WO2018152720A1

WO2018152720A1 - Transmission fork position sensor arrangement

Info

Publication number: WO2018152720A1
Application number: PCT/CN2017/074532
Authority: WO
Inventors: Shangchun PAN
Original assignee: Hamlin Electronics (Suzhou) Co. Ltd
Priority date: 2017-02-23
Filing date: 2017-02-23
Publication date: 2018-08-30

Abstract

The sensor arrangement (100) may be used in a transmission (102) associated with a vehicle. In one implementation, the sensor arrangement (100) is used to ascertain a position of a fork (600) within a transmission (102). The sensor arrangement (100) may include a sensor assembly (106) and a magnet assembly (104). The sensor assembly (106) may be coupled to a fixed portion of the transmission (102). For example, the sensor assembly (106) may be coupled to a wall or cover of the transmission (102). The magnet assembly (104) may be coupled to a fork (600) within the transmission (102), or a portion of the fork (600), such as a body portion associated with the fork (600). The magnet assembly (104) may house four separate magnets.

Description

TRANSMISSION FORK POSITION SENSOR ARRANGEMENT

BACKGROUND Field

The present disclosure generally relates to sensors and sensor assemblies. In particular, the present disclosure relates to sensor and sensor assemblies used in vehicle transmissions.

Description of Related Art

Transmissions, such as those used in vehicles, include forks that move gear elements. For example, one or more forks may be implemented in a transmission to deselect one gear and select another gear during a gear shift process. A fork that moves a gear element may be movably mounted to a shaft, such as a shift shaft. The fork is designed to move at least laterally relative to an axis of the shift shaft. It may be beneficial to obtain position information of the fork to achieve smooth shifting operation of the transmission.

Conventional position sensor assemblies used to determine a position of a fork disposed in a transmission generally use a single magnet arrangement to enable determining the position of the fork. However, the single magnet arrangement requires the use of a large magnet. Such a large magnet is costly to procure. Furthermore, the large magnets used with single magnet position sensor arrangements may interfere with other position sensors deployed in close proximity.

Other problems with existing sensors and sensor assemblies will become apparent in view of the disclosure below.

SUMMARY

This Summary is provided to introduce a selection of concepts in a simplified form further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is this Summary intended as an aid in determining the scope of the claimed subject matter.

According to one implementation, a magnet assembly may include a body. Four cavities may be defined in the body. A first magnet may be disposed in a first of the four cavities, a second magnet may be disposed in a second of the four cavities, a third magnet may be disposed in a third cavity of the four cavities, and a fourth magnet may be disposed in a fourth of the four cavities.

According to another implementation, an apparatus may include a fork to move a transmission member disposed within a vehicle transmission, and a body coupled to the fork. The apparatus may further include four cavities defined in the body. A first magnet may be disposed in a first of the four cavities, a second magnet may be disposed in a second of the four cavities, a third magnet may be disposed in a third cavity of the four cavities, and a fourth magnet may be disposed in a fourth of the four cavities.

According yet another implementation, a method may include providing a fork to arrange in a vehicle transmission, and mounting a magnet assembly to the fork. The magnet assembly may include a body and four cavities defined in the body. A first magnet may be disposed in a first of the four cavities, a second magnet may be disposed in a second of the four cavities, a third magnet may be disposed in a third cavity of the four cavities, and a fourth magnet may be disposed in a fourth of the four cavities.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a sensor arrangement, according to an exemplary embodiment of this disclosure.

FIG. 2 illustrates the magnet assembly, according to an exemplary embodiment of this disclosure.

FIG. 3 illustrates another view of the magnet assembly, according to an exemplary embodiment of this disclosure.

FIG. 4 illustrates a view of the magnet assembly with the magnets disposed therein, according to an exemplary embodiment of this disclosure.

FIG. 5 illustrates a view of the magnet assembly with an epoxy covering the magnets disposed therein, according to an exemplary embodiment of this disclosure.

FIG. 6 illustrates a view of the magnet assembly coupled to a fork that may be disposed within a transmission, according to an exemplary embodiment of this disclosure.

FIG. 7 illustrates a process, according to an exemplary embodiment of this disclosure.

