CN112338035A

CN112338035A - Hot drawing forming device and method capable of controlling blank holder force

Info

Publication number: CN112338035A
Application number: CN202011180692.4A
Authority: CN
Inventors: 杨柳; 李璐璐
Original assignee: Yanshan University
Current assignee: Yanshan University
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-02-09

Abstract

The invention discloses a hot drawing forming device and method capable of controlling blank holder force, and relates to the field of hot stamping forming of plates, wherein the forming device comprises a male die, a female die, a blank holder and the like; the use method is that the driving force of the servo motor is transmitted and converted through the speed reducer and the lead screw to provide the blank holder force, the relation between the torque of the motor and the blank holder force is established according to the equal interval numerical value, the torque of the motor is adjusted, and then the adjustment of the blank holder force is realized. Compared with the prior art, the hot drawing forming device provided by the invention has the advantages of simple and compact structure, high space utilization rate and low processing cost, and can be installed and fixed on various devices; the servo motor drives the speed reducer to provide blank pressing force, so that the control precision is high, the real-time adjustment can be realized, the noise and the energy consumption are low, and the application range is wide; different hot stamping performance tests can be realized by replacing the punch and the die; the hot drawing forming method provided by the invention has the advantages that the parameters are set through a servo motor driver panel or driver software, the form is simple, the mastering is easy, and the operability is strong.

Description

Hot drawing forming device and method capable of controlling blank holder force

Technical Field

The invention relates to the technical field of hot stamping and forming of metal plates, in particular to a hot drawing and deep forming device and method capable of controlling blank holder force.

Background

In the hot drawing and deep forming process of the metal plate, the problem of interactive influence of a plurality of factors such as temperature, blank holder force, deep drawing speed, geometric dimension of a die and the like exists. The blank holder force is an important process parameter influencing the smoothness of drawing forming, and the occurrence of crinkling, cracking and other fatal defects in the hot drawing process can be furthest inhibited by effectively controlling the blank holder force, so that the production efficiency of drawn parts and the product percent of pass are obviously improved.

At present, a method for controlling blank pressing force in a hot drawing forming process mainly adopts a hydraulic power supply mode, and the method has the defects of low blank pressing force control precision, poor thermal stability, large occupied space of a device, easiness in oil leakage, complex system and the like. Therefore, how to provide a new hot-drawing forming device and method to overcome the above problems is a problem to be solved by the present invention.

Disclosure of Invention

The invention aims to provide a hot drawing forming device and method capable of controlling edge pressing force, and the device is simple and reasonable in structure, accurate in edge pressing force control, strong in operability and high in production efficiency.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a hot drawing forming device with controllable blank holder force, which specifically comprises:

the forming die comprises a concave die plate, a die and a die holder, wherein the concave die plate is provided with a concave die, and the concave die is used for placing a plate to be formed;

the upper pressing edge plate is arranged above the concave die plate and is used for installing a pressing edge ring and a convex die matched with the concave die; the male die penetrates through the blank holder and can perform telescopic motion relative to the blank holder under the drive of power;

the displacement adjusting mechanism is used for adjusting the position of the blank pressing edge plate under the control of the driver panel so that the blank pressing ring presses the plate and regulates and controls the blank pressing force;

the female die and/or the blank holder are/is provided with a heating rod and/or a temperature sensor, and the heating rod and/or the temperature sensor are/is in signal connection with the driver panel.

Optionally, the die further comprises a blank holder lower plate, wherein the blank holder lower plate is positioned below the cavity plate and is fixedly connected with the blank holder upper plate through a pull rod; the displacement adjusting mechanism is directly connected with the blank pressing lower plate.

Optionally, a guide pillar is connected to the lower portion of the cavity plate, and the blank-holding lower plate is slidably sleeved on the guide pillar.

Optionally, the displacement adjusting mechanism includes a ball screw and a screw nut, one end of the ball screw is connected to the driving motor, the screw nut is in threaded connection with the ball screw, and the screw nut is fixedly connected to the blank holding lower plate.

