CN217633234U - Frame top cover opening and closing hydraulic device - Google Patents

Abstract

The utility model relates to a frame top cap hydraulic means that opens and shuts belongs to the hydraulic control field. The hydraulic cylinder is connected with an explosion-proof valve, a high-pressure ball valve, an overflow valve, an external control one-way valve, a one-way valve group, a throttle valve, a pressure reducing valve, a two-position four-way reversing valve and a proportional reversing valve which are arranged in a rod cavity and a rodless cavity of the hydraulic cylinder. When the hydraulic cylinder extends and retracts, the influence of load change caused by position change of the top cover of the machine frame in the opening and closing process can be avoided, and the speed of the opening and closing process of the top cover of the machine frame can be stably controlled. After the top cover of the frame is opened or closed in place, the pressure of the two cavities of the hydraulic cylinder can be completely released, and no additional pressure is added to a supporting seat of the frame or base equipment. The explosion-proof valve is directly installed on the hydraulic cylinder, so that damage caused by sudden drop of heavy objects due to leakage of hoses and the like can be prevented. The proportional valve can perform speed slope control at the stage of starting and closing the top cover of the frame to realize 'light taking and light putting' and reduce the inertia impact damage of the heavy object.

Description

Frame top cover opening and closing hydraulic device

Technical Field

The utility model belongs to the hydraulic control field relates to a frame top cap hydraulic means that opens and shuts.

Background

In the field of steel pipe rolling, a stand of a single-stand large-caliber rolling mill is composed of a lower fixed base and an upper movable top cover, and the upper top cover is opened or closed by two hydraulic cylinders. When the roller is replaced, the rotating top cover on the rack is opened through the two hydraulic cylinders, the movement is mechanical synchronization, and the rotating top cover falls on a fixed supporting seat after being opened, so that the three rollers can be safely hoisted, replaced and the like. After the rolling is finished, the hydraulic cylinder retracts, the top cover is closed, and after the auxiliary mechanism locks the top cover, the steel pipe can be rolled.

The weight of the opening and closing movement part of the top cover of the rack is more than 100 tons, the stress of the hydraulic cylinder changes along with the change of the rotation angle of the top cover in the opening and closing process of the top cover, and the positive and negative alternating changes of the stress of the hydraulic cylinder exist. During the opening of the top cover, the hydraulic cylinder extends, and the maximum load of the hydraulic cylinder occurs at the starting point of extension, which is about 440t. During the movement, the load becomes gradually smaller and changes from positive to negative, and the maximum negative load is about 200t and appears at the fully opened position of the machine frame. Conversely, during the closing of the head, the hydraulic cylinder retracts and the maximum load of the hydraulic cylinder occurs at the start of retraction, which is about 200t. During the movement, the load is gradually reduced and changed from positive load to negative load, and the maximum negative load is 440t.

The top cover of the machine frame has the following problems to be solved in the opening and closing process:

1. according to the action process of the equipment, the situation of negative load exists in the two movement directions of opening and closing of the top cover, if a pressure-bearing side pipeline or a valve is burst or leaked, the equipment cannot be controlled to fall in an accelerated way, 100 tons of equipment generates very large inertia force, the equipment can be greatly damaged, and even the safety of personnel is threatened.

2. Since the hydraulic cylinder has load change in size and direction during extending and retracting, the conventional fixed throttle control inevitably causes instability of movement speed along with the change of pressure difference on two sides of the throttle. Especially after the extended or retracted position changes from a positive load to a negative load, the negative load gradually increases and the device will accelerate to fall.

3. From the mechanism, the top cover rotates around a fixed point in the opening and closing process, the linear speed of the top cover at the farthest end of the top cover around the fixed point has a magnification relation relative to the hydraulic cylinder, and the magnification system is between 4 and 6 times. Meaning the top cap is when closing completely, even the pneumatic cylinder speed is lower, the contact velocity of top cap and unable adjustment base is also faster, and the top cap contacts with the base in the twinkling of an eye, can produce great striking.

4. After the top cover is closed, an auxiliary mechanism is used for pressurizing and locking the top cover, in the locking process, the frame opening and closing hydraulic cylinder is required to have no additional force to act on the top cover, and two cavities of the frame opening and closing hydraulic cylinder cannot be subjected to pressure building or air suction.

