FIELD OF THE INVENTION

Generally, the present invention relates to vehicle frame structures and ar rangements thereof. Particularly, however not exclusively, the present in vention pertains to an arrangement for a bicycle frame and method of man ufacture thereof

BACKGROUND

Current bicycle rear frames, especially in the context of mountain bikes, have different rear frames wherein the rear triangle may take various forms and be coupled to the front frame via various link and suspension arrange ments. However, the rear triangle itself causes design limitations to the rear frame and usually yields limited space at the rear triangle. Increasing the size of the rear triangle leads to a heavier rear frame design, which is not preferred, since weight- strength optimization is a key design goal in high performance bike design.

The rear frames have to be designed for sufficient stiffness such that the axle point between the rear frame and the front frame has to endure fewer forces. Consequent axle points between the rear frame and the front frame are usually not stiff and may be prone to mechanical failure. Further, the rear frame triangles are bulky, which is logistically difficult, and in case of failure, the whole of rear frame has to be completely replaced for a new one.

Prior art publication US 6170845 B 1 discloses a bicycle frame for providing a damping capability, which frame has a rear part consisting of two chain stays that are pivotally connected at their proximal ends to the downtube of the bicycle frame. Other solutions for bicycle rear frames may be found in publications US 2018265164 AA, FR 3014076 A1 and NL 1031923 Cl representing the general state of art. SUMMARY OF THE INVENTION

The objective of the embodiments of the present invention is to at least al leviate one or more of the aforementioned drawbacks evident in the prior art arrangements particularly in the context of bicycle frame arrangements. The objective is generally achieved with an arrangement, bicycle frame and method in accordance with the present disclosure.

An advantage of the present invention is that it allows a bicycle frame struc- ture, which has a rear frame that has changeable sides.

Another advantage of the present invention is that it allows for the use of large bearings at the pivoting points between the front frame and the rear frame.

Another advantage of the present invention is that the solution yields a rear frame design with less material since a bridge of material between the two sides of a rear triangle is replaced by at least one connecting axle. The present invention is especially beneficial in mountain bike frames that has a pivoting joint or link system between the front frame and the rear frame.

In accordance with one aspect of the present invention an arrangement for a bicycle frame comprising

- two separate rear frame members,

- each rear frame member comprising at least one first connection point at the front of each rear frame member, and one other connec- tion point at the back of the rear frame member for a wheel,

- characterised in that the at least one first connection point comprising means for facilitating connection of the rear frame members via an axle, and

- said axle interlocking the rear frame members in a fixed position to each other.

According to an exemplary embodiment of the present invention the rear frame members are removably connected with the at least one axle. According to an exemplary embodiment of the present invention the at least one axle providing for interlocking of the rear frame members is coupled to the rear frame with mating connection.

According to an exemplary embodiment of the present invention at least one of the axles facilitates pivotable connection for a link system.

According to an exemplary embodiment of the present invention the ar- rangement comprises also second connection points and a second axle con nected to the second connection points.

According to an exemplary embodiment of the present invention the at least one of the axles connects the rear frame members to at least one pivoting point.

According to an exemplary embodiment of the present invention the first connection points are situated at the front part of the rear frame members. According to an exemplary embodiment of the present invention the back parts of the rear frame members are connected to the wheel.

According to an exemplary embodiment of the present invention each rear frame member has the shape of a closed triangle with one point of connec- tion at back of the rear frame member and two separate ends at the front of the rear frame member whereat at least one axle is connected.

In accordance with one aspect of the present invention a bicycle frame com prising an arrangement for a bicycle frame of claim 1 connected to a front frame via link j oints .

In accordance with one aspect of the present invention a method for manu facturing a bicycle rear frame member comprising - producing a closed triangle rear frame member forming a solid part,

- producing a connection point to the back of the rear frame member whereat the rear frame member may be connected to a wheel, - characterised in that producing a first connection point at the front of the rear frame member whereat the rear frame member may be con nected to an axle and via the axle to another rear frame member, and wherein the first connection point is such that it allows the rear frame member to be fixed in a position in relation to the axle.

In accordance with one aspect of the present invention a bicycle rear frame member manufactured by the method of claim 10. As briefly reviewed hereinbefore, the utility of the different aspects of the present invention arises from a plurality of issues depending on each partic ular embodiment.