DETAILED DESCRIPTION

A sensor arrangement is disclosed. The sensor arrangement may be used in a transmission associated with a vehicle. In one implementation, the sensor arrangement is used to ascertain a position of a fork within a transmission. The sensor arrangement may include a sensor assembly and a magnet assembly. The sensor assembly may be coupled to a fixed portion of the transmission. For example, the sensor assembly may be coupled to a wall or cover of the transmission. The magnet assembly may be coupled to a fork within the transmission, or a portion of the fork, such as a body portion associated with the fork.

The fork may be coupled to a shaft or rail member of the transmission. In one implementation, the fork is coupled to the shaft or rail member of the transmission by way of the body portion. The fork may be actuated to move along the shaft or rail member of the transmission. Because the magnet assembly is coupled to the fork, or portion of the fork, the magnet assembly moves with the fork. Therefore, the sensor assembly, which is fixed to a portion of the transmission, in concert with the magnet assembly, may be used to ascertain a position/movement of the fork relative to the shaft or rail member of the transmission.

An exemplary embodiment of the magnet assembly includes four magnets disposed therein. The magnet assembly including four magnets is less costly to manufacture than conventional magnet assemblies that use a single large magnet. Furthermore, compared to conventional magnet assemblies that use a single large magnet, the magnetic field of the magnet assembly including the four magnets, according to this disclosure, is less likely to interfere with other sensor arrangements implemented in close proximity to the magnet assembly including the four magnets. In an implementation, the magnet assembly including four magnets includes two magnets having a first size and two magnets having a second size, where the first size is larger than the second size. In a particular implementation, the two magnets having the first size are disposed away from a center of the magnet assembly, and the two magnets having the second size are disposed adjacent to the center of the magnet assembly.

FIG. 1 illustrates a sensor arrangement 100, according to an exemplary embodiment of this disclosure. The sensor arrangement 100 may be an integral part of a transmission 102 associated with a vehicle (not shown) . The sensor arrangement 100 may include a magnet assembly 104 and a sensor assembly 106. The sensor assembly 106 may house a magnet effect sensor, such as a Hall-effect sensor, anisotropic magneto-resistive sensor, giant magnetoresistance sensor, or tunnel magnetoresistance sensor. As described hereinafter, the magnet assembly 104 may house a plurality of magnets.

The sensor assembly 106 may be fixed to a housing or cover of the housing associated with the transmission 102. Therefore, the sensor assembly 106 may be disposed within the transmission 102 in an unmovable state. In one implementation, the sensor assembly 106 is fixed to the housing of the transmission 102 by way of a bolt or other fastener inserted in a hole 108 and coupled to the housing or cover of the housing associated with the transmission 102. A positioning post 114 may be associated with the sensor assembly 106. The positioning post 114 may be received in a hole in the housing or cover of the housing associated with the transmission 102. The positioning post 104 is used to properly align the sensor assembly 106 on the housing or cover the housing associated with the transmission 102.

The magnet assembly 104 may be attached to a movable part within the transmission 102. In one implementation, the magnet assembly 104 is attached to the movable part by way of a bolt or other fastener inserted in a hole 110. In one implementation, an arrow 112 illustrates the movable directions of the magnet assembly 104 in the coupled arrangement with the movable part within the transmission 102. The sensor assembly 106 is disposed to ascertain movement and position related information related to the movable part, via the magnet assembly 104 attached to the movable part.

FIG. 2 illustrates the magnet assembly 104, according to an exemplary embodiment of this disclosure. The magnet assembly 104 may be made from a plastic material, or other synthetic or semi-synthetic material that is moldable to form a solid object. The magnet assembly 104 may include a first cavity 200, a second cavity 202, a third cavity 204, and a fourth cavity 206. In one implementation, a first recessed wall 208 separates the first cavity 200 and the third cavity 204, and a second recessed wall 210 separates the second cavity 202 and the fourth cavity 206.

The magnet assembly 104 includes a notch 212 disposed in a wall 214 of the magnet assembly 104. Furthermore, a notch 216 is disposed in the wall 214. The magnet assembly 104 may include a first post 218 and a second post 220. Each of the first post 218 and the second post 220 may include a plurality of ribs 222. In one implementation, the first post 218 includes two ribs 222 spaced over a surface of the first post 218. In another implementation, the second post 220 includes four ribs 222 spaced over a surface of the second post 220.

