Hydraulic system for controlling accelerated motion of oil cylinder

Abstract

The utility model discloses a hydraulic system for controlling accelerated motion of an oil cylinder, which comprises an oil tank, a hydraulic pump, a first reversing valve, a second reversing valve, the oil cylinder and a hydraulic control one-way valve. A second hydraulic oil pipe is arranged between a port A of the first reversing valve and an inlet of the hydraulic control one-way valve, a third hydraulic oil pipe is arranged between a port B of the first reversing valve and a control port of the hydraulic control one-way valve, and a fourth hydraulic oil pipe is arranged between a port P of the second reversing valve and a rodless cavity of the oil cylinder. A fifth hydraulic oil pipe is arranged between an outlet of the hydraulic control one-way valve and a rodless cavity of the oil cylinder, a sixth hydraulic oil pipe is arranged between a rod cavity of the oil cylinder and a port B of the second reversing valve, and a seventh hydraulic oil pipe is arranged between a port T of the second reversing valve and a port B of the first reversing valve. Accelerated movement of the oil cylinder can be conducted, the structure is compact, and cost is low.

Description

Technical Field

[0001] This utility model relates to the field of blow molding machines, and in particular to a hydraulic system for controlling the accelerated movement of a hydraulic cylinder. Background Technology

[0002] Blow molding machines require a drive mechanism for opening and closing the mold, such as a hydraulic cylinder, to drive the mold opening and closing. For large plastic buckets, the mold volume is large, the stroke of the mold opening and closing is also large, and the mold opening and closing process takes a long time.

[0003] To shorten the time required for mold opening and closing, the movement speed of the hydraulic cylinder needs to be increased. The movement speed of the hydraulic cylinder depends on the size of the cylinder, the size of the hydraulic pump, and the speed of the motor. In practical applications, the hydraulic cylinder has a limited thrust, so its size often cannot be changed. Increasing the size of the hydraulic pump often requires increasing the size of the pump motor, which not only affects the space layout but also greatly increases the cost, necessitating improvements. Utility Model Content

[0004] The main technical problem solved by this utility model is to provide a hydraulic system for controlling the accelerated movement of a hydraulic cylinder, thereby reducing the cost of operation and maintenance.

[0005] To solve the above-mentioned technical problems, the present invention provides a hydraulic system for controlling the accelerated movement of a hydraulic cylinder, comprising: an oil tank, a hydraulic pump, a first directional valve, a second directional valve, a hydraulic cylinder, and a pilot-operated check valve. A first hydraulic pipe is provided between the outlet of the hydraulic pump and the P port of the first directional valve; a second hydraulic pipe is provided between the A port of the first directional valve and the inlet of the pilot-operated check valve; a third hydraulic pipe is provided between the B port of the first directional valve and the control port of the pilot-operated check valve; a fourth hydraulic pipe is provided between the P port of the second directional valve and the rodless chamber of the hydraulic cylinder; a fifth hydraulic pipe is provided between the outlet of the pilot-operated check valve and the rodless chamber of the hydraulic cylinder; a sixth hydraulic pipe is provided between the rod chamber of the hydraulic cylinder and the B port of the second directional valve; a seventh hydraulic pipe is provided between the T port of the second directional valve and the B port of the first directional valve; an eighth hydraulic pipe is provided between the T port of the first directional valve and the oil tank; and a ninth hydraulic pipe is provided between the inlet of the hydraulic pump and the oil tank.

[0006] In a preferred embodiment of the present invention, the first directional valve is a three-position four-way Y-type directional valve.

[0007] In a preferred embodiment of the present invention, the second directional valve is a two-position directional valve.

[0008] In a preferred embodiment of the present invention, a controller is further included, which is connected to the first reversing valve and the second reversing valve to perform switching control.

[0009] In a preferred embodiment of the present invention, a motor for driving the hydraulic pump is also included, and the controller is connected to the motor for operation control.

