TRANSMISSION FOR A HYBRID POWERTRAIN

Abstract

Transmission (28), comprising: a first entrance (34); a second entrance (36); a third entrance (38); an output (40); a sun gear (42) connected to the first input (34) and rotatable; a carrier (44) attached to and rotatable with the third input (38), the carrier (44) rotatably supporting a plurality of pinions (46), each of the plurality of pinions (46) including a first pinion gear (48) and a second pinion gear (50) operatively connected for common rotation; wherein every second pinion gear (50) of the plurality of pinions (46) is arranged in toothed engagement with the sun gear (42); a first ring gear (56) arranged in toothed engagement with each first pinion gear (48) of each of the plurality of pinions (46) and arranged in torque connection with the second input (36); a second ring gear (60) arranged in toothed engagement with each second pinion gear (50) of each of the plurality of pinions (46) and arranged in torque connection with the output (40); characterized in that the transmission (28) further comprises a first transfer gear (58) arranged in meshing engagement with the first ring gear (56) and the second input (36), and a transfer gear set (62) interconnecting the second ring gear (60) and the output (40); wherein the transfer gear set (62) includes a countershaft (64) carrying a second transfer gear (66) and a third transfer gear (68); wherein the second distributor gear (66) and the third distributor gear (68) are fixed to the countershaft (64) and are rotatable therewith, whereas the first distributor gear (58) is rotatably mounted on the countershaft (64) by means of at least one bearing.

