TIP ATTACHMENT

Abstract

Tip attachment for a pole, in particular for a trekking pole, cross-country-skiing pole, Nordic-walking pole or downhill-skiing pole, having a plastic sleeve, which can be fastened at the lower, free end of a pole tube and, at an upper end, has an upwardly open hole for accommodating the lower, free end of the pole tube, and a tip insert is fastened in an opening at the lower end of the pole tube. The tip insert has a carrier element, which is releasably fastened in the opening by a drive-in thread provided on a retaining region in a substantially cylindrical region.

Description

TECHNICAL FIELD

The present invention relates to a tip attachment for a pole, in particular for a trekking pole, cross-country skiing pole. Nordic walking pole or alpine ski pole, and methods for assembling such a pole attachment and repairing such a tip attachment.

PRIOR ART

Trekking poles, cross-country skiing poles, Nordic walking poles or alpine ski poles have at the upper free end thereof a handle and at the lower free end thereof a tip or a rolling surface.

The tips are in this instance often in the form of separate plastics material elements at the lower end of which a (hard) metal tip is secured. Such tips are generally adhesively bonded in plastics material or pressed in in such a manner that they can no longer be removed without destroying the plastics material in which they are secured.

CN203329296U describes a pole tip which has an expansion nail and an expansion nail plastics material sleeve. The expansion nail is formed by means of a nail cap and a nail rod, wherein one end of the nail rod and the nail cap are fixed and the other end of the nail rod is introduced into the expansion nail plastics material sleeve and connected to the expansion nail plastics material sleeve. On the outer wall of the nail rod, on from a quarter to two-thirds of the overall length from an end which is secured to the nail cap to the nail rod, a conventional thread structure is formed. The nail rod is initially nailed into the expansion nail plastics material sleeve and then connected to the expansion nail plastics material sleeve in a threading method. The outer wall of a nail rod of an existing pole tip product is improved in such a manner that it has a semi-thread structure, the nail rod is first nailed during installation into the expansion nail plastics material sleeve and then screwed. Installation time is thereby saved and the working efficiency is improved; the pole tip is in the case of relatively long-term use not susceptible to loosening, is secure and durable. EP-A-2 896 438 describes a changing element which can be releasably secured to a free lower end of a pole tube, in particular for a trekking pole, cross-country skiing pole, Nordic walking pole or ski pole, having a tip element which at the lower end thereof has a tip, rolling surface or in the lower end of which a tip is introduced, and which has an axial blind hole which is open in an upward direction for receiving the free lower end of the pole tube. The tip element is characterized in that the tip element has in the upper edge thereof at least one axial slot and a circumferential, annular collar which at least partially engages round the tip element and which can be releasably secured to the tip element in the region of the upper edge in such a manner that at least one projection on the pole tube and/or a transverse pin which is supported in at least one hole of the pole tube transversely relative to the pole axis and in which at least one axial slot of the tip element is caught by the collar and the tip element is thereby secured at the free end of the pole tube.

KR20090099175 provides a pole which is provided with a tip module and which can prevent damage and abrasion of a tip by absorbing the impact acting on the tip. A pole which is provided with a tip module comprises a tube; and a tip module which is fitted to the front end of the tube. The tube has such a shape that the diameter becomes smaller from the center toward the base. The tip module comprises: a circular, pillar-like tip; a tip holder which covers the circumference of the tip; a damper which is arranged at the top on the tip and which absorbs the impact applied to the tip; a stopper which is connected to the tip holder and which carries the damper; and a basket holder which connects the tip holder and the tube so that the tip holder can be arranged on the base of the tube.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a tip for such applications which can be produced in a simple manner and in which it is also possible to replace individual elements which are worn.

The invention accordingly relates to a tip attachment according to claim 1 and methods for assembling or for repairing such an attachment.

Specifically, a tip attachment for a pole, in particular for a trekking pole, cross-country skiing pole, Nordic walking pole or alpine skiing pole is proposed, having a plastics material sleeve which can be secured to the lower free end of a pole tube and which has at an upper end an upwardly open hole for receiving the lower free end of the pole tube, and at the lower end of which a tip insert is secured in an opening.

