Wet brake system and method for a vehicle
Various systems and methods are provided for wet brake systems for vehicles. In one embodiment, a wet brake system for a vehicle includes a drive shaft, a housing including a brake compartment and a reservoir axially offset from the brake compartment along the drive shaft, a brake plate assembly including an end plate arranged within the brake compartment, a lower channel formed between the end plate and the housing and arranged at a drain end of the housing, and an upper channel formed between the end plate and the housing, opposite to the lower channel across the drive shaft. Coolant/lubricant within the housing, such as oil, may flow out of the brake compartment during conditions in which the drive shaft is rotated, and may flow into the brake compartment during conditions in which the drive shaft does not rotate or is relatively stationary.
1 . A wet brake system for a vehicle, comprising:
a drive shaft;
a housing including a brake compartment and a reservoir axially offset from the brake compartment along the drive shaft;
a brake plate assembly including an end plate arranged within the brake compartment;
a lower channel formed between the end plate and the housing and arranged at a drain end of the housing, wherein oil flows from the reservoir to the lower channel and into the brake compartment; and
an upper channel formed between the end plate and the housing, opposite to the lower channel across the drive shaft, wherein oil flows from the brake compartment to the reservoir via the upper channel, and wherein a flow rate of the oil in the upper channel is greater than a flow rate of oil in the lower channel during rotation of friction plates in the brake plate assembly.
2 . The wet brake system of claim 1 , wherein the upper channel and the lower channel are each defined at least in part by respective end surfaces of the end plate and a respective shoulder surfaces of the housing.
3 . The wet brake system of claim 1 , wherein the upper channel and the lower channel are the only fluidic connections between the reservoir and the brake compartment.
4 . The wet brake system of claim 1 , wherein the upper channel and the lower channel are arranged along a plane orthogonal to a rotational axis of the drive shaft.
5 . The wet brake system of claim 1 , wherein the upper channel and the lower channel are formed together as a single, annular channel extending around the drive shaft along an inner perimeter of the housing.
6 . The wet brake system of claim 1 , wherein a radial length between the lower channel and the drive shaft is greater than a radial length between the drive shaft and a wall of the reservoir.
7 . The wet brake system of claim 1 , wherein the brake compartment encircles an entire perimeter of the end plate, and wherein the end plate comprises a shape different than a plurality of friction plates and a plurality of separator plates of the brake plate assembly.
8 . The wet brake system of claim 1 , wherein the brake plate assembly further includes a plurality of friction plates rotatably driven by the drive shaft, where rotation of the plurality of friction plates drives oil from the brake compartment through the upper channel, the brake plate assembly further including a plurality of separator plates, wherein the plurality of separator plates alternate with the plurality of friction plates.
9 . The wet brake system of claim 1 , wherein the reservoir feeds oil to the lower channel via gravity.
10 . The wet brake system of claim 1 , further comprising at least one side channel formed between the end plate and the housing, where the at least one side channel fluidly couples the brake compartment and the reservoir.
11 . A system, comprising:
a housing partitioned by an end plate of a brake plate assembly, including a brake compartment at a first side of the end plate and a reservoir at an opposing, second side of the end plate;
a plurality of friction plates of the brake plate assembly disposed within the brake compartment;
an oil intake channel arranged to receive oil from the reservoir via gravity, wherein oil flows from the reservoir to the lower channel and into the brake compartment; and
an oil output channel opposite to the oil intake channel across a drive shaft, arranged to return the oil to the reservoir via centrifugal pumping of the oil through the brake compartment by the plurality of friction plates, wherein oil flows from the brake compartment to the reservoir via the upper channel, and wherein a flow rate of the oil in the upper channel is greater than a flow rate of oil in the lower channel during rotation of friction plates in the brake plate assembly.
12 . The system of claim 11 , wherein the oil intake channel and the oil output channel are each defined at least in part by an end surface at the second side of the end plate and a respective shoulder of the housing, where the respective shoulder is adjacent to the end surface and spaced apart from the end surface, and wherein an inlet of the oil output channel and the outlet of the oil input channel are equidistant from a drive shaft.
13 . The system of claim 12 , wherein a width of the oil output channel between the end surface and the respective shoulder is less than a length of the oil output channel in a direction orthogonal to a rotational axis of the plurality of friction plates.
14 . The system of claim 11 , wherein a rate of the centrifugal pumping is based on a rotational speed of the drive shaft.
15 . The system of claim 11 , wherein a volume of oil within the brake compartment is based on a rotational speed of the drive shaft.
16 . The system of claim 11 , wherein a volume of oil within the brake compartment is an inversely proportional function of a rotational speed of the drive shaft.
17 . A method, comprising:
flowing a coolant/lubricant from a reservoir formed within a wet brake housing at a first side of a brake plate assembly through a lower channel to a lower end of a brake compartment arranged between the brake plate assembly and the wet brake housing, wherein oil flows from the reservoir to the lower channel and into the brake compartment; and
returning the coolant/lubricant from an upper end of the brake compartment to the reservoir via an upper channel formed between an end plate of the brake plate assembly and the wet brake housing, wherein oil flows from the brake compartment to the reservoir via the upper channel, and wherein a flow rate of the oil in the upper channel is greater than a flow rate of oil in the lower channel during rotation of friction plates in the brake plate assembly.
18 . The method of claim 17 , further comprising: driving the coolant/lubricant through the brake compartment, across surfaces of a plurality of friction plates of the brake plate assembly, from the lower end of the brake compartment to the upper end of the brake compartment.
19 . The method of claim 18 , wherein driving the driving the coolant/lubricant through the brake compartment from the lower end to the upper end includes pulling the coolant/lubricant from the lower end of the brake compartment to the upper end of the brake compartment via rotation of the plurality of friction plates of the brake plate assembly.
20 . The method of claim 19 , wherein a rate of the returning of the coolant/lubricant from the upper end of the brake compartment to the reservoir via the upper channel is based on a rotational speed of the plurality of friction plates.