Patent ID: 12189214

DETAILED DESCRIPTION

In the following, various embodiments of an eyeglass joint for an eyeglass frame will be discussed. Parts with the same function and/or identical design are partly assigned identical reference numbers and subsequently, redundant descriptions for each embodiment are left out.

FIG.1shows a schematic perspective view of a first embodiment of an eyeglass joint10for an eyeglass frame. The eyeglass joint comprises a first joint part12, which is assigned to a frame of the eyeglass frame. Furthermore, the eyeglass joint10comprises a second joint part14, which is assigned to an eyeglass temple of the eyeglass frame. However, this assignment can easily be exchanged without restricting the functionality of the respective eyeglass joints.

For example, the first joint part12may be formed integrally with the rim of the eyeglass frame, wherein the rim serves to hold the respective lenses of eyeglasses and at least a partial portion of which rests on the nose of the wearer when the glasses are worn. The second joint part14can also be formed integrally with an eyeglass temple and serves to hold the eyeglass frame on the head of the wearer. For example, both the first joint part12and the second joint part14can uniformly consist of a single material, such as wood, in particular compressed wood, Panzerholz wood, stone, horn, plastic, and/or metal. Accordingly, the rim and the respective eyeglass temples can be made of the same material.

The two joint parts12,14are movably connected by means of a spring element16attached to the two joint parts12,14. The spring element16of the present invention has a closed annular shape and is formed from a rubber-elastic material. For example, different types of rubber are suitable as a material for the spring element16. The spring element16is provided on a retaining element18on each of the two joint parts12,14. The two retaining elements18comprise an undercut20on the sides facing away from each other, which prevents the spring element16from slipping off the retaining elements18. By means of the spring element16, the two joint parts12,14are tensed against each other in a contact area. For this purpose, the spring element16is attached to the two retaining elements18with a certain preload. That is, the spring element16is stretched compared to an unstressed, loose state.

Except by the spring element16, the two joint parts12,14are not connected to each other. Since the spring element16is elastic, it allows the relative movement of the two joint parts12,14basically in all degrees of freedom. In particular, the two joint parts12,14can be adjusted between a use position, in which respective eyeglass temples are folded away from the frame and the glasses can be placed on the head of a wearer, and a stowage position, in which the eyeglass temples are substantially in contact with the rim of the eyeglass frame or folded towards the respective lenses.

The stowage position of the eyeglass joint10can for example be seen in the schematic perspective view ofFIG.2, wherein the two joint parts12,14are rotated relative to each other by 90° in a movement plane compared to the use position shown inFIG.1. In order to guide the movement of the two joint parts12,14relative to each other at least partially, the first joint part12has a rolling portion22and the second joint part14has a corresponding receiving portion24. As can be seen inFIGS.1and2, as well as in the schematic views according toFIGS.3and4, the rolling portion22is substantially cube-shaped or cuboid. Accordingly, the receiving portion24comprises a corresponding recess with a rectangular cross-section. Any corners are rounded in order to allow as uniform a smooth sliding and/or rolling of the two joint parts12,14against each other as possible. Due to the corresponding cuboid formation of the rolling portion and the receiving portion, at least two pairs of corresponding support surfaces36,22are provided, which when resting on each other form the stowage position or the use position, as described below. The respective support surface pairs are preferably formed in the cuboid embodiment at an angle and are for example substantially offset by 90° to each other.

The receiving portion24and the rolling portion22form a kind of guide for the eyeglass joint10. In particular, these two portions22,24stabilize the joint parts12,14with respect to a tilting movement upwards or downwards, which is for example illustrated inFIG.2by the arrow26. This ensures that the eyeglass joint10can be conveniently adjusted between the use position and the stowage position without the eyeglass joint being inadvertently twisted in a different spatial direction.

The two holding elements18each form a part of the rolling portion22and the receiving portion24and each have contact surfaces facing each other.

Since the two joint parts12,14are held together only by the spring element16, a movement of, for example, the second joint part14relative to the first joint part12in the direction of movement illustrated by the arrow26is quite possible. The eyeglass temple can thus be bent upwards or downwards in relation to the rim, wherein respective spatial orientations are to be understood according to a wearing position of the eyeglass frame on the head of the wearer. This allows the eyeglass joint10to be protected against damage if unintentional forces act on one of the two joint parts12,14in the upward direction.

