CN102305258B - Sleeve coil spring for damper and manufacturing method thereof - Google Patents

Abstract

The invention belongs to the field of coil spring manufacturing, and provides a method for manufacturing a shock absorber sleeve coil spring, which includes the following steps: performing material detection and analysis on the imported sleeve coil spring, selecting raw materials for developing the coil spring, and according to Analyze the structure of the sleeve coil spring, determine the shape and size of the blank, use the bending die to bend and roll the blank, and heat-treat the obtained reed, and use the assembly mold to assemble the reed into a sleeve coil spring. The invention adopts the reed bending mold with high dimensional accuracy and good surface quality to bend the reed to ensure the concentricity and curvature of the unequal thickness coil spring, and uses the extrusion assembly mold to complete the assembly of the reed, ensuring The rationality of the assembly gap between each reed ensures the accuracy of coil spring assembly, fills a gap in the diesel engine industry in my country, enhances the domestic ability to research and develop high-performance diesel engine shock absorber coil springs, and improves The level of production and preparation of shock absorber sleeve coil springs.

Description

A method of manufacturing a shock absorber sleeve coil spring

technical field

The invention belongs to the field of coil spring manufacturing, in particular to a method for manufacturing a shock absorber sleeve coil spring.

Background technique

Throughout the development of diesel engines, there are almost no high-power diesel engines that do not use vibration reduction technology. There are many structures of shock absorbers. At present, there are mainly damping type, power type and hybrid type. The characteristic of the damping type is to use damping to eliminate the excitation energy to achieve the purpose of vibration reduction, such as silicone oil shock absorber; the dynamic type is to use the dynamic effect of resonance to generate a counter torque change system that is equal in magnitude and opposite in direction to the disturbance torque. Vibration form to achieve the purpose of vibration reduction, such as pendulum type shock absorber; hybrid shock absorber has the characteristics of the above two kinds of shock absorbers, not only has the damping effect of vibration reduction, but also has a large flexibility, relying on changing Vibration reduction by mode shape represents the development direction of shock absorbers, such as diesel engine shock absorbers.

The high-power marine diesel engine imported from Germany is famous for its high reliability and strong power. The sleeve coil spring shock absorber is a patented product of a German company. There is still no domestic product that can replace the shock absorber. Although there are many studies on diesel engine shock absorbers in my country, the elastic element generally studied is springs rather than coil springs. , while coil springs are strictly kept secret due to foreign related manufacturing technology and alloy composition (mainly referring to trace elements), and the lack of related preparation technology, especially the lack of heat treatment forming technology for corresponding materials, the development results of high-performance coil spring products are not ideal , At present, the method of purchasing from abroad is still used to meet the production of diesel engines. Therefore, it is necessary to carry out the research and development of the localization of the shock absorber sleeve coil spring.

Contents of the invention

The invention provides a method for manufacturing coil springs of shock absorber sleeves, aiming to solve the problem that the current domestic production technology of coil springs is relatively backward and lacks heat treatment forming technology for corresponding materials. The research and development results of high-performance coil spring products are not satisfactory, and the method of purchasing shock absorbers from abroad is used to meet the problem of diesel engine production.

The object of the present invention is to provide a kind of manufacturing method of shock absorber sleeve coil spring, this method comprises the following steps:

Carry out material detection and analysis on the original parts of imported sleeve coil springs, and select the raw materials for the development of coil springs;

According to the analysis of the structure of the sleeve coil spring, determine the shape and size of the blank;

Use a bending die to bend and roll the billet, and heat-treat the obtained reeds one by one;

Use the assembly mold to assemble the reed into a sleeve coil spring.

Another object of the present invention is to provide a shock absorber sleeve coil spring, the coil spring includes: a first reed, a second reed, a third reed, a fourth reed, a fifth reed, a sixth reed Reed, seventh reed, eighth reed;

The first reed is installed on the innermost layer of the coil spring, the second reed is installed outside the first reed, and the third reed is installed outside the second reed, so The fourth reed is installed outside the third reed, the fifth reed is installed outside the fourth reed, the sixth reed is installed outside the fifth reed, and the fifth reed is installed outside the fifth reed. The seventh reed is installed outside the sixth reed, and the eighth reed is installed outside the seventh reed;

The bending mold includes: a top block, an upper mold, a rolling hole, and a lower mold;

The top block is installed on the upper die, and the rolling holes are arranged on the tops of the upper die and the lower die.

