Knowledge on Hardware Spring
2017-01-04
Hardware spring makes use of its deformation to generate power or store energy.
Main functions: ① control mechanical movement, e.g., valve spring of combustion engine, control spring of clutch, etc.; ② absorb vibration and impact energy, e.g., buffer spring under automobile and train carriage, absorption spring of coupling, etc.; ③ store and output the energy as power, e.g., springs of clocks, firearms, etc.; ④ use as dynamometric elements, e.g. springs of dynamometer, spring scale, etc. The ratio of load and deformation of the spring is called “spring rate”; the bigger the spring rate is, the harder the spring is.
By mechanical properties, spring is divided into extension spring, compression spring, torsional spring and bending spring. By shapes, spring is divided into spiral spring, disc spring, leaf spring, plane volute spring, torsion spring, etc. Common cylindrical helical spring has a simple structure and can be made into all types according to its spring load, so it is widely applied. Generally speaking, the spring materials have high elastic limit, fatigue limit, impact strength, good heat treatment property, etc., such as carbon, alloy, stainless steel, copper alloy, nickel alloy, rubber, etc. The manufacturing methods include cold rolling and hot rolling. The spring wire with a diameter less than 8 mm uses the cold rolling, and more than 8mm, hot rolling. Some springs must adopt forcing or shot blasting treatment, enhancing loading capacity of the spring.
Spring is an elastic element widely applied to machinery and electronic industry. When spring is loaded, spring generates big elastic deformation to turn mechanical work or kinetic energy into deformation energy; when spring is unloaded, spring restores to turn deformation energy into mechanical work or kinetic energy;
Main functions of spring: ① measure the force, e.g., springs of spring scale, dynamometer, etc.; ② control movement, e.g., control springs of clutch, brake, valve, etc.; ③ vibration damping and cushion, e.g., springs of bumper, absorber, etc.; ④ store or output energy, e.g., springs of clocks, instruments, automatic control mechanism, etc.
2. Spring types: compression spring, extension spring, torsional spring, wire forming, etc.
3. Name and Size of Spring Parts:
(1). Diameter of Spring Wire (d): the diameter of the spring wire;
(2). External Diameter of Spring (D): the maximum external diameter of the spring;
(3). Internal Diameter of Spring (D1): the minimum external diameter of the spring;
(4). Mean Diameter of Spring (D2): the mean diameter of the spring; calculation formula: D2 = (D+D1)÷2 = D1 + d = D - d
(5). t: the axial distance on the pitch diameter between corresponding points of adjacent coils is pitch.
(6). Effective Coil Number (n): the coil number that the spring can holds same pitch;
(7). Supporting Coil Number (n2): in order that the spring bears the stress evenly when working to guarantee vertical end surface of axes, tighten the ends of the spring when manufacturing. The tightened coil numbers act supporting action, and are called “Supporting Coils”. Generally speaking, it is 1.5T, 2T and 2.5T. 2t is frequently used.
(8). Total Coil Number (n1): the sum of effective coil number and supporting coil number, that is, n1=n+n2.
(9). Free Height (H0): the height that the spring bears no external forces. Calculation formula: H0=nt+(n2-0.5)d=nt+1.5d (n2=2)
(10). Spring Spread Length (L): the length of the required wire. L≈n1 (ЛD2) 2 + n2 (pressure spring) L=ЛD2 n + hook spread length (tension spring).
(11). Direction of Spiral: leaf spiral and right spiral; it is usually right spiral; if the drawing doesn’t specify, it is generally right spiral.
4. Specified Drawing of Spring
(1). On the view of parallel spiral spring wire, the contour lines of coils are straight lines.
(2). The spring having effective coil numbers more than 4 coils is drawn 1-2 coils at its two ends (not including supporting coils). The center is connected the points through the center of spring wire with lines.
(3). On the drawing, the spiral direction of the spring isn’t specified, the spiral spring must be drawn into the right spiral; and the left spring is also drawn into the right spiral, but it must be specified “Left”.