Due to the respective flat support surfaces in the upward direction at the rolling portion22and the receiving portion24, and a further elongation of the spring element16resulting from such a movement, a resetting force is generated, which automatically adjusts the respective joint parts12,14of the eyeglass joint10back into the movement plane between the use position and the stowage position. This movement plane is substantially horizontal with respect to a carrying position of a wearer standing upright. Thus, the eyeglass joint is particularly robust and easy to handle.

Furthermore, it can be seen that the rolling portion22and the receiving portion24in the section28form a stop28, by means of which the stowage position is predetermined as a resting position. Due to the preload of the spring element16, the eyeglass joint10will automatically engage back into the stowage position after an adjustment from the use position by a certain angle range or into a certain joint position range. Subsequently, the eyeglass joint10is automatically held in the stowage position by the spring element16on the stop28. Thus, a metastable position is provided, which the eyeglass joint or respective joint parts12,14only leave if an external force with a certain minimum strength is exerted. The angular range, from which the eyeglass joint10automatically engages into the stowage position, is substantially specified by the flat surfaces of the cubic shape of the receiving portion24and the rolling portion22. For example, after passing a specific corner of the receiving portion24at a corresponding corner of the rolling portion22, the eyeglass joint10engages from one position to the other.

Similarly, the eyeglass joint10also has a metastable position in the use position. For example, in the top view ofFIG.3, it can especially clearly be seen that the receiving portion24with two flat or plane surfaces36is in contact with the corresponding flat surfaces of the rolling portion22. In this position, the spring element16can for example have its least elongation. Thus, for adjusting the eyeglass joint10from the use position, an increased tensile force is automatically generated by the spring element16, which first causes a resetting force back into the use position. The use position is specified by the geometry of the rolling portion22and the receiving portion24. In particular, the angled flat surfaces36create a stable position of the two joint parts12,14to each other in the use position. The eyeglass joint10also automatically engages into the use position at a certain angle range, with the surfaces36serving engaging surfaces and ensuring a stable position of the two joint parts12,14to each other.

Furthermore,FIG.3also shows that the rolling portion22and the receiving portion24are beveled when viewed from the direction of the arrow30. The arrow30illustrates from which direction the eyeglass joint10is substantially seen by another person, as long as an eyeglass frame provided with it is worn by a user. In other words, the direction of view extends, for example, vertically to the longitudinal direction of an eyeglass temple. Accordingly, a possible gap between the two joint parts12,14is concealed by a bevel. As a result, potential manufacturing tolerances can be particularly large, as no unsightly gap can be seen. In addition, the two joint parts12,14are also pressed against each other by the spring element, so that the lowest possible gap is adjusted automatically.

In addition, this arrangement results in a V-shaped hold, by means of which the joint parts can be kept stable.

In the top view of the eyeglass joint10according toFIG.4, it is further shown that an portion32facing away from an inner angle of the eyeglass joint10in the stowage position has no overlap between the first and the second joint part12,14. This makes it possible for the eyeglass joint10to be folded even further without causing a structural load of adjacent portions of the two joint parts12,14. In particular, no contact area experiences any tensile load; instead the two joint parts12,14roll on each other at the stop28when the eyeglass joint10is compressed over such a predetermined portion. In the portion32, the two joint parts12,14can withdraw from each other in order to structurally relieve the eyeglass joint10. Thus, the eyeglass joint10is also protected against damage. Usually, a spring element16can easily be designed to be stretched further without being damaged while still providing enough preload force.

The spring element16is detachably connected to the two retaining elements18or to the two joint parts12,14. Thus, it is possible, in particular, to replace the spring element16with another spring element with a different spring characteristic curve. For example, spring elements16consisting of from different rubber compounds can be provided, whereby these different spring elements generate different forces at the same elongation. Thus, one the one hand, depending on the used spring element, a different force can be specified with which the eyeglass joint10engages into the use position and/or the stowage position, respectively, and in addition, which corresponding force is needed to adjust the eyeglass joint10between these positions. Likewise, it can also be provided that a certain force is necessary to keep the eyeglass joint10in the use position. Thus, it can be effected that respective eyeglass temples are pressed to the head of a wearer in order to help hold a corresponding eyeglass frame to the head of the wearer.

