Gas Springs and Dampers

Transcription

1 Gas Springs and Dampers for Automotive Applications... t e c h n o l o g y g i v e s c o m f o r t

2 STABILUS A Company with Innovative Tradition Choosing and Selecting Gas Springs State of the art Product development Pioneer Performance Ever since the company was founded in Koblenz in 1934, STABILUS has been involved in hydraulic damping elements for automotive applications. For example, the first horizontally acting damper was used as a steering damper in millions of applications. In 1962, STABILUS presented the first gas spring manufactured in series production in the world. To date, more than 1.2 billions of those have been produced. With its gas spring and hydraulic vibration damper product lines, STABILUS is the world market leader with an annual production of more than 100 million units. Worldwide Activities With a global sales and service network and 10 production sites in Europe, USA, Mexico, Brazil, New Zealand, Australia and Korea, STABILUS supplies and serves more than 2,000 customers worldwide. Stabilus designs and builds all of its own production machinery Continuous quality control in our own test labs Customer Satisfaction Customer requirements and satisfaction, development know-how, speed, and service are major company goals. STABILUS is known for technical innovation, quality, and competitive pricing at all levels. Gas Springs and Dampers for Automotive Applications Highest quality, sound know-how, userspecific coordination and a high level of functional comfort provide new opportunities for installing STABILUS products in automobiles. e.g., trunk lid... Gas springs make opening and closing the trunk lid or tailgate safe and easy, with a defined speed curve. e.g., hood... Hoods open easily with the help of gas springs; they replace awkward hood props and prevent dirty hands. e.g., seat adjustment... Whether seat height, seat position, or back rest adjustment, gas springs and dampers provide comfort and safety. e.g., vibration damping... Dampers used as steering dampers or as belt tensioning dampers provide the desired smooth running, safety and comfort. Optimum training in our own training centers Development Supplier For decades, STABILUS has been supplying the international automotive industry as a recognized development supplier. The service ranges from support in the area of design and development, including all customary CAD activities and standardcompliant specification processes, to excellent development and coordination support through efficient and fast sample design. Highest Quality As the leading gas spring supplier worldwide, our quality management system certainly fulfills the high quality requirements of international standards, such as DIN EN ISO 9001 and the new world standard ISO/TS including the requirements as per QS 9000, VDA 6.1, EAQF and AVSQ. Protected Environment Our production processes make environmentally friendly manufacturing a high priority. Its success is documented by the successful certification of the environment management system in compliance with DIN EN ISO Logistics Partner The highest level of flexibility is needed if a supplier is to fulfill the requirements resulting from the just-in-time philosophy of the automotive industry. For years, STABILUS has been practicing this very successfully and uses state-of-the-art production and communication systems for efficient coordination with our partners at all levels. Function of Your Choice In automotive applications, most gas springs are specially matched and selected for each vehicle model. The function of the gas spring and the comfort of the application are determined by many characteristics, which can be accurately defined prior to series introduction. Naturally, STABILUS application engineers are ready to support and consult, drawing on their many years of experience, their combined know-how, and customized samples. The most important of these variables are presented here: Extension Force For gas springs to open an application easily and to close it safely, their extension force must be matched accurately. For example, if the force of the gas spring is too low, the hand force required by the user becomes uncomfortably high and may not hold the application in the open position. The extension force depends directly on the weight of the hood, the center of gravity points, as well as the link points of the gas spring. non-blocking gas springs Dimensions The diameter and the length of the gas spring are determined by its extension force and the required stroke. By varying the mounting orientation, it can be matched optimally to the installation space available. Colour and Material Most gas springs used in automotive applications are unobtrusive black. However, for weight reduction purposes the gas springs can be manufactured in polished aluminum for a high-tech look. End Fittings To ensure optimized and cost-effective mounting, and to take full advantage of the installation space while ensuring the required angle movement, different end fittings can be selected. blocking STABILUS dampers LIFT-O-MAT BLOC-O-LIFT STAB-O-SHOC Small Selection of Available End Fittings Speed Curve and Damping A special characteristic of the gas spring is damping. Damping can be used to determine a specific speed curve, for example for the trunk lid. When and how strongly the damping action should work can be established individually. Speed Dynamic Damping Hydraulic Damping Stroke Additional Possibilities In addition to their force-supplying and damping functions, gas springs can be equipped with additional features. For example, an end position stop protects against accidental closing, and a telescoping tube makes it possible to open the hood to a service position that is beyond the normal opening angle, just to name a few examples.

