Venting for unit containing rotating components and fluid
A venting structure for a housing containing rotating components and fluid, such as a vehicle drive unit, includes a vent receptacle that opens to an exterior of the housing. A venting duct integrally formed in a wall of a main cavity for the housing is connected at a first end to a bottom of the vent receptacle and at a second end to a portion of the main cavity that is above fluid within the main cavity for orientations between and including the housing being upright and the housing being inverted.
1 . A venting structure, comprising:
a vent receptacle that opens to an exterior of a motor housing, the vent receptacle positioned behind a shaft bearing cup that receives therein a shaft of a motor carried within the motor housing and defines a bearing bore, the motor housing having a main cavity and containing rotating components and fluid;
a vent plug within the vent receptacle, the vent plug comprising a membrane through which air permeates to equalize pressure between the main cavity and the exterior of the motor housing; and
a venting duct integrated within the motor housing and coupling the vent receptable to a recess at a bottom of the shaft bearing cup, the recess having a smaller size relative to the shaft bearing cup and defined by a lip around the bottom of the shaft bearing cup, the recess being proximate to a central point along an axis of rotation of the motor housing so that the fluid does not enter the venting duct upon rotation of the motor housing from an upright position to an inverted position.
2 . The venting structure according to claim 1 , wherein the recess is recessed relative to a depth of the bearing bore.
3 . The venting structure according to claim 1 , further comprising:
drain cutouts between the recess and the main cavity, to drain fluid from the recess back into the main cavity.
4 . The venting structure according to claim 1 , wherein the venting duct has a plurality of turns defining a labyrinthine form.
5 . The venting structure according to claim 1 , wherein a level of the fluid within the main cavity is below the bearing bore for orientations between and including the motor housing being upright and the motor housing being inverted.
6 . The venting structure according to claim 1 , wherein the vent plug is screwed or pressed into the vent receptacle.
7 . A vehicle including the venting structure according to claim 1 , wherein the motor housing is mounted on a chassis for the vehicle, the vehicle further comprising:
wheels rotatably mounted to the chassis; and
a cabin mounted on the chassis.
8 . A method of venting a motor housing containing rotating components and fluid, the method comprising:
providing a vent receptacle that opens to an exterior of the motor housing, the vent receptacle positioned behind a shaft bearing cup that receives therein a shaft of a motor carried within the motor housing and defines a bearing bore, the motor housing having a main cavity;
positioning a vent plug within the vent receptacle, the vent plug comprising a membrane through which air permeates to equalize pressure between the main cavity and the exterior of the motor housing; and
connecting a venting duct integrated within the motor housing to couple the vent receptable to a recess at a bottom of the shaft bearing cup, the recess having a smaller size relative to the shaft bearing cup and defined by a lip around the bottom of the shaft bearing cup, the recess being proximate to a central point along an axis of rotation of the motor housing so that the fluid does not enter the venting duct upon rotation of the motor housing from an upright position to an inverted position.
9 . The method according to claim 8 , wherein the recess is recessed relative to a depth of the bearing bore.
10 . The method according to claim 8 , further comprising:
providing drain cutouts between the recess and the main cavity, to drain fluid from the recess back into the main cavity.
11 . The method according to claim 8 , wherein the venting duct has a plurality of turns defining a labyrinthine form.
12 . The method according to claim 8 , wherein a level of the fluid within the main cavity is below the bearing bore for orientations between and including the motor housing being upright and the motor housing being inverted.
13 . The method according to claim 8 , wherein the vent plug is screwed or pressed into the vent receptacle.
14 . The method according to claim 8 , wherein the motor housing is mounted on a chassis for a vehicle, the method further comprising:
mounting wheels to the chassis; and
mounting a cabin on the chassis.