CN113581036A

CN113581036A - Gear box for vehicle seat adjusting mechanism

Info

Publication number: CN113581036A
Application number: CN202110483697.2A
Authority: CN
Inventors: 米尔恰·纳波; 多依娜·纳波; 伊莱亚娜·达恰·纳波; 伊万·纳波
Original assignee: Fisher and Co Inc
Current assignee: Fisher and Co Inc
Priority date: 2020-05-01
Filing date: 2021-04-30
Publication date: 2021-11-02
Anticipated expiration: 2041-04-30
Also published as: CN113581036B; DE102021204240A1

Abstract

The present invention relates to a gearbox for a vehicle seat adjustment mechanism. A gear box for a vehicle seat adjustment mechanism according to the principles of the present invention includes a first portion and a second portion. The first portion includes a first body defining a first longitudinal recess and a first peripheral recess in fluid communication with the first longitudinal recess. The first body includes a concave first curved surface. The second portion includes a second body defining a second longitudinal recess and a second peripheral recess in fluid communication with the second longitudinal recess. The second body includes a convex second curved surface. The second curved surface has an equal and opposite curvature compared to the first curved surface. In the assembled configuration, the first curved surface and the second curved surface are in contact, the first longitudinal recess and the second longitudinal recess cooperate to define a longitudinal passageway, and the first peripheral recess and the second peripheral recess communicate to define a peripheral receptacle.

Description

Gear box for vehicle seat adjusting mechanism

Cross Reference to Related Applications

This application claims benefit of U.S. provisional application No.63/019054 filed on day 1, month 5, 2020. The entire disclosure of the above application is incorporated herein by reference.

Technical Field

The present invention relates generally to a gear box assembly for a vehicle seat adjuster, and more particularly to a bidirectional self-centering box for an orthogonal gear transmission (e.g., an envelope-type or helical-type orthogonal gear transmission) used in adjusting a longitudinal position of a vehicle seat.

Background

This section provides background information related to the present invention and is not admitted to be prior art by this section.

Vehicles such as automobiles are often equipped with seat adjuster mechanisms that primarily can adjust the height, inclination, and/or longitudinal position of the driver seat and/or passenger seats to accommodate occupants of different sizes and heights and to provide a comfortable seating position to accommodate occupant preferences. Such seat adjusters may be manually or electrically operated.

The electrically operated seat adjuster is driven by an electric motor whose specifications are directly related to the torque that the electric motor must provide to produce the required movement. Thus, if a fairly high reduction gear ratio can be obtained in a very limited space, a smaller and faster electric motor can be used to provide the same level of mechanical power required for the required function. Electric motors used in certain applications that have increased speed and are capable of transmitting a certain level of torque require a limited reduction gear ratio but are in a very compact size space.

Electric motor-driven adjustment devices offer various advantages over manual adjustment devices. User comfort may be improved. The electric motor-driven adjustment device also provides an electrical interface that automates the electric motor-driven adjustment device, for example, bringing the seat to a desired state under the control of a controller of the vehicle that can automatically control the motor. While electric motor-driven adjustment devices offer benefits, packaging remains a problem in many seats.

Typically, the electrically operated seat length adjuster is actuated by an occupant controlled switch and includes a bi-directional electric motor mounted centrally or intermediately between a pair of track assemblies of the vehicle seat that rotates two flexible drive shafts extending outwardly from the motor to two gearbox blocks fixedly mounted within each upper or inner track assembly. Each gear box block includes a worm gear or worm screw gear drive assembly having a drive member actuated by a flexible drive shaft and a driven member integral with an internally threaded spindle nut.

Each spindle drive assembly includes the rotatable spindle nut already mentioned which threadably receives a lead screw extending longitudinally along and secured to the lower or outer track assembly. By means of these two drives, the rotational movement of the electric motor is orthogonally offset in order to move the upper rail linearly forward/backward along the spindle screw axis relative to the lower rail. The vehicle seat is attached to a frame supported by a pair of movable upper rails of the seat arranged parallel to each other, while a pair of lower rails is fastened to the vehicle chassis. Typically, two drive shafts, a gear box, a lead screw and a drive nut are employed in an electric length adjuster drive driven by only one bi-directional electric motor, one set for each seat track assembly.

Disclosure of Invention

This section provides a general summary of the invention, and is not a comprehensive disclosure of all features, either full or characteristic of the invention.

A gear box for a vehicle seat adjustment mechanism according to the principles of the present invention is provided. The gearbox includes a first portion and a second portion. The first portion includes a first body. The first body defines a first longitudinal recess and a first peripheral recess in fluid communication with the first longitudinal recess. The first body includes a first curved surface. The first curved surface is concave. The second portion includes a second body. The second body defines a second longitudinal recess and a second peripheral recess in fluid communication with the second longitudinal recess. The second body includes a second curved surface. The second curved surface is convex. The second curved surface has an equal and opposite curvature compared to the first curved surface. In the assembled configuration, the first curved surface is in contact with the second curved surface. In the assembled configuration, the first longitudinal recess communicates with the second longitudinal recess to define a longitudinal passage. In the assembled configuration, the first peripheral recess communicates with the second peripheral recess to define a peripheral receptacle.

In one implementation, both the first curved surface and the second curved surface define (i) a portion of an ellipsoidal surface, (ii) a portion of a conical surface, or (iii) a portion of a spherical surface.

In one implementation, both the first curved surface and the second curved surface define a portion of an ellipsoidal surface. The ellipsoidal surface has a first radius in a range of 190mm to 200mm and a second radius in a range of 240mm to 250 mm.

In one implementation, both the first curved surface and the second curved surface define a portion of a conical surface. The conical surface defines an average opening angle in the range of 165 ° to 172 °.

In one implementation, both the first curved surface and the second curved surface define a portion of a spherical surface. The spherical surface has a radius in the range of 190mm to 200 mm.

In one implementation, one of the first and second portions includes a frustoconical protrusion extending from a respective one of the first and second curved surfaces. The other of the first and second portions includes a frustoconical receptacle defined by a respective one of the first and second curved surfaces. In the assembled configuration, the frustoconical receiver receives the frustoconical protrusion.

In one implementation, one of the first and second portions further includes an annular protrusion extending from a respective one of the first and second curved surfaces. An annular projection is disposed around the base of the frustoconical projection. The annular projection is coaxial with the frustoconical projection. The other of the first and second portions further includes an annular recess defined by a respective one of the first and second curved surfaces. The annular recess is coaxial with the frustoconical receiver. In the assembled configuration, the annular recess receives the annular projection.

In one implementation, the frustoconical protrusion includes a first frustoconical protrusion and a second frustoconical protrusion. The frustoconical receiving portion includes a first frustoconical receiving portion and a second frustoconical receiving portion. The annular protrusion includes a first annular protrusion and a second annular protrusion. The annular recess includes a first annular recess and a second annular recess.

In one implementation, the gearbox further includes an elastomeric layer. The resilient layer is disposed on at least one of the first curved surface or the second curved surface.

In one implementation, one of the first and second portions includes an integral rivet. An integral rivet extends from a respective one of the first and second curved surfaces. The other of the first and second portions includes an aperture defined in a respective one of the first and second curved surfaces that is configured to receive a portion of the integral rivet.

In one implementation, the gearbox further includes a plurality of fasteners. The plurality of fasteners are configured to couple the first portion and the second portion to one another.

In one implementation, the gearbox is configured to house at least a portion of the spindle screw and the cross-axis gear system. The cross-axis gear system includes a first gear operatively coupled with a second gear. The second gear is operatively coupled with the spindle screw.

In one implementation, the gearbox is a universal gearbox. The gear system is configured to operate in one of: (i) a relaxation speed having a linear regulation speed in a range from 17mm/s to 22mm/s, (ii) a high speed having a linear regulation speed in a range from 50mm/s to 55mm/s, or (iii) an ultra-high speed having a linear regulation speed in a range from 80mm/s to 85 mm/s.

In one implementation, the first gear is a cylindrical worm gear and the second gear is one of a helical gear or a single wrap worm gear.

A vehicle seat adjustment assembly in accordance with the principles of the present invention is provided. The vehicle seat adjustment assembly includes a gear box, a gear system, and a spindle screw. The gearbox assembly includes a first portion and a second portion. The first portion includes a first body. The first body defines a first longitudinal recess and a first peripheral recess in fluid communication with the first longitudinal recess. The first body includes a first curved surface. The first curved surface is concave. The second portion includes a second body. The second body defines a second longitudinal recess and a second peripheral recess. The second body includes a second curved surface. The second longitudinal recess cooperates with the first longitudinal recess to define a longitudinal passageway. The second peripheral recess cooperates with the first peripheral recess to define a peripheral receptacle. The second curved surface is convex, has an equal and opposite curvature compared to the first curved surface, and is in contact with the first curved surface. The gear system includes a first gear and a second gear. The first gear is at least partially disposed within the peripheral receptacle. The first gear includes a first external thread. The first gear is configured to rotate about a first axis. The second gear is at least partially disposed within the longitudinal passageway. The second gear includes external teeth and internal threads. The second gear defines a gear path. The external teeth are operatively coupled with the first external threads. The second gear is configured to rotate about a second axis perpendicular to the first axis. The spindle screw passes through the gear passage. The spindle screw includes a second external thread. The second external thread is operatively coupled with the internal thread.

In one implementation, the second gear is one of (i) a helical gear or (ii) a single wrap worm gear.

In one implementation, the second external thread is a trapezoidal thread, and the spindle screw has a lead of 3mm, a pitch of 1.5mm, and one of (i) a nominal diameter of 8mm and (ii) a nominal diameter of 9 mm.

In one implementation, the gear system is configured to operate in one of: (i) a relaxation speed having a linear regulation speed in a range from 17mm/s to 22mm/s, (ii) a high speed having a linear regulation speed in a range from 50mm/s to 55mm/s, or (iii) an ultra-high speed having a linear regulation speed in a range from 80mm/s to 85 mm/s.

