Device for controlling the speed of an internal combustion engine

A device for controlling rotational speed of an internal combustion engine, the device comprising:

• a control lever movably coupled to a support element;
• a detent element associated with one of the control lever or the support element;
• a first seat and a second seat associated with the other one of the control lever or the support element;
• the control lever actuatable between:
• a first position in which the detent element engages the first seat and the internal combustion engine operates at a first rotational speed:
• and a second position in which the detent element engages the second seat and the internal combustion engine operates at a second rotational speed;
• wherein when the control lever is at any position between the first and second positions, a biasing force forces the detent element into engagement with either the first seat or the second seat to cause the control lever to automatically assume either the first or second position respectively;
• wherein the control lever is pivotably coupled to the support element so as to be pivotable about a rotation axis, the first position being a first angular position and the second position being a second angular position;
• wherein when the control lever is at any angular position between the first and second angular positions, the biasing force forces the detent element into engagement with either the first seat or the second seat to cause the control lever to automatically assume either the first or second angular position respectively;
• and
• wherein centres of the first and second seats are located along an imaginary circumference formed about the rotation axis.

A method of controlling rotational speed of an internal combustion engine, the method comprising:

• a) applying an actuation force to a control lever to move the control lever, relative to a support element, into an intermediate position between a first position in which the internal combustion engine operates at a first rotational speed and a second position in which the internal combustion engine operates at a second rotational speed;
• b) upon cessation of the actuation force, the control lever automatically assuming either the first position or the second position in response to a biasing force;
• wherein one of the control lever or the support element has a detent element associated therewith;
• wherein the other one of the control lever or the support element has a first seat and a second seat associated therewith;
• wherein in the first position, the detent element engages the first seat;
• wherein in the second position, the detent element engages the second seat;
• wherein the biasing force forces the detent element into engagement with either the first seat or the second seat when the control lever is in the intermediate position and the actuation force is ceased, thereby causing the control lever to automatically assume either the first or second position respectively;
• a wall separating the first seat and the second seat;
• and
• wherein when the control lever is in the intermediate position, the biasing force forces the wall and the detent element into contact with one another, thereby pushing the detent element into either the first seat or the second seat.

A method of controlling rotational speed of an internal combustion engine, the method comprising:

• a) applying an actuation force to a control lever to move the control lever, relative to a support element, into an intermediate position between a first position in which the internal combustion engine operates at a first rotational speed and a second position in which the internal combustion engine operates at a second rotational speed;
• b) upon cessation of the actuation force, the control lever automatically assuming either the first position or the second position in response to a biasing force;
• wherein the control lever is pivotably coupled to the support element;
• wherein step a) further comprises applying the actuation force to the control lever to pivot the control lever into the intermediate position, the intermediate position being an angular position and the first and second positions being angular positions;
• and
• wherein the biasing force has a direction that is parallel to the rotation axis.