DE2424018A1 - INDEPENDENT LEVELING DEVICE FOR LARGE AGRICULTURAL MACHINERY - Google Patents

Description

PATENT LAWYERS

DIETRICH LEWINSKY

HEINZ-JOACHIM HU3EK ¹ I * ^{May 1} ^ ⁴

REINER PRIETSCH 7937-IV / K

White Farm Equipment Company, Wilmington, Delaware (V.St.A.)

"Automatic level control device for large agricultural Machinery"

Priority dated May 18, 1973 from the Italian patent application 46852 A / 73

The invention relates to an automatic level control device for large agricultural machines, for example harvesting machines.

Agricultural prime movers are coming on a large scale at present such as combine harvesters and the like, which are mounted on a self-propelled vehicle, the enables direct operation in the field from which the product is to be harvested.

Because of their complex structure, these machines are always proportionate big and heavy and since they should be able to be used on a wide variety of surfaces, one of the problems is which require the greatest attention in their construction, that of the design of the vehicle carrying the machine; witnesses. In particular, the vehicle must often move on a surface whose inclination is both in the longitudinal direction as well as the transverse direction of the machine changes, so that it is: Often extremely important, the vehicle with an automatic Equip level control device. Its purpose is

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to reduce the overall ground clearance of the machine in order to reduce the Increase safety and improve the overall properties of the machine.

The invention is based on the object of providing an automatic level control device of the type specified in the introduction create that meets the aforementioned conditions, simply structured and an economical series production is allowed.

This object is achieved according to the invention in that the machine body is connected to a self-propelled chassis via articulated connections and piston-cylinder arrangements controlled by solenoid valves allow an inclination of the machine body relative to the chassis both in the longitudinal and in the transverse direction and that the solenoid valves are output by level sensors arranged in the longitudinal direction and in the transverse direction of the machine and electrically processed signals are controllable.

According to the invention, the machine body is on a four-wheel chassis articulated and can both by actuating suitable piston-cylinder arrangements in relation to the chassis be inclined in the longitudinal direction as well as in the transverse direction. The operation of the piston-cylinder arrangements is controlled through a processing circuit for a signal coming from appropriate Level sensors is generated in such a way that every time the machine is on one side against the horizontal tends to operate the piston-cylinder arrangements in such a way that the machine body is returned to the horizontal position while the vehicle can continue to move forward with maximum grip.

According to an advantageous embodiment, the level sensor consist, for example, of two elements of variable capacity inserted into an equal number of vessels,

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which are arranged on the sides of the machine at the same height.

These vessels contain a suitable liquid and are interrelated connected by a connecting line. A pair of vessels is arranged between the side surfaces of the machine body, so that it detects any deviation in the transverse direction, and a second pair of vessels is between the front end ; and the rear end arranged so that there is any deviation in the

■ Determines the longitudinal direction.

; As will be explained, every variable capacity

; before element connected to an electronic circuit that

I in turn controls the operation of the solenoid valves that control the

Control \ ben cylinder arrangements for level adjustment.

Furthermore, according to the invention, the vehicle is the machine

! able to control the axis of rotation of the drive wheels. tend to so

j the drive wheels in a vertical plane even with sideways

i hold on sloping ground. In addition, the level setting

! treatment for the machine body in the longitudinal direction combined with

^! raising or lowering the front mower

^{: control} , so that the mowing gate is always in the

! the same distance from the ground.

; In the drawing, the level control device according to the acquisition \ is an invention based, for example, the selected embodiment

■ illustrated schematically. Show it:

I -

I Figure 1 is a side view of the machine,

; Figure 2 is a plan view of the articulated chassis of the machine, FIG. 3 shows a front view of the machine with particular emphasis

Consideration of the articulated bearing chassis,

: Figure 4 is a diagram of the hydraulic circuit of the level control ; device in the transverse direction,

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Figure 5 is a diagram of the hydraulic circuit for the adjustment device in the longitudinal direction and Figure 6 is a circuit diagram of the electrical and electronic

Control circuit for each of the two setting ι Devices is provided. |

As can be seen from the figures, the machine essentially consists of I borrowed from an upper body or machine body 1 on which! At the front there is a driver's compartment 2. !