The eyeglass joint10can easily be assembled and disassembled. In particular, it can be possible to assemble the eyeglass joint10without additional tools and/or training. This also makes it possible for a home user to replace individual parts of the eyeglass joint10, such as the spring element16. The eyeglass joint10adjusts itself via the receiving portion24and the rolling portion22as well as the spring element16, so that no further fine adjustments and adjustments of the eyeglass joint10to its wearer by permanent deformation of respective parts of the eyeglass joint10are necessary. As a result, the eyeglass joint10can also be configured by a home user.

As is shown in particular inFIGS.1and2, the two joint parts12,14each comprise a groove34, in which the spring element16is arranged. Thus, the spring element16is recessed against the respective outer surfaces of the two joint parts12,14, which on the one hand protects the spring element16against damage, and on the other hand, also prevents hair from getting caught in the spring element16. The grooves34can also be understood as recesses in the two joint parts12,14, in the center portion of which the corresponding holding elements18are arranged. The grooves34and/or the retaining elements can be manufactured by milling the respective joint part blanks, in particular Panzerholz wood blanks.

The groove34on the first joint part12is designed in such a way that in the stowage position, it is no longer accessible from the outside at the eyeglass joint10. This can be seen in particular inFIG.2. Thus, the spring element16is protected from slipping out of the groove34or from sliding off the retaining element18on the first joint part12in the stowage position. This is particularly useful if the spring element16is less stretched in the stowage position than in the use position, as is the case in the present case. If the stretch ratios are reversed, a reverse construction or a blocking of the groove34on the first and/or second joint part14in the use position can also be provided: In that case, the groove34of the second joint part14can for example be covered in the use position.

As can be seen inFIG.1, is recognizable, the holding element18at the second joint part14of the eyeglass joint10extends further away from the respective contact surfaces of the two joint parts12,14than the holding element18of the first joint part12. This makes it possible to take into account that there is more assembly space on an eyeglass temple than on a rim, since the rim also has to accommodate the respective lenses and also usually has a curvature of approx. 90° as it meets the first joint part12. With this wide extension of the spring element16at the second joint part14, a longer spring element16can be used. When a longer spring element16is used, it is stretched, or elongated, less in terms of its total length than a correspondingly shorter spring element during a movement of the eyeglass joint10. As a result, the spring element16is less stressed overall. In particular, the rubber-elastic material from which the spring element16is formed will not experience material fatigue until after a high number of joint movements.

In a schematic perspective view,FIG.5shows a second version of the eyeglass joint, wherein it is provided with the reference number50. In the eyeglass joint50, the rolling portion22is arranged on the second joint part14and the receiving portion24on the first joint part12. Thus, the arrangement is reversed compared to the eyeglass joint10. Alternatively, the joint part12can also be assigned to the eyeglass temple and the joint part14to the rim. In that case,FIG.5shows, for example, a left eyeglass joint50, whileFIG.1shows a right eyeglass joint10. Respective left and right eyeglass joints are preferably formed symmetrically with respect to a mirror axis through the center of a rim.

Analogous to the figures of the eyeglass joint10, the eyeglass joint50inFIG.5is shown in its use position,FIG.6shows a schematic perspective view of the eyeglass joint50in its stowage position,FIG.8shows a schematic top view of the eyeglass joint50in its use position, andFIG.9shows a schematic top view of the eyeglass joint50in its stowage position. The top view can correspond to a top view from above in the upward direction of the user wearing the glasses and standing in an upright posture. Due to the symmetrical design, the representation in the top view also corresponds to a bottom view.

As can be in seen in particular inFIG.5andFIG.6, the eyeglass joint50not only comprises the stop28, but also the additional stop52. By means of the stop52, the use position is specified particularly precisely and the eyeglass joint50is additionally stabilized in this position.

