Clamp lifting and following buffering system and method

Abstract

The present invention discloses a clamp lifting follow-up buffer system and method, the system comprises: an accumulator, the front end of which is connected to a hydraulic circuit through a switch valve, and is used to connect to the hydraulic circuit for passive follow-up buffering when the switch valve is opened; a position sensor, which is arranged on the clamp lifting mechanism, and is used to obtain the position of the clamp lifting mechanism; a control module, which communicates with a press to obtain the pressing amount of each forging, and communicates with the position sensor to obtain the current position of the clamp lifting mechanism, and is connected with the switch valve and a proportional valve, and is used to control the opening of the switch valve to perform passive follow-up buffering when the pressing amount is less than or equal to 50mm, and to control the opening of the proportional valve to perform active follow-up buffering when the pressing amount is greater than 50mm, or to return to follow after the active follow-up buffering is completed. Not only is the structure simple and easy to build, but it can also be flexibly applied, so that the clamp lifting mechanism buffering operation is stable and the positioning is accurate, thereby improving the quality of forgings and the yield rate.

Description

Technical Field

[0001] The invention relates to the technical field of forging processing, and in particular to a clamp lifting and following buffering system and method. Background Art

[0002] In the traditional forging production process, the buffering of the clamp lifting mechanism is often combined with manual control and accumulators. Since this method relies heavily on the operator's experience and the flow of the accumulator cannot be accurately controlled, it will cause abnormal buffering during the forging process, bending of the forging, and even damage to the mechanical structure. Summary of the invention

[0003] In order to solve some or all of the technical problems existing in the above-mentioned prior art, the present invention provides a clamp lifting and following buffering system and method. The technical solution is as follows:

[0004] In the first aspect, a clamp lifting and following buffering system is provided, in which the clamp lifting mechanism is controlled by a hydraulic circuit, and a proportional valve is provided on the hydraulic circuit for controlling the lifting speed through the flow of the proportional valve, and the clamp lifting and following buffering system comprises: an accumulator, a front end of which is connected to the hydraulic circuit through a switch valve, and is connected to the hydraulic circuit for passive following buffering when the switch valve is opened; a position sensor, which is provided on the clamp lifting mechanism and is used to obtain the position of the clamp lifting mechanism; a control module, which communicates with a press to obtain the pressing amount of each forging, and communicates with the position sensor to obtain the current position of the clamp lifting mechanism, and is connected to the switch valve and the proportional valve, and is used to control the opening of the switch valve for passive following buffering when the pressing amount is less than or equal to 50 mm, and to control the opening of the proportional valve for active following buffering when the pressing amount is greater than 50 mm, or to return following after the active following buffering ends.

[0005] In some optional implementations, the position sensor is an encoder.

[0006] In some optional implementations, the accumulator is connected to the hydraulic circuit through two one-way valves with opposite flow directions. When the clamp lifting mechanism descends, the liquid is pressed into the accumulator through one of the one-way valves. When the clamp lifting mechanism rises, the accumulator releases pressure and the liquid is pressed into the hydraulic circuit through the other one-way valve.

[0007] In some optional implementations, the control module is a PLC, which stores background data blocks of elastic modulus corresponding to ingot temperature, yield strength corresponding to ingot temperature, and a characteristic curve of the corresponding relationship between proportional valve opening and flow value.

[0008] In a second aspect, a method for performing clamp lifting and following buffering using the clamp lifting and following buffering system described in any one of the above items is provided, comprising:

[0009] The control module obtains the pressing amount of the forging from the press;

[0010] When the pressing amount is less than or equal to 50mm, the control module controls the switch valve to open so that the accumulator is connected to the hydraulic circuit of the clamp lifting mechanism for passive follow-up buffering;

[0011] When the pressing amount is greater than 50mm, the control module obtains the buffer speed and buffer target value, and controls the opening of the proportional valve according to the buffer speed and buffer target value to perform active follow-up buffering;

[0012] After the active following buffering is completed, the control module uses the working zero point as the return target value and controls the opening of the proportional valve to perform return following buffering.

