Patent Application
20210172154
The disclosure relates to the field of backhoe loaders.
A backhoe loader is a machine that comprises a loader generally towards the front of the machine and a backhoe generally towards the back of a machine. A typical backhoe loader is shown in
Conventionally, a pair of backhoe control sticks is provided to operate the backhoe and these are usually mounted between the seat and the rear of the cab. The exact positions of the pair of backhoe control sticks may be adjustable to provide easier access to the seat and for operator comfort. Conventionally, one loader control stick is provided to operate the loader and this is usually mounted between the seat and the front of the cab. The exact position of the one loader control stick may be adjustable to provide easier access to the seat and for operator comfort.
Accordingly, three control sticks may be provided in total.
When facing forwards, the pair of backhoe control sticks will be behind the seat and, when facing backwards, the loader control stick will be behind the seat. Accordingly, access to at least one of the control sticks is always restricted. A skilled operator may be able to operate a control stick located behind the seat but this may be uncomfortable and, in any case, freedom of movement of the operator may be limited such that precision control may be difficult.
Against this background, in a first aspect there is provided a backhoe loader comprising:
In this way, functionality of the first and second control sticks may be dependent upon seat orientation.
In a second aspect, there is provided a backhoe loader comprising:
In this way, simultaneous control of both the loader assembly and the backhoe assembly may be facilitated using the first and second control sticks.
In a third aspect, there is provided a backhoe loader comprising:
In this way, first and second control sticks may be used for any of the following: to control the backhoe assembly; to control the loader assembly; and in a hybrid configuration to control both the backhoe assembly and the loader assembly.
A specific embodiment of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:
The backhoe loader comprises a cab 110 from which an operator may operate the backhoe loader. The backhoe loader further comprises a loader assembly 120 forward of the cab 110 and a backhoe assembly 130 rearward of the cab 110. The backhoe assembly 130 may comprise a boom 132 hingedly attached, at a first end of the boom 131, to the machine 100 via an attachment 111. The backhoe assembly 130 may further comprise an arm 135 hingedly attached at a first end of the arm 134 to a second end of the boom 133 opposite the first end of the boom 131. The arm 135 may comprise a coupling 137 by which an implement such as a bucket 138 may be attached to the arm 135.
The loader assembly 120 may comprise a coupling 122 enabling attachment of a loader bucket 121 or other implement, for example forks.
The cab 110 comprises a seat assembly 200 rotatable between a forward facing orientation (as shown in
In the forward facing orientation, the operator faces regular driving controls such as accelerator, brake and steering wheel 201. In addition, in the forward facing orientation the operator has access to a loader control stick 210 by which the loader assembly 120 may be controlled. It is common for the loader control stick 210 to be towards a right side of a main cab console.
In a known arrangement, the loader control stick 210 may be moved forwards and backwards to lower and raise the loader assembly 120, respectively. In the known arrangement, the loader control stick 210 may be moved left and right to tilt the loader implement (e.g. loader bucket 121 or forks) upwards and downwards, respectively. In this way, an operator can control the loader assembly 120 using loader control stick 210.
In the rear facing orientation, the operator faces first and second backhoe control sticks 220, 230 by which the backhoe assembly 130 may be controlled. The first backhoe control stick 220 may be located on a right side of a rear console within the cab 110 and the second backhoe control stick 230 may be located on a left side of the rear console within the cab 110.
In a first known arrangement, the first backhoe control stick 220 may be moved left and right to curl the bucket 138 and dump the bucket 138, respectively, and may be moved forwards and backwards to move the arm 135 out and in, respectively. In the first known arrangement, the second backhoe control stick 230 may be moved left and right to swing the boom 132 left and right, respectively, and may be moved forward and backwards to move the boom 132 down and up, respectively. This first known arrangement is commonly adopted in backhoe loaders.
A summary of the control functionality in the first known arrangement is illustrated in
In a second known arrangement, the first backhoe control stick 220 may (as in the first known arrangement) be moved left and right to curl the bucket and dump the bucket 138, respectively, and may (by contrast with the first known arrangement) be moved forward and backwards to move the boom 132 down and up, respectively. In the second known arrangement, a second backhoe control stick 230 may (as in the first known arrangement) be moved forwards and backwards to move the arm 135 out and in, respectively, and may (by contrast with the first known arrangement) be moved left and right to swing the boom 132 left and right, respectively. This second known arrangement is commonly adopted in excavators.
