WO2010046230A1

WO2010046230A1 - Application device and method for lubricating a chain drive

Info

Publication number: WO2010046230A1
Application number: PCT/EP2009/063007
Authority: WO
Inventors: Jan Tabellion; Guntram Fleischhauer; Mohammad Karimi Tabatabai; Werner Koch; Michael Nägele
Original assignee: Schunk Kohlenstofftechnik Gmbh
Priority date: 2008-10-20
Filing date: 2009-10-07
Publication date: 2010-04-29
Also published as: DE102008052105A1

Abstract

The invention relates to an application device and to a method for lubricating a chain drive, wherein the application device comprises a disk which can be rotated, wherein the disk can be moved up against a chain of the chain drive, and a contact area which can be rolled by the chain, wherein at least the contact area is made of a solid lubricant which can be consumed and which can be applied to the chain.

Description

Application device and method for lubricating a chain drive

The invention relates to an application device and a method for lubricating a chain drive, wherein the application device comprises a rotatable disc, wherein the disc against a chain of the chain drive can be brought into abutment, and having a rollable with the chain Kontaktbereicht, wherein at least the contact area of a consumable Solid lubricant is formed, which is applicable to the chain.

Chain drives are known to require lubrication if wear of the chain drive is to be reduced. For lubrication regularly liquid or pasty lubricants, such as oils or fats are used, which allow a viscous film application on a chain, in particular on their roles and tabs and on gears of the chain drive for the purpose of improving sliding properties. The known liquid lubricants may also contain additives such as graphite, molybdenum sulfide, soft metals or polymer-based additives, which then adhere to the component pairings to be lubricated due to the bond in the lubricant base material. Derar- lubricants are regularly applied by means of dedicated application devices or manually to certain components of the chain drive. For example, in chain drives of bicycles, motorcycles or similar vehicles with an open chain drive, it is necessary to apply such a lubricant manually in certain maintenance intervals. In most cases, it makes sense to remove old lubricant residues containing abrasion and dirt. Especially open chain drives have the disadvantage that they are exposed to environmental influences, such as moisture and dirt particles. In particular, dirt particles can easily reach a chain drive and adhere there due to the viscous film deposition of the lubricant to the components of the chain drive. If the particles of dirt thus get between pairs of sliding surfaces of the chain drive, they have an abrasive effect on the corresponding surfaces, which contributes to increased wear of the chain drive, which conflicts with the original intention to use a lubricant. Therefore chains are known from the prior art, the rollers are sealed against inner plates by means of rubber seals, so that no dirt particles can get between the pin and rollers of the chain. However, these chains do not solve the problem of increased wear on exposed surfaces. Even the sole use of a solid lubricant does not initially seem appropriate since it then requires a continuous application of the solid lubricant, which does not affect the running properties of the chain drive, which can not be guaranteed by a manual application.

It is therefore an object of the invention to provide an application device and a method for lubricating a chain drive, with or with which an improved lubrication of a chain can be achieved.

This object is achieved with an application device having the features of claim 1 and with a method having the features of claim 19. The application device according to the invention for lubricating a chain drive comprises a rotatable disc, wherein the disc can be brought into abutment against a chain of the chain drive, and has a contact region which can be rolled with the chain, wherein at least the contact region is formed from a consumable solid lubricant which is applied to the chain Chain can be applied.

Since it is a solid lubricant, there is no application of a viscous film on the chain, whereby an adhesion of dirt particles with a abrasive effect can be effectively prevented. Also can be dispensed with a manual order of the solid lubricant, which considerably simplifies maintenance of the chain drive. The disc is a solid lubricant depot, which causes the lubrication of the chain drive over a relatively long period of time. A maintenance is only necessary if the disc is largely used up by the constant abrasion of the solid lubricant of the disc. It is also advantageous that the disc is rotatable so that the disc is engageable against the chain, causing rotation of the disc relative to tangential movement of the chain, without significantly affecting a function of the chain drive. The disc thus rolls with the chain in a contact area, which minimizes inhibition of chain movement due to frictional resistance.

A continuous rolling of the disc with the chain can be ensured in particular when the disc is profiled. Further, the profiled disc can be brought under a bias against the chain in engagement, which further promotes a stable rolling of the profiled disc.

