Torque converter with spherical coupling

Abstract

A torque converter arrangement (10) comprising a rotational axis (A), a first (60) and a second sphere center arranged along the rotational axis (A), a pump impeller (18) with a pump impeller housing (16, 116) having a first spherical surface (160), wherein the first spherical surface (160) has a radius (65) defining a first curvature, the first sphere center (60) and a first friction surface (162), a turbine (20) with a turbine housing (22) having a second spherical surface (170), wherein the second spherical surface (170) has the radius (64) defining a second curvature approximately corresponding to or equal to the first curvature, the second sphere center, and a second friction surface (172), wherein the first and second friction surfaces (162, 172) are arranged to form a frictional connection.

Description

TECHNICAL AREA The invention relates generally to a torque converter with a spherical clutch assembly. BACKGROUND OF THE INVENTION US Publication US 2015 / 0021137, which is hereby incorporated by reference into the present description, describes a two-pass multi-function torque converter with an elastic element for opening an impeller clutch. US Publication US 2012 / 0152680, which is hereby incorporated by reference into the present description, discloses an embodiment in which a first friction surface has an axial curvature in a section of the friction surface located between a first inner diameter and a first outer diameter, wherein the axial curvature is defined by an arc whose radius is at least one order of magnitude larger than a radial distance between the inner diameter and the outer diameter. Further torque converters with friction clutches are known from the publications JP H03 - 157 520 A , DE 102 36 533 A1 , DE 10 2013 202 661 A1 , DE 196 26 685 A1 , DE 27 13 661 A1 and US 2007 / 0 289 830 A1. BRIEF SUMMARY Exemplary embodiments generally comprise a clutch assembly comprising an axis of rotation, a first and a second spherical center arranged along the axis of rotation, a first element having a first spherical surface with a radius defining a first curvature (the first spherical center), and a first friction surface, a second element having a second spherical surface with a radius defining a second curvature (the second curvature being approximately equal to or identical with the first curvature, the second spherical center), and a second friction surface. In one embodiment, the second spherical center is approximately equal to or identical with the first spherical center when the clutch is engaged. In another embodiment, the second spherical center is offset from the first spherical center when the clutch is disengaged.In one embodiment, the first spherical surface further comprises a large circle having radius and the first sphere center, wherein the first and second friction surfaces are arranged along the large circle to form a frictional connection. In another embodiment, the first or second element comprises a friction material, wherein the first or second friction surface is arranged on the friction material. In another embodiment, the friction material has a connecting surface and an opposing surface. In another embodiment, the opposing surface is convex. Further embodiments generally relate to a torque converter comprising an axis of rotation, a first and a second spherical center arranged along the axis of rotation, a pump impeller with a pump impeller housing comprising a first inner spherical surface with a radius defining a first curvature (the first spherical center) and a first friction surface, and a turbine with a turbine housing comprising a second inner spherical surface with a radius defining a second curvature approximately corresponding to or identical with the first curvature (the second spherical center) and a second friction surface, wherein the first and second friction surfaces are arranged to form a frictional connection. In one embodiment, the pump impeller housing or the turbine housing comprises friction material, wherein the first or second friction surface is arranged on this friction material.In one embodiment, the friction material has a connecting surface and an opposing surface. In one embodiment, the opposing surface is convex. In one embodiment, the impeller housing comprises a first spherical section comprising the first inner spherical surface, an outer surface of the rear cover, and a first thickness. In one embodiment, the impeller housing further comprises a first and a second inclined section and a second thickness greater than the first thickness. In one embodiment, the impeller housing further comprises a cylindrical section with an end section, wherein the cylindrical section extends toward a cover and is configured to connect to it, and a curved section extending toward a torus section of the impeller housing and integrally attached to it.In one embodiment, the turbine housing comprises a second spherical section, which has the second inner spherical surface and an outer surface of the turbine housing. In another embodiment, the turbine housing further comprises a radial wall section that extends to and is integrally attached to a torus section of the turbine housing. In another embodiment, the first spherical surface further comprises a large circle having the radius and the first spherical center, wherein the first and second friction surfaces are arranged along the large circle to form a frictional connection. One embodiment generally relates to a torque converter comprising an axis of rotation, a first and a second spherical center arranged along the axis of rotation, a cover, a pump impeller with a pump impeller housing, wherein the pump impeller housing comprises a first spherical section with a first inner spherical surface, a radius defining a first curvature, the first