US-12624734-B2 - Shift system and method for power transmission assembly

Abstract

A method for power transmission method includes providing first and second shafts, a gear assembly having first and second gear ratios, and first and second coupling assemblies. The first coupling assembly enabling torque transfer from the first shaft to the second shaft, and the second coupling assembly enabling torque transfer from the first shaft to the second shaft. The speed of the first shaft varies, wherein the deployment of a locking element of the second coupling assembly is based on the speed of the first shaft.

Inventors

• Dustin Finn
• John Jennings

Assignees

• MEANS INDUSTRIES, INC.

Dates

Publication Date

20260512

Application Date

20250125

Claims (20)

1. 1 . A power transmission method comprising: providing a first shaft, the first shaft rotatable at a variable rotation speed; providing a second shaft, the second shaft rotatable at a variable rotation speed; providing a gear assembly between the first shaft and the second shaft, the gear assembly including at least a first gear ratio and a second gear ratio; providing a first coupling assembly enabling torque transfer from the first shaft to the second shaft through the first gear ratio, the first coupling assembly including a notch plate, a pocket plate, and a locking element in a deployed position; providing a second coupling assembly enabling torque transfer from the first shaft to the second shaft through the second gear ratio, the second coupling assembly including a notch plate, a pocket plate, and a locking element movable between a deployed and nondeployed position; and varying the speed of the first shaft in the same direction of rotation to select one of the first gear ratio and the second gear ratio, wherein deployment of the locking element of the second coupling assembly is based on the speed of the first shaft.
2. 2 . The power transmission method of claim 1 wherein: the step of varying the speed of the first shaft includes controlling the speed of the first shaft to engage the locking element of the second coupling assembly.
3. 3 . The power transmission method of claim 1 including the step of: transferring no torque through the first gear ratio when the locking element of the second coupling assembly is deployed.
4. 4 . The power transmission method of claim 1 including the step of: providing a third coupling assembly including a torque transmitting locking element; and deploying the torque transmitting locking element of the third coupling assembly and enabling torque from the first shaft to the second shaft in the first gear ratio or from the second shaft to the first shaft in the first gear ratio.
5. 5 . The power transmission method of claim 1 including the step of: providing a fourth coupling assembly including a torque transmitting locking element; and deploying the torque transmitting locking element of the fourth coupling assembly and enabling torque from the first shaft to the second shaft in the second gear ratio or from the second shaft to the first shaft in the second gear ratio.
6. 6 . The power transmission method of claim 1 wherein: the step of varying the speed of the first shaft includes reducing the speed of the first shaft until the speed of the first shaft synchronizes with the speed of the second gear ratio; and moving the locking element of the second coupling assembly to a deployed position after the speed of the first shaft synchronizes with the speed of the second gear ratio.
7. 7 . The power transmission method of claim 1 wherein: the step of varying the speed of the first shaft includes reducing the speed of the first shaft until the speed of the first shaft is below the speed of the second gear ratio; moving the locking element of the second coupling assembly to the deployed position; and increasing the speed of the first shaft to engage the locking element of the second coupling assembly.
8. 8 . The power transmission method of claim 1 including the step of: reducing the speed of the first shaft until the speed of the first shaft is below the speed of the second gear ratio to disengage the locking element of the second coupling assembly; moving the locking element of the second coupling assembly to the nondeployed position; and increasing the speed of the first shaft to engage the locking element of the first coupling assembly.
9. 9 . A power transmission method comprising: providing a first shaft, the first shaft rotatable at a variable rotation speed; providing a second shaft, the second shaft rotatable at a variable rotation speed; providing a gear assembly between the first shaft and the second shaft, the gear assembly including at least a first gear ratio and a second gear ratio; providing a first coupling assembly enabling torque transfer from the first shaft to the second shaft through the first gear ratio, the first coupling assembly including a notch plate, a pocket plate, and a locking element in a deployed position; providing a second coupling assembly enabling torque transfer from the first shaft to the second shaft through the second gear ratio, the second coupling assembly including a notch plate, a pocket plate, and a locking element movable between a deployed and nondeployed position; varying the speed of the first shaft to select one of the first gear ratio and the second gear ratio, wherein deployment of the locking element of the second coupling assembly is based on the speed of the first shaft; the step of varying the speed of the first shaft includes reducing the speed of the first shaft until the speed of the first shaft synchronizes with the speed of the second gear ratio; and moving the locking element of the second coupling assembly to a deployed position after the speed of the first shaft synchronizes with the speed of the second gear ratio.
