INTELLIGENT NUMERICALLY-CONTROLLED PRESSURE SYSTEM FOR RECIPROCATING EXTRUSION AND METHOD OF OPERATING THE SAME

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from Chinese Patent Application No. 202411903499.7, filed on Dec. 23, 2024. The content of the aforementioned application, including any intervening amendments made thereto, is incorporated herein by reference in its entirety.

TECHNICAL FIELD

This application relates to intelligent numerically-controlled pressure systems, and more particularly to an intelligent numerically-controlled pressure system for reciprocating extrusion and a method of operating the same.

BACKGROUND

Biodegradable zinc alloys require certain ductility and desired mechanical properties as supporting and fixing function for bone screw and scaffold during application, necessitating their strengthening and toughening treatment. This is achieved by employing severe plastic deformation (SPD) techniques. SPD can significantly refine grain structures and sizes, reducing the internal material microstructure to sub-micron or even nanometer scales. Consequently, it enhances both the strength and toughness of biodegradable zinc alloys. Common SPD methods include Equal-Channel Angular Pressing (ECAP), High-Pressure Torsion (HPT), and Reciprocating Extrusion (also known as Cyclic Extrusion Compression, CEC). Among them, Reciprocating Extrusion allows for convenient adjustment of processing parameters, such as the number of extrusion passes, extrusion temperature and extrusion speed, to achieve the optimal microstructural refinement effect of materials.

Chinese patent publication No. 110919006A, entitled “A controllable back-pressure metal powder equal-channel angular extrusion device and method” and Chinese patent publication No. 110125203A, entitled “A mold-reciprocating extrusion device for metallic materials suitable for a unidirectional four-column hydraulic press” both disclose methods involving control of parameters such as pressure and temperature during the extrusion process. However, the existing these technologies still suffer from several limitations, including confined operation space for mold clamping, difficult mold clamping or mounting and related adjustment with a set of molds, low integration level of the extrusion mechanism and the control system, complex mold structure, poor versatility and higher requirements for equipment. Moreover, these technologies fail to achieve the real-time monitoring and control of the overall extrusion process, and are thus not suitable for the large-scale industrial production. The prior art also fails to achieve visualized monitoring and human-computer interaction interface for given information of the coordination of multiple physical control parameters such as pressure, temperature, speed and displacement as well as corresponding concerted feedback information aforementioned. As a result, it is difficult to scientifically determine the state of biodegradable zinc alloys during the extrusion process and achieve the precise forming control.

SUMMARY

An object of the disclosure is to provide an intelligent numerically-controlled pressure system for reciprocating extrusion and a method of operating the same to overcome the existing defects in the prior art. The intelligent numerically-controlled pressure system can precisely control the operation of the pressure system while simultaneously monitoring the working state and key parameters in real time through the configuration of a displacement control unit, an autonomous-leveling mechanism, and a temperature-displacement sensing and control unit by data recording and machine learning through a series of structural unit mechanisms. The intelligent numerically-controlled pressure system is highly versatile and can be readily integrated with commercially available equipment to achieve industrial-scale application.

Technical solutions of the present disclosure are described as follows.

In a first aspect, this application provides an intelligent numerically-controlled pressure system for reciprocating extrusion, comprising:

• • a mold clamping and temperature control unit;
  • a displacement control unit;
  • a base as adjustable chassis;
  • a personal computer (PC); and
  • a temperature-displacement sensing and control unit;
  • wherein the displacement control unit comprises a sliding rod; the base is provided with a sliding groove; the sliding rod is arranged in the sliding groove; the sliding rod is provided with an electric lifting mechanism and the electric lifting mechanism is fixedly provided with a mold control platform;
  • the mold clamping and temperature control unit comprises two moving rods arranged opposite to each other; and each of the two moving rods is provided with an electric translation mechanism;
  • the mold control platform is provided with a mounting groove; the two moving rods are arranged in the mounting groove; each of the two moving rods is further provided with a clamp for fixing a mold; and the clamp is provided with a temperature control mechanism and a pressure sensor;
  • the temperature-displacement sensing and control unit is oriented toward the mold;
  • the PC is communicatively connected to the mold clamping and temperature control unit, the displacement control unit, the mold control platform and the temperature-displacement sensing and control unit; and
  • an autonomous-leveling mechanism is provided in the mold control platform; and the autonomous-leveling mechanism is communicatively connected to the displacement control unit.

