EP1870373A2

EP1870373A2 - Control apparatus for excavator machines

Info

Publication number: EP1870373A2
Application number: EP07110465A
Authority: EP
Inventors: Roberto Ros
Original assignee: Casagrande SpA
Current assignee: Casagrande SpA
Priority date: 2006-06-21
Filing date: 2007-06-18
Publication date: 2007-12-26
Also published as: EP1870373A3; EP1870373A8; ITUD20060160A1

Abstract

A control apparatus (10) for an excavator machine (19), having one or more flexible pipes (13) to collect debris and/or deliver water, and/or to contain hoses for fluid-dynamic and/or electric commands, comprises means (11) to wind/unwind the flexible pipe (13), rotating around an axis (Y) of rotation in order to effect operations to wind/unwind the pipes (13) along an axis or direction (X) of winding/unwinding, variable during said winding/unwinding operations. The winding means (11) is selectively inclined according to the number of revolutions made by the winding means (11) during the operations to wind/unwind the flexible pipes (13).

Description

FIELD OF THE INVENTION

The present invention concerns a control apparatus for excavator machines which is suitable to control and regulate the position of the winding/unwinding means, for example a drum or bobbin, for flexible pipes, for example, but not only, to suck up the excavation debris and/or to deliver fluid to remove the debris.
To be more exact the present invention concerns a control apparatus able to modify the position of the winding means, so that said pipe is always wound/unwound accurately and regularly as the winding/unwinding position varies, that is, as the filling level of the winding means varies, whether said means be a drum, a bobbin or other analogous or similar means.
US-A1-2005/0056819 , JP-A-2000-351581 and WO-A-03/053821 disclose prior art solutions which include the features of the preamble of the main claim.

BACKGROUND OF THE INVENTION

In known excavator machines having a crane equipped with an arm which maneuvers the excavation means, the pipes to suck up the debris and/or to deliver the fluid that removes the debris are guided through a fixed articulation point, on one side towards the excavation and on the other side towards cylindrical drums. The winding/unwinding of the pipes is achieved by means of said cylindrical drums, or reels, which rotate on themselves, fixed with respect to the excavator machine and normally equipped with guides disposed helically with a constant pitch, in which adjacent portions or spirals of the pipe are housed.
During the winding/unwinding operation, the pipe is mechanically accompanied from the fixed articulation point towards the relative helical guide by means of a roller, made rotary by deriving the rotation motion from the cylindrical drum by means of a slider which cooperates with said helical guides.
However, in known excavation machines, the winding system is greatly influenced by the position of the point of entry/exit of the pipe as the filling level of the drum or reel varies. It therefore happens that the pipe, as it winds or unwinds, can be disposed too much inclined with respect to the axis of the cylindrical drum, that is, it forms an acute angle of less than a determinate value and too distant from the ideal condition of a right angle. Consequently, it deforms, it does not wind correctly and, in the event of overlapping of the pipes, it is damaged.
To be more exact, this problem occurs if pipes of great length are needed, in order to reach great depths in excavation, since in this case either very long drums must be used, or two or more layers must be formed on the same drum: in both cases the variation in the direction of entry/exit of the pipe with respect to the fixed point is very accentuated and entails problems of regularity. Using a large-size drum, both axially and radially, also entails problems in the considerable increase in bulk of the excavator machine. However, if the bulk of the excavator machine must be limited, alternative solutions have been proposed which provide to lengthen the arm of the crane. But apart from increasing the costs of making the crane, this also determines a reduction in the range of the arm of the crane and therefore the need to reduce the excavation forces applied to the excavation means too, which is detrimental to the quality and efficiency of the excavation made.
Moreover, as the position of exit/entry from/into the drum varies, the pipes are not always guided correctly in the relative helical guides, which causes possible deformations and breakages of the pipes.
Excavator machines are also known which have means to guide the pipe that causes the pipe to wind in multiple layers around a winder, but in the same position to substantially form a winding disk with a thickness determined by the diameter of the pipe and a diameter which is a function of the number of winding revolutions on itself. These known machines also have the disadvantage that they can use pipes which are not too long, to prevent an excessive increase in the sizes, particularly the diameter, of the winding disk, and can cause deformations and breakages of the pipe due to the stresses to which it is subjected both by the winder and also by the overlapping layers of pipe.
Purpose of the present invention is to achieve a control apparatus which allows to wind/unwind the pipe that sucks up the debris and/or delivers the fluid that removes the debris in an excavator machine around the winding means in a correct and accurate manner, as the filling level of the winding drum or reel varies, preserving the pipe from deformations and damage.
Another purpose is also to allow winding over several layers, using a control apparatus which is economical, easy to make and compatible with any bulk of the excavator machine required.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the main claim, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.
A control apparatus according to the present invention can be applied to an excavator machine having at least a flexible pipe, for example to suck up the debris by means of a fluid, and/or to deliver a fluid to remove the debris, and/or hoses, individual or in bundles, for fluid-dynamic and/or electric commands, guided through a fixed articulation point, on one side towards the excavation and on the other side towards means to wind/unwind said flexible pipe.
The winding means is able to rotate around an axis of rotation in order to effect operations to wind/unwind said pipe, along an axis or direction of winding/unwinding. The axis of winding/unwinding is substantially defined by the line that connects the point of entry/exit of the flexible pipe into/from the winding means, which is continuously variable during the winding/unwinding step, to the fixed articulation point.
The winding/unwinding means consists in one embodiment of the invention of a drum or reel, but a bobbin may equally well be used, or other suitable analogous or similar means.
In accordance with the above purposes, the control apparatus according to the present invention has said winding means able to be selectively inclined during the winding/unwinding operations according to the level of filling of the winding means by the flexible pipe, that is, the number of revolutions made by the flexible pipe around the winding means. In this way, said axis of winding/unwinding is always substantially perpendicular, or deviating from the perpendicular with a desired margin of tolerance, with respect to the axis of rotation of the winding means, although the axis of winding/unwinding is continuously modified, assuming a plurality of distinct angular positions during the winding/unwinding operations, according to the filling level of the winding means.
According to the present invention, the control apparatus comprises sensor means able to measure at least one parameter between the number of rotations or revolutions made by said winding means, in this way determining, from the knowledge of the diameter of the drum, the position of entry/exit of the pipe, and the angle defined between the axis of rotation of the winding means and the axis of winding/unwinding.
Moreover, according to the invention, a command and control unit is provided which cooperates with said sensor means and, by activating actuator means, conditions the position of the winding means.
Advantageously, the control apparatus according to the present invention allows to wind/unwind said pipe around the winding means in a correct and accurate manner, as the filling level of the winding means varies, preserving the pipe from deformations and damage.
Furthermore, the pipe can be directed exactly according to the pre-determined winding disposition.
Advantageously, moreover, the present invention also allows to wind the flexible pipe in several layers, using a control apparatus that is economical, easy to make and compatible with any bulk required for the excavator machine.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

