SU1797757A1 - Arrangement for swinging reversible plough shaft - Google Patents

Description

The invention relates to agricultural machinery, in particular to reversible plows.

The purpose of the invention is to reduce unproductive power losses and increase the reliability of the device.

The drawing shows the inventive device for rotating the shaft of the reversible plow.

The proposed device for rotating the shaft 1 of the reversible plow 2 includes two hydraulic cylinders 3 and 4, which are symmetrically located relative to the longitudinal vertical plane 5. passing through the axis of the shaft. Hydraulic cylinders 3 and 4 are single acting. They can be of the plunger type or have two cavities - a piston and a rod (as shown in the drawing), but in this case the rod cavities are not involved. Piston cavities 6 and 7, respectively, of hydraulic cylinders 3 and 4 are connected by lines 8 and 9 through a distributor 10 with a pressure line 11 and a drain tank 12. Each of the lines 8, 9 of the piston cavities 6.7 is also connected to the hydraulic tank 12 via side branches 13, 14 In each of the side branches 13, 14 identical pressure valves 15.16 are installed. It is possible to control the opening pressure of said pressure valves. This allows you to optimize the braking process of the plow frame in the final phase of rotation. Naturally, the pressure of opening pressure valves is greater than its operating level in the rotation phase with a positive load (otherwise this rotation phase is from 0 to 90 °, when the hydraulic cylinder develops torque against the load created by the mass of the plow, it becomes simply impossible).

The plow 2 has a mass G, the reduction point of which is indicated by 17. During the rotation of the plow, the center of mass 17 of the displacement

is semicircle 18 (above the axis of the rotation shaft). In the drawing, the plow frame 2 is conventionally shown in the initial position.

In the case of a distributor with a closed center, as shown in the drawing, the pump 19 is equipped with a mechanism 20 for its unloading at idle.

A device for rotating the shaft of a reversible plow works as follows.

If necessary, turn the plow, for example, to change the right-turning plow bodies to left-turning ones and vice versa (plow bodies are not shown conventionally in the drawing), the distributor 10 is installed in one of the working positions (in the drawing, the distributor is shown in one of the working positions), and the oil flow by the pump is pumped into the working cavity of one of the cylinders, in this case, into the working cavity 7 of the hydraulic cylinder 4 along line 9. The second hydraulic cylinder 3 plays a passive role, since its piston cavity 6 is connected by a line 8 to the hydraulic tank 12, and the rod (if any) is in communication with the atmosphere. The rotation phase from 0 to 90 ° is carried out in the conditions of oncoming load. Subsequently, the plow falls under the action of its mass G. The dead position of the hydraulic cylinder passes by inertia, which it manages to gain when the shaft rotates from 90 ° to the moment when the hydraulic cylinder falls into a dead position. After passing the dead position, the piston of the hydraulic cylinder 4 begins to move in the opposite direction, i.e. towards the flow of injected fluid. The pressure in the cavity 7 rises to the level of adjustment of the corresponding pressure valve 16. The hydraulic cylinder 4 begins to work as a brake. In this case, immediately after the hydraulic cylinder passes through the dead position, the braking moment is small, because there is little shoulder on which the force of the rod of the hydraulic cylinder in question acts. This is good, since the plow freezes when the hydraulic cylinder passes through the dead position. As we approach the end of rotation, the braking moment of hydraulic cylinder 4 increases (due to shoulder growth, the force remains constant, because the pressure in the piston cavity is constant at a given pressure valve setting), which corresponds to an increase in the turning moment created by the mass of the plow G. Corresponding By adjusting the pressure valves (or by changing the height of the articulated suspension of the hydraulic cylinders), soft, shockless completion of the rotation of the plow shaft can be achieved.

The entire rotation cycle - from Odo 180 ° ^ takes place when the distributor is in the same working position.

To make the rotation in the opposite direction, the distributor 10 is set to a different operating position. The rotation process is carried out as described above, but the hydraulic cylinder 3 becomes a worker, and the hydraulic cylinder 4 is assigned a passive role.

The use of the proposed device for turning the shaft of the reversible plow allows you to increase efficiency by eliminating unproductive losses of hydraulic energy And extend the service life due to the optimization of the braking phase.

Claims (1)

Claim A device for turning the shaft of a reversible plow, comprising two hydraulic cylinders located symmetrically with respect to the longitudinal vertical plane passing through the axis of rotation of the shaft, the rods of which are pivotally connected to the end of the crank shaft, and the piston cavity of each of them is connected with the tractor hydraulic system via the hydraulic line through the last a distributor, characterized in that, in order to reduce unproductive power losses and increase reliability in operation, it is equipped with two auxiliary hydraulic lines, each of which I am made in the form of branches connected by a retaining valve to the hydraulic system tank of the tractor from the executive line of the piston cavity of the corresponding hydraulic cylinder, each hydraulic cylinder being made in the form of a single-acting engine.