Large-tonnage press machine servo master-slave synchronization system and control method

Abstract

The invention belongs to the technical field of forging and stamping, and particularly relates to a large-tonnage press machine servo master-slave synchronization system and a control method.The large-tonnage press machine servo master-slave synchronization system comprises a master transmission system, a slave transmission system and a control system, and each of the master transmission system and the slave transmission system comprises a power assembly and a transmission gear set; the power assembly is used for driving a press sliding block to do vertical reciprocating motion through the transmission gear set, the control system comprises a control unit and a man-machine interaction platform, the control unit receives signals of the man-machine interaction platform, and the master transmission system and the slave transmission system are driven through a master servo driver and a slave servo driver respectively. And the control unit can compensate the operation error of the master and slave transmission systems in real time, so that the consistency of the operation of the master and slave transmission systems is realized. The characteristics of the servo motor and a driving control system of the servo motor can be fully utilized, control over the large-tonnage press sliding block becomes more flexible, the control precision and action sensitivity of the large-tonnage press sliding block are improved, action cooperation of the large-tonnage press sliding block and an automatic feeding system is better, and then the production takt and the lifting efficiency of a large stamping production line are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of forging and stamping, and in particular relates to a servo master-slave synchronization system and a control method for a large-tonnage press. Background Art

[0002] With the development of stamping technology and production equipment for large-size stamping parts, higher requirements are placed on large-tonnage stamping machines for large-scale stamping production lines equipped with automatic feeding devices.

[0003] At present, the main transmission system of large-tonnage presses is to use a motor to drive the flywheel to run and store energy, and control the on and off of the clutch brake to make the transmission shaft drive the slider to run or stop. The motors are mostly large ordinary three-phase asynchronous motors or high-speed servo motors. Among them, ordinary three-phase asynchronous motors have poor controllability and are often used in multi-machine asynchronous intermittent production lines, while high-speed servo motors are often used in multi-machine synchronous stamping lines due to their good controllability. Due to the existence of flywheels and clutch brakes, the above transmission systems make the control accuracy, action sensitivity and energy efficiency of the presses not high, which in turn affects the overall beat and efficiency of the production line.

[0004] There are also small-tonnage presses that use servo transmission systems, but this type of transmission system cannot meet the requirements of large-tonnage presses in terms of servo motor form, servo motor parameters, servo motion control system and mechanical structure. Summary of the invention

[0005] The purpose of the present invention is to solve the defects and shortcomings in the prior art and to provide a large-tonnage press servo master-slave synchronization system and a control method.

[0006] To achieve the above-mentioned object, the technical solution adopted by the present invention is: a large-tonnage press servo master-slave synchronization system, including a master transmission system, a slave transmission system and a control system;

[0007] The main transmission system and the slave transmission system both include a power assembly and a transmission gear set, and the power assembly can drive the press slide to perform vertical reciprocating motion through the transmission gear set, thereby directly converting the torque of the power assembly into the punching force of the press;

[0008] The control system includes a control unit and a human-computer interaction platform. The control unit is used to receive signals from the human-computer interaction platform and drive the main transmission system and the slave transmission system respectively through master-slave servo drivers. The control unit is also connected to encoder signals in the main transmission system and the slave transmission system, and can compensate for operating errors of the main transmission system and the slave transmission system in real time, thereby achieving consistency in the operation of the two.

[0009] Preferably, the main transmission system includes a main servo motor and a main gear shaft arranged at the output end of the main servo motor, the main servo motor is provided with a main brake and a main motor encoder, the main gear shaft is meshed with a main synchronous gear, the main synchronous gear is meshed with a main eccentric gear through a main eccentric gear shaft at its center, the main eccentric gear is connected to a slider through a main connecting rod, and a main eccentric encoder is provided on the main eccentric gear.