fig. 1 is a plane view of a control apparatus according to the present invention, shown in an operating condition, associated with an excavator machine;
fig. 2 is a partial lateral view of the control apparatus in fig. 1;
fig. 3 is a plane view of the control apparatus in fig. 1 in another operating condition;
fig. 4 is a plane view of the control apparatus in fig. 1 in another operating condition;
fig. 5 is a detail of fig. 4; and
fig. 6 is a schematic representation of winding achieved by means of the control apparatus in fig. 1.

DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT

According to the present invention, fig. 1 shows a control apparatus 10 for an excavator machine 19 having at least a flexible pipe 13, in the case shown here, which is guided by guide means 18 through a fixed deflection device 17, or articulation point, on one side towards the excavation and on the other side towards two cylindrical drums 11, opposite each other, that is, disposed on opposite sides of the machine 19.
Each cylindrical drum 11 is able to rotate around its own longitudinal axis Y in order to effect operations to wind/unwind said pipe 13 along an axis or direction X of winding/unwinding, which is defined as the straight line that joins the point of entry/exit into/from the cylindrical drum 11 of the flexible pipe 13 with said fixed deflection device 17 and whose position is variable, substantially continuously, during said winding/unwinding operations.
The pipe 13 can be wound to form one or more layers on the lateral surface of the cylindrical drum 11.
For example, the two drums 11 can wind/unwind flexible pipes 13 of the same type, or one of the two drums 11 is able to wind/unwind a flexible pipe 13 to suck up and collect the debris deriving from the excavation, while the other drum 11 is able to wind/unwind a flexible pipe 13 normally consisting of hoses for fluid-dynamic and/or electric commands.
According to a variant, the control apparatus comprises a single drum 11 which winds/unwinds a corresponding flexible pipe 13.
In this case, the point of entry/exit of the flexible pipe 13 is defined by the point of upper tangency of the axis X with corresponding circular sections of the cylindrical drum 11 made perpendicularly, or deviating by a determinate amount with respect to the perpendicular, to said axis Y (fig. 2).
The cylindrical drum 11 has a lateral surface 22 around which the pipe 13 winds, in spirals substantially concentric to the axis Y (fig. 6).
According to one embodiment of the invention, the cylindrical drum 11 has guide seatings 12 which define a helical development along the axis Y, advantageously with a constant pitch, made on the lateral surface 22 and along which the pipe 13 winds.
According to a variant of the invention, the lateral surface 22 is substantially smooth and the cylindrical drum 11 is equipped with containing and guiding spirals with a helix 12, which assist the winding of the pipe 13 with a constant pitch helix.
The cylindrical drums 11 are made to rotate on themselves by means of motor means 25, of a known type.
Each cylindrical drum 11 is put with its longitudinal axis Y substantially parallel to the supporting plane of the machine 19, in this case the horizontal plane P (fig. 2), and is rotatably connected to the excavator machine 19.
Each cylindrical drum 11 is thus also inclinable around an axis Z, substantially orthogonal to the axis Y and to the supporting plane of the machine 19. The cylindrical drum 11 can therefore be selectively inclined, based on the commands of a command and control unit 20 and as will be explained hereafter, in a plurality of distinct angular positions, so that the axis Y is always substantially perpendicular or deviating from the perpendicular according to a desired margin of tolerance, with respect to the axis X of winding/unwinding.
Therefore, the axis Y, that is, its projection on the external periphery of the cylindrical drum 11, when seen plane, forms an angle β substantially a right angle or comprised in an interval of desired amplitude according to needs (figs. 1 and 4).
In other words, the axis X is always substantially perpendicular, or deviating from the perpendicular according to a desired margin of tolerance, with respect to a straight line parallel to the axis Y of rotation and passing through the point of entry/exit of the flexible pipe 13 into/from the cylindrical drum 11.
In fact, in a first position, the cylindrical drum 11 has the axis Y of rotation substantially orthogonal to the longitudinal direction S of the excavator machine 19, indicated by Y' in figs. 4 and 5, while in a second position (figs. 3, 4 and 5), continuously variable during winding/unwinding, the axis Y has its angular position modified and is inclined by a determinate angle α, other than 90°, in this case an acute angle, with respect to the longitudinal direction S of the excavator machine 19, indicated by Y" in figs. 4 and 5.
It is clear that the angle α can be either acute or obtuse, according to the winding/unwinding necessities and the position of the fixed deflection device 17 with respect to the drum 11.
The inclination movement of each cylindrical drum 11 is achieved by means of hydraulically actuated jacks 16, or other suitable and similar actuator means.
