EP0836576B1 - Spring-effect hinge arrangement, for example for one-piece injected plastic closures - Google Patents

Description

The present invention relates to a hinge according to the preamble of Claim 1.

Various resilient hinges, such as those used in particular in one-piece injection molded plastic closures, are known from the prior art. A so-called snap effect should be brought about regularly with such hinges for plastic closures . A snap effect is understood to mean opening the hinge automatically after a certain forced initial deflection (dead center) of the hinge system and an analogous effect when closing, in that the hinge automatically returns to a closed position after a dead center has been exceeded. This effect is basically taken over by special spring elements. In connection with such snap effects , the snap force and the angle of action are characteristic quantities. The snap force is the resistance that the hinge system has to opening and closing. The angle of action is defined by the area which the hinge parts independently overcome due to the spring action and is thus determined by the area between the rest positions of the hinge parts.

The basic principle with the vast majority of such hinges is to pivot a cover part around a defined main movement axis.

European patent EP 0 056 469 describes a hinge for one Plastic closure, the axis of rotation of which is defined by a lid and a main film hinge connecting the closure body is formed and is clearly determined. The snap effect is achieved by interacting with the side this main hinge arranged spring arms reached. The snap effect in one embodiment is based on the bending of U-shaped intermediate elements in other embodiments on a bend of wall areas of the closure parts, with the closure lid usually a Bend in the middle area experiences. The snap effect also comes through here Bending effects around the narrow side.

Those known from the patent specifications WO 92/13775 or EP 0 331 940 Hinge assemblies use primary bending effects in combination with a main axis to achieve a spring effect for a snap effect. The corresponding closures open because of the existing geometric Main axes essentially on a circular path. Both certain constructions protrude when the closure is closed out of the outer contour of the closure.

US Patent No. 5,148,912 describes a hinge assembly for one Closure with closure body and lid, in which the closure is the same has a circular cross section like the closure body itself. Lid and closure body are via two flexible, belt-like connecting arms that are trapezoidal, connected. These connecting arms are flexible executed and over thin points on the closure and on the closure body attached. The hinge-side film hinges of the thin areas are arranged at an angle to each other. Looking at the closure in a view from behind, these hinges are inevitably random arranged in the form of a V open at the bottom. The arrangement of the two The film hinges on the cover side are mirror-symmetrical. That hinge does not have a good snap effect because no suitable spring forces are built up can be.

The known hinge arrangements have various disadvantages. At all known hinges with a main axis, against which straps or similar elements are arranged offset (joint axis offset), there is a need to use this major axis with convex injection molded closures to be arranged outside the closure outer contours. Above However, elements are undesirable for technical and aesthetic reasons. Another disadvantage is that the snap effect due to the difficult mechanical influences is unpredictable and regular inadequate snap effect or inadmissible material stress leads. Another disadvantage is the fact that conventional Hinge arrangements only have unpredictable and insufficient angles of action enable that are often only around 100 °. It is with the known Principles because of the unpredictable mode of action disadvantageous that with a new closure geometry desired for design reasons elaborate prototype series have to be made in order to to achieve technically satisfactory closure kinematics. That with conventional Closures existing main hinge requires that the closure parts must be very close to each other when sprayed. The corresponding Injection mold therefore has the disadvantage that the wall thickness in this area, due to the inevitable connection between the closure bodies, have to be very thin. The subsequent ones Cooling and wear problems have a negative effect on the cycle time and the service life of the injection mold.

Another limitation of such known hinge assemblies, which can be injection molded in one piece from plastic, is that only systems can be achieved with a maximum of one snap effect. In other words are beyond the maximum of one for the opening process of the closure Dead center reached a maximum of two rest positions. These rest positions are essentially the open and the closed state of the closure. Because of that Regularly occurring plastic deformations drop the open resting position not together with the position in the injection molding state.

The mechanical effects associated with the functioning of such closures The main reasons are spiral spring effects. The energy that needs is used to deform a bending element by means of bending Snap force of the hinge. If an element becomes a relevant one for this effect The corresponding bending deformations are exposed to bending Elements large compared to their characteristic sizes (e.g. thickness a bending plate) or the bending springs have one in the unloaded state considerable spatial expansion. With very small closures or with special ones Closure geometries (small radii of curvature in the area of the Hinge), the required functional elements can be more conventional Hinge arrangements, such as the main hinge and tensioning straps, no longer realize or lead to insufficient snap effects or inadmissible Material stress. Another limitation is that the Closures in the area of the hinge necessarily have a convex outer contour must have.

