Spring is a kind ofelasticTo work on the mechanical parts.The parts made of elastic materials deform under the action of external force, and recover after removing the external force.Also called "spring".It is generally made of spring steel.The types of springs are complex and diverse. According to their shapes, they mainly include spiral springs, scroll springsPlate spring, special-shaped spring, etc.
Chinese name
Spring
Foreign name
Spring
Materials
Parts made of elastic materials under external force
Like most other basic mechanisms, metal springs have existed for a long time in the Bronze Age.Even metal, wood is used as a structural member of a flexible bow and military catapult.stayRenaissanceFor the first time, the precise spring is inevitable because of the accurate clock and watch.The 14th century saw the development of revolutionary astronomical navigation with accurate clocks.The exploration and conquest of the world by the European colonial powers continued to provide impetus to the clockmaker "Science and art. Another field of firearms was to promote the development of springsindustrial revolutionAt the moment, the idea of large, accurate and cheap springs was proposed.As clockmakers' springs are often manufactured by hand, the springs are made of piano steel wire or similar materials in mass production.Advanced manufacturing methods make the spring ubiquitous.Computer control line andPlate bending machineIt is allowed to customize the processing of springs, which is obviously a special machine.The spring is just aAccumulatorIt has the function of storing energy, but it cannot release energy slowly. To achieve this function, we should rely on "spring+large transmission ratio mechanism", which is common in mechanical watches.Springs have been used for a long time. Ancient bows and crossbows are two kinds of springs in a broad sense.The inventor of spring should be a British scientist strictlyHooke(Robert Hooke). Although the spiral compression spring has appeared and been widely used at that time, Hooke proposed“Hooke's law”- The elongation of the spring is proportional to the size of the force applied. According to this principle, in 1776Helical compression springThe spring scale of.Soon, Hooke himself invented the spring made according to this principle, which is specially used for clocks and watches.The spring that conforms to Hooke's Law is the real spring.Belleville spring, invented by French Belleville, is a washer type spring with truncated cone section made of metal sheet or forging blank.After the emergence of modern industryBelleville springIn additionGas spring, rubber spring, scroll spring, mold springStainless steel spring、Air spring、Memory alloySpring and other new springs.[1]
For the spring industry, the supply of low-grade ordinary springs has exceeded the demand for a long time, and the supply of high-grade products (high-strength, high stress, heterosexual parts, special materials) has exceeded the demand for a long time.The output of China's spring industry has become saturated. According to experts' statistics, China's annual production of springs has reached 4 billion pieces. There are 21 categories and more than 1600 varieties of various spring products, mainly including valve springs, suspension springs, diaphragm springs, damping springs, hydraulic springs, oil pump springs, disc springs, high-temperature springs, circlips, tension springs, torsion springs, compression springsScroll spring and anisotropic spring, etc.The spring industry developed relatively fast during the "Eighth Five Year Plan" and the "Ninth Five Year Plan", especially in Shanghai, Tianjin, Guangzhou, Shandong, Changchun, Chongqing and other regions. Other regions also developed to varying degrees, which is better than other industries in general.Automobiles, motorcycles, mopeds, internal combustion engines, electrical appliances, instruments, etc. need to be developed. The development of these industries will drive the development of the spring industry.faceMacroeconomic situationThe contradiction of low product quality, loose organizational structure and weak development ability formed by the industry's long-term accumulation has become more prominent. From a deeper perspective, mainly problems in the market, system and mechanism, the industry insight researcher believes that with the transformation of the national economy from the seller's market to the buyer's market, some deep-seated contradictions,In particular, structural contradictions accumulated over the years have become increasingly prominent.The current unreasonable industrial structure is manifested as follows: excess production capacity in some industries and unreasonable product structure;The technical structure is unreasonable, and the level of major industrial equipment is low;The enterprise organization is small and scattered, lacks competitive strength and advantages, and the regional structure tends to converge, failing to reflect comparative advantages and collaboration benefits.[1]
development