[0010] Preferably, the slave transmission system includes a slave servo motor and a slave gear shaft arranged at the output end of the slave servo motor, the slave servo motor is provided with a slave brake and a slave motor encoder, the slave gear shaft is meshed with a slave synchronous gearwheel, the slave synchronous gearwheel is meshed with a slave eccentric gear shaft through the center of the slave eccentric gear, the slave eccentric gear is connected to the slider through a slave connecting rod, and the slave eccentric encoder is provided on the slave eccentric gear.

[0011] Preferably, the main transmission system and the slave transmission system are both fixedly mounted on the supporting crossbeam.

[0012] Preferably, it also includes a cooling system, wherein a cooling unit of the cooling system is connected in series with the main transmission system power component and the slave transmission system power component in sequence, and the cooling unit is also connected to the temperature sensor signals on the main transmission system power component and the slave transmission system power component.

[0013] Preferably, the gears in the main transmission system transmission gear set and the slave transmission system transmission gear set are herringbone gears.

[0014] A control method for the above-mentioned large-tonnage press servo master-slave synchronization system comprises the following steps:

[0015] S1. The human-computer interaction platform sends the press motion curve parameters;

[0016] S2, the control unit receives the signal from the human-machine interaction platform and processes it, converts it into a speed command and sends it to the master-slave servo driver to drive the master-slave servo motor to run according to the planned path;

[0017] S3, the master-slave motor encoder feeds back the position and speed signals of the master-slave servo motor to the master-slave servo driver in real time for calculation and comparison, and feeds back the real-time torque of the master-slave servo motor to the control unit;

[0018] S4. The control unit processes and calculates the real-time torque error between the master and slave servo motors, adjusts the speed command of the slave servo motor, and ensures the consistency of the real-time torque between the master and slave servo motors.

[0019] Preferably, in step S3, the master and slave eccentric encoders simultaneously feed back the real-time angles of the master and slave eccentric gear shafts to the control unit, which are compared with the planned path in real time to compensate for the errors in real time.

[0020] After adopting the above technical solution, the large-tonnage press servo master-slave synchronization system and control method provided by the present invention have the following beneficial effects:

[0021] 1) There is no flexible connection in the master-slave transmission system of the present invention, and the energy transmission is more direct than the traditional motor, flywheel and clutch structure, which can greatly improve the slider control ability of large-tonnage presses and is more flexible in cooperation with automation;

[0022] 2) The master and slave transmission gear sets of the present invention both adopt the herringbone gear meshing form, which can be used as the action reference of the driven end of the electrical control system in the initial debugging stage, correct the error generated by the electrical control, and ensure the synchronization of the movement between the left and right connecting rods from the mechanical structure;

[0023] 3) The master-slave gear shaft of the present invention is the rotor shaft of the master-slave servo motor, which is different from the existing small-tonnage press servo transmission system which generally adopts the motor rotor shaft and gear shaft in a separate form (i.e., using a transition method such as a sleeve, spline, etc.). The beneficial effects are no torque loss, compact structure, and no risk of sleeve slippage or spline failure;

[0024] 4) The master-slave servo motor cooling system of the present invention adopts forced mixed liquid cooling to prevent performance degradation, structural deformation and other dangers. The liquid cooling circuit adopts a series connection mode, which can ensure the same temperature of the master and slave servo motors, and thus ensure the stability and uniformity of various control performances. It is different from the existing small-tonnage presses that generally adopt air cooling and water cooling. Because the cooling power, cooling effect and use scenarios of air cooling and water cooling are greatly limited, they are not suitable for large-tonnage presses in large stamping lines;

[0025] 5) Both ends of the master-slave transmission system of the present invention have independent closed-loop control systems. The master and slave axes can be used as auxiliary control devices to form a closed-loop control system to compensate for curve operation errors in real time, and can also serve as redundancy to ensure long-term stable operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the master-slave transmission system of the present invention;

[0027] Figure 2 It is a schematic diagram of gear meshing of the master-slave transmission system of the present invention;

[0028] Figure 3 A side view of a cooling system portion of the present invention;

[0029] Figure 4 is a block diagram of the control system of the present invention;

[0030] Figure 5It is a schematic diagram of the principle of the control system of the present invention.

