Anti-rotation axis

Abstract

Locking mechanism for a wheel unit, preferably for a stroller, comprising a wheel axle with a circumferential groove, wherein a locking section, in particular a recess, is provided in the groove, and a fastening element comprising a first engagement section, wherein the first engagement section is designed to engage in the groove to fix the wheel axle in the longitudinal direction, and is further designed to cooperate with the locking section, in particular to engage in the recess, to block rotation of the wheel axle about the longitudinal direction, wherein preferably rotation of the wheel axle about the longitudinal direction is possible when the first engagement section engages in the groove, but does not cooperate with the locking section, in particular when it does not engage in the recess.

Description

[0001] The invention relates to a locking mechanism for a wheel axle, in particular for the wheels of prams.

[0002] Modern strollers often have removable wheels to make them easier to store and more compact. These wheels are typically mounted on a wheel bearing, allowing them to rotate around an axle. Attaching and / or removing the wheel is usually done by inserting the axle, along with the wheel, into a corresponding opening in the stroller. This opening contains a locking mechanism that prevents the axle from moving lengthwise relative to the stroller and thus from slipping out again.

[0003] During normal operation of the stroller, the wheel usually rotates around the wheel axle by means of the wheel bearing, while the wheel axle does not rotate relative to the stroller.

[0004] However, if the stroller becomes heavily soiled or iced over, the wheel's rotation around the axle can be blocked by the wheel bearing. In these cases, the axle and wheel may rotate within the stroller's locking mechanism. This leads to unwanted friction within the stroller, particularly against the locking mechanism, which can cause faster wear of the components and, in the worst-case scenario, lead to the wheel falling out.

[0005] It is therefore an object of the present invention to provide a locking mechanism that increases safety and minimizes wear and tear.

[0006] The problem is solved by a locking mechanism according to claim 1.

[0007] In particular, the problem is solved by a locking mechanism for a wheel unit, preferably for a stroller, comprising a wheel axle with a circumferential groove, wherein a locking section, in particular a recess, is provided in the groove, and a fastening element comprising a first engagement section, wherein the first engagement section is designed to engage in the groove to fix the wheel axle in the longitudinal direction, and is further designed to cooperate with the blocking section, in particular to engage in the recess to block rotation of the wheel axle about the longitudinal direction, wherein preferably rotation of the wheel axle about the longitudinal direction is possible when the first engagement section engages in the groove but does not cooperate with the blocking section (in particular when the first engagement section engages in the groove but not in the recess).

[0008] Unless otherwise stated, the following directional specifications refer to cylindrical coordinates defined by the wheel axle during normal operation. The longitudinal direction therefore corresponds to the direction of extension of the wheel axle, which is at least substantially cylindrical. The radial direction extends perpendicularly outwards in every direction, and the circumferential direction corresponds to the movement on the (or a) cylindrical surface.

[0009] A fundamental concept of the invention is that the first engagement section is initially designed to engage in the groove oriented in the direction of rotation. This restricts the movement of the wheel axle relative to the stroller in the longitudinal direction of the wheel axle, particularly away from the stroller, since the corresponding movement is blocked by the first engagement section. In this state, however, rotation of the wheel axle about the longitudinal direction can preferably still occur, since the first engagement section can slide along the bottom of the groove in the circumferential direction as long as it is not opposite the blocking section, in particular the recess.

[0010] In addition, the first engagement section can block rotation of the wheel axis about the longitudinal direction when it interacts with a blocking section arranged in the groove, in particular when it engages in a recess arranged in the groove, preferably at least partially at the bottom of the groove.

[0011] The blocking section can be designed as a depression or as a protrusion.

[0012] The projection can be formed on the bottom or on a side wall of the groove, but it does not have to extend over the entire circumference of the wheel axle. Accordingly, the first engagement section and the locking section can move radially or axially relative to each other to engage. For example, in a specific case, the projection can be formed on the bottom of the groove, while the first engagement section can have a (corresponding) recess, e.g., in the contact surface described below. The projection can be radially higher than the bottom of the groove and may optionally have flanks acting as cams, which push the first engagement section outwards until the projection and recess are precisely opposite each other and engage, thus preventing further rotation of the wheel axle.