Furthermore, it can be seen that the two joint parts12,14taper on a side facing away from the respective contact surfaces, in particular transversely to the main extension direction of the two joint parts12,14or substantially orthogonally to a vertical plane when worn in an upright position. This tapering results in a particularly delicate appearance of the eyeglass frame. The tapering can be designed in particular with respect to a structural load of the respective joint parts12,14, which is particularly high in the portion of the respective contact surfaces and thus in the portion of the rolling portion22and the receiving portion24but which becomes smaller, in relative terms, on the respective sides facing away. Thus, the eyeglass joint50can have a particularly low weight.

In addition, compared to the first embodiment (eyeglass joint10), the respective retaining elements18and grooves34are designed differently in the eyeglass joint50.

The retaining elements18of the eyeglass joint50have no undercuts20. Instead, the retaining elements18are slightly inclined in relation to a plane formed by the spring element16(which is difficult to see inFIGS.5to9and therefore is not provided with a reference number, but is arranged in the grooves34) in the use position. Similarly to the undercuts20, this inclination (70) of the retaining elements18first causes a retention of the spring element16in the respective grooves34. However, if the eyeglass joint50is pressed together beyond the stowage position, i.e. if the two joint parts12,14are folded closed onto each other beyond the position shown inFIG.6andFIG.9above, the spring element16can slip off the retaining elements18by itself. As a result, the two joint parts12,14are separated from each other, whereby damage to the eyeglass joint50can be avoided if it is over-compressed. Subsequently, the spring element16can be simply pulled over the retaining elements18again to disassemble the eyeglass joint50. This makes the eyeglass joint50particularly robust. In total, the assembly and disassembly of the spring element16is simplified due to the slanted retaining elements18compared to the eyeglass joint10comprising the retaining elements18with the undercut20.

Furthermore, the groove34on the first joint part12is formed such that it comprises an undercut54on a side facing the second joint part14. For assembly and disassembly, the spring element16therefore has to be threaded through a middle gap56, which can also be called an opening56. In the mounted state of the two joint parts12,14, this middle gap56is closed by the holding element18of the second joint part14, at least in the normally intended joint positions. The normally intended joint positions are usually the stowage position, the use position, and all the positions in between in the movement plane. The retaining element18of the second joint part14at the eyeglass joint50thus glides through the middle opening56, thus additionally connecting the joint parts12,14in a compact design. Accordingly, the spring element16must first be arranged on the first joint part12for assembling the eyeglass joint50and only then on the retaining element18of the second joint part14. This ensures that the spring element16is not released unintentionally or lost.

At the same time, the undercut54serves to provide a further preload of the spring element16of the eyeglass joint50in the stowage position as well. The undercut54thus ensures that the spring element16must substantially follow the contour of the two grooves34in the stowage position of the eyeglass joint50. Otherwise, the spring element, for example, would be arranged at least partially outside the grooves34in the stowage position of the eyeglass joint50. Such a course of the spring element16is, for example, illustrated by the dotted line58inFIG.9. However, due to the undercut54, the spring element16follows the course illustrated by the dotted line60. Thus, a sufficient preload of the spring element16can also be ensured in the stowage position, in order to hold the two joint parts12,14together without requiring a strong preload in the use position. This relieves the eyeglass joint50. In addition, the spring element16is still arranged in the grooves34in the stowage position of the eyeglass joint50and thus protected against damage.

Thus, the spring element16of the eyeglass joint50is supported by the undercut54only in a certain joint position range, which is in particular adjacent to the stowage position. For further illustration of the grooves34, the retaining elements18and the undercut54of the eyeglass joint50, it is also shown in a perspective interior side view inFIG.7.

Furthermore, it can for example be seen especially well inFIG.8that a certain gap is provided at the corner between the plane support surfaces36of the rolling portion22and the receiving portion24a certain gap is provided in the eyeglass joint50. This gap allows a particularly uniform adjustment between the stowage position and the use position, i.e. the respective joint parts12,14can be moved particularly evenly relative to each other. On the other hand, with an unrounded corner and/or a gap-free fit, the joint parts could easily get caught and/or jerk during the adjustment of the eyeglass joint50.