Optionally, the driving motor is in signal connection with the driver panel.

Optionally, the top end of the male die is externally connected with a test device for providing power for the extension and retraction of the male die.

Optionally, a force sensor for calibrating the blank holder force is configured on the female die, and the force sensor is in signal connection with the driver panel.

Meanwhile, the invention provides a hot drawing forming method based on the controllable blank holder force of the hot drawing forming device, which comprises the following steps:

the method comprises the following steps: switching on the power supply of the driver panel, and setting a torque mode in the driver panel by using software or manually;

step two: the motor torque required for reaching the blank holder force is estimated by using formula back calculation;

step three: after the motor torque obtained by the reverse calculation and estimation is set, calibrating by using a force sensor, and determining the relation between the blank holder force and the motor torque according to the equal interval numerical value;

step four: placing a plate to be drawn on the female die, driving the blank holder to move to the position above the plate through the displacement adjusting mechanism, and stopping after a gap is reserved;

step five: switching on a switch of a temperature controller, setting heating temperature and starting heating;

step six: after the heating temperature is reached, setting the blank holder force according to the relation between the blank holder force and the motor torque in the third step, and starting the displacement adjusting mechanism again to enable the blank holder to move downwards to press the plate and keep constant downward pressure;

step seven: and the male die moves downwards under the control of external test equipment until drawing is finished.

Compared with the prior art, the invention has the following technical effects:

compared with the prior art, the invention has the following beneficial effects:

(1) the hot drawing forming device with controllable blank holder force provided by the invention has the advantages of simple and compact structure, high space utilization rate and low processing cost, and can be installed and fixed on various devices;

(2) the hot drawing forming device with the controllable blank holder force, provided by the invention, is driven by the motor to provide the blank holder force, is high in control precision, can be adjusted in real time, and is low in noise and energy consumption and wide in application range;

(3) the hot drawing forming device with controllable blank holder force can realize different hot stamping performance (bulging, cupping and the like) tests by replacing the male die and the female die;

(4) the hot drawing forming method of the controllable blank holder force provided by the invention has the advantages that the parameters are set through the servo motor and the driver panel or the driver software, the form is simple, the mastering is easy, and the operability is strong.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic structural diagram a of a hot-drawing forming apparatus with controllable blank holder force according to the present invention;

FIG. 2 is a schematic structural diagram b of a hot-drawing forming apparatus with controllable blank holder force according to the present invention;

FIG. 3 is a front view of a blank holder of the present invention;

FIG. 4 is a top view of a blank holder of the present invention;

FIG. 5 is a schematic view of the structure of the male mold of the present invention;

FIG. 6 is a top view of the female mold of the present invention;

FIG. 7 is a full sectional view taken along line A-A of FIG. 6;

FIG. 8 is a schematic view of the construction of the cavity plate of the present invention;

FIG. 9 is a schematic view of the construction of the guide cylinder of the present invention;

FIG. 10 is a schematic view of the structure of the guide post of the present invention;

FIG. 11 is a schematic view of the construction of the heat shield of the present invention;

FIG. 12 is a schematic view of a heater bar according to the present invention;

FIG. 13 is a front view of the pull rod of the present invention;

FIG. 14 is a schematic view of the lead screw fixing base according to the present invention;

FIG. 15 is a schematic view of a screw supporting base according to the present invention;

FIG. 16 is a schematic view of the construction of the lower template of the present invention;

FIG. 17 is a schematic view of the construction of the upper platen of the present invention;

FIG. 18 is a schematic view of a blank holder lower plate according to the present invention;

FIG. 19 is a schematic view of the support of the present invention;

FIG. 20 is a schematic view of a heating system of the present invention;

wherein the reference numerals are: 1-round nut, 2-lower template, 3-reducer, 4-support frame, 5-guide post, 6-linear bearing a, 7-blank holder plate, 8-ball screw, 9-concave template, 10-linear bearing b, 11-pull rod, 12-blank holder, 13-blank holder upper plate, 14-male mold, 15-guide cylinder, 16-heat insulation plate, 17-female mold, 18-screw, 19-screw support seat, 20-screw nut, 21-screw fixing seat and 22-motor.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