spherical center, and a first friction surface, and a curved section, and a cylindrical section with an end section extending towards the cover and connectable to it, a turbine with a turbine housing, wherein the turbine housing comprises a second spherical section with a second inner spherical surface, which has a second curvature defining a second curvature approximately corresponding to or identical with the first curvature, the second spherical center, and a second friction surface.wherein the first and second friction surfaces are arranged to form a frictional connection, wherein the second sphere center point is approximately the same as or identical to the first sphere center point when the clutch is engaged, and wherein the second sphere center point is offset from the first sphere center point when the clutch is disengaged. In one embodiment, the first spherical surface further comprises a large circle having the first radius and the first sphere center point, wherein the first and second friction surfaces are arranged along the large circle to form a frictional connection. In one embodiment, the first or the second spherical section comprises friction material, wherein the first or second friction surface is arranged on the friction material. BRIEF DESCRIPTION OF THE DRAWINGS The nature and function of the present invention are explained in more detail in the following comprehensive description of the invention with reference to the accompanying drawings. These show: Fig. 1 a partial cross-sectional side view of a torque converter with a spherical coupling assembly in an exemplary embodiment, Fig. 2 a cross-sectional side view of the torque converter shown in Fig. 1 in a position rotated about the axis of rotation A in an exemplary embodiment, Fig. 3 a partial side view of a torque converter with a spherical coupling assembly in an exemplary embodiment according to box B in Fig. 1, Fig. 4 a partial side view of a spherical coupling assembly with the coupling engaged in an exemplary embodiment, and Fig. 5 a partial side view of a spherical coupling assembly with the coupling disengaged in an exemplary embodiment. DETAILED DESCRIPTION It should be noted at the outset that identical or functionally similar elements and structures in the various drawings and views have the same reference numerals. Furthermore, the present invention is naturally variable in many respects and is not limited to the specific embodiments, methods, materials, and variations described herein. It should also be noted that the present invention is defined exclusively by the appended claims and that the terminology used herein serves only to describe certain aspects and should in no way be interpreted as limiting the present invention. Unless otherwise defined, the technical and scientific terms used herein are to be understood in accordance with their generally accepted meanings as apparent to a person skilled in the art in the field of the invention. Although any methods, devices, or materials similar or equivalent to those described herein may be used in connection with the practical application or testing of the invention, exemplary methods, devices, and materials are described below. A spherical clutch assembly designed according to the present disclosure offers various advantages, such as compensation for misalignments while simultaneously reducing torus size. A spherical clutch assembly is suitable, for example, for use in torque converters. Misalignment of components during operation can lead to undesirable torque fluctuations. The spherical clutch described here is self-centering. A smaller torus size for torque converters and the associated reduction in the overall weight of the assembly are desirable in modern vehicles for reducing fuel consumption. The following description refers to Figures 1-5. Figure 1 shows a partial sectional side view of a torque converter with a spherical coupling assembly according to an exemplary embodiment. The torque converter 10 is also referred to in this document as the torque converter assembly. The torque converter 10 comprises a front cover 12 for connection to a crankshaft of an internal combustion engine via a bolt 11, and a rear cover 16 of a pump impeller 18, also referred to as the impeller housing. Pump impellers are alternatively referred to as impellers. The front cover 12 and the rear cover 16 are connected to each other at a weld 14. The cover 12 includes a journal section 90. The torque converter 10 further comprises a turbine 20, a turbine housing 22, and a guide vane 32 between the turbine 20 and the pump impeller 18. Turbines and pump impellers are known to comprise a plurality of blades.The torque converter 10 comprises a torus section 75, which generally includes the hydraulic coupling section with the turbine 20 and the pump wheel 18 between the dashed lines in Fig. 1. The torque converter 10 comprises a freewheel clutch 30, against which the guide wheel 32 is supported, as well as an inner running surface 88, a roller 92, and an outer running surface 94. A side plate 36 holds the freewheel clutch 30 in position within the guide wheel 32. Furthermore, the torque converter 10 comprises a damper assembly 40, which is connected to and driven by the turbine 20 and is located between the turbine 20 and the front cover 12. The damper assembly 40 comprises a spring 42, a flange 46, and a drive finger 44 attached to the turbine housing 22 on the damper assembly 40. As will be explained in more detail with reference to Figures 3-5, the torque converter 10 comprises a clutch assembly 50. As shown in Figure 1, the torque converter 10 further comprises a hub 80 attached to the flange 46, a bushing 86, a weld 96, and a hub 98. Figure 1 also shows a toothed section 78, an input shaft 82, and a stator shaft 84 as transmission components. The hub 80 is toothed with the