[0013] In some optional implementations, the control module obtains the buffering speed and the buffering target value in the following manner:

[0014] The control module communicates with the press to obtain the pressing speed as the buffer speed;

[0015] The control module communicates with the press to obtain the pressing amount, billet temperature and billet radius, and determines the buffer target value through the following formula:

[0016]

[0017] In the formula, l is the buffer target value, h is the pressure reduction, σ s is the yield strength, T is the ingot temperature, R is the ingot radius, and E is the elastic modulus.

[0018] In some optional implementations, the control module stores background data blocks of elastic modulus corresponding to the ingot temperature and yield strength corresponding to the ingot temperature, and the control module determines the elastic modulus and yield strength corresponding to the ingot temperature according to the ingot temperature addressing.

[0019] In some optional implementations, the control module controls the opening of the proportional valve according to the buffering speed and the buffering target value to perform active follow-up buffering, including:

[0020] The control module uses the buffer speed as the following speed, converts the following speed value into a percentage to correspond to the flow value of the proportional valve, and then adjusts the proportional valve to the opening corresponding to the flow value according to the proportional valve flow characteristic curve;

[0021] The difference between the working zero point and the current position of the clamp lifting mechanism is compared with the buffer target value, and active following is stopped after reaching the buffer target position. The working zero point is the contact position between the clamp lifting mechanism and the forging, and the current position of the clamp lifting mechanism is obtained by a position sensor.

[0022] In some optional implementations, the control module controls the opening of the proportional valve to perform return follow buffering, including:

[0023] The control module takes 4 / 5 of the press return speed as the following speed, converts the following speed value into a percentage to correspond to the flow value of the proportional valve, and then adjusts the proportional valve to the opening corresponding to the flow value according to the proportional valve flow characteristic curve. The clamp lifting mechanism stops returning and following after reaching the working zero point.

[0024] The main advantages of the technical solution of the present invention are as follows:

[0025] The clamp lifting follow-up buffer system and method of the present invention can be adjusted to a passive follow-up buffer mode or an active follow-up buffer mode according to the pressing amount, and can also perform return follow-up after the active follow-up buffer. It is not only simple in structure and easy to build, but also flexible in application, so that the clamp lifting mechanism has a smooth buffering operation and precise positioning, thereby improving the quality and yield of forgings, reducing the possibility of damage to the mechanical structure, having a good economic effect, and having a good application effect and application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the embodiments of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0027] Figure 1 A schematic diagram of the structure of a hydraulic circuit in which an accumulator is connected to a clamp lifting mechanism according to an embodiment of the present invention;

[0028] Figure 2 A schematic diagram of the electrical control of a clamp lifting and following buffer system provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] The technical solution provided by the embodiments of the present invention is described in detail below with reference to the accompanying drawings.

[0031] In the first aspect, the embodiment of the present invention provides a clamp lifting and following buffering system, which is suitable for buffering of a clamp lifting mechanism controlled by hydraulic pressure. The clamp lifting mechanism is controlled by a hydraulic circuit, and the structure of the hydraulic circuit can be seen in the attached Figure 1 , a proportional valve is provided on the hydraulic circuit, which is used to control the lifting speed through the flow of the proportional valve. The clamp lifting and following buffering system provided in this embodiment includes: an accumulator, whose front end is connected to the hydraulic circuit through a switch valve, and is used to connect to the hydraulic circuit for passive following buffering when the switch valve is opened. The position sensor is arranged on the clamp lifting mechanism, and is used to obtain the position of the clamp lifting mechanism. The control module communicates with the press to obtain the pressing amount of each forging, and communicates with the position sensor to obtain the current position of the clamp lifting mechanism, and is connected to the switch valve and the proportional valve, and is used to control the opening of the switch valve for passive following buffering when the pressing amount is less than 50mm, and to control the opening of the proportional valve for active following buffering when the pressing amount is greater than or equal to 50mm, or to return to follow after the active following buffering ends. The electrical control schematic diagram of the above-mentioned components can be found in the attached figure. Figure 2 .