[0013] The recess, which can be formed, for example, by a bore, is a cutout that lies deeper in the radial direction than the bottom of the groove, but does not extend over the entire circumference of the wheel axle. This allows the first engagement section to engage in the recess, thereby blocking it in the circumferential direction and preventing further rotation of the wheel axle.

[0014] In one embodiment, the recess can have a circular cross-section. Additionally or alternatively, the extent of the recess in the longitudinal direction can be slightly larger than the corresponding extent of the groove. In particular, the recess can be designed as a circular bore with a diameter slightly larger than the longitudinal extent of the groove, the bore preferably being arranged centrally to the groove in the longitudinal direction.

[0015] It is therefore possible to block a displacement of the wheel axle in two orthogonal directions (in particular the displacement along the longitudinal direction and the rotation in the circumferential direction) with the fastening element when it interacts with the blocking section, in particular when it engages in the recess.

[0016] According to a preferred embodiment, the locking mechanism comprises an elastic element which preloads the fastening element in a direction, preferably radial, with respect to the wheel axis, in order to force the first engagement section to interact with the blocking section, in particular to engage in the recess, when the blocking section, in particular the recess, and the first engagement section are aligned with each other.

[0017] The elastic element simplifies wheel assembly for the user. Because the engagement section is pre-tensioned by the elastic element, particularly radially inwards, it can automatically interact with the locking section, specifically engaging in the recess as soon as it is aligned with it circumferentially. Furthermore, the elastic element (for example, a coil or leaf spring) makes it more difficult for the first engagement section to detach from the locking section, especially from the first engagement section jumping out of the recess and / or groove, for example, due to vibrations.

[0018] The elastic element can have a first end that rests against the fastening element. For example, if the elastic element is designed as a coil spring, the first end can engage in a corresponding recess on the fastening element, or the fastening element can have a projection that, in turn, engages with the first end of the coil spring. Furthermore, the elastic element can have a second end designed to interact with a support, such as that of a stroller. This interaction with the support can also be achieved, for example, by engaging with a projection or recess.

[0019] According to a further preferred embodiment, the fastening element has an actuating section and a connecting section, wherein the connecting section connects the actuating section to the first engagement section, so that actuation of the actuating section forces the first engagement section to move away from the wheel axis in a radial direction, preferably to release the first engagement section from the locking section, in particular to move it out of the recess, and / or to move the first engagement section completely out of the groove.

[0020] This allows the wheel axle to be removed from its bearing. In particular, the first engagement section can be moved from a first position, in which it interacts with the locking section, specifically engaging in the recess and thus preventing rotation of the wheel axle around an axis along the longitudinal direction and also preventing displacement along the longitudinal direction, to a second position, in which it engages in the groove and thus prevents displacement along the longitudinal direction, but allows rotation around the longitudinal axis.

[0021] For this purpose, the first engagement section is released from the blocking section by means of actuating the actuating section, in particular it is brought out of the recess, whereby it is not raised above the level of the outer surface of the wheel axle (and thus not out of the groove), and the wheel axle is rotated slightly around the longitudinal axis, so that the recess and engagement section are no longer opposite each other.

[0022] If the wheel needs to be completely removed, the actuating section can also be activated to fully remove the first engagement section from the groove. In this case, the wheel axle is no longer locked in its longitudinal direction and can be removed from the stroller.

[0023] Actuation of the actuating section can consist in particular of pushing or pulling the actuating section.

[0024] In a further preferred embodiment, the actuating section and the first engagement section can be arranged on (exactly) opposite sides of the wheel axle, and / or the actuating section and the first and / or second end of the elastic element can be arranged on (exactly) opposite sides of the wheel axle when the locking mechanism secures the wheel unit, in particular on the stroller.

[0025] In a preferred embodiment, the connecting section can partially encompass the wheel axle, for example by at least 120°, preferably by at least 150°, when the locking mechanism secures the wheel unit, particularly on a stroller. For this purpose, the connecting section can be designed as a (curved) arm. Preferably, the connecting section encompasses the wheel axle only on one side (however, in a further embodiment, the connecting section can also encompass the wheel axle on two sides, for example by means of a second arm). Preferably, an opening is located opposite the connecting section, which is dimensioned to position the wheel axle between the actuating section on the one hand and the first engagement section and / or elastic element on the other.

