HYDRAULIC UNIT WITH PARALLEL PUMPS LINKED TO A SERVOMOTOR AND USE THEREOF

Abstract

A hydraulic unit is provided that includes a ball screw, which is driven by a servomotor, and both are configured to raise and lower two hydraulic sleeves of two hydraulic piston pumps, mounted in parallel and separately from one another. This is to draw hydraulic oil from an oil reservoir and pump this pressurized oil into one or more hydraulic pressure accumulators. When the hydraulic pressure accumulators are full, there can be an increase in hydraulic pressure activating a pressure sensor that can control the halting of the servomotor.

Claims

1-9. (canceled)

10. A hydraulic unit with parallel pumps linked to the servomotor characterized by comprising: a first hydraulic pump comprising a hydraulic sleeve, an upper hydraulic chamber, a lower hydraulic chamber, a plunger, two hydraulic rods, a hydraulic pressure accumulator and a plunger; a second hydraulic pump comprising a hydraulic sleeve, an upper hydraulic chamber, a lower hydraulic chamber, a plunger, two hydraulic rods, a hydraulic pressure accumulator and a plunger; a servomotor, coupled to a roller bearing that has a ball screw coupled on the other face; a pressure sensor; a reservoir; an upper check valve; a lower check valve; a suction filter; wherein the two hydraulic pumps mounted in parallel work jointly with the servomotor; and wherein the ball screw has the function of displacing the bolt of the ball screw upwardly or downwardly, according to the rotation direction of the servomotor.

11. The hydraulic unit according to claim 10, characterized in that the hydraulic rods are static, fixed on the roller bearing and on a base.

12. The hydraulic unit according to claim 10, characterized in that the hydraulic sleeves of the hydraulic pumps move to perform the pumping.

13. The hydraulic unit according to claim 10, characterized in that optionally the hydraulic rods have different diameters producing four different pressures.

14. The hydraulic unit according to claim 10, characterized by working immersed in the oil.

15. The hydraulic unit according to claim 10, characterized in that the hydraulic pressure accumulators act as an element for guaranteeing the continuous supply of oil to eliminate interruption of the oil flow during the reversal of the movement.

16. The hydraulic unit according to claim 10, characterized in that it is for moving the hydraulic actuators that operate with hydraulic oil.

17. The hydraulic unit according to claim 16, characterized in that up to 90% of the volume of oil from the reservoir is reduced.

18. The hydraulic unit according to claim 17, characterized by generating savings of up to 90% in electric energy.

Description

DESCRIPTION OF THE DRAWINGS

[0033] The invention will now be described in terms of an embodiment, and for improved understanding, references will be made to the accompanying drawings, in which the following are represented:

[0034] FIG. 1: Sectional view of the hydraulic unit with parallel pumps linked to the servomotor;

[0035] FIG. 2: Enlarged detail of the link of the ball screw to the part linking to the pumps.

DETAILED TECHNICAL DESCRIPTION OF THE INVENTION

[0036] A HYDRAULIC UNIT WITH PARALLEL PUMPS LINKED TO THE SERVOMOTOR relates to a multifunctional hydraulic unit (U), comprised of two hydraulic pumps (1 and 2) mounted in parallel, and can be classified as piston pumps with a major innovative difference, as the pistons represented by the hydraulic rods (3E and 3E′, 4D and 4D′) are static, fixed on roller bearing (4S) and on the base (41), and what moves to perform the pumping are the hydraulic sleeves (5E and 5D) of the hydraulic pumps (1 and 2). The working occurs as follows: the servomotor (6) is coupled on a roller bearing (4S) which has the ball screw (7) coupled on the other face, with the function of displacing the bolt (8) of the ball screw (7) upwardly or downwardly, according to the rotation direction of the servomotor (6). When the ball screw (7) is turning clockwise, for example, the bolt (8) of the ball screw (7) which is coupled and fixed on a connecting part (9) between the two hydraulic pumps (1 and 2), begins to be displaced upwards, taking with it the hydraulic sleeves (5E and 5D) of the two hydraulic pumps (1 and 2) which, as already mentioned, are interlinked to each other through this connecting part (9).

