Work vehicle including loader work device

Provided is a work vehicle including a cabin and a loader work device. The work vehicle includes: a vehicle main body; a main body rear; front and rear wheels; a bucket; a lifting arm connected to the bucket to lift the bucket; a boom support connected to the lifting arm; a rear link having one end coupled to a first boom support hinge part of the boom support and an opposite end coupled to a rear hinge part of the main body rear; a boom cylinder having one end coupled to a second boom support hinge part of the boom support to rotate the boom support; and a rotation link having one end coupled to a third boom support hinge part of the boom support and an opposite end coupled to a front hinge part of the vehicle main body.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a loader work device of a work vehicle, and more particularly, to a loader work device capable of moving a bucket connected to a loader vertically upward through a simple structure of a shaft and a cylinder. The loader work device may be used in industrial vehicles, construction equipment, and agricultural loader work machines, and may also be used in a skid steer loader (SSL) or a compact track loader (CTL).

2. Description of the Related Art

A loader work machine is provided with a pair of left and right arms on both sides of a base frame of a work vehicle, and a work tool (bucket) on ends of the left and right arms.

In addition, the loader work machine is provided with a hydraulic actuator for operating the work tool, and the ends of the left and right arms may vertically move up/down on a front side of the base frame through a pair of first lift links provided on rear left and right sides of the base frame and a pair of second left links provided on front left and right sides of the base frame. For example, the above loader work machine is described in the following case of Patent document 1.

FIG. 1shows a state in which a bucket is being lifted in a conventional loader work machine.

Referring toFIG. 1, a loader work device is provided in a vehicle such as a tractor, a wheel loader, a skid loader, and a track loader, and the loader work device includes a bucket4for lifting a conveyance target load.

In detail, in the case of the conventional loader work device, a lifting arm30having one side connected to the bucket4and an opposite side connected to a rear side of a vehicle main body1, a lifting arm hinge part31serving as a rotation center of the lifting arm30, a boom cylinder20for transmitting a force such that the lifting arm30rotates or moves up/down, and a cylinder hinge part21serving as a rotation center of the boom cylinder20are connected.

In addition, in the case of the conventional loader work device, the lifting arm hinge part31and the cylinder hinge part21are provided on the rear side of the vehicle main body1, and rotate corresponding to the upward and downward movement of the lifting arm30according to movement caused by extension or compression of the boom cylinder20.

Further, a cabin in which a user rides is provided between a front wheel2and a rear wheel3of the vehicle, and the cylinder hinge part21of the boom cylinder20and the lifting arm hinge part31, which are components for rotating the lifting arm30, are located on a rear side of the cabin or located over the rear wheel3.

Due to the above structural problem, as shown inFIG. 1, when the bucket4is lifted up vertically (or when the lifted bucket4is moved down), a movement path of the bucket4is as follows that the bucket4moves forward by a distance A or moves rearward by a distance B according to the rotation of the lifting arm30upon the lifting of the bucket4.

In other words, since the lifting arm30rotates about the lifting arm hinge part31, the bucket4located at an end of the lifting arm30moves forward (A) or rearward (B) while being lifted. This causes the vehicle to move rearward by the predetermined distance A or to move forward by the predetermined distance B in order to move the bucket4vertically upward.

In the case of lifting the bucket of the loader work device vertically upward, a large amount of work loss may be caused when the vehicle moves forward or rearward according to the forward/rearward movement of the bucket4.

SUMMARY OF THE INVENTION

The present invention is directed to provide a loader work device capable of minimizing fluctuation/movement of a bucket in a forward or rearward direction when the bucket is moved up/down.

In addition, the present invention is directed to propose a loader work device which has a simple structure of a link and a hinge part to vertically lift up and down the bucket so that an increase in manufacturing costs may be suppressed, and it may be advantageous for maintenance and repair works.

