A stator includes a stator body member and a fixing member. The stator body member includes a first disc part, a plurality of first stator blades and a first ratchet portion. The plurality of first stator blades extend outward from the first disc part in a radial direction. The first ratchet portion is provided on a principal surface of the first disc part so as to extend in a circumferential direction. The fixing member is disposed in a non-rotatable state, and includes a second disc part and a second ratchet portion. The second ratchet portion is provided on a principal surface of the second disc part so as to extend in the circumferential direction, and is configured to be engaged with the first ratchet portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No. 2017-093838 filed on May 10, 2017, the entirety of which is hereby incorporated by reference in its entirety.

BACKGROUND

Technical Field

The present disclosure relates to a stator for a torque converter.

BACKGROUND INFORMATION

A torque converter includes an impeller, a turbine and a stator (e.g., Japan Laid-open Patent Application Publication No. 2016-211716). The stator is attached to a stator shaft, which is non-rotatable, through a one-way clutch. Therefore, the stator is configured to be rotated only in one direction.

An outer race is disposed between the one-way clutch and the stator so as to prevent the stator from deforming due to a load applied thereto through the one-way clutch.

BRIEF SUMMARY

It is an object of the present disclosure to provide a stator that can reduce the number of components relevant thereto.

A stator according to an aspect of the present disclosure includes a stator body member and a fixing member. The stator body member includes a first disc part, a plurality of first stator blades and a first ratchet portion. The plurality of first stator blades extend outward from the first disc part in a radial direction. The first ratchet portion is provided on a principal surface of the first disc part so as to extend in a circumferential direction. The fixing member includes a second disc part and a second ratchet portion. The second ratchet portion is provided on a principal surface of the second disc part so as to extend in the circumferential direction. The second ratchet portion is configured to be engaged with the first ratchet portion. The fixing member is disposed in a non-rotatable state.

According to this configuration, with engagement between the first ratchet portion and the second ratchet portion, the stator body member is rotated in one direction without being rotated in the other direction. Additionally in this configuration, a load is hardly applied to the stator in the radial direction because rotation of the stator is restricted by the engagement of the first ratchet portion provided on the principal surface of the first disc part and the second ratchet portion provided on the principal surface of the second disc part. Therefore, it is possible to omit providing an outer race, whereby the number of components relevant to the stator can be reduced.

Preferably, the stator further includes an urging member. The urging member urges the fixing member toward the stator body member in an axial direction.

Preferably, the fixing member further includes a tubular part. Additionally, the second disc part extends outward from the tubular part in the radial direction.

Preferably, the stator further includes a retainer. The retainer includes a third disc part and a plurality of second stator blades extending outward from the third disc part in the radial direction. Additionally, the plurality of respective first stator blades and the plurality of respective second stator blades are aligned in the circumferential direction.

Preferably, at least a pair of the first and second stator blades disposed adjacently to each other in the circumferential direction partially overlaps in an axial view.

Preferably, the stator body member further includes a first engaging portion. The first engaging portion is disposed outside the first ratchet portion in the radial direction. Additionally, the first engaging portion is provided on the principal surface of the first disc part so as to extend in the circumferential direction. The retainer further includes a second engaging portion. The second engaging portion is provided on a principal surface of the third disc part and is engaged with the first engaging portion.

Overall, according to the stator of the present disclosure, the number of components relevant thereto can be reduced.

DETAILED DESCRIPTION OF EMBODIMENTS

An exemplary embodiment of a stator according to the present disclosure will be hereinafter explained with reference to the attached drawings. It should be noted that in the following explanation, the term “axial direction” indicates an extending direction of a rotational axis O of the stator. On the other hand, the term “circumferential direction” indicates a circumferential direction of an imaginary circle about the rotational axis O, whereas the term “radial direction” indicates a radial direction of the imaginary circle about the rotational axis O. The term “radially outside” indicates a side separating from the rotational axis O in the radial direction, whereas the term “radially inside” indicates a side approaching to the rotational axis O in the radial direction.

As shown inFIGS. 1 to 3, a stator100includes a stator body member1, a fixing member2and a retainer3. The stator100is rotatable about the rotational axis O. The stator body member1and the retainer3are fixed to each other, and are unitarily rotated. It should be noted that the fixing member2is not rotated. The stator body member1is disposed on a first side of the retainer3in the axial direction, whereas the retainer3is disposed on a second side of the stator body member1in the axial direction. The fixing member2is disposed between the stator body member1and the retainer3.

As shown inFIG. 4, the stator body member1includes a first disc part11, a first ratchet portion12, a first engaging portion13, a plurality of first stator blades14and an outer tubular part15. The first disc part11, the first ratchet portion12, the first engaging portion13, the plural first stator blades14and the outer tubular part15are provided as a single member. For example, the stator body member1can be molded with a die by, for instance, casting, resin molding, compression molding or so forth.

