阅读说明：本技术 齿轮箱组件 (Gear box assembly ) 是由 M·阿普尔亚德 于 2018-06-29 设计创作，主要内容包括：披露了一种用于电动动力辅助转向设备的齿轮箱组件,该齿轮箱组件包括：齿轮箱壳体,该齿轮箱壳体容纳蜗杆轴和蜗轮,该蜗杆轴承载蜗杆齿,该蜗轮具有一组蜗轮齿,蜗杆轴相对于壳体在距马达最近的一端由主轴承组件支撑,并且在距马达最远的一端由尾部轴承组件支撑,并且蜗轮由输出轴支撑,该输出轴具有从齿轮箱组件取力的至少一个端部。第一支点装置定位在主轴承组件的第一侧,该第一支点装置仅对蜗轮转矩的第一方向的蜗杆轴齿载荷的轴向分量起反作用,并且第二支点装置定位在主轴承组件的相反的第二侧,该第二支点装置仅对蜗轮转矩的第二方向的蜗杆轴齿载荷的轴向分量起反作用,第一支点和第二支点与主轴承组件的接触点限定了轴线,主轴承组件能够绕该轴线枢转。(A gearbox assembly for an electric power assisted steering apparatus is disclosed, the gearbox assembly comprising: a gearbox housing containing a worm shaft carrying worm teeth and a worm gear having a set of worm gear teeth, the worm shaft being supported relative to the housing at an end closest to the motor by a main bearing assembly and at an end furthest from the motor by a tail bearing assembly, and the worm gear being supported by an output shaft having at least one end which is weighted from the gearbox assembly. A first fulcrum arrangement is positioned on a first side of the main bearing assembly, the first fulcrum arrangement reacting only to an axial component of the worm shaft tooth load in a first direction of the worm gear torque, and a second fulcrum arrangement is positioned on an opposite second side of the main bearing assembly, the second fulcrum arrangement reacting only to an axial component of the worm shaft tooth load in a second direction of the worm gear torque, contact points of the first and second fulcrums with the main bearing assembly defining an axis about which the main bearing assembly is pivotable.)

1. A gearbox assembly for an electric power assisted steering apparatus, the gearbox assembly comprising:

a gearbox housing containing a worm shaft carrying worm teeth and a worm gear having a set of worm gear teeth,

the worm shaft being supported relative to the housing by a main bearing assembly at an end nearest the motor and by a tail bearing assembly at an end furthest from the motor, and the worm gear being supported by an output shaft having at least one end that takes force from the gearbox assembly,

the main bearing assembly including an inner race defining a bearing inner race fixed to the worm shaft such that it cannot move axially relative to the worm shaft, an outer race defining a bearing outer race, and a plurality of bearings running between the two races,

the assembly being arranged such that the worm shaft is pivotable about one or more axes in the vicinity of the main bearing assembly, thereby enabling bilateral tooth flank contact of the teeth of the worm with the gear teeth,

further comprising a first fulcrum means positioned on a first side of the main bearing assembly and a second fulcrum means positioned on an opposite second side of the main bearing assembly, the first fulcrum means reacting only to an axial component of a worm shaft tooth load in a first direction of worm wheel torque and the second fulcrum means reacting only to an axial component of a worm shaft tooth load in a second direction of worm wheel torque, the contact points of the first and second fulcrums with the main bearing assembly defining an axis about which the main bearing assembly is pivotable.

2. A gearbox assembly according to claim 1, wherein said first fulcrum means may comprise a pair of rigid elements, each rigid element having an axis substantially parallel to the axis of the worm shaft and two opposite regions located at each end of said axis defining an end of said element, said elements being positioned substantially equidistant on either side of the worm shaft axis in a common plane parallel to both the worm shaft and the worm wheel axis, and wherein the first end of each element bears against the gearbox housing or against a component connected to the gearbox housing, and the second end of each member bears against the outer race of the first bearing assembly or against a component connected to the outer race of the first bearing assembly, and wherein the first and second ends of each element can be inclined at a small angle relative to the surface against which they rest.

3. A gearbox assembly according to claim 1 or claim 2, wherein the second fulcrum means comprises a pair of elements having an axis substantially parallel to the worm shaft, the elements being positioned substantially equidistant on either side of the worm shaft axis in a common plane parallel to the axes of both the worm shaft and the worm gear, and a first end of each element bearing on the gearbox housing or on a component connected to the gearbox housing and a second end of each element bearing on the outer race of the first bearing or on a component connected to the outer race of the first bearing, and wherein the first and second ends of each element are tiltable by a small angle relative to the surface on which they bear.

4. A gearbox assembly according to any preceding claim, comprising a counter plate fixed to the gearbox housing and positioned on the side of the first bearing assembly nearest the motor, the counter plate providing a rigid extension of the gearbox housing, the first fulcrum means applying an axial load of a first direction of worm gear torque to the counter plate.

