The slower the engine is turning, the lower the spool sits on its shaft. This shaft fits though the block and the govenor arm is connect to part of that shaft that is exposed to the outside of the block. As the governor spool pushes up on the governor crank, the crank turns clockwise turns the governor arm clockwise which pulls the throttle to the idle position via a long solid link.
Now we know that the governor closes the throttle, then what opens it? The governor spring is what opens the throttle. If you did not have a governor, the governor spring would pull the throttle shaft all the way open and keep it there. Hydraulic governor. The governor system is like a cruise control system in an automobile. It maintains the speed of your lawn mower or outdoor power products. A carburetor that's incorrectly adjusted is a common cause of poor engine idling that results in hunting and surging.
Fortunately, most lawnmowers have two screws that allow you to adjust the carburetor yourself. Then slowly adjust the screws tighter or looser in turn until the mower runs and idles smoothly. To control engine speed, a mechanical governor uses gears and flyweights inside the crankcase to detect changes in the load and adjusts the throttle accordingly. This closes the throttle, limiting the air-fuel released into the engine. When the engine load increases, the crankshaft spins more slowly.
What is the working principle of governor? A centrifugal governor is a specific type of governor with a feedback system that controls the speed of an engine by regulating the flow of fuel or working fluid, so as to maintain a near-constant speed. It uses the principle of proportional control. How does a governor control speed? It is basically the amount of work that the engine should perform for a certain distance. In the case of a mower, it is the grass height it needs to cut.
When you switch the lawn mower on and move it through the grass, the springs that are controlling the governor and the load will interact and some tension will form between them to balance them out.
Different parts within the governor system will then step in in different ways to establish a balance, either by reducing or increasing the speed. The balance will continue, until you switch off the mower. Once you witch off the motor, the spring that controls the governor will then pull the throttle to a wide-open position, and the mechanism stops working. The mechanism of operat3ion will differ with the type of governor your mower uses, which we will outline below.
In order to control the speed of the engine , the mechanical governor type will use flyweights and gears in its crankcase.
These will detect the load changes, and then adjust the throttle accordingly. For instance, when you are mowing relatively short grass or working on a very even terrain. The crankshaft will spin faster when the load is smaller, and slower when the work is more — all controlled by the governor.
When the load is lighter and the crankshaft spins faster, it will put greater pressure on the crank and governor cup. This eventually forces the throttle to close and reduce the fuel and air the engine gets. If the load is higher, the crankshaft will move slowly, which results in the flyweights relaxing and the throttle to open.
Pneumatic governors regulate speeds through using air pressure. They do this through a plastic or metallic air vane, which will sense any changes to air pressure around the flywheel.
It has the advantage of being easier to repair, as the parts are easy to access and the overall design of the system is simpler. Like the mechanical type, it will incorporate the use of one or two springs, which pulls it in an open position. When the load becomes less and the speed of the engine increases, the air that enters the flywheel will also increase. That leads to the governor blade pulling the throttle forward and close it, so that the engine remains in a steady speed limit.
0コメント