Although the spring industry is a small industry in the whole manufacturing industry, its role cannot be underestimated.The country's industrial manufacturing and automobile industries need to accelerate their development, and the spring industry, as one of the basic parts and components, needs a super early stage of development to adapt to the rapid development of the country's entire industry.In addition, the expansion of the scale and variety of spring products and the improvement of the quality level are also the needs of the upgrading of mechanical equipment and the improvement of the performance of the supporting host. Therefore, spring products play an important role in the development of the entire national industry.The commodity industry and hardware industry, including lighters, toys, locks, door hinges, fitness devices, mattresses, sofas, etc., have the largest demand for springs in terms of quantity, tens of billions of pieces, low technical requirements, and very low prices. They are generally produced by small spring factories scattered around the country. They have unique advantages in cost, and it is difficult for large spring factories to compete with them.As a result, new spring enterprises are born from time to time. In the future, market demand will grow at an annual rate of 7%~10%.After China's entry into WTO, the export volume of domestic hardware products has increased significantly, and the demand for springs has been driven accordingly. However, the international market has its uncertainty due to the influence of the demand in the international market and trade barriers.[1]
Elasticity formula
Announce
edit
F=kx, where F is elastic force, k is stiffness coefficient (or obstinacy coefficient), and x is the length of spring lengthening (or shortening).Example 1: Use 5N force to pull a spring with a stiffness coefficient of 100N/m, and the spring will be lengthened by 5cm Example 2: When a spring is pulled by 10N force, the total length is 7cm, and when it is pulled by 20N force, the total length is 9cm. Calculate the force when the original length and extension are 3cm?[1]
Structure classification
Announce
edit
Springs can be divided intoTension spring、Compression spring、Torsion springAnd bending spring, which can be divided intoBelleville spring、Annular spring、Plate spring, coil springTruncated cone scroll projectileSpring andTorsion bar springAccording to the manufacturing process, it can be divided into cold coil spring and hot coil spring.ordinaryCylindrical springBecause of its simple manufacture, various types can be made according to the loading conditions, and its simple structure, it is widely used.Generally speaking, the manufacturing materials of springs should have high elastic limit, fatigue limit, impact toughness and goodheat treatmentProperties, such as carbon spring steelAlloy spring steelStainless spring steel, copper alloy, nickel alloy and rubber, etc.The manufacturing methods of spring include cold coiling method and hot coiling method.The cold coiling method is generally used for spring wires with a diameter of less than 8 mm, and the hot coiling method is used for wires with a diameter of more than 8 mm.Some springs are forced orShot peening, which can improve the bearing capacity of the spring.[1]
Springs can be divided into the following 6 categories:
1. The torsion spring is a spring that bears torsion deformation, and its working part is also closely wound into a spiral shape.The end structure of the torsion spring is a torsion arm processed into various shapes, rather than a hook ring.The torsion spring uses the lever principle to twist or rotate the elastic material with soft material and greater toughness, so that it has great mechanical energy.2. The tension spring is a coil spring that bears the axial tension.When not under load, the coils of the extension spring are generally tight without clearance.3. The compression spring is a spiral spring that bears axial pressure. Its material section is mostly circular, and it is also made of rectangular and multi strand steel. The spring is generally of equal pitch. The shape of the compression spring is cylindrical, conical, convex, concave and a small amount of non-circular. There will be a certain gap between the coils of the compression spring,When subjected to an external load, the spring shrinks and deforms, storing deformation energy.4. Progressive spring, which adopts a design with inconsistent thickness and density, has the advantage that when the pressure is not large, the undulation of the road surface can be absorbed through the part with lower elastic coefficient to ensure the riding comfort. When the pressure increases to a certain extent, the spring in the thicker part plays the role of supporting the body. The disadvantage of this spring is that the handling feeling is not direct and the accuracy is poor.5. Linear spring: the thickness and density of the linear spring from top to bottom are unchanged, and the elastic coefficient is a fixed value.This designed spring can make the vehicle obtain more stable and linear dynamic response, which is conducive to the driver's better control of the vehicle. It is mostly used for performance oriented modified vehicles and competitive vehicles. The disadvantage is of course that the comfort is affected.6. Short spring Short spring is shorter than the original spring, and more[1]
Air spring
Robust, short spring installed, can effectively reduce the center of gravity of the body, reduce the roll produced during cornering, make cornering more stable and smooth, and improve the vehicle's cornering maneuverability.The damping setting of the original shock absorber is more comfortable, so the short spring and the original shock absorber are not very stable in cooperation. It can not effectively restrain the rebound and compression of the short spring. When driving on bumpy roads, there will be an uncomfortable feeling of jumping. In the long run, the life of the shock absorber will be greatly shortened, and there may be oil leakage.Of course, the above conditions are relatively speaking. There will be no such serious damage during daily driving, and you should try not to drive hard. After all, the original shock absorber cannot withstand high load pressure.[1]