In one implementation, one of the first and second portions includes a frustoconical protrusion and an annular protrusion extending from a respective one of the first and second curved surfaces. The annular projection is disposed around the base of the frustoconical projection and is coaxial with the frustoconical projection. The other of the first and second portions includes a frustoconical receptacle and an annular recess defined by a respective one of the first and second curved surfaces. The annular recess is coaxial with the frustoconical receiver. The frustoconical receiving portion is configured to receive the frustoconical protrusion and the annular recess is configured to receive the annular protrusion.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

Drawings

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is a partial perspective view of a vehicle seat assembly having a pair of seat track assemblies, each including a powered seat length adjustment assembly according to the principles of the present invention;

FIG. 2 is a perspective view of the powered seat length adjustment assembly of FIG. 1;

FIG. 3 is an exploded perspective view of an adjustment subassembly of the powered seat length adjustment assembly of FIG. 2;

FIGS. 4A-4E relate to a closed gearbox having ellipsoidal mating surfaces in accordance with the principles of the present invention; FIG. 4A is a perspective view of a gear box and a representative ellipsoid; FIG. 4B is a perspective view of the gearbox; FIG. 4C is a first side view of the gearbox; FIG. 4D is a second side view of the gearbox; and FIG. 4E is an exploded perspective view of the gearbox;

FIGS. 5A-5B relate to an open gear box having ellipsoidal mating surfaces according to the principles of the present invention; FIG. 5A is a perspective view of a gearbox; and FIG. 5B is an exploded perspective view of the gearbox;

FIGS. 6A-6D relate to an open style gearbox having conical mating surfaces in accordance with the principles of the present invention; FIG. 6A is a perspective view and representative conical surface of a gearbox; FIG. 6B is a first side view of the gearbox; FIG. 6C is a second side view of the gearbox; and FIG. 6D is an exploded perspective view of the gearbox;

FIGS. 7A-7E relate to an open type gearbox having spherical mating surfaces according to the principles of the present invention; FIG. 7A is a perspective view of a gear box and a representative spherical surface; FIG. 7B is a perspective view of the gearbox; FIG. 7C is a first side view of the gearbox; FIG. 7D is a second side view of the gearbox; FIG. 7E is an exploded perspective view of the gearbox;

fig. 8A-8B relate to pre-assembled binding stop features; FIG. 8A is a detailed perspective view of the recessed portion of the pre-assembled binding stop feature of the gearbox of FIG. 5B; and fig. 8B is a detailed perspective view of the boss of the pre-assembled binding stop feature of fig. 5B;

FIG. 9 is an exploded perspective view of a gearbox including a single integral stop feature according to the principles of the present invention;

FIG. 10 is an exploded perspective view of a gearbox without a pre-assembled binding stop feature according to the principles of the present invention;

11A-11B relate to a gearbox including an elastomeric layer according to the principles of the present invention; FIG. 11A is an exploded perspective view of the gearbox; FIG. 11B is a perspective view of the gear box;

12A-12C relate to a gearbox assembly including the gearbox of FIGS. 5A-5B assembled with screws in accordance with the principles of the present invention; FIG. 12A is a perspective view of the gear box assembly; and FIG. 12B is a partial cross-sectional view taken at line 12B-12B of FIG. 12A; FIG. 12C is a cross-sectional view taken at line 12C-12C of FIG. 12A;

13A-13D relate to a gearbox assembly including the gearbox of FIGS. 5A-5B assembled with breakaway rivets in accordance with the principles of the present disclosure; FIG. 13A is an exploded perspective view of the gear box assembly with the rivets in an undeformed state; FIG. 13B is a perspective view of the gearbox assembly with the rivets in an undeformed state; FIG. 13C is a cross-sectional view of the gearbox assembly taken along line 13C-13C of FIG. 13B, with the rivets in an undeformed state; FIG. 13D is a cross-sectional view of the gearbox assembly taken at line 13D-13D of FIG. 13B, with the rivet in a deformed state;

14A-14D relate to a gearbox assembly including a gearbox with integral rivets according to the principles of the present disclosure; FIG. 14A is an exploded perspective view of the gearbox with the rivets in an undeformed state; FIG. 14B is a perspective view of the gearbox with the rivets in an undeformed state; FIG. 14C is a cross-sectional view taken at line 14C-14C of FIG. 14B, with the rivet in an undeformed state; and FIG. 14D is a cross-sectional view taken at line 14D-14D of FIG. 14B, the rivet being in a deformed state;

FIGS. 15A-15D relate to an enhanced strength, geared, slow speed motorized length adjustment assembly according to the principles of the present invention; FIG. 15A is a partial perspective view of the adjustment assembly; FIG. 15B is a partial perspective cutaway view of the adjustment assembly; FIG. 15C is a cross-sectional view of the adjustment assembly taken at line 15C-15C of FIG. 15A; and FIG. 15D is a cross-sectional view of the adjustment assembly taken at line 15D-15D of FIG. 15A;

FIGS. 16A-16E relate to an enhanced strength, helical geared, slow speed motorized length adjustment assembly according to the principles of the present invention; FIG. 16A is a partially exploded perspective view of the adjustment assembly;

FIG. 16B is a partial perspective view of the adjustment assembly; FIG. 16C is a partial perspective cutaway view of the adjustment assembly;

FIG. 16D is a cross-sectional view of the adjustment assembly taken at line 16D-16D of FIG. 16B; and FIG. 16E is a cross-sectional view of the adjustment assembly taken at line 16E-16E of FIG. 16B;

FIGS. 17A-17D relate to a normal strength, gear-enveloping, high speed, electrically powered length adjustment assembly according to the principles of the present invention; FIG. 17A is a partial perspective view of the adjustment assembly; FIG. 17B is a partial perspective cutaway view of the adjustment assembly; FIG. 17C is a cross-sectional view of the adjustment assembly taken at line 17C-17C of FIG. 17A; and FIG. 17D is a cross-sectional view of the adjustment assembly taken at line 17D-17D of FIG. 17A;

18A-18D relate to a normal strength, helical geared, high speed motorized length adjustment assembly according to the principles of the present invention; FIG. 18A is a partial perspective view of the adjustment assembly; FIG. 18B is a partial perspective cutaway view of the adjustment assembly; FIG. 18C is a cross-sectional view taken at line 18C-18C of FIG. 18A; and FIG. 18D is a cross-sectional view taken at line 18D-18D of FIG. 18A; and

FIGS. 19A-19D relate to normal strength, helical gear, ultra high speed motorized length adjustment according to the principles of the present invention; FIG. 19A is a partial perspective view of the adjustment assembly; FIG. 19B is a partial perspective cutaway view of the adjustment assembly; FIG. 19C is a cross-sectional view taken at line 19C-19C of FIG. 19A; and FIG. 19D is a cross-sectional view taken at line 19D-19D of FIG. 19A.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings.

Example embodiments are provided so that this disclosure will be thorough and will fully convey the scope to those skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods to provide a thorough understanding of embodiments of the present invention. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms, and that neither should be construed to limit the scope of the invention. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Unless specifically indicated as an order of execution, the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated. It should also be understood that additional or alternative steps may be employed.

When an element or layer is referred to as being "on," "engaged to," "connected to" or "coupled to" another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly engaged to," "directly connected to" or "directly coupled to" another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements (e.g., "between … …," "with" directly between … …, "" adjacent "directly adjacent," etc.) should be construed in a similar manner. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

Spatially relative terms, such as "inner," "outer," "below," "lower," "over," "above," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Referring to fig. 1, a seat assembly 10 is provided. The seat assembly 10 may include a seat back 12, a seat bottom 14, and one or more seat track assemblies 16. In some embodiments, the seat assembly 10 is adjustably mounted to a vehicle (not shown), such as an automobile. For example, a recliner mechanism (not shown) may pivotally move the seat back 12 relative to the seat bottom 14 and the seat track assembly 16 may translatably move the seat bottom 14 to a particular position relative to a vehicle chassis (not shown). Thus, a user may selectively change the orientation of the seat back 12 relative to the seat bottom 14 using a recliner mechanism (not shown) and change the position of the seat assembly 10 relative to the vehicle chassis using a pair of seat track assemblies 16.

Each seat track assembly 16 may include a lower track 20, an upper track 22, and an adjustment assembly 24. The adjustment assembly 24 may be fixedly attached to a portion of the upper track 22 by one or more mechanical fasteners 26 (e.g., bolts, screws, rivets, etc.). In certain implementations, the upper track 22 defines one or more cutouts (not shown) to accommodate the adjustment assembly 24.

The lower track 20 may be fixedly attached to a portion of the vehicle using one or more mechanical fasteners 28 (e.g., bolts, screws, rivets, etc.) or any other suitable fastening technique, and the lower track 20 may define an axis a 1. The lower track 20 may define a profile of a U-shape extending in a direction generally parallel to the axis a1 such that the walls of the lower track 20 cooperate to define the central lower channel 30.

The upper track 22 may be fixedly attached to a portion of the seat bottom 14 using one or more mechanical fasteners 32 (e.g., bolts, screws, rivets, etc.) or any other suitable fastening technique. The upper track 22 may define a profile of a U-shape extending in a direction generally parallel to the axis a1 such that the walls of the upper track 22 cooperate to define the central upper channel 34.

In the assembled configuration as shown, the lower track 20 may support the upper track 22 to translate the upper track 22 along axis a1 such that the upper track 22 translates relative to the vehicle. For example, lower track 20 may slidably support upper track 22 to translate upper track 22 along axis a 1. The upper track 22 may translate relative to the lower track 20 to allow the seat back 12 and the seat bottom 14 to selectively move relative to the vehicle. Movement of the upper track 22 relative to the lower track 20 may be facilitated by a carriage assembly 50 including two pairs of ball cage assemblies 52, the ball cage assemblies 52 being: (i) is fixed to the upper track 22 and/or the adjustment assembly 24, and (ii) is at least partially received within the central lower channel 30 of the lower track 20.

Referring to FIG. 2, the adjustment assembly 24 may include a driver assembly 54, a spindle screw or lead screw 56, and an adjustment subassembly 58. In the assembled configuration, a portion of the adjustment assembly 24 may be fixed relative to the vehicle and another portion of the adjustment assembly 24 may be fixed relative to the upper track 22 to facilitate movement of the seat back 12 and seat bottom 14 relative to the vehicle. For example, spindle screw 56 may be secured to lower track 20 and/or to the vehicle floor, while adjustment subassembly 58 may be secured to upper track 22. Thus, movement of the adjustment subassembly 58 relative to the spindle screw 56 causes fore and aft movement of the upper track 22 and seat bottom 14 relative to the lower track 20 and ultimately relative to the vehicle floor.

