CN107120374A - A kind of automobile-used torsion-bar spring and its manufacture method - Google Patents
A kind of automobile-used torsion-bar spring and its manufacture method Download PDFInfo
- Publication number
- CN107120374A CN107120374A CN201710177191.2A CN201710177191A CN107120374A CN 107120374 A CN107120374 A CN 107120374A CN 201710177191 A CN201710177191 A CN 201710177191A CN 107120374 A CN107120374 A CN 107120374A
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- China
- Prior art keywords
- torsion
- bar spring
- pretwist
- bar
- automobile
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F1/00—Springs
- F16F1/02—Springs made of steel or other material having low internal friction; Wound, torsion, leaf, cup, ring or the like springs, the material of the spring not being relevant
- F16F1/14—Torsion springs consisting of bars or tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/02—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for springs
Abstract
The invention discloses a kind of automobile-used torsion-bar spring and its manufacture method, the torsion-bar spring is divided into end, bar portion and the part of changeover portion three.Its changeover portion is not to use quarter circular arc transition, but uses hyperbolic shape, to obtain smoother surface stress.Its manufacture method, forged including blanking, end upsetting, once cold extrusion pressure, secondary cold extrusion, heat treatment, hot pretwist, normal temperature pretwist, segmentation shot-peening, examine antirust, the torsion-bar spring manufactured using above-mentioned process, can effectively improve production efficiency, improve the fatigue life of end surface quality and torsion-bar spring.
Description
Technical field
The present invention relates to a kind of automobile-used torsion-bar spring and its manufacture method, belong to technical field of automobile accessories.
Background technology
Compared with helical spring and leaf spring, torsion-bar spring is simple in construction, without friction during work, spring performance is stable, does not produce
Raw flutter, unit volume energy storage is big, and spring small volume belongs to miniaturization product, in automobile, train, tank and plate armour
Extensive use is obtained in terms of car.There are circle, side, rectangle, ellipse and polygon etc. in torsion-bar spring section, and using section as circle
Shape is in the majority.Domestic torsion-bar spring at present uses high-carbon alloy steel or medium carbon steel steel alloy mostly（As 60CrA, 60Si2Mn,
42CrMo, 50CrVA etc.）Production.Conventional fabrication processes, sequentially include blanking, end upsetting, soft annealing, cold extrusion, heat
Processing, normal temperature pretwist（Repeatedly）, shot-peening（Full spray or half spray）, examine antirust, wherein soft annealing needs the time longer, and normal temperature is pre-
Torsion, which is generally required, to be turned round 5-6 times by force, in addition, during shot-peening, being sprayed if only implementing half, i.e. bar portion shot-peening, end spline is not sprayed,
Then there is surface stress mutation in shot-peening area with non-shot-peening area, if implementing full spray, i.e. bar portion and the whole shot-peenings of end spline, then spend
Key end surfaces quality can decline.In addition, circular arc common in torsion-bar spring changeover portion or the processing method of straight line taper transitions are simultaneously
It is not inconsistent the requirement of combined stress smooth uniform.Therefore, traditional torsion-bar spring Research on Manufacturing Method need to be optimized, to solve to manufacture
Defect in journey, improves manufacture efficiency, so as to further improve the fatigue life of torsion-bar spring.
The content of the invention
The present invention provides a kind of automobile-used torsion-bar spring and its manufacture method in order to solve the defect of above-mentioned prior art.
The purpose of the present invention is realized by following technical solution：
A kind of automobile-used torsion-bar spring, is prepared by medium carbon alloy steel, including end, bar portion, the part of changeover portion three.Wherein changeover portion is not
It is simple using quarter circular arc or straight line taper transitions, but uses the transition of hyperbolic shape, its transition section length L2=
（2~2.5）R2, to reach stress variation at utmost uniform smooth.
The invention also discloses the manufacture method of the automobile-used torsion-bar spring, comprise the following steps：
（1）Blanking, carbon alloy pole during raw material is used, the polished rod of size needed for machine is cut into；
（2）End upsetting, 1200~1300 DEG C are heated to by ends of torsion bar spring, and upsetting is carried out on warm forming machine, are added with being formed
The hardness number of blank is examined in blank cylinder needed for work spline, upsetting after terminating；
（3）Once cold extrusion pressure, due to eliminating soft annealing process, blank hardness reaches more than 300HB, therefore carries out cold twice
Extrusion molding spline, once cold extrusion needs to be made as spline forming height H1 into the 60%~80% of final forming height H2 when pressing.