Description

INITIATIONThe present invention relates generally to a transmission according to the preamble of claim 1 for a hybrid drive train, as is known in the art essentially from US 2003 / 0 224 892 A1.A similar transmission is also disclosed in DE 11 2013 007 070 T5.A hybrid powertrain may include a first electrical device, a second electrical device, and an engine. The prime mover may include, but is not limited to, an internal combustion engine. A transmission selectively receives torque from each of the first electrical device, the second electrical device, and the prime mover and transmits the torque to a final drive.The invention is based on the object of providing an improved power flow between the individual inputs and the output in a hybrid transmission of the generic type.SUMMARYThis object is achieved according to the invention with a transmission which is distinguished by the features of claim 1.The transmission includes a first input, a second input, a third input, and an output. A sun gear is connected to and rotatable with the first input. A carrier is mounted on and rotatable with the third input. The carrier rotatably supports a plurality of pinions. Each of the plurality of sprockets includes a first sprocket and a second sprocket fixed together for common rotation. Each second pinion gear of the plurality of pinions is disposed in meshing engagement with the sun gear. A first ring gear is disposed in meshing engagement with each first pinion gear of each of the plurality of pinions. The first ring gear is disposed in torque communication with the second input. A second ring gear is disposed in meshing engagement with each second pinion gear of each of the plurality of pinions. The second ring gear is disposed in torque communication with the output. A first transfer gear is disposed in meshing engagement with the first ring gear and the second input. A transfer gear set connects the second ring gear and the output. The transfer gear set includes a countershaft that supports a second transfer gear and a third transfer gear. The second distributor gearwheel and the third distributor gearwheel are mounted on the countershaft and are rotatable therewith, whereas the first distributor gearwheel is rotatably mounted on the countershaft by means of at least one bearing.The third transfer gear may be disposed in meshing engagement with the second ring gear.In another aspect of the transmission, the transfer gear set includes a final drive gear coupled to the output. The second transfer gear is disposed in meshing engagement with the final drive gear.In another aspect of the transmission, an input brake is coupled to the third input and is operable to resist rotation of the third input. In one embodiment, the first input defines a hollow interior, and the input brake includes a brake shaft attached to the third input and disposed radially inward of the hollow interior of the first input.In another aspect of the transmission, the first input is mounted to a first electrical device and operable to receive torque from the first electrical device. The second input is attached to a second electrical device and is operable to receive torque from the second electrical device. The third input is mounted on an engine and may receive torque from the engine. The output is attached to a final drive and operable to transmit torque to the final drive.A drive train is also provided. The powertrain includes a first electrical device, a second electrical device, an engine, and a transmission. The transmission is coupled to the first electrical device, the second electrical device, of the prime mover. The transmission is operable to transfer torque from the first electrical device, the second electrical device, and the prime mover to a final drive. The transmission includes a first input mounted to the first electrical device. The first input is operable to receive torque from the first electrical device. A second input is attached to the second electrical device. The second input is operable to receive torque from the second electrical device. A third input is mounted on the prime mover. The third input is operable to receive torque from the prime mover. An output is connected to the final drive. The output is operable to transmit torque to the final drive. A sun gear is connected to and rotatable with the first input. A carrier is mounted on and rotatable with the third input. The carrier rotatably supports a plurality of pinions. Each of the plurality of sprockets includes a first sprocket and a second sprocket. Each second pinion gear of the plurality of pinions is disposed in meshing engagement with the sun gear. A first ring gear is disposed in meshing engagement with each first pinion gear of each of the plurality of pinion gears. The first ring gear is disposed in torque communication with the second input. A second ring gear is disposed in meshing engagement with each second pinion gear of each of the plurality of pinions. The second ring gear is disposed in torque communication with the output.In one aspect of the powertrain, a first transfer gear is disposed in meshing engagement with the first ring gear and the second input.In another aspect of the powertrain, a transfer gearset connects the second ring gear and the output. The transfer gear set includes a countershaft that supports a second transfer gear and a third transfer gear. The second transfer gear and the third transfer gear are mounted on the countershaft and are rotatable therewith. The third transfer gear is disposed in meshing engagement with the second ring gear.In another aspect of the powertrain, the transfer gear set includes a final drive gear coupled to the output. The second transfer gear is disposed in meshing engagement with the final drive gear.In another aspect of the powertrain, an input brake is coupled to the third input. The input brake is operable to resist rotation of the third input.The above features and advantages, as well as other features and advantages of the present teachings, can be readily derived from the following detailed description of the best modes for carrying out the teachings when considered in connection with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a schematic illustration of a powertrain in dash lines. FIG. 2 is a schematic cross-sectional view of the powertrain.DETAILED DESCRIPTIONIn the FIGS., where the components are shown numbered in multiple views, 20 is generally a powertrain. The powertrain 20 may be integrated with any movable platform, such as a car, truck, boat, ATV, motorcycle, tractor, etc.The powertrain 20 includes a first electrical device 22, a second electrical device 24, an engine 26, a transmission 28, and a final drive 30. the first electrical device 22 and the second electrical device 24 may include a device capable of converting electrical energy into torque and / or rotation of a shaft. For example, the first electrical device 22 and the second electrical device 24 may include, but are not limited to, an electric motor or an electric motor / generator. It should be appreciated that the first electrical device 22 and the second electrical device 24 may include another device not specifically mentioned or described herein. The specific type and configuration of the first electrical device 22 and the second electrical device 24 are not relevant to the teachings of the invention and are therefore not described in detail herein.The prime mover 26 may include any device or system that serves to generate torque and / or rotate a shaft. The engine 26 may include an internal combustion engine such as, but not limited to, a gasoline engine or a diesel engine. It should be appreciated that the prime mover 26 may include another device not specifically mentioned or described herein. The specific type and configuration of the prime mover 26 are not relevant to the teachings of the invention and therefore will not be described in detail herein.The transmission 28 is coupled to the