[0031] Among them: main servo motor 1, main brake 2, main motor encoder 3, main gear shaft 4, main synchronous gear 5, slave synchronous gear 6, slave gear shaft 7, slave servo motor 8, slave brake 9, slave motor encoder 10, main eccentric gear shaft 11, main eccentric gear 12, main connecting rod 13, main eccentric encoder 14, slave eccentric gear shaft 15, slave eccentric gear 16, slave eccentric encoder 17, slave connecting rod 18, supporting beam 19, cooling system 20. DETAILED DESCRIPTION

[0032] The present invention is further described clearly and completely below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0034] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0035] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0036] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0037] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0038] like Figure 1-3 As shown, the present invention provides a large-tonnage press servo master-slave synchronization system, which includes a master transmission system, a slave transmission system and a control system.

[0039] The main transmission system and the slave transmission system both include a power assembly and a transmission gear set. The power assembly can drive the press slide to perform vertical reciprocating motion through the transmission gear set, thereby directly converting the torque of the power assembly into the punching force of the press.

[0040] Specifically, the main transmission system includes a main servo motor 1 and a main gear shaft 4 arranged at the output end of the main servo motor 1, the main gear shaft 4 is the rotor shaft of the main servo motor 1, the main servo motor 1 is provided with a main brake 2 and a main motor encoder 3, the main gear shaft 4 is meshed with a main synchronous gear 5, the main synchronous gear 5 is meshed with a main eccentric gear 12 through a main eccentric gear shaft 11 at its center, the main eccentric gear 12 is connected to a slider through a main connecting rod 13, and a main eccentric encoder 14 is provided on the main eccentric gear 12.

[0041] The slave transmission system includes a slave servo motor 8 and a slave gear shaft 7 arranged at the output end of the slave servo motor 8, the slave gear shaft 7 is the rotor shaft of the slave servo motor 8, the slave servo motor 8 is provided with a slave brake 9 and a slave motor encoder 10, the slave gear shaft 7 is meshed with the slave synchronous large gear 6, the slave synchronous large gear 6 is meshed with the slave eccentric gear 16 through the slave eccentric gear shaft 15 at the center thereof, the slave eccentric gear 16 is connected to the slider through the slave connecting rod 18, and the slave eccentric encoder 17 is provided on the slave eccentric gear 16.

[0042] Furthermore, the master transmission system and the slave transmission system are both fixedly mounted on the supporting crossbeam 19, the gears in the transmission gear set of the master-slave transmission system are all herringbone gears, the master-slave synchronous gearwheels 5, 6 and the master-slave eccentric gear shafts 11, 15 are connected in a spline form, which is conducive to the self-adjustment of the above-mentioned herringbone tooth meshing, the angle conversion method of the master-slave eccentric encoders 14, 17 and the master-slave eccentric gears 12, 16 is gear pair transmission, and the rigid transmission method can ensure the accuracy of the angle signal, and the master-slave connecting rods 13, 18 can be composed of a multi-link system composed of other multiple connecting rods, thereby realizing the ability to further increase the slider stroke and increase the output torque.

[0043] The control system includes a control unit and a human-computer interaction platform. The control unit is used to receive signals from the human-computer interaction platform and drive the main transmission system and the slave transmission system respectively through master-slave servo drivers. The control unit is also connected to the signals of the master and slave motor encoders 3, 10 and the master and slave eccentric encoders 14, 17 in the main transmission system and the slave transmission system, and can compensate for the operating errors of the main transmission system and the slave transmission system in real time, thereby achieving consistency in the operation of the two.