In some embodiments, the base is further provided with a pressure monitoring unit; and the pressure monitoring unit is electrically connected to the pressure sensor of the clamp.

In some embodiments, the autonomous-leveling mechanism is a gyroscope-based leveling mechanism.

In some embodiments, the PC is provided with a radio frequency transceiver.

In some embodiments, the number of the sliding groove is two; and the number of the sliding rod is two.

In some embodiments, the temperature-displacement sensing and control unit comprises an infrared distance sensor connected to a thermocouple.

In some embodiments, the electric lifting mechanism comprises a ring part sleeved on the mold control platform; and the ring part is provided with a roller and a motor drive device.

In some embodiments, the electric lifting mechanism comprises an electric lifting rod provided on the sliding rod.

In a second aspect, this application provides a method of operating the intelligent numerically-controlled pressure system described above, comprising:

• • (S1) setting a displacement parameter of the mold control platform in the PC; and raising or lowering, by the displacement control unit, the mold control platform to a predetermined height and subsequently moving the mold control platform forward according to the displacement parameter of the mold control platform, such that the mold control platform extends out of the base to a first designated position;
  • (S2) placing the mold on an upper surface of the mold control platform; setting a mold clamping parameter in the PC, wherein the mold clamping parameter comprises a mold clamping position and a clamping force; and raising or lowering, by the mold clamping and temperature control unit, the clamp to a second designated position according to a mold clamping position, and applying, by the clamp, a clamping force to the mold;
  • (S3) setting a displacement parameter of the mold control platform in the PC; adjusting, by the displacement control unit, the mold control platform to a third designated position based on the displacement parameter of the mold control platform, such that a press head is aligned with the mold; and leveling the mold control platform through the autonomous-leveling mechanism;
  • (S4) measuring an extrusion reduction through the temperature-displacement sensing and control unit; feeding a measured extrusion reduction back to the PC; and setting, by the PC, a reference reduction according to the measured extrusion reduction; and
  • (S5) setting an extrusion speed, an extrusion temperature and an extrusion pressure in the PC; and heating the mold to the extrusion temperature with the temperature control mechanism of the clamp;
  • maintaining the mold at the set extrusion temperature under a constant power; and
  • regulating a pressure during an extrusion process according to the extrusion pressure set in the PC followed by extrusion.

In some embodiments, leveling parameters of the autonomous-leveling mechanism comprise a leveling time of less than 180 s, an operating time required for a leveling accuracy, and a stable state maintaining period of 24 h, wherein the operating time is less than 2 min; the temperature-displacement sensing and control unit has a measurement accuracy of 0.1 mm; a heating temperature of the mold clamping and temperature control unit is 50-500° C.; and the extrusion speed is 0.001-100 mm/s.

Compared to the prior art, the present disclosure has the following beneficial effects.

The displacement control unit of the present disclosure can precisely control the position of the mold control platform and adjust the platform height according to different operating conditions. The displacement control unit accommodates a wide range of mold sizes and can move horizontally out of the press, thereby increasing the operating space for mold clamping and reducing the difficulty of mold installation and adjustment smoothly and controllably. The mold control platform is provided with the autonomous-leveling mechanism, which ensures that the upper surface of the mold control platform remains level, thereby eliminating the adverse effects of non-axial pressure. The temperature-displacement sensing and control unit of the present disclosure can accurately measure the relative positions of each part of the mold and automatically calculate the reduction, thereby simplifying the extrusion steps and reducing manual measurement errors. During the extrusion process, based on the relative changes in the positions of each part of the mold, the temperature-displacement sensing and control unit can calculate a downward pressing rate and feed the data back to the PC for real-time monitoring and control of the extrusion process.

Furthermore, the intelligent numerically-controlled pressure system provided herein is highly versatile and can be readily integrated with commercially available equipment, and is suitable for single-cylinder hydraulic presses commonly used on the market, thereby enabling the industrial-scale reciprocating extrusion of biodegradable zinc alloys.

Furthermore, the intelligent numerically-controlled pressure system provided herein enables more intelligent and convenient human-machine interaction and coordinated monitoring of deformation warning. Upon inputting predetermined parameters such as an extrusion speed, a reduction, a pressure and a pressure-holding period, the intelligent numerically-controlled pressure system provided herein executes the corresponding operations and simultaneously feeds back the displacement, real-time rate, and real-time pressure to the user with related curves and images by data processing and image conversion, thereby allowing precise monitoring of the extrusion status.

