Power Steering Unit with Sealed Protective Housing

Abstract

A power-steering device intended to be fitted on a vehicle-receiving structure, such as a cradle, the device including a rack as well as at least one actuator subassembly including at least one assistance motor, one drive gear, as well as one load-bearing structure that carries the assistance motor and is arranged to support and guide the drive gear and the rack relative to one another, the device further including one containment casing that is separate from the actuator subassembly and is fonned by connecting at least one base and one bell housing, which are attached to one another by a sealed joint such that the containment casing prevents the actuator subassembly from being exposed to water splashes, dust and salt spray from the outside environment when the power-steering device is in place on the receiving structure of the vehicle.

Description

technical field [0001] The present invention relates to a power steering device for a vehicle, and more particularly to an electric power steering device. Background technique [0002] Current power steering generally includes an assembly with a number of modules corresponding to different functions added over time to improve the steering. [0003] There is thus usually a basic mechanism in a power steering to ensure the manual steering control function, said basic mechanism comprising a steering column which is driven by the steering wheel and which engages on the steering frame by means of a drive pinion, said mechanism The frame is guided in translation in the steering housing and is connected to the steering wheels by steering tie rods. [0004] There is also an auxiliary motor, usually associated with a gear reducer that enables said auxiliary motor to act on the frame or on the steering column, this arrangement thus ensuring a motorized steering control function. The...

AI Technical Summary

Problems solved by technology

[0008] However, the multiplication of constituent parts of a power steering device makes the operation of assembling said device increasingly long, complex and expensive

[0009] Furthermore, by multiplying the connections between different housings, and thus by multiplying the number of corresponding sealing rings, the possibility of installation errors and in particular damage during assembly of the device increases, which thereby increases Risk of defects occurring on the production line

[0010] Similarly, once the device is in service, the risk of subsequent failure of the device due to the multiplicity of connections between the housings, and especially the risk of leakage at one of the connections also increases

[0011] Furthermore, because water and salt spray (that is to say suspended in the air and which form for example when a vehicle is running on a snow-covered road treated with salt, or on a road located near the sea, a large amount of brine liquid drops) tend to seep into the steering gear at the interface between the housings, so known housing assemblies remain relatively susceptible to corrosion

[0012] Furthermore, the fastening screws that hold a housing to another housing are usually made of a different metal material than that of which the housing is made up (usually, screws made of steel are used to assemble aluminum housings), so that It has sometimes been observed that, in the presence of water and more for good reason in the presence of salt water (salt spray), galvanic corrosion acts at the fasteners of the housing, which may eventually lead to a weakening of the components and even to their Damage, and / or failure of the steering gear

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