EP3731686A1 - Device for attaching interchangeable heels for shoes with two springs - Google Patents

Abstract

A device for attaching removable interchangeable heels for shoes. The invention concerns the use of a system for locking and unlocking interchangeable heels in order to change heels as desired, while keeping the same pair of shoes. The device comprises a base with tenon, called the housing (1), in which a flat locking spring (6) is located, and a mortise part (22) in which a second flat spring (24) is inserted. The mortise and tenon assembly is locked when the two flat springs (6; 24), having complementary shapes, come into contact and immobilise one another. The user can act on the tab (8) of the locking flat spring (6) in order to pivot same and unlock the heel. The flat spring (6) automatically returns to its initial position due to its elasticity, when the user releases it. The device of the invention is intended, in particular, for the production of shoes with interchangeable heels.

Description

 DEVICE FOR FIXING INTERCHANGEABLE HEELS

 FOR SHOES WITH TWO SPRINGS

The present invention relates to the field of shoes, and more particularly to shoes with heels. It aims to allow the interchangeability of heels to be able to easily and quickly vary heights, colors and heel shapes, according to the desire of the user, while keeping the same pair of shoes, thanks to a mechanism attached to the sole at the back of the shoe and in the heel.

 The invention relates to a device for fixing interchangeable removable heels for shoes with a simple and economical mechanism under the shoe, at the heel.

Many interchangeable heel systems are known. However, these mechanisms are most often complex, expensive, impractical and sometimes seem insubstantial.

 This device is an improvement of the patent application FR1770083 already filed by us.

Indeed, this new mechanism allows better resistance to an external force and therefore a better fixation of the heel on the shoe. Instead of a notch in the mortise part simply adapted to the lug of the locking spring and often machined in the same material as the rigid heel, we add a second spring complementary shape for a strong and elastic assembly. This second spring avoids a complete recovery of the lug of the flat locking spring, during a major impact or the application of a continuous external force. The deformation of the second spring in response to a force allows a verticalization of its arms and thus an improvement in the locking of the two springs together. The first device described in patent application FR1770083 can be unlocked more easily when a force of more than 350 is applied. Newton, because the lug against a rigid material can go up because of its slope. The specificity of this new patent is the double spring assembly which can be deformed and allows the maintenance of cohesion, when applying a force of 550 to 720 Newton, depending on the slope of the heel, knowing that 500 Newton is the minimum required for fixing heels on basic shoes.

US4805320 presents an embodiment with a flat spring, in a projecting portion under the shoe, and a notch in the heel. In addition to the lack of information about the shape of the flat spring and its attachment under the shoe, the notch in the heel has the same problem of slope and stiffness, when applying a large force. In addition, the heel is machined in one piece, which is very difficult to do industrially. Our new mechanism has an external mortise and fixed part after production. This mortise part is the same for all the heels, when it is fixed in the heels, and involves a lower cost of production since it suffices to produce heels of basic shapes in which we fix the mortise part of the mechanism.

FR1409019 has, on the one hand, a mechanism with a flexible arm. This mechanism does not allow automatic locking of the stud in the heel during the nesting, and requires an external tool to unlock the mechanism, which is much less convenient than the present invention. On the other hand, this mechanism does not assemble by sliding backwards on the fins but by a simple interlocking: only the pin blocks the assembly from top to bottom, which is much less solid than a transverse tenon-mortise assembly that blocks assembly in many more directions. FR1409019 has, on the other hand, a tongue mounted on a tenon, with an elastic bias. In addition to the lack of information about the elastic process and the method of manufacture, the mechanism still does not allow automatic locking of the nipple in the heel. In addition, the locking pin seems much too small to lock the assembly and due to the rotation of the tongue when lifted, it could even less unlock if it had a larger dimension.

Advantageously, the present invention comprises forms which allow the release by lifting of the tongue and a facilitation of industrial realization due to the assembly housing / flat spring and mortise piece / second flat spring / heel, in addition to a locking strength thanks to the two springs.

FR2907318, has a device with a flexible portion made under the shoe and accessible to the front of the heel. However, a disadvantage of this system is that the flexible portion for locking and unlocking the device is made directly on the base under the shoe, by cutting thereof. The necessity of pivoting movement when using the mechanism may eventually lead to a break in the fixed part which serves as an axis of rotation. Another disadvantage is that the user must maintain the accessible portion of the flexible blade, when placing the heel on the shoe, to raise the pin, which is impractical. Finally, the locking pin still does not allow true rotation due to its shape and vertical sides.

The present invention aims to solve the problems mentioned above, ie to be simpler, more economical, easily achievable industrially and especially stronger by proposing a new removable heel assembly system on the shoe thanks to a locking of two flat springs. The addition of a second flat spring in the notch of the mortise piece considerably improves the strength of the assembly.

