DE2061176A1 - Control device for the working tools of earth moving machines - Google Patents

Description

tiiiua,.! December 11, 1970 8 monks 5,

s * λ \ r * t Erhardtetraße It TLlZ

. L-ati V. * <oepke Telephone 2406 75 D-9074

International Harvester Company 401, North Michigan Avenue Chicago, Illinois 60611 (V.St.A.)

Control device for the work tools of Earth moving machines

The invention relates to a control device for the work tools of earth moving machines, ins = particular of shovel or backhoe excavators, with a hydraulically pivotable lift in at least one level " linkage and hydraulically tiltable work tool.

The excavation linkage of such earth moving machines generally consists of a boom and a Handle on which the actual working tool, for example * wise an excavator shovel or an excavator bucket tiltable is hinged. The cantilever arm is usually about a vertical axis pivotable within a sector-shaped horizontal horizontal plane. The work tool can represent * moved back and forth in a vertical plane by folding the boom and stick back and forth be, for example when digging the ground, the work tool in front of the vehicle in the Soil is used and the excavator shovel by folding back the lifting rod in the direction of the Vehicle is moved, causing the shovel to fill with soil.

100029/1079
BATH ORIGINAL

The lift linkage and work tool are typically operated by hydraulic motors and hydraulic cylinders. A hydraulic motor with a vertical drive shaft is required to swivel the lifting rod in the horizontal plane. To operate the lifting linkage in the vertical plane, two hydraulic cylinders are required that can pivot the boom and the stick. Finally, a third hydraulic cylinder is not = agile, rotate around the working tool, or to be able to tilt necessary, also another Hydraulikzylin = W which can be provided to be able to move laterally around the entire Aushebegestänge with tools on a cross-beam, directly to, for example, in addition to the prior = to be able to trace trenches.

In order to control all movements of the parts of the lifting linkage and the working tool, a corresponding number of operating levers has been provided, which are operated individually and generally one after the other. In the aforementioned sequence of movement are therefore four, possibly five operating lever erfor = sary whose setting relatively slowly k is going on, since the desired motion and end position every3 the obsd to be adjusted items from the excavator operator = to be ignored, it while already the next adjustment operation with the assigned operating lever = initiates. A veratell movement is normally switched off by pushing the corresponding operating lever back into its neutral division.

The invention is based on the knowledge that adjustment = movements of all parts to be adjusted of an earth bea motion machine on the type of control stick for the flight = to operate tool guide.

1 Ü98 2 9 / 107Ö
BATH ORIGINAL

The object of the invention is therefore to provide a single tax = Provide lever and its adjustment movements to the particular ren sequence of movements of earthmoving machines, in particular Adjust shovel or backhoe excavators so that the excavator operator is able to make the desired adjustment = to simulate the movement of each of the parts to be adjusted with the control lever and their end positions already in To have an eye.

This object is achieved according to the invention in that the hydraulic pivoting, lifting and tilting cylinders have their own Pilot valves are assigned, but at the same time are electrically-hydraulically switchable independently of one another by a single multi-part control lever, which in as many degrees of freedom is pivotable and translationally displaceable as the lifting linkage and the work = tool can be moved, and that the control lever is the carrier of as many electrical setpoint transmitters, by actuating the control lever analogous to the movements of the lifting rod and the working tool can be set and an electrical circuit assigned to each setpoint generator is the downstream pilot valve operated until the position simulated by the control lever for each of the parts of the lifting rod and the work Tool is reached.

This ensures that the pressurized oil to act on the various hydraulic cylinders through the Pilot valves can be done simultaneously if this is the level of the available fluid pressure permitted. The simultaneous adjustment of several parts using the single control lever speeds up the verse ■ sharing of lifting rod and working tool. Further it is achieved that the excavator operator only focuses on the sequence of movements of the parts and adjusting su

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needs to concentrate on reaching its end position, since he always has all parts with his arm and hand control lever. The final shutdown of the adjustment movement of each part can be waited for without that part of the control lever in a neutral position to = must be moved back.