During said inclination movement, the operation to wind/unwind the flexible pipe 13 takes place and thus the axis X of winding/unwinding moves continuously, sweeping substantially at least a portion of plane parallel to the supporting plane of the excavator machine 19, between said first position and the second position, that is, between a lesser and a greater inclination of the drum 11 with respect to the longitudinal direction S of the excavator machine 19.
The flexible pipe 13 is associated by means of the guide means 18 with the deflection device 17, which is at partly rotatable on itself and substantially functions as a fixed point with respect to the excavator machine 19. The flexible pipe 13 is thus guided through the deflection device 17 towards the excavation, according to needs.
The winding/unwinding of the pipe 13 is achieved by rotating the cylindrical drum 11 around its own axis Y and by simultaneously inclining the cylindrical drum 11, which moves between said first and second position.
During this movement, the axis X of winding/unwinding, along which the flexible pipe 13 unwinds, is advantageously kept substantially perpendicular to said axis Y.
The winding spirals of the pipe 13 are thus disposed substantially parallel to each other and substantially orthogonal to said axis Y when they are wound/unwound around said lateral surface 22, that is, in other words, the winding spirals of the pipe 13 are parallel to the lateral surface 22 of the cylindrical drum 11.
In this way, we have an effective disposition of the pipe 13 around the lateral surface 22 of the cylindrical drum 11, irrespective of the angular position of the deflection device 17.
According to one form of embodiment of the present invention, the control apparatus 10 comprises sensor means 14, 15; the first are able to measure the number of rotations made by each cylindrical drum 11, thus determining the point of entry/exit of the flexible pipe 13 into/from the cylindrical drum 11, while the second are able to measure the angle between the axis Y of rotation of the cylindrical drum 11 and the axis X of winding/unwinding and/or the longitudinal direction S of the excavator machine 19.
In this case, the sensor means comprise digital encoders of lengths and angles, such as a first sensor of revolutions with an encoder 14 which measures the number of revolutions of the drum 11, and a second sensor of angles with an encoder 15, which in this case measures the amplitude of the angle α, in order to control the inclination.
According to the invention, said command and control unit 20 cooperates with the sensor means 14, 15, detecting the position in rotation of the cylindrical drum 11 and the number of revolutions made with respect to an initial reference position, in this case said first position of the cylindrical drum 11, in order to condition the jacks 16 and hence incline the cylindrical drums 11 according to the winding/unwinding needs.
According to a variant of the invention, the command and control unit 20 comprises a microprocessor and a controller of programmable logic circuits, PLC, to program the memories of the microprocessor in order to execute and control the logical functions.
In this way we obtain a correct winding position of the pipe 13 on the cylindrical drum 11, without any overlapping of the spirals of the pipe 13 during winding, nor any winding of the spirals with too great a pitch. Therefore, we prevent any damage to the pipe 13, which is usually caused by forced contacts against the cylindrical drum 11.
Advantageously, thanks to the great accuracy in the positioning and alignment of the cylindrical drum 11 with respect to the deflection device 17, it is also possible to wind the pipe 13 in spirals, not only axially in contact with the lateral surface 22 in a first winding layer 23 (fig. 6) which completely covers the latter, but also in a second layer 24, precisely overlapping the first layer 23, advantageously in multiple layers.
By multi-layer winding we mean that the flexible pipe 13, having effected a first filling of the drum 11 by means of a first layer which is coaxial with the axis Y, is wound again, in this case starting from outside the drum 11 towards the inside, achieving a second layer which develops according to the same axis Y and which is coaxial with the latter; a possible third or fourth layer are made in a substantially identical manner. This is advantageous also thanks to the application of the PLC control system, which is able to activate and de-activate the drums, both in rotation and in inclination, according to the state of winding/unwinding and the level of filling achieved by the winding drum.
It is clear that the deflection device 17 could be positioned in different zones than in the illustration in fig. 2, such as for example in proximity with the head of the arm of a crane or other, to satisfy contingent requirements.
The axis Z of inclination of the cylindrical drums 11 can therefore have other inclinations too, apart from being substantially perpendicular to the plane P.
It is clear that modifications and/or additions of parts may be made to the control apparatus 10 as described heretofore, without departing from the scope of the present invention.