input shaft 82, with the inner running surface 88 being toothed with the stator shaft 84 via the toothed section 78. The bushing 86 serves to position and at least partially seal the turbine housing 22 on the shaft 82. The torque converter 10 has an axis of rotation A, also referred to simply as axis A, as well as a spherical center 60 and a radius 65. Some components of the torque converter 10 have a spherical surface, the geometric contour or surface shape of which corresponds to at least a segment of a sphere, the sphere being defined by its center and radius. The spherical center 60 is located at the intersection of the radius 65 with the axis of rotation A. The radius 65 is the distance between the spherical center 60 and a segment of the clutch assembly 50. More precisely, the radius 65 is the distance between the spherical center 60 and the first spherical surface of the clutch assembly 50, which is shown in more detail in Figs. 3-5. The first axial direction AD1 runs opposite to the second axial direction AD2. Fig. 2 is a cross-sectional side view of the exemplary embodiment of a torque converter shown in Fig. 1 in a position rotated about the axis of rotation A. Fig. 2 shows the elements of the torque converter shown in Fig. 1 as well as a large circle 70. The large circle 70 represents a circle of the sphere with the sphere's center 60 and radius 65. A plane passing through the large circle 70 divides the sphere into two equal parts. The clutch assembly 50 is designed to engage along the large circle 70. Figures 3-5 are partial side views of a torque converter of a spherical clutch assembly according to box B in Figure 1 in an exemplary embodiment. In the enlarged views of Figures 3-5, the center of the sphere 60 and the radius 65 are not visible, but are present as shown in Figure 1. Figures 3-5 are simply enlarged versions of Figure 1 for clarity. The spherical clutch assembly is also referred to as the clutch assembly in this document. Figure 3 shows a clutch assembly 150 with a first element or, according to an exemplary embodiment, a rear cover 116. The first element or the rear cover 116 comprises a first spherical section 152, a curved section 154, and a cylindrical section 156 with an end section 158. The end section 158 is connected to the cover 112 at a weld 114 in a known manner.The spherical section 152 comprises a first spherical surface 160, also referred to as the first inner spherical surface, wherein a portion of the first spherical surface 160 has a first friction surface 162. The spherical section 152 further comprises an outer surface 164 of the rear cover opposite the first inner spherical surface 160. The coupling assembly 150 further comprises a second element, or, according to an exemplary embodiment, an extension of the turbine housing 122, with a second spherical section 166 and a radial wall section 168. The spherical section 166 comprises a second spherical surface 170, also referred to as the second inner spherical surface 170, wherein the second spherical surface 170 has a second friction surface 172. Figures 3-5 further show sections of the flange 148 and the spring 142. The following explanations refer generally to Figures 1-5 and in particular to Figures 4-5. The clutch assembly 250, 350 shown here comprises a pivot axis A and a first and a second spherical center point positioned along the pivot axis. Figure 4 is a partial side view of an embodiment of a spherical clutch assembly 250 with the clutch engaged, while Figure 5 is a partial side view of an embodiment of a spherical clutch assembly 350 with the clutch disengaged. The disengagement distance of the clutch assembly 350 is shown greatly enlarged for clarity. Depending on the clutch state, the second spherical center point is located at or near the spherical center point 60 on axis A. In other words, with the clutch assembly 250 engaged, the second spherical center point is located at the same point as the first spherical center point 60. Furthermore, with the clutch assembly 250 disengaged, the second spherical center point is located at the spherical center point 60.With the clutch assembly 350 disengaged, the second ball center 60 is offset in the second axial direction AD2 along axis A relative to the first ball center 60. Thus, when the clutch is disengaged, the second ball center moves axially away from the torus section 75 in a direction parallel to axis A. The second ball center is not shown in the drawings because the magnitude of the axial movement is relatively small, approximately in the millimeter range, so that the ball centers in Fig. 1 and Fig. 2 would be indistinguishable. Referring again to Figs. 1-5, the clutch assembly 150, according to one embodiment, comprises the axis of rotation A, the first and second spherical centers, the first element 116 with a first spherical surface 160 having a radius 65 defining a first curvature, and the first spherical center 60, wherein the first spherical surface 160 has a first friction surface 162. The clutch assembly 150 further comprises a second element 122 with a second spherical surface 170, which has a radius 65 defining a second curvature approximately corresponding to or identical with the first curvature, wherein the second spherical center can coincide with the first spherical center 60 when the clutch is engaged, or, when the clutch is disengaged, can be arranged offset from the first spherical center 60 along the axis A in the axial direction AD2, i.e., away from the torus section 75.In other words, when the clutch is engaged, the center point of the second ball is approximately identical or the same as the center point of the first ball, and when the clutch is disengaged, the center point of the second ball is offset from the center point of the first ball. The spherical surface 170 encompasses the second friction surface 172. The