In addition, the control device according to the invention works almost free of inertia, since the electric-hydraulic control, the circuits assigned to the parts of the control lever respond immediately and no mechanical control Exercise losses can arise. The adjustment movement of the parts of the lifting rod and the working tool can can also be readjusted in one sense or another during steepening, if the one specified by the excavator operator simulated setting on the control lever should deviate from the actual situation.

Using an exemplary embodiment, the invention is shown in the drawing and in more detail below he = purifies; shows in the drawing

Fig. 1 in a perspective view to a tractor attached to one end of the shovel excavator,

Fig. 2 in a side view from the rear, the Aus = design of a valve manifold below the control stand,

3 shows the parts in a perspective illustration the control lever in the laid position,

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Fig. 4 is a partially schematic representation of the electro-hydraulic circuit for actuating the pilot valve for vertical Ver = Swiveling of the 3 extension arm,

Fig. 5 is an electrical circuit diagram of the electrical

Bridge circuit for modulating solenoid

Valves for controlling the pilot valve according to FIG. 4,

6 shows a schematic representation of a modified electro-hydraulic circuit for the position control of the lifting rod,

7 shows the electrical circuit diagram of a modified bridge circuit for the position control of the cantilever arm according to FIG. 6,

Fig. 8 is a plan view of the articulation of the boom ^ arm on the tractor and on the control lever,

9 shows a detailed view of a bearing housing for receiving the control lever,

10 shows an electrical circuit diagram for switching the pilot valve for hydraulic actuation of the mare's legs.

In the exemplary embodiment, the control device according to the invention is provided at the operator's station 13 of a tractor 10, at the rear of which an excavator, for example a shovel or shovel excavator on the ground, is arranged "bar ".

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The control device is operated by means of a single one arranged directly next to the driver's seat 11 Control lever 35, with which all functions of the excavator tools can be carried out.

The shovel excavator on which the exemplary embodiment is based consists in the usual manner of one on one of the end faces of the tractor 10 attached bearing plate 12, on which by means of a hydraulic motor 15 disengageable support = legs 14 are articulated, of which only one support leg is shown in Fig. 1, and the tractor with the Excavator bucket on the ground during excavation operation anchor.

Two spaced one above the other on the bearing plate 12 = flanged brackets 16 protruding laterally outward take a hydraulic motor 30 between them in a rotationally fixed manner and in aligned bores on its drive shaft, with which a vertical pivot bearing 17 for the cantilever arm 18 articulated thereon about a horizontal pivot axis. On the other end of the cantilever arm 13, the handle 19 carrying the show = fei 20 is articulated in a known manner. Extension arm, stick and Buckets are controlled in their movements by hydraulic cylinders 21, 22, 23.

As Fig. 2 shows, below the control 3 = Stand 13 a battery 62 of six valves 6l for cone = ble acting on the hydraulic motor 30 and the Hydraulic cylinders 15, 21, 22 and 23 with pressure oil. There are connections 63 at the respective ends of the valve cluster 62 provided on one side via an inlet line * device 67 supply the valves 61 with pressure oil and on the other side via a return line 79 a connection to the collecting container S.

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The electro-hydraulic control circuit:

Figs. 4 and 5 illustrate the control of one of the Valves 61 for applying, for example, the hydraulic cylinder 21 with pressure oil, which the boom 18 should operate.

A pump P supplies as shown in FIG. 4 via the inlet line 67 and - according to FIG. 2 - via one of the connections 63 one of the valves 6l of the valve cluster 62 pressurized oil in the piston chamber 68 of the valve 6l, from where the pressure oil in the neutral position of the valve via the return line 79 flows back into the collecting container S.

If the valve piston 70 is shifted to the right or left in the valve, the pressurized oil no longer flows to the without pressure Collecting container back, but gets to the via control edges of the valve piston and annular spaces of the valve body one or the other inlet side of the hydraulic cylinder. A pressure channel 69 inside the valve body serves for this purpose pers and two outlets 72, 73 on valve 61.

