US 12,031,628 B1Granted

Gearboxes for electric vehicle drivetrains and methods of shifting thereof

AssigneeDIMAAG-AI, Inc.

InventorsIan Wright, David Kieke

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Abstract

Described herein is a gearbox for an electric vehicle drivetrain unit comprising a gearbox enclosure, a support rod, a first piston, a second piston, and various hydraulic fluid passages. The support rod extends into the gearbox enclosure and at least partially protrudes/extends into the first and second pistons. The first piston, second piston, and support rod are fluidically connected with the hydraulic fluid passages such that when the gearbox is in a neutral gear, pressurized hydraulic fluid forces the first piston and the second piston against the support rod. When the gearbox is in a first gear, pressurized hydraulic fluid forces the support rod against the gearbox enclosure either directly or through the first piston. When the gearbox is in a second gear, pressurized hydraulic fluid forces the support rod against the gearbox enclosure directly or through the second piston. Also described are electric vehicles and shifting methods.

Claims20

Dependent claims

A gearbox for an electric vehicle drivetrain unit, the gearbox comprising:

a gearbox enclosure comprising a first-piston enclosure limiter, a second-piston enclosure limiter, a second neutral-gear passage, a first neutral-gear passage, a first-gear passage, and a second-gear passage;
a support rod extending into the gearbox enclosure and fluidically coupled to at least the first-gear passage and the second-gear passage;
a first piston positioned between and slidably isolating the second neutral-gear passage from at least a first portion of the support rod;
and
a second piston positioned between and slidably isolating the first neutral-gear passage from at least a second portion of the support rod,
a shift-fork support positioned on and connected to the support rod, wherein:
when the gearbox is in a neutral gear, a hydraulic fluid is configured to pressurize the second neutral-gear passage and the first neutral-gear passage forcing the first piston against the first-piston enclosure limiter and the support rod and also forcing the second piston against the second-piston enclosure limiter and the support rod,
when the gearbox is in a first gear, the hydraulic fluid is configured to pressurize the first-gear passage and the first neutral-gear passage, forcing the support rod against the gearbox enclosure either directly or through the first piston and the second piston against the second-piston enclosure limiter, and
when the gearbox is in a second gear, the hydraulic fluid is configured to pressurize the second-gear passage and the second neutral-gear passage forcing the support rod against the gearbox enclosure through the second piston and the first piston against the first-piston enclosure limiter.

6 more elements

An electric vehicle drivetrain unit comprising:

an electric motor;
a hydraulic tank and a hydraulic pump;
a gearbox coupled to the motor;
a wheel coupled to the gearbox, wherein:
the gearbox comprises a gearbox enclosure and a support rod extending into the gearbox enclosure and fluidically coupled to a second neutral-gear passage, a first-gear passage, a second-gear passage, a first neutral-gear passage, a first-piston enclosure limiter, a second-piston enclosure limiter, a shift-fork support slidably coupled to the support rod, a first piston positioned between and slidably isolating first the neutral-gear passage from at least a first portion of the support rod, and a second piston positioned between and slidably isolating the first neutral-gear passage from at least a second portion of the support rod;
when the gearbox is in a neutral gear, a hydraulic fluid is configured to pressurize the second neutral-gear passage and the first neutral-gear passage forcing the first piston against the first-piston enclosure limiter and the support rod and also forcing the second piston against the second-piston enclosure limiter and the support rod;
when the gearbox is in a first gear, the hydraulic fluid is configured to pressurize the first-gear passage and the first neutral-gear passage, forcing the support rod against the gearbox enclosure either directly or through the first piston and the second piston against the second-piston enclosure limiter;
and
when the gearbox is in a second gear, the hydraulic fluid is configured to pressurize the second-gear passage and the second neutral-gear passage forcing the support rod against the gearbox enclosure through the second piston and the first piston against the first-piston enclosure limiter.

6 more elements

A method of shifting gears in an electric vehicle comprising a gearbox and a drivetrain controller, the method comprising:

providing the gearbox comprising a gear position sensor, a first neutral-gear valve, a second neutral-gear valve, a first-gear valve, a second-gear valve, a drivetrain controller communicatively connected with the gear position sensor and the valves, a gearbox enclosure comprising a first-piston enclosure limiter, a second-piston enclosure limiter, a second neutral-gear passage, a first neutral-gear passage, a first-gear passage, a second-gear passage, a support rod extending into the gearbox enclosure and fluidically coupled to at least the first-gear passage and the second-gear passage, a first piston positioned between and slidably isolating the second neutral-gear passage from at least a first portion of the support rod, and a second piston positioned between and slidably isolating the first neutral-gear passage from at least a second portion of the support rod comprising a first neutral-gear valve, a second neutral-gear valve, a first-gear valve, and a second-gear valve;
detecting by the gear position sensor a current gear input;
receiving at the drivetrain controller a current gear input;
receiving at the drivetrain controller a gear input;
comparing by the drivetrain controller the current gear input and the gear input;
determining by the drivetrain controller a new valve configuration if the current gear input and the gear input are different;
and
activating by the drivetrain controller the first neutral-gear valve, the second neutral-gear valve, the first-gear valve, and the second-gear valve such that the valves are configured to the new valve configuration if the current gear input and gear input are different, wherein:
when the gearbox is in a neutral gear, a hydraulic fluid is configured to pressurize the second neutral-gear passage and the first neutral-gear passage forcing the first piston against the first-piston enclosure limiter and the support rod and also forcing the second piston against the second-piston enclosure limiter and the support rod,
when the gearbox is in a first gear, the hydraulic fluid is configured to pressurize the first-gear passage and the first neutral-gear passage, forcing the support rod against the gearbox enclosure either directly or through the first piston and the second piston against the second-piston enclosure limiter, and
when the gearbox is in a second gear, the hydraulic fluid is configured to pressurize the second-gear passage and the second first-neutral-gear passage forcing the support rod against the gearbox enclosure through the second piston and the first piston against the first-piston enclosure limiter.

8 more elements

Dependencies are inferred from the claim text.