In this instance, the proposed tip attachment is according to the invention characterized in that the tip insert has a carrier element which is releasably secured to a drive-in thread which is provided in a retention region (which in this instance in each case includes a pressing-in thread or is intended to be understood to be synonymous therewith, wherein pressing in or driving in is intended to be understood to be a purely axial movement into the cylindrical region of the opening) in a substantially cylindrical region in the opening.

It has surprisingly been found that a drive-in thread or pressing-in thread which is intended to be differentiated from a conventional thread since it has thread turns having different flank inclinations, although it is retained without material engagement and simply by means of non-positive-locking and/or positive-locking engagement in the plastics material sleeve, is retained sufficiently securely in the plastics material sleeve even for intensive use, but, on the other hand, when the tip is worn, can be removed again from the plastics material sleeve purely by means of rotation and without being destroyed and, for example, can be replaced.

Typically in this instance, the retention region is approximately from 5 to 30 mm, preferably from 10 to 20 mm long, and pressed or hammered into a substantially cylindrical region with an inner diameter which is slightly smaller prior to assembly than the outer diameter of the drive-in thread (pressing-in thread) completely without bonding agents.

A first preferred embodiment is characterized in that the retention region has at least one thread turn which extends around at least once (preferably at least two or at least three times) and the flat flank of which facing the upper end of the plastics material sleeve encloses with an axis of the tip attachment a smaller angle than the steep flank thereof facing away from the upper end of the plastics material sleeve.

The angle between the flat flank and the axis is preferably in the range from 5 to 60°, preferably in the range from 10 to 40°, particularly preferably in the range from 15 to 30° and the angle between the steep flank and the axis is in the range from 60 to 90°, preferably in the range from 70 to 85°, particularly preferably in the range from 75 to 85°.

The difference in the angles between the flat flank and the axis or the steep flank and the axis is preferably in the range from 20 to 60°, preferably in the range from 30 to 50°.

Such a tip insert may be characterized in that it has at the end thereof facing away from the plastics material sleeve a receiving opening for receiving a hard tip and has such a tip, wherein the tip is preferably a tip made of a (hard) metal or ceramic material which is secured in the receiving opening in the form of a blind hole, preferably pressed in and/or adhesively bonded.

The carrier element preferably has at the end thereof facing away from the plastics material sleeve a tip expansion which, with a step being formed in the direction toward the plastics material sleeve, is constructed in a tapering manner so that a substantially radially extending stop face is formed between the retention region and the tip expansion, wherein the tip expansion is preferably formed at the side facing away from the retention region as a conically convergent surface region.

The carrier element may, in the region thereof which is exposed in the assembled state of the plastics material sleeve, have means for engaging an assembly tool, in a particularly preferred manner in the form of engagement faces, preferably axially extending parallel engagement faces, but special faces are also conceivable so that replacement can be carried out only using permissible tools.

The retention region is further preferably at the free end thereof in the form of a tip without any thread, wherein this tip preferably has a conically converging tip region and a substantially cylindrical region which follows it in the direction toward the drive-in thread/pressing-in thread (typically having an axial length in the range from 2 to 6 mm, preferably from 2 to 4 mm). This leads to the retention region being able to be introduced during assembly first with this tip into the opening and then also being sufficiently guided so that it can be subsequently hammered or pressed in without tilting.

Another preferred embodiment is characterized in that the substantially cylindrical region has a smaller outer diameter than the highest protrusion of the thread turn of the drive-in thread/pressing-in thread, and in that the outer diameter of the substantially cylindrical region of the tip substantially corresponds to the inner diameter of the cylindrical region in the opening of the plastics material sleeve.

The highest protrusion of the thread turn of the drive-in thread/pressing-in thread typically has an outer diameter which is greater than the inner diameter of the cylindrical region in the opening of the plastics material sleeve, wherein the outer diameter of the thread turn is preferably at least 0.1 mm, preferably at least 0.5 mm, particularly preferably in the range from 0.1 to 2 mm or 0.1 to 1 mm greater than the inner diameter of the cylindrical region.

The plastics material sleeve may have around the opening a radially extending stop face, the outer diameter of which substantially corresponds to the outer diameter of a radial stop face of the carrier element.

The plastics material sleeve is typically produced from a thermoplastic plastics material, preferably in injected form, wherein it is particularly preferably a plastics material selected from the following group: polyethylene, polypropylene, polyamide, polyurethane, polycarbonate, where applicable with fillers and/or fiber reinforcement.

