Hydraulic transaxle

Patent metadata

Field	Value
Publication number	US-10865872-B2
Application number	US-201916394939-A
Country	US
Kind code	B2
Filing date	Apr 25, 2019
Priority date	Jul 5, 2013
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

A hydraulic transaxle includes a transaxle casing including an upper transaxle housing and a lower casing, hydrostatic transmission (“HST”), and an axle. The HST has a hydraulic pump and a hydraulic motor that are fluidly connected to each other. The hydraulic motor has a motor shaft that is drivingly connected to the axle through a reduction gear train that is disposed between the hydraulic pump and the axle. Reduction gear train has a gear shaft supported by the upper transaxle housing via a ball bearing. At least a part of the upper transaxle housing is formed by a gear top cover made of metal and covering the reduction gear train. Ball bearing is supported by the upper transaxle housing and the gear top cover.

First claim

What is claimed is:

1. A transaxle comprising:
a transaxle casing configured to be splittable into an upper casing and a lower casing;
a hydrostatic transmission disposed in the transaxle casing; and
an axle that is disposed in the transaxle casing and driven by the hydrostatic transmission,
wherein the hydrostatic transmission includes a hydraulic pump and a hydraulic motor fluidly connected to each other,
wherein the hydraulic pump has a pump shaft extending perpendicularly to the axle,
wherein the hydraulic motor has a motor shaft that is drivingly connected to the axle through a reduction gear train that is disposed between the hydraulic pump and the axle,
wherein the reduction gear train has a parallel axis with regard to the axle, and has a gear shaft supported by the upper casing via a bearing,
wherein the motor shaft has an axis extending at an angle to an axis of the pump shaft,
wherein at least a part of the upper casing is formed by a top cover made of metal and covering the reduction gear train, and
wherein the bearing is supported by the upper casing and the top cover.

2. The transaxle according to claim 1 , further comprising a fluid inspection rod detachably attached to the top cover, wherein the fluid inspection rod is inserted into the transaxle casing.

3. The transaxle according to claim 1 , wherein the top cover is provided with a breather disposed at a top portion of the transaxle casing, and wherein the breather has a rib projecting to surround a side periphery of the breather.

4. The transaxle according to claim 1 , wherein the top cover has a heat radiation fin projecting from an outer surface.

5. The transaxle according to claim 1 , wherein a boundary between the top cover and the lower casing is sealed with liquid packing.

Assignees

• Kanzaki Kokyukoki Mfg Co Ltd

Inventors

• Sugimoto Hiroshi
• Ota Takehiro
• Yasuda Toshifumi

Classifications

• B60Y2200/223

  Ridable lawn mowers · CPC title

• B60K17/105 Primary

  Units comprising at least a part of the gearing and a torque-transmitting axle, e.g. transaxles (B60K17/14 takes precedence) · CPC title

• F16H61/4174

  Control of venting, e.g. removing trapped air · CPC title

• B60K2025/065

  the transmission being fluidic, e.g. hydraulic · CPC title

• B60K17/14

  the motor of fluid or electric gearing being disposed in, or adjacent to, traction wheel · CPC title