Self-resistance heating floating type sectional material stretch bending jaw device
By using a self-resistance heating floating profile bending jaw device, combined with a multi-lobed jaw wedge block and an insulating cooling unit, precise heating and cooling control of the jaws is achieved. This solves the problems of surface cracking, work hardening, and low heating efficiency of jaw devices in high-strength profile forming, thereby improving forming accuracy and reducing energy consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INTELLIGENT AEROSPACE MFG TECH BEIJING CO LTD
- Filing Date
- 2026-03-30
- Publication Date
- 2026-05-12
AI Technical Summary
Existing jaw devices suffer from problems such as high forming force leading to surface cracking, severe work hardening, high friction loss, low heating efficiency, and poor thermal management in the stretch bending forming of high-strength titanium alloy and aluminum alloy profiles. Furthermore, traditional heating equipment is energy-intensive, occupies a large area, and is difficult to control precisely.
The device employs a self-resistance heating floating profile bending jaw device, which combines a multi-lobed jaw wedge block, a conical drive sleeve, a telescopic cylinder, a self-resistance heating element, and an insulating cooling unit to achieve integrated clamping, heating, and cooling of the jaws. The heating and cooling processes are precisely controlled through a PID algorithm.
It effectively reduces stress concentration and springback in the profile clamping area, improves forming accuracy and surface quality, enhances heating control accuracy and efficiency, and reduces manufacturing costs and energy consumption.
Smart Images
Figure CN122007221A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of metal profile plastic forming equipment, specifically relating to a self-resistance heating floating profile bending clamp device suitable for titanium alloy and aluminum alloy materials. Background Technology
[0002] Currently, the jaws used in the stretch bending forming process of high-strength titanium alloys, aluminum alloys, and other profiles are mostly traditional hydraulically driven mechanical jaws. These jaws have the following significant drawbacks: ① Due to their large forming force, surface cracking and internal damage are easily caused when the material is in a low-temperature, low-plasticity state. ② Significant work hardening occurs in the contact area between the profile and the jaws, making material springback difficult to predict and control. ③ When the material is not heated or heated unevenly, frictional wear between the jaws and the profile is aggravated, severely affecting service life. On the other hand, the integral furnaces or induction heating equipment used in stretch bending forming under heating conditions suffer from high energy consumption, low heating efficiency, difficulty in precisely controlling the heating process, and large equipment footprint. Furthermore, the lack of effective thermal management methods for the contact area is also a significant factor contributing to localized stress concentration and poor surface quality in the profiles. Summary of the Invention
[0003] In view of this, and in response to the technical problems existing in this field, the present invention provides a self-resisting heating floating profile bending jaw device, comprising: a multi-lobed jaw wedge block, a wedge block base, a conical drive sleeve, a telescopic cylinder, a self-resisting heating element, and an insulating cooling unit. The tapered drive sleeve has a smaller front opening and a larger rear opening. The jaw wedge block is located inside the tapered drive sleeve, with its outer surface in close contact with the inner tapered surface of the tapered drive sleeve, and its inner surface serving as the profile clamping surface. The rear end of the jaw wedge block is connected to a wedge block base, which is fixedly connected to the front end of the piston rod of the telescopic cylinder. The cylinder body of the telescopic cylinder is fixedly connected to the tapered drive sleeve. Driven by the telescopic cylinder, the jaw wedge block can move back and forth along the inner tapered surface of the tapered drive sleeve, and its rear end slides radially on the surface of the wedge block base, thereby realizing the clamping and opening action of the jaws. A self-resistance heating element is installed near the clamping surface of the jaw wedge block for self-resistance heating when the jaws are closed to clamp the profile. An insulating cooling unit is installed on the outer conical surface of the conical drive sleeve and is connected to the cooling channel set in the jaws and the external cooling source to form a circulating cooling system. The cooling medium enters the jaws from the inlet of the cooling channel, absorbs heat, flows out from the outlet of the cooling channel and returns, which is used to cool the profile.
[0004] Furthermore, guide pins are provided on both the outer and rear surfaces of the jaw wedge block, and corresponding axial guide grooves and radial floating grooves are provided on the tapered drive sleeve and the wedge block base, respectively, to cooperate in realizing the sliding guidance and limiting of the jaw wedge block and reduce unnecessary movement.