first spherical surface 160 further encompasses a large circle 70 with radius 65 and the first sphere center 60, wherein the first and second friction surfaces 162, 172 are arranged along the large circle 60 to form a frictional connection. Due to the engagement of the clutch along the large circle 70, the clutch assembly 150 is self-centering and thus provides continuous torque output and uniform contact at the friction surfaces. Compensation for misalignments between the transmission input shaft 82 and the axis of rotation A is achieved, with clutch components being aligned within the large circle 70. The second element – ​​in one embodiment, the turbine housing 122 – comprises a friction material 174 with a connecting surface 176 and an opposing surface 178. It is clear to those skilled in the art that, although the second element is described here as the element with the friction material 174, the friction material 174 is not limited to the first element, but can be arranged on either the first or the second element. In other words, a friction material 174 on the first element is also conceivable and could, for example, be attached to an inner surface of a pump impeller housing. The second friction surface 172 is arranged on the friction material 174. In one embodiment, the second friction surface 172 is arranged on the opposing surface 178. When applying a friction material to an element using a punch, it is known to be possible to adapt the shape of the opposing surface 178 by adjusting the thickness of the friction material 174 and the shape of the element onto which the friction material is applied. In one embodiment, the element 122 comprises the outer surface 184 of the turbine housing and the inner surface 186 of the turbine housing. In one embodiment, the inner surface 186 can have a spherical or planar shape before the application of the friction material 174. In both cases, however, the second inner spherical surface 170 is spherical. This is achieved as follows: If the surface 186 is planar, the friction material 174 has a convex thickness profile to ensure that the spherical surface 170 remains spherical. In other words, the opposing surface 178 is convex.In another embodiment, where the surface 186 is spherical, the friction material 174 has a uniform thickness, so that the surface 170 is also spherical according to the surface 186. Another embodiment relates to a torque converter with a spherical clutch assembly.The torque converter 10 comprises: a rotational axis A; a first and second sphere center arranged along the rotational axis; a pump impeller 18 with a pump impeller housing 16, 116, which has a first inner spherical surface 160 with the radius 65 defining a first curvature, the first sphere center 60 and a first friction surface 162; a turbine 20 with a turbine housing 22, 122, which has a second inner spherical surface 170 with the radius 64 defining a second curvature approximately equal to or identical with the first curvature and the second sphere center (displaced in the axial direction AD2 to the first sphere center when the clutch is disengaged and coinciding with the first sphere center 60 when the clutch is engaged); and the second friction surface 172, wherein the first and second friction surfaces 162, 172 are arranged to form a frictional connection.The second element 22, 122 comprises a friction material 174, wherein the second friction surface 172 is arranged on the friction material 174. The friction material 174 comprises a connecting surface 176 and an opposing surface 178. In one embodiment, the opposing surface 178 is convex. In another embodiment, the first spherical surface 160 further comprises the large circle 70 with radius 65 and the first spherical center 60, wherein the first and second friction surfaces are arranged along the large circle 70 to form a frictional connection. In one embodiment, the first element 116 comprises a first spherical section 152 with a first inner spherical surface 160, an outer surface 164 of the rear cover, and a first thickness t1. In another embodiment, the first element 116 further comprises a first and a second inclined section 180, 182, and a second thickness t2, wherein t2 is at least as large as or greater than t1. The first spherical section 152 need not be inclined; various designs or arrangements of the transition regions between the spherical section 152 and the adjacent sections, i.e., the cylindrical section 156 and the curved section 154, are possible. In another embodiment, the first element comprises a cylindrical section 156 with an end section 158, wherein the cylindrical section 156 extends towards the cover 112 and is arranged to be connectable to it.In one embodiment, the first element comprises a curved section 154, which extends towards the torus section 75 of the pump impeller housing 116, which is also referred to as the pump impeller housing torus section, and is integrally attached to it. In one embodiment, the second element 122 comprises the second spherical section 166 with the second inner spherical surface 170 and an outer surface 184 of the turbine housing. In another embodiment, the second element 122 further comprises a radial wall section 168 that extends to and is integrally attached to a torus section 75 of the turbine housing 122, which is also referred to as the turbine housing torus section. In yet another exemplary embodiment, the torque converter 10 comprises a rotational axis A, a first and second spherical center arranged along the rotational axis, the covers 12, 112, the impeller 18 with the impeller housing 16, 116, wherein the impeller housing 16, 116 has a spherical section 152 with a first inner spherical surface 160 having a radius 65 defining a first curvature, the first spherical center 60, the first friction surface 162, the curved section 154, the cylindrical section 