If you observe the with different existing plastic closures Power flow, so there are considerable variations with the same closure types firmly. Thin areas (film hinges) are not permitted in many constructions highly stressed. Is a fastener a fixed main axis of movement Given in the form of a thin spot, there are sometimes large constraints recognizable in the functionally important elements, especially in the film areas. Hinge parts that, for example, fix together with a main film hinge connected, still form a relative in the open state rigid unit. The closure becomes a relative movement when the hinge is open forced against the main container along the main hinge, can through this rigid connection between the lid and the main container high tensions in the functionally important hinge elements which lead to the destruction of the closure.

The path that the hinge parts relative to each other when opening or closing describe is essentially with all these conventional hinge principles a circular path that is precisely specified by the main film hinge becomes. Are requirements for the relative movement of the hinge parts when opened, these can not be covered by such constructions become.

Many materials (including sprayable plastics) show unfavorable behavior, if they are exposed to stress for a long time. This Creep and aging effects have a negative impact on the functioning of a Closure. It is therefore disadvantageous that the known Hinge arrangements do not take this into account and in the Rest positions often have considerable residual stresses.

It is therefore an object of the present invention to provide a hinge which with largely predictable, good snap forces and large possible angles of action, if desired also over 180 °, below Avoiding excessive material loads a defined but variable Relative movement of the closure parts to one another about a virtual movement axis and allows several stable resting positions if desired. It is also Object of the invention to provide a hinge, which is also small and complicated, especially concave closure geometries, can be used and largely within the outer contour of the closure can be arranged. In particular, the optimal design of the injection mold be possible, on the one hand, to shorten the cycle time during production and on the other hand to increase the service life of the injection mold.

This object is achieved by the invention specified in the claims solved.

For example, a certain mutual movement curve of the hinge parts an advantage if an obstacle area has to be overcome. The path of movement also has meaning when the two Hinge parts contain functionally interacting elements. In the area With plastic closures, for example, it is essential that the pouring spout meet with their sealing counterpart at a favorable angle to achieve an optimal seal.

The invention enables a hinge system which has two or more essentially tension-free rest positions and intermediate dead points during the opening and closing process. The states beyond the dead centers are predetermined and controlled. You can achieve several snap effects with different snap forces in one opening and closing process, based on the constructive concentration of functional hinge elements for the targeted use of quasi-stable conditions. The functional, mechanical effects are no longer bending effects around the narrow side, but coordinated pulling and pushing effects with their possible secondary appearances. If functionally important elements of the present invention are subjected to bending, this is only secondary. Such bending deformations are basically prevented as far as possible by appropriate technical measures (e.g. rigid design of the pressure element concerned).

The hinge type according to the invention is further characterized by this from that z. B. with injected one-piece plastic closures no annoying Project parts out of the locking contour.

The idea of the invention aims to provide the necessary functional elements shape and focus that one essentially predeterminable Kinematics of the closure is achieved while ensuring is that the end positions and the intermediate resting positions of the closure largely are tension-free.

The snap effect and in particular the snap force are according to the invention exclusively through the concentrated, between the hinge parts lying, functional elements. Lid and closure body of one Plastic closure can thus with freely definable stiffness and with largely of any geometry.

Since the hinge parts are not firmly connected to one another via a main hinge in the main axis of movement, it is achieved that unintentional relative movements of the hinge parts, for example torsions transverse to the pivoting movement, do not damage the hinge. The invention has no fixed main movement axis. At any point in the movement process, only a momentary, non-fixed swivel axis can be determined, which can also be skewed at times. This virtual axis, which moves during the movement process, is not physically present and does not coincide with a structural part of the hinge. Nevertheless, the cover parts move on the intended path and reliably reach the end position intended for them. The position and movement of this virtual axis and thus the relative movement of the hinge parts are significantly influenced and controlled via the geometric structure of the hinge mechanism. More degrees of freedom are made possible and a total angle of effect of more than 180 ° with - if desired - several snap effects can be achieved. Special embodiments also allow an at least approximately complete integration of the functional elements into the outer contour of the closure, in particular in the case of plastic closures injection molded in one piece.

Figur 1

zeigt einen funktionalen, schematischen Aufbau einer Kippstufe 1 mit zwei Zwischengliedern 20, 21, zwei Druckelementen 2.1, 2.2, zwei Zugelementen 3.1, 3.2 sowie zwei Schubelementen 4.1 und 4.2;

Figur 2

zeigt ein Ausführungsbeispiel einer Kippstufe 1 in geschlossenem Zustand;

Figur 3

zeigt das Ausführungsbeispiel von Figur 2 im offenen Zustand;

Figur 4

zeigt schematisch die Bewegungskurve und drei Kippzustände eines Scharniers 25.1-25.3 mit zwei hintereinander geschalteten Kippstufen;