[0044] It also includes a cooling system 20, wherein a cooling unit of the cooling system 20 is connected in series with a main transmission system power assembly and a slave transmission system power assembly in sequence, and the cooling unit is also connected with temperature sensor signals on the main transmission system power assembly and the slave transmission system power assembly. Specifically, the housings of the master and slave servo motors 1 and 8 are provided with channels for coolant, and the cooling system 20 adopts a series connection method to merge the master and slave servo motors 1 and 8 into the same pipeline. During specific operation: the cooling unit pumps out coolant first into the cooling inlet of the main servo motor 1, then flows out through the cooling outlet of the main servo motor 1 into the cooling inlet of the slave servo motor 8, and finally flows back to the cooling unit from the cooling outlet of the slave servo motor 8. Temperature sensors are provided on the master and slave servo motors 1 and 8 to monitor the temperatures of the master and slave servo motors in real time and automatically turn on or off the cooling unit. The above-mentioned liquid cooling medium should be a mixture of automotive coolant and pure water. The ratio is adjusted according to the ambient temperature to achieve an optimal and economical cooling effect.

[0045] The present invention provides a control method for the above-mentioned large-tonnage press servo master-slave synchronization system, comprising the following steps:

[0046] S1. The human-computer interaction platform sends the press motion curve parameters;

[0047] S2, the control unit receives the signal from the human-machine interaction platform and processes it, converts it into a speed command and sends it to the master-slave servo driver to drive the master-slave servo motor to run according to the planned path;

[0048] S3, the master-slave motor encoder feeds back the position and speed signals of the master-slave servo motor to the master-slave servo driver in real time for calculation and comparison, and feeds back the real-time torque of the master-slave servo motor to the control unit;

[0049] S4. The control unit processes and calculates the real-time torque error between the master and slave servo motors, adjusts the speed command of the slave servo motor, and ensures the consistency of the real-time torque between the master and slave servo motors.

[0050] Preferably, in the above step 3, the master and slave eccentric encoders simultaneously feed back the real-time angles of the master and slave eccentric gear shafts to the control unit for real-time comparison with the planned path and real-time compensation of the error.

[0051] The control system of the present invention is as follows Figure 4As shown, the whole control system adopts high-speed real-time bus to communicate with each other, with a minimum refresh cycle of 1ms. The human-machine interaction platform is user-oriented. In addition to being responsible for the compilation and storage of servo curves, it is also responsible for the control, monitoring and diagnosis of various components of the machine tool, and exchanges data with the motion and logic control unit. The motion and logic control unit, as the core of the whole electrical control system, is responsible for the coordinated control of various parts to ensure the stable operation of the whole control system. The servo drive and servo motor, as actuators, are responsible for converting the position, speed and torque instructions of the control unit into the rotation output of the motor, driving the whole transmission system to work together. The eccentric shaft position feedback encoder is used as an external auxiliary detection device to feedback the eccentric shaft angle in real time to form a fully closed-loop control system. The motor temperature control system is responsible for adjusting the coolant temperature of the servo motor to ensure that the servo motor temperature is maintained and the temperature consistency of multiple motors.

[0052] The control principle of the control system is as follows Figure 2 As shown in the figure, the human-computer interaction platform sends the motion curve parameters of the servo press, and the motion and logic control unit performs processing and calculation as the main control unit, converts them into speed instructions and sends them to the master and slave drivers, driving the master and slave servo motors to run according to the planned path. The master and slave servo motors are both equipped with multi-turn absolute encoders, which feed back the position and speed signals to the drivers in real time for calculation and comparison. At the same time, the real-time torque values ​​of the master and slave servo motors are fed back to the motion control unit through the high-speed real-time bus. After the torque error of the master and slave servo motors is integrated, the speed instruction of the slave servo motor is interpolated in real time to ensure that the torque difference between the master and slave servo motors fluctuates within the allowable range, thereby ensuring the consistency of the speed and torque of the master and slave servo motors. At the same time, the master and slave eccentric encoders also feed back the real-time angle of the eccentric shaft to the motion control unit, which is compared with the planned path in real time to compensate for the error in real time.