first electrical device 22, the second electrical device 24, the prime mover 26, and is operable to transmit torque from the first electrical device 22, the second electrical device 24, and the prime mover 26 to the final drive 30. The final drive 30 transfers torque between the transmission 28 and a drive device. The drive device may include, but is not limited to, a wheel, a track, a propeller, etc. The final drive 30 may include an axle shaft, differential gear, propeller shaft, one or more wheels, etc. The specific configuration and components of the final drive 30 are not relevant to the teachings of this invention and therefore will not be described in detail herein.The transmission 28 includes a housing 32 that supports the components of the transmission 28. The housing 32 may additionally support the first electrical device 22 and / or the second electrical device 24. The transmission 28 further includes a first input 34, a second input 36, a third input 38, and an output 40. the first input 34 is mounted to a first electrical device 22 and is operable to receive torque from the first electrical device 22. The first input 34 may include, but is not limited to, a shaft or other similar structure capable of transmitting torque and / or rotation between the first electrical device 22 and the transmission 28. The first input 34 is rotatably supported by the housing 32. Thus, one or more bearings may connect the first input 34 and the housing 32 together.The second input 36 is attached to a second electrical device 24 and is operable to receive torque from the second electrical device 24. The second input 36 may include, but is not limited to, a shaft or other similar structure capable of transmitting torque and / or rotation between the second electrical device 24 and the transmission 28. The second input 36 is rotatably supported by the housing 32. Thus, one or more bearings may connect the second input 36 and the housing 32 together.The third input 38 is mounted to an engine 26 and operable to receive torque from the engine 26. The third input 38 may include a shaft or other similar structure capable of transmitting torque and / or rotation between the engine 26 and the transmission 28. The third input 38 is rotatably supported by the housing 32. Thus, one or more bearings may connect the third input 38 and the housing 32 together.The output 40 is mounted on a final drive 30 and is operable to transmit torque to the final drive 30. The output 40 may include, but is not limited to, a shaft or other similar structure capable of transmitting torque and / or rotation between the transmission 28 and the final drive 30. The output 40 is rotatably supported by the housing 32. Thus, one or more bearings may connect the outlet 40 and the housing 32 together.A sun gear 42 is connected to and rotatable with the first input 34. Similarly, it should also be appreciated that the torque applied to the sun gear 42 is transmitted to the first electrical device 22 via the first input 34.A carrier 44 is mounted on and rotatable with the third input 38. Accordingly, it should be appreciated that the prime mover 26 applies torque to the third input 38 which, in turn, applies torque to the carrier 44. Similarly, it should be appreciated that the torque applied to the carrier 44 is transmitted to the prime mover 26 via the third input 38. As shown in FIG. 2, the carrier 44 may rotatably support a plurality of pinions 46. Each of the pinions 46 includes a first pinion gear 48 and a second pinion gear 50 fixed together for common rotation. Accordingly, each adjacent pair of pinion gears 46, including a first pinion gear 48 and a second pinion gear 50, rotates together with their respective pinion gear 46. Each adjacent pair of pinion gears, including a first pinion gear 48 and a second pinion gear 50, may be integrally formed as a single component or may be formed as individual parts and connected in a manner that allows the first pinion gear 48 and the second pinion gear 50 to rotate together. As shown in FIG. 2, the first pinion gear 48 includes a first diameter 52 and the second pinion gear 50 includes a second diameter 54. the first diameter 52 of the first pinion gear 48 is greater than the second diameter 54 of the second pinion gear 50, thereby forming a stepped pinion gear 46 arrangement. Each second pinion gear 50 of each of the pinions 46 is disposed in meshing engagement with the sun gear 42 to transfer torque and rotation between the pinions 46 and the sun gear 42.A first ring gear 56 is disposed in meshing engagement with each first pinion gear 48 of each of the pinions 46. The first ring gear 56 is disposed in torque communication with the second input 36. More specifically, a first transfer gear 58 is in meshing engagement with the first ring gear and the second input 36 to transfer torque and rotation between the second input 36 and the first ring gear 56. Similarly, it should also be appreciated that the second electrical device 24 applies torque to the second input 36, which in turn applies torque to the first transfer gear 58, which in turn applies torque to the first ring gear 56. Similarly, it will be further understood that torque applied to the carrier 44 may be transmitted to the second electrical device 24 through the first pinion gears 48, the first transfer gear 58, and the second input 36.A second ring gear 60 is disposed in meshing engagement with each second pinion gear 50 of each of the pinion gears 46. The second ring gear 60 is disposed in torque communication with the output 40. Specifically, the transmission 28 includes a transfer gear set 62 that connects the second ring gear 60 and the output 40. Transfer gear set 62 includes a countershaft 64 that supports a second transfer gear 66 and a third transfer gear 68. The second transfer gear 66 and the third transfer gear 68 are mounted on and rotatable with the countershaft 64. The countershaft 64 rotatably supports the first transfer gear 58. The housing 32 rotatably supports the countershaft 64. The third transfer gear 68 is disposed in meshing engagement with the second ring gear 60. The transfer gear set 62 further includes a final drive gear 72 that interconnects the output 40 and the second transfer gear 66. As shown in FIG. 2, the final drive gear 72 is coupled to the output 40. The second transfer gear 66 is disposed in meshing engagement with the final drive gear 72. It should be appreciated that since both the second transfer gear 66 and the third transfer gear 68 are rotatable with the countershaft 64, rotation of the third transfer gear 68 also rotates the second transfer gear 66. The rotation and / or torque applied to the final drive gear 72 is transmitted to the output 40.Referring to FIG. 2, the transmission 28 may further include an input brake 76. In the exemplary embodiment shown, the input brake 76 is coupled to the third input 38. The input brake 76 is operable to resist rotation of the third input 38. For example, the input brake 76 may selectively connect the third input 38 to the housing 32 to resist or prevent rotation of the third input 38. In the exemplary embodiment shown, the first input 34 defines a hollow interior 78; the input brake 76 includes a brake shaft 80 attached to the third input 38 through the hollow interior 78 of the first input 34. The brake shaft 80 is disposed radially inward of the hollow interior 78 of the first input 34. Thus, the brake shaft 80 and the first input 34 are coaxially aligned and rotatable about a common axis of rotation. The input brake 76 may include, but is not limited to, a brake or clutch that connects the brake shaft 80 and the housing 32 together. In addition, the brake shaft 80 may be rotatably supported by the housing 32. Thus, one or more bearings may connect the brake shaft 80 and the housing 32 together. The specific configuration and operation of the input brake 76 is not relevant to the teachings of this invention and will therefore not be described in detail herein.