If, for example, the boom 80 is to be lowered, the hydraulic cylinder 21 is extended by shifting the valve piston 70 to the right, whereby pressure oil from the line 67 passes through the pressure channel 69 into the control groove 8l, from where the pressure oil opens the valve at the outlet 72 leaves via the connecting line 76 to the cylinder 21. The displaced by the piston of the cylinder 21 flow sigkeit escapes via the other connection line 77 'to the second terminal 73, the control groove 83 and the connection via a return line 79 to the sump S in verse stationary channel 78 sun Sann flasks S.

109Ö29 / 1078

If the boom 18 is to be raised, the valve = piston 70 must be moved to the left, whereby the Reverse flow directions accordingly.

The displacement of the valve piston 70 in one direction or the other is actuated hydraulically Servomotor 85 controlled, which is housed in a housing 86 connected to the valve 61 and consists of a on an extension of the valve piston 70 is firmly arranged piston slide 87, which is through inlets

88 or 89 is acted upon _{with pressurized oil from a pump P 1} either on one side or on the other. This piston valve is switched over via two solenoid valves 110, 111, the inputs of which are connected in _{parallel with the outlet of the pump P 1} and the outputs of which are connected via lines 114, 115 to the inlets 88 and

89 are connected. The three-way solenoid valves 110, 111 normally connect channel 113 on the pressure side of pump P ₁ to lines 114 and 115, but can be individually connected electrically so that they _{displace the pressure side of pump P 1} and that of spool valve 87 Connect pressurized oil to the collecting container S via the solenoid valve that is actuated.

The electrical actuation of the solenoid valves 110 is provided by a bridge circuit, as best shown in FIG Fig. 5 is reproduced.

The bridge equilibrium is always reached and indicated by a zero indicator 109 when the Partial voltages tapped from the two variable resistors 44, 92 at sliding contacts, one to the variable resistors and the zero indicator in parallel connection = the supply voltage of an electric battery

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are · starting from a given position example = way of the cantilever arm 18, which is to be brought into a new starirnte raised or lowered position, the bridge equilibrium is disturbed or the bridge current to one or the other of the two Solenoid valves applied by the sliding contact of a variable resistor 44 with a horizontal The pivot axis of a hand lever 46 of the control lever 35 is coupled and the sliding contact of the other Hegel » Resistance 92 is actuated by one end of the valve piston 70. So the hand lever 46 is up or pivoted down, the tap on the variable resistor 44 is adjusted and there is a bridge equation = Weight a different voltage, which, depending on polarity, actuates the solenoid valve 110 or 111 and switches in such a way that that the piston slide 87 moves the valve piston 70 in one direction or the other and the hydraulic = The cylinder 21 looks in or disengages, until the tapped at the control resistor 92 is reached, with the rule " resistance 44 given partial voltage equals the bridge = weight is restored and the extension arm 18 has reached the desired lifting position «

The Regelwideretand 92 is arranged with its sliding contact at the end of the valve piston 70 such that the The photentiometer housing is fixed to the system, for example attached to a tab 93 on the control station 13 in a rotationally fixed manner and the sliding contact via a lever 94 with an am End of the valve piston 70 laterally protruding bolt 95 is pivotable »

The solenoid valves 110, 111 respond to such Poia = linearities in that the cantilever arm 18 in the same direction of rotation is moved up or down, as the movement of the hand lever 46 of the control lever 35 manually faked

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will. The excavator operator thus always has a control over the correctness of the direction of rotation in which he has his arm the hand lever 46 puts on and angled it when the Aus = laid arm 18 is raised or angled it when the Aus = casual arm 18 is to be lowered. The excavator operator simu = So with his arm, the movement of the boom arm is to be executed,

An electro-hydraulic control device described in the embodiment according to FIGS. 4 and 5 can now provided for each of the actuating devices 15 »30, 21, 22 and 23 or to act on the associated valves 61 be.

Execution of the control lever:

Every; This electro-hydraulic control device is now operated by the same control lever 35, by means of which the four movements required when operating an excavator - namely pivoting the boom in a horizontal plane, pivoting the boom in a vertical plane, pivoting the handle and tilting the shovel - Can be simulated by appropriate movements of the control lever 35. The corresponding movements on the control lever 35 in the same order are therefore turning the hand lever 46 in a horizontal plane around a vertical axis, turning the hand lever 46 in a vertical plane around a horizontal axis, a translational movement forwards or backwards in the The sense of how the shovel should move forwards or backwards through the handle, and turning a handle 54 on the hand lever 46 in the same way as the excavator shovel is tilted , is great.

