Coupling system with a ratchet arrangement

Abstract

Coupling arrangement, which includes: a sleeve configured to at least partially surround a hub in the circumferential direction; and a detent arrangement located in the hub, configured to hold the sleeve and hub in a defined axial position, and which includes: a first opening containing a ball and a spring; and a holding device that holds the spring and the ball in the first opening; the ball engages with a notch in the sleeve.

Description

TECHNICAL FIELD

[0001] The present description generally relates to a detent system for a clutch assembly. More specifically, the present disclosure relates to a detent system having balls and springs held in an opening of a hub via a retaining device. BACKGROUND AND SUMMARY

[0002] Vehicles may have a transmission that allows the speed to be adjusted depending on the transmission input and output. Some transmissions have a multi-stage design, where individual gears are engaged and disengaged via clutches to vary the match between the input and output speeds of the transmission. Some clutches include hubs, sleeves, and components that restrict movement between the hub and sleeve.

[0003] The applicant has identified several problems with previous coupling arrangements. For example, some previous couplings require the individual coupling components to be mounted sequentially on a shaft. This sequence of coupling assembly can be comparatively slow and laborious, and in some cases can lead to incorrect or incomplete installation of the coupling due to misplaced or lost components.

[0004] The problems described above can be solved by a coupling assembly. In one example, the coupling assembly includes a sleeve configured to at least partially circumferentially surround a hub. The coupling assembly further includes a detent assembly disposed in the hub and configured to hold the sleeve and hub in a specific axial position. The detent assembly includes an opening with a ball and a spring therein, and a retainer that holds the spring and ball in the opening. In the coupling assembly, the ball engages a detent in the sleeve. Constructing the coupling assembly in this manner allows at least a portion of the coupling to be preassembled and then efficiently installed as an assembled unit on a shaft, if desired.As a result, the likelihood of improper coupling installation, as well as component misplacement and loss, is reduced, increasing efficiency and confidence in manufacturing.

[0005] In one example, the retaining device may also be a retaining ring. In such an example, the retaining ring may include a tab that restricts (e.g., prevents) rotation of the retaining ring, and in some cases, the tab may engage with a second opening. In this way, the ball and spring are securely and effectively retained within the hub opening. In one example, the opening is a through-hole. The use of a through-hole allows for further simplification of the assembly's manufacturing and installation.

[0006] In one example, the retaining device may also be a bushing. Using a bushing in the clutch assembly allows the spring and ball to be securely held in the opening, further reducing the likelihood of the ball and spring becoming dislodged from their intended position in the hub opening.

[0007] It should be understood that the above summary is intended to introduce, in simplified form, a selection of concepts that are further explained in the detailed description. It is not intended to identify the most important or essential features of the claimed subject matter, the scope of which is clearly defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that address the disadvantages noted above or elsewhere in this disclosure. SHORT DESCRIPTION OF THE CHARACTERS Fig. 1 shows an example of a vehicle system with a transmission. Fig. Figure 2 shows a cross-sectional view of an example of a transmission with a clutch that includes a detent arrangement. Fig. 3 and Fig. 4 show cross-sectional views of the notch arrangement from Fig. 2. Fig. 5 shows another cross-sectional view of the coupling from Fig. 2. Fig. 6 and Fig. 7 show detailed representations of a spring and a ball in the detent arrangement of Fig. 2. Fig. 8 shows another example of a detent arrangement in a clutch. DETAILED DESCRIPTION

[0008] Fig. 1 shows a schematic diagram of a vehicle 50 having a drivetrain 51, which may include a prime mover 54 and a transmission 60 (e.g., a geared transmission). In some examples, prime mover 54 may be an electric motor (a traction motor). In such an example, the electric motor may be electrically connected to an energy storage device 58 (e.g., one or more traction batteries, capacitors, fuel cells, combinations thereof, and the like). Furthermore, in the electric motor example, the motor may be configured to operate as a generator under certain conditions, for example, to provide electrical power to charge energy storage device 58. In such an example, the drivetrain may include an inverter electrically connected to the energy storage device and the traction motor. In other examples, prime mover 54 may be an internal combustion engine.Thus, in various examples, the vehicle 50 may be a hybrid vehicle, a pure electric vehicle, or a vehicle with an internal combustion engine.