Claims

A transmission (28) comprising: a first input (34); a second input (36); a third input (38); an output (40); a sun gear (42) connected to and rotatable with the first input (34); a carrier (44) attached to and rotatable with the third input (38), the carrier (44) rotatably supporting a plurality of pinions (46), each of the plurality of pinions (46) including a first pinion gear (48) and a second pinion gear (50) operatively connected for common rotation; each second pinion gear (50) of the plurality of pinions (46) being disposed in meshing engagement with the sun gear (42); a first ring gear (56) disposed in meshing engagement with each first pinion gear (48) of each of the plurality of pinions (46) and disposed in torque communication with the second input (36); a second ring gear (60) disposed in meshing engagement with each second pinion gear (50) of each of the plurality of pinions (46) and disposed in torque communication with the output (40); characterized in that the transmission (28) further comprises a first transfer gear (58) disposed in meshing engagement with the first ring gear (56) and the second input (36) and a transfer gear set (62) interconnecting the second ring gear (60) and the output (40); the transfer gear set (62) having a countershaft (64) carrying a second transfer gear (66) and a third transfer gear (68); wherein the second distributor gearwheel (66) and the third distributor gearwheel (68) are fastened to the countershaft (64) and are rotatable therewith, whereas the first distributor gearwheel (58) is rotatably mounted on the countershaft (64) by means of at least one bearing.The transmission (28) of claim 1, wherein the third transfer gear (68) is disposed in meshing engagement with the second ring gear (60).The transmission (28) of claim 2, wherein the transfer gear set (62) includes a final drive gear (72) coupled to and rotatable with the output (40).The transmission (28) of claim 3, wherein the second transfer gear (66) is disposed in meshing engagement with the final drive gear (72).The transmission (28) of claim 1, further comprising an input brake (76) coupled to the third input (38) and operable to resist rotation of the third input (38).The transmission (28) of claim 5, wherein the first input (34) defines a hollow interior (78), and wherein the input brake (76) includes a brake shaft (80) attached to the third input (38) and disposed radially within the hollow interior (78) of the first input (34).

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