[0005] Furthermore, the jaw wedge block can be configured with a suitable number of lobes and a single-lobe structure as needed, such as a specific configuration of 3 lobes distributed at 120°, where two lobes form the upper jaw mold and the other lobe serves as the lower jaw mold.
[0006] Furthermore, the self-resistance heating element uses a heating wire or heating plate and is connected to an external programmable heating power supply through an electrode interface to perform heating control according to a set temperature rise curve.
[0007] Furthermore, the device is also equipped with pressure sensors and thermocouples, with their measuring points set on the jaw wedge blocks to detect clamping force and profile temperature; a displacement sensor is also provided to detect jaw gap and profile deformation.
[0008] Furthermore, the rear end of the telescopic cylinder is connected to the actuating mechanism and the machine tool mounting base of the profile bending equipment via an insulating and heat-insulating seat. The machine tool mounting base is also equipped with corresponding insulating and heat-insulating elements to prevent heat from being conducted to the machine tool and affecting its accuracy and lifespan.
[0009] Accordingly, the present invention also provides a profile bending forming method performed using the above-mentioned self-resistance heating floating profile bending jaw device, comprising the following steps: Step 1: Input parameters such as profile material, cross-sectional dimensions, and target bending angle; Step 2: Based on the material thermoplasticity data and finite element simulation, determine the optimal forming temperature window T, heating time t, cooling rate v, etc. Step 3: Set initial parameters, including: heating power P_init = U×I (U is voltage, I is initial current), clamping force F = 10-50 kN (calculated based on profile cross-section); Step 4: Clamp the jaws and perform a stretching operation. During this process, based on the deviation ΔT between the real-time temperature T fed back by the thermocouple and the set temperature T, adjust the current output using a PID algorithm. The current output value I... adjust Based on the following formula, I is obtained: adjust = K p ×ΔT + K i ∫ΔTdt + K d d(ΔT) / dt; where K p K i K d All are PID control parameters; Step 5: After the profile is formed, adjust the coolant flow rate Q according to the set cooling rate v to cool the profile to below room temperature. Step 6: Once forming is complete, release the profile and remove it.
[0010] Furthermore, step 2 also includes setting the springback compensation amount based on the simulation results, specifically calculated according to the preset bending amount Δθ; Δθ can be calculated using empirical formulas about material properties, forming temperature, and bending radius: Δθ = f(material properties, forming temperature, bending radius).
[0011] The self-resistance heating floating profile bending jaw device provided by the present invention can effectively reduce local stress concentration and springback in the profile clamping area through the floating progressive multi-lobed jaw design, which helps to improve forming accuracy and profile surface quality. It innovatively integrates heating and cooling functions with the jaw, which can effectively improve heating control accuracy and efficiency and replace traditional large-scale heating and temperature control equipment such as integrated furnaces. It has significant advantages in terms of manufacturing cost and energy consumption. Attached Figure Description
[0012] Figure 1 This is an overall structural diagram of the self-resistance heating floating profile bending jaw device provided by the present invention; Figure 2 An exploded view of the self-resistance heating floating profile bending jaw device provided by the present invention; Figure 3 Optional structural diagram of a machine tool mounting base for connection to a jaw assembly; Figure 4 Diagram showing optional installation methods for insulating and heat-resistant components on machine tool mounting bases. Detailed Implementation
[0013] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0014] The self-resistance heating floating profile bending jaw device provided by this invention, such as Figure 1 , 2 As shown, it includes: a multi-lobed jaw wedge block 1, a wedge block base 2, a conical drive sleeve 3, a telescopic cylinder 4, a self-resisting heating element 5, and an insulating cooling unit 6. The tapered drive sleeve 3 has a smaller front opening and a larger rear opening. The jaw wedge block 1 is located inside the tapered drive sleeve 3, with its outer surface in close contact with the inner tapered surface of the tapered drive sleeve 3, and its inner surface serving as the profile clamping surface. The rear end of the jaw wedge block 1 is connected to a wedge block base 2, which is fixedly connected to the front end of the piston rod 7 of the telescopic cylinder 4. The cylinder body 8 of the telescopic cylinder 4 is fixedly connected to the tapered drive sleeve 3. Driven by the telescopic cylinder 4, the jaw wedge block can move back and forth along the inner tapered surface of the tapered drive sleeve, and its rear end slides radially on the surface of the wedge block base 2, thereby realizing the closing and opening of the jaws. A self-resistance heating element 5 is provided near the clamping surface of the jaw wedge block 1 for self-resistance heating when the jaws are closed to clamp the profile; an insulating cooling unit 6 is provided on the outer conical surface of the conical drive sleeve 3 and is connected to the cooling channel provided in the jaws and the external cooling source to form a circulating cooling system. The cooling medium enters the jaws from the cooling channel inlet 9, absorbs heat and flows out from the cooling channel outlet 10 and returns, which is used to cool the profile.
