US3018768A - Engine starting apparatus - Google Patents

Description

Jan. 30, 1962 H. THOMPSON 3,018,768

I ENGINE STARTING APPARATUS Filed Feb. 9, 1960 2 Sheets-Sheet 1 TII3 INVENTOR HOWARD H.THOMPSON M W /W ATTORNEY Jan. 30, 1962 H. H. THOMPSON 3,013,768

ENGINE STARTING APPARATUS Filed Feb. 9, 1960 2 Sheets-Sheet 2 lllllli MINI- TIE: 3

lll- I T k l INVENTOR HOWARD H. THOMPSON av W ATTORNEY United States. PatentO 3,018,768 ENGINE STARTING APPARATUS Howard H. Thompson, San Jose, Calif., assignor to FMC Corporation, a corporation of Delaware Filed Feb. 9, 1960, Ser. No. 7,633

5 Claims. (Cl. 123-185) This invention relates to engine-powered gardening machinery and more particularly relates to starting apparatus for the engines of such machinery.

An object of the invention is to provide improved apparatus for starting power gardening machines.

Another object is to provide improved starting apparatus having an advantage with respect to the length of pull required to start the engine of greater than 1: 1.

Another object of the invention is to provide an improved kick-starter fora power lawnmower, i.e., a starter enabling a person to start the engine of the lawnmower by means of a foot-actuated lever.

These and other objects and advantages of the invention will be apparent from the following description and the accompanying drawing wherein:

FIG. 1 is a partly broken away perspective of a power lawnmower having the starter of the invention operatively installed thereon.

FIG. 2 is a side elevation, partially in section, of the lawnmower of FIG. 1 and illustrates two operational positions of the starter. v p

The power lawnmower (FIGS. 1 and 2) comprises a housing or framework 12 having four wheels 14 rotatably mounted thereon, and an engine 16. The engine 16 is centrally mounted on the lawnmower framework 12 and extends a .short distance through a suitable central opening 18 in the housing. The engine includes several foot members 20, which project over the housing 12 ad jacent the opening 18 and support the engine on the framework. A bolt 22 passes through each foot member to fasten the engine to the framework 12. A handle 24 for the lawnmower is connected to the framework 12 by suitable axially aligned pivot pins such as the bolt 26 (FIG. 2).

Connected to the engine crankshaft 28 (FIG. 2) are an engine cranking mechanism 30, a flywheel 32, and a grasscutting blade 34. A nut 36 connected to the end of the crankshaft 28 retains these members in their operating positions. The engine cranking mechanism 30 is not shown in detail but comprises what is known in the art as a recoil starter and includes a cranking pulley 31.

Recoil starters used on small engines are usually provided with a pull rope which is pulled briskly by hand, to crank the engine. In close quarters or in situations where the operator is requiredto assume an awkward position, suchpull ropes cannot be operated satisfactorily. The advantage with respect to length of pull provided by the starting apparatus of the present invention permits small engines to be easily cranked even in close quarters and without liability of injury to the operator.

The pull rope or starting cable 38 of the engine 16 has one end thereof operably connected to the recoil starter 30 from which the rope extends through an opening 40 in the engine casting. The other end of the cable 38 is securely fastened to the framework 12, as by passing it through a small hole 42 in the framework and. then tying a knot 44 in it, as shown in FIG. 2. A sheave or pulley 46 engages the cable between the opening 40 and the hole 42, thus forming a loop, or bight 47 in the cable. The pulley 46 is mounted on a pin 48 in one end of a lever 50. The lever 50 is pivotally mounted on a bolt 52 which is carried in a bracket 54 welded or otherwise connected to the housing 12 ofthe lawnmower. A tread bar 56 is connected to the lever 50 at the end opposite the pulley 46.

To crank the engine 16 the tread bar 56 is depressed 3,018,768 Patented Jan. 30, 1962 2 from its initial position (FIG. 1, and phantom line position in FIG. 2) to its alternate position (solid line position in FIG. 2). Depression of the tread bar 56 causes the pulley 46 to translate or bodily move in an arcuate path around the bolt 52. In moving, the pulley causes the rapid withdrawal of the cable 38, spinning the internal mechanism of the cranking mechanism 30 so as to crank the engine 16.

The lever 50 is, of course, adapted to be operated by foot and with the disclosed arrangement the operator can with little effort, and without stooping or otherwise assuming an awkward position, impart a starting impulse to the engine. When'the operator removes his foot from the tread bar 56 the lever is automatically returned to its initial position (FIG. 1) by the action of the recoil starter 30 rewinding the cable 38.

Since the apparatus of the present invention actuates the starter by the use of a pulley engaging a bight portion 47 of the pull rope, the pulley end of the lever need travel only one half the distance to turn the cranking mechanism and therefore it attains an advantage with respect to length of pull of approximately 2:1 as compared to the 1:1 ratio provided by conventional starting devices wherein a single reach of a pull rope is withdrawn by hand. Other lever lengths and other pulley arrangements are variations which could be used to change the pressure required to operate the device and to change the ratio of the mechanical advantage attained thereby. The apparatus can be used for starting any engine of reasonable size.

While a particular embodiment of the present invention has been shown and described it will be understood that the device is capable of modification and variation without departing from the principles of the invention and that the scope of the invention should be limited only by the scope and proper interpretation of the claims appended hereto.

The invention having thus been described, that which is believed to be new and desired to be protected by Letters Patent is:

1. In a gardening machine having a frame, an engine mounted on said frame, and a cranking mechanism connected to said engine, the combination of a cable having one end thereof operatively connected to said cranking mechanism and the other end thereof fixed to the frame, and a foot-operated lever mounted for movement relative to said frame and having a portion operatively engaged with said cable intermediate said cable ends and movable along a path transverse to a line passing through said points of connection for imparting a starting impulse to the engine.

2. In a machine having an engine and an engine cranking mechanism including a starting pulley, the combination of a starting cable having one end thereof wound on said pulley and having the other end thereof fixed, a sheave engaging a bight of the starting cable between said ends, and foot-operated means mounted on said machine for bodily shifting said sheave in a direction away from the starting pulley to unwind the cable therefrom to rotate the pulley and thereby impart a starting impulse to the engine.

3. In a gardening machine having a frame, an engine mounted on said frame, and a cranking mechanism operatively connected to said engine, the combination of a starting cable having one end thereof operatively connected to the cranking mechanism and having its other end immobilized, a pulley operatively engaged with the starting cable, and a foot-operated lever connected to said pulley for translating the pulley in a manner drawing the cable from the cranking mechanism to impart a starting impulse to the engine.

4. Starting apparatus for a gardening machine having an engine mounted on the frame thereof and a cranking device connected to the engine, said apparatus comprising a foot-operated lever, a starting cable having one end thereof operably connected to the cranking device and having the other end thereof fastened to the frame, and a pulley journalled on said lever and operatively positioned to pull the cable and thereby impart a starting impulse to the engine upon foot operation of said lever.

5. In a gardening machine having a frame, an engine mounted on said frame, and a cranking mechanism operatively connected to the engine crank shaft, the combination of a starting cable having one end thereof operatively connected to said cranking mechanism and having the other end thereof fastened to said frame, a foot- References Cited in the file of this patent UNITED STATES PATENTS 1,327,942 Christie et al. Jan. 13, 1920 1,553,780 Keeler Sept. 15, 1925 2,293,322 Veach Aug. 18, 1942 2,850,003 Konle Sept. 2, 1958

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