FR2461849A1 - HELICOIDAL SPRING DEVICE - Google Patents

Abstract

SHAPING OF ELASTIC ELEMENTS. THE SPRING SETS SCREWED INTO EACH OTHER APPLY, ONE AGAINST ANOTHER IN THE AREA OF INTERNAL AND EXTERIOR DIAMETERS AND IN A HELICOIDAL APPLICATION AREA. HELICOIDAL SPRING REPLACING THE BELLEVILLE WASHERS.

Description

? 461,849

  The present invention relates to a device for

  coil springs having two coaxially arranged springs

  and each having section turns of determined geometry. Devices of this type are known, for example, from Lueger's Lexicon of the Technique: Foundations of Machine Construction, Vol 1, 1960, page 482, left column. 'assemble springs to

  disc, called "Belleville washers", to form pa-

Quets.

  The object of the present invention is to provide

  helicoidal springs, whose turns are the most

  wind a circular section, the shape that is typical for Belleville washers. A set of springs thus obtained is then

screwed in another game.

  The device obtained in this way then has the following properties: 1. Unlike the usual Belleville washer sets, it is no longer necessary to provide elements of

  Suidage neither externally nor internally. The economy of the

  The guiding element also helps to avoid adverse effects.

  rables caused by the friction occurring between the spring

  and the guide element. It is obvious that a guideline

  ge is necessary when a spring is working at the limit of buckling,

  2. The elastic device can absorb not only

  purely axial but also light movements

lateral deviations.

  3. Unlike the Belleville washer sets, the device according to the invention can also be used in cases where the movements are not linear because this coil spring device also allows accordion-like movements. Belleville washers and Belleville washers are degressive and strongly curved. In the device according to the invention, the

  characteristic is, however, substantially linear and does not

  respond to the characteristic of Belleville washers that in the state

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strongly compressed.

  5. the spring sets can be characterized

  relatively flexible elastic tick without the turns becoming

  completely fade and then reverse as may be

  with Belleville washers because of the

  ritic strongly degressive of the latter.

  6. It is also possible to make the games of

  springs of synthetic material in fact that this material pre-

feels a weak elastic modulus.

  7. As a result the manufacturer of springs can pre-mount a column thus avoiding the assembly and assembly, by the user, washer by washer, on a

  element or guiding sheath.

  8. The ends of the column may be provided with fasteners which allows the column to be used as a tension spring which is unusual for

Belleville washers.

  The new device according to the invention is

  characterized in that: a) the inner diameter and the outer diameter are substantially parallel, b) the sets of springs screwed into each other,

  apply against each other in the area of

  meters inside and outside and in a helical application zone, c) the cross section of the turns corresponds to that of a Belleville washer and the bending is also identical to that of a Belleville washer, the turns of one of the games of springs being bent in one direction and the turns

  the other set of springs in the opposite direction.

  Belleville washers are obtained by stamping

  wise from roll of strip which results in a loss of material up to 50%. The fibers of

  rolled strip always extend in the longitudinal direction

  dinal, this is why the fibers of the Belleville washers pre-

  feel directions six and twelve o'clock. As a result, Belleville washers break more easily in these areas.

  only at three and nine o'clock directions.

  According to one characteristic of the invention, the turns are obtained by winding a flat material. This process makes it possible to save about 50% of the material and the extent of the fibers is always perpendicular to the direction of rupture. that is, parallel to the direction of bending stress. There is also no more cutting, which

  removes the shock points in the structure that are inevitably

  tables during stamping and cutting. In others it is not

  necessary to make corrections in order to eliminate

  the deteriorated structure of the metal, essential operations

  to obtain Belleville washers of good quality.

  According to another characteristic of the invention, the sets of springs are screwed into each other under an initial tension. This results in an elongation of the spring,

  lengthening which increases proportionally to the initial tension.

  When the spring device is extended by X mm, this cor-

  responds to an elastic force of y kg. This means that the spring sets are in their relaxed state only under

  a load of y kg. When soliciting games of res-

  spells, we gain this strength which also allows us to calculate

  the springs for a weaker force. In the case where

  the amplitude of deformation produced by this force, it is advantageous to choose an initial tension corresponding to the

half of this amplitude.

  These features prevent springs

to unscrew during transport.

  According to another characteristic of the invention, each of the sets of springs is divided into two individual games which

  are in contact with each other along the

  a spire. thus obtaining a device having a

significant depreciation.

  The embodiment of the device using the same material as that usually used, for the manufacture

  of Belleville washers, allows you to find

  known characteristics of the latter.