The driver assembly 54 may include a bi-directional electric motor and two flexible drive shafts that transfer speed and torque from the electric motor to the adjustment subassembly 58 to cause movement of the adjustment subassembly 58 along the length of the spindle screw 56 and, thus, fore and aft movement of the seat assembly 10 (fig. 1) relative to the vehicle floor.

The spindle screw 56 may include a front end 62 and a rear end 64. In some implementations, the spindle screw 56 may define a generally cylindrical rod defining an axis a2 extending from the forward end 62 to the rearward end 64 and having external threads 66 extending from the forward end 62 to the rearward end 64 along an axis a2 and about an axis a 2. In the assembled configuration, the spindle screw 56 may be disposed within one or both of the central lower channel 30 of the lower track 20 and the central upper channel 34 of the upper track 22 such that the axis a2 is substantially parallel to the axis a1 (fig. 1). The front and rear ends 62, 64 may be fixed relative to the lower track 20 and/or relative to the vehicle floor by studs rigidly mounted to the lower track 20. For example, the front end 62 may be supported by a front spindle bracket 68, the front spindle bracket 68 being fixed to the lower track 20 and/or to the vehicle floor, and the rear end 64 may be supported by a rear spindle bracket 70, the rear spindle bracket 70 also being fixed to the lower track 20 and/or to the vehicle floor.

Referring at least to fig. 3, the adjustment subassembly 58 may include: a support frame 74; a housing assembly 76; a pair of support bushings 78; a first toothed or cylindrical worm 80, the first toothed or cylindrical worm 80 having a helical external thread 82 meshing with an external toothing 84 of a second toothed or enveloping worm 86; a spindle nut integrally formed with the second gear 86 and having internal threads 90, and the spindle screw 56 of the external threads 66 (fig. 2) engaging the internal threads 90 of the spindle nut. The first gear 80 and the second gear 86 may be collectively referred to as a gear system or gear assembly.

The support frame 74 may define a U-shape. The support frame 74 may include a base 100, a pair of walls 102 extending generally perpendicular to the base 100 on opposite ends of the base 100, and a pair of flanges 104 extending generally perpendicular to the pair of walls 102 and generally parallel to the base 100, respectively. The base 100, wall 102, and flange 104 may be integrally formed. The base 100 and the wall 102 may cooperate to define an interior region 106. The pair of walls 102 may define a corresponding pair of wall openings 108. The pair of flanges 104 may define a corresponding pair of flange apertures 110.

Housing assembly 76 may include a gear box 114, a first casing 116, and a second casing 118 (also referred to as a "pair of

casings

116, 118"). The first enclosure 116 and the second enclosure 118 may be geometrically mirror images. The first and

second shells

116, 118 may define respective first and

second shell apertures

120, 122. The first and

second casing shells

116, 118 may define first and second shell

interior regions

124, 126, respectively.

The first and

second housings

116, 118 may be formed of an elastic material having noise and vibration damping characteristics. In some implementations, for example, the first and

second housings

116, 118 can be formed from a polymer, such as rubber. The use of

rubber boots

116, 118 that compress against the wall 102 of the support frame 74 may improve the damping capacity of the adjustment subassembly 58 during vibration transmission to the seat structure.

The gearbox 114 may be formed from an aluminum zinc alloy diecast material. The gearbox 114 may include a first component or portion 130 and a second component or portion 132. Each of the first and

second portions

130, 132 may define a longitudinal recess 134, a peripheral recess 136, and an aperture 138. Each of the first and

second portions

130, 132 also includes a curved mating surface 140. In the assembled state, the curved mating surfaces 140 of the first and

second portions

130, 132 contact each other, the longitudinal recesses 134 cooperate to define a longitudinal passage, and the peripheral recesses 136 cooperate to define a peripheral receptacle. The gearbox 114 may be secured in the assembled configuration by a plurality of fasteners 142 (e.g., screws, bolts, rivets, etc.). Various implementations of the gearbox are described in more detail below.

The barrel worm 80 may define an axis of rotation a3 extending from the first end 150 to the second end 152. The helical external thread 82 may be disposed about the rotational axis a3 between the first end 150 and the second end 152. In various implementations, the barrel worm 80 may be manufactured from a plastic material such as PEEK 450G by an injection molding process. The barrel worm 80 may be rotatably supported by the housing assembly 76. For example, the first end 150 of the barrel worm 80 may be rotatably disposed within the bore 138 of the first portion 130 of the gear box 114, and the second end 152 of the barrel worm 80 may be rotatably disposed within the bore 138 of the second portion 132 of the gear box 114.

The envelope worm 86 may define an axis of rotation a4 extending from the first end 154 to the second end 156. The internal threads 90 and the external teeth 84 may be disposed about an axis of rotation a 4. The bearing bushing 78 may include a corresponding through hole 160, the through hole 160 receiving an outer bearing surface 162 of the enveloping worm 86. In the assembled configuration, the enveloping worm 86 and the bearing bushing 78 may be at least partially disposed within the longitudinal passageway (formed by the longitudinal recess 134) of the gear box 114. The enveloping worm 86 may be disposed between the support bushings 78 and may be rotatable relative to the support bushings 78. The support bushing 78 may be rotatably fixed relative to the gearbox 114 by engagement of the radially extending boss 164 of the support bushing 78 with the gearbox 114.

In the assembled configuration, the gearbox 114 is disposed between the

casing shells

116, 118, and the gearbox 114 is at least partially located within the shell

interior regions

124, 126. The housing assembly 76, including the gearbox 114 and the

enclosures

116, 118, is at least partially disposed within the interior region 106 of the support frame 74. Spindle screw 56 (fig. 2) extends through gear passage 166 of enveloping worm 86, through-hole 160 of bearing bushing 78, longitudinal passage (formed by longitudinal recess 134), first and

second housing apertures

120, 122, and wall aperture 108. The internal threads 90 of the enveloping worm 86 are threaded onto the external threads 66 (fig. 2) of the spindle screw 56 (fig. 2), and the external teeth 84 of the enveloping worm 86 mesh with the helical external threads 82 of the barrel worm 80.

The axis of rotation a4 of the envelope worm 86 may be substantially parallel to the axis a2 of the spindle screw 56 and aligned with the axis a2 of the spindle screw 56. The axis of rotation A3 of the barrel worm 80 may be substantially perpendicular to the axes a2 and a 4. In the assembled configuration, the adjustment subassembly 58 may be disposed within the central lower channel 30 of the lower track 20 and/or the central upper channel 34 of the upper track 22. The axes a2, a4 may be substantially parallel to the axis a1 and aligned with the axis a 1.

Gear box

As will be described in greater detail below, a gearbox according to the principles of the present invention may have one or more features to facilitate alignment of two parts of the gearbox, distribute stresses, increase ease of assembly, improve accuracy of assembly, accommodate manufacturing tolerances, reduce or eliminate vibration and/or noise during use, and/or provide modularity to accommodate the configuration of various gear assemblies. More specifically, a gearbox according to principles of the present disclosure may include a curved mating surface, one or more pre-assembly bond stop features, and/or an elastic layer, each of which is described in more detail below.

Further, any gearbox may be an open gearbox or a closed gearbox. The enclosed gear box includes a wall, such as a top wall, that at least partially encloses the worm gear. Enclosed gearboxes may be used to reduce or eliminate contamination of the gear system inside the gearbox and/or to eliminate noise during use of the gear system. In some implementations, an enclosed gearbox may be used to facilitate reduction of noise in a very high speed gear system that operates at a higher mesh frequency than a low speed gear system. An example of a closed type gearbox is shown in fig. 4A to 4E. Open gearboxes may be used in applications with low or no expected contamination and/or low expected noise. In some implementations, the open gearbox may be used with a slow speed or high speed gear system that is not expected to emit significant noise during use. Examples of the open type gear box are shown in fig. 5A to 7E, 9 to 11B, and 15A to 19D.

The first and second parts of the gearbox can be manufactured in a die-casting process. The gearbox may comprise a cast metal, such as an aluminium zinc alloy. The gearbox may be assembled using various types of separate or integral fasteners.

Curved mating surfaces

A two-part gearbox according to the principles of the present invention may include curved mating surfaces. The curved mating surface may be defined by a portion of a three-dimensional curved profile such as an ellipsoid, a cone or a sphere. The two-part gearbox may include a first part having a first curved mating surface and a second part having a second curved mating surface. One of the mating surfaces is convex and the other mating surface is concave. The mating surfaces may define substantially the same shape with the same and opposite curvature.

The mating surface may be self-centering in at least two orthogonal directions. In certain implementations, the mating surface is self-centering in three orthogonal directions (e.g., spherical mating surfaces). Thus, the curved mating surfaces may facilitate efficient assembly and pre-assembly with improved precision. Further, a gearbox with a self-centering mating surface may lack certain other alignment features. In addition to facilitating alignment, the curved mating surfaces also increase surface area contact between the two gearbox portions, thereby improving the distribution of shear stresses in the gearbox assembly during normal and/or impact load conditions.

Referring to fig. 4A-4E, a gearbox 400 in accordance with the principles of the present invention is provided. The gearbox 400 includes a first component or portion 402 and a second component or portion 404. A boundary or junction 406 between the first portion 402 and the second portion 404 defines a portion of an ellipsoid 408. The ellipsoid 408 may define a first or vertical radius and a second or horizontal radius. In certain implementations, the first radius is in a range of 190mm to 200mm and the second radius is in a range of 240mm to 250 mm.