3 Non-lockable LIFT-O-MAT Gas Springs Dampers and STAB-O-SHOC Lifting, Lowering, Moving, and Adjusting With accurately defined extension force and user-specific damping, the LIFT-O-MAT gas spring provides optimum weight equalization, supports forces, lifts heavy loads, and swings lids and hoods. With its damping characteristics it ensures user-friendly movements. Properties and Advantages Numerous sizes and force variants are available as standard products Linear spring characteristics for even force increase across the entire range of movement Upon request, progressive or decreasing spring characteristics for force supply at the beginning or end of the stroke Available with dynamic or hydraulic damping, depending on the application and installation orientation Different end fitting systems for fast and easy mounting For operating temperatures between -30 C and +80 C Standard Series Program diameter (mm) outside diameter D2 (mm) Extension force (N) connection D2 Piston system with filling medium Oil Special seal and guide system D1 connection Max. stroke (mm) Product Variants End position stop: This mechanical end position stop, which can be located on the outside or inside, provides additional protection against accidental closing of trunk lids Hydro-Lift : In addition to the normal LIFT-O-MAT function, the movement can be stopped in several positions LIFT-O-MAT high friction: Due to increased friction, these gas springs can be stopped in any position Electro-Lift: In addition to the gas spring function, electricity is transmitted or even switched on, for example to illuminate the engine compartment or the trunk. Inter-STOP : By dividing the stroke into different functional ranges, it is possible to manually hold/ stop the application, such as the trunk lid, in several positions. Hydraulic Vibration Damping Dampers are used to influence the properties of movements and vibrations in a positive manner. They are matched to the individual application. Oil hydraulic dampers consist of a pressure cylinder, a piston rod with piston system and end fittings. During a movement, the filling medium the oil is forced through specifically dimensioned bores in the piston, thus creating the desired damping force. Properties and Advantages Compact dimensions with high reliability and a long service life For operating temperatures between -30 C and +80 C Pre-defined linear, progressive, or decreasing damping characteristics for optimized results Position-controlled damping rate; e.g., for steering dampers and driver seat dampers Frequency-controlled damping characteristics Electrically adjustable dampers Different end fittings for easy mounting Locking Gas Springs BLOC-O-LIFT Variable Positioning, Rigid or Spring Locking BLOC-O-LIFT gas springs work according to the same principle as the LIFT-O-MAT gas springs. In addition, the BLOC-O-LIFT gas springs can be locked in any position, and depending on their design springlocked or rigidly in tension or compression direction. The locking function is made possible by a valve that is integrated into the piston; the valve separates the two pressure chambers in a gas leak-proof manner. If it is closed and the gas exchange between the two pressure chambers is interrupted, the BLOC-O-LIFT gas spring is locked. The valve closes automatically as soon as the valve tappet is released from the outside. Properties and Advantages Available with rigid locking in tension and compression direction. Optionally, this function can be achieved regardless of the orientation. Also available with a small actuation range of 1 mm (standard 2.5 mm) for very easy operation. Upon request, these safety applications are available with an override function. Left: BLOC-O-LIFT gas spring with spring locking Right: BLOC-O-LIFT gas spring with rigid locking and separating piston for orientation-independent installation Product Line Dampers are matched to the specific requirements of the application and their design is optimized For orientation-independent or orientation-specific mounting As dampers with and without extension force With damping forces in one direction, or in extension and compression direction Upon request, vibration damping only at certain frequencies (frequency-controlled damping) connection according to product range with filling medium Separating piston Speed and damping regulating valve system Special seal and guide system connection with thread