It when the profiled disc has a gear-like geometry or is a gear is particularly advantageous. The profiled disc can then be used particularly well as a component of the chain drive and be adapted to constructive requirements of the chain. If the gear is a drive or an output gear, the gear can be integrated particularly well in the chain drive. In addition, no additional toothed wheel for forming the application device on the chain drive must then be engaged. The chain is then engaged with comparatively many teeth of the gear, whereby a particularly good application of solid lubricant to the chain can be achieved. The application device is then particularly easy to use on a chain drive of a bicycle or motorcycle.

Also, the gear can rest against a load strand or an empty strand of the chain. The gear is then available as a chain tensioner, in which case the gear preferably bears against the unloaded slack side. Further, it can be ensured that by means of the chain drive large forces can be transmitted, the gear itself is not exposed to any adverse stresses.

If the gear is a component of a chain tensioner of a derailleur, the gear can be integrated particularly well in the chain drive of a bicycle. The gear can then be easily replaced, moreover, it may have a comparatively small size. This allows a particularly cost-effective production of the gear possible. Furthermore, existing chain drives can be improved by replacing an existing gear of the chain tensioner with a gear designed as an application device.

In one embodiment, the application device may comprise two gears. For example, two gears of a chain tensioner may be formed on a derailleur as an application device, which advantageously bilateral lubrication of the chain tensioner passing chain can be effected.

Also, the contact region of the gear may be formed as a sprocket. Then only the ring gear must be formed from the solid lubricant, whereby a weight reduction of the gear as well a material savings with the associated cost advantages can be achieved. The hub can then be made from a relatively inexpensive material or by a low cost process.

If the hub is formed from a composite material or a plastic material, a weight saving is particularly easy to achieve. These materials can also enable a particularly simple production in which, for example, the ring gear is positively connected to a hub formed from composite material or plastic material by the formation of the hub by means of a shaping manufacturing process.

A composite material may be a carbon fiber reinforced plastic (CFRP). Carbon fiber reinforced plastic is particularly light and stable and, due to its material combination, can be connected to a solid lubricant body in a form-fitting or cohesive manner. Next carbon fiber reinforced plastic can be easily recognized as such by its external appearance, which discloses a special value of the material used for the application device and highlights their technical advantages over a conventional gear wheel.

In a further embodiment of this application device, the gear may be monolithic. The gear can then be made particularly simple, wherein the gear alone can form the application device. The reduced to a component application device can then be made particularly inexpensive, since it can be dispensed with further components.

Such a one-piece gear can form a radial bearing. On a use of, for example, bearing bushes for rotatably supporting the gear on an axis or on liquid lubricants For lubrication of the radial bearing can be omitted, since the gear itself is formed of solid lubricant.

The same may relate to an axial bearing of the gearwheel, if the gearwheel is to be guided axially, for example between plates of a chain tensioner. On the usual, located between gear and plates bearing discs can then be dispensed with. The gear can thus be in direct contact with an axially positioned holder.

It proves to be particularly advantageous with regard to the lubricating properties and the abrasion behavior as a prerequisite for the transfer of the lubricant to the chain when the solid lubricant is produced on the basis of graphite.

The advantageous lubricating and abrasion properties of graphite can also be achieved if the solid lubricant at least partially of graphite and incidentally from other admixtures, which allow adjustment of other desired properties of the solid lubricant. Thus, regardless of the exclusive or proportionate use of a graphite material to form the solid lubricant, other suitable additional substances may be used, such as molybdenum sulfide, tungsten disulfide. Polytetrafluoroethylene, tricalcium phosphate, calcium hydroxide, polyethylene, polyamide. In addition, the use of soft metals, such as lead, copper, antimony, conceivable. With regard to the formation of the solid lubricant based on graphite, admixtures of Teflon, copper, lead, antimony and molybdenum disulphide prove particularly advantageous.

Regardless of the selection of a suitable additive material, it is advantageous if the solid lubricant contains a wear-reducing additive, such as polytetrafluoroethylene. So can one possibly unwanted, excessive wear of the solid lubricant can be limited.

Likewise, it proves to be advantageous if the solid lubricant contains a corrosion-inhibiting additive with which the corrosion resistance of the chain drive, in particular in the area of engagement surfaces, can be improved.

