Background technology
Hot formed processing method is to utilize metal material plasticity at high temperature compared with hypermutation, characteristic that shape drag is less, with powerful pressure and certain speed, force metal blank to produce Plastic Flow, by the gap of punch and die or the outlet of die, extrude solid member hollow or that section is less than blank section.Adopt the part of heat forming technology processing to have that metal streamline is continuous, intensity is high, plasticity is strong, and formed precision is high, the features such as in moulding stroke, frictional force is little, and heat is transmitted more even, and mechanical property is extremely strong, process security is higher, has better economic benefit and social benefit.
Since resistance of deformation when nineteen fifty-five F.Blaha and B.Langenecker have disclosed first additional Under Ultrasonic Vibration kinetic energy and reduce the plastic deformation of monocrystal zinc, many scholars of countries in the world for vibration the application start in Metal Forming theoretical and experimental study extensively and profoundly.After adopting hydraulic pressure dither to combine with metal fever forming technique, material while being conducive to part forming flows, and can improve the Frotteurism between metal and mould, reduces the frictional force of blank and die surface, reduce internal stress, thereby reach the feature that reduces extruding force.Because amplitude is small, also can not affect the dimensional accuracy of drip molding.At present, be applied in the drawing of wire rod, tubing and heterotypic material, in the process such as the punching of metal material, shearing, pressure-sizing, rolling, the exciting mode adopting mainly be take power ultrasonic vibration and mechanical type as main, both have very significantly limitation, such as direction of vibration is limited, power output is limited, generation exciting force is less, and frequency and amplitude are difficult to regulate.
Summary of the invention
The multidirectional dither hot-forming die of multimode that resistance is low, load stable, extruding force is relatively little that while the object of this invention is to provide a kind of hot forming workpiece, the flow stress of metal material is little, metal flows into die.
The object of the present invention is achieved like this:
The multidirectional dither hot-forming die of multimode, comprises patrix, patrix and is the guide post of upper and lower mould relative motion guiding, the downside of described counterdie is provided with and can carries out to multiple directions the hydraulic vibration exciter of dither.
The concrete structure of above-mentioned hydraulic vibration exciter is: in hydraulic vibration exciter outer ring, be provided with excitor, on at least one horizontal plane of excitor and at least one vertical plane, be respectively arranged with more than one groove, the opening part of each groove is provided with flexible end cap and forms flutter chamber, all flutter chambeies are all communicated with the exciting valve of driven by servomotor by conduit under fluid pressure, and the oil-in of exciting valve is communicated with by conduit with the high pressure oil-out of hydraulic press.
On the pipeline that above-mentioned flutter chamber is communicated with exciting valve, be provided with the speed change cavity of variable volume.
In above-mentioned speed change cavity, be provided with piston speed change cavity is divided into frequency conversion chamber and connecting rod chamber, in connecting rod chamber, be provided with the connecting rod outside connecting rod chamber that stretches out being connected with piston, the volume size in the diverse location by connecting rod capable of regulating piston in speed change cavity and then adjustment frequency conversion chamber, realizes the change of vibration frequency.
The maximum speed of above-mentioned servomotor is 3000 turn/min, the spool both sides of described exciting valve have the window that eight equal and opposite in direction angles are staggered, between servomotor and spool, be connected with the gearbox of a 1:2, therefore theoretical highest frequency is 50 * 2 * 16=1500Hz.
There are flutter chamber on horizontal plane and the flutter chamber on vertical plane in above-mentioned flutter chamber, and the volume ratio in the volume in the flutter chamber on vertical plane and the flutter chamber on horizontal plane is 1:2.
The concrete structure of above-mentioned patrix is: punch pad, on punch cushion block, is fixed on punch on cope match-plate pattern with bolt together with punch cushion block and punch trim ring; The concrete structure of described counterdie is: by die trim ring and die, by the bodily form, agreed with, by bolt, be fixed on hydraulic vibration exciter outer ring together with die cushion block, and be finally bolted on lower bolster.
Above-mentioned hydraulic vibration exciter is arranged between counterdie and lower bolster.
Above-mentioned hydraulic vibration exciter shares a high-pressure oil pump for its voltage supply with the forcing press that drives patrix to move up and down.