The first portion 402 includes a first body 410. The first body 410 includes a first exterior surface 412 and a first mating or curved surface 414. The first mating surface 414 is concave such that the first mating surface 414 curves 415 inward away from the second portion 404. The second portion 404 includes a second body 416. The second body 416 includes a second exterior surface 418 and a second mating or curved surface 420. The second mating surface 420 is convex such that the second mating surface 420 curves outward 421 toward the first portion 402. The curvatures of the first mating surface 414 and the second mating surface 420 are approximately equal and opposite. More specifically, the first mating surface 414 is defined by a portion of a radially outer portion 422 of the ellipsoid 408 and the second mating surface 420 is defined by a portion of a radially inner portion 424 of the ellipsoid 408.

During pre-assembly of the gearbox 400, the mating surfaces 414, 420 may be configured to have a self-centering effect on the first and

second portions

402, 404 to facilitate alignment of the first and

second portions

402, 404. The mating surfaces 414, 420 may not be in full contact (i.e., there may be a gap between the first mating surface 414 and the second mating surface 420) prior to alignment during pre-assembly. One or both of the

portions

402, 404 may be moved relative to the other of the

portions

402, 404 along a first orthogonal direction 426 and/or a second orthogonal direction 428 until the

portions

402, 404 slide into alignment. This may be referred to as bi-directional self-centering. When the

portions

402, 404 are aligned, the first mating surface 414 and the second mating surface 420 may be in substantially continuous contact at the boundary 406.

The first body 410 of the first portion 402 defines a first longitudinal recess 440 and a first peripheral recess 442. The first longitudinal recess 440 and the first peripheral recess 442 are in fluid communication. The first body 410 includes a first wall 444. The first wall 444 at least partially defines a first peripheral recess 442. The first wall 444 may be partially cylindrical.

The second body 416 of the second portion 404 defines a second longitudinal recess 446 and a second peripheral recess 448. The second longitudinal recess 446 and the second peripheral recess 448 are in fluid communication. The second body 416 includes a second wall 450. The second wall 450 at least partially defines a second peripheral recess 448. The second wall 450 may be partially cylindrical.

The first and second

longitudinal recesses

440, 446 cooperate to define a longitudinal passage 452 (fig. 4B-4C). The longitudinal passage 452 may extend continuously between the first and second sides of the gearbox 400. When the gear box 400 is assembled in the vehicle seat adjustment assembly, the longitudinal passage 452 may be aligned with an axis of the lower track, the spindle screw, and the second gear (e.g., the lower track 20, the spindle screw 56, and the second gear 86 of fig. 1-3). The longitudinal passage 452 may be configured to receive the second gear, a portion of the spindle screw, and a bearing (e.g., the second gear 86, the spindle screw 56, and the bearing bushing 78 of fig. 1-3).

The first and second

peripheral recesses

442, 448 cooperate to define a peripheral receptacle 454 (fig. 4C). The peripheral receptacle 454 is partially enclosed by the first and

second walls

444, 450. Accordingly, gearbox 400 may be described as an enclosed gearbox. The peripheral receptacle 454 may be configured to receive a first gear (e.g., the first gear 80 of fig. 1-3). The first body 410 and the second body 416 may define respective first and

second apertures

460, 462. The first and

second apertures

460, 462 may be configured to support first and second bearing surfaces of a first gear (e.g., the first gear 80 of fig. 1-3).

The first body 410 of the first portion 402 may define a plurality of third apertures 464. The second body 416 of the second portion 404 may define a plurality of fourth apertures 466. When the gearbox 400 is assembled, the third apertures 464 are axially aligned with the fourth apertures 466, respectively. The

apertures

444, 466 may be configured to receive a plurality of fasteners as will be described in more detail below (see discussion accompanying fig. 12A-14D) to retain the gearbox 400 in an assembled configuration.

The gearbox 400 may also include a pair of pins 470 and a pair of receivers 472. In the implementation shown, the pin 470 protrudes from the second mating surface 420 of the second portion 404, and a receptacle 472 is defined in the first body 410 of the first portion 402. However, in other implementations, the first portion may include a pin and the second portion may include a receptacle. In some implementations, the first portion and the second portion may each include one pin and one receiver.

The receiving portion 472 may be a blind hole. The pin 470 may be frustoconical such that the pin 470 has a maximum diameter adjacent the second body 416. The receiver 472 may be frustoconical such that the receiver 472 has a maximum diameter at the first mating surface 414. The receivers 472 may be configured to receive the respective pins 470 during pre-assembly of the gearbox 400. When the gearbox 400 is in an assembled configuration, the pin 470 may be disposed in the receptacle 472.

In various implementations, the gearbox 400 may also include one or more pre-assembled bond stop features. For example, the gearbox 400 may include an annular protrusion 480 to be received in an annular recess 482. The annular protrusion 480 may be coaxial with the pin 470 and the annular recess 482 may be coaxial with the receiver 472. A gearbox according to principles of the present invention may be devoid of pre-assembly incorporating stop features that include a single stop feature, two stop features as shown (e.g., a pair of annular protrusions 480 and a pair of annular recesses 482), or more than two stop features. The pre-assembly bond stop feature is described in more detail below in the discussion accompanying fig. 8A-10.

Referring to fig. 5A-5B, another gearbox 400a is illustrated. The structure and function of gearbox 400a may be substantially similar to that of gearbox 400, with any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain an alphabetic extension (i.e., "a") to identify those features that have been modified.

The gearbox 400a includes a first component or portion 402a and a second component or portion 404 a. A boundary or junction 406a between the first portion 402a and the second portion 404a defines a portion of an ellipsoid 408.

The first portion 402a includes a first body 410 a. The first body 410a includes a first exterior surface 412a and a first mating surface or first curved surface 414 a. The first mating surface 414a is concave. The second portion 404a includes a second body 416 a. The second body 416a includes a second exterior surface 418a and a second mating or curved surface 420 a. The second mating surface 420a is convex.

The first body 410a of the first portion 402a defines a first longitudinal recess 440 and a first peripheral recess 442 a. The first longitudinal recess 440 and the first peripheral recess 442a are in fluid communication. The second body 416a of the second portion 404a defines a second longitudinal recess 446 and a second peripheral recess 448 a. The second longitudinal recess 446 and the second peripheral recess 448a are in fluid communication.

The first and second

longitudinal recesses

440, 446 cooperate to define a longitudinal passage 452 (fig. 5A). The first and second

peripheral recesses

442a, 448a cooperate to define a peripheral receptacle 454a (fig. 5A). When the gearbox 400a is in the assembled configuration, the peripheral receptacle 454a opens to an outer region 500 of the gearbox 400a at a peripheral opening 502 defined by the first and

second bodies

410a, 416 a. Accordingly, gearbox 400a may be described as an open gearbox. The outer peripheral receptacle 454a can be configured to at least partially receive a first gear (e.g., the first gear 80 of fig. 1-3), such as in first and

second apertures

460, 462 that support first and second bearing surfaces of the first gear. A portion of the first gear may protrude from the gear case 400a through the outer circumferential opening 502.

The gearbox 400a may also include third and

fourth apertures

464, 466 for receiving fasteners, pins 470 and receivers 472, and annular protrusions 480 and recesses 482 as shown and described above in the discussion of fig. 4A-4E.

Referring to fig. 6A-6D, another gearbox 400b is illustrated. The structure and function of gearbox 400b may be substantially similar to that of gearbox 400a, with any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain an alphabetic extension (i.e., "b") to identify those features that have been modified.

The gearbox 400b includes a first component or portion 402b and a second component or portion 404 b. A boundary or junction 406b between the first portion 402b and the second portion 404b defines a portion of the cone 600. In certain implementations, the cone 600 may define an opening angle in the range of 165 ° to 172 °.

The first portion 402b includes a first body 410 b. The first body 410b includes a first exterior surface 412a and a first mating surface or first curved surface 414 b. The first mating surface 414b is concave such that the first mating surface 414b curves 415 inward away from the second portion 404 b. The second portion 404b includes a second body 416 b. The second body 416b includes a second exterior surface 418a and a second mating surface or second curved surface 420 b. The second mating surface 420b is convex such that the second mating surface 420b curves outward 421 toward the first portion 402 b. The curvatures of the first mating surface 414b and the second mating surface 420b are substantially equal and opposite.

During pre-assembly of the gearbox, the mating surfaces 414b, 420b may be configured to have a self-centering effect on the first and

second portions

402b, 404b to facilitate alignment of the first and

second portions

402b, 404 b. The mating surfaces 414b, 420b may not be in full contact (i.e., there may be a gap between the first mating surface 414b and the second mating surface 420 b) prior to alignment during pre-assembly. One or both of the

portions

402b, 404b may be moved relative to the other of the

portions

402b, 404b along the first orthogonal direction 426 and/or the second orthogonal direction 430 until the

portions

402b, 404b slide into alignment. This may be referred to as bi-directional self-centering. When the

portions

402b, 404b are aligned, the first mating surface 414b and the second mating surface 420b may be in substantially continuous contact at the boundary 406 b.

The first body 410b of the first portion 402b defines a first longitudinal recess 440 and a first peripheral recess 442 a. The first longitudinal recess 440 and the first peripheral recess 442a are in fluid communication. The second body 416b of the second portion 404b defines a second longitudinal recess 446 and a second peripheral recess 448 a. The second longitudinal recess 446 and the second peripheral recess 448a are in fluid communication. The first and second

longitudinal recesses

440, 446 cooperate to define a longitudinal passage 452 (fig. 6A-6B). The first and second

peripheral recesses

442a, 448a cooperate to define a peripheral receptacle 454a (fig. 6A). Although the gearbox 400a is shown as an open gearbox, in other implementations, the gearbox 400a may include walls similar to or the same as the walls 444, 450 (fig. 4A-4E) of the gearbox 400, and the gearbox 400a is a closed gearbox.

The gearbox 400b may also include third and

fourth apertures

464, 466 for receiving fasteners, pins 470 and receivers 472, and annular protrusions 480 and annular recesses 482 as shown and described above in the discussion accompanying fig. 4A-4E.

Referring to fig. 7A-7E, another gearbox 400c is illustrated. The structure and function of gearbox 400c may be substantially similar to that of gearbox 400a, with any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain an alphabetic extension (i.e., "c") to identify those features that have been modified.

The gearbox 400c includes a first component or portion 402c and a second component or portion 404 c. A boundary or junction 406c between the first portion 402c and the second portion 404c defines a portion of the sphere 700. In certain implementations, sphere 700 may define a radius in the range of 190mm to 200 mm.