SUMMERY OF THE UTILITY MODEL

In view of the above, an object of the present invention is to provide a hydraulic device for opening and closing a top cover of a rack, so as to solve the above problems.

In order to achieve the above purpose, the utility model provides a following technical scheme:

a hydraulic device for opening and closing a top cover of a frame comprises a first hydraulic cylinder, wherein a rodless cavity of the first hydraulic cylinder is connected to an A port of a proportional reversing valve through a first high-pressure ball valve, a first external control one-way valve and a first one-way valve group; a rod cavity of the first hydraulic cylinder is connected to a port B of a proportional reversing valve through a second high-pressure ball valve, a second external control one-way valve and a second one-way valve group, a port P of the proportional reversing valve is connected to a high-pressure oil way, and a port T of the proportional reversing valve is connected to an oil return way; the first check valve group comprises four check valves, two of the four check valves form a group, and the check valves in each group have the same flow direction; a first throttle valve and a first pressure reducing valve are connected between the two groups of one-way valves; the second check valve group comprises four check valves, two of the four check valves are in one group, and the check valves in each group have the same flow direction; and a second throttle valve and a second pressure reducing valve are connected between the two groups of check valves.

Optionally, the hydraulic system further comprises a second hydraulic cylinder connected in parallel with the first hydraulic cylinder.

Optionally, the rodless cavity of the first hydraulic cylinder is connected to the first high-pressure ball valve through a first explosion-proof valve; and the rodless cavity of the second hydraulic cylinder is connected to the first high-pressure ball valve through a third explosion-proof valve.

Optionally, the rod cavity of the first hydraulic cylinder is connected to the second high-pressure ball valve through a second explosion-proof valve; and a rod cavity of the second hydraulic cylinder is connected to the second high-pressure ball valve through a fourth explosion-proof valve.

Optionally, the rodless cavity of the first hydraulic cylinder is connected to the oil return path through a first overflow valve, and the rod cavity of the first hydraulic cylinder is connected to the oil return path through a second overflow valve.

Optionally, the system further comprises a two-position four-way reversing valve for controlling the on-off of the first external control one-way valve and the second external control one-way valve.

The beneficial effects of the utility model reside in that:

1. once the top cover of the rack stalls and is out of control in the opening and closing processes, the top cover of the rack can be automatically locked without other detection elements and electrical control.

2. In the opening and closing process of the top cover of the rack, the speed is stable and does not change along with the change of the load.

And 3, before the top cover of the rack is closed, the speed is reduced in advance, and the collision between the top cover of the rack and the base is avoided.

4. Before the auxiliary locking mechanism of the top cover of the frame is locked, the pressure of two cavities of the hydraulic cylinder is released in advance, so that the blocking cavity of the hydraulic cylinder is prevented from being suppressed or the rod cavity is prevented from being emptied.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and/or combinations particularly pointed out in the appended claims.

Drawings

For the purposes of promoting a better understanding of the objects, features and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:

fig. 1 is a hydraulic schematic diagram of the present invention.

Fig. 2 is a schematic view of a rack top cover closing mechanism.

Fig. 3 is a schematic diagram of a rack top cover opening mechanism.

Reference numerals: the hydraulic control system comprises a first hydraulic cylinder 1.1, a second hydraulic cylinder 1.2, a first explosion-proof valve 2.1, a second explosion-proof valve 2.2, a third explosion-proof valve 2.3, a fourth explosion-proof valve 2.4, a first high-pressure ball valve 3.1, a second high-pressure ball valve 3.2, a first overflow valve 4.1, a second overflow valve 4.2, a first external control one-way valve 5.1, a second external control one-way valve 5.2, a first one-way valve group 6.1, a second one-way valve group 6.2, a first throttle valve 7.1, a second throttle valve 7.2, a first pressure reducing valve 8.1, a second pressure reducing valve 8.2, a two-position four-way reversing valve 9 and a proportional reversing valve 10.

Detailed Description

The following embodiments of the present invention are provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can be implemented or applied by other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the features in the following embodiments and examples may be combined with each other without conflict.

Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in any way limiting the scope of the invention; for a better explanation of the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "back", etc., indicating directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for convenience of description and simplification of description, but it is not intended to indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore, the terms describing the positional relationships in the drawings are only used for illustrative purposes and are not to be construed as limiting the present invention, and those skilled in the art can understand the specific meanings of the terms according to specific situations.