The present invention consists in the use of an interchangeable heel locking and unlocking system, comprising a tenon base, which will be called casing in which there is a flat locking spring, also called a clip, as well as a mortise portion in which a second flat spring is inserted.

The tenon-mortise assembly is locked when the two flat springs, having complementary shapes, come into contact and lock.

 This elastic system is discreetly and easily accessible by the user, at one of the faces of the housing. The accessibility of the system at the level of the front face is preferred to ensure the aesthetics and practicality of the shoe. The user can act on the tongue of the flat locking spring to rotate and unlock the heel. The flat spring automatically resumes its initial position thanks to its elasticity, when the user releases it. The mechanism having two springs allows a better attachment of the heel on the shoe due to the adapted forms thereof and their elastic properties.

According to a particular embodiment:

- The case, in a rigid and solid material, can be either directly machined under the sole of the shoe or fixed to the first mounting by means of suitable fasteners, such as bolts or screws, for example, which is preferred from an economic point of view.

 It can be machined to allow precise sliding of the mortise piece, from back to front, along a guide path, such as fins and allow a mortise and tenon type connection with the mortise piece , having a role of tenon. The interlocking movement of the mortise piece on the housing is a transverse movement from back to front.

 It can be machined to hold the flat locking spring.

 This housing may have three openings: an opening before which is inserted the locking spring and through which is accessed, a lower opening through which the locking pin of the locking spring and an upper notch in which a locking elbow locking spring is blocked. These openings may be machined on other faces of the housing if the flat locking spring is positioned differently or of different shape.

The flat locking spring may be formed of a locking lug, an upper locking elbow to be wedged in the upper notch of the housing and a folded tongue allowing it to be grasped, on the outside of the mechanism .

Advantageously, the flat locking spring is blocked in the housing by means of a transversally fixed axis and thanks to a locking elbow, the level of its upper part, which allows its exact positioning in the case.

 The flat spring can be extended by a slightly bent tongue pulling it towards one of the faces of the housing, favorably forwards, to allow the user to access it.

 An angularly shaped stud, such as V-shaped, is formed by special folding of the flat spring and is intended to lock the system by engagement in a second flat spring complementary shape, fixed in the mortise part of the heel. This lug can protrude under the housing under the action of the elastic force of the spring in the rest position and can go up by the action of the finger of the user when he acts on the tongue outside the housing.

 The resistance of the flat spring must be less than the force applied by the user's finger to the tongue to allow movement.

Advantageously, the lug does not block the sliding of the housing in the mortise piece due to its particular inclination given by an obtuse angle and obtained by folding. This avoids the blockage of movement during the establishment of the mortise piece on the housing.

The mortise piece, also called female part, is adapted to fit on the housing and contain a notch.

It can be machined in such a way that it slides backwards and forwards on the casing thanks to slides and can fit into them without play, in a solid and stable way, thanks to a suitable machining. It can be fixed to the heel by means of suitable fasteners, such as screws, for example, which allows it to be identical for all machined heels or it can be machined directly in the heel.

 The locking in the end position is ensured by the presence of a suitable notch receiving the lug protruding under the housing. The adapted notch is achieved by a second flat spring folded and inserted into the notch of the mortise piece.

 Unlocking the mortise piece is achieved by acting on the end of the locking spring, accessible at one of the faces of the housing, allowing its withdrawal backwards.

The second flat spring is folded at least three times to have a recessed shape, such as M-shaped for example, and to be adapted complementary to the shape of the flat locking spring, to receive the ergot of the last. It can be folded two more times at its ends to create two blocking elbows for its exact positioning and to be locked in the notch of the mortise piece. Its elastic thrust and the fixing of the mortise piece on the heel allow it to lock in the final position.

According to a variant of the invention, the housing with the flat locking spring and the mortise piece with the M-shaped spring can also be placed elsewhere in the mechanism.

The mechanism can indeed work by fixing or machining the housing in the heel and fixing the mortise piece to the first shoe mounting or by machining it under the sole of the shoe.

 In all embodiments, the housing and the mortise piece can be attached to the elements (first shoe mounting and heel) by means of suitable fasteners, such as screws, for example.

The locking spring may also have a different shape by changing, for example, its V-shaped lug into an inverted M-shaped hollow shape and the M-shaped spring may also, for example, take an inverted V shape to to become the locking pin. The functions of the 2 springs can be exchanged easily.

 The shapes and characteristics of the various elements may also vary while meeting the technical constraints of the invention.

An additional advantage of this embodiment is the possibility of changing the first flat spring if it were to deteriorate or break, without the need to change the entire housing, this elastic system being the most important part of the mechanism and being present on the most expensive part of the shoe / heel assembly.

The present invention will be better understood by studying a particular embodiment taken by way of example, in no way limiting and illustrated by the appended drawings, in which:

 - Figure 1 is a perspective view of an embodiment having the housing assembly, mortise piece and heel (dashed).