According to the present invention, there is provided a work vehicle including a cabin and a loader work device, the work vehicle including: a vehicle main body for supporting the cabin; a main body rear disposed on a rear side of the vehicle main body; front and rear wheels for moving the work vehicle; a bucket for receiving a load; a lifting arm connected to the bucket to lift the bucket up and down; a boom support connected to the lifting arm; a rear link having one end coupled to a first boom support hinge part formed in the boom support and an opposite end coupled to a rear hinge part formed in the main body rear; a boom cylinder having one end coupled to a second boom support hinge part formed in the boom support to rotate the boom support such that the lifting arm rotates or moves up and down; and a rotation link having one end coupled to a third boom support hinge part formed in the boom support and an opposite end coupled to a front hinge part formed at a front end of the vehicle main body.

According to the loader work device of embodiments, when the bucket is vertically moved up and down, the forward/rearward fluctuation can be minimized, and the upward/downward movement can be performed more accurately.

In addition, the number of components such as arms, links, and hinges is reduced, and hinge parts are shared so that a cost for the maintenance and repair works as well as a manufacturing cost can be reduced.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 2 to 5are views showing a configuration and an operation process of a loader work device according to a first embodiment of the present invention, andFIG. 6is a view showing positions of the buckets during an operation of the loader work device according to the first embodiment.

First, referring toFIGS. 2 to 5, in a loader work device of the embodiment, a vehicle such as a tractor and an industrial vehicle includes a cabin5in which a user rides, and a vehicle main body1configured to support the cabin5and connected with a front wheel2and a rear wheel3.

In addition, a main body rear7for receiving components such as an engine is disposed on a rear side of the vehicle main body1.

The loader work device of the embodiment includes a lifting arm200connected to the bucket4for loading or receiving a load, and a boom cylinder20for providing a force such that the lifting arm200moves up and down. In addition, the loader work device is provided with a boom support100for connecting the lifting arm200to the boom cylinder20, and the boom support100has three hinge parts at mutually different positions.

In detail, the boom support100has a first boom support hinge part110to which a rear link70is rotatably connected, a second boom support hinge part120to which the boom cylinder20is connected, and a third boom support hinge part130connected to a rotation link300connected to a front side of the vehicle main body1.

The first to third boom support hinge parts are disposed at mutually different positions in the boom support100. In particular, the second boom support hinge part120is disposed at a position higher than the third boom support hinge part130so that the bucket may be vertically lifted up and down. The boom support100is curved in a ‘reverse-L’ shape, or is partially bent.

In the present embodiment, in order to suppress the movement of the bucket4in a forward/rearward direction when the lifting arm200rotates, the front hinge part50serving as the rotation center of the rotation link300is formed above the front wheel2, and the rear hinge part60serving as the rotation center of the boom cylinder20is located on a rear side of the rear wheel3of the vehicle.

In particular, the rotation center of the rear link70connected to the first hinge part110of the boom support100is the same as the rotation center of the boom cylinder20. In other words, since both ends of the rear link70and the boom cylinder20are connected to the rear hinge part60, the number of hinge parts of the rear link70and the boom cylinder20may be reduced so that a cost for maintenance and repair works as well as a manufacturing cost can be reduced.

The rear hinge part60is formed in the main body rear7which is provided on the rear side of the vehicle main body1, and such positioning takes into consideration the rotation of the lifting arm200and a movement position of the bucket4.

The rear link70has one end connected to the rear hinge part60, and an opposite end connected to the first boom support hinge part110. When the boom support100rotates (e.g., in a counterclockwise direction) by an operation of the boom cylinder20, the rear link70serves to move the boom support100rearward by a predetermined distance.

The rotation link300has one end connected to the front hinge part50which is formed vertically above the front wheel2of the vehicle, and an opposite end connected to the third boom support hinge part130of the boom support100. When the boom support100rotates by the operation of the boom cylinder20, the rotation link300serves to assist the rotation of the boom support100and support the lifting arm200coupled to the boom support100.

When the bucket4moves vertically upward in a state where the bucket4is moved down as shown inFIG. 2, the boom support100rotates in a counterclockwise direction while moving rearward by a predetermined length by the operation of the boom cylinder20, and the rotation link300rotates in a clockwise direction at a predetermined angle.