（4）Secondary cold extrusion, changes cutter, by blank centering, carries out secondary cold extrusion, completes residue 20%~40% and adds
The extrusion process of work amount.
（5）Heat treatment, torsion-bar spring blank integrally carries out mid-frequency induction hardening, and hardening heat is 850~900 DEG C, temperature
Fluctuation range ± 15 DEG C, soaking time is torsion-bar spring length L1（Unit：mm）' 1 minute, soaking time fluctuation range ± 2 point
Clock.Using the protection gas that high-purity nitrogen is made to quench is filled, to reduce torsion-bar spring outer surface decarburization after the depth of decarburized layer, quenching
Depth is no more than 0.01mm ' F (units：mm).After quenching, high tempering is carried out, to eliminate the internal stress that quenching triggers, is returned
Fiery temperature control is at 600~650 DEG C.
（6）Torsion-bar spring, is put into torsion testing machine with mechanical hand or automatic conveying device and carries out hot pretwist by hot pretwist, heat
Torsion-bar spring surface temperature control during torsion is at 300~320 DEG C；Such as torsion-bar spring maximum functional windup-degree is a, then heat is pre-
Turning round angular interval is（a+8o, a+10 o）, torsional angle allowance control is ± 1 o。
（7）1~2 normal temperature pretwist is carried out after normal temperature pretwist, hot pretwist again, windup-degree is less than hot Pretwist angle, but will
More than maximum functional windup-degree a, normal temperature Pretwist angle interval is（a+2o, a+8o）, such as using normal temperature pretwist twice, then second
Secondary Pretwist angle is less than first time Pretwist angle 2o, each pretwist torsional angle allowance control is ± 1o, last time normal temperature pretwist,
Answer≤0.1 in the residual deformation angle of torsion-bar springo。
（8）Shot-peening is segmented, shot peening strengthening is the important procedure for improving torsion-bar spring fatigue strength.Torsion-bar spring is after shot-peening
Surface produces plastic deformation, is formed in certain thickness surface peening layer, strengthening layer and forms higher residual compressive stress and density
High dislocation, that is, top layer flow harden, thus improve the fatigue life of torsion-bar spring.The present invention is using segmentation shot-peening
Mode carry out, end spline sprays thin shot, and thin shot diameter d1 is the 1/3~1/4 of spline serration radius of corner R1, bar portion and
Changeover portion uses crude steel ball, and crude steel ball diameter d2 is the 2%~4% of gauge diameter F.
（9）Examine and antirust, carry out nondestructive inspection, check surface and the internal soundness of torsion-bar spring, meanwhile, check surface
Precision and dimensional tolerance, qualified rear progress antirust treatment.
It is by above-mentioned technical proposal beneficial effects of the present invention：
1st, compared with traditional torsion-bar spring manufacture method, the technology of the present invention adds secondary cold-extrusion technology, and eliminates annealing
Softening process, because the once cold extrusion pressure time is well below annealing software time, so, save the production time.Meanwhile, it is high hard
Degree（≥300HB）Under the conditions of cold-extrusion technology, improve the case hardness of splined end, be conducive to improving the splined end tired longevity
Life.
2nd, compared with traditional torsion-bar spring manufacture method, the technology of the present invention adds once hot pretwist technique, makes normal temperature pre-
Turn round number of times to be reduced to 1-2 times by 5-6 times, further reduce the production time.Meanwhile, hot pretwist can improve metal metallographic group
Knit, reduce torsion-bar spring relaxation deflection.
3rd, the present invention is using the technique for being segmented shot-peening, and bar portion uses crude steel ball, and end spline end uses thin shot, both formed
Certain thickness cementation zone, has reached the purpose for the fatigue life for improving torsion bar.Simultaneously, it is to avoid classical production process
What the surface quality for the splined end that the not enough and full pressure spray process for the stress mutation that half pressure spray process used is brought is brought declined lacks
Fall into.
4th, compared with traditional torsion-bar spring changeover portion is using quarter circular arc or the structure of straight line taper transitions, the present invention
The changeover portion of torsion-bar spring can obtain more smooth surface stress using the transition of the hyperbolic shape of class tree root shape.