The machine body 1 is rigid in its lower area with profile longitudinal members 3 and 4, a rear cross member 5 and j two triangular plates 6 and 7 arranged at the front are connected!

the. ·!

The two triangular plates 6 and 7 are in their upper area in the middle of a first pivot 8 and in the lower A second pivot 9 traverses the area in the middle. On the first pivot pin 8 sits over a between the j two plates 6 and 7 arranged U-member 11 rotatable an upper one j Cross member Io of the front end. A lower cross member 12 of the front end of the machine is also pivotably seated on the second pivot pin 9 via a triangular bearing 13, which is also accommodated between the plates 6 and 7.

The two parallel cross members Io and 12 are at their ends articulated to the wheel carriers or hubs 14 and 15 of the front wheels 16 and 17 of the machine. At the top of the page the plates 6 and 7 branch off two spreader arms 18 and 19 and carry two rotatable forks 2o and 21 at their upper ends, in which the jacket tubes of two piston-cylinder assemblies 22 and 23 are mounted.

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The piston rod of the piston-cylinder arrangement 22 is articulated to a bearing 2H at the right end of the upper cross member Io of the front end and the piston rod of the piston-cylinder arrangement 23 is connected to a corresponding bearing 25 at the left end of the upper cross member Io.

The arrangement described above forms an articulated, symmetrical front end, in which when the piston rods of the two piston-cylinder assemblies 22 and 23 are of equal length, the center of gravity of the upper or machine body 1 exactly above the center line of the wheel base or wheel contact area the wheels l6 and 17 is located. When the vehicle is tilted at a certain angle in the lateral direction Moving underground, it is possible to move the body 1 by changing the ratio of the lengths of the two piston rods 22 and 23 to be brought back into an exactly horizontal position. At the same time, because of the articulated connection, the cross member Io and 12 with the triangular plates 6 and 7 represent the central plane of the front wheels 16 and 17 held vertically. i

j These compensatory movements are monitored by level sensors in connection

suitable electronic processing and control equipment, which will be described later,

; controls.

With the rear end of the lower fixed chassis of the machine is a trapezoidal beam 26 with a rear Port set 27 rotatably connected, of which a cantilevered, j casual-like pivot pin 28 goes off. A cross member 29 'is rotatably seated on this pivot pin 28 at the ends of which the wheel carriers I or hubs of the controllable rear wheels 3o and 31 are mounted.

The trapezoidal support 26 is with the fixed chassis of the machine also articulated via the piston-cylinder arrangement 32

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connected, the piston rod pivotable on the cross member 33 and the cylinder or jacket tube pivotable in a fork seated on the rear cross member 5 of the fixed frame of the machine.

In this way it is by actuating the piston-cylinder arrangement 32 possible to change the storage or suspension height of the rear part of the machine and thereby make changes to compensate in the slope of the ground in the longitudinal direction of the machine.

These compensating movements are followed by corresponding movements of the front mowing device 35 in the vertical, the pivotable by side arms 36 with the fixed chassis of the machine connected and adjustable in height by a piston-cylinder arrangement 38.

For example, when the machine is going uphill, the rear piston-cylinder arrangement 32 lowers the rear wheels 3o and 31, to keep the body 1 horizontal. At the same time, the front piston-cylinder arrangement 38 lifts the mowing device 35, to keep them at the required distance from the ground. The reverse process takes place when the machine is going downhill is working.

To achieve the adjustment operations described above, the piston-cylinder units 32 and 38 are connected to a hydraulic system, which is illustrated in the diagram in Figure 5 and -th their Arbei- is controlled by an electronic circuit, which in | Figure 6 is reproduced.