Furthermore, the intelligent numerically-controlled pressure system provided herein enables online monitoring and control through the PC, allowing the terminal device to monitor various parameters of the intelligent pressure system in real time and adjust the set parameters to achieve remote monitoring and control of the intelligent pressure system.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings described herein are merely illustrative, and are not intended to limit the scope of the disclosure. In addition, the shapes and scales of the components shown in the drawings are merely exemplary and descriptive to facilitate understanding of the present disclosure, instead of limiting the shapes or sizes of the components.

FIG. 1 is an axial side view of an intelligent numerically-controlled pressure system for reciprocating extrusion according to an embodiment of the present disclosure; and

FIG. 2 is a sectional view of the intelligent numerically-controlled pressure system according to an embodiment of the present disclosure.

In the figures: 1—mold clamping and temperature control unit; 2—displacement control unit; 3—mold control platform; 4—base; 5—personal computer (PC); 6—pressure monitoring unit; 7—mold; 8—temperature-displacement sensing and control unit; 9—press head; 10—autonomous leveling mechanism; and 11—radio frequency transceiver.

DETAILED DESCRIPTION OF EMBODIMENTS

To make those skilled in the art better understand the technical solutions of the present disclosure, the technical solutions will be described clearly and completely below in conjunction with the accompanying drawings. It is obvious that described below are merely some embodiments of the present disclosure, instead of all embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without making creative effort shall fall within the scope of the present disclosure defined by the appended claims.

It should be noted that when a component is described as being “provided on” another component, it may be directly arranged on another component or indirectly arranged on another component through an intermediate component. Similarly, when a component is described as being “connected to” another component, it may be directly connected to another component or indirectly connected with another component through an intermediate component. As used herein, the terms “vertical”, “horizontal”, “left” and “right” and similar expressions are for illustrative purposes only, and are not intended to limit the disclosure.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art. The terms used herein are merely descriptive, and are not intended to limit the disclosure. As used herein, the term “and/or” refers to any and all combinations of one or more of the listed items.

The technical solutions of the present disclosure will be described in further detail below with reference to the accompanying drawings.

As shown in FIGS. 1-2, an embodiment of the present disclosure provides an intelligent numerically-controlled pressure system for reciprocating extrusion, including a mold clamping and temperature control unit 1, a displacement control unit 2, a base 4, a personal computer (PC) 5, and a temperature-displacement sensing and control unit 8. The displacement control unit 2 includes a sliding rod. The base 4 is provided with a sliding groove. The sliding rod is arranged in the sliding groove. The sliding rod is provided with an electric lifting mechanism. The electric lifting mechanism is fixedly provided with a mold control platform 3. The mold clamping and temperature control unit 1 includes two moving rods arranged opposite to each other. Each of the two moving rods is provided with an electric translation mechanism. The mold control platform 3 is provided with a mounting groove. The two moving rods are arranged in the mounting groove. Each of the two moving rods is further provided with a clamp for fixing a mold 7. The clamp is provided with a temperature control mechanism and a pressure sensor. The temperature-displacement sensing and control unit 8 is oriented toward the mold 7. The PC 5 is communicatively connected to the mold clamping and temperature control unit 1, the displacement control unit 2, the mold control platform 3 and the temperature-displacement sensing and control unit 8. An autonomous-leveling mechanism 10 is provided in the mold control platform 3. The autonomous-leveling mechanism 10 is communicatively connected to the displacement control unit 2.

A method of using the intelligent numerically-controlled pressure system provided herein includes the following steps.

(S1) A displacement parameter of the mold control platform 3 is set in the PC 5. The mold control platform 3 is raised or lowered to a predetermined height and subsequently moved forward by the displacement control unit 2 according to the displacement parameter of the mold control platform 3, such that the mold control platform 3 extends out of the base 4 to a first designated position.

(S2) The mold 7 is placed on an upper surface of the mold control platform 3. A mold clamping parameter is set in the PC 5, where the mold clamping parameter includes a mold clamping position and a clamping force. The clamp is raised or lowered to a second designated position by the mold clamping and temperature control unit 1 according to a mold clamping position. A clamping force is applied to the mold 7 by the clamp.

(S3) A displacement parameter of the mold control platform 3 is set in the PC 5. The mold control platform 3 is adjusted to a third designated position by the displacement control unit 2 according to the displacement parameter of the mold control platform 3, such that a press head 9 is aligned with the mold 7. The mold control platform 3 is leveled by the autonomous-leveling mechanism 10.