Main functions: ① control mechanical movement, e.g., valve spring of combustion engine, control spring of clutch, etc.; ② absorb vibration and impact energy, e.g., buffer spring under automobile and train carriage, absorption spring of coupling, etc.; ③ store and output the energy as power, e.g., springs of clocks, firearms, etc.; ④ use as dynamometric elements, e.g. springs of dynamometer, spring scale, etc. The ratio of load and deformation of the spring is called “spring rate”; the bigger the spring rate is, the harder the spring is.
By mechanical properties, spring is divided into extension spring, compression spring, torsional spring and bending spring. By shapes, spring is divided into spiral spring, disc spring, leaf spring, plane volute spring, torsion spring, etc. Common cylindrical helical spring has a simple structure and can be made into all types according to its spring load, so it is widely applied. Generally speaking, the spring materials have high elastic limit, fatigue limit, impact strength, good heat treatment property, etc., such as carbon, alloy, stainless steel, copper alloy, nickel alloy, rubber, etc. The manufacturing methods include cold rolling and hot rolling. The spring wire with a diameter less than 8 mm uses the cold rolling, and more than 8mm, hot rolling. Some springs must adopt forcing or shot blasting treatment, enhancing loading capacity of the spring.
Spring is an elastic element widely applied to machinery and electronic industry. When spring is loaded, spring generates big elastic deformation to turn mechanical work or kinetic energy into deformation energy; when spring is unloaded, spring restores to turn deformation energy into mechanical work or kinetic energy;
Main functions of spring: ① measure the force, e.g., springs of spring scale, dynamometer, etc.; ② control movement, e.g., control springs of clutch, brake, valve, etc.; ③ vibration damping and cushion, e.g., springs of bumper, absorber, etc.; ④ store or output energy, e.g., springs of clocks, instruments, automatic control mechanism, etc.
2. Spring types: compression spring, extension spring, torsional spring, wire forming, etc.
3. Name and Size of Spring Parts:
(1). Diameter of Spring Wire (d): the diameter of the spring wire;
(2). External Diameter of Spring (D): the maximum external diameter of the spring;
(3). Internal Diameter of Spring (D1): the minimum external diameter of the spring;
(4). Mean Diameter of Spring (D2): the mean diameter of the spring; calculation formula: D2 = (D+D1)÷2 = D1 + d = D - d
(5). t: the axial distance on the pitch diameter between corresponding points of adjacent coils is pitch.
(6). Effective Coil Number (n): the coil number that the spring can holds same pitch;
(7). Supporting Coil Number (n2): in order that the spring bears the stress evenly when working to guarantee vertical end surface of axes, tighten the ends of the spring when manufacturing. The tightened coil numbers act supporting action, and are called “Supporting Coils”. Generally speaking, it is 1.5T, 2T and 2.5T. 2t is frequently used.
(8). Total Coil Number (n1): the sum of effective coil number and supporting coil number, that is, n1=n+n2.
(9). Free Height (H0): the height that the spring bears no external forces. Calculation formula: H0=nt+(n2-0.5)d=nt+1.5d (n2=2)
(10). Spring Spread Length (L): the length of the required wire. L≈n1 (ЛD2) 2 + n2 (pressure spring) L=ЛD2 n + hook spread length (tension spring).
(11). Direction of Spiral: leaf spiral and right spiral; it is usually right spiral; if the drawing doesn’t specify, it is generally right spiral.
4. Specified Drawing of Spring
(1). On the view of parallel spiral spring wire, the contour lines of coils are straight lines.
(2). The spring having effective coil numbers more than 4 coils is drawn 1-2 coils at its two ends (not including supporting coils). The center is connected the points through the center of spring wire with lines.
(3). On the drawing, the spiral direction of the spring isn’t specified, the spiral spring must be drawn into the right spiral; and the left spring is also drawn into the right spiral, but it must be specified “Left”.