[0026] According to a further preferred embodiment, the first engagement section has a contact surface which can be brought into contact with the wheel axle at least partially, wherein preferably the first engagement section is concave in the area of ​​the contact surface.

[0027] The contact surface of the first engagement section is preferably shaped such that the first engagement section lies flat against the bottom of the groove when it engages in the groove, but does not interact with the blocking section, in particular does not engage in the recess.

[0028] This ensures a more even sliding of the first engagement section across the bottom of the groove, thereby reducing wear and preventing contaminants from entering the mechanism. Since the bottom of the groove is essentially the outer surface of a cylinder with a smaller diameter than the wheel axle, a concave, preferably circular segment-shaped, contact surface is particularly suitable.

[0029] According to a particularly preferred embodiment, the bottom of the depression is convexly shaped.

[0030] This results, particularly in the case of a concave design of the first intervention section, in a form-fitting connection of the bottom of the depression to the first intervention section, which also minimizes the accumulation of dirt.

[0031] According to a further preferred embodiment, the locking section comprises a second engagement section, wherein the second engagement section is configured to rest against the bottom of the groove when the first engagement section engages in the recess, and wherein the second engagement section is configured such that it cannot engage in the recess, preferably by being too large, in particular too wide.

[0032] By providing a second engagement section, a more robust overall design can be achieved. The second engagement section is preferably larger (more preferably wider) than the first engagement section in at least one direction, so that it cannot engage in the recess. This effectively prevents longitudinal displacement of the wheel axle. Simultaneously, the first engagement section can be designed as a projection on the second engagement section, allowing the penetration depth of the first engagement section into the recess to be adjusted by its overhang.

[0033] By ensuring that the second engagement section rests on the bottom of the groove, the penetration of dirt into the recess can be further hindered.

[0034] Embodiments of the invention are further explained below with reference to the figures. This shows Fig. 1 A view of a baby carriage, Fig. 2 A representation of the wheel with the wheel axle, Fig. 3 One opposite. Fig. 2. Representation of the wheel axle rotated around the longitudinal axis, Fig. 4 A view of the fastener, Fig. 5 Another view of the fastener, Fig. 6 A sectional view of the locking mechanism.

[0035] Fig. Figure 1 shows a front view of a stroller 1 with a wheel 2 (in particular a rear wheel) which is attached to a locking mechanism according to the present invention.

[0036] Fig. Figure 2 shows a view of a wheel 2, which is attached to a wheel axle 3 via a wheel bearing 5. The wheel 2 can rotate freely around the wheel axle 3 via the wheel bearing 5. Also shown is the groove 4, which runs along the circumference of the wheel axle 3. The recess 6 is also visible at the lower end of the groove 4.

[0037] Fig. 3 shows essentially the same configuration as Fig. 2, with the difference that the wheel axle 3 was rotated forward by approximately 90° about the longitudinal axis, so that the recess 6 is more clearly visible. In the illustrated embodiment, the recess corresponds to a circular bore.

[0038] Fig. Figure 4 shows the wheel 2 and the wheel axle 3, but also shows other elements of the locking mechanism. As can be seen, the fastening element 14 engages in the groove 4 by means of the first engagement section (not shown). As is clearly evident here, the fastening element 14 fixes the wheel axle 3 longitudinally. Lateral displacement of the wheel axle 3 is therefore not possible. Also shown is the elastic element 7, here in the form of a spring (a coil spring), which preloads the fastening element radially in order to force the first engagement section (not shown) towards the radial zero point (whereby the second end of the spring is intended to interact with an abutment not shown here, for example, of a stroller). The actuating section 10 can be seen at the upper end of the fastening element 14.

[0039] When the actuating section 10 is pressed, the fastening element 14 in this illustration moves downwards (against the preload direction of the elastic element 7), which allows the first engagement section (not shown) to move out of the recess (not shown) and / or the groove 4.

[0040] Fig. Figure 5 shows a side view of the fastening element 14. As can be seen, the connecting section 11 connects the actuating section 10 and the first engagement section 8. The first engagement section 8 also has a convex contact surface 12, which can be brought into contact with the bottom of the groove (not shown).

[0041] Also visible is the second engagement section 9, which in this example is wider than the first engagement section 8. This prevents the second engagement section 9 from penetrating into the recess (not shown). The elastic element 7 is fitted over a projection (base attachment) on the fastening element 14 and is thus connected to the fastening element 14.