The carrier element of the tip attachment typically comprises a hard plastics material (for example, refractory thermoplastic material such as, for example, terephthalic-acid-based polyamide, where applicable in glass-fiber-reinforced form) or metal, preferably metal, in a particularly preferred manner stainless steel or surface-treated steel, for example, zinc-plated steel.

The present invention further relates to a method for assembling a tip attachment as described above, which is in particular characterized in that the plastics material sleeve is presented and subsequently the carrier element of the tip attachment, preferably with the tip already secured thereto, is hammered or pressed in an axial direction into the plastics material sleeve without using a bonding agent.

Subsequently or beforehand, the tip attachment may be secured to a pole tube.

The present invention further relates to a method for changing a tip in a tip attachment as described above which is in particular characterized in that the tip insert is unscrewed from the plastics material sleeve and a replacement tip is hammered or pressed into the plastics material sleeve.

Finally, the present invention relates to a pole, in particular trekking pole, cross-country skiing pole, Nordic walking pole or alpine skiing pole, having a tip attachment as described above.

Further embodiments are set out in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below with reference to the drawings which are intended to be explanatory and are not intended to be interpreted in a limiting manner. In the drawings:

FIG. 1 shows in a) a side view of a tip attachment according to the invention in the assembled state and in b) an axial section along A-A of the tip attachment according to a), in c) a perspective view obliquely from below and in d) a perspective view obliquely from above;

FIG. 2 shows in a) a schematic illustration of how such a tip attachment can be mounted, and in b) a schematic illustration of how with such a tip attachment the tip insert can be removed; and

FIG. 3 shows as a perspective view obliquely from below a carrier element for a tip insert.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a tip attachment 1 in the assembled state as different views. The pole tube 2 on which such a tip insert is typically placed, generally with an adhesive connection or press-fitting connection, is schematically illustrated in the side view according to FIG. 1a).

Such a tip attachment 1 has a plastics material sleeve 3 which at the very top has a conical upper region 5 which expands in a downward direction and then tapers in a step 26. This stop step 26 is generally provided so that a plate having a through-opening and an inner thread can be pushed on from below and screwed on, wherein the inner thread of such a plate then cooperates with the outer thread 4 of the plastics material attachment. In this instance, locking mechanisms of such a plate may further be provided, for example, resilient tongues or the like, in particular a system as disclosed, for example, in WO2016/173827.

Whilst the plastics material sleeve 3 has at the upper end an opening 6 for receiving a lower tube end 2, the through-opening 16 which can be seen in particular in FIG. 1b) has at the lower end a substantially cylindrical region 15. In this cylindrical region which is arranged in an externally conically converging lower region 7 of the plastics material sleeve, a tip insert 8 is secured. The tip insert 8 comprises a carrier element 9 in the front tip of which a tip element 10 made of hard metal or ceramic material is securely introduced. To this end, the tip insert 8 has in the carrier element 9 a receiving opening 13. In this receiving opening the tip 10 is generally pressed and/or adhesively bonded with a conically slightly converging retention region 11, typically by means of a combination of non-positive-locking connection and material engagement.

The tip insert 8 has a conical surface region 17 which is exposed in the assembled state and which merges in the smoothest manner possible into the foremost portion of the conically convergent region 7 of the plastics material sleeve. To this end, on the one hand, there is a stop face 33 on the plastics material sleeve around the lower opening 25 and, on the other hand, a stop face 29 on the carrier element 9. When the tip insert 8 is hammered in or pressed in (cf. further below), these stop faces come into contact and limit the penetration depth of the tip insert 8 into the plastics material sleeve 3. The carrier element 9 now has, as can be seen, for example, with reference to FIG. 2a), in the retention region 15 thereof which engages in the plastics material sleeve a drive-in thread 19 (or pressing-in thread). This drive-in thread 19 is pressed into the cylindrical region 15 in the plastics material sleeve, specifically hammered or pressed in an axial direction according to arrow 23.

This is carried out without using bonding agents or the like. This is particularly also readily possible since the carrier element 9 has in the foremost or uppermost region a tip 18 having a conically convergent region 32 which is also followed by a cylindrical region 31 before the drive-in thread 19. The cylindrical region 31 substantially has an outer diameter which corresponds to the inner diameter of the cylindrical opening 15 and for this reason the carrier element 9, when it is pushed with this region 31 into the opening 15, is already guided in the best possible manner and can subsequently be hammered or pressed in according to arrow 23 without any risk of becoming tilted or wedged in the plastics sleeve 3.