The first embodiment is as follows:

as shown in fig. 1 to 20, the embodiment provides a hot-drawing forming device with controllable blank holder force, which mainly includes a round nut 1, a lower die plate 2, a speed reducer 3, a support frame 4, a guide post 5, a linear bearing a6, a blank holder lower plate 7, a ball screw 8, a cavity plate 9, a linear bearing b10, a pull rod 11, a blank holder 12, a blank holder upper plate 13, a male die 14, a guide cylinder 15, a heat insulation plate 16, a female die 17, a screw 18, a screw holder 19, a screw nut 20, a screw holder 21 and a motor 22. The upper blank pressing plate 13 and the lower blank pressing plate 7 are of rectangular structures, pull rods 11 are respectively fastened on the left rear side and the right front side of the upper blank pressing plate 13, guide pillars 5 and linear bearings a6 are respectively fastened on the left side and the right side of the lower blank pressing plate 7, the upper blank pressing plate 13 and the lower blank pressing plate 7 are connected through the pull rods 11, and the pull rods 11 and the guide pillars 5 can respectively slide up and down in the linear bearings b10 and the linear bearings a 6; the female die 17 is preferably arranged to be of a square structure, cylindrical blind holes are formed in the periphery of the female die 17, so that a heating rod can be placed conveniently, and the female die 17 and the heat insulation plate are fixed on the female die plate 9 through screws 18; the male die 14 penetrates through the guide cylinder 15 and the blank holder 12; the blank holder 12 is preferably provided with a square structure and is connected with the heat insulation plate 16 and the blank holder upper plate 13 through four screws; the inner hole in the middle of the blank holder 12 is slightly larger than the diameter of the punch 14, and the diameter of the inner hole of the blank holder 12 is coaxial with the punch 14, so that the blank holder 12 can move up and down relative to the punch 14 without friction; one end of the ball screw 8 is fixed on the support frame 4 through a screw fixing seat 21, and the other end is connected with the concave template 9 through a screw supporting seat 19; the ball screw 8 is connected with the speed reducer 3 in a key connection mode; the motor 22 is connected to the decelerator 3.

In this embodiment, linear bearing b10 and linear bearing a6 are preferably both circular flange series.

In the present embodiment, the ball screw 8 is preferably a 2010-2 series ball screw.

In the present embodiment, the speed reducer 3 is preferably a right-angle speed reducer of a planetary gear structure, and the output end is in the form of a shaft hole.

In the present embodiment, the temperature sensor is preferably a K-type thermocouple.

In this embodiment, the material of the outer layer of the heating rod is preferably stainless steel.

In this embodiment, the motor 22 is preferably a servo motor, an output shaft of the motor 22 is keyed with an input hole of the speed reducer 3, and a flange of the motor 22 is fixed on an input end flange of the speed reducer 3 by a screw.

In this embodiment, the driver panel is preferably a model specification for the motor.

In this embodiment, a thread matched with the temperature sensor is processed in the middle of the side surface of the female die 17.

In this embodiment, the guide pillar 5 is preferably in a stepped form, both ends of the guide pillar are respectively machined with full-thread and half-thread optical axes, the guide pillar 5 passes through a linear bearing a6 installed on the blank-pressing lower plate 7, and the full-thread and half-thread optical axes at both ends of the guide pillar 5 are respectively matched with the positioning holes of the cavity plate 9 and the lower die plate 2 and are fastened at the thread ends through round nuts 1. Correspondingly, the pull rod 11 is preferably in a stepped form, the two ends of the pull rod are respectively processed with full-thread and half-thread optical axes, the pull rod 11 penetrates through a linear bearing b10 arranged on the concave template 9, and the full-thread and half-thread optical axes at the two ends of the pull rod 11 are respectively matched with the positioning holes of the blank-pressing upper plate 13 and the blank-pressing lower plate 7 and are fastened at the thread ends through round nuts 1.