Figur 5

zeigt ein Anwendungsbeispiel einer Kippstufe gemäß Figuren 2 und 3 in einem einteilig gespritzten Kunststoffverschluß 25 bei geschlossenem Verschluß;

Figur 6

zeigt den Kunststoffverschluß gemäß Figur 5 in offenem Zustand;

Figur 7

zeigt eine Kippstufe 1 mit zwei über eine Dünnstelle 11 verbundenen Druckelementen 2.1, 2.2 in geschlossenem Zustand;

Figur 8

zeigt schematisch die Wirkungsweise eines besonderen Ausführungsbeispiels mit einem Gesamtwirkungswinkel von 180°;

Figur 9

zeigt schematisch ein Verbindungselement 5 mit dargestelltem Zwängungswinkel k;

Figur 10

zeigt eine schematische Darstellung eines Kippvorganges mit seinen Winkelzusammenhängen;

Figur 11

zeigt ein Diagramm zur erfindungsgemäßen Optimierung der Geometrien;

Figur 12

zeigt ein Ausführungsbeispiel mit zwei hintereinander geschalteten Kippstufen 1.1, 1.2 in geschlossenem Zustand;

Figur 13

zeigt das Beispiel von Figur 12 in einem teiloffenen Zustand bei geöffneter, erster Kippstufe 1.1;

Figur 14

zeigt das Beispiel gemäß Figur 12 und Figur 13 im vollständig offenen Zustand mit geöffneten Kippstufen 1.1, 1.2.

The functional principle and exemplary embodiments of the invention are explained in more detail with reference to the figures and diagrams listed below.

Figure 1

shows a functional, schematic structure of a tilting stage 1 with two intermediate members 20, 21, two pressure elements 2.1, 2.2, two tension elements 3.1, 3.2 and two thrust elements 4.1 and 4.2;

Figure 2

shows an embodiment of a flip-flop 1 in the closed state;

Figure 3

shows the embodiment of Figure 2 in the open state;

Figure 4

shows schematically the movement curve and three tilting states of a hinge 25.1-25.3 with two tilting stages connected in series;

Figure 5

shows an application example of a flip-flop according to Figures 2 and 3 in a one-piece injection molded plastic closure 25 with the closure closed;

Figure 6

shows the plastic closure according to Figure 5 in the open state;

Figure 7

shows a flip-flop 1 with two pressure elements 2.1, 2.2 connected via a thin point 11 in the closed state;

Figure 8

shows schematically the operation of a particular embodiment with a total angle of effect of 180 °;

Figure 9

shows schematically a connecting element 5 with a shown angle of constraint k;

Figure 10

shows a schematic representation of a tilting process with its angular relationships;

Figure 11

shows a diagram for optimizing the geometries according to the invention;

Figure 12

shows an embodiment with two flip-flops 1.1, 1.2 connected in series in the closed state;

Figure 13

shows the example of Figure 12 in a partially open state with the first flip-flop 1.1 open;

Figure 14

shows the example of Figure 12 and Figure 13 in the fully open state with the flip-flops 1.1, 1.2.

The invention is explained in more detail below on the basis of examples of one-piece sprayable plastic snap closures. However, the invention is not limited to such plastic parts. The hinge according to the invention, which connects at least two hinge parts in an articulated manner, consists of one or more tilting stages which are each bordered by rigid intermediate members or the hinge parts themselves. A single tilting step has the purpose of giving the hinge a certain partial snap force and partial angle (based on the total opening / closing movement) and is responsible for a snap effect. If several tilt levels are connected in series, the hinge receives the same number of snap effects as tilt levels. When opening or closing, the hinge passes as many dead points as there are tilting stages connected in series. Each flip-flop thus carries a certain proportion of the total angle of effect. The corresponding partial angle can assume a certain desired size through a corresponding geometric arrangement of the functionally important elements of a tilting step. A relationship between the partial angle of a tilting step and the geometric arrangement exists and is used in a targeted manner.

Figure 1 shows a schematic representation of the functional elements of a Tilt level 1 when closed. The flip-flop contains two pressure elements 2.1, 2.2, which are articulated, for example via film hinges, with two intermediate links 20, 21 are connected. Two tension elements 3.1 and 3.2 are parallel to arranged these pressure elements. Between the pressure elements 2.1, 2.2 and the two tension elements 3.1, 3.2 are two thrust elements 4.1 and 4.2 arranged. The flip-flop thus has two functional groups, namely two Connecting elements 5.1, 5.2, which in turn each have a pressure element 2, a tension element 3 and a thrust element 4 included. The functional elements are articulated to the rigid links 20 and 21. This With plastic injection molded lids, flexibility can be achieved with the help of thin points or similar arrangements. The intermediate links 20 and 21 limit the flip level 1 here or the flip level is directly with here Hinge parts not shown directly connected.