In order to enable a sequential or temporally successive use of different material compositions of the solid lubricant, it proves to be advantageous if the solid lubricant has a layer structure, with different layers in their composition. In this context, applications are also conceivable in which the addition of an agent for solid lubricant proves to be advantageous, which can remove a possibly formed corrosion layer in a regular use interval of the chain drive.

In the method according to the invention for lubricating a chain drive, the chain drive comprising an application device with a rotatable disc, the disc is brought into contact with a chain of the chain drive, wherein a contact region of the disc rolls with the chain, wherein at least the contact region of a consumable solid lubricant is formed, which is applied to the chain.

The method can be used particularly advantageously when lubrication of a bicycle chain drive takes place.

Further advantageous embodiments of the method will become apparent from the feature descriptions of the dependent claims back to the device claim 1.

Hereinafter, a preferred embodiment of the invention will be explained in more detail with reference to the accompanying drawings. Show it:

1 shows an exploded view of a derailleur with a first embodiment of the application device;

FIG. 2 is an exploded view of a derailleur with a second embodiment of the application device; FIG.

Fig. 3 is a perspective view of a third embodiment of the application device.

Fig. 1 shows a derailleur 10 in an exploded view with a Schrägparallelogrammkäfig 1 1 and a chain tensioner 12. The Schräg- parallelogram cage 1 1 serves to guide a chain, not shown here along a slope of a pinion cassette also not shown here. The chain tensioner 12 is formed from an inner plate 13, an outer plate 14 and an intermediate arranged upper gear 15 and a device designed as a lower gear 16 applica- onsvorrichtung. The gears 15 and 16 are each mounted on screws 17 and 18 formed as axes. The screws 17 and 18 connect the inner plate 13 to the outer plate 14 so that the gears 15 and 16 are rotatably supported between the plates 13 and 14, respectively. In order to ensure a good rotation of the gears 15 and 16 - afford bearing bushes 19 and 20 are respectively provided, which are used in hubs 21 and 22 of the gears 15 and 16 respectively. The upper gear 15 is made of plastic and has in each case in axial contact surfaces 23 a coaxial groove 24 for receiving a sealing ring 25, wherein the sealing rings 25 are each covered by a disc 26 so that no contamination between bearing bush 19 and hub 21 can pass. Further, the discs 26 abut respectively on the plates 13 and 14, so that an axial guidance of the upper gear 15 is ensured. The lower gear 16 is made of substantially graphite and was made by press molding. Axial abutment surfaces 27 of the lower gear 16 each have coaxial recesses 28th for receiving discs 29, which also rest against the plates 13 and 14 and serve an axial guidance of the lower gear 16. The chain, not shown here passes through the chain tensioner 12 in the direction of the arrows 30, so that an inner side of the chain, which rolls with the drive and driven gear, not shown, rolls with the lower gear 16. Here, 16 solid lubricant of the lower gear 16 is applied to the lower side of the chain or on their contact surfaces with the lower gear. The solid lubricant allows lubrication of the contact surfaces of the chain with the input and / or output gear as well as the chain itself. Overall, the lower gear is

16 is formed in its outer shape like a conventional sprocket of a chain tensioner, so that it is allowed only a simple replacement of the conventional gear against the trained as an application device lower gear 16 to allow reliable lubrication of the chain by means of solid lubricant.

A second embodiment of an application device, which is designed as an upper gear 31 and a lower gear 32, can be seen in FIG. The toothed wheels 31 and 32 are arranged in a switching mechanism 33, which essentially corresponds to the switching mechanism 10 from FIG. 1 with regard to the illustrated components. The derailleur 33 dispenses with the bearing bushes 19 and 20, the sealing rings 25 and the discs 26 and 29 of the derailleur 10 of Fig. 1. This is made possible by the fact that the upper gear 31 and the lower gear 32 consist essentially of a graphite material , Axial abutment surfaces 34 and a hub 35 of the upper gear 31 and axial abutment surfaces 36 and a hub 37 of the lower gear 32 so get directly to the inner plate 13 and the outer plate 14 and the screws

17 and 18 in contact. The axial abutment surfaces 34 and 36 are accordingly formed orthogonal to rotational axes 38 and 39 of the gears 31 and 32, respectively. The hubs 35 and 37 are each adapted to a diameter of a collar 40 and 41 of the screws 17 and 18, respectively. This is a direct application of solid lubricant on the Screw 17 and 18 and on the inner plate 13 and the outer plate 14 is possible, which causes a direct lubrication of the gears 31 and 32 by the gears 31 and 32 itself. Advantageously, therefore, can be dispensed with the components shown in Fig. 1, and missing in Fig. 2. Also, in turn, an exchange of conventional gears by the gears 31 and 32 to achieve a solid lubrication of a chain is made possible. In particular, the formation of the application device by means of the gears 31 and 32 causes a two-sided lubrication of the chain, not shown here. Also can be completely dispensed with a periodic lubrication or maintenance of the gears 31 and 32 by means of a viscous lubricant.