[0010] In a preferred embodiment of this utility model, a first filter is connected in series on the ninth hydraulic oil pipe.

[0011] In a preferred embodiment of this utility model, a second filter is connected in series on the eighth hydraulic oil pipe.

[0012] In a preferred embodiment of this utility model, an oil cooler is connected in series on the eighth hydraulic oil pipe.

[0013] The beneficial effects of this utility model are as follows: The hydraulic system for controlling the accelerated movement of the oil cylinder pointed out by this utility model has added a second directional valve and a hydraulically controlled check valve, which makes full use of the hydraulic oil discharged from the rod chamber of the oil cylinder to accelerate the movement of the oil cylinder. There is no need to change the original hydraulic pump and oil cylinder, which makes assembly convenient and reduces costs. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0015] Figure 1 This is a schematic diagram of a preferred embodiment of a hydraulic system for controlling the acceleration of a hydraulic cylinder, showing the cylinder extending at normal speed.

[0016] Figure 2 This is a schematic diagram of a preferred embodiment of a hydraulic system for controlling the accelerated movement of a hydraulic cylinder, showing the cylinder extending rapidly.

[0017] Figure 3 This is a schematic diagram of a preferred embodiment of a hydraulic system for controlling the acceleration of a hydraulic cylinder during the retraction and retraction of the cylinder, according to the present invention. Detailed Implementation

[0018] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0019] Please see Figures 1-3The embodiments of this utility model include:

[0020] like Figure 1 The hydraulic system shown for controlling the acceleration of the cylinder includes: an oil tank 6, a hydraulic pump 5, a first directional valve 1, a second directional valve 2, a cylinder 4, a hydraulically controlled check valve 3, and a controller. A first hydraulic oil pipe 11 is provided between the outlet of the hydraulic pump 5 and the P port of the first directional valve 1. In this embodiment, a ninth hydraulic oil pipe 19 is provided between the inlet of the hydraulic pump 5 and the oil tank 6. Hydraulic oil in the ninth hydraulic oil pipe 19 is drawn and sent to the P port of the first directional valve 1.

[0021] The hydraulic pump 5 is driven by the motor 8, and its operation is controlled by a controller connected to the motor 8. A first filter 9 is connected in series on the ninth hydraulic oil pipe 19 to filter the hydraulic oil before it enters the hydraulic pump 5.

[0022] A second hydraulic oil pipe 12 is provided between the A port of the first directional valve 1 and the inlet of the hydraulic control check valve 3. A fifth hydraulic oil pipe 15 is provided between the outlet of the hydraulic control check valve 3 and the rodless chamber of the cylinder 4. When the cylinder 4 extends at normal speed, the hydraulic oil enters the rodless chamber of the cylinder 4 after passing through the hydraulic control check valve 3 and the fifth hydraulic oil pipe 15, pushing the piston rod forward.

[0023] A third hydraulic pipe 13 is provided between port B of the first directional valve 1 and the control port of the hydraulic check valve 3, and a sixth hydraulic pipe 16 is provided between the rod chamber of the cylinder 4 and port B of the second directional valve. Figure 3 As shown, when the cylinder 4 retracts, hydraulic oil is supplied to the rod chamber of the cylinder 4 through port B of the first directional valve 1. Due to the action of the hydraulic control check valve 3, the pressure in the rod chamber of the cylinder 4 increases continuously, and the pressure is transmitted to the control port of the hydraulic control check valve 3 through the third hydraulic oil pipe 13. Finally, the control port of the hydraulic control check valve 3 is opened, realizing the retraction of the cylinder 4.

[0024] A fourth hydraulic oil pipe 14 is provided between the P port of the second directional valve and the rodless chamber of the oil cylinder 4, such as... Figure 2 As shown, at this time, the hydraulic oil in the rod chamber of cylinder 4 returns to the rodless chamber of cylinder 4 through the P port of the second directional valve, increasing the amount of oil entering the rodless chamber of cylinder 4, thereby realizing the accelerated extension movement of cylinder 4, which is beneficial to improving the mold closing speed.