Referring to fig. 1 to 3, a hydraulic device for opening and closing a top cover of a frame includes a first hydraulic cylinder 1.1, a second hydraulic cylinder 1.2, a first explosion-proof valve 2.1, a second explosion-proof valve 2.2, a third explosion-proof valve 2.3, a fourth explosion-proof valve 2.4, a first high-pressure ball valve 3.1, a second high-pressure ball valve 3.2, a first overflow valve 4.1, a second overflow valve 4.2, a first external control check valve 5.1, a second external control check valve 5.2, a first check valve group 6.1, a second check valve group 6.2, a first throttle valve 7.1, a second throttle valve 7.2, a first pressure reducing valve 8.1, a second pressure reducing valve 8.2, a two-position four-way directional valve 9, and a proportional directional valve 10.

At the stage of opening the top cover of the machine frame

The cylinder rods of the first 1.1 and second 1.2 cylinders extend outwardly from the fully retracted state. The single-electromagnet two-position four-way reversing valve 9 electromagnet YVH1.A is electrified, the first external control one-way valve 5.1 and the second external control one-way valve 5.2 are opened, the proportional reversing valve 10 gives positive opening degree and is in a parallel position, hydraulic oil enters a plug cavity of the hydraulic cylinder through the first one-way valve group 6.1, the first reducing valve 8.1, the first throttling valve 7.1, the first external control one-way valve 5.1, the first high-pressure ball valve, the first explosion-proof valve 2.1 and the fourth explosion-proof valve 2.4. The hydraulic oil in pole chamber passes through second explosion-proof valve 2.2 and third explosion-proof valve 2.3, second high pressure ball valve 3.2, second external control check valve 5.2, second check valve group 6.2, second relief pressure valve 8.2, second choke valve 7.2, and proportional reversing valve 10, gets back to the T pipe. In the first half of the opening of the top cover of the frame, the load is positive and gradually decreases. At this time, the cylinder speed is controlled by the first pressure reducing valve 8.1 and the first throttle valve 7.1. Once the opening of the first throttle 7.1 is set, its flow capacity is determined by the pressure difference across it, which is ensured by the first pressure reducing valve 8.1. As the load becomes smaller, the outlet side pressure of the first throttle 7.1 decreases, the spring side oil pressure of the first reducing valve 8.1 decreases, and the main spool of the first reducing valve 8.1 reduces the opening degree of the first reducing valve 8.1 under the action of the non-spring side oil pressure, so that the pressure after the first reducing valve 8.1 (before the first throttle 7.1) decreases until the pressure decreases to be equal to the outlet pressure of the first throttle 7.1 + the spring force of the first reducing valve 8.1. Therefore, the pressure difference between the two cavities of the throttle valve does not change along with the change of the load, and the fixed value is always kept, so that the flow stability, namely the extension speed of the hydraulic cylinder is stable.

At the back half section that the frame top cap was opened, the load becomes the negative value by the positive value, and the load plays the power effect, drives the pneumatic cylinder and stretches out. The force is the component of the gravity of the frame and is gradually increased along with the opening degree of the frame. If the oil return cavity of the hydraulic cylinder has no speed reduction measure, the equipment can fall under the action of the gravity component of the rack in an accelerated manner. At this point the cylinder speed is controlled by the second pressure reducing valve 8.2 and the second throttle 7.2. Once the opening degree of the second throttle 7.2 is set, the flow capacity is determined by the pressure difference between the front and the rear, the pressure difference between the front and the rear is ensured by the second pressure reducing valve 8.2, and the pressure difference between the front and the rear of the second throttle 7.2 is always equal to the set pressure of the pressure reducing valve spring under the action of the second pressure reducing valve 8.2. As the load force increases, the hydraulic cylinder rod chamber oil pressure increases, and the oil passes through the second check valve group 6.2, the second reducing valve 8.2 and the second throttle valve 7.2. At this time, the pressure at the inlet side of the second reducing valve 8.2 is increased, the pilot oil port of the spring cavity is connected with the oil outlet B of the second throttling valve 7.2 and is at zero pressure, and the pilot oil port at the non-spring side is connected with the oil inlet a of the second throttling valve 7.2. When the pressure of the oil inlet A of the second throttle valve 7.2 is higher than the set pressure of the spring of the second reducing valve 8.2, the second reducing valve 8.2 moves towards the closing direction of the valve core under the action of the force, the opening degree of the valve core is reduced, the pressure difference of the oil inlet and the oil outlet of the second reducing valve 8.2 is increased, the pressure of the outlet of the second reducing valve 8.2 is reduced until the pressure is equal to the set spring force, and the pressures of the two ends of the main valve core are balanced. In this way the pressure difference across the second throttle 7.2 is also equal to the spring set force and the flow capacity remains constant, thus ensuring that the speed of the hydraulic cylinder is constant and does not vary with the load force.