4 Gas Springs and Dampers in the Automobile Pop-up Headlights Rod System Damping Hood Glove Compartment Center Console, Phone Console Window Adjustment Tailgate Trunk Lid Steering Damping Convertible Top, Convertible Top Adjustment Belt Tensioning Damping Roll Bar Engine Damping Steering Column Adjustment Gullwing Doors Seat Height Adjustment, Backrest Adjustment Seat Adjustment Fold-out Table Backseat Adjustment

5 Gas Springs and Dampers for Utility Vehicles Compact design, high functional comfort and integrated operating safety expand the range of applications for STABILUS products in utility vehicle design. e.g., vehicle bodies... Gas springs and dampers make it easy to open and adjust tailgates, hoods, and covers. e.g., trucks... Gas springs are used for comfortable opening and securing of engine compartment covers, truck cab doors and windows. In the driver seat, they dampen unpleasant jolts due to bumpy roads and thus ensure a pleasant, relaxed, and ergonomic seating experience. e.g., buses... In luggage compartments, gas springs ensure comfortable opening, as well as dampened, safe, and noiseless closing. Because the seats can be adjusted ergonomically, even long journeys are a pleasant experience. Other Applications: Shelf for the driver Shelf for carry-on bags Glove compartment Battery compartment Folding roof Tailgate Front end lid Steering Cover tarp Hood Air deflector Bunk Motor Carburetor control Manual transmission Driver seat Driver s cab Luggage compartment Maintenance compartment Seats Roof light Steering column Radio cover

6 S TA B I L U S A c o m p a ny w i t h a n i n n ovative t ra d i t i o n P r o d u c t c h a ra c t e r i s t i c s, a d va n t a g e s, u s e s Pioneer Per formance I n , S TA B I LUS p r e s e n t e d t h e w o r l d s f i r s t gas spring manufact u r e d in s e r i e s p r o d u c t i o n to t h e s w i vel chair industr y ; in , t h e f i r s t lockable gas spring. To date, m o r e t han 2. 0 billion gas springs have b e e n p r o d u c e d, giving S TA B I LUS t h e longest e x p e r i e n c e w o r l d - w i d e in t h e d e sign and m a n u f a c t u r e of gas springs. W i t h a n annual p r o d u c t i o n of more t han 10 0 million unit s, S TA B I LUS is t o d ay t h e world marke t leader for m u l t i p l e industrial a p p lic a t i o n s. O c c u p a t i o nal health p r a c t i t i o n e r s a n d s w i vel chair manufac t u r e r s a p p r o p r iately consider S TA B I LUS a pioneer in t h e d e velopment and m a n u f a c t u r e of gas springs for e r g o n o mic s e a t i n g in t h e s w i vel c hair area. T h e gas spring make s it p o s sible to adjust height, s e a t and b a c k r e s t tilt of t h e s w i vel chair q u ickly and easil y. Globall y Ac tive W i t h a global s ales and s e r v i c e n e t w o r k and 10 p r o d u c t i o n sites in Europe, USA, M e x i c o, Brazil, N e w Z e aland, Australia and Ko r e a S TA B I LUS supplies and suppor t s m o r e t han 2,4 0 0 customer s world - w i d e. For all business sec tors H aving b e e n successfull y adopted a n d incorporated in t h e automo - t i ve and f u r niture industries for s e veral d e c a d e s, S TA B I LUS gas s p r i n g s have now also b e c o m e an i n d ispensable d e sign element in c o u n t l e s s industrial a p p lic a t i o n s i n t h e most diver s e s e c t o r s. Gas springs and dampers for applic ations in ve hicle e ngineering C o m p a c t d e sign, high level of o p e r a t i n g convenience and s a f e t y i n use