To go from the closed to the open state of a flip-flop 1, the rigid intermediate members 20, 21 must be moved against each other that the intermediate member 20 about a current axis of rotation, which here approximately parallel to the line connecting the centers of the two pressure elements lies and is not stationary during the closing process, to the rear emotional. The force that has to be applied describes the Snap force of the tilting step 1. Such a force naturally occurs when opening of the hinge containing the tilting step. The force required changes until the dead center of the flip-flop is reached. If this force increases, The tensions in the functionally important elements also increase. The tension elements 3.1, 3.2 are more and more on tension and the pressure elements 2.1, 2.2 more and more under pressure. Are these burdens all in one allowable range for the material used, shorten or extend the corresponding elements are reversible. There will be energy in this Items saved. The pressure and tension elements act as compression springs or as elastic spring elements and cause the spring effect per connecting element. If the critical dead center is reached, the flip-flop jumps without further action in the open position.

The proportion and arrangement of the pressure 2.1, 2.2 and tension elements 3.1, 3.2 are determined in such a way that optimized angles of action and snap forces occur. It is essential that the pressure forces required in the pressure element initiated and can be recorded without kinking. This is the Consider the thickness of the pressure elements in relation to the thickness of the tension elements. A too small thickness of the pressure elements leads to unfavorable snap behavior. The dashed auxiliary lines entered in FIG. 1 through the end points of push and pull elements of one connecting element 5.1, 5.2 enclose an angle , which is explained further below, according to the invention used to achieve the desired partial angle of a flip-flop becomes. Furthermore, in order to achieve an optimal snapping force by two normal to each by the pressure elements 2.1, 2.2 and the tension elements 3.1, 3.2 spanned planes standing vectors 30 and 31 in the End positions of the closure included wrap angle of Meaning. When constructively implementing the invention, care must be taken that in a printing element, e.g. B. caused by eccentric pressing Bending stresses, by means of suitable technical measures are prevented from causing the pressure element to buckle. For special ones Applications can print elements 2.1 and 2.2 with each other be connected. This connection can preferably be pressure-resistant or kink-resistant Plate be executed and form a unit with the pressure elements. This pressure-resistant plate is partially or, if desired, over its whole Width on the links 20 and 21 by means of suitable hinge elements be attached.

When looking at conventional hinge systems for plastic closures, one can see that closures of different shapes or designs, even if they are based on the same principle, have very different snap effects and different snap forces. Certain versions of these closures even completely miss a snap effect, although this is an explicit target of corresponding patent specifications. The reason for this lies in the complex mechanical processes on which such hinges are based, or in the fact that the hinge parts themselves make a significant contribution to the functioning of the closure and thus, even with slight changes in geometry, effects which are not easy or unforeseeable occur. These disadvantages are eliminated by the present invention in that the functionally essential elements are reduced to a minimum and are concentrated locally and in their spatial extent, but at the same time allowing more flexible movement sequences compared to conventional hinge principles. This is particularly true in contrast to snap locks with fixed main axes of movement, which always describe a rotational movement with a spatially fixed axis of rotation relative to one another.

The operating principle of flip-flop 1 is based on the presence of a or several pressure-loaded pressure elements 2.1, 2.2, which work in combination stand correspondingly arranged tensile elements 3.1, 3.2. By pushing and pulling elements in their spatial expansion and dimensioning are coordinated, it is achieved that pressure and Tensile forces are specifically introduced. With unwanted movements, it is unavoidable that secondary pressure loads also act on the tension element. However, these undesirable forces are much smaller than those in normal Operation occurring tensile loads and are intended with regard to Function of the hinge negligible. The same applies to the printing elements. To protect the hinge mechanism against shearing and around Preventing improper movements is at least 1 per level a thrust element 4.1, 4.2 is provided. It can be used, for example, with plastic injection molded parts formed as a thin, rigid shear membrane or thin point become. This thrust element 4.1, 4.2 is essential for the invention by preventing undesirable movements and coordinates the locking parts around their virtual movement axis. The thrust element can, as in FIG. 1, connect a tension element with a pressure element directly, or be provided elsewhere. The resilience and the total angle of action, hence the snap effect of a flip-flop According to the invention essentially only with the aid of pressure and tension elements and not achieved by spiral springs.