The drive-in thread 19 has in this instance, as can be seen in particular with reference to FIG. 3, a thread turn 22 which extends in this instance approximately three times around. The thread flank 20 which faces toward the tip 18 of the carrier element 9, that is to say, is directed in the pushing-in direction, is in this instance constructed to be flat, that is to say, it has a small angle with respect to the axis 28 of the attachment. In contrast, the opposing thread flank 21 which is directed in the removal direction is in the form of a steep thread flank, it has a large angle with respect to the axis 28, virtually or even at a right angle. It is thus ensured that the carrier element can be easily hammered in with the drive-in thread but is then after hammering well secured in a non-releasable manner via the locking on the steep thread flanks 21.

The significant advantage of the proposed solution is now also particularly that in this construction the tip insert 8 can be readily removed from the plastics material sleeve 3 without being destroyed and, for example, replaced or exchanged. This is illustrated schematically in FIG. 2b). The tip insert may, for example, be gripped by means of the face 17 or even via flat engagement surfaces which are specifically provided there for the purpose for tools and readily unscrewed from the plastics material sleeve 3 along the arrow 14 and may be replaced by a new tip. If there are no specific engagement faces, the tip insert can be retained and unscrewed with the assistance of a suitable tool (for example, a set of pliers).

LIST OF REFERENCE SIGNS

• • 1 Tip attachment
  • 2 Lower tube end (schematic)
  • 3 Plastics material sleeve
  • 4 Outer thread
  • 5 Upper region of 3
  • 6 Upper opening for 2
  • 7 Conically converging lower region of 3
  • 8 Tip insert
  • 9 Carrier element of 8
  • 10 Hard metal or ceramic tip
  • 11 Retention region of 10
  • 12 Tip of 10
  • 13 Receiving opening for 10 in 9, blind hole
  • 14 Retention region of 9
  • 15 Cylindrical region of the through-opening
  • 16 Through-opening in 3
  • 17 Conical surface region of the tip of 9
  • 18 Tip of 14
  • 19 Drive-in thread, pressing-in thread
  • 20 Flat thread flank
  • 21 Steep thread flank
  • 22 Thread turn of 19
  • 23 Hammering direction, pressing-in direction
  • 24 Unscrewing direction
  • 25 Lower opening for 9
  • 26 Stop step
  • 27 Tapering in 16
  • 28 Axis
  • 29 Stop face
  • 30 Tip expansion
  • 31 Cylindrical region of 18
  • 32 Conically converging region of 18
  • 33 Radial stop face around 25

Claims

1. A tip attachment for a pole, having a plastics material sleeve which can be secured to the lower free end of a pole tube and which has at an upper end an upwardly open hole for receiving the lower free end of the pole tube, and at the lower end of which a tip insert is secured in an opening, wherein the tip insert has a carrier element which is releasably secured to a drive-in thread which is provided in a retention region in a substantially cylindrical region in the opening.

2. The tip attachment as claimed in claim 1, wherein the retention region has at least one thread turn which extends around at least once and the flat flank of which facing the upper end of the plastics material sleeve encloses with an axis of the tip attachment a smaller angle than the steep flank thereof facing away from the upper end of the plastics material sleeve.

3. The tip attachment as claimed in claim 2, wherein the angle between the flat flank and the axis is in the range from 5 to 60°, and the angle between the steep flank and the axis is in the range from 60 to 90°, and/or in that the difference in the angles between the flat flank and the axis or the steep flank and the axis is in the range from 20 to 60°.

4. The tip attachment as claimed in claim 1, wherein the tip attachment has at the end thereof facing away from the plastics material sleeve a receiving opening for receiving a hard tip and such a tip.

5. The tip attachment as claimed in claim 1, wherein the carrier element has at the end thereof facing away from the plastics material sleeve a tip expansion which, with a step being formed in the direction toward the plastics material sleeve, is constructed in a tapering manner so that a substantially radially extending stop face is formed between the retention region and the tip expansion.

6. The tip attachment as claimed in claim 1, wherein the retention region is at the free end thereof in the form of a tip without any thread.