continue to e x p a n d t h e f i e l d of a p p lic a t i o n s for S TA B I LUS p r o d u c t s. e.g. M o t o r ve h icles a n d s u p e r s t r u c t u res Gas springs and damper s facilit a t e t h e o p e ning and adjustment of h o o d s, hatches and cover s. e.g. Agricultural ve h icles T h e y dampen unpleasant shock s in t h e d r i ver s s e a t c a u s e d by uneven land resulting in comfor t a b l e, re - la xe d and ergonomic s e a t ing. e.g. B u s e s T h e y allow s e a t s to b e adjusted t o t h e passenger s b o d i e s, s o t hat e ven long journeys b e c o m e a p o si - t i ve e x p e r i e n c e. e.g. R a ilway ve h icles H e r e, too, blocking gas springs in s t e p l e s s adjust a b l e s e a t s ensure e r g o n o mic s e a t i n g. Customer satisfaction Customer ser vice and customer satisfaction are key objectives for the company. STABILUS is known in par ticular for its technical innovation, qualit y and competitive pricing in all its business units. Highest Quality A s the leading gas spring supplier worldwide, our qualit y management system fulfils without question the high qualit y requirements of international standards, such as DIN EN ISO , as well as the new world standard ISO / TS with the regulator y requirements of QS 9000, VDA 6.1, E AQF, and AVSQ. Care for the environment STABILUS places utmost impor tance in achieving environmentally friendly production methods. Its success in this area is documented by the cer tification of its environmental management system in conformit y with DIN EN ISO Service and technical application support STABILUS provides ex tensive technical, design and installation suppor t in specific applications as a mat ter of course. The ex tensive knowhow of our application consultants and technicians coupled with our highly ef ficient installation proposal programmes and prac tical arrangements, also on site, ensure optimal solutions. F o r c e [ F ] Seal and guide element Operating principle Piston B o r e Piston cross- sectional area O perating principle of a g as spring P r e s s u r e t u b e T h e gas spring is a hydropneumatic adjusting element, consisting of a p r e s sure t u b e, a piston rod w i t h piston and a p p r o p r iate con - n e c t i o n f i t t i n g s. It is f illed w i t h c o m p r e s s e d nitrogen, w hich ac t s w i t h e q u al p r e s sure on dif f e r e n t l y d i m e n sioned cross-sect i o nal areas of t h e piston. T his p r o d u c e s a f o r c e in t h e e x t e n sion direct i o n. T his e x t e n sion force c a n b e e x a c t l y d e f i n e d w i t hin p hysic al limit s t h r o u g h t h e a p p r o p r iate s e l e c t i o n of t h e f illing p r e s sure. Spring c harac teristic cur ve a nd F1 force F 3 F 1 C o m p r e s s i o n E x t e n s i o n Spring characteristic curve and F1-force F 4 F 2 St r o ke [ S ] T h e spring charac t e r istic cur ve describes the gas spring progression f o r c e over t h e stroke, i.e. f r o m t h e e x t e n d e d to t h e compressed st a t e a n d vice ver s a. U nlike mechanic al springs, gas s p r i n g s have an e x t r e m e l y f lat, almost linear charac t e r istic cur ve a n d t h e r e f o r e allow a uniform comfor table adjustment or pivoting m ovement. T h e spring rate, X, representing the force ratio F2 / F1, lies b e t w e e n 1. 2 and 1. 4 w i t h s t a n d a r d gas springs. O t h e r values c a n b e d e f i n e d on request and a c c o r d i n g to t h e a p p lic a t i o n. To g e t h e r w i t h t h e dimensions, t h e F1 force is t h e major d e s c r i p t i ve f e a t u r e for t h e choice of a gas s p r i n g and it is t h e r e f o r e specif i e d in all STABILUS brochures. It defines t h e value of t h e spring force and is m e a sured 5mm b e f o r e t h e e n d of t h e e x t e n sion movement. T h e dif f e r e n c e b e t w e e n t h e force lines for t h e compression and e x t e n sion direct i o n, FR, is t h e r e sult of f r ic t i o n ef f e c