EP4653621A1

EP4653621A1 - Motor grader

Info

Publication number: EP4653621A1
Application number: EP25176498.1A
Authority: EP
Inventors: Daniele ZAFARANA; Lorenzo MELIS
Original assignee: CNH Industrial Italia SpA
Current assignee: CNH Industrial Italia SpA
Priority date: 2024-05-24
Filing date: 2025-05-14
Publication date: 2025-11-26

Abstract

Motor grader comprising a frame formed by a front portion (FF) hinged to a rear portion (RF), a front axle (FA) associated with the front portion (FF) of the frame, in which the front axle is steerable with respect to the front portion ( FF) of the frame, a main levelling blade (LB) having an elongated shape so as to define a longitudinal development axis, associated with the front portion of the frame by means of a support system (TT, HA, PA), the vehicle including an auxiliary motor grader (B1, B2) of longitudinal shape arranged parallel to the main levelling blade (B) and configured to slide telescopically with respect to the main levelling blade.

Description

Field of the invention

The present invention relates to the field of motor graders. Hereinafter, grader means a motor grader.

State of the art

Motor graders are work vehicles V that can be used in agriculture and on construction sites, with reference to figure 1 of the prior art. Generally, graders equipped with tracks are used in the agricultural sector, while wheeled graders are implemented in the construction of buildings and infrastructures.
Motor graders are generally self-propelled vehicles equipped with two frame portions FF, RF hinged together by a hinge H, in which the rear portion includes a pair of driving axles RA1, RA2 and the front portion includes a steering axle FA. The rear axles can be replaced by a pair of tracks.
A structure generally named as "yoke" is connected to the front portion of the frame, in an intermediate position between the front axle and the hinge, to support a levelling blade B or "moldboard blade", whose position is regulated using dedicated actuators HA, PA.
The levelling blade is hinged by a plate TT, generally named "turntable" which allows limited movements around an operationally approximately vertical axis.
The inclination of the blade can be adjusted using a suitable PA hydraulic actuator generally called "Blade pitch".
The blade pitch actuator can induce a limited variation in the angle of attack of the blade on the ground.
A vertical HA actuator allows the turntable and with it the levelling blade to be raised and lowered.
The assembly of the turntable and actuators defines a support system for the levelling blade operationally connected to the front FF part of the frame.
In particular, as is known, the front part of the frame is arched to define a cradle in whose convexity it collects the support system of the levelling blade.
The levelling blade has a longitudinal development. It has a predetermined length, generally calculated according to the possible materials to be levelled.
The surface of land treated by the vehicle obviously depends on the length of the levelling blade. When the material is particularly light and flexible enough to be easily levelled, the operator can decide to operate at a higher speed, but this risks compromising the quality of the workmanship and increasing fuel consumption.
Unless specifically excluded in the detailed description that follows, what is described in this chapter is to be considered as an integral part of the detailed description.

Summary of the invention

The aim of the present invention is to indicate a motor grader capable of reducing processing times when the material to be levelled is sufficiently light and pliable. The basic idea of the present invention is to equip the main levelling blade with at least one auxiliary blade that can be deployed laterally with respect to it.
In other words, the vehicle is equipped with a first levelling blade and a second levelling blade arranged parallel to the first to slide with respect to the first, extending axially beyond the first blade. It is a telescopic movement.
According to a preferred variant of the invention, the vehicle is equipped with a second and a third blade suitable to be deployed laterally at the opposite ends of the first levelling blade.
In the following, "first" or "main" attributes referring to the levelling blade are exchangeable.
Advantageously, this allows the surface area of land worked to be increased at the same time, increasing the throughput of the vehicle.
The dependent claims describe preferred variations of the invention, forming an integral part of the present description.

Brief description of the figures

Further objects and advantages of the present invention will be clear from the following detailed description of an example of its implementation (and its variants) and from the attached drawings given purely for explanatory and non-limiting purposes, in which:

figure 1 shows a motor grader according to the prior art;
figures 2 and 3 show two perspective and side views respectively of a vehicle according to the present invention;
figures 4 - 6 show possible configurations assumed by the blades of the present invention.

The same reference numbers and letters in the figures identify the same elements or components or functions.
It should also be noted that the terms "first", "second", "third", "higher", "lower" and the like may be used here to distinguish various elements. These terms do not imply a spatial, sequential, or hierarchical order for the modified elements unless specifically indicated or inferred from the text.
The elements and characteristics illustrated in the different preferred embodiments, including the drawings, can be combined with each other without departing from the scope of protection of the present application as described below.