The present invention compared to existing technology outstanding and useful technique effect is:
The present invention adopts hydraulic vibration technology, there is the large feature of output exciting force, can realize the multidirectional vibration of mould in hot extrusion process, also can realize the stepless adjustment of frequency and amplitude, thereby well overcome the limitation of traditional ultrasonic vibration and mechanical type vibration, under flutter fashion of extrusion, high frequency flutter due to die, during hot forming workpiece, reduced the flow stress of material, and improved the Frotteurism between blank and die, the resistance that metal flows into die reduces, thereby make load remain on a metastable level, for thermoforming processing, not only can reduce the size of extruding force, and Technology for Heating Processing is also had to very significantly effect, there is important theory significance and Practical background.
The specific embodiment
Below in conjunction with accompanying drawing, with specific embodiment, the invention will be further described, referring to Fig. 1-Fig. 7:
The multidirectional dither hot-forming die of multimode, comprises patrix A, patrix A and is the guide post 11 of upper and lower mould relative motion guiding, the downside of described counterdie B is provided with and can carries out to multiple directions the hydraulic vibration exciter 10 of dither.
The concrete structure of above-mentioned hydraulic vibration exciter 10 is: in the 10b of hydraulic vibration exciter outer ring, be provided with excitor 10a, on at least one horizontal plane of excitor 10a and at least one vertical plane, be respectively arranged with more than one groove, the opening part of each groove is provided with flexible end cap 101,105 and forms flutter chamber 102,104, all flutter chambeies 102,104 are all communicated with the exciting valve 14 that servomotor 13 drives by conduit under fluid pressure 103, and the oil-in of exciting valve 14 is communicated with by conduit with the high pressure oil-out of hydraulic press.
On the pipeline that above-mentioned flutter chamber 102,104 is communicated with exciting valve 14, be provided with the speed change cavity of variable volume.
In above-mentioned speed change cavity, be provided with piston 108 speed change cavity is divided into frequency conversion chamber 109 and connecting rod chamber 106, in connecting rod chamber 106, be provided with the connecting rod 107 outside connecting rod chamber 106 that stretches out being connected with piston 108, the volume size in the diverse location by connecting rod 107 capable of regulating pistons 108 in speed change cavity and then adjustment frequency conversion chamber 109, realizes the change of vibration frequency.
The maximum speed of above-mentioned servomotor 13 is 3000 turn/min, spool 141 both sides of described exciting valve 14 have the window that eight equal and opposite in direction angles are staggered, between servomotor 13 and spool 14, be connected with the gearbox of a 1:2, therefore theoretical highest frequency is 50 * 2 * 16=1500Hz.
There are flutter chamber 104 on horizontal plane and the flutter chamber 102 on vertical plane in above-mentioned flutter chamber, and the volume ratio in the volume in the flutter chamber 102 on vertical plane and the flutter chamber 104 on horizontal plane is 1:2.
The concrete structure of above-mentioned patrix A is: punch 4 pads, on punch cushion block 2, are fixed on punch 4 on cope match-plate pattern 1 with bolt together with punch cushion block 2 and punch trim ring 3; The concrete structure of described counterdie B is: by die trim ring 5 and die 6, by the bodily form, agreed with, be fixed on hydraulic vibration exciter outer ring 9, and be finally bolted on lower bolster 12 by bolt together with die cushion block 8.
Above-mentioned hydraulic vibration exciter 10 is arranged between counterdie and lower bolster 12.
Above-mentioned hydraulic vibration exciter 10 shares a high-pressure oil pump 16 for its voltage supply with the forcing press 19 that drives patrix A to move up and down.
During work, hydraulic vibration exciter 10 shares a high-pressure oil pump 16 for its voltage supply with the forcing press 19 that drives patrix A to move up and down, and when forcing press 19 starts to push work, the exciting oil circuit 13 of hydraulic vibration exciter 10 is also opened simultaneously.High frequency by exciting valve 14 rotates, thereby changes the high frequency switching of flutter chamber 102,104 interior high-low pressure oil pressure, thereby produces high frequency flutter.Therefore in bearing of die extrusion sections, hydraulic vibration exciter 10 is also worked, and drives die synchronous vibration with certain frequency and amplitude.The material when flutter of high frequency is conducive to part forming flows, and can improve friction condition and reduce flow stress, thereby reaches the object of antifriction load shedding.In addition,, because the amplitude of flutter is small, can not affect the dimension precision requirement of drip molding.