First Disc Part

The first disc part11has a disc shape and includes a through hole111in the middle thereof. Each of the principal surfaces of the first disc part11faces in the axial direction. Of the principal surfaces of the first disc part11, the surface facing the second side in the axial direction, in other words, the surface facing the fixing member2and the retainer3, is provided with the first ratchet portion12and the first engaging portion13.

First Ratchet Portion

The first ratchet portion12is provided on the principal surface of the first disc part11so as to extend in the circumferential direction. The first ratchet portion12is opposed to a second ratchet portion22to be described. Moreover, the first ratchet portion12is engaged with the second ratchet portion22only in an opposite direction to a rotational direction of the stator body member1. Therefore, the stator body member1is rotated only in a predetermined direction but is not rotated in the opposite direction to the predetermined direction.

Specifically, the first ratchet portion12is composed of a plurality of first slopes121aligned on the principal surface of the first disc part11in the circumferential direction. Each first slope121reduces in height along the circumferential direction. It should be noted that the height of each first slope121means the axial dimension thereof. A step is formed in a boundary region of each adjacent pair of the first slopes121. The step is engaged with a step formed in a boundary region of each adjacent pair of second slopes221of the second ratchet portion22.

First Engaging Portion

The first engaging portion13extends on the principal surface of the first disc part11in the circumferential direction. The first engaging portion13is disposed radially outside the first ratchet portion12. Specifically, the first engaging portion13is provided on the outer peripheral end portion of the first disc part11. The first engaging portion13protrudes further than the first ratchet portion12in the axial direction. Similarly to the first ratchet portion12, the first engaging portion13is composed of a plurality of third slopes131. Each third slope131has a longer circumferential length than each first slope121.

First Stator Blades

The respective first stator blades14extend radially outward from the outer peripheral surface of the first disc part11. The respective first stator blades14are disposed at intervals from each other in the circumferential direction.

Each first stator blade14extends in the radial direction. Detailedly, each first stator blade14extends between the first disc part11and the outer tubular part15in the radial direction. Each first stator blade14has a plate shape and slants such that the principal surfaces thereof face not only in the axial direction but also in the circumferential direction. The thickness of each first stator blade14gradually reduces toward the first side in the axial direction.

The entirety of the radially outer end surface of each first stator blade14is disposed within the inner peripheral surface of the outer tubular part15. On the other hand, part of the radially inner end surface of each first stator blade14protrudes from the outer peripheral surface of the first disc part11to the second side in the axial direction. The part of the radially inner end surface of each first stator blade14makes contact with the outer peripheral surface of a third disc part31of the retainer3.

Outer Tubular Part

The outer tubular part15has a cylindrical shape and extends in the axial direction. The outer tubular part15includes a plurality of grooves151on the inner peripheral surface thereof. Each groove151is disposed between each pair of the first stator blades14located adjacently to each other in the circumferential direction. Each groove151slants to extend not only in the axial direction but also in the circumferential direction. The width of each groove151gradually reduces toward the first side in the axial direction.

As shown inFIGS. 1 to 3, the fixing member2is disposed in a non-rotatable state. Specifically, the fixing member2is fixed to a stator shaft of a torque converter (not shown in the drawings).FIG. 5is a perspective view of the fixing member2as seen from the first side in the axial direction. As shown inFIG. 5, the fixing member2includes a second disc part21, the second ratchet portion22and a tubular part23.

Second Disc Part

The second disc part21has a disc shape and the principal surfaces thereof face in the axial direction. Of the principal surfaces of the second disc part21, the surface facing the first side in the axial direction, in other words, the surface facing the stator body member1, is provided with the second ratchet portion22.

FIG. 6is a perspective view of the fixing member2assembled to the stator body member1. As shown inFIG. 6, the second disc part21has a smaller outer diameter than the first disc part11. The second disc part21is accommodated in a space delimited by the first engaging portion13.

Second Ratchet Portion

As shown inFIG. 5, the second ratchet portion22is provided on the principal surface of the second disc part21so as to extend in the circumferential direction. The second ratchet portion22is configured to be engaged with the first ratchet portion12. As described above, the first ratchet portion12and the second ratchet portion22are engaged only in the predetermined rotational direction but are not engaged in the opposite rotational direction to the predetermined rotational direction.

Specifically, the second ratchet portion22is composed of the plural second slopes221aligned on the principal surface of the second disc part21in the circumferential direction. Each second slope221reduces in height along the circumferential direction. It should be noted that the height of each second slope221means the axial dimension thereof. A step is formed in a boundary region of each adjacent pair of the second slopes221. The step is engaged with the step formed in the boundary region of each adjacent pair of the first slopes121of the first ratchet portion12.

Tubular Part

The tubular part23has a cylindrical shape and extends in the axial direction. The second disc part21extends radially outward from the outer peripheral surface of the tubular part23. The tubular part23includes spline grooves on the inner peripheral surface thereof. When the tubular part23and the stator shaft are spline-coupled, the fixing member2is fixed to the stator shaft in a non-rotatable state.