[0009] In the illustrated example, the transmission 60 supplies mechanical power to a differential 62 of an axle assembly 53. However, it should be understood that in other examples, the transmission 60 may additionally or alternatively supply mechanical power to another axle assembly 64 in the vehicle 50. In still other examples, the transmission may be incorporated into one of the axles to form an electric axle assembly. In a specific example, a hybrid vehicle may be included, having an electric drive axle and another axle powered by an internal combustion engine. However, powertrains with a variety of architectures are contemplated.

[0010] The transmission 60 may be configured to receive torque from the prime mover 54, for example, via a shaft (e.g., a drive shaft) and / or other suitable mechanical component. The transmission 60 may include at least one clutch 61. The clutch may be a disconnect clutch or, for example, a clutch for shifting between gears. The clutch 61 in the transmission 60 may be actuated via an actuator 63 (e.g., a shift fork actuator or other suitable actuator).

[0011] In addition, the transmission 60 can deliver mechanical power to the differential 62. The output torque can be moderated via the clutch actuation in the transmission 60. The mechanical power of the differential 62 can, in turn, be transmitted to the axle shafts 66, which are rotatably connected to the drive wheels 55.

[0012] A controller 112 may form part of a control system 114. As shown, the control system 114 receives information from sensors 116 and sends control signals to actuators 118. The sensors 116 may include, for example, sensors such as a battery state of charge sensor, a clutch position sensor, a speed sensor at the transmission input and / or output, and the like. As another example, the actuators 118 may include a shift fork actuator for the clutch, as well as an actuator for other transmission and broader vehicle components. The shift fork actuator may be configured to move the clutch 61 (e.g., a dog clutch or a synchronizer) into and out of engagement with one or more gears of the transmission 60. In other examples, the clutch may be a disconnect clutch.Controller 112 may receive input data from the sensors, process the input data via a processor, and trigger the actuators in response to the processed input data based on instructions programmed therein that correspond to one or more routines. In some examples, controller 112 may include instructions that send commands to actuator 63 to engage or disengage clutch 61. An input device 120 (e.g., gear selector, mode selector, accelerator pedal, brake pedal, combinations thereof, etc.) may provide input to controller 112 representing the driver's intent for vehicle control.

[0013] Fig. 1-8 contain a coordinate system for orienting the views. In one example, the y-axis can be a vertical axis (e.g., parallel to a gravity axis), the x-axis can be a longitudinal axis (e.g., a horizontal axis), and / or the z-axis can be a lateral axis. However, in other examples, the axes can have different orientations.

[0014] Fig. 2 shows a cross-sectional view of an example of a transmission 200 and a transmission system 201. The transmission 200 is an example of the transmission 60 of Fig. 1. Therefore, the components of the transmission 200 may also be included in the transmission 60 and vice versa. Furthermore, the transmission 200 may be incorporated in a vehicle such as the vehicle 50 of Fig. 1 must be included.

[0015] The transmission system 201 includes a shaft 202 with a gear 204 fixedly coupled thereto or formed therewith, a gear 206 freely mounted thereon, and a clutch 208 with a clutch arrangement 210. The clutch 208 is specifically illustrated as a dog clutch. However, in other examples, the clutch may have another suitable form. In another example, the clutch may be, for example, a synchronizer. In the illustrated example, the clutch 208 is arranged axially between the gear 204 and the gear 206. However, a variety of transmission designs with alternative arrangements of the gears and the clutch are contemplated.