In this embodiment, as shown in fig. 20, which is a schematic diagram of a heating system in a hot-drawing forming device with controllable blank holder force, a heating rod is placed in peripheral blind holes of a blank holder 12 and a female die 17, the female die 17 is connected with a temperature sensor (K-type thermocouple), the heating rod is connected with a solid-state relay, and heating is performed by using an alternating-current voltage; the solid-state relay is connected with a temperature controller, one end of the temperature controller is connected with a temperature sensor (K-type thermocouple), and an RS485 communication interface at the other end is connected with an external PC.

The embodiment also provides a hot-drawing forming method based on the controllable blank holder force of the hot-drawing forming device, and the method comprises the following steps: referring to fig. 1, when a sheet is deep-drawn, firstly, a power supply is switched on, a driver panel drives a motor 22 to rotate, a torque mode in the driver is set by software or manually, blank holding force which can be converted by corresponding torque is estimated through formula back calculation and calibrated through a force sensor, the relation between the motor torque and the blank holding force is determined according to equal interval numerical values, then the sheet to be deep-drawn is placed on a female die 17, the motor 22 drives a reducer 3 to enable a ball screw 8 to rotate, a screw nut 20 on the ball screw 8 moves downwards, a blank holding lower plate 7 (the screw nut 20 is fixed on the blank holding lower plate 7) further drives a pull rod 11, a blank holding upper plate 13 and a blank holding ring 12 to synchronously move downwards, the blank holding ring 12 moves to the upper part of the sheet and stops after a certain gap is left, a switch of a temperature controller is opened, heating temperature is set, so that a heating rod is heated to the set, the temperature sensor is used for monitoring the temperature of the water tank in real time, and constant temperature is maintained. Then, the torque of the motor 22 is set by utilizing the size relation of the blank holding force which can be converted by the torque of the motor and according to the size of the blank holding force required by forming, the motor 22 is started, the blank holding upper plate 13 drives the blank holding ring 12 to move downwards, and the plate is compressed and the pressure in a constant downward direction is kept. The male die 14 moves downwards through the guide cylinder 15 under the control of external test equipment until reaching the corresponding drawing stroke. Then controlling the motor 22 to rotate reversely, enabling the male die 14, the blank holder 12 and the formed part to move upwards for a certain distance along with the blank holder 13, and enabling the formed part to fall down after the male die 14 reaches the surface of the blank holder 12, so that the demolding and unloading processes are completed; at this point, the drawing is completed for one time, and the next drawing is prepared.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the claim concerned.

The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims

1. A hot-drawing forming device capable of controlling blank holder force is characterized by comprising:

2. The controllable blank holder force hot drawing forming device of claim 1, further comprising a blank holder lower plate, wherein the blank holder lower plate is located below the cavity plate and connected with the blank holder upper plate through a pull rod; the displacement adjusting mechanism is connected with the blank pressing lower plate.

3. The blank holder force controllable hot-drawing forming device according to claim 2, wherein a guide post is connected to a lower portion of the cavity plate, and the blank holder lower plate is slidably fitted over the guide post.

4. The hot-drawing forming device with controllable blank holder force of claim 2, wherein the displacement adjusting mechanism comprises a ball screw and a screw nut, one end of the ball screw is connected with a driving motor, the screw nut is connected to the ball screw in a threaded manner, and the screw nut is fixedly connected with the blank holder lower plate.

5. The controlled blank press force hot draw forming apparatus of claim 4, wherein the drive motor is in signal communication with the driver panel.

6. The controlled blank holder force hot draw forming apparatus of claim 1, wherein the punch tip circumscribes a test device.

7. The apparatus of claim 1, wherein the female mold is configured with a force sensor for calibrating the blank force, the force sensor being in signal communication with the actuator panel.

8. A hot-drawing forming method based on a controllable blank holder force of the hot-drawing forming apparatus according to any one of claims 1 to 7, characterized by comprising the steps of:

step five: setting a heating temperature and starting heating;