Claims

Control apparatus for an excavator machine (19), having at least a flexible pipe (13) to collect debris and/or deliver water, and/or for hoses for fluid-dynamic and/or electric commands, comprising means (11) to wind/unwind said flexible pipe (13), able to rotate around an axis (Y) of rotation in order to effect operations to wind/unwind said pipe (13) along an axis or direction (X) of winding/unwinding, variable during said winding/unwinding operations, said winding means (11) being selectively inclinable according to at least the number of revolutions made by said winding means (11) during said operations to wind/unwind said flexible pipe (13), the apparatus further comprising actuator means (16) for varying the position of said winding means (11) and a command and control unit (20) for conditioning the functioning of said actuator means (16), characterized in that it further comprises at least one sensor selected between first sensor means (14) for measuring the number of revolutions made by said winding means (11) during the unwinding of the pipe (13) and second sensor means (15) for measuring the instantaneous angle formed between said axis (Y) of rotation of said winding means (11) and said axis (X) of winding/unwinding of said flexible pipe (13), wherein said command and control unit (20) controls the activation of said actuator means according to the detection of at least one between said first (14) and second (15) sensor means.
Control apparatus as in claim 1, characterized in that said winding means (11) is rotatably connected to said excavator machine (19) in order to be selectively inclined in a plurality of distinct angular positions, in which said axis (Y) of rotation is substantially perpendicular, or deviating from the perpendicular by a desired margin of tolerance, with respect to said axis (X) of winding/unwinding.
Control apparatus as in claim 1 or 2, characterized in that said first sensor means (14) are able to determine the instantaneous position of entry/exit of said flexible pipe (13) into/from said winding means (11).
Control apparatus as in claim 1, characterized in that said second sensor means (15) is also able to measure the angle between said axis (Y) of rotation and the longitudinal direction (S) of said excavator machine (19), and/or the angular position of said axis (Y) with respect to said axis (Z).
Control apparatus as in any claim hereinbefore, characterized in that it comprises guide means (12, 18) able to guide said flexible pipe (13) during said winding/unwinding operations.
Control apparatus as in any claim hereinbefore, characterized in that said winding means comprises at least a cylindrical drum (11)able to wind said flexible pipe (13) in a plurality of spirals to form one or more layers around a lateral surface (22) of said cylindrical drum (11), which are disposed substantially parallel to each other and substantially orthogonal to said axis (Y) when they are wound/unwound around said lateral surface.