[0032] The working principle of the clamp lifting and following buffer system provided in the embodiment of the present invention is described below:

[0033] When in use, the control module obtains the pressing amount of the forged forging from the press.

[0034] When the pressing amount is less than or equal to 50mm, the control module controls the switch valve to open so that the accumulator is connected to the hydraulic circuit of the clamp lifting mechanism for passive follow-up buffering. Passive follow-up buffering can be applied to the finishing process of high speed and small pressing amount.

[0035] When the pressing amount is greater than 50mm, the control module obtains the buffer speed and the buffer target value, and controls the opening of the proportional valve according to the buffer speed and the buffer target value to perform active follow-up buffering.

[0036] After the active following buffering is completed, the control module uses the working zero point as the return target value and controls the opening of the proportional valve to perform return following buffering.

[0037] It can be seen that the clamp lifting and following system provided in the embodiment of the present invention can be adjusted to a passive following and buffering mode or an active following and buffering mode according to the amount of pressing down, and can also perform return following after active following and buffering. It is not only simple in structure and easy to build, but also flexible in application, so that the buffering operation of the clamp lifting mechanism is smooth and the positioning is precise, thereby improving the quality and yield of forgings, reducing the possibility of damage to the mechanical structure, having a good economic effect, and having a good application effect and application prospect.

[0038] In this embodiment, the position sensor is used to detect the current position of the clamp lifting mechanism and send it to the control module. For example, the position sensor can be an encoder. Of course, it can also be an infrared sensor, a displacement sensor or other devices that can detect the position, which is not limited in this embodiment.

[0039] In some optional implementations of this embodiment, the accumulator is connected to the hydraulic circuit through two one-way valves with opposite flow directions. When the clamp lifting mechanism descends, the liquid is pressed into the accumulator through one of the one-way valves. When the lifting mechanism rises, the accumulator releases pressure and the liquid is pressed into the hydraulic circuit through the other one-way valve. By connecting the two one-way valves to the hydraulic circuit, the accumulator energy storage and release processes do not interfere with each other and can be switched seamlessly. At this time, the two one-way valves can be directly used as switch valves, and the control module directly controls the opening and closing of the two one-way valves to control whether the accumulator is connected to the hydraulic circuit.

[0040] As attached Figure 1 As shown, the outlet of the accumulator is also connected to a pressure reducing valve and a stop valve. The pressure reducing valve can automatically release pressure when the pressure exceeds the set value to ensure that the pressure does not exceed the set value and ensure safety. The stop valve is the only way for the liquid to flow. When the pressure is pressed down, the liquid passes through one of the one-way valves and then passes through the stop valve to enter the accumulator. When the pressure rises, the liquid in the accumulator flows out through the stop valve and then passes through another one-way valve to enter the hydraulic pipeline. It can be seen that by opening and closing the stop valve, whether the accumulator is enabled can be controlled. That is, in some optional implementations, the stop valve can also be used as a switch valve.

[0041] The accumulator can be a piston accumulator. The number of accumulators can be multiple. Since the energy storage capacity of a single accumulator is limited, a larger load capacity can be achieved by setting multiple groups of accumulators. The specific number can be designed by technicians in this field according to the tonnage and the buffer height during passive follow-up buffering, as long as it can meet the use requirements.

[0042] In some optional implementations of this embodiment, the control module is a PLC, which stores background data blocks of elastic modulus corresponding to the ingot temperature and yield strength corresponding to the ingot temperature, so that the control module can determine the elastic modulus and yield strength according to the ingot temperature, and then determine the buffer target value. In addition, a characteristic curve of the corresponding relationship between the proportional valve opening and the flow value is stored therein, so that the control module can adjust the proportional valve opening so that the proportional valve reaches the set flow value.

[0043] In a second aspect, an embodiment of the present invention provides a method for performing clamp lifting and following buffering using any of the clamp lifting and following buffering systems described above, comprising:

[0044] The control module obtains the pressing amount of the forging from the press.

