Nipple for spoked wheels, particularly for motorcycles

Abstract

A nipple for spoked wheels includes a head and a rod which are coaxial and through which a through-hole extends, a manoeuvring key in the head and an insert of plastics material which is inserted in the hole in order to engage in a screwing manner with friction with a threaded end of a spoke. The hole comprises a threaded portion which extends in the rod and a portion with an increased diameter which constitutes the seat for receiving the insert, the insert being formed with a tubular sleeve inserted in the seat at the side of the head and being blocked there by means of interference or adhesive bonding.

Claims

1. A nipple for spoked wheels, including a head and a rod which are coaxial and through which a through-hole extends coaxially, a manoeuvring key formed by a recess in the head and an insert of plastics material which is inserted in the hole in order to engage in a screwing manner with friction with a threaded end of a spoke, wherein the hole comprises a threaded portion which extends in the rod and a portion with an increased diameter between the threaded portion and the manoeuvring key, the portion with increased diameter which constitutes the seat for receiving the insert, the insert being formed with a tubular sleeve inserted in the seat at the side of the head and being blocked there by means of interference or adhesive bonding, wherein the recess in the head of the nipple forming the manoeuvring key includes a base which is intended to abut a tool which is configured to act with the manoeuvring key, the insert being arranged in a position which is axially more remote with respect to a top surface of the head than the base so as to prevent contact between the tool and the insert when the tool is inserted in the recess.

2. The nipple for spoked wheels according to claim 1, wherein the manoeuvring key is constructed in the form of a countersinking which is recessed in the head.

3. The nipple for spoked wheels according to claim 2, wherein the countersinking is of the type with a star or quad key.

4. The nipple for spoked wheels according to claim 1, wherein the seat is constructed from a section of the nipple corresponding to the base of a connection collet between the head and the rod.

5. The nipple for spoked wheels according to claim 2, wherein the seat extends in the nipple as far as the base of the countersinking.

6. The nipple for spoked wheels according to claim 1, wherein the nipple is produced from alloy steel having a resistance class greater than 6.

7. The nipple for spoked wheels according to claim 6, wherein the nipple is produced from alloy steel having a resistance class between 8 and 10.

8. The nipple for spoked wheels according to claim 1, wherein said nipple is suitable for motorcycling uses.

Description

(1) The characteristics and advantages of the nipple according to the invention will be better appreciated from the following detailed description of a preferred though non-limiting embodiment thereof which is illustrated by way of non-limiting example with reference to the appended drawings, in which:

(2) FIG. 1 is a cross-section of the nipple of this invention;

(3) FIG. 2 is a perspective view from the side of the head of the same nipple.

(4) In FIG. 1, there is generally designated 1 a nipple for spoked wheels which is particularly though not exclusively intended for wheels for motorcycles, preferably of the medium-to-heavy duty type, including a head 2 and a rod 3 which are both generally cylindrical and coaxial. A through-hole 4 extends axially through the head and rod and both preferably have a respective manoeuvring key 5, 6. Alternatively, only the head may have the manoeuvring key.

(5) Preferably, the manoeuvring key on the rod is constructed by a polygonal profile which is formed externally on the portion of the rod 3 which is distal with respect to the head.

(6) In one embodiment, the manoeuvring key on the head 5 is constructed by a counter-sinking 9 which is recessed in the head, at the distal side with respect to the rod and preferably shaped for TORX® (star) or QUADRIX™ (quad) keys.

(7) The head 2 is widened with respect to the diameter of the rod and is connected thereto by means of a frustoconical collet 7.

(8) In some embodiments, the hole 4 for the portion formed in the rod 3 is threaded with a thread 8 which is intended to receive in a screwing manner the threaded end portion of a spoke (not illustrated).

(9) Preferably, the thread 8 extends between an opening of the hole 4 and a section corresponding to the lower base of the collet 7. There is formed between the lower base of the collet 7 and the base of the counter-sinking 9 a portion 12 of increased diameter which defines a seat 10 with an increased diameter with respect to the diameter of the hole 4.

(10) An insert 11 is received and rotationally fixed in the seat 10. The insert 11 is formed with a tubular sleeve and it is preferably produced from plastics material. The outer diameter of tubular sleeve engages in the seat 10, while the inner diameter is such that it engages in a screwing manner with friction with the threaded end of a spoke when it is engaged in the hole of the nipple 1. The insert 11 is inserted in the seat 10 at the side of the manoeuvring key.

(11) In some embodiments, the insert 11 is received with slight interference, optionally helped by adhesive bonding.

(12) Preferably, the manoeuvring key 5 defines a base 5′, in correspondence of which e.g. there abuts the tool used to act on the key when it is urged in an axial direction on the manoeuvring key itself.

(13) According to a preferred embodiment, the insert 11 is arranged in an axially more remote position with respect to the top of the head than the spoke with respect to the base 5′ of the manoeuvring key.

(14) In this manner, the use of the tool is not impeded by the presence of the insert.

(15) More generally, this can be brought about by arranging the insert 11 in a position under the manoeuvring key with respect to the head 2 of the nipple.

(16) The rod and head of the nipple 1 are produced from alloy steel having a resistance class greater than 6 and preferably between 8 and 10 according to EN ISO 898-1.

(17) The invention thereby solves the problem set out and achieves a number of advantages, including better blocking to prevent accidental unscrewing on the spoke, a low weight and a great strength which ensure a more effective operation of the spoked wheel which is thereby also provided under tough conditions such as those which are generally found in heavy-duty motorcycles.