[0016] The clutch 208 includes the clutch assembly 210 having a sleeve 212 that at least partially circumferentially surrounds a hub 214. The hub 214 includes a detent assembly 215 having openings 216 (e.g., through holes) in which balls 218 and springs 220 are disposed. Specifically, the springs 220 may be pre-compressed to exert a radially outward force on the balls 218. In this way, the sleeve 212 may be held in a desired position relative to the hub 214. Additionally, the springs 220 are illustrated as coil springs. However, in alternative examples, other types of springs, such as wave springs, may be used. The clutch assembly 210 is configured to engage and disengage depending on a position (e.g., an axial position) of the sleeve.

[0017] The detent assembly 215 is configured to hold the sleeve 212 and the hub 214 in a particular axial position with respect to the sleeve 212. More specifically, the detent assembly 215 is configured to hold the sleeve 212 in a neutral position in which the clutch is not engaged with a gear or other suitable component in the transmission 200. When the clutch 208 is switched between engagement and disengagement, the sleeve 212 translates axially with respect to the hub 214. The detent assembly 215 also includes a retaining device 217, which in the illustrated example is a retaining ring. However, in alternative examples, the retaining device may also be a bushing (e.g., an interference fit bushing) or other suitable device. The embodiment of the detent assembly with the bushing is described herein with reference to Fig. 8. The retaining device 217 holds the springs 220 and the balls 218 in the openings 216, thus reducing the risk of the balls and springs slipping during manufacture, thereby increasing the efficiency of the gearbox manufacturing process.

[0018] The transmission 200 includes gears that can mesh with upstream and / or downstream components. Specifically, the gear 204 can be coupled or formed with the shaft 202. The gear 204 can mesh with a gear 222. The gear 206 can be freely mounted on the shaft 202.

[0019] The clutch 208 is configured to be engaged and disengaged. Specifically, the clutch 208 may be configured to transfer mechanical power between the gear 204 and the gear 206 when engaged. In one example, the transmission may include two planetary gear units connected in series. The input of the transmission may be via the shaft 202, which, with the gear 204 (e.g., a pinion), forms the input of the first planetary gear unit (on the left side of the transmission in the Fig. 2). The output of the first planetary gear unit is its carrier, on which the hub of the clutch 214 is arranged. The clutch can receive the movement from the carrier of the first planetary gear unit and pass it on to the second planetary gear unit (on the right side of the transmission in the Fig. 2). When the clutch is shifted to the left, it can directly connect the carrier of the first planetary gear unit to the carrier of the second planetary gear unit (which in some cases acts as the output of the transmission). Consequently, the second planetary gear unit cannot operate as a reduction unit, but operates at a 1:1 ratio. When the clutch is engaged to the right, it can connect the carrier of the first planetary gear unit to the gear 206 of the second planetary gear unit. Consequently, the second planetary gear unit operates as a reduction unit. However, the clutch 208 can be configured to engage and disengage various gears or other suitable components of the transmission. In general, the clutch can be configured to allow or prevent the transfer of power between two components of the transmission system. For example, the clutch 208 canbe configured to engage gears to change the speed, or it may be configured with a disconnect function where, for example, the mechanical power at the output or input of the transmission is selectively interrupted.

[0020] An actuator 224 (e.g., a shift fork or other suitable actuating device) is configured to cause axial displacement of the sleeve 212 relative to the hub 214. Specifically, the actuator 224 may be a shift fork that engages an actuator interface 226 (e.g., shift fork interface) in the sleeve 212 to axially adjust the sleeve. The actuator 224 may be actuated hydraulically, mechanically, electrically, pneumatically, or combinations thereof.

[0021] Bearings 228 may be disposed between the hub 214 and the shaft 202. Thus, the hub 214 may be freely supported on the shaft 202. Furthermore, a bearing 230 may be coupled to the shaft 202. As described herein, a bearing supports the component to which it is attached, limits its movement, and allows its rotation. Thus, a bearing described herein may include an outer ring, an inner ring, and rolling elements (e.g., cylindrical rollers, balls, tapered rollers, needle rollers, and the like) disposed between the races.