The first portion 402c includes a first body 410 c. The first body 410c includes a first exterior surface 412a and a first mating surface or first curved surface 414 c. The first mating surface 414c is concave such that the first mating surface 414c curves 415 inward away from the second portion 404 c. The second portion 404c includes a second body 416 c. The second body 416c includes a second exterior surface 418a and a second mating surface or second curved surface 420 c. The second mating surface 420c is convex such that the second mating surface 420c curves outward 421 toward the first portion 402 c. The curvatures of the first mating surface 414c and the second mating surface 420c are substantially equal and opposite.

During pre-assembly of the gearbox, the mating surfaces 414c, 420c may be configured to have a self-centering effect on the first and

second portions

402c, 404c to facilitate alignment of the first and

second portions

402c, 404 c. The mating surfaces 414c, 420c may not be in full contact (i.e., there may be a gap between the first mating surface 414c and the second mating surface 420 c) prior to alignment during pre-assembly. One or both of the

portions

402c, 404c may be moved relative to the other of the

portions

402c, 404c along the first orthogonal direction 426, the second orthogonal direction 430, and/or the third orthogonal direction 702 until the

portions

402c, 404c slide into alignment. This may be referred to as three-way self-centering. When the

portions

402c, 404c are aligned, the first mating surface 414c and the second mating surface 420c may be in substantially continuous contact at the boundary 406 c.

The first body 410c of the first portion 402c defines a first longitudinal recess 440 and a first peripheral recess 442 a. The first longitudinal recess 440 and the first peripheral recess 442a are in fluid communication. The second body 416c of the second portion 404c defines a second longitudinal recess 446 and a second peripheral recess 448 a. The second longitudinal recess 446 and the second peripheral recess 448a are in fluid communication. The first and second

longitudinal recesses

440, 446 cooperate to define a longitudinal passage 452 (fig. 7B-7C). The first and second

peripheral recesses

442a, 448a cooperate to define a peripheral receptacle 454a (fig. 7B). Although the gearbox 400c is shown as an open gearbox, in other implementations, the gearbox 400c may include walls similar to or the same as the walls 444, 446 (fig. 4A-4E) of the gearbox 400, and the gearbox 400c is a closed gearbox.

The gearbox 400c may also include third and

fourth apertures

Pre-assembled binding stop feature

A gearbox according to the principles of the present invention may include one or more features to facilitate pre-assembly and provide flexibility to accommodate manufacturing tolerances. The gearbox may include a single pre-assembled binding stop feature, dual pre-assembled binding stop features, or more than two pre-assembled binding stop features. In various implementations, the gearbox may be devoid of pre-assembled binding stop features.

Referring to FIG. 8A, a portion of the second body 416a of the gearbox 400a of FIG. 5A is shown. This portion includes a pin 470 and an annular projection 480. In various implementations, the pin 470 and the annular protrusion 480 may be integrally formed with the second body 420 a.

The pin 470 protrudes from the second mating surface 420 a. The pin 470 may have a frustoconical shape such that the pin 470 has a larger diameter at a proximal end or base closer to the second mating surface 420a and a smaller diameter at a distal end 800 distal from the second mating surface 420 a. The pin 470 includes a frustoconical first bonding surface 802.

The annular protrusion 480 may have a larger radius than the pin 470, and the annular protrusion 480 extends circumferentially around the base of the pin 470. An annular protrusion may extend axially from the second mating surface 420a toward the distal end 800 of the pin 470. However, the annular protrusion 480 may extend axially along only a portion of the length of the pin 470. The annular protrusion 480 includes a second engagement surface 804.

Referring to fig. 8B, the first body 410a includes a receiving portion 472 and an annular recess 482. The receiver 472 may be defined by the first mating surface 414 a. The receiver 472 may have a frustoconical shape such that the receiver 472 has a larger diameter at the proximal end 806 at the first mating surface 414a and a smaller diameter at the distal end 808 offset from the first mating surface 414 a. The receiving portion 472 includes a third coupling surface 810 having a truncated cone shape.

The annular recess 482 may have a larger radius than the receiver 472, and the annular recess 482 extends circumferentially around a portion of the receiver. The annular recess may extend axially from the first mating surface 414a to the distal end 808 of the receiver 472. However, the annular recess 482 may extend axially along only a portion of the length of the receiver 472. The annular recess 482 may include a fourth bonding surface 812.

When the gearbox 400a (fig. 5A) is in an assembled or pre-assembled configuration, the pin 470 is received in the receiver 472. The first coupling surface 802 of the pin 470 may engage with the third coupling surface 810 of the receiver 472. The annular protrusion 480 is received in the annular recess 482. The second coupling surface 814 of the annular protrusion 480 may engage the fourth coupling surface 812 of the annular recess 482. The annular protrusion 480 and annular recess 482 may be collectively referred to as a pre-assembly bond stop feature.

Returning to fig. 5A, the gearbox 400a may include two pre-assembled bond stop features, such as two pairs of annular protrusions 480 and annular recesses 482. That is, the gearbox 400a may have dual bond stop features. As shown, the first portion 402a may include a receiver 472 and an annular recess 482, and the second portion 404a may include a pin 470 and an annular protrusion 480. In various other implementations, the first portion may include a pin and a protrusion, while the second portion includes a receiver and a recess. In various other implementations, both the first portion and the second portion may include a pin, an annular protrusion, a receptacle, and an annular recess.

Referring to FIG. 9, another gearbox 400d is illustrated. The structure and function of gearbox 400d may be substantially similar to that of gearbox 400a, with any exceptions described below and/or shown otherwise in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain the letter extension (i.e., "d") to identify those features that have been modified.

The gearbox 400d includes a first component 402d or first portion 402d and a second component 404d or second portion 404 d. A boundary or junction between the first portion 402d and the second portion 404d (see, e.g., boundary 406a of fig. 5A) defines a three-dimensional curved profile, such as a portion of one of an ellipsoid, a cone, or a sphere.

The first portion 402d includes a first body 410 d. The first body 410d includes a first exterior surface 412a and a first mating surface 414d or first curved surface 414 d. The second portion 404d includes a second body 416 d. The second body 416d includes a second exterior surface 418a and a second mating or curved surface 420 d. One of the first mating surface 414d and the second mating surface 420d is concave and the other of the first mating surface 414d and the second mating surface 420d is convex.

The first body 410d of the first portion 402d defines a first longitudinal recess 440 and a first peripheral recess 442 a. The first longitudinal recess 440 and the first peripheral recess 442a are in fluid communication. The second body 416d of the second portion 404d defines a second longitudinal recess 446 and a second peripheral recess 448 a. The second longitudinal recess 446 and the second peripheral recess 448a are in fluid communication.

The first and second

longitudinal recesses

440, 446 cooperate to define a longitudinal passage (see, e.g., longitudinal passage 452 of fig. 5A). The first and second

peripheral recesses

442a, 448a cooperate to define a peripheral receiving portion (see, e.g., peripheral receiving portion 454a of fig. 5A). Although the gearbox 400d is shown as an open gearbox, the gearbox 400d may also include walls similar to the

walls

444, 446 of the gearbox 400 of fig. 4A-4E, and the gearbox 400d is a closed gearbox. The gearbox 400d may also include a third aperture 464 and a fourth aperture 466 for receiving fasteners.

The second portion 404d may include a pin 470 and a pin 470 d. As described above in the discussion accompanying fig. 8A-8B, the annular protrusion 480 may extend around a portion of the pin 470. A pin 470d may extend from the second mating surface 420d between the proximal end or base 900 and the distal end 902. Pin 470d may include a first coupling surface 904 extending between proximal end 900 and distal end 902.

The first portion 402d may include a receiver 472 and a receiver 472 d. As described above in the discussion accompanying fig. 8A-8B, the annular recess 482 may extend around a portion of the receiver 472. The receiver 472d may extend into the first mating surface 414d from the proximal end 906 to a distal end (not shown). Receiver 472d may include a second engagement surface 910 extending between proximal end 906 and the distal end.

The receiver 472d receives the pin 470d when the gearbox 400d is in an assembled configuration or a pre-assembled configuration. The first bonding surface 904 may engage the second bonding surface 910. The gearbox 400d includes a single pre-assembled bond stop feature (e.g., annular protrusion 480 and annular recess 482). Thus, the gearbox 400d may be asymmetric about a plane extending through the central axis 912 and located between the top 914 and bottom 916 of the gearbox 400 d. Although the annular protrusion 480 and the annular recess 482 are shown on the planar first side 918, in various other implementations, the annular protrusion 480 and the annular recess 482 may alternatively be located on the planar second side 920.

Referring to FIG. 10, another gearbox 400e is illustrated. The structure and function of gearbox 400e may be substantially similar to that of gearbox 400d, with any exceptions described below and/or shown otherwise in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain the letter extension (i.e., "e") to identify those features that have been modified.

The gearbox 400e includes a first component or portion 402e and a second component or portion 404 e. A boundary or junction between the first portion 402e and the second portion 404e (see, e.g., boundary 406a of fig. 5A) defines a three-dimensional curved profile, such as a portion of one of an ellipsoid, a cone, or a sphere.

The first portion 402e includes a first body 410 e. The first body 410e includes a first exterior surface 412a and a first mating surface or first curved surface 414 e. The second portion 404e includes a second body 416 e. The second body 416e includes a second exterior surface 418a and a second mating surface or second curved surface 420 e. One of the first mating surface 414e and the second mating surface 420e is concave and the other of the first mating surface 414e and the second mating surface 420e is convex.

The first body 410e of the first portion 402e defines a first longitudinal recess 440 and a first peripheral recess 442 a. The first longitudinal recess 440 and the first peripheral recess 442a are in fluid communication. The second body 416e of the second portion 404e defines a second longitudinal recess 446 and a second peripheral recess 448 a. The second longitudinal recess 446 and the second peripheral recess 448a are in fluid communication.