A preferred embodiment of a flip-flop is shown in Figure 2 and Figure 3. The two figures show the tilt level 1 once in the closed State (Figure 2) and in the open state (Figure 3). It contains two printing elements 2.1 and 2.2 and two tension elements 3.1 and 3.2. The corresponding Push elements 4.1, 4.2, which the necessary interaction of the pressure and ensure tension elements are formed by shear-resistant membrane the in this embodiment for visual reasons, especially if the hinge is injection molded from plastic, as a thin, continuous membrane are formed. The resulting essentially trapezoidal elements have a pronounced stiffened pressure side and a pronounced, relatively thin elastic tension side on. The flip-flop 1 then consists of two connecting elements 5.1, 5.2, which by thin points 10 with the rigid intermediate members adjacent to the tilting stage 20.1, 21.1 are connected. The strain on the thin areas 10 can by means of suitable geometry or pressure or tensile rigidity of the essential Elements are kept within a permissible range. Excessive Forces can be caused by plastic deformation in certain areas permissible part of the thin points are reduced. The pressure elements 2 are constructed in such a way that they do not buckle under normal operating loads can. FIG. 3 shows clearly how the flip-flop around the thin areas 10 is moved and comes to rest in its open position. Both the in the positions shown in FIG. 2 as well as in FIG. 3 are all elements the flip-flop essentially free of tension. During the tipping process in principle neither bending effects in the pontics 20.1, 21.2 nor in the connecting elements 5.1, 5.2 required. A bending or buckling the fasteners do not occur.

A possible relative movement of the hinge parts 23, 24 of a hinge 25.1 is shown schematically in FIG. 4. The hinge parts 23, 24 are connected here via two tilting stages connected in series. The first flip-flop is made up of intermediate links 20, 21 and connecting elements 5.2. The second flip-flop is made up of intermediate links 21, 22 and connecting elements 5.1. Figure 4 shows three states of tilt of the hinge. The hinge is shown in the closed state 25.1, in the first tilting state 25.2, ie with the first tilting stage open, and finally in the open state 25.3, in which both tilting stages are open. The opening path of the hinge is illustrated by the spatial curve or arrow 32. This opening path 32 can be significantly influenced by the arrangement and design of the partial tilt stages. It can be seen in FIG. 4 that the opening path shown deviates greatly from conventional, circular opening paths, which were imposed in particular on hinges with a fixed main movement axis. In contrast to other known hinges without a main axis, there is nevertheless a defined movement path. The first flip-flop, which is formed from the connecting elements 5.2 and the intermediate members 20, 21, either has a smaller snap force or the same snap force as the second flip-flop consisting of the connecting elements 5.2 and the intermediate members 21, 22, but then has one geometrically determined earlier snap effect. When the hinge is opened, the first tilting step jumps to its open state first. All three tilting states shown in FIG. 4 are essentially stress-free by using the relationships according to the invention to be explained below.

FIGS. 5 and 6 now show an application of such a tilting step for one one-piece sprayable plastic snap closure 25 shown. Of the Closure 25 contains two hinge parts, namely the closure body 24 and a corresponding cover 23. A fill opening 16 on the closure body 24 should cooperate with a counterpart 16 of the cover 23. The Hinge parts are separated by a closure level 15. The closure here has a single flip-flop, which connecting elements 5.3 and 5.4 contains. The connecting elements 5.3, 5.4 are via thin points 10 with the Cover 23 or connected to the closure body 24. Since there is only one Tilt level is present, are the intermediate links described above replaced by the cover 23 or the closure body 24 itself. The geometry This flip-flop enables a total angle of effectiveness of over 180 ° and thus an opening angle of approx. 200 ° here, so that the closure in the open position (FIG. 6) inclined downwards relative to the closure plane is and makes the fill opening 16 fully accessible. Is the clasp ideally designed so that no or minimal plastic deformation when the lock is actuated, so is the opening angle (Position during injection molding) and the angle of action of the flip-flop the same large. A bevel 18 allows the without major tool effort To manufacture plastic lids so that the aforementioned open position can be achieved can mutually without the outer walls of the closure parts hindrance. Of course, it is possible to use an appropriate closure can also be sprayed in a 180 ° open position, if this is due to tool technology Reasons is desired. The connecting elements 5.3 and 5.4 exist each from the very flexurally rigid pressure elements 2.3, 2.4, the tension elements 3.3, 3.4 and intermediate shear membranes 4.3, 4.4. The The outside of the connecting elements 5.3, 5.4 is flat and structured fits perfectly into the outer contour of the closed plastic cover. Of the Cross section of the plastic cover in Fig. 4 and 5 is for the application of the The tilt level shown here is optimal, as there are thin spots 10 and the optimal wrap angle can be realized. This type of flip-flop can be but also combine with other closure geometries. It is quite possible circular cross sections, or other cross sections than described here to use or slightly curved thin spots 10 or at their Place other joint means to provide. To get a good snap effect too ensure that the thin points are ideally designed as ideal joint axes. Of course, corresponding, functionally equivalent can also be used for this Measures are taken. With curved outer contours the connecting elements can be shaped accordingly. A special The advantage of the invention is that the connecting elements 5.3, 5.4 basically can be arranged freely from the position of the closure level. It is possible, for example, in the vertical direction against the closure body 24 to move and fully integrate into this, which is great freedom with regard to the closure geometries and design options. Out FIGS. 5 and 6 clearly show that in the closed state the Tilt level is perpendicular to the hinge parts or to the locking plane and here passes directly into the rigid closure body 24 or cover 23.