t s. E x tending speed and d a m ping A signif ic a n t advant a g e of gas s p r i n g s over mechanic al springs is t h e d e f i nable speedcur ve, w hich allows for a damped and comfor t- a b l e adjusting movement. Tw o t y p e s of damping c a n b e d istin - g u ished : H ydraulic d a m p i n g T h e e x t e n d i n g speed is d e t e r mined b oth by t h e arrangement and t h e d iameter of t h e b o r e s in t h e piston and by the viscosity of the oil used. W h e n t h e gas spring is inst alled w i t h t h e piston rod facing d ow n t h e e x t e n d i n g piston f i r s t t r avels t h r o u g h t h e gas-f illed and t h e n t h r o u g h t h e oil -f illed par t of t h e p r e s sure t u b e. A s s o o n as it is i m m e r s e d in t h e oil t h e piston rod m ove s at a considerably lower s p e e d. S p e e d H y d r a u l i c r a n g e P n e u m a t i c r a n g e H y d r a u l i c r a n g e Hydraulic damping D y n a m ic d a m p i n g H e r e t h e b o r e in t h e piston is replaced with a longitudinal groove i n t h e wall of t h e p r e s sure t u b e w hich s e r ve s as a by p a s s. It s geometr y and the length determine t h e damping cur ve. T his technique allows position- independent damping of t h e gas springs. S p e e d Dynamic damping P n e u m a t i c r a n g e St r o ke O i l St r o ke... t e c h n o l o g y g i v e s c o m f o r t

7 C h o i c e a n d a p p l i c a t i o n o f g a s s p r i n g s N o n - b l o c k i n g g a s s p r i n g s L I F T- O - M AT Dimensions according to c hoice STABILUS S TA B I LUS of f e r s an e x t r e m e l y w i d e r a n g e of gas spring t y p e s, w hich var y in respect of t h e i r e x t e r nal d i m e n sions, speed cur ve s and e x t e n sion variant s, and invaria b l y meet t h e most stringent r e q u irement s. A large s e l e c t i o n is i n c luded in t h e S TA B I LUS st a n d a r d produc t range and can be delivered a t shor t notice. Ser v ice life and m aintenance Gas springs are maintenance - f r e e! T h e y are d e signed to specif i c r e q u irement s and o p e r a t e for year s and year s w i t h o u t failure w h e n p r o p e r l y inst a lled. A l s o for p a r t icularly high number s of load a l t e r a t i o n s special s e a ling s y s t e m s a r e available w hich allow e.g. s p e c i f ic gas springs in s w i vel chairs to withstand up to one million load c ycles without damage. Connec tions Dif ferent connections are available d e p e n d i n g on t h e a p p lic a t i o n. S TA B I LUS t h e r e f o r e of f e r s a w i d e r a n g e of plastic or met a l hinge e ye s, including t h e easy-to - m o u n t a n g l e joint t hat only has to b e f i t t e d on t h e ball s o c ke t and a llows for t w ist-f r e e inst a llation. without locking Gas Springs with locking LIFT-O-MAT BLOC-O-LIFT STAB-O-MAT STAB-O-BLOC I n st allation instruc tions Tw i s t-f ree c o n n e c t ion F o r ma x imum s e r v ice life, gas s p r i n g s should not b e e x p o s e d to t w ist s or lateral forces. Suit a b l e c o n n e c t i o n f i t t i n g s, e.g. angle j o i n t s, c a n b e used for t h e t w istf r e e connect i o n of t h e gas springs. I n s t a llation p o sition Gas springs except those designed f o r p o sition-independent inst alla - t i o n are p r e f e r a b l y installed with the piston rod facing d ow n s o as to maximise the hydraulic damping e f f e c t and to ensure o p t i mal lubric a t i o n of t h e g u i d e and s e al s y s t e m. Dampers STAB-O-SHOC Power Tailgate Systems POWERISE Automotive Te m p e rature b e h av iour T h e temperature of t h e gaseous nitrogen inside t h e gas spring i n f luences it s e x t e n sion b e haviour w i t hin cer t ain limit s. T h e st a n d a r d t e m p e r a t u r e range lies b e t w e e n -3 0 C und C. In addition, g a s springs w i t h special s e aling s y s t e m s for e x t r e m e loads are available. O p e rational s a fet y T h e o p e r a t i o nal s a f