(S4) An extrusion reduction is measured through the temperature-displacement sensing and control unit 8. A measured extrusion reduction is fed back to the PC 5. A reference reduction is set by the PC 5 according to the measured extrusion reduction.

(S5) An extrusion speed, an extrusion temperature and an extrusion pressure are set in the PC 5. The mold 7 is heated to the extrusion temperature by the temperature control mechanism of the clamp. The mold 7 is maintained at the set extrusion temperature under a constant power. A pressure is regulated during an extrusion process according to the extrusion pressure set in the PC, and extrusion is performed.

Embodiment 1

The embodiments of the present disclosure will be further described below in conjunction with FIGS. 1-2.

Provided herein is an intelligent numerically-controlled pressure system for reciprocating extrusion, including a base 4, a mold control platform 3 and a personal computer (PC) 5.

The mold control platform 3 includes a mold clamping and temperature control unit 1, a displacement control unit 2, an autonomous-leveling mechanism 10, and a temperature-displacement sensing and control unit 8.

The mold clamping and temperature control unit 1 is provided with a pressure sensor. The clamp of the mold 7 is configured to move vertically and horizontally in the three-dimensional coordinates, enabling the mold 7 to be clamped at a designated position with a designated force according to a mold clamping parameter.

The mold clamping and temperature control unit 1 is mounted on the mold control platform 3 for clamping and heating the mold 7.

In some embodiments, the mold control platform 3 is a plate part. The mold control platform 3 is provided with two mounting grooves. The mold clamping and temperature control unit 1 includes two moving rods. Each moving rod is provided in a corresponding one of the two mounting grooves of the mold control platform 3. Each of the two mounting grooves is elongated, and is configured to allow the corresponding moving rod to move along a length direction of the corresponding mounting groove and to move vertically. Each moving rod is provided with an electric translation mechanism. In some embodiments, the electric translation mechanism is a motor drive roller.

Each of the moving rods is provided with a clamp. In some embodiments, the two moving rods are provided on the same axis and arranged opposite to each other. Two clamps are mounted on the opposite surfaces of the two moving rods. In some embodiments, the two clamps are detachable and replaceable.

The base 4 is connected to the mold control platform 3 via the displacement control unit 2. An upper end of the base 4 is provided with a pressure monitoring unit 6 and the PC 5. The PC 5 is provided with a radio frequency transceiver 11.

In some embodiments, the PC 5 is an intelligent touch-controlled PC.

The pressure monitoring unit 6 is electrically connected to the mold clamping and temperature control unit 1 for monitoring a pressure of the mold 7. Specifically, the mold clamping and temperature control unit 1 is provided with a pressure sensor, enabling the clamp to clamp the mold 7 at a designated position with a designated force according to a mold clamping parameter. The pressure monitoring unit 6 is a pressure display mechanism electrically connected to the pressure sensor.

The displacement control unit 2 is fixedly mounted on two sides of the mold control platform 3 for moving and positioning the mold control platform 3.

In some embodiments, the base 4 is provided with two sliding grooves. The two sliding grooves are elongated.

In some embodiments, the displacement control unit 2 includes two sliding rods. Each of the two sliding rods is provided in a corresponding one of the two sliding grooves of the base 4. Each of the two sliding rods is configured to slide along the corresponding sliding groove. In some embodiments, a bottom of each sliding rod is provided with a roller and a motor drive mechanism.

In some embodiments, two sides of the mold control platform 3 are each fixedly provided with a ring part. The ring part is sleeved on the corresponding sliding rod. The ring part is provided with a roller and a motor drive mechanism, and is configured to move vertically along the corresponding sliding rod.

In some embodiments, the sliding rods of the displacement control unit 2 are configured as electric lifting rods.

The autonomous-leveling mechanism 10 is provided within the mold control platform 3 for adjusting and maintaining the level of the mold control platform 3. The autonomous-leveling mechanism 10 is communicatively connected to the displacement control unit 2. In some embodiments, the autonomous-leveling mechanism 10 is a gyroscope-based leveling mechanism.

The temperature-displacement sensing and control unit 8 is fixed on the mold control platform 3 and oriented toward the mold 7. In some embodiments, the temperature-displacement sensing and control unit 8 is fixed on a rear side of the mold control platform 3 for determining the temperatures and relative positions of each part of the mold 7.