FIG. 3 illustrates another view of the magnet assembly 104, according to an exemplary embodiment of this disclosure. In particular, FIG. 3 illustrates a first magnet 300, a second magnet 302, a third magnet 304, and a fourth magnet 306. The first magnet 300 is for insertion into the first cavity 200； the second magnet 302 is for insertion into the second cavity 202； the third magnet 304 is for insertion into the third cavity 204； and the fourth magnet 306 is for insertion into the fourth cavity 206. In one implementation, the magnets 300-306 may have an equal size and/or shape. In a particular implementation, the

magnets

300 and 302 have an equal size and/or shape, and the

magnets

304 and 306 have an equal size and/or shape. In one implementation, the

magnets

300 and 302 are larger than the

magnets

304 and 306. In one implementation, the

magnets

300 and 302 are sized with the dimensions 5.1mm x 5.1mm x 3mm (length x width x height) , and the

magnets

304 and 306 are sized with the dimensions 2.7mm x 2.7mm x 3mm (length x width x height) .

FIG. 4 illustrates a view of the magnet assembly 104 with the magnets 300-306 disposed therein, according to an exemplary embodiment of this disclosure. In particular, the first magnet 300 is disposed in the first cavity 200； the second magnet 302 is disposed in the second cavity 202； the third magnet 304 is disposed in the third cavity 204； and the fourth magnet 306 is disposed in the fourth cavity 206.

FIG. 5 illustrates a view of the magnet assembly 104 with an epoxy 500, or other suitable material, covering the magnets 300-306 disposed therein, according to an exemplary embodiment of this disclosure. The epoxy 500 covers the magnets 300-306 and at least partially fills the cavities 200-206. In a particular implementation, the epoxy 500 partially fills the cavities 200-206 such that a surface 502 of the epoxy 500 is below a surface 504. It may be advantageous to partially fill the cavities 200-206 with the epoxy 500, as illustrated, so that the epoxy 500 does not disrupt contact of the surface 504 to the movable part of the transmission 102. Specifically, maintaining a good flatness of the surface 504 ensures that the surface 504 is in consistent contact to the movable part (e.g., fork) of the transmission 102 when the magnet assembly 104 is coupled to the movable part. The

notches

212 and 216 are provided to allow overflow of the epoxy 500 from the cavities 200-206 during a process of injecting the epoxy 500 into the cavities 200-206. Therefore, the

notches

212 and 206 may aid in safeguarding that the epoxy 500 remains below the surface 504 during the process of injecting the epoxy 500 into the cavities 200-206 and during hardening of the epoxy 500.

FIG. 6 illustrates a view of the magnet assembly 104 coupled to a fork 600 that may be disposed within the transmission 102, according to an exemplary embodiment of this disclosure. The magnet assembly 104 is fixed to the fork 600 using a bolt 602 that engages a hole 604 in the fork 600.

The first post 218 and the second post 220 may be used to align the magnet assembly 104 on the fork 600 in advance of fixing the magnet assembly 104 to the fork 600 using the bolt 602. Proper alignment of the magnet assembly 104 on the fork 600 ensures that movement and position of the magnet assembly 104 and the fork 600 may be accurately observed by the sensor assembly 106.

In a particular implementation, the first post 218 is pressed into a hole 606 in the fork 600, and the second post 220 is pressed into a hole 608, prior to engaging the bolt 602 with the hole 604. The first post 218 and the second post 220 ensure that the magnet assembly 104 is properly aligned on the fork 600 in advance of engaging the bolt 602 with the hole 604. In one implementation, the plurality of ribs 222, disposed on the first post 218 and the second post 220, aid to ensure that the first post 218 is properly aligned in the hole 606 and that the second post 220 is properly aligned in the hole 608. In one particular implementation, proper alignment of the magnet assembly 104 on the fork 600 is achieved when the first post 218 includes two ribs 222 spaced over a surface of the first post 218, and the second post 220 includes four ribs 222 spaced over a surface of the second post 220.

FIG. 7 illustrates a process 700, according to an exemplary embodiment of this disclosure. The process 700 may involve the use of one or more of the structural elements illustrated in FIGS 1-6. For example, the process 700 may involve the use of the magnet assembly 104, the sensor assembly 106 and/or the fork 600.

At block 702, a fork is provided to arrange in a transmission, such as a vehicle transmission. At block 704, the magnet assembly is mounted to the fork.

