is anchored, while the shank 21 has secured thereto the sleeve 68 to which the other end of the coil 70 is attached. From this it may be seen that manual rotation of lever 60 will rotate the housing 20 relative to the drive shaft 23 and thus the contact arm 42 with its rubbing block 44 carried in the housing 20 will be rotated relative to the cam 27 secured to the drive shaft 23. This angular adjustment of the contact arm 42 relative to the cam 27 will vary the time of sparking impulse for the engme.

The slot 61 in the lever 60 limits the movement of said lever. Ordinarily the ignition unit will be set at the pmperposition relative to the said lever so that ordinarily when the lever '60 is moved tofull retarded position. the distributor 20 will be in a position fully to retard the spark. If the engine temperature is low, however, the thermostatic or oi-metallic coil 70 will be aflected by temperature to move the ignition distributor housing :20 and its shank 21 relative to the lever 60 so that the contact arm 42 is moved relative to the cam 27 to advance the time of sparking impulses, which, as has been described, facilitates engine starting when said engine is cold. As soon as the temperature of the engine begins to rise, the thermostatic element or bi-metallic coil 70 will be affected by said rising temperature automatically to rotate the timer housing '20 relative to the lever 6050 that the normal angular relation between these two elements will again be established and thus the time of sparking impulse maybe 'controlled throughout a range best adapted for normal engine operation.

If a readjustment between the shank 21 and the thermostatic element 70 is necessary, the clamping device '69 may be loosed, which permits relative rotation between the shank 21 and the sleeve '68 for adjustment purposes.

In theiFi g. 4 a modified form of thermostatic element is shown. Here a tightly wound strip of metal in the form of a spiral is provided in the cup-shaped member 66, one end of the coil being secured to the said member by a rivet 81, the other end being attached to the sleeve 68 by a rivet 82. The strip of metal 80 may be aluminum or any alloy such as substantially 20% nichrome, 80% iron, which will have a substantially large temperature coefficient and will provide movement between

elements

66 and 68 in response to temperature variations.

From the aforegoing it may be seen that the present ignition device may be adjusted to vary the time of sparking impulses for the engine, manually by the operation of lever 60, automatically in accordance with the speed of theengine by the speed governor and automatically .in accordance with the temperature of the engine by the thermostatic devices or 80.

While the form of embodiment of the present 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. Apparatus for controlling the timing of the ignition of an internal combustion engine comprising, in combination, a housing; a circuit interrupting device carried in said housing; a cam for operating said device; a manually operable lever; and a bi-metallic, temperature controlled member in the form of a helical coil, having one end thereof secured to the lever, the other end anchored to the housing, whereby the housing may be adjusted manually by the lever to adjust the position of the circuit interrupting device relative to the cam for varying the time of sparking impulses said temperature controlled member automatically adjusting the angular relation between the housing and the lever in accordance with temperature changes.

2. Apparatus for controlling the timing of the ignition of an internal combustion engine comprising in combination, a housing havin ashank portion adapted to be supported rotatably by the engine; a circuit interrupter carried in the housing; an engine driven cam for operating said interrupter; a manually operable lever rotatably supported on the shank portion of the housing; a bi-metallic coil surrounding the shank portion and having one end anchored to the lever, the other end to said shank portion, said coil providing for the manual operation of the housing by the lever to adjust the interrupter relative to the cam for spark timing purposes, and also providing for automatic adjustments between the lever and shank portion of the housing, to alter their angular relation in accordance with temperature changes.

3. Apparatus for controlling the timing of the ignition of an internal combustion engine comprising in combination, a housing; a shank on said housing, adapted to be secured rotatably upon the engine; a circuit interrupter supported in said housing; an engine driven cam for operating said interrupter; a sleeve adapted to be clamped to the shank; a manually operable lever; means for limiting the movement of said lever; a cup-shaped retainer attached to the lever substantially coaxially of the shank which extends through an aperture in the retainer; a bi-metallic member in the form of a helical coil supported Within said retainer the outer end of said coil being secured to the annular wall of the retainer, the inner end of the coil being secured to the sleeve signature.

JOHN T. F ITZSIMMONS.