The present invention bends a single reed by adopting a reed bending die with high dimensional accuracy and good surface quality, which ensures the concentricity and curvature of multiple unequal-thickness coil springs, and uses extrusion assembly dies to complete the bending process of the reed. The assembly ensures the rationality of the assembly gap between the reeds, ensures the accuracy of the coil spring assembly, fills a gap in the diesel engine industry in my country, and strengthens the domestic research and development of high-performance diesel engine shock absorber coil springs. The capacity has improved the production and preparation level of shock absorber sleeve coil spring.

Description of drawings

Fig. 1 is the flowchart of the shock absorber sleeve coil spring provided by the embodiment of the present invention;

2 is a schematic structural view of a shock absorber sleeve coil spring provided by an embodiment of the present invention;

Fig. 3 is a schematic structural view of a reed bending die provided by an embodiment of the present invention;

Fig. 4 is a schematic diagram of the results of the mechanical performance test and analysis of the reed and the coil spring provided by the embodiment of the present invention.

In the figure: 1, coil spring; 11, the first reed; 12, the second reed; 13, the third reed; 14, the fourth reed; 15, the fifth reed; 16, the sixth reed; 17. The seventh reed; 18. The eighth reed; 2. The top block; 3. The upper die; 4. The rolling hole; 5. The lower die.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the invention.

Fig. 1 shows the implementation process of the shock absorber sleeve coil spring provided by the embodiment of the present invention.

A method of manufacturing a shock absorber sleeve coil spring, the method comprising the following steps:

In step S101, the raw material of the imported sleeve coil spring is tested and analyzed, and the raw material for developing the coil spring 1 is selected;

In step S102, according to the analysis of the structure of the sleeve coil spring, the shape and size of the blank are determined;

In step S103, the billet is bent and rounded by using a bending die, and the obtained reeds are heat-treated one by one;

In step S104, the reed is assembled into a sleeve coil spring by using an extrusion assembly mold.

In the embodiment of the present invention, the material detection and analysis of the imported sleeve coil spring is carried out, and the realization method of selecting the raw material for developing the coil spring is as follows:

Under the detection conditions of room temperature of 25°C and humidity of 48%, a full-spectrum DC ICP spectrometer and an infrared carbon-sulfur analyzer were used to conduct material testing and analysis on the imported sleeve coil spring 1, and the sleeve coil spring was initially selected for development. raw materials;

Measure the decarburization depth of the selected raw material to make it meet the requirements of spring materials with different materials and different diameters specified in GB1222-84;

Measure and control the content of non-metallic inclusions in the selected materials, so that non-metallic inclusions shall not exceed grade 2.5, and the average diameter of other impurities shall be below 10 μm;

Select the raw materials that meet the above requirements as the object of development, or re-select the raw materials and conduct measurements to make them meet the above requirements for raw materials.

Fig. 2 shows the structure of the shock absorber sleeve coil spring provided by the embodiment of the present invention. For ease of illustration, only the parts relevant to the present invention are shown.

The coil spring 1 includes: a first reed 11, a second reed 12, a third reed 13, a fourth reed 14, a fifth reed 15, a sixth reed 16, a seventh reed 17, an eighth reed reed 18;

The first reed 11 is installed on the innermost layer of the coil spring 1, the second reed 12 is installed on the outside of the first reed 11, the third reed 13 is installed on the outside of the second reed 12, and the fourth reed 14 is installed on the outside of the first reed 11. Outside the third reed 13, the fifth reed 15 is installed outside the fourth reed 14, the sixth reed 16 is installed outside the fifth reed 15, the seventh reed 17 is installed outside the sixth reed 16, and the sixth reed 16 is installed outside the sixth reed 16. Eight reeds 18 are installed outside the seventh reed 17 .

As a preferred solution of the embodiment of the present invention, each reed is provided with openings of different widths.

As a preferred solution of the embodiment of the present invention, the shape of each reed is designed as a circle with an opening.

Fig. 3 shows the structure of the reed bending mold provided by the embodiment of the present invention. For ease of illustration, only the parts relevant to the present invention are shown.

The bending mold includes: a top block 2, an upper mold 3, a rolling hole 4, and a lower mold 5;

The ejector block 2 is installed on the upper die 3, and the rolling hole 4 is arranged on the tops of the upper die 3 and the lower die 5.

As a preferred solution of the embodiment of the present invention, the top of the top block 2 is an arc tangent to the rolling hole 4 .

As a preferred solution of the embodiment of the present invention, the upper mold 3 is provided with holes for installing the top block 2 .

