Cooling structure for a motorcycle transmission
A cooling structure for a motorcycle transmission includes a heat dissipation fan disposed inside a transmission housing, an inner wall of the transmission housing is provided with a flow-guiding groove directly opposite to the heat dissipation fan and a labyrinth partition adjacent to a rear side of the flow-guiding groove, an air inlet communicating with the flow-guiding groove is formed in a side wall of a front end of the flow-guiding groove, a groove bottom of the flow-guiding groove is provided with an arc-shaped flow-guiding slope, a head end of the flow-guiding slope is located at the air inlet, the flow-guiding slope is gradually inclined toward a direction close to the heat dissipation fan from the head end to a tail end, and a lower end of the labyrinth partition is spaced from a bottom edge of the transmission housing to form an air passing opening.
1 . A cooling structure for a motorcycle transmission, the transmission comprising a transmission housing, the cooling structure comprising a heat dissipation fan disposed inside the transmission housing, wherein an inner wall of the transmission housing is provided with a flow-guiding groove directly opposite to the heat dissipation fan, an air inlet communicating with the flow-guiding groove is formed in a side wall of a front end of the flow-guiding groove, a groove bottom of the flow-guiding groove is provided with an arc-shaped flow-guiding slope, a head end of the flow-guiding slope is located at the air inlet, and the flow-guiding slope is gradually inclined toward a direction close to the heat dissipation fan from the head end of the flow-guiding slope to a tail end of the flow-guiding slope, the inner wall of the transmission housing is also provided with a labyrinth partition adjacent to a rear side of the flow-guiding groove, and a lower end of the labyrinth partition is spaced from a bottom edge of the transmission housing to form an air passing opening.
2 . The cooling structure for a motorcycle transmission as claimed in claim 1 , wherein a driving pulley is disposed in the transmission housing, the transmission housing comprises an inner side cover and an outer side cover which are mutually snap-fitted, the heat dissipation fan is disposed on an end face, facing the inner side cover, of the driving pulley, the flow-guiding groove and the air inlet are both located in the inner side cover, the groove bottom of the flow-guiding groove is provided with a first via hole, and an output shaft of an engine extends into the transmission housing through the first via hole and is fixedly connected with the driving pulley.
3 . The cooling structure for a motorcycle transmission as claimed in claim 2 , wherein the groove bottom of the flow-guiding groove is provided with an annular projection arranged around the first via hole, the flow-guiding slope is arranged around the annular projection, the head end of the flow-guiding slope is located on a lower side of the annular projection, a top of the air inlet is opposite to the annular projection and a bottom of the air inlet is opposite to the head end of the flow-guiding slope.
4 . The cooling structure for a motorcycle transmission as claimed in claim 2 , wherein a front end of the inner side cover is provided with an air inlet pipe protruding relative to an outer side wall of the inner side cover, and an outlet of the air inlet pipe is the air inlet.
5 . The cooling structure for a motorcycle transmission as claimed in claim 2 , wherein an inner side wall of the inner side cover is provided with a front side groove, the heat dissipation fan is embedded into the front side groove, the flow-guiding groove is disposed at a middle of a groove bottom of the front side groove, and the tail end of the flow-guiding slope is connected to the groove bottom of the front side groove.
6 . The cooling structure for a motorcycle transmission as claimed in claim 5 , wherein the transmission housing is further provided with a driven pulley, the inner side wall of the inner side cover is provided with an air guiding protrusion located on an upper side of the labyrinth partition and connected to an upper end of the labyrinth partition, the inner side wall of the inner side cover is further provided with a rear side groove opposite to the driven pulley, and the front side groove and the rear side groove are separated by the air guiding protrusion and the labyrinth partition.
7 . The cooling structure for a motorcycle transmission as claimed in claim 6 , wherein the labyrinth partition is arc-shaped, the front side groove is substantially circular, and the air guiding protrusion and a front side wall of the labyrinth partition are coplanar with a side wall of the front side groove.
8 . The cooling structure for a motorcycle transmission as claimed in claim 4 , wherein the head end of the flow-guiding slope protrudes relative to an inner wall of the air inlet pipe, and the flow-guiding slope and the air inlet pipe are connected by an arc-shaped transition surface.
9 . The cooling structure for a motorcycle transmission as claimed in claim 1 , wherein a top of a rear end of the transmission housing is provided with an air outlet pipe and a bottom of the rear end of the transmission housing is provided with a water drain joint.
10 . The cooling structure for a motorcycle transmission as claimed in claim 2 , wherein an air guiding partition opposite to the labyrinth partition is disposed on an inner side wall of the outer side cover, an upper flanging is connected to a top edge of the outer side cover and a lower flanging is connected to a bottom edge of the outer side cover, a first upper arc-shaped partition plate and a second upper arc-shaped partition plate located at a rear side of the first upper arc-shaped partition plate are connected between an upper end of the air guiding partition and the upper flanging, a first lower arc-shaped partition plate and a second lower arc-shaped partition plate located at a rear side of the first lower arc-shaped partition plate are connected between a lower end of the air guiding partition and the lower flanging, inner concave surfaces of the first upper arc-shaped partition plate and the first lower arc-shaped partition plate are disposed toward a front side of the outer side cover, and inner concave surfaces of the second upper arc-shaped partition plate and the second lower arc-shaped partition plate are disposed toward a rear side of the outer side cover.