Multi-speed transmissions and methods for shifting multi-speed transmissions for marine vessels

A multi-speed transmission for a marine vessel, the multi-speed transmission comprising:

• first and second gears each engageable to transmit rotation between an input shaft and an output shaft therethrough;
• first and second clutches actuatable to engage the first and second gears, respectively;
• first and second pressure sensors that measure first and second pressures within the first and second clutches, respectively;
• and
• a memory system storing a first pressure threshold range;
• a controller that controls actuation of the first and second clutches, wherein the controller is configured to perform a first shift from the first gear to the second gear by actuating the second clutch and, after a first delay, de-actuating the first clutch, and wherein the controller is further configured to:
• receive the first and second pressures measured by the first and second pressure sensors, respectively, and determine a first shift pressure at which the first and second pressures are substantially equal while performing the first shift;
• access the first pressure threshold range stored in the memory system;
• compare the first shift pressure to the first pressure threshold range;
• and
• adjust the first delay when the first shift pressure is outside the first pressure threshold range.

A method for making a multi-speed transmission for transmitting rotation from an input shaft to an output shaft for a marine vessel, the method comprising:

• providing first and second gears each engageable to transmit rotation from the input shaft to the output shaft;
• providing first and second clutches actuatable to engage the first and second gears, respectively;
• positioning first and second pressure sensors to measure first and second pressures within the first and second clutches, respectively;
• and
• configuring a controller to:
• control actuation of the first and second clutches such that a first shift from the first gear to the second gear is performed by actuating the second clutch and, after a first delay, de-actuating the first clutch, and a second shift from the second gear to the first gear is performed by actuating the first clutch and, after a second delay, de-actuating the second clutch;
• receive the first and second pressures measured by the first and second pressure sensors, respectively, determine a first shift pressure at which the first and second pressures are substantially equal while performing the first shift, and determine a second shift pressure at which the first and second pressures are substantially equal while performing the second shift;
• access first and second pressure threshold ranges stored in the memory system;
• and
• compare the first shift pressure to the first pressure threshold range and adjust the first delay when the first shift pressure is outside the first pressure threshold range, and compare the second shift pressure to the second pressure threshold range and adjust the second delay when the second shift pressure is outside the second pressure threshold range;
• wherein the controller is configured to determine the first shift pressure every time the multi-speed transmission shifts from the first gear to the second gear, and to determine the second shift pressure every time the multi-speed transmission shifts from the second gear to the first gear;
• wherein at a given rotation of the input shaft the first gear causes the output shaft to rotate in a first direction at a first rotational speed and the second gear causes the output shaft to rotate in the first direction at a second rotational speed that is faster than the first rotational speed.