Another preferred exemplary embodiment of a flip-flop 1 is shown in FIG. This tilting stage contains two pressure elements 2.1, 2.2 and two tension elements 3.1, 3.2, which are each arranged parallel to one another. The flexurally rigid pressure elements 2.1, 2.2 are located directly next to a central hinge plane and are connected to one another via a thin point 11. This middle plane does not necessarily have to coincide with the symmetry plane. In this preferred embodiment, a pulling element 3 can be connected to a pushing element 2 by a thin shear-resistant membrane for aesthetic reasons. Of course, in this and in other embodiments the wall thicknesses can be varied, it being necessary to ensure that the functions of a tilting step that are essential to the invention are retained. It is possible, for example, to design the push element 4.1 with a wall thickness corresponding to the wall thickness of the tension element 3.1, 3.2 or greater in some areas, as long as the functional tensile elasticity of the tension element 3.1, 3.2 remains guaranteed. The connecting elements 5.1, 5.2 here are directly connected to one another via the thin point 11 and each have a pronounced, stiffened pressure side and a relatively thin, elastic tension side.

Another preferred embodiment of a flip-flop consists of two Tension elements and two pressure elements, the latter rigidly connected together are. The pressure elements that are integrated in this way and are designed to be rigid are in the middle plane (but not necessarily the plane of symmetry) of the hinge and are with two perpendicular to the main plane of movement Thin points attached to the adjacent rigid pontics. Connects the tension and compression elements over their entire length by a shear-resistant thin membrane, and if you connect the membrane with thin areas with the pontics so there is a trapezoidal area that the tension element and the thrust element.

On the basis of the following FIGS. 8-11, the concept of the invention should be comprehensive Meaning are shown. The mode of action is based on a Special case of a flip-flop explained in more detail. Basically, by special choice of geometry angles and lengths of partial angles, the snap force and the material load of a flip-flop can be varied. It's supposed to be here be emphasized again that each flip level is basically only one Partial angle of the entire hinge movement recorded. In the following, The simplest case of a single flip-flop corresponds to the partial angle of Flip-flop, however, the overall angle of effect. The necessary relationships are explained below.

Figure 8 shows schematically an embodiment with only one flip-flop only the part of a connecting element 5 is shown here. The flip-flop is characterized here by two planes of symmetry 40, 41. These levels of symmetry 40, 41 generally remain in any open position of the hinge receive. This version has a (theoretical) angle of action of 180 °. It is further assumed that under one position with an opening angle of 0 ° the drawn closed state and an open position means an opening angle of 180 °. At the explanation of the operation of this particular embodiment is based on the two planes of symmetry referred to. This way of looking at things enables the function to be explained based on a sub-problem. For the sake of simplicity, a push and pull element are each as in one plane lying and interpreted as a geometric unit. The following parameters are of importance for the invention. On the one hand, the angle  between those assumed here two thin points of an intermediate link or the one through the end points The lines of the pressure and tension elements define included angles. The wrap angle ω is that which can be seen in a top view of the hinge Angle between the levels of the pontics in closed Position (see FIG. 1, arrows 30, 31). If the intermediate links 5 for others Embodiments are not perpendicular to the hinge parts or pressure elements 2 and tension elements 3 are not aligned parallel to each other, is the determination of the angle ω accordingly. In the present one, parallel arrangement of the pressure and tension elements are those by the pressure elements spanned plane and the spanned by the tension elements Level (not shown in detail in Figure 8) accordingly against each other spaced. Both angles largely determine the constraint (and thus the snap force) on the pontics and the opening angle. The planes of symmetry are shown in Figure 8. The plane of symmetry 40 is during the stationary plane of symmetry of the flip-flop throughout the entire sequence of movements. It generally forms the plane of symmetry between the connecting elements 5.

The plane of symmetry 41 is movable and forms in every state of motion the second plane of symmetry. It forms the plane of symmetry of each connecting element 5 to itself. From Figure 8 is its position in the closed Position 41.1 and in the open position 41.2 of the flip-flop.