The third embodiment of the eyeglass joint shown in the schematic perspective view according toFIG.10, which has been assigned the reference number100, differs from the first two embodiments in particular in that the two joint parts12,14are now connected by means of a first spring element102and a second spring element104. This can be seen particularly clearly in the schematic top view of the eyeglass joint100according toFIG.12, which also shows the eyeglass joint100in its use position. The third embodiment of the eyeglass joint100is also shown in its stowage position in the schematic perspective view according toFIG.11. Similarly, the schematic top view ofFIG.13shows the eyeglass joint100in its stowage position.

The two joint parts12,14each have a holding element18, each of which comprises an undercut at which the inner spring element102is supported at a side facing in the head of the wearer when the eyeglass frame is worn. On a side facing away from that side, the corresponding second spring element104is supported, so that both spring elements102,104are safely incorporated in a recess106surrounding the two retaining elements18. The two joint parts102,104additionally comprise a torus-shaped indentation108at the recess106, by means of which the spring element104is additionally fixed in its position in the recess106. This torus-shaped indentation108can be formed as a circumference according to the ring form of the spring element104, or only at the sides of the recess106facing away from the rolling portion22and the receiving portion24.

In addition, the receiving portion24and the rolling portion22are visibly different in the eyeglass joint100. In the eyeglass joint100, the rolling portion22and the receiving portion24do not form straight engaging surfaces, which in turn specify a use position and/or stowage position of the eyeglass joint100. Instead, the use position of the eyeglass joint100is only determined by the stop110, as can be seen inFIGS.10and12. The stowage position of the eyeglass joint100, shown in the schematic perspective view according toFIG.11and in the top view according toFIG.13, is specified by the alternating recesses and elevations in a center portion on an inner side of the eyeglass joint100, which are indicated here with the reference number112. These alternating elevations and recesses in the portion112also form support surfaces114at the same time, which are arranged substantially parallel to the movement plane of the eyeglass joint100between the stowage position and the use position. These support surfaces114serve to additionally support the eyeglass joint against a tilting of one of the two joint parts12,14upwards or downwards relative to the other of the two joint parts12,14during an adjustment between those two positions. This provides an additional guide, which ensures a uniform alignment between the two positions and prevents unintentional tilting.

By means of the two provided spring elements102,104, the eyeglass joint100can be adapted particularly well with respect to respective adjusting forces and automatic reset forces. For example, the spring element104can substantially define an snap effect in the use position and the spring element102can substantially define the snap effect into the stowage position. Accordingly, respective forces for moving from these respective positions can be specified at least partially independently of each other. In addition, the angular ranges in which the eyeglass joint100snaps into one or the other position can also be changed or specified.

For such a change, the geometries of the rolling portion22and the receiving portion24of the eyeglass joint100do not necessarily have to be changed; one can merely replace the spring elements102,104. This is also possible because no corresponding support surfaces are predetermined, which already substantially predetermine at which angle range the eyeglass joint100snaps into one or the other position, as it is for example specified with the cubic shape of the rolling portion22and the receiving portion24in the eyeglass joint10and the eyeglass joint50. In the eyeglass joint100, on the other hand, the rolling portion22and the receiving portion24are substantially rounded.

The schematic perspective view ofFIG.14shows a fourth embodiment of the eyeglass joint, which has been assigned the reference number150. The eyeglass joint150is formed similar to the eyeglass joint100, in particular, two spring elements102,104are provided here as well. These two spring elements102,104can be seen especially clearly in the schematic top views of the eyeglass joint150according toFIG.16andFIG.17. The use position of the eyeglass joint150is shown inFIG.14andFIG.16, while the stowage position of the eyeglass joint150is shown in the schematic perspective view according toFIG.15andFIG.17.

The eyeglass joint150can also be understood as a simplified version of the eyeglass joint100. Here, there is no tapering on the sides facing away from the contact surfaces between the two joint parts12,14. Similarly, there are no alternating elevations in the receiving portion24or in the rolling portion22. In addition, a torus-shaped indentation is provided for holding the spring element104in the recess106. Thus, the two joint parts12,14of the eyeglass joint150can be manufactured particularly cost-effectively.