  When making the devices according to the invention

  made of a synthetic material, a spring of new type is obtained.

veal.

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  According to a last characteristic of the invention, the flat material already has the shape of the contact or application zones. As a result, the places of contact can

  already, before winding up, be made to present the

  application, for example a cyclo form or the like. This shape can be obtained, for example, by rolling, which creates an advantageous hardening of the material in the application zone.

  Various other features of the present invention

  come out from the following detailed description.

  Embodiments of the object of the invention

  are given as non-limiting examples,

annexed.

  Fig. 1 is a perspective, partially in section,

a set of individual springs.

  Fig. 2 is a perspective, partially in section,

  two sets of springs screwed into each other.

  Fig. 3 is a top view of FIG. 2 along arrow A. FIG. 4 shows a cross section of a spiral with a rectangular section, FIG. 5 is a cross-section of a turn to

trapezoidal section.

  Fig. 6 shows in cross section a turn of which

  the section widens cone outwards.

  Fig. 7 is a cross-section of a turn of which

  the section widens cone inwards.

  Fig. 8 shows, in cross section, a turn whose outer zones have a semicircular shape

  but whose surfaces are parallel.

  Fig. 9 is a cross section of a turn of which

  the areas of application are in the form of a quarter of

  key. Fig. 10 represents, in the form of diagrams, there force relative to the elastic race of a Belleville washer

  as well as a device according to the invention.

  Fig. 11 shows, in cross-section, a subdivided coil.

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  Fig. 12 is a section similar to that of FIG. 9

  but the zones of application of the turn are plains.

  The first set of springs 11 comprises turns 12 whose section 13 is rectangular. The width is 25 mm (scale 1 1), while the thickness is 3 mm. As a result, the ratio is about 8: 1. The inside diameter is 52 mm and the outside diameter is 102 mm. In the unloaded state, the spring set has a length L0 of about

  mm. The material is the same as that used for the manufacture

  Belleville washers and the treatment of the material is also identical. As the figure shows, each of the

  turns has the appearance of a Belleville washer, which is

  radially and bent so that one edge of the cut is maintained at about six o'clock and the other edge of the cut is pushed down slightly (also at six o'clock), this "pushing towards the bottom "determining the pitch. This

  spire is followed by another which is also a

  Belleville and forming a single piece with the first turn. It is obvious that the game of springs-is not manufactured this way. for example, we leave a full room, and we

  firstly coaxially with respect to the long geometric axis

  gitunal 14, a hole that corresponds to the inside diameter. Di and then we practice with a tool a radial dive under

  an angle So. The width of the dive, that is to say, the quantity

  removed piece of material determines the thickness of a turn 12.

  It is also possible to wind the turns 12 to hot while creating the step at the same time. In this case, it is first necessary to bend the plane flat material in order to obtain then,

  for the finished spring set, the typical inclination of the spindles

  res. In fig. 2, the set of springs it is assembled with

  a set of springs 16 which is of identical design. This-

  during the set of springs 16 is rotated by 1800 about the longitudinal axis 14 with respect to the set of springs 11 and is then screwed into the latter, either from above or from

  the bottom. It is obvious that an assembly of springs games

  ticks is only possible when the screw thus created presents

  the shape of a cylinder of circular diameter.

  In the case where the coil spring tapers conically upwards or downwards, it is necessary to manufacture different sets of springs whose section of one has an inclination in one direction while the inclination of the section

  the other game has an opposite meaning.

  This example shows that the coil spring can also

  different form from that illustrated by the

  drawings: it can be cut in the middle zone, it can present

  a conical but defined form, etc.

  When making a set of springs by means of a chip removal process, the section can also be modified by making more or less wide dives. It is, for example, possible to provide in the upper part of the coil spring weaker sections in the lower part. Likewise, it can be provided, for example, exclusively

  in the middle part, weaker sections. These changes

  sections can be calculated to answer cases

  specific use of the spring.

  In addition, it is also possible to

  coidal whose inner diameter is not constant and is, for example,

  example, located on the generators of a c8ne. The diameter

  can also have a biconical shape, the smallest

  diameter can be halfway up the spring.

  These same embodiments can also be obtained when the turns are made by bending. In this case, it is necessary to cut the flat material so that it has the appropriate width and thickness, these two

  criteria depending on the characteristics of the spring to be

  ser. The sector 17 cone-shaped shown in FIG. 3 has the usual rectified surface for helical springs.

