US2117230A

US2117230A - Engine starting apparatus

Info

Publication number: US2117230A
Application number: US89503A
Authority: US
Inventors: Herbal A Thornburg; James V Brown
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1936-07-08
Filing date: 1936-07-08
Publication date: 1938-05-10
Anticipated expiration: 1955-05-10

Description

2 Sheets-Sheet l May 10, 1938. H. A. THORNBURG ET AL ENGINE STARTING` .QPPARTUSl Filed July e, 1936 May 1938- v H. A. THORNBURG ET AL 2,117,230

ENGINE STARTING APPARATUS Filed July 8, 1956 2 Sheets-Sheet 2 Patented May 10, 1938 UNITED STATES PATENT OFFICE ENGINE STARTING APPARATUS aware Application July 8, 1936, Serial No. 89,503

5 Claims.

This invention relates to apparatus for starting an internal combustion engine and particularly to the type of apparatus which comprises an electric motor and a pinion driven by motor and movable axially into mesh with the fly-wheel or other gear of the engine to be started. In this type of apparatus the pinion is withdrawn from the flywheel gear after the engine has been started.

It is one of the objects of the present invention to prevent engaging the motor-driven pinion with the engine gear in case the engine is running prior to moving the pinion into engagement therewith.

In the disclosed embodiment of this invention the present object is accomplished by providing a part adapted to make substantially noiseless contact with an end face of an engine flywheel and to be moved in response to contact with the moving ywheel into such position as to positively stop movement of the motor pinion into engagement with the flywheel gear.

The present invention is adapted for any sort of motor vehicle propelled by an internal combustion engine and is particularly useful on passenger busses of the type where the engine is located on the side or at the rear of the vehicle and so far from the drivers seat that the operation of the engine when idling is not audibly perceptible. It occasionally happens that the operator, believing that the engine has stopped, whereas in fact it is idling, will operate the starter control button causing the starter pinion to mesh with the flywheel gear. The engagement of the starter pinion with the flywheel gear while the engine is running produces a disagreeable noise and is damaging to the gear teeth. Such noise or darnage is avoided by the use of the present invention.

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

In the drawings:

Figure 1 is in part a longitudinal sectional View of the starting apparatus embodying the present invention and in part a wirin-g diagram;

Figures 2 and 3 are sectional Views taken respectively on the lines 2--2 and 3-3 of Figure 1;

Figures 4, 5, and 6 are fragmentary side views partly in section of the engine starter drive, showing the same in various positions; and

Figure 7 is in part an end View of the pinion and clutch assembly and in part a sectional view of the clutch, the end view being taken in the ,A direction of the arrow A1ct of Figure 6, the sectional View being taken on the line 1 1 of Figure 6.

Referring now to Figure 1, numeral 29 designates the electric motor comprising afield winding 2 I an armature 22 and brushes 23 and 24, the latter of which is grounded at 25. This motor drives the shaft 26 which is supported by bearings carried by the frame of the motor. The left end frame is not shown, but it will be understood to be attached to the left-hand end of the field frame 21 which carries the field winding 2|. The right end frame or gear housing of the motor is designated by numeral 28, and it carries a bearing 29 for the right-hand end of the shaft 26.

The shaft 26 is provided with longitudinal splines 3U which cooperate with longitudinal splines 3l provided in the sleeve 32 of the inner member or clutch cam 33 of an overrunning clutch.` This clutch comprises also a driven member or shell 34 and a series of rollers 35 eachl of which is located between the inner cylindrical surfaces of shell 34 and a cam surface 33a which is not concentric with the shell. The surfaces 33d are so arranged with respect to the shell 34 that, as the clutch inner member 33 rotates clockwise as viewed by the arrow 36 in Figure '7, clockwise rotation will be imparted to the shell 34. Obviously the shell 34 may overrun in a clockwise direction with respect to the inner driving member 33 when one Views it as shown in Figure '7. The clutch inner member 33 carries a bearing bushing 31 which is journaled on the reduced end portion 26a. of the shaft 26. The portion 26a, supportsa bearing bushing 38 press-fitted into the hub of a starting motor pinion 39 which is adapted to move axially along the shaft portion 26a into mesh with the iiywheel gear 40 of the engine to be started. The pinion 39 is drivingly connected with the shell 34 by providing the latter with an annular boss 4| into which are provided a series of depressions, each adapted to receive an end portion of a tooth of the pinion 39 when the pinion is fixed to the shell 34, as shown in Figure 1. To secure the pinion 39 to the shell 34 the pinion is provided with an annular flange 42 which is passed through a central orifice in the shell 34 and is riveted over against the shell 34, as indicated at 43.