In order to make the respective eyeglass joints10,50,100,150particularly wear-resistant, they can be provided with an additional sliding layer in the area of the respective contact surfaces, i.e. in particular in the rolling portion22and in the receiving portion24. This sliding layer can be formed, for example, by an epoxy resin, whereby a friction wear of the two joint parts12,14can be particularly minimized. Alternatively, or additionally, a lubricant can for example be provided between the two joint parts12,14, for example Teflon powder. Alternatively, or additionally, the two joint parts12,14can also be provided with a permanent Teflon layer.

Due to the fact that the eyeglass joints10,50,150and200can be assembled and disassembled particularly easily, they can also be part of a joint set and/or eyeglass frame sets. Thus, several different joint parts12,14and/or several different spring elements16,102,104can be provided. A home user can then configure and assemble a corresponding eyeglass joint according to his personal requirements. Similarly, for example, the rim and/or the eyeglass temple can be replaced according to different requirements. At the same time, the eyeglass joints10,50,100,150also allow an easy replacement and/or repair of individual parts as well.

Due to the fact that the two joint parts12,14are only held against each other by respective spring elements16or102and104, there is no rigid axis of rotation for a corresponding eyeglass joint. Instead, the two joint parts12,14can adjust relative to each other by both a rotary and a translational movement. In particular, an adjustment between the stowage position and the use position can be carried out by a combined sliding and rolling.

Respective manufacturing tolerances can be particularly large, especially in the area of the rolling portion22and the receiving portion24. A compression of the two joint parts12,14by means of the spring element16or102and104, automatically results in a tolerance compensation and the two joint parts12,14are held together with a minimal gap in every position. The eyeglass joint10,50,100,150has an integral tolerance compensation, which makes it particularly cost-effective. Corresponding manufacturing tolerances can be significant. In particular, due to deviations during manufacturing, a quick getting caught and/or blocking of the eyeglass joint10,50,100,150is not as likely as it is in the case of conventional joints. In addition, a corresponding joint does not detach even with repeated adjustment and/or must be readjusted by an optician, as is the case for example with a screwed eyeglass hinge. In particular, the eyeglass joints10,50,100,150are not permanently deformed by overloads and/or overstretching and/or over-compressing, and do not necessarily require maintenance after such a load.

The eyeglass joints10,50,100,150are symmetrically formed with respect to their upward direction, which is advantageous for manufacturing.

FIG.18,FIG.19andFIG.20each show a schematic perspective view of eyeglass joint50according toFIG.5. Here, various positions are shown, which the eyeglass joint50should not normally take during an adjustment between its stowage position and its use position, and which in conventional eyeglass joints quickly lead to damage and/or permanent deformation. However, the eyeglass joint50can accommodate such joint positions and the loads associated with them without being damaged. Such joint positions can also be taken by the eyeglass joints10,100and150without damage.

FIG.18shows the eyeglass joint50in an over-compressed position. The two joint parts12,14have been moved beyond the stowage position towards each other in the direction of the arrows62, wherein this movement was still carried out in the movement plane between the stowage position and the use position. Such over-compressing can take place, for example, by pressing on a pair of glasses hooked on to a shirt. As can be seen, in this case the two joint parts12,14roll on each other at the stop28, while the respective straight surfaces36move away from each other. The spring element16will continue to be in contact with the undercuts54and is thus stretched further compared to the stowage position. This creates an additional resetting force, which automatically adjusts the eyeglass joint50back into the stowage position after termination of the compressing of the glasses.

Since no axle pin is present and the spring element16is designed to accommodate such an additional stretch without damage, the eyeglass joint50is not damaged and/or permanently deformed. Instead, the eyeglass joint50automatically readjusts itself based on the straight surfaces36due to the joint parts12,14being tensioned against each other by the spring element16. Since the two joint parts12,14roll at the stop28and no portion of the joint parts12,14is subjected to inadmissible loading, such an improper load can easily be absorbed by the eyeglass joint50.