The first and second

longitudinal recesses

peripheral recesses

442a, 448a cooperate to define a peripheral receiving portion (see, e.g., peripheral receiving portion 454a of fig. 5A). Although the gearbox 400E is shown as an open gearbox, in other implementations, the gearbox 400E may also include walls similar or identical to the

walls

444, 446 of the gearbox 400 of fig. 4A-4E, and the gearbox 400E is a closed gearbox. Gearbox 400e may also include third and

fourth apertures

464, 466 for receiving fasteners.

The second portion 404e may include two pins 470 d. The first portion 402d may include two receivers 472 d. The receivers 472d receive the pins 470d, respectively, when the gearbox 400e is in an assembled configuration or a pre-assembled configuration. The gearbox 400e may be symmetrical about a plane extending through the central axis 912 and located between the top 914 and bottom 916 of the gearbox 400 e. The gearbox 400e may be devoid of pre-assembled binding stop features (e.g., one or more pairs of annular protrusions 480 and annular recesses 482 as shown at least in fig. 8A-9).

Elastic layer

A gearbox according to the principles of the present invention may also include an elastomeric layer on the first and/or second mating surfaces. In various implementations, the elastic layer may be referred to as a compensating elastic element. The resilient layer facilitates accommodating relatively large manufacturing tolerances in the body of the gearbox portion, and more specifically in the mating surfaces. The elastomeric layer may be particularly beneficial when used in gearboxes without pre-assembled bond stop features (see, e.g., gearbox 400e of fig. 10), but may also be used in gearboxes with pre-assembled bond stop features (see, e.g., gearboxes 400a, 400 d). The resilient element may comprise a resilient material having a predetermined compression hardness, such as nitrile rubber.

Referring to fig. 11A through 11B, another gearbox 400f is illustrated. The structure and function of gearbox 400f may be substantially similar to that of gearbox 400e, with any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain an alphabetic extension (i.e., "f") to identify those features that have been modified.

The gearbox 400f includes a first component or portion 402e and a second component or portion 404 f. A boundary or junction 406f between the first portion 402f and the second portion 404f defines a portion of a three-dimensional curved profile, such as one of an ellipsoid, a cone, or a sphere. The first portion 402e includes a first body 410e and the second portion 404f includes a second body 416 e. The first body 410e and the second body 416e include a first mating surface 414e and a second mating surface 420e, respectively.

The second portion 404f also includes an elastic layer 1100. The resilient layer 1100 may be disposed on the second mating surface 420e, such as directly on the second mating surface 420 e. The resilient layer 1100 may be coupled to the second mating surface 420 e. The elastic layer 1100 may have a substantially uniform thickness. For example, the elastic layer 1100 may define a thickness 1102 in the range of 1mm to 1.5 mm.

In other implementations, an elastic layer may additionally or alternatively be present on the first mating surface of the second portion. The use of an elastomeric layer such as elastomeric layer 1100 may be equally applicable to open or closed gearboxes having any mating surface curvature (e.g., ellipsoidal, conical, or spherical) and having any number of pre-assembled bond stop features, including none.

Fastening piece

A gearbox assembly according to the principles of the present invention may include any of the gearboxes discussed above and a plurality of fasteners. By way of example, the fasteners may include screws, rivets, and/or bolts. The rivet may be a separate component from the gearbox portion. Additionally or alternatively, one or both of the first and second portions may include a built-in or integral rivet. The gearbox may include multiple types of fasteners, such as any combination of the fasteners described herein.

Referring to fig. 12A-12C, a gearbox assembly 1200 in accordance with the principles of the present invention is provided. The gearbox assembly 1200 includes a gearbox 400a (see fig. 5A-5B and accompanying discussion) and a plurality of fasteners 1202. The fastener 1202 may comprise a screw, such as a self-tapping screw. In some implementations, the plurality of fasteners 1202 can include four fasteners.

As best shown in fig. 12B, each fastener 1202 may include a shank 1204, a head 1206, and threads 1208 extending along at least a portion of the shank 1204. The stem 1204 may extend through the third aperture 464 and the fourth aperture 466. The head 1206 may be at least partially disposed in a counterbore 1210 in the second body 416a such that an end 1212 of the head 1206 is flush with at least a portion of the exterior surface 412a of the second body 416 a. The threads 1208 may engage the surface 1214 of the third aperture 464 to couple the first portion 402a and the second portion 404a to one another. In an assembled configuration, as shown in fig. 12C, the pin 470 and the annular protrusion 480 may be disposed in the receptacle 472 and the annular recess 482, respectively. In other implementations, the orientation of the screw 1202 may be reversed such that the head 1206 engages the first body 410a and the threads 1208 engage the second body 416 a.

While fig. 12A-12C depict a gearbox assembly 1200 including an open gearbox with ellipsoidal mating surfaces and dual pre-assembly bond stop features, the use of screws is equally applicable to assembling other gearboxes according to the principles of the present invention. For example, the gearbox assembly may include a screw and a gearbox that (i) is open or closed, (ii) has an ellipsoidal, conical, spherical, or other three-dimensional curved mating surface, (iii) includes zero, one, two, or more than two pre-assembled binding stop features, and (iv) includes an elastic layer or no elastic layer.

Referring to fig. 13A-13D, a gearbox assembly 1300 in accordance with the principles of the present invention is provided. The gearbox assembly 1300 includes a gearbox 400e (see FIG. 10 and accompanying discussion) and a plurality of fasteners 1302. The fasteners 1302 may include rivets. Each of the rivets may be a different and separable component prior to assembly and deformation. In some implementations, the plurality of fasteners 1302 can include four rivets.

As best shown in fig. 13C, each fastener 1302 may include a shank 1304 and a head 1306. The stem 1304 may include a tail 1308 configured to be crushed, upset (upset), or deformed to form a secondary head 1308' to transition the fastener 1302 from an undeformed state to a deformed state. The stem 1304 may extend through the third aperture 464 and the fourth aperture 466. The head 1306 may be at least partially disposed in a counterbore 1310 in the first body 410e such that an end 1312 of the head 1306 is flush with at least a portion of the first exterior surface 412a of the first body 410 e.

As shown in fig. 13A-13C, the tail 1308 projects beyond the second exterior surface 418a when the rivet 1302 is in an undeformed state. As shown in fig. 13D, when rivet 1302 is in the deformed state, secondary head 1308 'may be disposed in counter bore 1314 in second body 416e such that end 1316 of secondary head 1308' is flush with second outer surface 418a of second body 416 e. In the deformed state, the rivet 1302 holds the gearbox 400e in the assembled state by coupling the first portion 402e and the second portion 404e to each other. In other implementations, the orientation of the rivet 1302 may be reversed such that the head 1306 engages the second body 416e and the secondary head 1308' engages the first body 410 e.

13A-13D depict a gearbox assembly 1300 that includes an open gearbox with ellipsoidal mating surfaces and without pre-assembly bonding stop features, the use of rivets is equally applicable to the assembly of other gearboxes according to the principles of the present invention. For example, the gearbox assembly may include a rivet and a gearbox that (i) is open or closed, (ii) has an ellipsoidal, conical, spherical, or other three-dimensional curved mating surface, (iii) includes zero, one, two, or more than two pre-assembled bonding stop features, and (iv) includes an elastic layer or no elastic layer.

Referring to fig. 14A-14D, a gearbox assembly 1400 in accordance with the principles of the present invention is provided. The gearbox assembly 1400 includes a gearbox 400g with integral rivets. The structure and function of gearbox 400g may be substantially similar to that of gearbox 400a, with any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. In addition, the same reference numerals are used hereinafter and in the drawings to identify the same features, while the same reference numerals contain an alphabetic extension (i.e., "g") to identify those features that have been modified.

The gearbox 400g includes a first component or portion 402g and a second component or portion 404 g. A boundary or junction 406g between the first portion 402g and the second portion 404g defines a portion of a three-dimensional curved profile such as an ellipsoid, a cone, or a sphere. The first portion 402g includes a first body 410 g. The first body 410g includes a first exterior surface 412a and a first mating or curved surface 414 g. The second portion 404g includes a second body 416 g. The second body 416g includes a second exterior surface 418a and a second mating or curved surface 420 g. One of the first mating surface 414g and the second mating surface 420g is concave and the other of the first mating surface 414g and the second mating surface 420g is convex. The curvatures of the first mating surface 414g and the second mating surface 420g are substantially equal and opposite.

The first body 410g of the first portion 402g defines a first longitudinal recess 440 and a first peripheral recess 442 a. The first longitudinal recess 440 and the first peripheral recess 442a are in fluid communication. The second body 416g of the second portion 404g defines a second longitudinal recess 446 and a second peripheral recess 448 a. The second longitudinal recess 446 and the second peripheral recess 448a are in fluid communication. The first and second

longitudinal recesses

440, 446 cooperate to define a longitudinal passage 452 (fig. 14B). The first and second

peripheral recesses

442a, 448a cooperate to define a peripheral receptacle 454a (fig. 14B). Although the gearbox 400g is shown as an open-type gearbox, in other implementations, the gearbox 400g may include walls similar to or the same as the

walls

444, 446 of the gearbox 400 of fig. 4A-4E and may be a closed-type gearbox.

The second portion 404g may include a first pair of integral rivets 1402 and a second pair of integral rivets 1404. The first pair of rivets 1402 and the second pair of rivets 1404 can be integrally formed with the second body 416 g. The first pair of rivets 1402 and the second pair of rivets 1404 can extend from the second mating surface 420 g. The

rivets

1402, 1404 may have a circular or elliptical cross-section. In the implementation shown, the rivets 1402 of the first pair have a circular cross-section and the rivets 1404 of the second pair have an elliptical cross-section.

The first portion 402g may include a first pair of rivet openings 1406 and a second pair of rivet openings 1408. A first pair of rivet apertures and a second pair of rivet apertures may be defined in the first mating surface 414 g. The

rivet apertures

1406, 1408 can have cross-sectional shapes that match the corresponding cross-sectional shapes of the

rivets

1402, 1404. In the illustrated embodiment, the first pair of rivet apertures 1406 have a circular cross-section and the second pair of rivet apertures 1408 have an oval cross-section.