e t y of t h e gas s p r i n g is p r i maril y achieve d by s e als d e signed to ke e p t h e gas pressure inside. For your protection, no bending loads should be exer ted o n t h e gas springs. Damage c a u s e d by subsequent mechanical operations, i n c luding welding, p e r f o r m e d on the gas springs, as well as contamination or painting of t h e piston r o d may lead to t h e failure of t h e d e v ices. Lif ting, lowering, mov ing a nd adjusting W i t h t h e i r accurately adjusted e x t e n sion force and a p p lic a t i o n - s p e c i f ic damping L I F T- O - M AT g a s springs of f e r o p t i m u m weight c o m p e n s a t i o n, force suppor t, t h e y o p e n and close f laps and b o n n e t s a n d ensure user-f r i e n d l y movement s e q u e n c e s t hank s to t h e i r damping c harac t e r istic. Charac teristic s and benefit s E Available in a variet y of st a n - d a r d size s and force variant s E L i n e a r spring cur ve for uniform f o r c e p r o g r e s sion over t h e e n t i r e spring t r avel E Available w i t h p r o g r e s sive or d e g r e s sive spring cur ve for f o r c e suppor t at stroke st a r t or e n d p o sition E Available w i t h d y namic or hydraulic damping according to a p p lic a t i o n and f i t t i n g p o sition E Va r i o u s connect i o n s y s t e m s for p r a c t ic al and s w i f t inst allation St a n d a r d S e r i e s P r o g r a m P iston rod d iameter D1 ( m m ) P r e s s u r e t u b e c o n n e c t i o n D2 Piston system P r e s s u r e t u b e w i t h filling medium O i l Special seal and guide system D 1 c o n n e c t i o n P r e s sure t u b e o u t side diameter D2 ( m m ) Produc t variants E H ydro - L i f t : In addition to t h e L I F T- O - M AT f u n c t i o n, t h e s e g a s springs c a n b e p o sitioned at a ny d e sired p o int E L I F T- O - M AT h i g h f ric t ion : T h e increased f r ic t i o n of t h e s e g a s springs allows for stepless p o sitioning E Elec t r o - L i f t : In addition to t h e gas spring f unc tion, an elec t r ic c u r r e n t is t r a n smit t e d or even s w i t c h e d, e.g. for illuminating t h e engine compar t m e n t or b o ot s p a c e E I n ter-st o p : T h e stroke is d i v i d e d into a number of f u n c- t i o nal areas to allow manual p o sitioning of t h e a p p lic a t i o n, e.g. a f lap E x t e n sion force M a x. stroke ( N ) ( m m ) Small selection of available connections t e c h n o l o g y g i v e s c o m f o r t

8 B l o c k i n g g a s s p r i n g s B L O C - O - L I F T D a m p e r s a n d S TA B - O - S H O C H ydraulic dampening of v ibrations Variable positioning, rigid or spring blocking B LO C- O - L I F T gas springs raise l o a d s w i t h an accurately t u n e d e x t e n sion force and a p p lic a t i o n - s p e c i f ic dampening w hile ensuring u s e r-f r i e n d l y movement s e q u e n - c e s. In addition, BLO C- O - L I F T g a s springs c a n b e blocke d in a ny p o sition, w i t h springing or r i g i d blocking in t h e e x t e n sion or c o m p r e s sion direct i o n d e p e n d i n g o n t h e d e sign. Va r ia b l e blocking is m a d e p o s sible by integrating t h e valve into t h e piston, w hich s e p a r a t e s b oth p r e s sure chamber s g a s t i g h t. W h e n t h e valve is clo - s e d, t h e r e b y interrupting t h e gas e xc hange b e t w e e n b o t h p r e s sure c hamber s, t h e BLO C- O - L I F T gas s p r i n g is blocke d. T h e valve closes a u t o matic all y w h e n t h e valve t a p - p e t is released e x t e r nall y. T h e springing blocking variant is i d e al for t h e smooth dampening o f e.g. shock s, impac t s or pulse - t y p e p e a k loads ( e.g. in s e a t s and o f f ice s w i vel chair s ). L e f t : S p r i n g b l o c k i n g B L O C- O - L I F T g a s s p r i n g R i g h t : R i g i d b l o c k i n g B L O C- O - L I F T g a s spring with separating piston for positionindependent installation St a n d a r d