FIG.19shows the eyeglass joint50in an overstretched position. The two joint parts12,14have been moved away from each other in the direction of the arrows64beyond the use position, wherein this movement was still carried out in the movement plane between the stowage position and the use position. Such an overstretching can occur, for example, if the wearer lays his head sideways on a pillow while wearing the glasses. As can be seen, in this case the two joint parts12,14roll on each other at the additional stop52, while the respective straight surfaces36withdraw from each other. In particular, a wedge-shaped portion66of the joint part12slides on a corresponding recess68of the joint part14formed at the stop52. The spring element16will continue to be in contact with the bottom of the grooves34and is thus stretched further compared to the stowage position. This creates an additional resetting force, which automatically adjusts the eyeglass joint50back into the use position after termination of the forces causing the overstretching. Accordingly, the eyeglass joint50is also protected against damage by overstretching and is easy to handle since no maintenance is required after such an improper load.

If the eyeglass joint50is overstretched to such an extent that the wedge-shaped portion66completely slides out of the corresponding recess68, there is also an additional relief of the eyeglass joint50. In this case, the joint part12can jump off the joint part14, so to speak. Thus, the spring element is stretched less from this point forward, so that both the load on the joint parts12,14, in particular the thin-walled portion of the joint part14of the stop50facing away from the groove34, as well as that on the spring element16itself decreases. Such a state can also be understood as a partially dissolved joint connection, since upon further overstretching, the two joint parts12,14are substantially no longer in contact at the rolling portion22and the receiving portion24, and substantially no longer roll and/or slide on each other at a further overstretch, either.

Thus, it is possible to open the eyeglass joint50so far until the respective outer sides of the two joint parts12,14facing away from the groove34are at least partially in contact with each other, without damage. Depending on the preload of the spring element16and geometries of the joint parts12,14it may then be necessary to manually reconnect the partially detached joint connection. This can be done by turning back one of the two joint parts12,14in the direction of the use position, wherein the wedge-shaped portion66is threaded into the corresponding recess68. Even after that, the eyeglass joint50automatically readjusts itself. Accordingly, this partial manual connection can also be done intuitively by an eyeglass owner without the help of an optician, tool and/or additional training.

FIG.20shows the eyeglass joint50in a use position rotated upwards out of the movement plane. Here, the two joint parts12,14have been moved upwards in the direction of the arrows70from the movement plane, which can be defined by a direct connection between the stowage position and the use position or a pivoting movement between these positions. Such a bending can for example occur as a consequence of an accidental load on a pair of glasses placed on a table in the use position.

As can be seen, in this case, the two joint parts12,14roll on each other at the top edge, while the respective straight surfaces36again withdraw from each other. The spring element16will continue to be in contact with the bottom of the grooves34and is thus stretched further compared to the use position. This creates an additional resetting force, which automatically adjusts the eyeglass joint50back into the use position after termination of the forces causing the bending. Accordingly, the eyeglass joint50is also protected against damage by bending out of the movement plane and is easy to handle since no maintenance is required after such an improper load.

Such bending can also be done in combination with a previously described overstretching and over-compressing, without damaging the eyeglass joint50. Similarly, alternatively or in addition, a pulling apart of the two joint parts12,14and/or a rotation of respective joint parts12,14around their longitudinal axis, which can be predetermined by a main extension direction and/or extend in the movement plane, can be carried out without damaging the eyeglass joint50. In all the cases, the spring element16can be further stretched, so that a reset force causes an automatic return to an initial position in the movement plane and in a correct alignment of the two joint parts12,14to each other, in particular in the stowage position or the use position.

Of course, analogously to the eyeglass joint50, the other embodiments (glasses joint10,100,150) with their respective joint parts12,14can also be overstretched, over-compressed, bent, pulled apart and/or rotated without damaging them. In particular, the joint parts12,14can automatically return to their initial position.

FIG.21shows a schematic perspective view of a further embodiment of an eyeglass joint200. The eyeglass joint200has a functionality and construction which is basically similar to the eyeglass joints10,50and100. Respective features of these embodiments, such as providing several spring elements, can also be provided in the embodiment of the eyeglass joint200. In contrast to the previously shown eyeglass joints10,50and100, the respective cone-shaped and/or hook-shaped retaining elements218of the eyeglass joint200do not substantially extend in the movement plane and a plane defined by the ring shape of the respective spring element16,102,104does not extend orthogonally to the movement plane, either. Instead, the respective cone-shaped and/or hook-shaped holding elements218extend slanted, in the present case substantially orthogonally, to the movement plane of the eyeglass joint218and a plane defined by the ring shape of the spring element216of the eyeglass joint200extends substantially parallel to the movement plane, in the present case in the movement plane.