Fig. 3 shows an embodiment of a gear 42 formed as an application device. The gear 42 is preferably for use in a chain tensioner, not shown here a derailleur of a bicycle. The gear 42 is formed of a ring gear 43 having a plurality of teeth 44 and a hub 45. The ring gear 43 consists essentially of a graphite material, which serves as consume solid lubricant. The hub 45 is formed of a carbon fiber reinforced plastic, wherein the hub 45 is positively formed in the ring gear 43, so that the ring gear 43 along an inner circumferential surface 46 is connected to an outer peripheral surface 47 of the hub 45. The hub 45 has a bearing bore 48 and on both sides of a coaxial with a rotational axis molded recess 49 for receiving a disc, not shown here. The hub 45 is formed bead-like with a concave annular surface 50. A fiber structure 51 of the carbon fiber reinforced plastic is substantially visible. In particular, by using carbon fiber reinforced plastic for the hub 45, a weight reduction of the gear 42 over conventional borrowed, such gears can be achieved. Also, a lot of

Solid lubricant to a substantially intended for consumption part of the gear 42, namely the ring gear 43 limited.

Claims

claims

1. Application device for lubricating a chain drive, wherein the application device comprises a rotatable disc, wherein the disc against a chain of the chain drive to the plant can be brought, and having a rollable with the chain contact area, wherein at least the contact area is formed of a consumable solid lubricant, the can be applied to the chain.

2. Application device according to claim 1, characterized g e k e n e c i n e s t that the disc is profiled.

3. The application device according to claim 2, characterized in that a profiled disc is a toothed wheel (16, 31, 32, 42).

4. Application device according to claim 3, characterized in that the gear is a drive or an output gear.

5. Application device according to claim 3, characterized in that a gear wheel (16, 31, 32, 42) rests against a load strand or an idler strand of the chain.

6. Application device according to claim 5, characterized in that the toothed wheel (16, 31, 32, 42) is a component of a chain tensioner (12) of a derailleur (10, 33).

7. Application device according to one of claims 3 to 6, characterized in that it e e e s e e c e s e that the application device comprises two gears (31, 32, 42).

8. Application device according to one of claims 3 to 7, characterized in that it e e e e e c e e s that the contact area as a sprocket (43) is formed.

9. Application device according to claim 8, characterized in that a hub (45) is formed from a composite material or a plastic material.

10. Application device according to claim 9, characterized geke nnz eic hn et, that the composite material is carbon fiber reinforced plastic (CFRP).

11. Application device according to one of claims 3 to 7, characterized in that e e c e n e c e s that the gear (16, 31, 32) is monolithic.

12. Application device according to claim 11, characterized in that a toothed wheel (31, 32) forms a radial bearing.

13. Application device according to claim 11 or 12, characterized in that a toothed wheel (31, 32) forms a thrust bearing.

14. Application device according to one of the preceding claims, characterized in that the solid lubricant is produced on a graphite basis.

15. Application device according to claim 14, characterized in that the solid lubricant at least partially comprises graphite.

16. Application device according to one of the preceding claims, characterized in that there is a wear-reducing additive in the solid lubricant.

17. Application device according to one of the preceding claims, characterized in that the solid lubricant contains a corrosion-inhibiting additive.

18. Application device according to one of the preceding claims, characterized in that the solid lubricant has a layer structure with layers differing in their composition.

19. A method for lubricating a chain drive, wherein the chain drive comprises an application device with a rotatable disc, wherein the disc is brought against a chain of the chain drive to the plant, and wherein a contact region of the disc rolls with the chain, wherein at least the contact portion consume from a - Baren solid lubricant is formed, which is applied to the chain.

20. The method according to claim 19, characterized in that a lubrication of a bicycle chain drive takes place.