S e r i e s P r o g r a m P iston rod d iameter D1 ( m m ) connection according to product range with filling medium S e p a r a t i n g p i s t o n D2 Speed and damping r e g u l a t i n g v a l v e s y s t e m Special seal and guide system D 1 connection with t h r e a d P r e s sure t u b e o u t side diameter D2 ( m m ) Charac teristic s and benefit s E R i g i d or spring blocking in t h e e x t e n sion or compression direct i o n. O p t i o nall y, a p o sitioni n d e p e n d e n t variant is available E A l s o available w i t h shor t re - l e a s e t r avel of only 1 mm ( n o r- mall y 2. 5 mm ) for e x t r e m e l y light o p e r a t i o n E Continuous release is also available on request ( e.g. for r o c k i n g t h e backrest of s w i vel c hair s ) E x t e n sion force ( N ) M a x. stroke ( m m ) D a m p e r s are needed to p o sitively i n f luence t h e nature of movement s a n d vibrations. T h e y are d e signed t o match t h e par t icular a p p lic a - t i o n. O il - hydraulic damper s consist of a p r e s sure t u b e, a piston rod w i t h piston s y s t e m and a piston r o d connect i o n f i t t i n g. T h e mo - vement of t h e piston p r e s s e s t h e f illing medium ( o il ) t h r o u g h suit a b l y dimensioned b o r e s into t h e p iston, t h u s p r o d u c i n g t h e d e sired d a m p ing force. Charac teristics and benefits E Compac t dimensions w i t h ma x i - m u m relia b ilit y and d u r a b ilit y E Suited for o p e r a t i n g tempera - t u r e s b e t w e e n C and C C alculating t he inst allation of a gas spring T h e S TA B I LUS inst allation d e sign p r o p o s al s of t ware s e l e c t s and d e signs t h e o p t i mal gas spring for a specif ic a p p lic a t i o n. F o r t his, t h e f o llowing a p p lic a t i o n d e t ails, e.g. a f lap, are needed : E d i m e n sions and weight E o p e ning angle to b e achieve d E a t t a c h m e n t p o i n t s for t h e gas s p r i n g s From t his dat a t h e following is d e r i ve d : E t h e stroke A [ m m ] E t h e e x t e n d e d length B [ m m ] E t h e e x t e n sion force F 1 [ N ] E a n d t h e t y p e of connect i o n E D e f i n e d linear, p r o g r e s sive or d e g r e s sive damping force c harac t e r istic for o p t i mal r e sult s E Va r ia b l e damping rate e.g. for s t e e r ing damper s and d r i ver s e a t damper s E Electric all y adjust a b l e damper s E S e veral connect i o n variant s for e a s y inst allation Produc t variants E V i b r a t i o n dampening only at specif ic f r e q uencies ( f r e q uenc y - d e p e n d e n t dampening ) u p o n r e q u e s t E D a m p e r s are d e signed to o p t i mall y match t h e par t icular a p p lic a t i o n E F o r p o sition-d e p e n d e n t or p o sitionindependent inst allation E D a m p e r s w i t h or w i t h o u t e x t e n sion force E W i t h damping forces in one d i r e c t i o n or in t h e e x t e n sion a n d compression direct i o n I n s t r u c t i o n s f o r t h e d e s i g n o f g a s s p r i n g s I n a subsequent step, t h e d e sired e x t e n sion and damping charac t e r i - s t ic c a n b e d e t e r mined. To make your ow n rough e s t i mate a n d to s e l e c t t h e a p p r o p r iate gas s p r i n g f r o m our st a n d a r d p r o d u c t r a n g e, you c a n use t h e following a p p r ox imation formula and a p p li - c a t i o n ske t c h. A B±2 b L P D G Determining t he e x tension force F1 [ N ] at 20 C F1 = G x D x 13 [ N ] bx n G = w e i g h t of f lap in kg L = d ist a n c e f r o m centre of g r avit y to pivot p o i n t in mm. b = e f f e c t i ve lever arm of gas s p r i n g in mm, f lap o p e n. 13 = c o nver sion fac t o r kg - N + s a f e t y margin P = f lap at t a c h m e n t ( suggest a p p r ox. 2 / 3 L ) n = n u m b e r of gas springs ( s t a n d a r d : n = 2 ) D = e f f e c t i ve leverarm of g r avit y i n mm, f lap o p e n Find out more about replacement trunks, tailgates & components we have.