The application principle of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

1. Raw material inspection

(1) Composition analysis of imported coil spring 1

We used a full-spectrum DC ICP spectrometer and an infrared carbon-sulfur analyzer to conduct material testing and analysis on imported parts (the testing environment conditions were room temperature 25°C, humidity 48%), and found that its chemical composition is as follows: Table 1:

Table 1 Chemical Composition of Imported Coil Spring 1

element C Si mn S P Cr V content 0.51 0.25 0.57 0.012 0.016 0.88 0.16

Through testing, we found that its chemical composition is very close to the domestic 50CrVA, and the chemical composition of 50CrVA is shown in Table 2:

Chemical Composition of Table 250CrVA

(2) Measuring the depth of decarburization layer

The depth of the decarburization layer should comply with the provisions of GB1222-84 for different materials and different diameters of spring materials, because the depth of the decarburization layer is the main parameter basis for reducing the strength of raw materials, fatigue strength and hardenability.

(3) Control the content of non-metallic inclusions

There are oxides and silicates in the metal structure, which seriously reduce the strength of the material and increase brittle fracture. Therefore, non-metallic inclusions should be controlled not to exceed 2.5 grades, and the average diameter of other impurities should be below 10 μm.

Through the above material detection and analysis of the imported coil spring 1, its mechanical properties are close to the domestic 50CrVA. We choose 50CrVA cold-rolled narrow strip steel with different thickness specifications as the raw material for the development of the coil spring 1.

1. The structure of the sleeve coil spring 1

The sleeve coil spring 1 is composed of 8 reeds with different sizes. : 55mm, center layer diameter They are: 45.8mm, 48mm, 50mm, 53.1mm, 56.78mm, 60.88mm, 64.94mm, 69.82mm, and the opening width h are: 32mm, 32mm, 31.2mm, 31.78mm, 31.8mm, 31.88mm, 31.94mm, 38.14mm.

Since the eight reeds have the same shape but different sizes, their forming process is the same, so one of them can be selected to study its forming process, and the other reeds can be manufactured according to this method. Select the innermost slice as the research object.

Its size is, thickness t=1.24mm, width b=55mm, central layer diameter d=45.8mm, opening width h=32mm, according to the above data, the size of the blank for making the reed can be calculated by the following formula: because Substituting the known dimensions into the above formula, we can calculate α=44.32°, so the length of the reed blank is

宽为b＝55mm，所以该坯料的面积A＝L*b＝108.4*55＝5962mm²。

The width is b=55 mm, so the area of the blank is A=L*b=108.4*55=5962 mm ² .

Therefore, after the above process analysis, the shape and size of the blank can be obtained.

3. Structural design of the bending die

The structural design of the bending die should be carried out on the basis of the process plan of the selected bending parts. In order to ensure that the requirements of the workpiece are met, the following points must be paid attention to in the structural design of the bending die:

1) The billet should be placed on the mold to ensure reliable positioning;

2) During the bending process, the blank should be prevented from sliding;

3) In order to reduce the rebound, the workpiece should be corrected in the mold at the end of the stroke;

4) The structure of the bending die should take into account the possibility of reducing springback during manufacturing and maintenance;

5) It is convenient to put the blank into the mold and take it out from the mold after bending.

The design features of this mold: In order to make the whole circle fuller, a top block 2 is designed on the upper mold 3. Since the bending moment distribution of the blank is not uniform, it can withstand it at a certain moment before the end of the process. The end of the billet prevents it from slipping along the surface of the upper die 3, so that the billet will have a tendency to bend back and round, and improve the quality of the shape. Moreover, the rolling die has a simple structure and is easy to process; parts processed by the process and the die have high precision, which can make up for the low precision of conventional processing, and are especially suitable for processing on continuous dies.

4. Assembly process of shock absorber sleeve coil spring

Assembly process equipment is an important means to ensure the quality of product assembly. A special assembly mold is designed for the assembly of the sleeve coil spring 1 to meet the assembly gap between the reed and the entire reed. Strict requirements on group concentricity and curvature of each reed.

The characteristics of this assembly mold are: there is a ring-shaped hub on the outside, which can well fix a set of coil springs, and there are three arc-shaped cores in the middle to squeeze a set of coil springs to obtain a suitable gap. The middlemost one is an inverted conical core, which applies force to the arc-shaped core to squeeze the coil spring 1 group by pressing it downwards. Through such a set of molds, both the gap between the sheets and the outer diameter of the entire spring group can be guaranteed.