This overrunning clutch and pinion assembly is moved along the shaft 26 by means of a pinion meshing means including shifter sleeve 50 provided with an annular groove 5| for receiving pins or studs 52 located on diametrically opposite sides of the sleeve 50 and carried by spaced arms 53 of al lever 54 pivoted upon a rod 55 carried by the frame 28. The rod 55 is surrounded by a coil spring 56, one end 51 of which bears downwardly against the frame 28, as indicated by the arrow 51a and the other end 58 of which bears in the direction of the arrow 59 against a pin 58 carried by the lever 54. Counterclockwise rotation of the lever 54 causes the sleeve 58 to move toward the right, as shown in Figure 1. The sleeve 58 has a central bore 6| which has a sliding t with the shaft 26 and has a part 62 provided with a central bore E3 having a sliding iit with respect to the sleeve 32. Between the right-hand end of part 52 and the left-hand end of a washer 64 surrounding the sleeve 32 and bearing against the clutch cam 33, there is located a coil spring 65 which normally is somewhat compressed. Spring 65, therefore, forces the part 62 a denite distance away from the washer 64 and clutch cam 33. The separation of the parts 62 from the parts 64 is limited by a wire split ring 66 which is snapped into a groove provided by the sleeve 32 and which bears against a beveled surface 81 provided on the left-hand end of the part 62. The part 62 is joined with the main part of the sleeve 58 by an arcuate web 68 shown best in Figure 2. This web 68 is spaced from the shaft 26 suiiiciently to permit assembling the split ring 66. Quite obviously, motion of the sleeve toward the right as eiected by counterclockwise rotation of the lever 54 will cause the motion to be imparted through the spring 65 to the clutch and pinion assembly thereby causing the pinion 39 to move into engagement with the engine gear 48.

The lever 54 is moved in a counterclockwise direction by direct manual operation or by the electromagnetic means shown diagrammatically in Figure 1. 'I'his electromagnetic means comprises an electromagnet having two windings 18 of relatively fine wire and 1| of relatively coarse wire. These windings surround a non-magnetic tube 12 which provides a guide for the movement of a magnetizable armature 13 toward a stationary magnetizable core member 14 also located within the magnetic field which is created by current passing through these windings. The core 14 is attached to the magnetizable discs 15 which are in contact with a magnetizable shell 16 and in contact also with m'agnetizable discs 11 and 18 which are h'eld by the sleeve 12 concentric with respect to the armature 13.

The starting motor 28 is energized by current from a storage battery 88 which is grounded at 8| and which is connected by wire 82 with a starter switch contact 83. Contact 83 is connected by a movable Contact 84 with a stationary contact 85 which is connected with winding 1| and with the series field 2| of the starting motor. The contact 84 is insulatingly supported by a tubular metallic rivet 88 which is slidable upon a rod 81 which extends through the core 14 and is guided thereby. The rod 81 carries a washer 88 against which the tubular rivet 86 is urged by spring 89 located between a washer 98 xed to the rod 81 and a washer 9| loosely mounted on the rod 86. The washer 98 is held against the left end face of core 14 by a spring 92 which surrounds a stud 93 carried by a fixed part 94 and projects into an axial. bore 94 in the pin 81. The spring 92, therefore, serves to maintain the contact 84 out of engagement with contacts 83 and 85, and the righthand end of plunger 81 in such position as to be normally engaged by the left-hand end of core 13. The winding 18 is grounded at 18.

To start the engine, the operator closes the switch ||8 thereby causing the current to flow from the battery through the switch and through the windings 10 and 1| and back to the ground connection 18a. Current will also flow from the battery through the switch I8, winding 1|, starting motor 20, and back to the battery through the ground connections 25 and 8|. The electromagnet will be energized suiciently to cause the armature 13 to move toward the left in order to cause that counterclockwise rotation of the lever 54 and that axial movement of sleeve 58 which will move the motor pinion 39 into mesh with the engine gear 48. During this movement of the armature 13, it will engage the rod 81 to cause it to move toward the left and the contact 84 to be engaged with the contacts 83 and 85 under yielding pressure afforded by the spring 89. When this occurs the motor will receive current from the battery and the shaft 26 will rotate and the pinion 39 will drive the engine gear 48 in such direction as to cause the engine to be started. After the engine has been started the operator releases the push-button switch I8 thereby causing the electromagnet to be deenergized, whereupon the lever 54 is moved clockwise into its original position due tol the action of the spring 56, and the pinion 39l is withdrawn from the engine gear 48. The armature 13 having been withdrawn from the rod 81, the spring 92 moves the rod 81 back to its normal position thereby disengaging the contact 84 from the contacts 83 and 85, whereupon the motor 28 is disconnected from the battery 88 and the motor stops.