109829/1078

In detail, it can be seen from Fig. 3, how the tax = lever 35 composed.

The hand lever 46 is supported by a vertical support 36 which, as shown in FIG. 9, is rotatable in a housing 57 is stored. At the lower end of the support 36, a gear 38 meshes with a pinion 39, the axis of which is inside of the housing 57 with the sliding contact of a potentiometer 40 is in rotary connection, which one of the two control resistances of a bridge forms, which for the rotary movements of the boom 18 around the verti = kale drive shaft 31 of the hydraulic motor 30 for the pivot bearing 17 is responsible.

The support 36 runs out at its upper end in a fork 37, one end of the hand lever 46 so = as another fork 41 by means of a bolt 53 = takes between its ends in mutually curse border bores 45. The fork 41 is firmly connected to the hand lever 46 by means of bores which are not shown in the drawing and which are arranged diagonally to the bores 45. The fork 41 has a downward extension with a bore through which the shaft of a botentiometer 44 connected to the fork 41 is guided and connected to a pinion 43 which meshes with a curved rack 42 which in turn is firmly connected in the lower region of the fork 37. Therefore, if the hand lever 46 is pivoted in a vertical plane, the pinion 43 executes a pivoting movement with respect to the bolt 53 and is rotated by the engagement of its teeth in the teeth of the non-rotatably arranged rack 42 itself, so that a pivoting movement of the hand lever in the vertical plane to an analogous rotary movement of the pinion 43 and to an analogous adjustment of the sole contact in the potentiometer

10β020 / 107β

44 leads. The potentiometer 44 receives the input function of the bridge 109 shown in FIGS. 4 and 5 for lowering and lifting the boom 18.

The hand lever 46 consists of an inner part 48 and an outer cranked part 47, which over the inner vertically fixed part 48 can be telescoped forward and backward. This shift = Movement can be electrically operated by a potentiometer 49 connected to the outer part 47 via a bracket 50 remove by inserting the potentiometer shaft through a hole in the bracket 50 and using a pinion 51 Is rotatably connected, which is provided with a provided on the inner part of the hand lever 46, along the lower edge extending rack 52 can be rotated. The potentiometer 49 is part of a bridge that over a valve 6l regulates the extension of the hydraulic cylinder 22 controlling the excavator stick 19.

Finally, the handle 54 is mounted rotatably about an axis extending perpendicular to the hand lever 46 at the end of the outer part 47. A bolt 55 non-rotatably connected to the handle 54 rotates the potentiometer shaft of a potentiometer 56 which is fixedly attached to the end of the hand lever 46 and which is part of a bridge that extends the hydraulic cylinder 23 via a valve 61, causing the excavator shovel 20 to tilt regulates.

Attitude controlι

for example, manually operated pivoting movements of the control lever 35 in the horizontal plane in ana = Let swivel movements of the boom 18 to implement the shaft 31 driven by the hydraulic motor 30,

109829 / 107Ö

is based on FIGS. 6 and 7, the electro-hydraulic Control device for the hydraulic motor described in a modified embodiment in which the setpoint value achieved by the setting potentiometer 40 by means of the actual value from the drive shaft 31 = target actual position is compared. The electro-hydraulic circuit is essentially the same as that of the Fig. 4 coincides.

In addition, however, at one end of the drive shaft 31 on one of the consoles 16 there is a potentiometer 131 ans flanged, the shaft of which is non-rotatably connected to the drive shaft 31 of the hydraulic motor 30. As 7 shows that the potentiometer 131 is connected in parallel to the manually operable potentiometer 40, However, the direction of rotation of the two potentiometer taps is so opposite to the effect that one Rising partial voltage at potentiometer 40 results in a drop in the partial voltage at potentiometer 131 has when the drive shaft 31 by the hydraulic Motor 30 is rotated. The zero indicator 109 therefore only registers voltage differences between the part = voltages of potentiometers 40 and 131 · If the control lever 35 is therefore moved to the right, the Sliding contact according to FIG. 7 increasingly from a smaller partial voltage on potentiometer 40, so that the zero indicator registers a control of the bridge and the solenoid valve 111 actuated to the valve piston 70 in the plane of the drawing 6 to the right or in the drawing plane of FIG. 7 downwards. This shift takes the Potentiometer shaft of the potentiometer »92 accordingly and takes a partial voltage in the sense of how this is indicated in Fig. 7 in dashed lines.