[0045] When the amount of depression is less than or equal to 50mm, the control module controls the switch valve to open so that the accumulator is connected to the hydraulic circuit of the clamp lifting mechanism for passive follow-up buffering. That is, when the clamp lifting mechanism descends, the liquid is pressed into the accumulator through one of the one-way valves, and the accumulator stores energy. When the lifting mechanism rises, the accumulator releases pressure, and the liquid is pressed into the hydraulic circuit through the other one-way valve, and the accumulator releases energy for passive follow-up buffering.

[0046] When the pressing amount is greater than 50mm, the control module obtains the buffer speed and the buffer target value, and controls the opening of the proportional valve according to the buffer speed and the buffer target value to perform active follow-up buffering.

[0047] After the active following buffering is completed, the control module uses the working zero point as the return target value and controls the opening of the proportional valve to perform return following buffering.

[0048] It can be seen that the clamp lifting and following method provided in the embodiment of the present invention can be adjusted to a passive following and buffering mode or an active following and buffering mode according to the amount of pressing down, and return following can be performed after the active following and buffering. It is not only simple in structure and easy to build, but also flexible in application, so that the clamp lifting mechanism has a smooth buffering operation and precise positioning, thereby improving the quality and yield of forgings, reducing the possibility of damage to the mechanical structure, having a good economic effect, and having a good application effect and application prospect.

[0049] Specifically, the control module obtains the buffering speed and the buffering target value in the following manner:

[0050] The control module communicates with the press to obtain the pressing speed as the buffer speed;

[0051] The control module communicates with the press to obtain the pressing amount, billet temperature and billet radius, and determines the buffer target value through the following formula:

[0052]

[0053] In the formula, l represents the buffer target value, h is the pressure reduction, σ s is the yield strength, T is the ingot temperature, R is the ingot radius, and E is the elastic modulus.

[0054] Among them, the pressing amount, billet radius, billet temperature, etc. are directly obtained by the communication between the control module and the press. The control module stores background data blocks of the elastic modulus corresponding to the billet temperature and the yield strength corresponding to the billet temperature. The control module determines the elastic modulus and yield strength corresponding to the billet temperature according to the billet temperature addressing.

[0055] The control module controls the opening of the proportional valve according to the buffering speed and the buffering target value to perform active follow-up buffering, including:

[0056] The control module uses the buffer speed as the following speed, converts the following speed value into a percentage to correspond to the flow value of the proportional valve, and then adjusts the proportional valve to the opening corresponding to the flow value according to the proportional valve flow characteristic curve. This process is active following buffering;

[0057] During the active following buffering process, the difference between the working zero point and the current position of the clamp lifting mechanism is compared with the buffering target value. The active following is stopped after reaching the buffering target position. The working zero point is the contact position between the clamp lifting mechanism and the forging, which is directly obtained by the communication between the control module and the press. The current position of the clamp lifting mechanism is obtained through the position sensor, which is obtained by direct communication between the control module and the position sensor.

[0058] The control module controls the opening of the proportional valve to perform return follow buffering, including:

[0059] The control module takes 4 / 5 of the press return speed as the following speed, converts the following speed value into a percentage to correspond to the flow value of the proportional valve, and then adjusts the proportional valve to the opening corresponding to the flow value according to the proportional valve flow characteristic curve. The clamp lifting mechanism stops returning and following after reaching the working zero point.