The first and second pairs of

rivet apertures

1406 and 1408, respectively, can be configured to receive the first and second pairs of

rivets

1402 and 1404. Prior to deformation, when in the pre-assembled configuration, rivets 1402, 1404 may protrude beyond first exterior surface 412a, as shown in fig. 14B-14C. In the assembled configuration, the

rivets

1402, 1404 are crushed, upset, or deformed into a deformed state. More specifically, first and second tails 1410, 1412 (fig. 14C) of the first and second pairs of

rivets

1402, 1404, respectively, can be deformed into first and second heads 1410 ', 1412' (fig. 14D), respectively. First and second heads 1410 ', 1412' may be disposed in respective first and second counter-bores 1414, 1416 in first outer surface 414 a.

In other implementations, the location of the rivet and the location of the rivet aperture may be reversed such that the first portion includes the rivet and the second portion includes the rivet aperture. In some implementations, both the first portion and the second portion include rivets and rivet apertures.

14A-14D depict a gearbox assembly 1400 including an open gearbox with dual pre-assembled binding stop features, the inclusion of an integral rivet is equally applicable to assembling other gearboxes in accordance with the principles of the present invention. For example, the gearbox assembly may include an integral rivet on the gearbox that (i) is open or closed, (ii) has an ellipsoidal, conical, spherical, or other three-dimensional curved mating surface, (iii) includes zero, one, two, or more than two pre-assembled binding stop features, and (iv) includes or is free of an elastic layer.

Gear assembly

A gearbox according to the principles of the present invention is configured to accommodate a variety of different gear assembly configurations. In various implementations, a single universal gearbox is configured to accommodate a gear system that includes any combination of the following features. For example, a gearbox in accordance with the principles of the present invention may (i) include a cross-axis single envelope gear system or a cross-axis helical gear system, (ii) be normal-strength or enhanced-strength, and (iii) be configured to operate in a range of slow speeds, a range of high speeds, or a range of ultra-high speeds.

The cross-axis single-envelope gear system includes a worm and a single-envelope gear operably engaged and configured to rotate about a vertical axis. The cross-axis single-envelope gear system may be robust and cost-effective. The cross-axis helical gear system includes a worm and a helical gear operably engaged and configured to rotate about a vertical axis. The crossed-axis helical gear system may be configured for quieter operation than a crossed-axis single-envelope gear system.

A normal strength, electrically powered length adjuster system includes a lead screw capable of withstanding an axial force of at least 19 kN. The lead screw for a normal strength, motorized length adjuster system may have a trapezoidal thread indicated by Tr 8x3(P1.5) (nominal diameter of 8mm, lead of 3mm, and pitch of 1.5 mm). An enhanced strength, electrically powered length adjuster system includes a lead screw capable of withstanding an axial force of at least 25 kN. The lead screw of the electro-dynamic length adjuster system for enhanced strength may have a trapezoidal thread defined by Tr 9x3(P1.5) (nominal diameter of 9mm, lead of 3mm, and pitch of 1.5 mm).

The speed classification may be achieved by a combination of gear ratios and motor parameters (e.g., speed). In various implementations, a gearbox according to principles of the present invention may accommodate a gear system having a linear adjustment speed in a range from 17mm/s to 85 mm/s. In one implementation, the relaxation speed system may be configured to have an average linear adjustment speed in a range from 17mm/s to 22 mm/s. The slow speed system may have a maximum electric motor rotation speed of about 3,900 rpm. The slow speed system may have a gear ratio of at least 6.5: 1. In another implementation, the high speed system may be configured to have an average linear adjustment speed in a range from 50mm/s to 55 mm/s. The high speed system may have a maximum electric motor rotational speed of about 4,900 rpm. The high speed system may have a gear ratio of at least 3.333: 1. In yet another implementation, the ultra-high speed system may be configured, for example, to have an average linear adjustment speed in a range from 80mm/s to 85 mm/s. The ultra-high speed system may have a maximum electric motor rotational speed of about 6,900 rpm. The ultra-high speed system may have a gear ratio of at least 2.6: 1.

A universal gearbox according to the principles of the present invention may accommodate any combination of the above gear types, strengths, and speeds. That is, a single gearbox design may be provided in an assembly setup to subsequently accommodate any combination of the above options. Example implementations are described below.

Referring to fig. 15A-15D, an adjustment assembly 24h in accordance with the principles of the present invention is provided. The structure and function of the adjustment assembly 24h may be substantially similar to that of the adjustment assembly 24 (fig. 1-3), with the exception of any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. Moreover, the same reference numerals are used below and in the drawings to indicate similar features, while the same reference numerals are used to include the letter extension (i.e., "h") to indicate those features that have been modified.

The adjustment assembly 24h includes a spindle or lead screw 56h having external threads 66h and an adjustment subassembly 58 h. The adjustment subassembly 58h includes: a first gear or barrel worm 80h having a helical external thread 82h, a second gear or enveloping worm 86h having external teeth 84h and an internal thread 90h, a pair of support bushings 78, and a gearbox assembly 1200. The gearbox assembly 1200 includes a gearbox 400a and a plurality of fasteners 1202. The gearbox 400a includes a first portion 402a and a second portion 404 a. Although not shown, the adjustment subassembly 58h may also include a support frame (e.g., the support frame 74 of fig. 1-3) and a pair of enclosures (e.g., the first enclosure 116 and the second enclosure 118 of fig. 1-3). The adjustment assembly 24h may alternatively include any other gearbox assembly described herein.

The thread 66h of the spindle screw 56h may be trapezoidal and defined by Tr 9x3(P1.5) (nominal diameter 9mm, lead 3mm, and pitch 1.5 mm). The adjustment assembly 24h may have a minimum axial strength of 25kN and be considered as an adjustment assembly of increased strength. The second gear 86h may be a single wrap worm gear. Thus, the adjustment assembly 24h may be viewed as having a cross-axis, single-pack gear system. The adjustment assembly 24h may be configured via gear ratios and motor parameters as a slow speed system.

Referring to fig. 16A-16E, an adjustment assembly 24i in accordance with the principles of the present invention is provided. The structure and function of the adjustment assembly 24i may be substantially similar to that of the adjustment assembly 24 (fig. 1-3), with the exception of any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. Moreover, the same reference numerals are used below and in the drawings to indicate the same features, while the same reference numerals, including the letter extension (i.e., "i"), are used to indicate those features that have been modified.

The adjustment assembly 24i includes a spindle or lead screw 56h having external threads 66h and an adjustment subassembly 58 i. The adjustment subassembly 58i includes: a first gear or barrel worm 80i having a helical external thread 8i2, a second or helical gear 86i having external teeth 84i and an internal thread 90i, a pair of bearing bushings 78, a pair of washers 1600, a gearbox assembly 1200, a pair of

housings

116, 118, and a support frame 74. The gearbox assembly 1200 includes a gearbox 400a and a plurality of fasteners 1202. Gearbox 400a includes a first portion 402a and a second portion 404 a. The adjustment assembly 24i may alternatively include any other gearbox assembly described herein.

The helical gear 86i includes two cylindrical bearing surfaces 162 i. The outer teeth 84i extend in the space between the bearing surfaces 162 i. Each washer 1600 is disposed on a respective one of the bearing surfaces 1602 between the outer tooth 84i and a respective one of the bearing bushings 78. Each washer 1600 includes a retention feature, such as a protrusion 1604 that engages the helical gear 86. The protrusion 1604 may slow or prevent the washer 1600 from rotating relative to the helical gear 86 i.

The adjustment assembly 24i includes a spindle screw 56h having a thread 66h defined by Tr 9x3(P1.5) (nominal diameter 9mm, lead 3mm, and pitch 1.5 mm). The adjustment assembly 24i may have a minimum axial strength of 25kN and be considered an enhanced strength adjustment assembly. The second gear 86i may be a helical gear. Thus, the adjustment assembly 24i may be considered as having a cross-axis helical gear system. The adjustment assembly 24i may be configured as a slow speed system via gear ratios and motor parameters.

Referring to fig. 17A-17D, an adjustment assembly 24j in accordance with the principles of the present invention is provided. The structure and function of the adjustment assembly 24j may be substantially similar to the structure and function of the adjustment assembly 24 (fig. 1-3) with the exception of any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. Moreover, the same reference numerals are used below and in the drawings to indicate similar features, while the same reference numerals, including the letter extension (i.e., "j"), are used to indicate those features that have been modified.

The adjustment assembly 24j includes a spindle or lead screw 56j having external threads 66j and an adjustment subassembly 58 j. The adjustment subassembly 58j includes: a first gear or barrel worm 80j having a helical external thread 82j, a second gear or enveloping worm 86j having external teeth 84j and an internal thread 90j, a pair of support bushings 78, and a gearbox assembly 1200. The gearbox assembly 1200 includes a gearbox 400a and a plurality of fasteners 1202. The gearbox 400a includes a first portion 402a and a second portion 404 a. The adjustment assembly 24j may alternatively include any other gearbox assembly described herein. Although not shown, the adjustment subassembly 58j may also include a support frame (e.g., the support frame 74 of fig. 1-3) and a pair of enclosures (e.g., the first enclosure 116 and the second enclosure 118 of fig. 1-3).

The thread 66j of the spindle screw 56j may be trapezoidal and defined by Tr 8x3(P1.5) (nominal diameter of 8mm, lead of 3mm, and pitch of 1.5 mm). The adjustment assembly 24j may have a minimum axial strength of 19kN and be considered a normal strength adjustment assembly. The second gear 86j may be a single wrap worm gear. Thus, the adjustment assembly 24j may be considered as having a cross-axis, single-envelope, orthogonal gear system. The adjustment assembly 24j may be configured as a high speed system via a gear ratio and a motor speed.

Referring to fig. 18A-18D, an adjustment assembly 24k in accordance with the principles of the present invention is provided. The structure and function of the adjustment assembly 24k may be substantially similar to that of the adjustment assembly 24 (fig. 1-3), with any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. Moreover, the same reference numerals are used below and in the drawings to indicate similar features, while the same reference numerals, including the letter extension (i.e., "k"), are used to indicate those features that have been modified.