7. The tip attachment as claimed in claim 6, wherein this tip (18) has a conically converging tip region (32) and a substantially cylindrical region (31) which follows it in the direction toward the drive-in thread (19) and wherein the substantially cylindrical region has a smaller outer diameter than the highest protrusion of the thread turn of the drive-in thread, and wherein the outer diameter of the substantially cylindrical region of the tip substantially corresponds to the inner diameter of the cylindrical region in the opening of the plastics material sleeve.

8. The tip attachment as claimed in claim 1, wherein the highest protrusion of the thread turn of the drive-in thread typically has an outer diameter which is greater than the inner diameter of the cylindrical region in the opening of the plastics material sleeve.

9. The tip attachment as claimed in claim 1, wherein the plastics material sleeve has around the opening a radially extending stop face, the outer diameter of which substantially corresponds to the outer diameter of a radial stop face of the carrier element.

10. The tip attachment as claimed in claim 1, wherein the plastics material sleeve comprises a thermoplastic plastics material, and/or in that the carrier element of the tip attachment comprises plastics material or metal.

11. A method for assembling a tip attachment as claimed in claim 1, wherein the plastics material sleeve is presented and subsequently the carrier element of the tip attachment, is hammered or pressed in an axial direction into the plastics material sleeve without using a bonding agent.

12. The method as claimed in claim 11, wherein the tip attachment is secured to a pole tube subsequently or beforehand.

13. A method for changing a tip in a tip attachment as claimed in claim 1, wherein the tip insert is unscrewed from the plastics material sleeve and a replacement tip is hammered or pressed into the plastics material sleeve.

14. A trekking pole, cross-country skiing pole, Nordic walking pole or alpine ski pole, having an attachment according to claim 1.

15. A tip attachment as claimed in claim 1, wherein it is for a trekking pole, cross-country skiing pole, Nordic walking pole or alpine skiing pole

16. The tip attachment as claimed in claim 2, wherein the angle between the flat flank and the axis is in the range from 10 to 40°, or in the range from 15 to 30° and the angle between the steep flank and the axis is in the range from 70 to 85°, or in the range from 75 to 85° and/or in that the difference in the angles between the flat flank and the axis or the steep flank and the axis is in the range from 30 to 50°.

17. The tip attachment as claimed in claim 1, wherein the tip attachment has at the end thereof facing away from the plastics material sleeve a receiving opening for receiving a hard tip and such a tip, wherein the tip is a tip made of a metal, including hard metal, or ceramic material which is secured in the receiving opening in the form of a blind hole, pressed in and/or adhesively bonded.

18. The tip attachment as claimed in claim 1, wherein the carrier element has at the end thereof facing away from the plastics material sleeve a tip expansion which, with a step being formed in the direction toward the plastics material sleeve, is constructed in a tapering manner so that a substantially radially extending stop face is formed between the retention region and the tip expansion, wherein the tip expansion is formed at the side facing away from the retention region as a conically convergent surface region and/or in that the carrier element has, in the region thereof which is exposed in the assembled state of the plastics material sleeve, means for engaging an assembly tool in the form of axially extending parallel engagement faces.

19. The tip attachment as claimed in claim 1, wherein the retention region is at the free end thereof in the form of a tip without any thread, wherein this tip has a conically converging tip region and a substantially cylindrical region which follows it in the direction toward the drive-in thread.

20. The tip attachment as claimed in claim 1, wherein the highest protrusion of the thread turn of the drive-in thread has an outer diameter which is greater than the inner diameter of the cylindrical region in the opening of the plastics material sleeve, wherein the outer diameter of the thread turn is at least 0.1 mm, or at least 0.5 mm, or in the range from 0.1 to 2 mm or 0.1 to 1 mm greater than the inner diameter of the cylindrical region.

21. The tip attachment as claimed in claim 1, wherein the plastics material sleeve comprises a thermoplastic plastics material, in injected form, wherein it is a plastics material selected from the following group: polyethylene, polypropylene, polyamide, polyurethane, polycarbonate, where applicable with fillers and/or fiber reinforcement, and/or in that the carrier element of the tip attachment comprises steel, including stainless steel or surface-coated steel, or zinc-plated steel.

22. A method for assembling a tip attachment as claimed in claim 11, wherein the plastics material sleeve is presented and subsequently the carrier element of the tip attachment, with the tip already secured thereto, is hammered or pressed in an axial direction into the plastics material sleeve without using a bonding agent.