Hydraulic motor with axial pistons

Abstract

A hydraulic motor (1) with axial pistons, comprising a casing (2) for containing a motor shaft (4) and a plurality of pistons (5) which are substantially parallel to the motor shaft and act on a swash plate (6) which is mounted around the motor shaft (4) so as to oscillate between a maximum- displacement configuration and a minimum-displacement configuration, at least one first duct (8) and one second duct (9) for connecting the pistons (5) to a circuit for supplying a working fluid, and hydraulic means (13) for varying the inclination of the swash plate (6) as a function of the higher pressure of the working fluid in the connecting ducts (8, 9). The hydraulic motor (1) is provided with valve means (14) for enabling and disabling the hydraulic means (13), which can be moved functionally between a first working position, in which the hydraulic means (13) are disabled and the swash plate (6) is arranged in the maximum-displacement configuration, and a second working position, in which the hydraulic means (13) are enabled and the swash plate (6) is arranged in any angular configuration, comprised between the maximum- and minimum-displacement configurations, of equilibrium for the higher applied pressure, the swash plate (6) oscillating continuously and bidirectionally between the maximum- and minimum- displacement configurations.

Description

technical field [0001] The present invention relates to a hydraulic motor with an axial piston, and more particularly to a wheel drive for driving crawlers of small excavators and the like. Background technique [0002] As we all know, large or small excavators are widely used in the field of construction to dig up, lift and transport materials such as earth, sand, gravel and the like. [0003] Smaller excavators with a general size between 1 and 6 tons are often called mini excavators and are used for various operations in confined yards with limited operating space due to their small size. [0004] Conventional mini excavators are provided with track drives actuated by hydraulic wheel drives. [0005] These wheel drives consist of a hydraulic motor, usually of the axial piston type, associated with an epicycloidal reducer unit which transmits the motion to the crawler tracks of the mini excavator. [0006] The hydraulic motors associated with the hydraulic supply circuit...

AI Technical Summary

Problems solved by technology

[0015] However, even these mini-excavators have the disadvantage that they disadvantageously require the intervention of the operator not only to carry out the normal driving and maneuvering of the machine, but also to change the displacement of the motor

[0016] Also, one has to take into account that while the mini excavator is moving, the displacement change is not at all gradual and comfortable as the excavator is allowed to work alternately in the two extreme configurations of the motor (minimum or maximum displacement) ground, and small excavators are usually only operated by skilled and dedicated operators

Images