Due to the symmetry conditions, the functionality is based on a Partial model considered, which makes up a quarter of the flip-flop. This Partial model is shown in Figure 8. It shows half of an intermediate link 21 and part of a connecting element 5. The model shown describes approximately the mechanical processes of the flip-flop. Contexts and the constraint caused by the snap force is modeled below. The material is forced upon it Understood deformation, which is an elastic (reversible) Causes state of tension. The material resists the forced one elastic deformation, on which the snap effect is based. According to the invention specific tension and pressure zones are formed. The as pressure zones designated areas are designed so that a buckling out their level is prevented. The areas called train zones can are varied in length and thickness so that, due to the geometry, forced stretch the material load within the elastic (reversible) Material behavior remains. With regard to the plane of symmetry 41 symmetrical design of the flip-flop ensures a good snap force, by avoiding a double hinge effect within the tilting step.

It is assumed that for the model presentation the hinges active thin points 10 are considered as ideal hinges. Under a Ideal hinge is understood to be a hinge that has no internal friction and does not experience any stretches in the hinge parts themselves. So it will be off assumed that the rotational movement of all points smoothly by one fixed axis 10 happens. The parts referred to as links 21 are assumed to be non-deformable. Each of the connecting elements 5 is considered as a stretchable element in its plane in the train area. The fasteners 5 always stay on one level, so that bending out this level is considered as not permitted.

The reference numbers * .1 each refer to elements in the closed position, those with * .2 on elements in the open state. The reason for the squeeze can be best understood when looking at a point P in space becomes. This point P lies on the line of symmetry 43 of the intermediate members 5 and in the movable plane of symmetry 41. Its position depends on the opening angle the flip-flop. The position of P on the line of symmetry plays for these considerations have no relevant meaning. P would, due to the Hinge condition which he is subject to move on the circular path k1 Center at point A and the hinge axis 10 as the axis of rotation. Due to the according to the invention forced symmetry conditions of the flip-flop the point P, however, is forced on a curve k2, which in the model is a circle with center in B is approximated.

A straight line e2 between the stationary point B and the movable one Point on k2, which is not shown in Figure 8 for the sake of clarity was (see FIG. 9), forms the flip-flop at every opening angle the point normal to plane 41 on plane 41. This straight line e2 moves together with the connecting element 5. A straight line e1, between the stationary point B and the moving point on k1 describe the straight line e2 if it were not subject to any constraint. In Figure 8 is also half the wrap angle ω / 2 and the angle  / 2, which significantly influence the snap effect, clearly recognizable.

Figure 9 shows schematically the constraint state of half the connecting element 5. The reference number 43.3 is the position of the line of symmetry 43 depicted as a result of the squeeze. The pressure and tension areas are also lines 2, 3 of the connecting element 5 shown. The constructive location of the Point P for determining the angle κ does not of course have to be lie in the middle of the section of the symmetry line 43 shown here. The location, however, depends on the material thickness selected Pressure and tension areas 2, 3 and is determined by the neutral point on the straight line 43. The point becomes the neutral point here understood in which the stresses along the line 43 in equilibrium are.

Figure 10 now shows the relationships in a schematic partial representation a flip-flop with an opening angle γ less than 180 °. The opening angle γ of a flip-flop can be selected according to the requirements. According to the invention in the closed and in the open position of a tilting stage To achieve two stress-free states is described below Context must be fulfilled. These relationships according to the invention are also intended for an opening angle γ of more than 180 °. Next the intermediate member 21 only partially shown here is half of a Connection element 5 shown in closed 5.1 and 5.2 in the open position. The intermediate member 21 and the connecting element are via a Hinge axis 10 connected.

For two tension-free states of the flip-flop, the relationship between the opening angle γ of a flip-flop, the wrap angle ω and the angle  of the connecting elements is defined by the following formula:  = 2 * arctan [ Sin (γ / 2) 1-cos (γ / 2) * sin (ω / 2)]

FIG. 11 shows a typical course of the constraint angle κ of a flip-flop as Function of the angle ω and the opening angle γ of a flip-flop shown. It is assumed that an angle  is selected, which to leads the tension-free end positions according to the invention. As already shown κ means a measure of the constraint of the material. Given The wrap angle ω is in the points with a horizontal tangent given the maximum squeeze of the material and the dead center of the snap force. The dead center lies in half the opening angle γ of the flip-flop.