[0022] A toothed interface 232 between the sleeve 212 and the hub 214 is in Fig. 2. The splined interface 232 includes splines in an inner diameter of the sleeve 212 and splines in an outer diameter of the hub 214. In this way, the hub and sleeve can move axially relative to each other while transmitting torque between them.

[0023] For reference, a rotation axis 250 of the shaft 202 is in Fig. 2. The section plane for the cross-sectional view from Fig. 2 passes through the rotation axis 250. The section plane AA' defines the cross-sectional view of Fig. 3. The rotary axis 250 is also in Fig. 3-8 is given as a reference where appropriate. The section plane for the cross-sectional view from Fig. 2 and Fig. 5, Fig. 7 and Fig. 8 passes through the rotation axis 250.

[0024] Fig. Figure 3 shows a cross-sectional view of the clutch assembly 210 with the hub 214, the sleeve 212, the detent assembly 215 and the shaft 202. The balls 218 and the springs 220 in the detent assembly 215 are in Fig. 3 along with the openings 216 in which the balls and springs come together. The hub may also include openings 300 that do not contain springs and balls. A tab 302 of the retaining ring 217 may be attached to one of the openings 300, restricting the movement of the retaining ring. In this way, the retaining ring can be held in a desired position. The openings 300 can enable more efficient manufacturing of the hub. Specifically, the openings 300 and the openings 216 can be arranged symmetrically about the axis 250. That is, in one specific example, the openings 216 with the springs 220 and the balls 218 therein can be spaced 120° apart. In this way, the central axes 350 of the opposing openings can be aligned so that the openings can be effectively machined or otherwise formed in the hub.Therefore, in such an example, the openings for the balls and springs, as well as the empty opening, can be manufactured or otherwise constructed more efficiently.

[0025] As shown, the retaining ring 217 is located between the shaft 202 and the hub 214 at the inner and outer diameters, respectively. As previously mentioned, one or more bearings (e.g., needle bearings) may be coupled to and disposed between the hub 214 and the shaft 202. A gap 304 may be formed between one end 306 of the retaining ring 217 and the retaining tab 302.

[0026] The splined interface 232 between the hub 214 and the sleeve 212 is also shown. The actuator interface 226 (e.g., shift fork interface) in the sleeve 212 is shown in Fig. 3. The actuator interface 226 includes a recess 227 contoured to engage with a shift fork or other suitable actuator.

[0027] Fig. Figure 4 shows another cross-sectional view of the clutch assembly 210 with the hub 214, the sleeve 212, and the detent assembly 215. The openings 216 with the balls 218 and the springs 220 positioned therein, the openings 300, and the retaining ring 217 in the detent assembly 215 are also shown. The actuator interface 226 in the sleeve 212 is shown in Fig. 4 further shown.

[0028] Fig. Figure 5 shows another cross-sectional view of the detent assembly 215. The openings 216 with the springs 220 and balls 218 positioned therein, the opening 300, and the retaining ring 217 are also shown. Furthermore, the hub 214 and the sleeve 212 are shown in Fig. 5. The balls 218 are connected to the detents 500. The springs 220, through their pre-compression, hold the balls in the sleeve detents. The hub 214 may include a retaining ring recess 502 into which at least a portion of the retaining ring can engage. The retaining ring recess may extend circumferentially around at least a portion of the inner diameter of the hub. In other examples, however, the hub's retaining ring recess may be omitted.

[0029] Fig. Figure 6 shows a detailed view of the detent assembly 215. The openings 216 are shown with lips 600 radially defining the balls 218. The lips may be mounted on an outer side of the hub 214. This allows the ball to move as desired during clutch operation. The lips allow efficient pre-assembly inside the hub without the sleeve, if desired. Therefore, the sleeve can be mounted later when it is more convenient for assembling the transmission. The lips can be created by machining the hole from the opposite side. Therefore, there may be holes without springs and balls. In addition, balls and springs can be mounted from the inside of the shaft and held in position by the retaining ring.