The adjustment assembly 24k includes a spindle or lead screw 56j having external threads 66j and an adjustment subassembly 58 k. The adjustment subassembly 58k includes: a first gear or barrel worm 80k having a helical external thread 82k, a second gear or enveloping worm 86k having external teeth 84j and an internal thread 90k, a pair of support bushings 78, a pair of washers 1600, and a gearbox assembly 1200. The gearbox assembly 1200 includes a gearbox 400a and a plurality of fasteners 1202. The gearbox 400a includes a first portion 402a and a second portion 404 a. The adjustment assembly 24k may alternatively include any other gearbox assembly described herein. Although not shown, the adjustment subassembly 58k may also include a support frame (e.g., the support frame 74 of fig. 1-3) and a pair of enclosures (e.g., the first enclosure 116 and the second enclosure 118 of fig. 1-3).

The thread 66j of the spindle screw 56j may be trapezoidal and defined by Tr 8x3(P1.5) (nominal diameter of 8mm, lead of 3mm, and pitch of 1.5 mm). The adjustment assembly 24j may have a minimum axial strength of 19kN and be considered a normal strength adjustment assembly. The second gear 86k may be a single wrap worm gear. Thus, the adjustment assembly 24k may be considered to have a cross-axis, single-envelope gear system. The adjustment assembly 24k may be configured as a high speed system.

Referring to fig. 19A-19D, an adjustment assembly 24m in accordance with the principles of the present invention is provided. The structure and function of the adjustment assembly 24m may be substantially similar to that of the adjustment assembly 24 (fig. 1-3), except for any exceptions described below and/or otherwise shown in the figures. Accordingly, the structure and/or function of like features will not be described in detail. Additionally, the same reference numerals are used below and in the drawings to indicate the same features, while the same reference numerals containing a letter extension (i.e., "m") are used to indicate those features that have been modified.

The adjustment assembly 24m includes a spindle or lead screw 56j having external threads 66j and an adjustment subassembly 58 m. The adjustment subassembly 58m includes: a first gear or barrel worm 80j having a helical external thread 82j, a second gear or enveloping worm 86m having external teeth 84m and an internal thread 90m, a pair of support bushings 78, a pair of washers 1600, and a gearbox assembly 1200. The gearbox assembly 1200 includes a gearbox 400a and a plurality of fasteners 1202. The gearbox 400a includes a first portion 402a and a second portion 404 a. The adjustment assembly 24m may alternatively include any of the other gearbox assemblies described herein. Although not shown, the adjustment subassembly 58m may also include a support frame (e.g., the support frame 74 of fig. 1-3) and a pair of enclosures (e.g., the first enclosure 116 and the second enclosure 118 of fig. 1-3).

The thread 66j of the spindle screw 56j may be trapezoidal and defined by Tr 8x3(P1.5) (nominal diameter of 8mm, lead of 3mm, and pitch of 1.5 mm). The adjustment assembly 24j may have a minimum axial strength of 19kN and be considered a normal strength adjustment assembly. The second gear 86m may be an enveloping worm gear. Thus, the adjustment assembly 24k may be considered as having an envelope orthogonal gear system. The conditioning assembly 24m may be configured as an ultra high speed system.

In accordance with the principles of the present invention, an electric length adjustment assembly may include a gear box assembly, a gear system, and a spindle screw. The gearbox assembly may include a gearbox and a plurality of fasteners. The gearbox may be an open gearbox or a closed gearbox. The gearbox may comprise two parts or portions having mating surfaces with a three-dimensional curvature, such as an ellipsoidal, conical or spherical curvature. The fasteners may include screws (e.g., self-tapping screws), rivets (e.g., breakaway rivets, integral rivets), bolts, or any combination thereof. The gear system may be an envelope quadrature gear system or a helical quadrature gear system. The gear system may be configured as a slow speed system, a high speed system or an ultra high speed system. The spindle screw may be a normal strength lead screw or an enhanced strength lead screw.

The foregoing description of embodiments has been presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment even if not specifically shown or described. The various elements or features of a particular embodiment may also be varied in a number of different ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.

Claims

1. A gearbox for a vehicle seat adjustment mechanism, the gearbox comprising:

a first portion comprising a first body defining a first longitudinal recess and a first peripheral recess in fluid communication with the first longitudinal recess, and the first body comprising a first curved surface that is concave; and

a second portion comprising a second body defining a second longitudinal recess and a second peripheral recess in fluid communication with the second longitudinal recess, and the second body comprising a second curved surface that is convex and has an equal and opposite curvature as compared to the first curved surface, wherein, in an assembled configuration:

the first curved surface is in contact with the second curved surface,

the first longitudinal recess communicates with the second longitudinal recess to define a longitudinal passage, and

the first peripheral recess communicates with the second peripheral recess to define a peripheral receptacle.

2. The gearbox as set forth in claim 1, wherein both of said first and second curved surfaces define: (i) a portion of an ellipsoidal surface, (ii) a portion of a conical surface, or (iii) a portion of a spherical surface.

3. The gearbox of claim 1, wherein both the first curved surface and the second curved surface define a portion of an ellipsoidal surface having a first radius in a range of 190mm to 200mm and a second radius in a range of 240mm to 250 mm.

4. The gearbox as set forth in claim 1, wherein both of said first and second curved surfaces define a portion of a conical surface defining an average opening angle in the range of 165 ° to 172 °.

5. The gearbox as set forth in claim 1, wherein both of said first and second curved surfaces define a portion of a spherical surface having a radius in the range of 190mm to 200 mm.

6. The gearbox of claim 1, wherein:

one of the first portion and the second portion comprises a frustoconical protrusion extending from a respective one of the first curved surface and the second curved surface,

the other of the first and second portions includes a frustoconical receptacle defined by a respective one of the first and second curved surfaces, and

in the assembled configuration, the frustoconical receiver receives the frustoconical protrusion.

7. The gearbox of claim 6, wherein:

the one of the first portion and the second portion further comprising an annular protrusion extending from the respective one of the first curved surface and the second curved surface, the annular protrusion disposed around a base of the frustoconical protrusion and coaxial with the frustoconical protrusion,

the other of the first and second portions further comprises an annular recess defined by a respective one of the first and second curved surfaces, the annular recess being coaxial with the frustoconical receiver and

in the assembled configuration, the annular recess receives the annular protrusion.

8. The gearbox as set forth in claim 7, wherein said frustoconical protrusion comprises a first frustoconical protrusion and a second frustoconical protrusion, said frustoconical receiver comprises a first frustoconical receiver and a second frustoconical receiver, said annular protrusion comprises a first annular protrusion and a second annular protrusion, and said annular recess comprises a first annular recess and a second annular recess.

9. The gearbox of claim 1, further comprising:

an elastic layer disposed on at least one of the first curved surface or the second curved surface.

10. The gearbox of claim 1, wherein:

one of the first and second portions comprises an integral rivet extending from a respective one of the first and second curved surfaces, and

the other of the first portion and the second portion includes an aperture defined in a respective one of the first curved surface and the second curved surface, the aperture configured to receive a portion of the integral rivet.

11. The gearbox of claim 1, further comprising:

a plurality of fasteners configured to couple the first portion and the second portion to one another.

12. The gearbox of claim 1, wherein:

the gear box is configured to house at least a portion of the spindle screw and the cross-axis gear system, and

the cross-axis gear system includes a first gear operatively coupled with a second gear operatively coupled with the spindle screw.

13. The gearbox as recited in claim 12, wherein said gear system is configured to operate in one of:

(i) a relaxation speed with a linear adjustment speed in the range from 17mm/s to 22mm/s,

(ii) high speed with a linear adjustment speed in the range from 50mm/s to 55mm/s, or

(iii) Ultra high speed with linear regulation speed in the range from 80mm/s to 85 mm/s.

14. The gearbox of claim 12, wherein the first gear is a cylindrical worm gear and the second gear is one of a helical gear or a single wrap worm gear.

15. A vehicle seat adjustment assembly comprising:

a gearbox assembly, the gearbox assembly comprising:

a first portion including a first body defining a first longitudinal recess and a first peripheral recess in fluid communication with the first longitudinal recess, and

the first body comprises a first curved surface, the first curved surface being concave; and

a second portion comprising a second body defining a second longitudinal recess and a second peripheral recess, and the second body comprising a second curved surface, the second longitudinal recess cooperating with the first longitudinal recess to define a longitudinal passageway, the second peripheral recess cooperating with the first peripheral recess to define a peripheral receptacle, the second curved surface being convex, the second curved surface having an equal and opposite curvature as compared to the first curved surface, and the second curved surface being in contact with the first curved surface;

a gear system, the gear system comprising:

a first gear disposed at least partially within the peripheral receptacle, the first gear including a first external thread, the first gear configured to rotate about a first axis, an

A second gear disposed at least partially within the longitudinal passageway, the second gear including external teeth and internal threads and defining a gear passageway, the external teeth operatively coupled with the first external threads, the second gear configured to rotate about a second axis perpendicular to the first axis; and

a spindle screw extending through the gear passage and including a second external thread operatively coupled with the internal thread.

16. The vehicle seat adjustment assembly of claim 15 wherein the first and second curved surfaces both define (i) a portion of an ellipsoidal surface, (ii) a portion of a conical surface, or (iii) a portion of a spherical surface.

17. The vehicle seat adjustment assembly of claim 15 wherein the second gear is one of (i) a helical gear or (ii) a single wrap worm gear.

18. The vehicle seat adjustment assembly of claim 15 wherein:

the second external thread is a trapezoidal thread, and

the spindle screw has a lead of 3mm, a pitch of 1.5mm, and one of (i) a nominal diameter of 8mm and (ii) a nominal diameter of 9 mm.

19. The vehicle seat adjustment assembly of claim 15 wherein the gear system is configured to operate in one of:

20. The gearbox assembly of claim 15, wherein:

one of the first and second portions includes a frustoconical protrusion and an annular protrusion extending from a respective one of the first and second curved surfaces, the annular protrusion disposed about a base of the frustoconical protrusion and coaxial with the frustoconical protrusion,

the other of the first and second portions includes a frustoconical receptacle defined by a respective one of the first and second curved surfaces and an annular recess coaxial with the frustoconical receptacle and

the frustoconical receiving portion is configured to receive the frustoconical protrusion and the annular recess is configured to receive the annular protrusion.