10. 10 . A power transmission method comprising: providing a first shaft, the first shaft rotatable at a variable rotation speed; providing a second shaft, the second shaft rotatable at a variable rotation speed; providing a gear assembly between the first shaft and the second shaft, the gear assembly including at least a first gear ratio and a second gear ratio; providing a first coupling assembly enabling torque transfer from the first shaft to the second shaft through the first gear ratio, the first coupling assembly including a notch plate, a pocket plate, and a locking element in a deployed position; providing a second coupling assembly enabling torque transfer from the first shaft to the second shaft through the second gear ratio, the second coupling assembly including a notch plate, a pocket plate, and a locking element movable between a deployed and nondeployed position; varying the speed of the first shaft to select one of the first gear ratio and the second gear ratio, wherein deployment of the locking element of the second coupling assembly is based on the speed of the first shaft; and the step of varying the speed of the first shaft includes reducing the speed of the first shaft until the speed of the first shaft is below the speed of the second gear ratio and increasing the speed of the first shaft to engage the locking element of the second coupling assembly.
11. 11 . The power transmission method of claim 10 wherein: the step of reducing the speed of the first shaft until the speed of the first shaft is below the speed of the second gear ratio disengages the locking element of the second coupling assembly.
12. 12 . A power transmission method comprising: providing a first shaft, the first shaft rotatable at a variable rotation speed; providing a second shaft, the second shaft rotatable at a variable rotation speed; providing a gear assembly, the gear assembly including at least a first gear ratio and a second gear ratio; providing a first one-way clutch including a forward torque transmitting locking element; providing a second one-way clutch including a forward torque transmitting locking element; deploying the forward torque transmitting locking element of the first one-way clutch and enabling torque from the first shaft to the second shaft in the first gear ratio; reducing the speed of the first shaft until the speed of the first shaft synchronizes with the speed of the second gear ratio; and deploying the forward torque transmitting locking element of the second one-way clutch after the speed of the first shaft synchronizes with the speed of the second gear ratio and enabling torque from the first shaft to the second shaft in the second gear ratio.
13. 13 . The power transmission method of claim 12 including the step of: providing a third one-way clutch including a reverse torque transmitting locking element; and deploying the reverse torque transmitting locking element of the third one-way clutch and enabling torque from the first shaft to the second shaft in the first gear ratio.
14. 14 . The power transmission method of claim 13 including the step of: providing a fourth one-way clutch including a reverse torque transmitting locking element; and deploying the reverse torque transmitting locking element of the fourth one-way clutch and enabling torque from the first shaft to the second shaft in the second gear ratio.
15. 15 . The power transmission method of claim 12 including the step of: increasing the speed of the first shaft to engage the forward torque transmitting locking element of one of the first one-way clutch and the second one-way clutch.
16. 16 . The power transmission method of claim 12 including the step of: enabling no torque in the first gear ratio when the forward torque transmitting locking element of the second one-way clutch is deployed.
17. 17 . The power transmission method of claim 12 including the step of: providing a one-way clutch including a regeneration torque transmitting locking element; and deploying the regeneration torque transmitting locking element of the one-way clutch and enabling torque from the second shaft to the first shaft in the first gear ratio.
18. 18 . The power transmission method of claim 12 including the step of: providing a one-way clutch including a regeneration torque transmitting locking element; and deploying the regeneration torque transmitting locking element of the one-way clutch and enabling torque from the second shaft to the first shaft in the second gear ratio.