The expression“bicycle” is herein used to refer to various wheel-based ve- hides for a number of users, which may be manually or motor-powered or a combination of the aforementioned, and it is meant to encompass also unicycles, tricycles quadracycles, and the like. In a broader sense, the ex pression may be also seen as to encompass motorbikes. The expression“a number of’ may herein refer to any positive integer start ing from one (1). The expression“a plurality of’ may refer to any positive integer starting from two (2), respectively.

The term“exemplary” refers herein to an example or example-like feature, not the sole or only preferable option.

Different embodiments of the present invention are also disclosed in the attached dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

Some exemplary embodiments of the present invention are reviewed more closely with reference to the attached drawings, wherein Fig. 1 depicts a partial cutaway view of an embodiment of the arrangement in accordance with the present invention,

Fig. 2 depicts an exploded view drawing of an embodiment of the arrange ment in accordance with the present invention, Figs. 3a and 3b depict aspects of the connection points of an embodiment of the arrangement in accordance with the present invention,

Fig. 4 depicts a cross-sectional view of an embodiment of the arrangement in accordance with the present invention,

Figs. 5a and 5b depict aspects of the rear frame members of an embodiment of the arrangement in accordance with the present invention,

Fig. 6 depicts a general view of the use of an embodiment of the arrange ment in accordance with the present invention in a bicycle frame arrange ment,

Fig. 7 depicts a flow diagram illustrating an embodiment of the method in accordance with the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS Fig. 1 depicts a partial cutaway view of an embodiment of the arrangement (100) in accordance with the present invention.

The embodiment of the arrangement comprises two rear frame members (102a, 102b), which are connected to each other at a first connection point (104a, 104b) and at a second connection point (106a, 106b) by the axles

(110, 112) arranged at the connection points (104a, 104b, 106a, 106b). The rear frame members (102a, 102b) further comprise third connection points (108a, 108b) for attaching a (rear) wheel and transmission components, such as a cogset, chain derailleur.

Optionally the two rear frame members (102a, 102b) of the arrangement comprise and are connected to each other at only a first connection point (104a, 104b) by a single axle (110). Therein the first connection point (104a, 104b) at each rear frame member (102a, 102b) and the axle (110) connect- ing them are sufficient to form a rear triangle without another axle connect ing the two rear frame members (102a, 102b). Alternatively, more than two connection points at the front of the rear frame members (102a, 102b) may be used for more than two axles to connect the rear frame members (102a, 102b) to each other and to pivoting arrangements, links or shock absorbers thereof.

At least one of the axles (110, 112) interlock the rear frame members (102a, 102b) in a position in relation to each other. Further the axles (110, 112) facilitate connection to a front frame (130) of a bicycle frame via link sys tem (124, 126). The axles (110, 112) rear frame members (102a, 102b) in a position in relation to each other but simultaneously they facilitate the ver tical or pivotal movement of the rear frame members such as that the move- ment of the rear frame members (102a, 102b) is also synchronized.

Fig. 2 depicts an exploded view drawing of an embodiment of the arrange ment (100) in accordance with the present invention As depicted in this embodiment, the axles (110, 112) may be removably connected to the rear frame members (102a, 102b). This connection may be facilitated by screw-like members (114a, 114b, 116a, 116b) as depicted. The removable connection and the screw-like fastening thereof allows for fast connection and removal of the rear frame members (102a, 102b), which is beneficial e.g. when either of the rear frame members (102a, 102b) gets damages and needs to be changed. Many such similar fastening means may be used. Further, the fastening means may be hand-operable such that no tools are required. Although not explicitly depicted, the fastening for attaching a (rear) wheel and transmission at the third connection points (108a, 108b) may be facili tated via locking skewers or the like.

Figs. 3a and 3b depict aspects of the connection points of an embodiment of the arrangement (100) in accordance with the present invention.

The first connection points (104a, 104b) and/or the second connection points (106a, 106b) may comprise grooves or other such structures for fa cilitating mating connection between at least one of the axles (110, 112) and the first connection points (104a, 104b) and/or the second connection points (106a, 106b). Such mating connection may be used to interlock the rear frame members (102a, 102b) to a position in relation to each other so that the rear frame members (102a, 102b) won’t move in relation to each other but only via the turning of the at least one (110, 112) in relation to a front frame (130) or link system therebetween to which the at least one axle (110, 112) is connected. Fig. 4 depicts a cross-sectional view of an embodiment of the arrangement (100) in accordance with the present invention.