In addition, the rear link70rotates in the counterclockwise direction, which is the same as a rotation direction of the boom support100, at a predetermined angle.

As shown inFIG. 5, a length of the rotation link300has to be set such that the third boom support hinge part130forms an acute angle with the lifting arm200at a height corresponding to an uppermost position of the bucket4when the bucket4is lifted up.

As described above, since the boom support100has the first to third boom support hinge parts, and particularly, since the second boom support hinge part120is formed at the position higher than the third boom support hinge part130, the boom support100may be partially curved. In addition, in operation states shown inFIGS. 2 to 5, the second boom support hinge part120is designed to be maintained at the position higher than the third boom support hinge part130even when the boom support100rotates.

With the above structures, the rotation of the rotation link300about the front hinge part50and the rotation of the boom cylinder20and the rear link70about the rear hinge part60may allow the bucket4to vertically move up/down while minimizing forward/rearward fluctuation of the bucket4.

In the boom support100, the first boom support hinge part110is formed rearward (left side in the drawing) of the vehicle, the third boom support hinge part130is formed forward (right side in the drawing) of the vehicle, the second boom support hinge part120is disposed forward of the third boom support hinge part130when the bucket4is located at a lowermost position, and the second boom support hinge part120is disposed between the first boom support hinge part110and the third boom support hinge part at a height at which the bucket4is lifted by a predetermined height or more.

In addition, the front hinge part50, to which the opposite end of the rotation link300having the one end connected to the third boom support hinge part130is coupled, is formed under the cabin5located on the front side of the vehicle main body1.

In addition, the opposite end of the rear link70coupled to the first boom support hinge part110and the opposite end of the boom cylinder20coupled to the second boom support hinge part120are coupled to the rear hinge part60. When the bucket4is lifted by the operation of the boom cylinder20, the rear link70initially rotates about the rear hinge part60in a direction which is the same as a rotation direction of the boom cylinder20, and then the rear link70and the boom cylinder20rotate in opposite directions, so that an interval (angle) between the rear link70and the boom cylinder20becomes narrow. On the contrary, when the bucket4moves down after being lifted up, the rear link70and the boom cylinder20rotate in opposite directions so that the interval (angle) between the rear link70and the boom cylinder20is increased.

Due to the above configuration, as shown inFIG. 6, when the bucket4moves forward/rearward upon the lifting up/down of the bucket4, the bucket4may move very slightly, and there is no inconvenience that the vehicle has to move in the forward/rearward direction.

FIGS. 7 to 9are views showing the configuration and the operation of the loader work device according to a second embodiment of the present invention.

A cover part for the boom support100and the main body rear7is shown by solid lines inFIG. 7, and components of the loader work device of the present invention are shown by solid lines inFIG. 8.

Operations of the second embodiment are performed similarly to the loader work device of the first embodiment described above. However, in the second embodiment, the lifting arm200to which the bucket4is coupled and the boom support100are formed in a single configuration, and particularly, the one end of the rotation link300is disposed toward a center of the vehicle main body1.

In other words, in the case of the loader work device of the present invention, the one end of the rotation link300is coupled to the front hinge part50formed in the vehicle main body1or the cabin5, and the opposite end of the lifting arm200is coupled to the third boom support hinge part130. However, the front hinge part50may be located above the front wheel2, or disposed above between the rear wheel3and the front wheel2.

In addition, depending on a size of the vehicle and a length of the lifting arm200, the rear hinge part60to which the boom cylinder20and the rear link70are coupled may also be located above the rear wheel3of the vehicle or on the rear side of the rear wheel3.

The loader work device of the second embodiment may also vertically lift up/down the bucket4without the forward/rearward fluctuation of the bucket4as shown inFIG. 9, and a structure of the loader work device of the second embodiment is also configured such that the boom cylinder20and the rear link70are coupled to the rear hinge part60so that the structure can be simplified.