19. 19 . A power transmission method comprising: providing a first shaft, the first shaft rotatable at a variable rotation speed; providing a second shaft, the second shaft rotatable at a variable rotation speed; providing a gear assembly, the gear assembly including at least a first gear ratio and a second gear ratio; providing a first one-way clutch including a forward torque transmitting locking element, the first one-way clutch associated with the first gear ratio; providing a second one-way clutch including a forward torque transmitting locking element, the second one-way clutch associated with the second gear ratio; enabling torque from the first shaft to the second shaft through the second gear ratio with the forward torque transmitting locking element of the second one-way clutch in a deployed position; moving the forward torque transmitting locking element of the second one-way clutch in a nondeployed position; after the forward torque transmitting locking element of the second one-way clutch is in a nondeployed position, changing the rotation speed of the first shaft to engage the forward torque transmitting locking element of the first one-way clutch; and enabling torque from the first shaft to the second shaft through the first gear ratio.
20. 20 . The power transmission method of claim 19 including the step of: reducing the speed of the first shaft below the speed of the second gear ratio wherein the forward torque transmitting locking element of the second one-way clutch moves to the nondeployed position.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 18/674,857 filed on May 25, 2024, which claims the benefit of U.S. Provisional Application No. 63/468,586, filed May 24, 2023. The disclosure of the above application(s) are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention generally relates to a vehicle power train; and, more specifically, a power train using a shift system including a one-way clutch. 2. Description of Related Art In the field of automotive technology, vehicle powertrains typically include shift systems using multiple friction clutch elements. Automatic transmissions (AT) use wet friction clutches, dual-clutch transmissions (DCT) use wet & dry friction clutches, and manual transmission (MT) and automated manual transmissions (AMT) use synchronizers, friction cone clutches, and a shift collar. Other shift mechanisms use various elements of the above or in combination with a mechanical dog clutch, shift collar, or sliding sleeve. Friction clutches add drag, reduce efficiency, and reduce electric vehicle range. They also create heat, wear, and contamination that can lead to other failure modes. Friction clutches require hydraulics, fluids, pumps, and hydraulic distribution. This adds weight, complexity, possibility of leaks and generates heat. Elimination of friction clutches also addresses an industry need to support sustainability and circular economy objectives and targets. Friction clutches wear, need replacing, and cannot be reused, repurposed, or easily recycled. Additionally, friction clutch inefficiencies constitute a significant source of heat generation. Battery electric vehicle drive systems include thermal management issues related to heat generation. Existing powertrains often use electric motors and controllable or selectable coupling assemblies, such as one-way clutches. These coupling assemblies can be electromagnetically operated and magnetically controlled. Various types of selectable one-way clutches, including those using a selector plate, a solenoid, and a linear actuator, are known. The foregoing are examples of one-way clutches that may be used in the clutch system disclosed herein. SUMMARY OF THE INVENTION A method for power transmission includes providing a first shaft, the first shaft rotatable at a variable rotation speed, a second shaft, the second shaft rotatable at a variable rotation speed, a gear assembly between the first shaft and the second shaft, the gear assembly including at least a first gear ratio and a second gear ratio. The method also includes providing a first coupling assembly enabling torque transfer from the first shaft to the second shaft, the first coupling assembly including a notch plate, a pocket plate, and a locking element in a deployed position, and a second coupling assembly enabling torque transfer from the first shaft to the second shaft, the second coupling assembly including a notch plate, a pocket plate, and a locking element movable between a deployed and nondeployed position. The speed of the first shaft varies, wherein the deployment of a locking element of the second coupling assembly is based on the speed of the first shaft. Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: FIG. 1 is a schematic illustration and overview of a multi-speed transmission, including a shift system according to one example of the power transmission system of the present invention. FIG. 2 is a schematic cross-sectional view illustrating one example of a shift system and mechanism for use with the power transmission system of FIG. 1, including an actuator in one position. FIGS. 2A and 2B are exploded, cross-sectional views illustrating locking element positions for the actuator position of FIG. 2. FIG. 3 is a schematic cross-sectional view illustrating one example of the shift system for use with the power transmission system of FIG. 1, including an actuator in another position. FIGS. 3A and 3B are exploded, cross-sectional views illustrating locking element positions for the actuator position of FIG. 3. FIG. 4 is a schematic cross-sectional view illustrating the shift system for use with the power transmission system of FIG. 1, including the actuator in yet another position. FIGS. 4A and 4B are exploded, cross-sectional views illustrating locking element positions for the actuator position of FIG. 4. FIG. 5 is a flowchart of an example of a method of operation of a shif