[0037] Therefore, the hydraulic sleeves (5E and 5D) of the hydraulic pumps (1 and 2) slide on the hydraulic rods (3E and 3E′, 4D and 4D′), which are static and fixed on the roller bearing (4S) and on the base (41). When the hydraulic sleeves (5E and 5D) of the hydraulic pumps (1 and 2) begin to rise, the oil that is idle in the lower hydraulic chamber (11E and 11D) begins to be pressured and starts to move outwardly, passing first through the oil passage hole (FE′ and FD′) of the lower hydraulic chamber (11E and 11D), passing through the lower hydraulic rod (3E′ and 4D′) exiting through the hole (21 and 22) opening the lower check valve (V3 and V4) and passing through it to be stored in the hydraulic pressure accumulators (14E and 14D), where it will remain idle and ready to be used, when necessary, by means of the manifold block (15 and 16).

[0038] In the same upward movement, while the hydraulic oil is being displaced into the hydraulic pressure accumulators (14E and 14D), oil from the upper hydraulic chamber (10E and 10D) is being filled simultaneously, by means of a suction generated by the hydraulic plunger (17E and 17D) of the hydraulic pump (1 and 2), which draws the oil from the oil reservoir (18) passing through the suction filter (23 and 24) which force the opening of the upper check valve (VI and V2), passing through the hole (13 and 14), where it is led through the inside of the upper hydraulic rod (3E and 4D), subsequently arriving at the upper hydraulic chamber (10E and 10D), remaining idle.

[0039] Upon arriving at the end of the displacement stroke of the hydraulic sleeve (5E and 5D) of the hydraulic pumps (1 and 2), still in the upward movement, an electronic command is given and inversion occurs in the rotation direction of the servomotor (6), meaning the ball screw (7) begins to turn in the opposite direction, that is, counter-clockwise, displacing the bolt (8) of the ball screw (7) downward and taking with it the two hydraulic pumps (1 and 2), which now being to compress the oil which was idle in the upper hydraulic chamber (10E and 10D), meaning it is led to the oil passage hole (FE and FD) of the upper hydraulic chamber (10E and 10D), passing through the inside of the upper hydraulic rod (3E and 4D) and exiting through the hole (12 and 13), forcing the opening of the upper check valve (VI and V2) and storing inside the hydraulic pressure accumulators (14E and 14D), remaining idle and ready to be used, when necessary, by means of the manifold block (15 and 16).

[0040] During the descent of the hydraulic pumps (1 and 2), the oil begins to fill the lower hydraulic chamber (11E and 11D), by means of the suction performed by the hydraulic plunger (17E and 17D), which draws the oil passing through the suction filter (19 and 20), forcing the opening of the lower check valve (V3 and V4) which pushes the oil from the oil reservoir (18), passing through the hole (21 and 22) of the lower hydraulic chamber (11E and 11D), being led through the lower hydraulic rod (3E′ and 4D′) and arriving at the lower hydraulic chamber (11E and 11D), passing through the oil passage hole (FE′ and FD′), entering into a continuous pumping regime.

[0041] When the hydraulic pressure accumulators (14E and 14D) are full, there will be an increase in hydraulic pressure, which will activate the pressure sensor (25) which will control the halting of the servomotor (6) and, consequently, it will stop pumping, keeping the system on-hold.

[0042] At the time where one of the actuators, of the machine that will use this invention, moves, there will be a minor drop in internal pressure of the hydraulic pressure accumulators (14E and 14D), and the pressure sensor (25) will automatically control the immediate working of the hydraulic pump (1 and 2), which will instantly replace the volume of oil that was used. If the actuators used no oil, then the hydraulic pumps (1 and 2) will remain idle, but keeping the entire system pressurized.

[0043] This invention also enables four different hydraulic pressures to be produced simultaneously, two pressures in the upward movement and two pressures in the downward movement.

[0044] Producing four different pressures, without altering the electronic parameters of the equipment, is possible because the two hydraulic sleeves (5E and 5D), despite having the same internal diameter, may have the diameters of the hydraulic rods (3E and 3E′, 4D and 4D′) that are different to each other, that is to say, different areas in the upper hydraulic chamber (10E and 10D) and in the lower hydraulic chamber (11E and 11D) which, receiving the same force, will result in different pressures and, in this case, each hydraulic chamber (10E, 10D, 11E, 11D) may be linked to its own hydraulic pressure accumulator (14E and 14D), which enables greater flexibility and versatility to this invention.