A summary of the control functionality in the first known arrangement is illustrated in
In both first and second known arrangements, eight functions are available for controlling the backhoe assembly 130 using first and second backhoe control sticks 220, 230 (four functions on each of the two backhoe control sticks 220, 230). As such, an operator may control eight functions of the backhoe assembly 130 the two control sticks 220, 230.
In the arrangements so far described, if an operator is facing backwards then both backhoe control sticks 220, 230 are in front of the operator while the loader control stick 210 is behind the operator. Conversely, if an operator is facing forwards then the loader control stick 210 is in front of the operator but the first and second backhoe control sticks 220, 230 are behind the operator. Given that when an operator is facing either backwards or forwards at least one control stick is behind the operator this may limit access to the controls and/or may restrict the precision of operation achievable by the operator.
In the arrangements so far described, the control sticks 220, 230 are frequently hydraulic control sticks wherein the control sticks 220, 230 provide mechanical control of hydraulic valves and actuators that drive the backhoe actuators and drive the loader actuators.
In accordance with the present disclosure, instead of three control sticks (210, 220, 230), one of which is located towards the front of the cab 110 and two of which are located towards the rear of the cab 110, there are two control sticks (first and second control sticks 310, 320) which are located on opposite sides (right and left) of the seat assembly 300 and which rotate with the seat assembly 300.
Rather than each control stick having a fixed functionality, the functionality of the first and second control sticks 310, 320 is dependent upon additional factors.
This may be made possible by using electronic control sticks that drive an electronic controller which then drives hydraulics, rather than by having control sticks that mechanically actuate hydraulic valves. In this way, variable functionality is enabled by the electronic controller rather than by altering hydraulic connections.
One factor that may determine the functionality of the first and second control sticks may be the direction in which the seat assembly 300 is facing. A seat orientation sensor may be provided for providing a seat orientation signal by which control stick functionality may be influenced.
There may be first, second and third modes of operation, shown schematically in
In the first mode, signals from both the first control stick 310 and second control stick 320 are used to control operation of the backhoe assembly 130. This would replicate what may be ordinarily expected by an operator using a machine in accordance with the prior art shown in
In the second mode, signals from the first control stick 310 may be directed to control operation of the loader assembly 120 while signals from the first control stick 320 may remain unused. This would replicate what may be ordinarily expected by an operator using a machine in accordance with the prior art shown in
In the third mode, hybrid functionality may be provided whereby (a) signals from the second control stick 320 may be used to control operation of the loader assembly 120 and (b) signals from the first control stick 310 may be used to control operation of the backhoe assembly 130.
One consequence of this hybrid functionality is that, since only one of the two control sticks 310, 320 is available for backhoe operation, only four functions are possible rather that the eight that would be achievable with two control sticks for backhoe operation.
The four functions available with the single backhoe control stick may be boom down, boom up, arm out and arm in. Accordingly, swing left, swing right, bucket curl and bucket dump may not be available. The reason for the choice of available functions may be related to the usefulness of those functions for the purpose of movement of the machine (e.g. in a line parallel to a trench being dug). In other words the available functions may be those which facilitate use of the backhoe to lift the rear wheels of the machine off the ground and then use the backhoe to propel the machine on its front wheels.
Which mode is active at any particular time may be dependent upon factors including (a) seat assembly orientation (b) safety trigger and (c) manual override of default function to select alternative functionality. An example implementation of mode availability is shown in
For example, the first mode may be available by default if the seat orientation sensor determines that the seat assembly 300 is in a rearward orientation (such that backhoe control is fully available when facing the backhoe assembly 130). The second mode may be available by default if the seat orientation sensor determines that the seat assembly 300 is in a forward facing orientation (such that loader control is available when facing the loader assembly 120).
It may be that the first mode is also available by default if the seat orientation sensor determines that the seat assembly is in neither a forward facing nor a rearward facing orientation. An operator is likely to move into or out of the seat when it is at a midway position between forwards and backwards since that may be the orientation in which the seat is most accessible via a door of the cab 110. Since it may be desirable to avoid accidental or unintended movement of implements during operator ingress/egress from the cab 110, availability of the controls when the seat is neither facing forwards nor backwards may also require activation of a safety trigger.
While it may be convenient for use of the first and second control sticks to be dictated by default by the position of the seat assembly, it may also be desirable to allow an operator to alter the default functionality. An example of alternative functionalities is also shown in
In accordance with the example alternative modes shown in
Selection of alternative functionality may be made by an operator using, for example, an alternate setting actuator, which may be a switch on a console within the cab 110.
