Speed reducer for electric power steering system
AssigneeHl Mando Corporation
InventorKyeongho Lee
Life of this patent
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Abstract
A speed reducer for an electric power steering system according to an embodiment of the present disclosure includes a gear housing, a plurality of air flow passages, and check valves. The gear housing accommodates a worm shaft and a worm wheel. The plurality of air flow passages is formed in the gear housing and connects the outside of the gear housing and a sealed space formed in the gear housing. The check valves are respectively disposed in the plurality of air flow passages.
Claims18
A speed reducer for an electric power steering system, the speed reducer comprising:
- a gear housing configured to accommodate a worm shaft and a worm wheel;
- a plurality of air flow passages formed in the gear housing and configured to connect an outside of the gear housing and a sealed space formed in the gear housing;
- and
- a first check valve and a second check valve respectively disposed in different ones of the plurality of air flow passages,
- wherein the first check valve is configured to allow air to flow only from the sealed space to the outside of the gear housing;
- wherein the second check valve is configured to allow air to flow only from the outside of the gear housing to the sealed space;
- wherein at least one of the check valves comprises:
- a body portion having a tubular shape,
- a stepped portion formed at one side of the body portion,
- a duckbill portion formed at another side of the body portion and having a slit;
- and
- wherein said at least one of the check valves further comprises a cover extending from an end of the body portion to cover the slit such that the cover blocks foreign substances while permitting press e-responsive air flow.
A speed reducer for an electric power steering system, the speed reducer comprising:
- a gear housing accommodating a worm shaft and a worm wheel;
- a sealed space formed in the gear housing;
- a plurality of air flow passages formed in the gear housing and connecting an outside of the gear housing and the sealed space;
- and
- check valves respectively disposed in the plurality of air flow passages;
- wherein a first check valve, which is one of the check valves respectively disposed in the plurality of air flow passages, allows air to flow to the outside of the gear housing from the sealed space,
- wherein a second check valve, which is another one of the check valves respectively disposed in the plurality of air flow passages, allows air to flow to the sealed space from the outside of the gear housing,
- wherein at least one of the check valves is a duckbill valve including a body portion, a stepped portion, and a duckbill portion having two inclined surfaces and a slit, and the duckbill portion further includes a cover configured to cover the slit and extending or protruding from an end of the body portion.
Dependencies are inferred from the claim text.