Brief description of the drawings
Fig. 1 is the structural representation of automobile-used torsion-bar spring of the invention；
Fig. 2 is the changeover portion enlarged drawing of Fig. 1 torsion-bar spring；
Fig. 3 is that the once cold extrusion pressure of the present invention and the shape of secondary cold extrusion are illustrated；
In figure：1- splined ends, 2- changeover portions, 3- bar portions.
Embodiment
Below in conjunction with the accompanying drawings come illustrate the present invention embodiment.Obviously, the embodiment of description is the one of the present invention
Section Example, rather than whole embodiments.Based on embodiments of the invention, one of ordinary skill in the art is not making
The all other embodiment obtained on the premise of creative work, belongs to the scope of protection of the invention.
Embodiment 1
As Figure 1-3, a kind of automobile-used torsion-bar spring, is made up of, its overall length splined end 1, changeover portion 2, the part of bar portion 3 three
Spend L1, gauge diameter F=27mm, hyperbola transition section length L2, spline serration root fillet radius R1, traditional quadrant
The radius of arc transition is R2, the R2 of L2=2 '.
A kind of automobile-used torsion-bar spring manufacture method, raw material metal selects medium carbon alloy steel 42CrMo, comprises the following steps：
（1）Blanking, the polished rod of size needed for machine is cut into, its length should be greater than L1；
（2）End upsetting, 1200 DEG C are heated to by ends of torsion bar spring, are carried out on warm forming machine needed for upsetting is processed into spline
Blank cylinder, after upsetting terminates, examine blank hardness number whether≤300HB；
（3）Once cold extrusion pressure, due to eliminating soft annealing process, therefore carries out cold-extrusion shaping spline, once cold extrusion pressure twice
When need to be processed as spline forming height H1 into the 60% of final forming height H2.
（4）Secondary cold extrusion, changes cutter, by blank centering, carries out secondary cold extrusion, completes the extruding of residue 40%
Processing.
（5）Heat treatment, spring blank of wringing dry integrally carries out mid-frequency induction hardening, and hardening heat is 850 DEG C, temperature fluctuation model
± 15 DEG C are enclosed, soaking time is torsion-bar spring length L1 ' 1 minute, soaking time fluctuation range ± 2 minute.Using filling high-purity
Nitrogen makees the protection gas that quenches, to reduce after the depth of decarburized layer, quenching torsion-bar spring outer surface decarburized depth no more than
0.27mm.After quenching, high tempering is carried out, to eliminate the internal stress that quenching triggers, temperature is controlled at 600 DEG C.
（6）Torsion-bar spring, is put into torsion testing machine with mechanical hand or automatic conveying device and carries out hot pretwist by hot pretwist, heat
Torsion-bar spring surface temperature control during torsion is at 300 DEG C；Such as torsion-bar spring maximum functional windup-degree is a, then hot pre- torsional angle
Spend for a+8o, torsional angle allowance control is ± 1o。
（7）1 normal temperature pretwist is carried out after normal temperature pretwist, hot pretwist again, normal temperature Pretwist angle is a+2o, torsional angle allowance control
± 1o, after normal temperature pretwist, the residual deformation angle of torsion-bar spring should≤0.1o。
（8）Shot-peening is segmented, is carried out by the way of segmentation shot-peening, end spline sprays thin shot, thin shot diameter d1 is flower
The 1/4 of key serration radius of corner R1, bar portion uses crude steel ball, crude steel ball diameter d2=0.54mm.
（9）Examine and antirust, carry out nondestructive inspection, check surface and the internal soundness of torsion-bar spring, meanwhile, check surface
Precision and dimensional tolerance, qualified rear progress antirust treatment.
Embodiment 2
Using manufacture method same as Example 1, its difference is, raw material metal selects medium carbon alloy steel 50CrVA, F
The R2 of=27mm, L2=2.5 ', wherein, during the upsetting of end, ends of torsion bar spring is heated to 1300 DEG C, H1=80%H2；In heat treatment
Frequency impewdance matching temperature is 900 DEG C, 650 DEG C of temperature；Torsion-bar spring surface temperature control is 320 DEG C during hot pretwist, and heat is pre-
Torsional angle degree is a+10 o；Normal temperature pretwist twice is carried out, first time Pretwist angle is a+8o, second of Pretwist angle is a+6o；d1=
1/3R1, d2=1.08mm.
Claims (4)
1. a kind of automobile-used torsion-bar spring, is divided into end, bar portion and changeover portion, it is characterised in that：In the middle of end and bar portion
Changeover portion use hyperbolic shape transition, its transition length L2 for existing quarter circular arc transition arc radius R2 2~
2.5 again.