[0030] Fig. Figure 7 shows a further detailed view of the detent assembly 215. As shown, the balls 218 are connected to the detents 500 in the sleeve 212, and the springs 220, which may be preloaded, allow the balls to be held in engagement with the detents. Furthermore, the retaining ring 217 retains the springs 220 in the opening 216.

[0031] During assembly, the balls and springs can be inserted into the hub from the inside. A retaining ring or bushing can then be connected to the hub to hold the springs and balls in place. The sleeve can be added later during gearbox assembly.

[0032] Fig. Figure 8 shows another example of a detent assembly 800. The detent assembly 800 includes some components that overlap with the detent assembly 215 shown in Fig. 2-7, such as springs 802, balls 804, apertures 806, etc. A redundant description of the overlapping features, components, and the like is omitted for brevity. A bushing 808 is provided in the detent assembly 800 as a retaining device, in contrast to the retaining ring provided in Fig. 2-7. The socket 808 from Fig. 8 may be press-fitted to an inner diameter 810 of a hub 812. In this way, the springs 802 may be effectively retained in the openings 806. Specifically, the springs 802 may be compressed and retained in the opening 806, forcing the spring radially outward into a detent 814 in a sleeve 816. The sleeve allows the coupling assembly to be preassembled as a unit and then efficiently installed on a shaft, if desired.

[0033] Fig. 1-8 provide an installation method in which the detent assembly is installed on the shaft as an assembled unit. The technical effect of this installation method is to increase manufacturing efficiency. Fig. 1-8 also provide a method in which the clutch containing the detent assembly is adjusted (e.g., engaged and disengaged). The technical effect of these methods is to increase the manufacturing efficiency of the transmission in which the clutch is used, or to ensure reliable shifting between transmission modes.

[0034] Fig. Figures 2-8 are drawn approximately to scale, except for the schematically illustrated components. However, in other embodiments, the components may have different dimensions.

[0035] Fig.1-8 show example configurations with the relative arrangement of the various components. When these elements are in direct contact with each other or are directly coupled, they may be referred to as being in direct contact or directly coupled, respectively, at least in one example. Similarly, elements shown side by side or adjacent to each other may be adjacent to each other or adjacent to each other, at least in one example. For example, components that are in surface-to-surface contact with each other may be referred to as being in surface-to-surface contact. As another example, in at least one instance, elements that are separated from each other with only a space between them and that do not have any other components may be referred to as such.In yet another example, elements depicted above / below, on opposite sides, or to the left / right of each other may be referred to as such, relative to each other. Further, in at least one example, as depicted in the figures, a topmost element or point of an element may be referred to as a "top" of the component, and a bottommost element or point of the element may be referred to as a "bottom" of the component. As used herein, the terms top / bottom, upper / lower, above / below may refer to a vertical axis of the figures and may be used to describe the positioning of elements of the figures relative to each other. Thus, in one example, elements displayed above other elements are arranged vertically above the other elements.As another example, the shapes of the elements depicted in the figures may be referred to as such (e.g., circular, straight, flat, curved, rounded, beveled, angled, or the like). Furthermore, in at least one example, depicted elements that intersect each other may be referred to as intersecting elements or as intersecting elements. Furthermore, an element depicted inside another element or outside another element may be referred to as such.

[0036] The invention is further described in the following paragraphs. In one aspect, a coupling assembly is provided that includes a sleeve configured to at least partially circumferentially surround a hub; a detent assembly positioned in the hub that is configured to hold the sleeve and the hub in a defined axial position, and that includes: a first opening with a ball and a spring positioned therein; and a retainer that holds the spring and the ball in the first opening; wherein the ball engages a detent in the sleeve. Further, in one example, the retainer may also be a retaining ring. Furthermore, in one example, the retaining ring may include a tab configured to restrict rotation of the retaining ring. In another example, the tab may engage a second opening.In another example, the first opening may be a through-hole. In yet another example, the retainer may also be a bushing. In another example, the bushing may be press-fitted into the hub. In one example, the clutch assembly may be included in a jaw clutch. In another example, the sleeve may include a shift fork interface. In another example, the recess may include a lip radially confining the ball. In another example, the detent assembly may include a plurality of openings, each having a ball and a spring disposed therein. In yet another example, the plurality of openings may be arranged symmetrically about a central axis of the clutch assembly.