- Figure 2 is a section of the mortise and tenon assembly locked, with the cut mortise piece. - Figure 3 is a sectional view of the locked assembly when it undergoes anterior force.

Figures 1 to 3 illustrate an embodiment of the present invention. Alternative embodiments may take place with regard to the shapes, dimensions, positioning of the elements and certain characteristics and functions of the elements.

The shoe is not represented in the different figures. The heel (10) is shown in dashed lines in FIG. 1. The mortise piece (22) is shown whole in FIG. 1 and cut in FIGS. 2 and 3.

 The attachment means on the shoes and the necessary holes of the housing (1) are not shown in the figures.

 The housing (1) can be fixed, on the one hand, to the first shoe mounting by means of fasteners such as screws and the mortise portion (22) can be fixed to the heel by means of fasteners such as screws.

The casing must be able to hold the flat spring (6) and be adapted to its size in order to prevent as much as possible unwanted movements.

 The front opening (3) allows the insertion of the flat spring (6) by compressing it during the assembly and the handling of the locking spring during its use.

The lower opening (4) allows the locking pin (9) to exit the housing (1) and the upper opening (21) allows to block a portion of the locking spring (7).

The housing may have a bore (5) on its left side and its right side to insert a rigid pin for locking the flat spring (6) in addition to the locking elbow upper (7), being inserted into the upper notch (21) of the housing.

The flat locking spring (6) was chosen because of its elastic properties and for its ease of production and implementation. Advantageously, it can be machined in one piece. Its shape can, however, vary in order to best meet the technical constraints of the device.

By way of nonlimiting example, it can be machined, as shown in Figure 2, of rounded shape with an upper locking elbow (7), a folded end for handling that will be called tab (8) and a lower V-shaped locking lug (9).

 The upper locking wedge (7) makes it possible to lock the spring (6) in the upper part (21) of the casing (1) as well as to help the correct positioning of the spring when inserted into the casing.

 The tongue (8) can exit the housing (1) through the front opening (3) and can be pushed upwards by the user, which compresses the spring (6), to unlock the device.

 The lower locking pin (9) must protrude from the housing (1) through the lower opening (4) when the spring is in the rest position. 11 is machined so as to snap into the spring M (24) of the mortise piece (22) of the heel (10), which allows to lock the assembly. It can go up in the housing, during the action up the user on the tongue (8), which compresses the spring (6). It is also machined so as to fit fully into the housing when the spring (6) is compressed.

The lug (9) can have any shape allowing a cohesion and blocking adapted. The resistance of the spring (6) is such that pressure exerted by the finger of the user allows to raise the lug (9) (lever arm action).

The mortise piece (22) fixed on the heel (10) is the removable part of the device. It can have many shapes and heights to be at best fixed in the heel. It is also machined so as to slide easily around the housing (1): the fins (2) of the housing can slide in slides of the mortise part (22) and the latter (22) is inserted without play on the housing (1), thanks to a machining provided for this purpose.

 The notch (23) of the mortise piece (22) of the heel (10) must be machined to receive the spring M (24).

The M-shaped spring (24) is a flat spring folded at least three times (25; 26; 26 ') to have a recessed shape (25) for receiving the locking pin (9) of the locking spring (6). The folding (26, 26 ') of the spring M must be adapted to the slopes of the locking pin (9) so that it locks there without play. The spring M (24) can also be folded twice more at its ends to create two blocking elbows (27; 27 ') allowing it to be locked in the notch (23) of the mortise piece (22) of the heel (10).

We will describe the operation of the device during the introduction of the heel, when applying a significant external force and change heel.

When sliding the mortise piece (22), and therefore the heel (10), forwardly on the housing (1), the lug (9) rises, without effort, in the housing (1) by compression of the flat spring (6). The lug (9) does not block the sliding of the housing (1) in the mortise piece (22) of the heel (10) due to its particular inclination given by an obtuse angle.

 The pin (9), thus retracted into the housing, no longer blocks the sliding of the mortise piece (22) and thus the heel (10) which can then continue its way until it fits completely on the housing (1). ).

When the lower opening (4) of the housing (1) comes opposite the notch (23) of the mortise piece (22) of the heel (10), by further movement, the lug (9) can then come out thanks to the elastic decompression of the flat spring (6). The lug (9) is then positioned in the spring M (24) of the notch (23) of the mortise piece (22), accompanied by an audible click by the user, which then locks the shoe assembly / heel (10) or housing (1) / mortise piece (22).

 The tongue (8) of the spring is then positioned downwards, which, in addition to the click, indicates to the user that the lug (9) is snapped into the heel.

 This assembly is solid and play-free. The mortise piece (22) of the heel (10) can remain firmly attached to the housing.

(1) of the boot by the elastic thrust of the flat spring (6) which pushes and wedges the lug (9) in the spring M (24), when at rest.