156 with the end section 158 extending towards and connectable to the covers 12, 112, the turbine with the turbine housing 22, 122 having the second inner spherical surface 170, wherein the second inner spherical surface 170 defines a second curvature approximately corresponding to or identical with the first curvature.the second sphere center (displaced axially in the direction AD2 relative to the first sphere center 60 when the clutch is disengaged, and coinciding with the first sphere center when the clutch is engaged), and the second friction surface 172, wherein the first and second friction surfaces 162, 172 are arranged to form a frictional connection. In other words, when the clutch is engaged (Fig. 4), the second sphere center is approximately the same as or identical to the first sphere center 60, and when the clutch is disengaged (Fig. 5), the second sphere center is displaced relative to the first sphere center. In an exemplary embodiment, the first spherical surface 160 further comprises a large circle 70 with a radius 65 and the first sphere center 60, wherein the first and second friction surfaces 162,172 are arranged along or aligned with the large circle 70 to form a frictional connection. In an exemplary embodiment, the second element 22, 122 comprises a friction material 174, wherein the second friction surface 172 is arranged on the friction material 174. Naturally, modifications and variations of the above examples of the invention are apparent to those skilled in the art, without departing from the scope of the invention defined by the claims. Although the invention has been described with reference to specific preferred and / or exemplary embodiments, it is obvious that variations are possible without deviating from the scope and extent of the invention defined by the claims.

Claims

A torque converter arrangement (10) comprising a rotational axis (A), a first (60) and a second sphere center arranged along the rotational axis (A), a pump impeller (18) with a pump impeller housing (16, 116) having a first spherical surface (160), wherein the first spherical surface (160) has a radius (65) defining a first curvature, the first sphere center (60) and a first friction surface (162), a turbine (20) with a turbine housing (22) having a second spherical surface (170), wherein the second spherical surface (170) has the radius (64) defining a second curvature approximately corresponding to or equal to the first curvature, the second sphere center, and a second friction surface (172), wherein the first and second friction surfaces (162, 172) are arranged to form a frictional connection. A torque converter arrangement (10) comprising a rotational axis (A), a first (60) and a second spherical center arranged along the rotational axis (A), a cover (12), a pump impeller (18) with a pump impeller housing (16, 116), wherein the pump impeller housing (16, 116) has a first spherical section (152) with a first spherical surface (160) having a radius (65) defining a first curvature, the first spherical center (60) and a first friction surface (162) and a curved section (154), and a cylindrical section (156) with an end section (158) extending to and connectable with the cover (12), a turbine (20) with a turbine housing (22), wherein the turbine housing (22) has a second spherical section (166) with a second spherical surface (170) having the radius (65) defining a first curvature, the first spherical center (60) and a first friction surface (162) and a curved section (154), and a cylindrical section (156) with an end section (158) extending to and connectable with the cover (12), a turbine (20) with a turbine housing (22), wherein the turbine housing (22) has a second spherical section (166) with a second spherical surface (170) having a radius (65) defining a second approximately corresponding to or identical with the first curvature, having a second center of the sphere and a second friction surface (172),wherein the first and second friction surfaces (162, 172) are arranged to form a frictional connection, wherein the second ball center point corresponds approximately to or is identical with the first ball center point (60) when the clutch is engaged, and wherein the second ball center point is offset from the first ball center point (60) when the clutch is disengaged. The arrangement according to claim 1, wherein the second ball center when the clutch is engaged corresponds approximately to or is identical with the first ball center (60), and wherein the second ball center is offset from the first ball center (60) when the clutch is disengaged. The arrangement according to claim 1 or 2, wherein the first spherical surface (160) further comprises a large circle (70) having the radius (65) and the first sphere center (60), and wherein the first and second friction surfaces (162, 172) are arranged along the large circle (70) to form a frictional connection. The arrangement according to claim 1 or 2, further comprising friction material (174), wherein the first or second friction surface (162, 172) is arranged on the friction material (174). The arrangement according to claim 5, wherein the friction material (174) has a connecting surface (176) and an opposing surface (178). The arrangement according to claim 6, wherein the opposite surface (178) is convex. The torque converter arrangement (10) according to claim 1, wherein the pump impeller housing (16, 116) comprises a first spherical section (152) with the first inner spherical surface (160), an outer surface (164) of the rear cover (16) and a first thickness (t1). The torque converter arrangement (10) according to claim 8, wherein the pump wheel housing (16, 116) further comprises a first and a second inclined section (180, 182) and a second thickness (t2), wherein the second thickness (t2) is greater than the first thickness (t1).

Images