Torsion spring
Torsion spring
Torsion spring（Torsion spring）The principle of lever is used to twist or rotate the elastic material with soft material and high toughness to make it have great mechanical energy.It is a spring subject to torsional deformation, and its working parts are also closely or separately surrounded.The end structure of the torsion spring is a torsion arm that is processed into various shapes. The deformation of the torsion arm from single torsion to double torsion and even various torsion bars can be shaped according to the design.Torsion springs are commonly used as balancing mechanisms in machinery, and are widely used in industrial production such as automobiles, machine tools, and electrical appliances.[1]
Compression spring
Compression spring
Compression spring（Compression spring）It is a spiral spring that bears axial pressure. Springs are generally divided into constant pitch springs and variable pitch springs. The shapes of compression springs are cylindrical, conical, convex, concave, and a small amount of non-circular. There is a certain gap between the coils of compression springs. When subjected to external load, the spring shrinks and deforms, storing deformation energy.Variable pitch springs are more and more common, not just equal pitch springs, but variable pitch springs can play different roles in different environments.[1]
Carbon nanospring
The diameter of carbon nanotube spring can reach hundreds of microns, while the length can reach several centimeters. Its spinning structure has broad application prospects, and is expected to be used in flexible conductors, flexible electrodes, micro strain sensorsSupercapacitor, integrated circuits, solar cells, field emission sources, energy dissipating fibers and other fields, which provide the possibility to prepare carbon nanotube electronic devices visible to the naked eye, and are also expected to be used in medical devices, such as tension sensing bandages.This new structure can also be developed into multifunctional carbon nanotube fiber composites for use.[1]
Tension spring
Tension spring（drag spring）It is a spiral spring that bears axial tension, and the tension spring is generally made of circular section materials.When not under load, the coils of the extension spring are generally tight without clearance.It is widely used in machines and instruments by using the rebound force after stretching (to control the movement of the machine parts, store energy, measure the force, etc.). Its hook forms include side hook tension spring, long hook tension spring, British hook tension spring, German hook tension spring, semicircular hook tension spring, duckbill hook tension spring, etc. Its materials include stainless steel, piano steel, high carbon steel, phosphor copper, beryllium copper, oil temperingAlloy spring steelEtc.[1]
Air spring
Spring
Air spring is a non-metallic spring that adds pressure air into a flexible closed container, and uses the compressibility of air to achieve elastic effect. It can be roughly divided into two types: capsule type and membrane type. Air spring has excellent elastic characteristics, which can greatly improve the smoothness of the vehicle when used in the suspension device of high-end vehicles, thus greatly improving the comfort of vehicle operation,Therefore, air spring has been widely used in automobiles and railway locomotives.In addition, air springs have many advantages over ordinary steel springs, so they are also used in some mechanical equipment, precision instruments[1]
Manufacturing process
Manufacturing equipment
As an important element in the industrial system, the spring has a large amount of use and a wide range of types, so the production of the spring has gradually moved from the original manual production to automation.Ninety years ago in China, there were only a few mechanical equipment specialized in producing springs in the spring industry. As the spring market became larger and larger, more and more professional spring equipment enterprises entered China. For example, Taiwan's Northeast Spring Machinery (EN Qiaoding), Guanghong (KHM), etc. gradually occupied the mainstream spring production market.EN502 universal machine in Northeast China[1]
Spring manufacturing equipment