In the closing stage of the top cover of the machine frame

The cylinder rods of the first hydraulic cylinder 1.1 and the second hydraulic cylinder 1.2 are retracted inwards from the fully extended state. The single-electromagnet two-position four-way reversing valve 9 is electrified, the electromagnet YVH1.A is electrified, the first externally-controlled one-way valve 5.1 and the second externally-controlled one-way valve 5.2 are opened, the proportional reversing valve 10 is opened to a negative opening degree and is positioned at a cross position, hydraulic oil passes through the second one-way valve group 6.2, the second pressure reducing valve 8.2, the second throttling valve 7.2, the second externally-controlled one-way valve 5.2, the second high-pressure ball valve 3.2, the second explosion-proof valve 2.2 and the third explosion-proof valve 2.3 and enters a plug cavity of the hydraulic cylinder. The hydraulic oil in the rod cavity passes through a first explosion-proof valve 2.1 and a fourth explosion-proof valve 2.4, a first high-pressure ball valve, a first external control check valve 5.1, a first check valve group 6.1, a first pressure reducing valve 8.1, a first throttling valve 7.1, a proportional reversing valve 10 and returns to the T pipe. In the first half of the closed top cover of the frame, the load is positive and gradually decreases. At this point the cylinder speed is controlled by the second pressure reducing valve 8.2 and the second throttle 7.2. Once the opening of the second throttle 7.2 is set, its flow capacity is determined by the pressure difference across it, which is ensured by the second pressure reducing valve 8.2. As the load becomes smaller, the outlet-side pressure of the second throttle 7.2 decreases, the spring-side oil pressure of the second reducing valve 8.2 decreases, and the main spool of the second reducing valve 8.2 decreases the opening degree of the second reducing valve 8.2 by the non-spring-side oil pressure, so that the pressure after the second reducing valve 8.2 (before the second throttle 7.2) decreases until it is equal to the outlet pressure of the second throttle 7.2 + the spring force of the reducing valve 8.2. Therefore, the pressure difference between the two cavities of the throttle valve does not change along with the change of the load, and the fixed value is always kept, so that the stability of the flow, namely the stability of the extension speed of the hydraulic cylinder is ensured.

At the latter half section that the frame top cap was closed, the load becomes the negative value by the positive value, and the load plays power effect, drives the pneumatic cylinder and withdraws. The force is the component of the gravity of the machine frame and is gradually increased along with the closing degree of the machine frame. If the oil return cavity of the hydraulic cylinder has no speed reduction measure, the equipment can fall under the action of the gravity component of the rack in an accelerated manner. At this time, the cylinder speed is controlled by the first pressure reducing valve 8.1 and the first throttle valve 7.1. Once the opening degree of the first throttle valve 7.1 is set, the flow capacity is determined by the pressure difference before and after the first throttle valve, the pressure difference before and after the first throttle valve is ensured by the first pressure reducing valve 8.1, and the pressure difference before and after the first throttle valve 7.1 is always equal to the set pressure of the pressure reducing valve spring under the action of the first pressure reducing valve 8.1. As the load force increases, the oil pressure in the rod cavity of the hydraulic cylinder increases, and the oil passes through the first check valve group 6.1, the first reducing valve 8.1 and the throttle valve 7.1. At this time, the pressure at the inlet side of the first reducing valve 8.1 is increased, the pilot port of the spring cavity is connected with the oil outlet B of the first throttling valve 7.1 and is at zero pressure, and the pilot port at the non-spring side is connected with the oil inlet a of the first throttling valve 7.1. When the pressure of the oil inlet A of the first throttle valve 7.1 is higher than the set pressure of the spring of the first reducing valve 8.1, the first reducing valve 8.1 moves towards the closing direction of the valve core under the action of the force, the opening degree of the valve core is reduced, the pressure difference of the oil inlet and the oil outlet of the first reducing valve 8.1 is increased, the pressure of the outlet of the first reducing valve 8.1 is reduced until the pressure is equal to the set spring force, and the pressures of the two ends of the main valve core are balanced. In this way the pressure difference across the first throttle 7.1 is also equal to the spring set force and the flow capacity remains constant, thus ensuring that the speed of the hydraulic cylinder is constant and does not vary with the load force.