Due to this alignment of the retaining elements218, the eyeglass joint200can be particularly flat in an upward direction, which is illustrated by the double arrow220inFIG.21andFIG.22and which corresponds to an upward direction when glasses with the eyeglass joint200are worn. The assembly space the spring element requires in the upward direction, no longer corresponds to a double radius of the loop formed by the spring element around the retaining element218, but substantially only the diameter of the annular spring element216itself. Accordingly, the eyeglass joint200can be formed flatter in this direction.

As can also be seen particularly well inFIG.21, the retaining elements218are open in opposite directions for threading the spring element216. For example, the spring element216can only be threaded from the bottom onto the holding element218shown on the left inFIG.21, and it can only be threaded from the top onto the holding element218shown on the right. In the respective other direction, on the other hand, the respective joint part, which is formed integrally with the respective holding element218, forms a stop. This reliably prevents accidental slipping or stripping of the spring element218in the flat design of the eyeglass joint200, for example when the glasses are put on or taken off. As a result, the eyeglass joint200cannot unintentionally be disassembled.

The movement plane of the eyeglass joint200can easily be seen by comparingFIG.21withFIG.22where it is represented by the dotted line222.FIG.21shows the eyeglass joint200in the use position, whileFIG.22shows the eyeglass joint200in its stowage position in a schematic perspective view, wherein a movement between these two positions defines the movement plane. Here, the movement plane extends orthogonally to the upward direction illustrated by the arrow220. In particular, the movement plane lies in a plane formed by the ring shape of the spring element216and vice versa.

FIG.23illustrates, for all eyeglass joints10,50,100and200shown in the other figures, in a schematic perspective view how an eyeglass temple300of an eyeglass frame302can be moved relative to the rim304of the eyeglass frame302without damaging the respective eyeglass joint. One of the two eyeglass temples300is shown in the stowage position. The other eyeglass temple300is shown in the use position, and with it an arrow306, which shows a possible deflection from this position. Furthermore, exemplary positions of this eyeglass temple300are shown, in which the eyeglass joint is not damaged, and the eyeglass temple306furthermore automatically returns to the use position.

FIG.23furthermore illustrates a sliding layer or sliding piece308, which forms a receiving portion of the eyeglass joint shown therein. For this purpose, the sliding layer or sliding piece308has a different thickness in different portions and forms a three-dimensionally shaped surface, which is independent of the shape of a surface on which the sliding layer308is applied. In the present case, the sliding layer308is formed, for example, as a plastic part. The sliding layer308can also be regarded as an intermediate part between the two joint parts. The sliding layer308is glued to the rest of the eyeglass temple300, is particularly abrasion-resistant and slides particularly well on the corresponding rolling portion of the rim304. As a result, the glasses shown can be adjusted particularly easily between the stowage position and the use position. In the case of wear of the sliding layer308, it can also be replaced without necessitating a replacement of the entire eyeglass temple300.

The sliding layer308can for example also not be massively formed, as in the present case, but as a thin sleeve-shaped element, which can easily be attached to a receiving portion or rolling portion. In this case, the sliding layer308can also be referred to as a sliding sleeve. The sliding layer308may also be formed as a thin layer with an substantially consistent thickness, whose shape then corresponds to the shape of the underlying joint part, in particular a receiving portion or rolling portion formed thereon.

LIST OF REFERENCE NUMBERS

10eyeglass joint12first joint part14second joint part16spring element18retaining element20undercut22rolling portion24receiving portion26arrow28stop30arrow32portion34groove36straight surface50eyeglass joint52stop54undercut56middle gap58dotted line60dotted line62arrow64arrow66wedge-shaped portion68recess70arrow100eyeglass joint102spring element104spring element106recess108indentation110stop112portion114support surfaces200eyeglass joint216spring element218retaining element220double arrow222dotted lines300eyeglass temple302eyeglass frame304rim306arrow308sliding layer