The hydraulic circuit of Figure 5 begins with the pump 39 > is connected via a line 4o to a solenoid valve 41 with three positions. A first line 42 connects an outlet of this valve to the J rear working chamber

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Piston-cylinder arrangement 32. The front working chamber of this arrangement 32 is connected via a line 43 to the rear working chamber of the piston-cylinder arrangement 38, the front working chamber of which is connected to the solenoid valve 41 via line 44. The solenoid valve 41 is finally through the; Line 45 is connected to a liquid container 46. On ; In this way, the piston-cylinder arrangements 32 and 38 are connected in series with respect to the inflow or pressure line of the pump 39. In the middle position of the three positions of the solenoid valve 41, no liquid flows in the hydraulic circuit connecting the arrangements 32 and 38. This is also the rest position of the valve 4l. In its two other positions, the distributor body of the valve 41 is through ^; Applying the two control coils or windings 47 and 48 brought to voltage.

When winding 47 is energized, it is from the pump

incoming line 40 with line 42 to the piston-cylinder j

Arrangement 32 and the line 44 with the line 45 to the river j

fluid container 46 connected. I.

In this way, the piston and cylinder assembly 32 increases the suspension height or ground clearance of the rear end of the body 1 and the assembly 38 simultaneously lifts the mower gate 35 to keep it in alignment with the position of the machine wheels.

This correction is necessary when the machine is going uphill. If the machine is going downhill, it will be the correct setting achieved by applying the second winding 48 of the solenoid valve 41 to voltage. In this position the distributor body connects of the solenoid valve 4l, the line 4o coming from the pump with the line 44 to the piston-cylinder arrangement 38 and

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the line 45 leading to the liquid container 46 with the line 42 to the piston-cylinder arrangement 32 the ground clearance of the rear end of the machine body 1 is reduced and the mowing device 35 is lowered accordingly.

As already stated, these height corrections have to be figured out, ' that the machine body 1 is always kept in a horizontal position and the corrections must therefore be ended, when the body has reached the required position. This is achieved by the level sensor for the longitudinal direction, which is made from two vessels 49 and 5o, which are connected by a line 51 and contain liquid to an appropriate level. Your arrangement is made so that in horizontal Position located body 1, the liquid in the two vessels reaches the same level. Any positional deviation of the body 1 in the longitudinal direction produces a rise in the liquid level in one of the two vessels 49 »50. In these Vessels 49 and 5o are the electrodes of the corresponding capacitance variable Elements 52 and 53 introduced, which work intermittently, depending on whether the contained in the demjaefäß Liquid touches the electrodes of these elements f. Or not.

Each of the elements 52 and 53 is connected to a control circuit similar to that shown in FIG Coil of the solenoid valve 41 is supplied. Figure 6 particularly shows the circuit that operates when the machine is goes downhill.

if
/ the level sensor 52 is touched by the liquid, it triggers the coil 48; The level sensor 53 operates in the same way on the coil 47.

The process obviously continues as long as the electrodes of the level sensors 52 and 53 are wetted by the liquid;

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that is, until the body 1 is returned to a horizontal position in the longitudinal direction.

In the electronic processing and control circuit according to. In FIG. 6, the level sensor 52, that is to say the variable-capacitance element, influences the state of an oscillator transistor 54, whose signal is rectified by the diode 55 and controls two transistors 56 and 57, which act as switches for the Current through a coil 58 act.

j when current flows through relay coil 58 includes a contact 59, j of the corresponding coil 58 of the solenoid valve ¹ sets of clamping Jl-I voltage, j are actuated whereby the piston-cylinder assemblies 32 and 38th

j for each of the variable capacitance elements 52 and 53 is j one of these circuits is provided to the corresponding coil

: to control the solenoid valve.

i From the preceding description it can already be seen that

! the machine with a second analog device for the

! automatic level control in the transverse direction

I can be.