5. A gearbox assembly according to any preceding claim, wherein each of said elements comprises a dowel or a ball bearing.

6. A gearbox assembly according to any preceding claim, wherein at least one element of each pair of elements is positioned in a complementary bore such that the element is free to slide along the bore under certain defined circumstances.

7. A gearbox assembly according to any preceding claim, wherein the first fulcrum means is located adjacent a face of the first bearing assembly which is proximal to the second bearing means, and wherein the second fulcrum means is located adjacent a face of the first bearing means which is distal from the second bearing means.

8. A gearbox assembly according to any preceding claim, wherein a common plane of said pair of elements of said first fulcrum arrangement coincides with or is close to and substantially parallel to a common plane of said pair of elements of said second fulcrum arrangement.

9. A gearbox assembly according to any preceding claim, wherein the common plane of the pair of elements of the first and second fulcrum means coincides with or is close to a plane parallel to both the worm shaft axis and the worm wheel axis and passing through the nominal contact points of the worm shaft teeth and the worm wheel teeth where the so-called pitch circle diameter of the worm shaft meets the so-called pitch circle diameter of the worm wheel.

10. A gearbox assembly according to any preceding claim, wherein the apparatus comprises support means for supporting the worm shaft first bearing outer race, the support means being rigid in terms of radial forces acting on the first bearing assembly and flexible in an axial direction so as not to support axial forces acting on the first bearing assembly.

11. A gearbox assembly according to claim 10, wherein the support means supporting the first bearing assembly is flexible with respect to the tilting moment acting on the first bearing assembly.

12. A gearbox assembly according to claim 11, wherein said support means comprises a flexible plate having a main portion with a substantially central bore closely fitting on the outer diameter of the outer race of said main bearing assembly and having legs on each side of said main portion, said legs being substantially parallel to each other and depending in one direction from generally adjacent two corners of said main portion such that said legs are each located to one side of said main portion.

13. A gearbox assembly according to any preceding claim, wherein a first end of said pair of elements comprising exclusively said first or second fulcrum means rests solely on a respective one of two separate spring loaded adjustment means mounted to said gearbox housing or to a component rigidly attached to said housing and capable of automatically eliminating axial free play between the end of said element and the surface against which the end of said element rests.

14. A gearbox assembly according to claim 13, wherein each of said adjustment means comprises a generally cylindrical piston slidably assembled into a bore in the gearbox housing or a component rigidly attached thereto, and wherein the axis of said bore is at an angle to the axis of the element resting on the piston, and wherein a generally wedge-shaped portion of material has been removed from the piston such that a flat face is formed against which the element rests, and wherein the wedge-shape of the removed material is such that the flat face is substantially at right angles to the axis of the element and is of sufficient length to allow a first end of the element to remain against the flat face as the piston moves along the bore a distance of a few millimetres, and wherein a spring urges the piston along the bore in a direction such that the flat face urges the element towards the first bearing, and wherein a combination of the angle of the bore and a coefficient of friction between the piston and the bore and between the piston and the first end of the element is combined to prevent the piston from moving against the force of the spring by the compressive force of the element.

15. A gearbox assembly according to claim 13 or claim 14, wherein the first ends of said pair of elements comprising exclusively said first or second fulcrum means each individually rest on a fixed surface that is part of, or a component rigidly attached to, the gearbox housing.

16. A gearbox assembly according to claim 15, wherein the ends of one or more or all of said elements are spherically curved or cylindrically curved.

17. A gearbox assembly according to any preceding claim, wherein one or more or all of the elements of said first and second pivot arrangements are substantially enclosed in complementary apertures in said gearbox housing or in a component rigidly attached thereto.

18. A gearbox assembly according to any preceding claim, wherein each bearing assembly comprises an inner race carrying an inner race of bearings, an outer race carrying an outer race of bearings, and a set of bearings.

19. The gearbox assembly of claim 18, wherein said first bearing assembly outer race is sandwiched between rigid bearing holders such that one end of each member of said pair contacts an outer face of said rigid holders.

20. A gearbox assembly according to claim 19, wherein axial forces acting through the outer ring of the bearing assembly are transferred to each of the two bearing element holders by respective flexible rings positioned in grooves in the rigid holder, one of said rings being positioned in contact with either end face of the outer ring of the bearing or with an intermediate component.

21. The gearbox assembly of claim 20, wherein each ring comprises an elastomeric ring.

22. A gearbox assembly according to claim 19, wherein the cross-sectional area of the groove in the rigid holder varies circumferentially around the worm shaft axis in a manner that allows the resistance to tilting of the first bearing assembly relative to the bearing holder to be less in a first plane that includes the worm shaft axis than in a second plane that also includes the worm shaft axis and is at right angles to the first plane, which is also parallel to the axis of the worm wheel.

23. A gearbox assembly according to claim 22, wherein the circumferential variation in cross-sectional area of said groove is obtainable by having a variable size chamfer or radius at one or more edges or corners of said groove.