The first check valve group 6.1 and the second check valve group 6.2 have the function of ensuring that hydraulic oil firstly passes through the first reducing valve 8.1 or the second reducing valve 8.2 and then enters the first throttle valve 7.1 or the second throttle valve 7.2 no matter hydraulic oil flows in or out from the two valve groups.

A proximity switch is arranged at a small section of position before the top cover of the rack is in contact with the base of the rack in the closing direction, and from the position, a control signal of the proportional reversing valve 10 is set to be a gradually reduced slope signal, so that the closing speed of the rack is reduced, and the stop impact between the top cover of the rack and the base can be reduced to the maximum extent.

After the top cover of the frame is completely closed, the proportional reversing valve 10 is switched to the neutral position first, so that the two cavities of the hydraulic cylinder are communicated with the T pipe. The frame auxiliary locking mechanism locks the frame top cover. And then, the electromagnet YVH1.A of the single-electromagnet two-position four-way reversing valve 9 is powered off, and the top cover of the rack is safely closed.

When the top cover of the rack is opened or closed, if equipment interference or fault occurs, the electromagnet YVH1.A of the controllable reversing valve 9 loses power, the first external control one-way valve 5.1 and the second external control one-way valve 5.2 are closed, and the top cover of the rack can stop at the current position until the fault is processed.

Finally, the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the scope of the claims of the present invention.

Claims (6)

1. The utility model provides a frame top cap open and close hydraulic means which characterized in that: the hydraulic control system comprises a first hydraulic cylinder, wherein a rodless cavity of the first hydraulic cylinder is connected to an A port of a proportional reversing valve through a first high-pressure ball valve, a first external control one-way valve and a first one-way valve group; a rod cavity of the first hydraulic cylinder is connected to a port B of the proportional reversing valve through a second high-pressure ball valve, a second external control one-way valve and a second one-way valve group, a port P of the proportional reversing valve is connected to a high-pressure oil way, and a port T of the proportional reversing valve is connected to an oil return way; the first check valve group comprises four check valves, two of the four check valves form a group, and the check valves in each group have the same flow direction; a first throttle valve and a first pressure reducing valve are connected between the two groups of one-way valves; the second check valve group comprises four check valves, two of the four check valves form a group, and the check valves in each group have the same flow direction; a second throttle valve and a second reducing valve are connected between the two groups of one-way valves.

2. The hydraulic apparatus for opening and closing a top cover of a machine frame according to claim 1, wherein: and the hydraulic system also comprises a second hydraulic cylinder connected with the first hydraulic cylinder in parallel.

3. The frame top cover opening and closing hydraulic device according to claim 2, characterized in that: the rodless cavity of the first hydraulic cylinder is connected to the first high-pressure ball valve through a first explosion-proof valve; and the rodless cavity of the second hydraulic cylinder is connected to the first high-pressure ball valve through a third explosion-proof valve.

4. The hydraulic apparatus for opening and closing a top cover of a machine frame according to claim 2, wherein: the rod cavity of the first hydraulic cylinder is connected to a second high-pressure ball valve through a second explosion-proof valve; and a rod cavity of the second hydraulic cylinder is connected to the second high-pressure ball valve through a fourth explosion-proof valve.

5. The hydraulic apparatus for opening and closing a top cover of a machine frame according to claim 1, wherein: the rodless cavity of the first hydraulic cylinder is connected to the oil return path through a first overflow valve, and the rod cavity of the first hydraulic cylinder is connected to the oil return path through a second overflow valve.

6. The hydraulic apparatus for opening and closing a top cover of a machine frame according to claim 1, wherein: the two-position four-way reversing valve is used for controlling the first external control one-way valve and the second external control one-way valve to be switched on and off.

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