[0037] In another aspect, a method of operating a clutch is provided, comprising adjusting the clutch; wherein the clutch includes a clutch assembly comprising: a sleeve at least partially circumferentially surrounding a hub; a detent assembly positioned in the hub and configured to retain the sleeve and hub in a defined axial position, and including: an opening with a ball and a spring positioned therein; and a retainer retaining the spring in the openings; wherein the ball engages a detent in the sleeve. In one example, adjusting the clutch system may include sliding the hub into mating engagement with a gear.

[0038] In another aspect, a dog clutch assembly is provided that includes a sleeve at least partially circumferentially surrounding a hub; a detent assembly positioned in the hub and configured to retain the sleeve and hub in a defined axial position, and including: a first through-hole having a ball and a spring positioned therein; and a retaining ring or bushing retaining the spring in the first through-hole; wherein the ball engages a detent in the sleeve. In one example, the retaining ring may include a tab that engages a second through-hole and restricts rotation of the retaining ring, wherein the second through-hole does not include a ball or spring. In another example, the detent assembly may include second and third through-holes in which balls and springs are disposed.Furthermore, in another example, the first through-hole, the second through-hole, and the third through-hole may be successively spaced 120° apart from each other with respect to a central axis. Furthermore, in one example, the dog clutch assembly may be included in a transmission. Furthermore, in one example, the transmission may be an electric transmission.

[0039] The following claims particularly point out certain combinations and subcombinations that are considered novel and non-obvious. These claims may refer to "a" element or "a first" element, or the equivalent thereof. Such claims are to be construed as including the inclusion of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the present claims or by filing new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope than the original claims, are also to be considered included within the subject matter of the present disclosure.

Claims

[1] Coupling arrangement comprising: a sleeve configured to at least partially circumferentially surround a hub; and a detent arrangement arranged in the hub, which is configured to hold the sleeve and the hub in a defined axial position, and which includes: a first opening having a ball and a spring arranged therein; and a retaining device that holds the spring and the ball in the first opening; whereby the ball engages with a notch in the sleeve. [2] Coupling arrangement according to one of the preceding claims, wherein the holding device is a retaining ring. [3] The clutch assembly of claim 2, wherein the retaining ring includes a tab configured to restrict rotation of the retaining ring. [4] A coupling assembly according to claim 3, wherein the tab engages a second opening. [5] Coupling arrangement according to one of the preceding claims, wherein the first opening is a through hole. [6] Coupling arrangement according to one of the preceding claims, wherein the holding device is a bushing. [7] A clutch assembly according to claim 6, wherein the bushing is press-fitted into the hub. [8] Coupling arrangement according to one of the preceding claims, wherein the coupling arrangement is contained in a claw coupling. [9] A clutch assembly according to claim 8, wherein the sleeve includes a shift fork interface. [10] A coupling arrangement according to any one of the preceding claims, wherein the recess includes a lip which radially defines the ball. [11] A clutch assembly according to any preceding claim, wherein the detent assembly includes a plurality of apertures each containing a ball and a spring disposed therein. [12] The clutch assembly of claim 11, wherein the plurality of openings are arranged symmetrically to a central axis of the clutch assembly. [13] Coupling arrangement according to one of the preceding claims, wherein: the first opening is a first through hole, the detent arrangement includes a second and a third through-hole in which balls and springs are arranged; and / or the first through-hole, the second through-hole and the third through-hole are successively spaced by 120° with respect to a central axis. [14] Clutch arrangement according to one of the preceding claims, wherein the dog clutch arrangement is included in a transmission. [15] Clutch assembly according to claim 14, wherein the transmission is an electric transmission.

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