[0053] To sum up, the present invention provides a large-tonnage press servo master-slave synchronization system and control method, which includes a mechanical transmission part, a hybrid liquid cooling system and an electrical control system. It can make full use of the characteristics of the servo motor and its drive control system, make the large-tonnage press slider control more flexible, improve its control accuracy and movement sensitivity, and make it better coordinated with the automatic feeding system, thereby improving the production rhythm and efficiency of large-scale stamping production lines.

[0054] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A large-tonnage press servo master-slave synchronization system, characterized in that: Including main transmission system, slave transmission system and control system; The main transmission system and the slave transmission system both include a power assembly and a transmission gear set, and the power assembly can drive the press slide to perform vertical reciprocating motion through the transmission gear set, thereby directly converting the torque of the power assembly into the punching force of the press; The control system includes a control unit and a human-computer interaction platform. The control unit is used to receive signals from the human-computer interaction platform and drive the main transmission system and the slave transmission system respectively through master-slave servo drivers. The control unit is also connected to encoder signals in the main transmission system and the slave transmission system, and can compensate for operating errors of the main transmission system and the slave transmission system in real time, thereby achieving consistency in the operation of the two.

2. A large-tonnage press servo master-slave synchronization system according to claim 1, characterized in that: The main transmission system comprises a main servo motor (1) and a main gear shaft (4) arranged at the output end of the main servo motor (1); a main brake (2) and a main motor encoder (3) are arranged on the main servo motor (1); the main gear shaft (4) is meshed with a main synchronous gear (5); the main synchronous gear (5) is meshed with a main eccentric gear (12) through a main eccentric gear shaft (11) at the center thereof; the main eccentric gear (12) is connected to a slider through a main connecting rod (13); and a main eccentric encoder (14) is arranged on the main eccentric gear (12).

3. A large-tonnage press servo master-slave synchronization system according to claim 1, characterized in that: The slave transmission system comprises a slave servo motor (8) and a slave gear shaft (7) arranged at the output end of the slave servo motor (8); a slave brake (9) and a slave motor encoder (10) are arranged on the slave servo motor (8); the slave gear shaft (7) is meshed with a slave synchronous gear (6); the slave synchronous gear (6) is meshed with a slave eccentric gear (16) through a slave eccentric gear shaft (15) at its center; the slave eccentric gear (16) is connected to a slider through a slave connecting rod (18); and a slave eccentric encoder (17) is arranged on the slave eccentric gear (16).

4. A large-tonnage press servo master-slave synchronization system according to claim 1, characterized in that: The main transmission system and the slave transmission system are both fixedly mounted on the supporting crossbeam (19).

5. A large-tonnage press servo master-slave synchronization system according to claim 1, characterized in that: It also includes a cooling system (20), wherein a cooling unit of the cooling system (20) is connected in series with the main transmission system power component and the slave transmission system power component in sequence, and the cooling unit is also connected to temperature sensor signals on the main transmission system power component and the slave transmission system power component.

6. A large-tonnage press servo master-slave synchronization system according to claim 1, characterized in that: The gears in the main transmission system transmission gear set and the slave transmission system transmission gear set are all herringbone gears.

7. A control method for a large-tonnage press servo master-slave synchronization system as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: S1. The human-computer interaction platform sends the press motion curve parameters; S2, the control unit receives the signal from the human-machine interaction platform and processes it, converts it into a speed command and sends it to the master-slave servo driver to drive the master-slave servo motor to run according to the planned path; S3, the master-slave motor encoder feeds back the position and speed signals of the master-slave servo motor to the master-slave servo driver in real time for calculation and comparison, and feeds back the real-time torque of the master-slave servo motor to the control unit; S4. The control unit processes and calculates the real-time torque error between the master and slave servo motors, adjusts the speed command of the slave servo motor, and ensures the consistency of the real-time torque between the master and slave servo motors.

8. The control method of a large-tonnage press servo master-slave synchronization system according to claim 7, characterized in that: In step S3, the master and slave eccentric encoders simultaneously feed back the real-time angles of the master and slave eccentric gear shafts to the control unit for real-time comparison with the planned path and real-time compensation of the error.

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