When the contact 84 engages the contacts 83 and the winding 1| of coarse wire will be short circuited so that a greater amount of current will flow from the battery to the starting motor than before. At the time contact 84 engages with contacts 83 and 85 to short circuit the winding 1| the air gap between the core 14 and armature 13 is relatively small and, therefore, the magnetic force produced by the coil 18 alone is sufficient to hold the armature 13 in its attracted position.

Should the pinion 33 collide with the end faces of the teeth of the flywheel gear 48 before going into mesh, motion of the armature 13 will not cease due to the fact there is yielding connection aiorded by the spring 85 between the sleeve 58 and the pinion and clutch assembly. After the pinion 39 engages the end faces of the teeth of the flywheel gear 48, the armature 13 will continue to move toward the left and the sleeve 58 toward the right. While the spring 65 is being compressed beyond its initial stage of compression, the switch contact is being engaged with the contacts 83 and 85. When this engagement occurs, the motor will be connected with the battery and will cause the pinion teeth to be brought into mesh registration with the spaces between the teeth of the engine gear 48. At the instant meshing registration occurs, the spring 65 will be released quickly to move or jump the pinion 39 into mesh with the engine gear 48.

Should the pinion 39 fail to come out of mesh with the engine gear 48 after the engine starts, the spring 92 is still free to move the contact 84 away from the contacts 83 and 85 due to the fact that the slots |84 in links |83 provide thelostmotion connection between the lever 54 and the armature 13.

The means for preventing the meshing of the motor pinion with the engine gear after the engine becomes self-operative and the pinion has been demeshed therefrom, will now be described with particular reference to Figures 1, 4, 5, and 6. This means comprises a tubular cup-shaped part |20 having a tubular sleeve |2I/journaled on the part 62 of the sleeve 59 of the pinion meshing means, and having an annular flange |22 adapted to engage the left end face of the flywheel |23 which carries the gear 40. The part 62 carries diametrically opposed screw pins |24, each of which is received by a somewhat T-shaped slot |25 provided in the tubular sleeve 2| of the tubular part |29. The head of this T-shaped slot |25 is a somewhat triangular opening dened by wall portions |25 which are oblique or inclined to the axis of the pinion. The stem or elongated por tion of the slot is indicated by numeral |21, and is of a length such that the pinion may be meshed with the engine gear while part |20 is pressed against an end face of the engine gear, provided that the pin i2@ remains in alignment with the elongated slot portion |21. Where the stem or elongated portion |21 joins the head portion defined by oblique wall portions |29, the metal of sleeve |2| provides stop shoulders |28 each of which is adapted to receive pin |24 depending on which direction the sleeve |20 is rotated with respect to the sleeve `59.

Normally each pin |24 rests in the apex of the head portion of the slot |25 and between the oblique wall portions |26, and is caused to be moved into that position by spring |30 located between a shoulder |3| of the sleeve 59 and a washer |32 surrounding the sleeve 59 and bearing against the left end of the sleeve 2 Therefore, while the engine is at rest, the pinion 39 may be meshed with the engine gear 40 without hindrance by the cup-shaped member |20 since, during this meshing movement, the pin |24 will move into the stem portion |21 of the slot 25 and finally into the position shown in Figure 5, when the pinion 39 is fully meshed with the engine gear 40. During the cranking of the engine the flange |22 of the cup-shaped member |20 will bear against the left face of the engine flywheel |23, but such engagement will be practically noiseless.

If the operator attempts to mesh the motor pinion 39 with the engine gear 40 while the engine is running the tubular, cup-shaped part |28 will be rotated due to the frictional engagement of the end face of the ywheel |23 and flange |22 of the part |20 thereby causing the slots |25 in the sleeve 2| to be shifted relative to the pins |24 carried by the sleeve y5|), one way or the other depending on the direction of the rotation of the cup-shaped member |29. Figure 6 shows the condition which will obtain if, looking in the direction of the arrow 'la in Figure 6, the rotation of the ywheel |23 is counterclockwise. Quite obviously, the rotation of the tubular, cupshaped part |29 will be clockwise. Therefore, the slot |25 nearest the observer of the view shown in Figure 4 will move upwardly into the position shown in Figure 6, and the lowermost portion of the two shoulders |28 provided by the metal of the sleeve |2| adjacent the slot |25 will provide a stop for the pin |24. Since the pin |24 can move no further toward the right than is shown in Figure 6, the shifter sleeve U and the clutch and pinion assembly can be moved no further toward the right. The clutch and pin assembly is arrested in its movement and is limited` to a' position wherein the pinion 39 is still out of engagement with the left end facesof the gear teeth of the flywheel gear 40, as shown in Figure 6. In this way motion of the pinion into engagement with the engine ilywheel gear is positively arrested when the operator attempts to mesh these gears While the engine is running. Upon release of the operating lever 54 the spring 5E restores it and the other parts of the pinion meshing means to normal position shown in Figure l. During this return movement, the end ange |22 of the tubular part |29 leaves the end face of the engine gear 23 and each slot part |21 returns to alignment with each pin |24 due to the camming action between each pin |24 and each inclined wall surface |26 caused by pressure exerted by the spring |30.