For this purpose, the piston-cylinder arrangements 22 and 23 of the j front end according to the diagram in Figure 4 hydraulic! connected with each other:.

The pump 6o is via a line 61 with a four-way solenoid valve 62 connected with three positions analogous to the valve 41 for level control in the longitudinal direction. The solenoid valve 62 in turn comprises two control coils or control windings 63 and 64 and a second line 65 which into a liquid container 66 immersed.

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Two lines 67 and 68 lead from the solenoid valve 62, one of which leads to the piston-cylinder arrangement 22 and the other to the piston-cylinder arrangement 23. Both lines are each connected to the same end of the corresponding piston-cylinder arrangement. The two connections of each piston-cylinder arrangement are cross-connected via two lines 69 and 7o, so that the total connection of the two arrangements in the inflow line of the pump 60 is antisymmetrical. This type of connection means that when the coils 63 and 6k of the solenoid valve 62 are energized, the liquid in the circuit flows in the corresponding direction, so that when one of the two piston-cylinder arrangements is elongated, the other shortens. Conversely, when the other coil of the solenoid valve 62 is energized, the liquid flows in the opposite direction and the piston, which previously moved out of the cylinder, now moves into the cylinder, while the other moves out of its cylinder. In this way, the body 1 inclines in the required direction with respect to the inclination of the ground. Again, the fact that the correction is carried out until the body 1 is brought into the horizontal position again, the actuation of the piston-cylinder arrangements 22 and 23 is controlled by a level sensor, which this time is arranged in the transverse direction of the body 1. This level sensor consists of two vessels 71 and 72 (see FIG. 3) which are connected by a line 73 and contain a certain amount of liquid. As in the previous case, two variable-capacitance elements 74 and 75 project into these vessels, each of which controls a control circuit of the type shown in FIG. 6 in the same way as was previously described for the level control in the longitudinal direction.

Each of these circuits controls the application of voltage to one of the coils 63 and 64 of the solenoid valve 62 and the connections

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are chosen so that when the liquid wets one of the two variable capacity elements, the piston-cylinder arrangement, which is elongated, is the one that lies on the same side, so that the body 1 in the horizontal Location is returned.

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Claims (3)

.. 2424-18 May 17, 1974 7937-IV / K White Farm Equipment Company Claims: ι jl.i Automatic level control device for large agricultural 'borrowed machines, for example harvesting machines, characterized in that the machine body (1) is connected to a self-propelled ■ chassis via articulated connections and piston-cylinder controlled ^{via solenoid valves (e.g. 1 II, 62)} Arrangement | openings (22, 23, 32) allow an inclination of the machine body (1) relative to the chassis both in the longitudinal and in the transverse direction and that the solenoid valves by; In the longitudinal direction and in the transverse direction of the machine level sensors (52, 53; 74, 75) emitted and electrically processed signals can be controlled. : 2. Apparatus according to claim I _9, characterized in that the level sensor (52, 53; 74, 75) variable capacitance sensor with three _{electrodes arranged in a vertical vessel (49, 5o; 7I 9} 72) and one connecting the vessels in one direction, a conduit (51; 73) containing an appropriate amount of liquid and that each of the variable capacitance sensors is connected to an electronic processing circuit for actuating the corresponding solenoid valve each time the liquid contacts the sensor due to a change in position of the machine. 3. Apparatus according to claim 1 or 2, characterized in that the piston-cylinder arrangement (32) which the machine in With respect to the chassis, it rises in the longitudinal direction, in line with a piston-cylinder arrangement (38) that controls the mower (35) raises, lies, such that when lowering 409851/0721 -I- the rear wheels (3o, 31) the mower (35) lifts and vice versa, and the arrangement is designed so that the The cutting line of the mowing equipment remains aligned with the support surface of the front and rear wheels of the machine, 409851/0721 ty Blank page