The connection of the rear frame members (102a, 102b) at the correspond- ing connection points (106a, 106b) by the axle (112) and fastening screw like members (116a, 116b) is shown in detail. The axle (112) as well as the fastening screw-like members (116a, 116b) may be partly hollow for re duced weight. The function of the axle (112) is to connect the two rear frame members (102a, 102b) to each other such that the two rear members (102a, 102b) may be manufactured independently without any physical connection therebetween. The axle (112) interlocks the two rear frame members (102a, 102b) to each other and further carries forces induced to the rear frame members (102a, 102b) when in use such that the axle (112) (together with other axles and connection of the rear wheel) produce a bridge between the rear frame members (102a, 102b) closing the rear frame members (102a, 102b) via the axles into a rear triangle (excluding the seat tube).

As depicted, the axles (110, 112) may comprise bearing arrangements be tween axles (110, 112) and the links (124, 126), which links (124, 126) con- nect the rear frame members (102a, 102b) and axles (110, 112) to the front frame (130) of a bicycle. This way the connection between the links (124, 126) and the axles may be pivotable and the rear frame as a whole may pivot in relation to the front frame (130) of the bicycle. Figs. 5a and 5b depict aspects of the rear frame members of an embodiment of the arrangement (100) in accordance with the present invention.

The rear frame members (102a, 102b) are preferably essentially in the shape of a closed triangle. As depicted, the connection points (104a, 104b, 106a, 106b, 108a, 108b) needn’t form the end points of the vertices (118a, 118b,

120a, 120b, 122a, 122b) of the triangle. The essentially horizontal vertices (118a, 118b, 120a, 120b) of the rear frame members (102a, 102b) are sup ported by the essentially vertical vertices (122a, 122b). The essentially ver tical vertices (122a, 122b) are preferably close to the front end of the rear frame members (102a, 102b), i.e. close to the first connection (104a, 104b) points and second connection points (106a, 106b). However, in relation to the strength and material property requirements of the rear frame members (102a, 102b) also other arrangements of the vertices (118a, 118b, 120a, 120b, 122a, 122b) are possible.

The vertices of the rear frame members (102a, 102b) may be curvilinear as depicted or they may linear.

The connection points (104a, 104b, 106a, 106b) for the axles are preferably situated at the front part of the rear frame members (102a, 102b). The con nection points (108a, 108b) for the rear wheel and transmission arrange- ments thereof are preferably situated at the rear part of the rear frame mem bers.

Various materials may be used for manufacturing the rear frame members (102a, 102b). Some examples include carbon fibre and other such suitable composites, as well as aluminum, steel and various known alloys.

Fig. 6 depicts a general view of the use of an embodiment of the arrange ment (100) in accordance with the present invention in a bicycle frame ar rangement.

The rear frame members (102a, 102b) may be connected to a front frame (130) of a bicycle via the axles (110, 112) and optionally link arrangements facilitated between the axles and the links (124, 126). Typically also a sus pension is facilitated via a link, which suspension in this embodiment is facilitated by a shock absorber between a point of connection (link) at an axle (110, 112) or either or both of the rear frame members (102a, 102b) and another point of connection (link) at the front frame (130). Any of the points connection may be pivotable and situated in accordance with prefer ence and/or different requirements set for the design of the bicycle overall.

Fig. 7 depicts a flow diagram illustrating an embodiment of the method in accordance with the present invention.

At 702, referred to as the start-up the manufacturing machine parameters may be set in light of the preferred design, used materials, etc.

At 704, a triangular rear frame member is produced as a solid part. At 706, the triangular rear frame member is produced a connection point for a wheel preferably to the rear end of the rear frame member. The connection point may be directly manufactured with the rear frame member or ma chined afterward e.g. by drilling.

At 708, the triangular rear frame member is produced a connection point for a connecting axle preferably to the front end of the rear frame member. The connection point may be directly produced with the rear frame member or machined afterward e.g. by drilling. The connection point for an axle is preferably added with mating connection means that allow the rear frame member to be interlocked to an axle and in relation to the rotation of the axle. In some embodiments, more connection points for additional axles may be produced. A connection point for an axle may be further fitted with a housing for an axle.

The scope of the invention is determined by the attached claims together with the equivalents thereof. The skilled persons will again appreciate the fact that the disclosed embodiments were constructed for illustrative pur poses only, and the innovative fulcrum reviewed herein will cover further embodiments, embodiment combinations, variations and equivalents that better suit each particular use case of the invention.