Detailed description

The present invention, with reference to figures 2 and 3, shows a motor grader V having a main blade B substantially of known shape and dimensions and at least one auxiliary blade B1 arranged parallel to the main blade and arranged to slide axially, i.e. parallel to its own longitudinal axis of development, to project laterally with respect to the main blade, increasing the footprint of soil worked at the same time.
The lateral orientation herewith referred is parallel to the ground being worked on. In fact, the orientation of a grader blade of a motor grader is known.
In the following, "blade" means "levelling blade".
The auxiliary blade preferably has a shape identical to the main blade and can have a longitudinal development equal to or shorter than the main blade.
The axial movement of the auxiliary blade defines a telescopic motion with respect to the main blade. Preferably, the vehicle V is equipped with a left auxiliary blade B1 and a right auxiliary blade B2.
The left (or right) auxiliary blade is arranged to assume a first operational configuration in which it is entirely covered, in operational terms, by the main blade and a second operational configuration in which it protrudes laterally to increase the surface of worked land.
The main blade is supported by a support system that includes a turntable TT, a pair of vertical actuators arranged to raise and lower the turntable and at least one pitch actuator. The angle of attack of the blade on the ground is defined as pitch.
The auxiliary blades B1 and B2 are also supported by the turntable TT through a sliding support device oriented parallel to the main blade B, so that regardless of the orientation of the main blade with respect to the longitudinal axis of development of the vehicle, the sliding movement of the auxiliary blades is always telescopic, i.e. parallel to the main blade and to the plane defined by the turntable itself.
According to a preferred variant of the invention, the vehicle is equipped with a main blade and an auxiliary blade having a longitudinal extension approximately equal to the main blade and the deployment of the auxiliary blade involves a movement of the main blade in the opposite direction.
Preferably, in conditions of deployment of the auxiliary blade, the latter partially overlaps with the main blade in terms of operation on the terrain being levelled.
Therefore, when it is stated that the auxiliary blade is positioned behind the main blade, this implies that it is not operational as it is "covered" during the advancement of the vehicle by the projection of the main blade.
The adjustment of the pitch angle of the auxiliary blade, according to a preferred aspect of the invention, is achieved by the same actuator as the main blade.
In particular, the auxiliary blades slide axially with respect to the main blade, to remain constantly parallel with the main blade, regardless of the pitch angle of the main blade.
A possible solution is shown with the help of figures 4 - 7, in which it is disclosed that the main blade B is hinged in X1 to a support element T1 integral with the turntable TT, and the actuator PA is hinged on the same element of support in one end P1 and to the blade in an end P2 opposite to the first.
The auxiliary blade is hinged to the support element T1 at point Y1 and a connecting rod BL is hinged at its opposite ends X2, Y2 respectively on the main blade and on the auxiliary blade to define an articulated quadrilateral. Figures 4 - 7 show respective angles of attack of the blades with respect to the ground G. It should be noted that regardless of the angle of attack, the main blade and the auxiliary blade always consistently show the same angle of attack or pitch.
Constructive variations to the non-limiting example described are possible, without departing from the scope of protection of the present invention, including all the equivalent embodiments for a person skilled in the art, to the content of the claims.
From the above description, the person skilled in the art is able to realize the object of the invention without introducing further construction details.

Claims

Motor grader comprising a frame formed by a front portion (FF) hinged to a rear portion (RF), a front axle (FA) associated with the front portion (FF) of the frame, in which the front axle is steerable with respect to the front portion ( FF) of the frame, a main levelling blade (B) having an elongated shape so as to define a longitudinal development axis, associated with the front portion of the frame by means of a support system (TT, HA, PA), the motor grader being characterized by the fact to include at least one auxiliary levelling blade (B1, B2) of longitudinal shape arranged parallel to the main levelling blade (B) and configured to slide telescopically with respect to the main levelling blade.
Motor grader according to claim 1, wherein said telescopic sliding is made to allow the auxiliary levelling blade a position in which it is integrally posterior to the main levelling blade and a second position in which it projects laterally with respect to the main levelling blade to increase a surface of soil (G) treated simultaneously by the main levelling blade and the auxiliary levelling blade.
A motor grader according to claim 2, wherein said auxiliary blade is arranged to slide telescopically relative to the main grading blade and the main blade is arranged to slide telescopically relative to the auxiliary blade in a direction opposite to the auxiliary grading blade.
A motor grader according to claim 2, including first (B1) and second auxiliary levelling blades (B2) and wherein said first auxiliary levelling blade is arranged to slide telescopically in a direction opposite to the second auxiliary levelling blade so that in said second position the first and second levelling blades project onto opposite sides of the main levelling blade.
Motor grader according to any of the previous claims, further equipped with a support system for the main levelling blade and said auxiliary levelling blade is configured to force the auxiliary levelling blade to constantly assume the same angle of attack on the ground as the main levelling blade.
A motor grader according to claim 5, wherein said support system includes a wishbone configuration (B, B1, BL, T1) between said main grader blade and said auxiliary grader blade.