2. the manufacture method of the automobile-used torsion-bar spring described in a kind of claim 1, it is characterised in that comprise the following steps：
（1）Blanking, raw material uses medium carbon alloy steel pole, and machine cuts into the polished rod of required size；
（2）End upsetting, 1200~1300 DEG C are heated to by ends of torsion bar spring, and upsetting is carried out on warm forming machine, are added with being formed
The hardness number of blank is examined in cylinder blank needed for work end spline, upsetting after terminating；
（3）Once cold extrusion pressure, the 60%~80% of final forming height H2 is processed as by spline forming height H1；
（4）Secondary cold extrusion, changes cutter, by blank centering, carries out secondary cold extrusion, completes remaining 20%~40% processing capacity
Extrusion process；
（5）Heat treatment, mid-frequency induction hardening is integrally carried out by torsion-bar spring blank, and hardening heat is 850~900 DEG C, temperature wave
Dynamic scope ± 15 DEG C, soaking time is torsion-bar spring mm length L1 ' 1 minute, soaking time fluctuation range ± 2 minute；Using
Fill high-purity nitrogen and make the protection gas that quenches, to reduce after the depth of decarburized layer, quenching torsion-bar spring outer surface decarburized depth not
It can exceed that 0.01mm ' bar portion mm dias F；After quenching, high tempering is carried out, to eliminate the internal stress that quenching triggers, tempering
Temperature control is at 600~650 DEG C；
（6）Torsion-bar spring, is put into torsion testing machine with mechanical hand or automatic conveying device and carries out hot pretwist, Heat torsion by hot pretwist
When torsion-bar spring surface temperature control at 300~320 DEG C；Such as torsion-bar spring maximum functional windup-degree is a, then hot pre- torsional angle
Degree interval is（a+8 o, a+10o）, torsional angle allowance control is ± 1 o；
（7）1~2 normal temperature pretwist is carried out after normal temperature pretwist, hot pretwist again, windup-degree is less than hot Pretwist angle, more than maximum
Working torsional angle degree a, such as using normal temperature pretwist twice, then second of Pretwist angle is less than first time Pretwist angle 2o, every time
Pretwist torsional angle allowance control is ± 1o, last time normal temperature pretwist, the residual deformation angle of torsion-bar spring answers≤0.1o；
（8）Shot-peening is segmented, end spline sprays thin shot, and thin shot diameter d1 is the 1/3~1/4 of spline serration radius of corner R1,
Bar portion and changeover portion use crude steel ball, and crude steel ball diameter d2 is the 2%~4% of gauge diameter F；
（9）Examine and antirust, carry out nondestructive inspection, check surface and the internal soundness of torsion-bar spring, meanwhile, check surface accuracy
And dimensional tolerance, qualified rear progress antirust treatment.
3. a kind of manufacture method of automobile-used torsion-bar spring according to claim 2, it is characterised in that：The step（1）In
Torsion-bar spring material use medium carbon alloy steel, including 42CrMo, 50CrVA.
4. a kind of manufacture method of automobile-used torsion-bar spring according to claim 2, it is characterised in that：The step（7）In
Normal temperature Pretwist angle interval be（a+2o, a+8o）.
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| CN201710177191.2A CN107120374B (en) | 2017-03-23 | 2017-03-23 | A kind of automobile-used torsion-bar spring and its manufacturing method |
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| CN201710177191.2A CN107120374B (en) | 2017-03-23 | 2017-03-23 | A kind of automobile-used torsion-bar spring and its manufacturing method |
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| CN107120374B CN107120374B (en) | 2019-02-15 |
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Cited By (3)
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| CN108942096A (en) * | 2018-07-17 | 2018-12-07 | 齐齐哈尔北盛机械制造有限公司 | Torsion bar shaft processing method |
| CN114248064A (en) * | 2020-09-21 | 2022-03-29 | 航天科工哈尔滨风华有限公司 | Manufacturing method of high-stability strong torsion bar spring |
| CN115464347A (en) * | 2022-10-19 | 2022-12-13 | 江苏三众弹性技术股份有限公司 | Spring hot cutting forming production process and disc spring |
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| CN115464347A (en) * | 2022-10-19 | 2022-12-13 | 江苏三众弹性技术股份有限公司 | Spring hot cutting forming production process and disc spring |
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| CN107120374B (en) | 2019-02-15 |
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