 The heel (10) can not move in all three directions. The sides of the case (1) and the fins

(2) strengthen the assembly, also blocking movement in all directions.

When the heel undergoes a significant external force, represented by the arrow in Figure 3, due, for example, to a jerk against a step or a jerk of stroke, this force will affect the mortise piece (22), the spring M (24) and the locking pin (9).

The antagonistic elastic action of the two springs will add the necessary strength to avoid the separation of the assembly.

 For example, as shown in FIG. 3, if an external anterior force were applied on the heel (10) and thus on the mortise piece (22), the locking pin (9) could be pushed to the rear, reassemble and involve unlocking the system.

 Nevertheless, thanks to its elasticity, the spring M (24) could deform and compress the angle alpha. This slight compression would imply a movement of the forward slope of the spring M (24) which would then become more vertical. This verticality would then block the thrust of the locking pin (9) which could not go up. A greater reaction force would thus further increase the locking of the lug (9) on the spring M (24). The addition of a second spring assembly thus involves an improvement in the lock during the daily use of the device.

In order to separate the heel (10) of the shoe and thus the mortise piece (22) of the housing (1), the user must push the tongue (8) of the flat spring (6) upwards, which compresses it and the pin (9) being thus raised, the user can slide the heel (10) rearwardly to remove it from the body of the shoe.

The housing (1) and the mortise piece (22) of Figure 2 are machined in a hard and dimensionally stable material. The flat spring (6) and the spring M (24) of Figure 2 are machined in any metal that meets the constraints. techniques. These materials must also be light so as not to make the shoe too heavy.

 The spring M (24) must be thinner than the locking spring (6) so that it can deform unlike the locking spring (6) which must remain as inert as possible.

According to another embodiment, the locking system can be reversed by a modification of the locking spring (6) so that it comprises a hollow portion, in the form of an inverted M for example, instead of the pin (9). ) V-shaped and by a modification of the spring M (24) so that it is in the form of inverted V, for example, and not M, to serve as lock pin, in turn.

 According to yet another embodiment, the housing (1) could be fixed in the heel (10) and the mortise piece (22) could be fixed under the shoe, modifying their shape appropriately.

The realization of the invention is therefore possible in different ways. We have chosen to exhibit, by way of example, the simplest and most advantageous realization.

 The present invention is not limited to the embodiment described and shown, given only by way of example but the skilled person will be able to make any variant within his mind.

The device according to the invention is particularly intended for the simple and inexpensive manufacture of a pair of shoes with interchangeable heels easy to use.

Claims

1. Device for fixing removable interchangeable heels for shoes, characterized in that it comprises:  a housing (1),  - a flat locking spring (6), locked in the housing (1), a removable heel (10),  - a mortise piece (22) also called female part, adapted to fit on the housing (1) and to contain a notch (23),  a second flat spring (24), locked in the notch (23) of the mortise piece (22), adapted in a complementary manner to the shape of the flat locking spring (6). 2. Device according to claim 1 characterized in that the housing (1) is fixed to the first mounting or machined under the sole of the shoe and the mortise piece (22) is fixed or machined in the heel (10). 3. Device according to claim 1, according to another embodiment, characterized in that the housing (1) is fixed or machined in the heel (10) and the mortise piece (22) is fixed to the first mounting or machined under the sole of the shoe. 4. Device according to any one of the preceding claims characterized in that the housing (1) and the mortise part (2) are fixed to the elements (first shoe and heel mounting) by means of suitable fasteners, such as only screws, for example. 5. Device according to any one of the preceding claims characterized in that the flat locking spring (6) is formed of a locking pin (9), an upper locking elbow (7) to be wedged in the notch (21) of the housing (1) and a folded tongue (8) allowing it to be grasped, outside the mechanism. 6. Device according to any one of the preceding claims, characterized in that the second flat spring (24) is a flat spring folded at least three times (25; 26; 26 ') to have a recessed shape (25), such as M-shaped for example, to receive the lug (9) of the locking spring (6). 7. Device according to any one of the preceding claims characterized in that the second spring (24) can be folded twice more at its ends to create two blocking elbows (27; 27 ') allowing it to be locked in the notch (23) of the mortise piece (22). 8. Device according to any one of claims 1 to 4, according to another embodiment, characterized in that the locking spring (6) comprises an inverted M-shaped hollow portion in place of a shaped spur. V (9) and in that the second spring (24) is inverted V-shaped and not an M, to serve as a locking pin. 9. Device according to any one of the preceding claims, characterized in that the interlocking movement of the mortise piece (22) on the housing (1) is a transverse movement from back to front. 10. Device according to any one of the preceding claims, characterized in that the lug (9) does not block the sliding of the housing (1) in the mortise part (22) due to its particular inclination given by an obtuse angle.