It adopts proprietary mechanical mechanism to produce various springs and special-shaped elastic elements conveniently and quickly.Guanghong's equipment is a high-speed equipment for producing compression spring and tension spring.There are also many professional spring equipment manufacturers abroad, such as Wafios, MEC (now ORII&MEC), etc.Domestic production of large-scale spring CNC hot coiler is still blank.Although the spring industry is a small industry in the whole manufacturing industry, its role cannot be underestimated.The expansion of spring production and marketing scale, the increase of variety, and the improvement of quality level are also the needs of upgrading mechanical equipment and improving the performance of supporting host.Therefore, spring products have played an important role in the industrial development of the whole country.Since the reform and opening up, with the economic globalization and the establishment of China's manufacturing power status, the demand for supporting springs has soared.In addition, the investment in spring production is not high, the technical threshold is low, and the investment recovery is fast. Since the 1980s, the number of spring production enterprises has increased rapidly.by[1]At the end of 2010Enterprises above designated sizeThere are 724, with more than 100000 employees. In 2010, the sales revenue exceeded 30 billion yuan, and the total profit exceeded 1.6 billion yuan.Springs are highly competitive products. In the market, low-end products, domestic enterprises have cost advantages and certain price competitiveness. High end products, foreign capital and joint venture technology have advantages. Advanced products, such as flexible stents for the treatment of cardiovascular diseases, are almost monopolized by foreign medical giants, and domestic enterprises do nothing.Automobile spring is the hottest area for domestic and foreign enterprises to compete in the market. Domestic and foreign enterprises have their own strengths and are inseparable from each other.The spring industry has gradually entered into the competition of the industrial chain from the price war and service competition in the past, and the industrial chain is completed by means of standardization.Although the standard system of this industry is relatively complete, due to the early formulation, the market demand is quite far away, especially compared with developed countries such as Japan, Europe and the United States, the current national standards and industry standards are still low, resulting in the weak competitiveness of domestic spring products in the international market. Therefore,It is the most important issue for the industry to issue new industry standards that are in line with international standards as soon as possible.During the "12th Five Year Plan" period, thanks to the relevant national policy stimulus and the revitalization plan of related industries, China's automobile, railway, instrumentation and other industries will maintain rapid and stable development.In addition, some emerging industries, such as conventional weapons, nuclear power and aircraft manufacturing, cannot lack the participation of springs. With China's growing national strength, defense technology investment is increasingly abundant, which is also an important aspect of the spring industry business opportunities.Under the background of good external environment and stable growth of downstream demand, China's spring industry will maintain rapid and stable development. It is expected that by the end of the "12th Five Year Plan", i.e. 2015, the sales of China's spring industry is expected to reach 60 billion yuan.[1]
Spring
Cold forming
1) The cold forming process can be automated at one time.The cold forming machine has developed to 12 claws.The steel wire within the range of (0.3~14) mm can be formed at one time in the 8-jaw forming machine.Development direction of forming process equipment: ① improve the forming speed, and the main development trend is to improve the forming speed of equipment, that is, consumption efficiency; ②Improve the durability of equipment by improving the fineness of equipment parts and strengthening the heat treatment effect; ③increaseLength sensorandLaser range finder, stop the CNC forming machine automaticallyclosed-loop control Manufacturing process.2) The range of cold forming process can be.Spring coiler with large wire diameter, the maximum specification can reach 20mm,=2000MPa, and the winding ratio is 5.The cold forming process of reducing or equal diameter Mini Block spring and eccentric spring still has limitations.[1]
Thermoforming
1) Hot forming process speed can only be.In China, there is only CNC 2 axis hot spring coiling machine for forming on the (9~25) mm specification, with the maximum speed of 17 pieces per minute.Compared with the prosperous countries, there is a big gap.2) Large spring hot forming process control ability.Since there is only CNC 2 axis hot spring coiling machine, the shape control has less three directions and poor accuracy;And there is no automatic bar rotation control and adjustment mechanism, so the forming process and ability of hot coil spring are low.Therefore, the accuracy and surface oxidation decarburization degree of the spring are also low.[1]
Spring function
major function
① Control the movement of machinery, such asinternal-combustion engineValve spring in, control spring in clutch, etc. ②Absorb vibration and impact energy, such as those under cars and trainsBuffer spring、coupling Vibration absorption spring, etc. ③Store and output energy as power, such as clock spring, gun spring, etc. ④It is used as a force measuring element, such as a force measuring device, a spring in a spring scale, etc.The ratio of load and deformation of the spring is called spring stiffness. The greater the stiffness, the harder the spring will be.The spring is a kind of elastic element widely used in the mechanical and electronic industries. When the spring is loaded, it can produce largeelastic deformation , the mechanical work or kinetic energy is converted into deformation energy, and the deformation of the spring disappears and returns to the original state after unloading, and the deformation energy is converted into mechanical work orkinetic energy。[1]