[0015] In a preferred embodiment of the present invention, guide pins are provided on both the outer surface and the rear surface of the jaw wedge block 1, and corresponding axial guide grooves and radial floating grooves are provided on the tapered drive sleeve 3 and the wedge block base 2, respectively, to cooperate in realizing the sliding guidance and limiting of the jaw wedge block 1 and reducing unnecessary movement.
[0016] In a preferred embodiment of the present invention, the jaw wedge block 1 can be selected with a suitable number of lobes and a single-lobe structure as needed, for example, specifically including a form in which 3 lobes are distributed at 120°, wherein two lobes form the upper jaw mold and the other lobe serves as the lower jaw mold.
[0017] In a preferred embodiment of the present invention, the self-resisting heating element 5 is a heating wire or heating plate, which is connected to an external programmable heating power supply through an electrode interface to perform heating control according to a set temperature rise curve.
[0018] In a preferred embodiment of the present invention, the device is further provided with a pressure sensor and a thermocouple, the measuring points of which are all set on the jaw wedge block 1 for detecting the clamping force and the profile temperature; a displacement sensor is also provided for detecting the jaw gap and the profile deformation.
[0019] In a preferred embodiment of the present invention, the rear end of the telescopic cylinder 4 is connected to the actuating mechanism and the machine tool mounting base 12 of the profile bending equipment via an insulating and heat-insulating seat 11. The machine tool mounting base 12 is also provided with corresponding insulating and heat-insulating elements to prevent heat from being conducted to the machine tool and affecting its accuracy and lifespan. Figure 3 , 4 The optional configurations of the machine tool mounting base 12 and the corresponding insulation and heat insulation elements are shown respectively.
[0020] When using the above-mentioned device to perform the profile bending process, the jaw action and heating and cooling process include: First, the titanium alloy, aluminum alloy, or other material to be formed is placed in the jaws. The telescopic cylinder is controlled to push the wedge block base and the jaw wedge block forward. At the same time, the jaw wedge block is radially contracted and closed under the pressure of the inner surface of the conical drive sleeve. Once any jaw wedge block contacts the profile, its radial movement is restricted. The jaws of other profiles that are not in contact with the profile continue to contract radially until they are in complete contact with the profile and clamp it with a precise clamping force.
[0021] Afterwards, the telescopic cylinder maintains the preset clamping force, and the self-resistance heating unit is activated to generate local heat in the contact area between the jaws and the clamped profile, reaching the target forming temperature according to the preset heating curve.
[0022] At the target forming temperature, the machine tool's stretching mechanism performs the stretching action. During this process, the system adjusts the heating power based on the detection data of pressure, temperature, and displacement, and utilizes an insulated cooling unit to provide the optimal temperature for the deformation zone. After stretching and forming, the clamping force is maintained for a certain period of time, during which time the insulated cooling unit performs forced cooling to rapidly reduce the profile temperature to below room temperature, thereby achieving shaping and suppressing springback.
[0023] Finally, the forming process ends, the telescopic cylinder depressurizes and retracts, the jaw wedge blocks move backward and radially separate to reach the initial gap, and the formed workpiece is removed.
[0024] Accordingly, the present invention also provides a profile bending forming method performed using the above-mentioned self-resistance heating floating profile bending jaw device, comprising the following steps: Step 1: Input parameters such as profile material, cross-sectional dimensions, and target bending angle; Step 2: Based on the material thermoplasticity data and finite element simulation, determine the optimal forming temperature window T, heating time t, cooling rate v, etc. Step 3: Set initial parameters, including: heating power P_init = U×I (U is voltage, I is initial current), clamping force F = 10-50 kN (calculated based on profile cross-section); Step 4: Clamp the jaws and perform a stretching operation. During this process, based on the deviation ΔT between the real-time temperature T fed back by the thermocouple and the set temperature T, adjust the current output using a PID algorithm. The current output value I... adjust Based on the following formula, I is obtained: adjust = K p ×ΔT + K i ∫ΔTdt + K d d(ΔT) / dt; where K p K i Kd All are PID control parameters; Step 5: After the profile is formed, adjust the coolant flow rate Q according to the set cooling rate v to cool the profile to below room temperature. Step 6: Once forming is complete, release the profile and remove it.