In some embodiments, the temperature-displacement sensing and control unit 8 includes an infrared distance sensor for real-time monitoring of the temperatures of each part of the mold 7. The infrared distance sensor is connected to a thermocouple to monitor an internal temperature of the mold 7. The temperature-displacement sensing and control unit 8 is configured to move vertically, and is further configured to monitor the relative positions of each part of the mold 7 based on changes in readings of the infrared distance sensor during the vertical movement, thereby determining a reduction.

The mold clamping and temperature control unit 1, the pressure monitoring unit 6, the autonomous-leveling mechanism 10 and the temperature-displacement sensing and control unit 8 are configured to monitor the temperature of the mold 7, the extrusion speed, and the extrusion pressure during the extrusion process, and feed the data back to the PC 5. The PC 5 is configured to compare the current parameters with the set parameters and performs real-time compensation accordingly.

Embodiment 2

Provided herein is a method of operating an intelligent numerically-controlled pressure system for reciprocating extrusion, including the following steps.

A displacement parameter of a mold control platform 3 is set in a personal computer (PC) 5. The mold control platform 3 is raised or lowered to a predetermined height and subsequently moved forward by a displacement control unit 2 according to the displacement parameter of the die control platform 3, such that the mold control platform 3 extends out of the base to a first designated position, with a displacement setting accuracy of 0.1 mm.

A mold 7 is placed on an upper surface of the mold control platform 3. A mold clamping parameter is set in the PC 5, where the mold clamping parameter includes a mold clamping position and a clamping force. A clamp is raised or lowered to a second designated position by the mold clamping and temperature control unit 1 according to a mold clamping position. A clamping force is applied to the mold 7 by the clamp.

A displacement parameter of the mold control platform 3 is set in the PC 5. The mold control platform 3 is adjusted to a third designated position by displacement control unit 2 according to the displacement parameter of the mold control platform 3, such that a press head 9 is aligned with the mold 7. Subsequently, the mold control platform 3 is leveled by an autonomous-leveling mechanism 10 provided in the mold control platform 3 based on a surface levelness of the mold control platform 3, with leveling parameters of a leveling time less than 180 s, an operating time required for a leveling accuracy, and a stable holding period of 24 h, where the operating time is less than 2 min.

An extrusion reduction is measured by a temperature-displacement sensing and control unit 8 with a measurement accuracy of 0.1 mm. A measured extrusion reduction is fed back to the PC 5. A reference reduction is set by the PC 5 according to the measured extrusion reduction. An extrusion speed, an extrusion temperature and an extrusion pressure are set in the PC 5. The mold is heated to the set extrusion temperature by the mold clamping and temperature control unit 1, with a heating temperature of 50-500° C. The mold 7 is maintained at the set extrusion temperature under a constant power.

A pressure is regulated during an extrusion process by a pressure monitoring unit 6 according to the extrusion pressure set in the PC 5, with the pressure of 0-150 T and an extrusion speed of 0.001-100 mm/s. Then, extrusion is performed.

Furthermore, the method provided herein enables real-time monitoring and recording of the extrusion pressure, the extrusion reduction, the extrusion speed and the extrusion temperature. The temperature-displacement sensing and control unit 8 is configured to monitor the temperatures and relative positions of each part of the mold 7 in real time and return the data to the PC 5, thereby automatically calculating the extrusion reduction and controlling the mold clamping and temperature control unit 1 to heat the mold 7.

During extrusion, the reduction is continuously measured in real time by the temperature-displacement sensing and control unit 8, and a pressing rate is output to the PC 5. In this process, the collected data are compared with preset values by the PC 5, and deviation compensation is performed. The collected data are integrated by the PC 5 to generate pressure-displacement, temperature-time, and pressure-speed curves, which are transmitted in real time via a radio frequency transceiver 11 to the touchscreen display interface and user terminals on the local area network. Meanwhile, modification information of the preset values is received from the user terminals on the local area network and transmitted to the PC 5, thereby enabling online monitoring and control of the intelligent numerically-controlled pressure system for reciprocating extrusion.

Unless otherwise specified, the device components involved in the above embodiments are conventional components, and the structural arrangements, operating modes and control methods involved are all conventional in the art.

It should be noted that the described embodiments are merely illustrative, and are not intended to limit the scope of the present disclosure. It should be understood that various modifications, changes and replacements made by those skilled in the art without departing from the spirit of the disclosure shall fall within the scope of the present disclosure defined by the appended claims.