[0042] The actuating section 10 is located directly opposite the elastic element 7, in particular its two ends, with respect to the wheel axle (not shown here). Furthermore, the actuating section 10 is located almost directly opposite the first engagement section with respect to the wheel axle (not shown here). The connecting section 11 is designed as an arm and partially encompasses the wheel axle (not shown here). Opposite the connecting section 11 is an opening that is sufficiently large to allow the fastening element 14 to be slid transversely onto the wheel axle 3, so that the wheel axle 3 is positioned between the actuating section 10 on the one hand and the first engagement section 8 and / or the elastic element 7 on the other.

[0043] Fig.Figure 6 shows a cross-section through the wheel axle 3 along the groove 4 to illustrate the function of the first engagement section 8 and the second engagement section 9. As can be seen, the second engagement section 9 rests on the bottom of the groove 13. Simultaneously, the first engagement section 8 engages in the recess 6, which is radially deeper than the bottom of the groove 13. This prevents rotation of the wheel axle 3 about its longitudinal axis (which here passes through the center of the wheel axle M and out of the plane shown).

[0044] It should be noted here that all parts described above, considered individually and in any combination, especially the details shown in the drawings, are claimed as essential to the invention. Modifications to this are familiar to those skilled in the art.

[0045] Furthermore, it is noted that the broadest possible scope of protection is sought. Therefore, the disclosure contained in the claims can also be specified by features that are described by further features (even if these further features are not necessarily included). It is explicitly noted that parentheses and the term "in particular" are intended to emphasize the optionality of features in the respective context (which does not imply that a feature is mandatory in the corresponding context without such indication). The term "element(s)" preferably denotes a coherent structure that may in turn be connected to at least one other structure (to form a potentially monolithic and / or internally immovable overall structure) or may be distinct from all other structures. Reference sign 1 stroller 2 wheel 3 wheel axle 4 groove 5 wheel bearings 6. Deepening / Blocking Section 7 Elastic element 8 First intervention phase 9 Second intervention phase 10 Actuation section 11 Connecting section 12 Contact area 13 Grooved floor 14 Fastening element M Center

Claims

[1] Locking mechanism for a wheel unit, preferably for a stroller, comprising a wheel axle with a circumferential groove, wherein a locking section, in particular a recess, is provided in the groove, and a fastening element comprising a first engagement section, wherein the first engagement section is designed to engage in the groove to fix the wheel axle in the longitudinal direction, and is further designed to cooperate with the locking section, in particular to engage in the recess, to block rotation of the wheel axle about the longitudinal direction, wherein preferably rotation of the wheel axle about the longitudinal direction is possible when the first engagement section engages in the groove, but does not cooperate with the locking section, in particular when it engages in the recess. [2] Locking mechanism according to claim 1, further comprising an elastic element which pre-tensions the fastening element in a, preferably radial, direction with respect to the wheel axis in order to force the first engagement section to interact with the blocking section, in particular to engage in the recess, when the recess and the first engagement section are aligned with each other. [3] Locking mechanism according to claim 2, wherein the elastic element is a coil spring or a leaf spring. [4] Locking mechanism according to one of the preceding claims, wherein the fastening element has an actuating section and a connecting section, wherein the connecting section connects the actuating section to the first engagement section, such that actuation of the actuating section forces the first engagement section to move away from the wheel axis in a radial direction, preferably to move the first engagement section completely out of the groove and / or the recess. [5] Locking mechanism according to one of the preceding claims, wherein the first engagement section has a contact surface which can be brought at least partially into contact with the wheel axle, wherein preferably the first engagement section is concave in the area of ​​the contact surface. [6] Locking mechanism according to one of the preceding claims, in particular according to claim 5 wherein the blocking section is designed as a recess with a bottom, wherein the bottom of the recess is preferably convex. [7] Locking mechanism according to one of the preceding claims, comprising a second engagement section, wherein the second engagement section is configured to rest against the bottom of the groove when the first engagement section engages in the recess, and wherein the second engagement section is configured such that it cannot engage in the recess, preferably by being too large, in particular too wide. [8] Stroller comprising a locking mechanism according to one of the preceding claims.

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