[0025] In a preferred embodiment of the present invention, step 2 further includes setting a springback compensation amount based on simulation results, specifically calculated according to a preset bending amount Δθ; Δθ can be calculated using an empirical formula regarding material properties, forming temperature, and bending radius: Δθ = f(material properties, forming temperature, bending radius).
[0026] In the description of this invention, it should be noted that the terms "front", "rear", "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0028] It should be understood that the sequence number of each step in the embodiments of the present invention does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A self-resistance heating floating profile bending clamp device, characterized in that: It includes a multi-lobed jaw wedge block, a wedge block base, a conical drive sleeve, a telescopic cylinder, a self-resisting heating element, and an insulating cooling unit; The tapered drive sleeve has a smaller front opening and a larger rear opening. The jaw wedge block is located inside the tapered drive sleeve, with its outer surface in close contact with the inner tapered surface of the tapered drive sleeve, and its inner surface serving as the profile clamping surface. The rear end of the jaw wedge block is connected to a wedge block base, which is fixedly connected to the front end of the piston rod of the telescopic cylinder. The cylinder body of the telescopic cylinder is fixedly connected to the tapered drive sleeve. Driven by the telescopic cylinder, the jaw wedge block can move back and forth along the inner tapered surface of the tapered drive sleeve, and its rear end slides radially on the surface of the wedge block base, thereby realizing the clamping and opening action of the jaws. A self-resisting heating element is installed near the clamping surface of the jaw wedge block; an insulating cooling unit is installed on the outer conical surface of the conical drive sleeve and is connected to the cooling channel set in the jaw and the external cooling source to form a circulating cooling system.
2. The self-resistance heating floating profile bending jaw device as described in claim 1, characterized in that: Guide pins are provided on the outer and rear surfaces of the jaw wedge block, and corresponding axial guide grooves and radial floating grooves are provided on the tapered drive sleeve and the wedge block base, respectively.
3. The self-resistance heating floating profile bending jaw device as described in claim 1, characterized in that: The jaw wedge block is specifically designed with three lobes distributed at 120°.
4. The self-resistance heating floating profile bending jaw device as described in claim 1, characterized in that: The self-resistance heating element uses a heating wire or heating plate and is connected to an external programmable heating power supply through an electrode interface to perform heating control according to a set temperature rise curve.
5. The self-resistance heating floating profile bending clamp device as described in claim 1, characterized in that: The device is also equipped with pressure sensors and thermocouples, with their measuring points set on the jaw wedge blocks to detect clamping force and profile temperature; a displacement sensor is also installed to detect jaw gap and profile deformation.
6. The self-resistance heating floating profile bending jaw device as described in claim 1, characterized in that: The rear end of the telescopic cylinder is connected to the actuating mechanism and the machine tool mounting base of the profile bending equipment via an insulating and heat-insulating seat. The machine tool mounting base is also equipped with corresponding insulating and heat-insulating elements.
7. A method for forming profiles by means of a self-resistance heating floating profile bending jaw device as described in any one of claims 1-6, characterized in that: Includes the following steps: Step 1: Input the profile material, cross-sectional dimensions, and target bending angle parameters; Step 2: Based on the material thermoplasticity data and finite element simulation, determine the optimal forming temperature window T, heating time t, and cooling rate v; Step 3: Set initial parameters, including heating power and clamping force; Step 4: Clamp the jaws and perform a stretching operation. During this process, based on the deviation ΔT between the real-time temperature T fed back by the thermocouple and the set temperature T, adjust the current output using a PID algorithm. The current output value I... adjust Based on the following formula, I is obtained: adjust = K p ×ΔT+ K i ∫ΔTdt + K d d(ΔT) / dt; where K p K i K d All are PID control parameters; Step 5: After the profile is formed, adjust the coolant flow rate Q according to the set cooling rate v to cool the profile to below room temperature. Step 6: Once forming is complete, release the profile and remove it.
8. The method as described in claim 7, characterized in that: Step 2 also includes setting the springback compensation amount based on the simulation results, specifically calculated according to the preset bending amount Δθ; Δθ is specifically calculated using empirical formulas about material properties, forming temperature, and bending radius.