[0060] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, "front", "back", "left", "right", "upper" and "lower" in this article are all referenced to the placement state shown in the accompanying drawings.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A clamp lifting and following buffer system, the clamp lifting mechanism is controlled by a hydraulic circuit, a proportional valve is provided on the hydraulic circuit, and the lifting speed is controlled by the flow of the proportional valve, characterized in that: The clamp lifting and following buffer system comprises: An accumulator, the front end of which is connected to the hydraulic circuit via a switch valve, and is used to be connected to the hydraulic circuit for passive following buffering when the switch valve is opened; A position sensor, disposed on the clamp lifting mechanism, for obtaining the position of the clamp lifting mechanism; The control module communicates with the press to obtain the pressing amount of each forging, and communicates with the position sensor to obtain the current position of the clamp lifting mechanism, and is connected to the switch valve and the proportional valve, and is used to control the opening of the switch valve to perform passive follow-up buffering when the pressing amount is less than or equal to 50 mm, and to control the opening of the proportional valve to perform active follow-up buffering when the pressing amount is greater than 50 mm, or to perform return follow-up after the active follow-up buffering ends.

2. The clamp lifting and following buffer system according to claim 1 is characterized in that: The position sensor is an encoder.

3. The clamp lifting and following buffer system according to claim 1 is characterized in that: The accumulator is connected to the hydraulic circuit through two one-way valves with opposite flow directions. When the clamp lifting mechanism descends, the liquid is pressed into the accumulator through one of the one-way valves. When the clamp lifting mechanism rises, the accumulator releases pressure and the liquid is pressed into the hydraulic circuit through the other one-way valve.

4. The clamp lifting and following buffer system according to claim 1 is characterized in that: The control module is a PLC, which stores background data blocks of elastic modulus corresponding to ingot temperature, yield strength corresponding to ingot temperature, and a characteristic curve of the corresponding relationship between proportional valve opening and flow value.

5. A method for performing clamp lifting and following buffering using the clamp lifting and following buffering system according to any one of claims 1 to 4, characterized in that: include: The control module obtains the pressing amount of the forging from the press; When the pressing amount is less than or equal to 50mm, the control module controls the switch valve to open so that the accumulator is connected to the hydraulic circuit of the clamp lifting mechanism for passive follow-up buffering; When the pressing amount is greater than 50mm, the control module obtains the buffer speed and buffer target value, and controls the opening of the proportional valve according to the buffer speed and buffer target value to perform active follow-up buffering; After the active following buffering is completed, the control module uses the working zero point as the return target value and controls the opening of the proportional valve to perform return following buffering.

6. The clamp lifting and following buffering method according to claim 5, characterized in that: The control module obtains the buffering speed and buffering target value in the following way: The control module communicates with the press to obtain the pressing speed as the buffer speed; The control module communicates with the press to obtain the pressing amount, billet temperature and billet radius, and determines the buffer target value through the following formula: In the formula, l is the buffer target value, h is the pressure reduction, σ s is the yield strength, T is the ingot temperature, R is the ingot radius, and E is the elastic modulus.

7. The clamp lifting and following buffering method according to claim 6, characterized in that: The control module stores background data blocks of elastic modulus corresponding to the ingot temperature and yield strength corresponding to the ingot temperature. The control module determines the elastic modulus and yield strength corresponding to the ingot temperature according to the ingot temperature addressing.

8. The clamp lifting and following buffering method according to claim 7, characterized in that: The control module controls the opening of the proportional valve according to the buffering speed and the buffering target value to perform active follow-up buffering, including: The control module uses the buffer speed as the following speed, converts the following speed value into a percentage to correspond to the flow value of the proportional valve, and then adjusts the proportional valve to the opening corresponding to the flow value according to the proportional valve flow characteristic curve; The difference between the working zero point and the current position of the clamp lifting mechanism is compared with the buffer target value, and active following is stopped after reaching the buffer target position. The working zero point is the contact position between the clamp lifting mechanism and the forging, and the current position of the clamp lifting mechanism is obtained by a position sensor.

9. The clamp lifting and following buffering method according to claim 8, characterized in that: The control module controls the opening of the proportional valve to perform return follow buffering, including: The control module takes 4 / 5 of the press return speed as the following speed, converts the following speed value into a percentage to correspond to the flow value of the proportional valve, and then adjusts the proportional valve to the opening corresponding to the flow value according to the proportional valve flow characteristic curve. The clamp lifting mechanism stops returning and following after reaching the working zero point.

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