[0025] A seventh hydraulic oil pipe 17 is provided between the T port of the second directional valve 2 and the B port of the first directional valve, and an eighth hydraulic oil pipe 18 is provided between the T port of the first directional valve 1 and the oil tank 6, forming a return oil passage. In this embodiment, a second filter 10 is connected in series on the eighth hydraulic oil pipe 18 to filter the return oil. An oil cooler 7 is connected in series on the eighth hydraulic oil pipe 18 to cool the return oil and prevent the oil temperature from becoming too high.

[0026] In this embodiment, the first directional valve 1 is a three-position four-way Y-type directional valve, and the second directional valve 2 is a two-position directional valve. The controller is connected to the first directional valve 1 and the second directional valve 2 to perform switching control. When

[0027] When hydraulic cylinder 4 does not require rapid action, such as Figure 1 As shown, oil pump 5 draws in oil, YT1 is energized, and hydraulic oil enters the rodless chamber of oil cylinder 4 through the first directional valve 1 and the hydraulic control check valve 3. The oil cylinder pushes the piston rod forward. At the same time, the oil in the rod chamber enters the oil tank 6 after passing through the second directional valve 2 and the first directional valve 1.

[0028] When hydraulic cylinder 4 needs to move rapidly, such as Figure 2 As shown, when the second directional valve 2 is activated, the oil in the rod chamber of the cylinder returns to the rodless chamber of the cylinder after passing through the second directional valve 2, increasing the flow rate and accelerating the cylinder's movement.

[0029] In summary, the hydraulic system for controlling the accelerated movement of a hydraulic cylinder as described in this utility model can accelerate the movement of the hydraulic cylinder, has a compact structure, does not require increasing the size of the hydraulic cylinder and pump, reduces the space occupied, and has low operation and maintenance costs.

[0030] The above are merely embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A hydraulic system for controlling the accelerated movement of a cylinder, characterized in that, include: The system comprises an oil tank, a hydraulic pump, a first directional valve, a second directional valve, a hydraulic cylinder, and a pilot-operated check valve. A first hydraulic pipe is connected between the outlet of the hydraulic pump and the P port of the first directional valve; a second hydraulic pipe is connected between the A port of the first directional valve and the inlet of the pilot-operated check valve; a third hydraulic pipe is connected between the B port of the first directional valve and the control port of the pilot-operated check valve; a fourth hydraulic pipe is connected between the P port of the second directional valve and the rodless chamber of the hydraulic cylinder; a fifth hydraulic pipe is connected between the outlet of the pilot-operated check valve and the rodless chamber of the hydraulic cylinder; a sixth hydraulic pipe is connected between the rod chamber of the hydraulic cylinder and the B port of the second directional valve; a seventh hydraulic pipe is connected between the T port of the second directional valve and the B port of the first directional valve; an eighth hydraulic pipe is connected between the T port of the first directional valve and the oil tank; and a ninth hydraulic pipe is connected between the inlet of the hydraulic pump and the oil tank.

2. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 1, characterized in that, The first directional valve is a three-position four-way Y-type directional valve.

3. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 1, characterized in that, The second directional valve is a two-position directional valve.

4. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 1, characterized in that, It also includes a controller, which is connected to the first reversing valve and the second reversing valve to perform switching control.

5. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 4, characterized in that, It also includes a motor that drives the hydraulic pump, and the controller is connected to the motor to control its operation.

6. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 1, characterized in that, The first filter is connected in series on the ninth hydraulic oil pipe.

7. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 1, characterized in that, A second filter is connected in series on the eighth hydraulic oil pipe.

8. The hydraulic system for controlling the acceleration of the oil cylinder according to claim 1, characterized in that, An oil cooler is connected in series on the eighth hydraulic oil pipe.

Images