Fig. 2 forms the fundamental diagram of the interior high-low pressure oil pressure switching in flutter chamber 102,104 of hydraulic vibration exciter 10 together with Fig. 3.The rotation of exciting valve 14 is driven by servomotor 13, the valve port area size that eight grooves that make circumferentially evenly to offer along spool land match with window on valve pocket becomes cyclically-varying, and the groove mutual dislocation on adjacent shoulder, forms by the periodically-varied of the fluid direction of exciting valve 14.During work, when spool 141 goes to position shown in Fig. 2, P-A is communicated with, hydraulic oil by exciting valve 14 from oil pump 16(or claim oil sources) enter flutter chamber 102,104, make two elasticity end caps 101,105 to diagram upside and left side, be out of shape and heave respectively; When spool 141 goes to Fig. 3 position, the notch of right side shoulder and valve pocket window are linked up, A-T is communicated with, hydraulic oil in flutter chamber 102,104 flows back to fuel tank by exciting valve 14, and origin-location is arrived in 101,105 deformation-recoveries of elasticity end cap, thereby realizes the process of high frequency flutter.Utilize the fluid uninterrupted in the adjustable turnover flutter of plug-in mounting choke valve chamber, and then realize the adjusting of flutter device disresonance point amplitude.
In addition between exciting valve 14 and servomotor 13, can embed gearbox, thereby produce higher excited frequency.Flutter chamber is modularization also, as shown in Figure 4.A plurality of vibration module 151,152,153,154 structures are identical, are used for producing exciting force.It is connected with exciting valve 156 by contiguous block 155, then by the turnover of exciting valve 156 regulator solution force feeds, and then the frequency and the amplitude that regulate vibration module 151,152,153,154 to vibrate are realized synchronous vibration.Thereby realize and need to select module number for different.
The hydraulic circuit of the hydraulic vibration exciter 10 of designed mould is the part in the hydraulic system of forcing press 19, shares an oil sources with forcing press 19.When punch 4 starts to push workpiece 7, system pressure raises through high-pressure oil pump 16, when pressure reaches the set pressure of overflow valve 18, now overflow valve 18 is opened, fluid enters in exciting loop, control signal makes servomotor 13 must establish the rotation of beginning by cable, under the control of exciting valve 10, and the vibration that makes flutter chamber 102,104 produce high frequencies.
System relevant parameter and experimental study are as follows:
Under Deform simulation analysis, the hot-forming die system relevant parameter of setting is as shown in table 1
table 1 hot forming tool relevant parameter table:
Because the maximum speed of motor is 3000 turn/min, spool both sides have the window that 8 equal and opposite in direction angles are staggered, and embed the gearbox of a 1:2 between motor and spool, and therefore theoretical highest frequency is 50 * 2 * 16=1500Hz.The volume ratio in the volume in the flutter chamber 102 on vertical plane and the flutter chamber 104 on horizontal plane is 1:2, so the amplitude of side-to-side vibrations is up-down vibration 1/2.Hydraulic vibration exciter relevant parameter is as shown in table 2
Table 2 hydraulic vibration exciter relevant parameter table:
Fig. 6 and Fig. 7 are respectively traditional thermoforming processing and load high-frequency excitation frequency is that 1000Hz left and right amplitude is 0.005mm, the stroke load diagram of thermoforming processing when upper and lower amplitude is 0.01mm, and the load change trend of two curves is basically identical generally.In the end of a period stage being shaped, under traditional hot extrusion mode, the frictional force being subject to while entering die inner chamber due to blank constantly increases, metal flow difficulty, so loading force rises very fast.And under flutter fashion of extrusion, due to the high frequency flutter of die, reduced the flow stress of material, and improved the Frotteurism between blank and die, the resistance that metal flows into die reduces, thereby makes load remain on a metastable level.As can be seen from the figure, under conventional extruded mode, maximum load is about 244Mpa, and under flutter fashion of extrusion, final load is about 210Mpa, has reduced by 14%, and effect is remarkable.
Above-described embodiment is only preferred embodiment of the present invention, not limits the scope of the invention according to this, therefore: all equivalences of doing according to structure of the present invention, shape, principle change, within all should being covered by protection scope of the present invention.