FIG. 7is a perspective view of the retainer3as seen from the first side in the axial direction. As shown inFIG. 7, the retainer3includes the third disc part31, a plurality of second stator blades32and a second engaging portion33. The third disc part31, the respective second stator blades32and the second engaging portion33are provided as a single member. For example, the retainer3can be molded with a die by, for instance, casting, resin molding, compression molding or so forth.

Third Disc Part31

The third disc part31has a disc shape and includes a through hole311in the middle thereof. The tubular part23of the fixing member2penetrates the through hole311of the third disc part31.

The principal surfaces of the third disc part31face in the axial direction. Of the principal surfaces of the third disc part31, the surface facing the first side in the axial direction, in other words, the surface facing the stator body member1, is provided with the second engaging portion33.

The outer peripheral surface of the third disc part31and that of the first disc part11are substantially flush to each other. In other words, the outer diameter of the third disc part31and that of the first disc part11are substantially equal to each other.

FIG. 8is a perspective view of the retainer3to which the fixing member2is assembled. As shown inFIG. 8, the outer diameter of the third disc part31is greater than that of the second disc part21of the fixing member2. The second disc part21is accommodated in a space delimited by the second engaging portion33. In other words, the second disc part21is accommodated in the space delimited by the first engaging portion13and the second engaging portion33.

Second Engaging Portion

As shown inFIG. 7, the second engaging portion33extends on the principal surface of the third disc part31in the circumferential direction. Specifically, the second engaging portion33is provided on the outer peripheral end portion of the third disc part31. The second engaging portion33protrudes from the third disc part31in the axial direction. The second engaging portion33is engaged with the first engaging portion13in the circumferential direction. Similarly to the first engaging portion13, the second engaging portion33is composed of a plurality of fourth slopes331.

Second Stator Blades

Each second stator blade32extends in the radial direction. Detailedly, each second stator blade32extends radially outward from the outer peripheral surface of the third disc part31. Each second stator blade32has substantially the same shape as each first stator blade14and also has substantially the same size as each first stator blade14. Part of the radially inner end surface of each second stator blade32protrudes from the outer peripheral surface of the third disc part31to the first side in the axial direction. Additionally, the part of the radially inner end surface of each second stator blade32makes contact with the outer peripheral surface of the first disc part11.

The respective second stator blades32are disposed at intervals from each other in the circumferential direction. As shown inFIGS. 1 and 2, the respective first stator blades14and the respective second stator blades32are aligned in the circumferential direction. Preferably, the respective first stator blades14and the respective second stator blades32are alternately aligned in the circumferential direction.

The circumferential length of each second stator blade32is longer than the interval between adjacent two of the first stator blades14. Therefore, as shown inFIGS. 1 and 9, each pair of the first and second stator blades14and32, disposed adjacently to each other in the circumferential direction, partially overlaps in an axial view. In other words, each adjacent pair of the first and second stator blades14and32overlaps at the adjacent circumferential end portions thereof in the axial view. Therefore, any interval is not produced between each adjacent pair of the first and second stator blades14and32in the axial view.

As shown inFIG. 2, the radially outer end portion of each second stator blade32is disposed within each groove151of the outer tubular part15of the stator body member1. The stator body member1and the retainer3are positioned to each other with the configuration that the radially outer end portion of each second stator blade32is disposed within each groove151.

The retainer3, configured as described above, is fixed to the stator body member1, and hence, is unitarily rotated with the stator body member1. Detailedly, the retainer3is joined to the stator body member1.

For example, the radially outer end surface of each second stator blade32and the inner peripheral surface of the outer tubular part15can be joined to each other. Additionally or alternatively, part of the radially inner end surface of each second stator blade32and the outer peripheral surface of the first disc part11can be joined to each other, and or alternatively, part of the radially inner end surface of each first stator blade14and the outer peripheral surface of the third disc part31can be joined to each other. Still additionally or alternatively, the first disc part11and the third disc part31can be joined to each other. It should be noted that a heretofore known method such as frictional press-contact can be employed as a joint method.

One exemplary embodiment of the present advancement has been described above. However, the present advancement is not limited to this, and a variety of changes can be made without departing from the gist of the present advancement.

For example, in the aforementioned exemplary embodiment, the first stator blades14and the second stator blades32are alternately aligned. However, alignment of the first and second stator blades14and32is not particularly limited to this.

Additionally, in the aforementioned exemplary embodiment, each first stator blade14and each second stator blade32are configured to have substantially the same shape and the same size. However, the shape and size configuration of each first stator blade14and that of each second stator blade32are not particularly limited to this. In other words, each first stator blade14and each second stator blade32can have different shapes and different sizes.

As shown inFIG. 10, the stator100can further include an urging member4. The urging member4urges the fixing member2toward the stator body member1in the axial direction. The urging member4is, for instance, a disc spring.