10982 9/107

At the same moment the valve 61 is switched so that the hydraulic motor 30 drives the drive shaft 31 clockwise = gerainn adjusted what by the sliding contact of the pot = tiometer 131 is controlled, since with increasing Yer = position clockwise a rising partial voltage is tapped, which is set together with the smaller = th partial voltage of the potentiometer 40 approaches a value which again corresponds to the bridge equilibrium, so that when the bridge equilibrium is reached, the sole = noid valve 110 is actuated to release the valve piston 70 to bring back into neutral position after the ge = desired position of the cantilever arm 18 in the horizontal plane has been achieved.

As can be seen from Fig. 8, a movement of the control = hebeis 35 in the horizontal plane by an angle ot one equal angular movement of the cantilever arm 18 result, so that by an analog control of the boom after a setting of the control lever specified by the excavator operator can be.

9 shows the non-rotatable mounting of the housing 57 receiving the fork 37 at a point that is fixed to the system the control station 13. At the upper edge of the housing 57 holes 58 are axially in the housing wall = let, can be used in the stop pins 59 = NEN to the working width of the boom 18 in hori = To delimit the zontal plane, within which, for example, a trench of a certain width by means of the shovel 20 should be excavated. The excavator operator no longer needs to rely on markings on the ground. which he otherwise has to pull beforehand, but he only moves the control lever 35 within the by = impact pins 59 limited angular range.

109829/1078

Pig. 10 illustrates the particular control means for the hydraulic motor 15 down from = Movable support legs 14. Since a continuous adjustment is not necessary, the two outer = Most of the valves of the valve cluster 62 are not provided with potentiometers and the associated solenoid valves can only be actuated by off switches 120, 121.

Patent claims:

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Claims (10)