While the 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. Engine starting apparatus comprising, in combination, an electric motor, a pinion driven by the motor and slidab-le axially into mesh with a gear of the engine to be started, means to move the pinion into mesh with the engine gear, and means responsive to rotation of the engine gear for positively blocking movement of the pinion into mesh with the engine gear whilethe engine is running, said last mentioned means comprising a locking sleeve adapted to be rotated by the engine gear into locking position to prevent movement of the pinion toward the engine gear.

2. Engine starting apparatus comprising, in combination, an electric motor, a pinion driven by the motor and slidable axially into mesh with a gear of the engine to be started, means to move the pinion into mesh with the engine gear, a part movable against an end face of the engine gear and adapted to be rotated thereby, means for transmitting movement from the pinion meshing means to said part to cause the latter to be pressed against an end face of the engine gear before the pinion starts to mesh with the engine gear, and devices for interconnecting the pinion meshing means and said part, said devices being so constructed and arranged as normally to permit such a relative movement between the pinion and part that the pinion may be meshed with the engine gear while the part is pressed against the engine gear and to prevent said relative movement in case the engine gear is rotating before the pinion is meshed therewith` 3. Engine starting apparatus comprising, in combination an electric motor, a pinion driven by the motor and slidable axially into mesh with a gear of the engine to be started, means to move the pinion into mesh with the engine gear, a tubular part surrounding the pinion and pinion meshing means and movable against an end face of the engine gear to be rotated thereby, means for transmitting motion from the pinion meshing means to said port to cause the latter to be pressed against an end face of the engine gear before the pinion starts to mesh with the engine gear, and devices for interconnecting the pinion meshing means and said part and provided respectively by said means and part, one of said devices being a laterally extending pin and the other a member having a slot for receiving the pin, said slot having an elongated portion extending longitudinally of the axis of the pinion whereby normally to permit such a relative movement between the pinion and tubular part that the pinion may be meshed with the engine gear while the part is pressed against the engine gear, said slot providing a stop shoulder which is moved into alignment with the pin in case the tubular part is rotated by the engine gear face prior to the meshing of the pinion With the engine gear.

4. Engine starting apparatus comprising, in combination, an electric motor, a pinion driven by the motor and slidable axially into mesh with a gear of the engine to be started, means to move the pinion into mesh With the engine gear, a tubular part surrounding the pinion and pinion meshing means and movable against an end face of the engine gear to be rotated thereby, yielding means for transmitting motion from the pinion meshing means to said part to cause the latter to be pressed against an cnd face of the engine gear before the pinion starts to mesh with the engine gear, and devices for interconnecting the pinion meshing means and said part and provided 'respectively by said means and part, one of said devices being a laterally extending pin and the other a member having a slot for receiving the pin, said slot having an elongated portion extending longitudinally of the axis of the pinion whereby normally to permit such a relative movepin to alignment with the elongated portion of the slot when the pinion meshing means returns to normal position.

5. Engine starting apparatus comprising, in combination, an electric motor, a pinion driven by the motor and slidable axially into mesh with` a gear of the engine to be started, means to move the pinion into mesh with the engine gear, tubular part surrounding the pinion and pinion meshing means and movable axially against an end face of the engine gear to be rotated thereby, a slot provided by the tubular part including an elongated portion extending longitudinally of the axis of the pinion a pin extending laterally from the pinion meshing means and into said slot, a spring for transmitting motions from the pinion meshing means to the tubular part thereby causing one end wall of the slot of the tubular part to bear normally against said pin whereby normally to maintain an end of the tubular part closer to the engine gear than the pinion, said elongated slot portion permitting the pinion to be meshed with the engine gear while the tubular part is pressed against an end face of the engine gear, said slot providing a stop portion which is moved into alignment with the pin in case the tubular part strikes the engine gear while rotating whereby to prevent contact between the pinion and engine gear while the engine is running, and said slot providing a surface inclined to the axis of the pinion and located between the stop shoulder and an end of said slot, said inclined slot portion cooperating with the pinion under pressure exerted by said spring to restore the alignment between the pin and the elongated portion of said slot when the pinion meshing means returns to normal position.

HERBAL A. THORNBURG. JAMES- V. BROWN.