  Assuming that fig. 4 represents the transcut section

  versale of the set of springs 16 of FIG. 2, there are two application areas 18, 19. These zones are located on a turn by which the set of springs 16 is based on the set of

  11. Consequently, the cutting surfaces are practically

  in contact. This contact also remains when the

24 6 18 49

  assembled coil spring is ground internally and ex-

  later so that the outer surface and the surface

  inside the helical spring form cylinders with

circle.

  In this way, it would have been possible to obtain the cross section of FIG. 5 o the areas of application

  21, 22 form sharper edges than in fig. 4.

  Fig. 6 shows that the section can also increase

  outward like a corner.

  In the embodiment shown in FIG. 7, the

  It increases like a wedge inwards.

  The application zones 23, 24 of the embodiment example

  represented in FIG. 8 constitute part of a semi-rounded

  circular. In this case, there is no longer contact

  songs but a superficial contact. The semi-circular shape has been chosen as an example but it is also possible

  to use other conical sections such as elliptical sections

ticks or parabolic dishes.

  In the embodiment shown in FIG. 9 the

  has been rectified only in areas of application 26, 27,

  where the turns must have a characteristic

  developing, the remaining contour not being rectified.

  Depending on each specific use case, it is decided whether the coil spring should work under some friction or not. Examples of achievements show

that this choice is possible.

  It is also possible to produce helical springs of which

  friction or friction increases depending on their

  pressure, the opposite is also possible.

  In addition, Figs. 4 to 9 that matter

  plate used for coiled coil springs

  can already present the section illustrated by these drawings.

  In the diagram of fig. 10 the abscissa represents the court

  elastic in mm and the ordinate the elastic force F in kg.

  The broken line is the characteristic of a colon

  does not consist of a Belleville washer assembly

  in the same material as the coil spring according to FIG. 2. In both cases, the material is 50 Gold V 4. The coil spring has a length of 75.5 mm and the package of Belleville washers a length of 69.6 mm. The cross section of the various Belleville washers corresponds to

  about the turns of the coil spring. This is also

  also valid with regard to outside diameters and

térieur-.

  The dashed line represents only the

  the package of Belleville washers to compression, the

  extension behavior not shown.

  The curves in full line are those of a prototype

  according to the invention. we can recognize that the helical spring-

  dal according to the invention has a substantially linear behavior in a wide area. The surface between the characteristic

  compression and expansion represent the losses.

  Compared to a package of Belleville washers these losses are important, however, one must take into account that the chart

  refers to a prototype while that of the rondel-

  the Belleville is a perfect realization.

  In this regard, it should be noted that a large area of hys-

  however, it is often desirable for some cases of

lisation.

  Fig. it shows how it is possible to further increase these hysteresis losses by dividing the section into two partial sections 28, 29. This result is obtained by realizing a set of springs constituted by an assembly of two

  partial games. In this case, an important friction

along the surface 31.

  - According to fig. 12, the application zones 32, 53 are constituted by surfaces which are perpendicular to the longitudinal axis of the spring when the latter is in the idle state. These plane and perpendicular surfaces to the longitudinal axis have the advantage that they make it possible to

  accurately determine the spiral tilt line

  turn of which tilts the surfaces during the weakest compression of the spring. Thus, the calculations are facilitated

  compared to those needed to determine the characteristics of

  of a jurisdiction with, for example, areas of

  in which the line of contact moves in

function of the compression.

Claims (6)

  1 - coil spring device comprising   two coaxially arranged springs, the coils of which   substantially the same inside and outside diameters   characterized in that the cross-section of a coil (12) corresponds to that of a Belleville washer, the turns (12) of one of the springs (11) being bent in one direction and the turns ( 12) of the other set of springs (16) in the opposite direction and that the turns (12) of the two sets of springs (11, 16) screwed into one another apply, one on the others, following a helical line in the zones of the outside diameter and the inner diameter (Di).   2 - Device according to claim 1, characterized   characterized in that the turns are obtained by winding a flat material.   3 - Device according to claim 1, characterized   characterized in that the sets of springs are screwed together   in the others under an initial tension.   4 - Device according to claim 1, characterized   in that each of the sets of springs is divided into two individual games that are in contact with each other   the other along the width of a turn.   - Device according to claim 1, characterized in that the spring is made in the same   material as Belleville washers.   6 - Device according to claim 1, characterized   characterized in that the spring is made of synthetic material.   7 - Device according to claim 2, characterized   characterized in that the flat material already has the shape   areas of contact or application.