Measurement function
We know thatElastic limitInside, the extension (or contraction) of the spring is proportional to the external force.The spring scale is made by using the property of spring.[1]
Reset function
The spring deforms under the action of external force. After the external force is removed, the spring can recover.Many tools and equipment are reset by spring.For example, many buildingsHingeThe door will automatically reset after people enter and exit with reset springs.People also use this function to make automatic umbrellasmechanical pencilIt is very convenient.In addition, all kinds of buttons and keys also need return springs.[1]
Driving function
Mechanical clocks and clockwork toys are driven by tightening the clockwork.When the spring is tightened, it will bend and deform, and a certain amount ofElastic potential energy。After release, the elastic potential energy changes intokinetic energy, driven by the transmission device.In the toy gun andstarting gunAnd military guns also use one of the properties of springs to work.[1]
Buffer function
A spring is installed between the frame and the wheel of the locomotive and automobile, and the elasticity of the spring is used to slow down the bumping of the vehicle.[1]
Phonation function
When air comes from the reed in harmonica and accordionIn holeWhen flowing, the reed is impacted, and the reed vibrates to make a sound.[1]
Compression function
When observing various electrical switches, it can be found that one of the two contacts of the switch must be equipped with a spring to ensure that the two contacts are in close contact and have good continuity.If the contact is poor, the resistance at the contact will increase, and the heat generated when the current passes through will increase. In serious cases, the metal at the contact will melt.The two metal columns of the bayonet lamp holder are equipped with springs for good contact;As for the central metal sheet of the screw lamp cap and the insertion metal sheet of all sockets, they are all reed sheets, whose function is to make both sides contact closely to maintain the same good.In the cassette tape, there is a phosphor bronze reed, which is produced when it is bent and deformedelastic forceKeep the head in close contact with the tape.There is a long spiral spring in the stapler. On the one hand, it is used to push the staples tightly. On the other hand, when the front nails are pushed out, the back nails can be sent to the front for comfortable push out. In this way, the nails can be pushed to the front automatically until all the nails are pushed out.Many machines feed automatically,Automatic rifleThe automatic loading of bullets in is all dependent on this function of the spring.In addition, like clothes clipClip，ball penThe clip on the pen cover is clamped on the clothes by the spring compression function.[1]
Due to the limitation of product structure, multi strand spring generally has the characteristics of high strength and good performance.It is required that the materials shall beSpring strengthAnd toughness.During the processing of the multi strand spring, attention should be paid to the following: 1. According to the product requirements, the support ring can be cold and hot merged.It is not allowed to heat the spring to spark or whiten by hot combination, and the temperature of silicon manganese steel shall not be higher than 850 ℃.The bearing ring and the effective ring shall be in effective contact, and the clearance shall not exceed 10% of the nominal clearance between rings.2. The characteristics of the multi strand spring can be determined by the adjustment lead, and the cable pitch can be adjusted when winding.The screw pitch can be 3~14 times the wire diameter, but generally 8~13 times is preferred.Its spring force is also closely related to free height, parallel end ring, outer diameter and wire performance, which can be changed by adjusting one or more of them.3. Spring without supporting ring and spring with too thin steel wire diameter shall not be welded with spring head, but the end wire rope shall not be obviously loose and shall be deburred.For multi strand springs with welded heads, the length of the welding part shall be less than 3 times the cable diameter (the longest shall not be more than 10mm).The heating length shall be less than one circle, and shall be polished smoothly after welding. During gas welding, the welding parts shall be subject to local low temperature annealing.4. The spring surface can be treated by phosphating generally, and other treatments can also be carried out.When zinc and cadmium are to be coated, hydrogen removal treatment shall be carried out after electroplating. After hydrogen removal, 3% (not less than 3 pieces) shall be sampled for retest and standing treatment. No fracture is allowed in the retest.The surface dirt, salt stain and oxide skin of the spring shall be removed by sand blowing or gasoline cleaning, but acid cleaning is not allowed.5. ImportantSpringThe compression time is 24 hours, and the ordinary spring is compressed for 6 hours or 3~5 consecutive times, each time for 3~5 seconds.When pressing, the clearance between the spring and the mandrel should be 10% of the mandrel diameter. If the clearance is too small, it is difficult to operate. If the clearance is too large, it is easy to bend the spring.If one of the springs breaks during compression, the rest shall be reprocessed.[1]