While exemplary sensor arrangements are disclosed, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the claims of the application. Other modifications may be made to adapt a particular situation or material to the teachings disclosed above without departing from the scope of the claims. Therefore, the claims should not be construed as being limited to any one of the particular embodiments disclosed, but to any embodiments that fall within the scope of the claims.

Claims

A magnet assembly, comprising:

a body；

four cavities defined in the body； and

a first magnet disposed in a first of the four cavities, a second magnet disposed in a second of the four cavities, a third magnet disposed in a third cavity of the four cavities, and a fourth magnet disposed in a fourth of the four cavities.
The magnet assembly according to claim 1, wherein the first magnet and the second magnet are larger than the third magnet and the fourth magnet.
The magnet assembly according to claim 2, wherein a size of the first magnet and the second magnet is the same and a size of the third magnet in the fourth magnet is the same.
The magnet assembly according to claim 1, wherein a size of the first magnet and the second magnet is 5.1mm x 5.1mm x 3mm (length x width x height) and a size of the third magnet and the fourth magnet is 2.7mm x 2.7mm x 3mm (length x width x height) .
The magnet assembly according to claim 1, comprising a first recessed wall and a second recessed wall disposed in the body, the first recessed wall separating the first and third cavities and the second recessed wall separating the second and fourth cavities.
The magnet assembly according to claim 5, comprising a first notch disposed in a wall adjacent to the first cavity and a second notch disposed in a wall adjacent to the second cavity.
The magnet assembly according to claim 1, comprising a first post and a second post disposed on a surface of the body.
The magnet assembly according to claim 7, wherein the first post has an outer surface having a plurality of ribs spaced over the outer surface of the first post and the second post has an outer surface having a plurality of ribs spaced over the outer surface of the second post.
The magnet assembly according to claim 7, wherein the first post has an outer surface having two ribs spaced over the outer surface of the first post and the second post has an outer surface having four ribs spaced over the outer surface of the second post.
An apparatus, comprising:

a fork to move a transmission member disposed within a vehicle transmission；

a body coupled to the fork；

four cavities defined in the body； and

a first magnet disposed in a first of the four cavities, a second magnet disposed in a second of the four cavities, a third magnet disposed in a third cavity of the four cavities, and a fourth magnet disposed in a fourth of the four cavities.
The apparatus according to claim 10, wherein the first magnet and the second magnet are larger than the third magnet and the fourth magnet.
The apparatus according to claim 10, comprising a first recessed wall and a second recessed wall disposed in the body, the first recessed wall separating the first and third cavities and the second recessed wall separating the second and fourth cavities.
The apparatus according to claim 12, comprising a first notch disposed in a wall adjacent to the first cavity and a second notch disposed in a wall adjacent to the second cavity.
The apparatus according to claim 10, comprising a first post and a second post disposed on a surface of the body.
The apparatus according to claim 14, wherein the first post has an outer surface having a plurality of ribs spaced over the outer surface of the first post and the second post has an outer surface having a plurality of ribs spaced over the outer surface of the second post.
The apparatus according to claim 15, wherein the first post has an outer surface having two ribs spaced over the outer surface of the first post and the second post has an outer surface having four ribs spaced over the outer surface of the second post.
The method, comprising:

providing a fork to arrange in a vehicle transmission； and

mounting a magnet assembly to the fork, the magnet assembly comprising:

a body；

four cavities defined in the body； and

a first magnet disposed in a first of the four cavities, a second magnet disposed in a second of the four cavities, a third magnet disposed in a third cavity of the four cavities, and a fourth magnet disposed in a fourth of the four cavities.
The method according to claim 17, wherein the magnet assembly comprises a first post and a second post disposed on a surface of the body, wherein the first post has an outer surface having a plurality of ribs spaced over the outer surface of the first post and the second post has an outer surface having a plurality of ribs spaced over the outer surface of the second post.
The method according to claim 18, wherein the first post has an outer surface having two ribs spaced over the outer surface of the first post and the second post has an outer surface having four ribs spaced over the outer surface of the second post.
The method according to claim 17, wherein a size of the first magnet and the second magnet is the same and a size of the third magnet in the fourth magnet is the same, and the size of the first magnet and the second magnet is larger than the size of the third magnet and the fourth magnet.