- Io - Claims 1, "control device for the working tools of Erdbe = ^" wegungsmaschinen, especially bucket or shovel, with hydrau in at least one plane = lisch pivotable Aushebegestänge and hydraulically tiltable work tool, characterized in that the hydraulic pivoting, lifting and tipping cylinders ( 30, 21, 22, 23) their own pilot valves (61) are arranged, which at the same time, but independently of one another, can be electrically-hydraulically switched by a single multi-part control lever (35), which can be pivoted and translated in so many degrees of freedom is displaceable, as the lifting linkage (18, 19) and the working tool (20) can be moved, and that the control lever (35) is the carrier of as many electrical setpoint transmitters (40, 44, 49, 56), which can be activated by actuating the The control lever (35) can be adjusted analogously to the movements of the lifting rod and the working = tool and an electrical circuit assigned to each setpoint generator according to the ordered pilot valve 6l operated until the position simulated by the control lever (35) of each of the parts of the lifting rod and the working tool is reached, 2. Control device according to claim 1, characterized in = shows that the control lever (35) consists essentially of a hand lever (46) and a handle (54) consists, of which by means of the hand lever (46) the movements of the lifting rod and by means of the hand = handle (54) the movement of the working tool ana = log can be simulated 109829/1078 3. Control device according to claim 1, characterized in that with the movable parts of each Vorateuerventils (61) an electrical actual value transmitter (92) is coupled "and the pilot valves (61) by comparing the voltage between the associated voltage of the setpoint generator (40, 44, 49, 56) and the actual value encoder (92) can be operated 4 · Control device according to claim 3, characterized in that = shows that the electrical setpoint generator systems potentiometers (40, 44, 49t 56) that are firmly attached to the parts of the control lever (35), the potentiometers of which are * meter by meter of each part of the control lever (35) are adjustable, the movement of the respective Pretend lifting linkage or the work tool that the voltage comparison in one with the electric see actual value sensors (92) connected electrical bridge circuit can be carried out, and that one occurring at a zero indicator (109) corresponds to a deviation from the bridge equilibrium corresponding control voltage is supplied to solenoid valves (110, 111), which hydraulically control the respective active pilot valve (61) in the preselected flow direction to the high pressure side a pressure oil pump (P) until the Control lever (35) predetermined target position from the "lifting linkage" or "from the work tool and the elec" Trisehe equilibrium of the associated bridge is reached are· 5, control device according to claims 3 and 4, characterized characterized in that the each pre-control valve (61) assigned actual value transmitter (92) from a valve piston (70) of the Voriteuer valve (61) can be actuated, and the valve piston (70) by one of the solenoid 109829 / 1Ü7 8 Piston slide (87) controlled by valves (110, 111) in one neutral position and in two opposite positions Passage directions for the application of one or the other side of the hydraulic pivoting, lifting and tilt cylinder (30, 21, 22, 23) is displaceable, 6, control device according to claim 5, characterized in that, when the bridge is in equilibrium, both solenoid valves (110, 111) divert pressure oil from a pump (P ₁ ) to the tank (S), and that depending on the polarity of the control span deviating from the bridge equilibrium = tion one or the other solenoid valve (110 or 111) connects the pressure side of the pump (P ₁ ) with a piston chamber that moves the piston valve (87) either to the right or to the left via inlets (88 or, 89). 7 · Control device according to claim 2, characterized in = shows that the parts of the control lever (35) can be pivoted, displaced and rotated about the same axes = are bar, like the parts of the lifting rod and the work tool pivotable, displaceable and are rotatable 8 · Control device according to claim 7, characterized in that the hand lever (46) is pivotable about a vertical and a horizontal pivot axis (36, 53) and with the potentiometer shafts assigned to these pivot axes the potentiometer (40, 44) of the respective Target value for the application of the hydraulic motor (30) for swiveling the boom arm (18) about a vertical swivel axis (position = control) and for the application of the hydraulic cylinder (21) for swiveling the boom arm (18) is adjustable about a horizontal swivel axis 109829/1078 . _19th 2061175 9. Control device according to claim 7, characterized = shows that the hand lever (46) is made out of two parts and an inner part (48) is telescopic is received by an outer part (47), when it is longitudinally displaced with respect to the inner part (48) by means of the potentiometer shaft of a potentiometer (49) the target value for the movement of the das Working tool (20) carrying, at the upper end of the extension arm (18) articulated handle (19) adjust = is cash 10. Control device according to claim 7 »characterized = records that the handle (54) rotates about a transverse to the hand lever (46) extending horizontal axis = bar and by means of the potentiometer shaft of a potentiometer (56) assigned to this axis of rotation, the setpoint value for tilting the work tool, e.g. an excavator shovel (20), is adjustable 11, control device according to claims 8 to 10, da = characterized in that the potentiometer shafts of the potentiometers (40, 44, 49) rotatably with pinions (39, 43, 51) are connected, each of which meshes with a toothed wheel (38) or a toothed rack (42, 52), which is arranged on the part which is fixed to the system with respect to the respectively actuated part of the control lever (35) are, 12 «Control device according to claims 3, 4 and 8, characterized in that an additional actual value transmitter (131) in the form of a potentiometer is coupled to the drive shaft (31) of the hydraulic motor (30), and that the electrical sum the tapped from these potentiometers and the partial voltage from the manually operable potentiometer (HO) 109823/1078 the set partial voltage in the bridge circuit and the control voltage obtained from it depending on their polarity, one or the other solenoid valve (110, 111) is actuated until Bridge equilibrium between the total voltage and the actual value tapped on the potentiometer (92) is reached, 13 · Control device according to claim 8, characterized in that the vertical pivot axis (36) of the Control lever (35) is mounted in a housing (57) arranged on the operating stand (13) and the hand lever (46) in its horizontal pivot = movement through the stop projecting from the housing (57) pins (59) is limited. 1 09829/1078 Blank page