Figures 12-14 show a hinge with two tilt stages 1.1, 1.2 with stiff Intermediate links 20, 21 and 22, and two hinge parts 23, 24. Of course the tilting steps can also pass directly into the hinge parts. The flip-flops are shown schematically and correspond, for example the flip-flops as described with reference to Figures 2 and 3. The hinge is shown in Figure 12 in the closed state. Jump the Tilt level 1.1 in its open state, then the first corresponds theoretically stress-free tilting state of the hinge the state shown in Figure 13. In this tilted state, no external forces act on the hinge on. The flip-flop 1.1 is fully open and the flip-flop 1.2 is still full closed. The hinge shown in Figure 13 has a first partial snap effect already effected. If you open the hinge further, you reach one more dead center and the hinge jumps into another in essential stress-free tilting condition, corresponding to Figure 14. In the in The hinge shown in Figures 12-14 is the fully open tilt condition. The opening angle of the schematically drawn hinge is much more than 180 °.

The invention prefers, in particular in the case of one-piece injection-molded hinge parts, to provide a total effective angle of 180 ° in order to close the tool shop simplify. For manufacturing reasons, geometries of the flip-flops are to be preferred, such as those shown in Figures 2, 3, 7 Exemplary embodiments, have as few articulation points as possible. A particular advantage of the invention is that at low and maintenance-friendly, tool-related effort thanks to the concentration of the functional elements while largely avoiding slits or Recesses in closures, especially those adjacent to the hinge Areas where a good seal can be brought about. The Seal can be preferred, with further avoidance of recesses, through measures such as those in the international patent application PCT / EP 95/00651 are provided. For special ones Embodiments can also the described tension and compression elements not parallel, but at an angle to each other. For elongated ones Hinge parts can also have two or more tilt levels next to each other to be ordered. The individual elements arranged side by side the flip-flops can have no connection with each other or, if desired, connected by means of a non-functional membrane be. It is therefore conceivable to combine several tilting stages in their mode of action, for example to increase the snap effect.

Claims (12)

1. Resilient hinge arrangement without a principal hinge which comprises at least two hinge parts and connecting arms which connect said hinge parts, characterized by one or a plurality of series connected tilting units (1) each comprising at least two connecting elements (5), each of which comprises a flexurally rigid pressure element (2) and a tensionally elastic tension element (3), each of which is attached, via a hinged connection, either to intermediate members (20) or directly to the hinge parts (24, 25), and is arranged to be at least substantially rigid under axial loads by means of at least one associated pushing element (4).
2. Hinge arrangement according to claim 1, characterized in that the intermediate members (20) and the tilting units (1) are substantially stress-free not only in the open position but also in the closed position.
3. Hinge arrangement according to claim 1 or claim 2, characterized in that the pressure (2) and the tension elements (3) of a tilting unit (1) are arranged parallel with respect to each other, and the planes defined by the pressure elements (2) and by the tension elements (3) are spaced away from each other.
4. Hinge arrangement according to one of claims 2 to 3, characterized in that the connecting elements are arranged in pairs (5), the connecting elements of which are pivotingly interconnected via a hinge axis (11) which is disposed parallel with respect to a principal movement plane.
5. Hinge arrangement according to one of the preceding claims, characterized in that the angle Φ, which is encompassed by the lines defined by the end points of the pressure elements (2) and the tension elements (3) has a value which complies with the following formula =2*arctan[sin(γ/2)1-cos(γ/2) *sin(ω/2)] wherein ω, in a plan view of the hinge, is the projected angle between two normal lines on to the planes defined by, in each case, one pressure (2) and tension element (3) and γ is the opening angle of tilting unit.
6. Hinge arrangement according to one of the preceding claims, characterized in that the pressure elements (2) and the tension elements (3) are arranged relative to each other such that, in each opening position, a plane (41) of symmetry, which is moving and is disposed perpendicularly relative to the principal movement plane, forms the plane of symmetry for the pressure elements (2) and tension elements (3) with respect to themselves.
7. Hinge arrangement according to one of the preceding claims, characterized in that the pushing element (4) is designed to be a membrane which is rigid under axial loads and which connects the pressure (2) and the tension element (3) along their entire length.
8. Hinge arrangement according to one of the preceding claims, characterized in that the pushing element (4) is connected to the intermediate members (2) via elongate regions of reduced thickness and to the tension element (3) without any direct connection to the pressure element (2).
9. Hinge arrangement according to one of the preceding claims, characterized in that the pressure elements (2) of a tilting unit (1) are substantially rigidly interconnected.
10. Hinge arrangement according to one of the preceding claims, characterized in that a plurality of tilting units (1) are interconnected such that the hinge arrangement has a number of stress-free states which corresponds to the number of its tilting units, and in that dead centres are disposed between two such states, respectively, and in that the hinge arrangement, beyond each such dead centre, automatically and resiliently assumes the next adjacent stress-free state.
11. Hinge arrangement according to one of the preceding claims, characterized in that the pressure element (2) is connected to the tension element (3) and has the same wall thickness as the tension element.
12. Use of a hinge arrangement according to one of the preceding claims for a one-piece injection-moulded plastics closing means.

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