5. Heat treatment of coil spring 1

It is a technical difficulty of the present invention to realize the stiffness characteristic requirement of coil spring 1, and each spring group is required to meet the required amount of deformation under a prescribed load. The most important way to realize it is the heat treatment process of quenching and tempering, and the coil spring Group 1 is composed of multiple pieces of reeds with different thicknesses. Its structural characteristics also have special requirements for the formulation of heat treatment process. If the heat treatment process is improper, problems such as quenching cracks or insufficient quenching, and severe decarburization of the surface will easily occur, resulting in reeds In use, the stiffness characteristics cannot be guaranteed, and local scratches appear, resulting in failure problems such as uneven wear.

Due to the special structure of coil spring 1, we have carried out two heat treatment methods on it: single reed heat treatment and whole reed set heat treatment. After the heat treatment test, in terms of the performance and appearance of the structure, the single-piece heat-treated spring steel has a better structure and higher performance.

Secondly, we test and analyze the mechanical properties of coil spring 1 after heat treatment:

(1) testing the elastic properties of coil spring 1 after two kinds of heat treatment

Figure 4 shows a schematic diagram of the results of mechanical performance testing and analysis of the heat-treated coil spring 1. It can be seen from the figure that the displacement of the multi-plate coil spring 1 under pressure after combined heat treatment is relatively small, indicating that its hardness is relatively high, and its elasticity is relatively high. It is less elastic than the heat treatment of single coil spring 1.

(2) Test impact performance

The impact load refers to the load applied to the sleeve parts at a higher speed. When the sleeve coil spring 1 is subjected to the impact load, the stress and deformation caused by the instantaneous impact are much larger than the static load. Therefore, in the manufacturing When choosing coil spring 1, it is necessary to take into account the impact load capacity of the material, that is, the impact performance of the material.

Through experiments, we found that the damaged throw height of the single-piece coil spring 1 is higher, indicating that its impact performance is better, that is, its ability to withstand stress is better, and it is more in line with our higher toughness requirements.

(3) Hardness measurement of coil spring 1

Table 3 Hardness test value of single coil spring 1

frequency 1 2 3 4 average value value 53.2 52.8 52.8 53.0 53.0

Table 4 The hardness test value of assembled coil spring 1

frequency 1 2 3 4 average value value 54.5 54.6 54.2 54.6 54.5

Through calculation, the hardness value of the single coil spring 1 after heat treatment is 53HRC, and the hardness value of the multi-plate coil spring 1 after heat treatment is 54.5HRC, which is slightly higher than the previous hardness, and the difference is not too large. The HRC hardness required by the spring is between 50 and 54, and the coil spring 1 of the two heat treatment methods basically meets the use requirements.

The present invention bends a single reed by adopting a reed bending die with high dimensional accuracy and good surface quality, which ensures the concentricity and curvature of multiple reeds of unequal thickness, and uses extrusion assembly dies to complete the bending process of the reed. The assembly ensures the rationality of the assembly gap between the reeds, ensures the accuracy of the coil spring assembly, fills a gap in the diesel engine industry in my country, and strengthens the domestic research and development of high-performance diesel engine shock absorber coil springs. The capacity has improved the production and preparation level of shock absorber sleeve coil spring.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (3)

1. a manufacture method for sleeve coil spring for damper, is characterized in that, the method comprises the following steps:

The original paper of import sleeve coil spring is carried out to the detection analysis of material, select the raw material of development wind spring;

According to the analysis to sleeve coil spring structure, determine shape and the size of blank;

Adopt bending mould to carry out bending volume circle to blank, the reed obtaining is heat-treated one by one;

Utilize press fit mould, reed is assembled into sleeve coil spring;

The bending mould of described manufacture method application comprises: kicker, patrix, volume circular hole, counterdie;

Described kicker is arranged on the hole slot of described patrix, and described volume circular hole is arranged on the top of described patrix and described counterdie.

2. the method for claim 1, is characterized in that, the described detection analysis of the original paper of import sleeve coil spring being carried out to material, and the raw-material implementation method of selecting development wind spring is:

Be 25 ℃ in room temperature, under the testing conditions that humidity is 48%, by full spectrum direct current ICP spectrometer, infrared carbon sulfur analyzer, the original paper of import sleeve coil spring carried out to material tests analysis, the raw material of preliminary selected development sleeve coil spring;

Measure selected raw-material decarburized layer deepness, make it meet the requirement to unlike material different-diameter spring material;

Measure and control the content of sonims in selected materials, make sonims must not exceed 2.5 grades, other foreign material average diameters are below 10 μ m;

Selector closes the raw material of above-mentioned requirements as the object of development, otherwise again selectes raw material and measure, and it is met above-mentioned to raw-material requirement.

3. the manufacture method of sleeve coil spring for damper as claimed in claim 1, is characterized in that, the top of described kicker is the circular arc tangent with described volume circular hole.

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