FI20207089A1 - Nose wheel of a chain saw and lubrication thereof - Google Patents

Abstract

The invention relates to nose wheels (21) on a chain saw (3) on, for example, a harvester head (2), which nose wheel can be attached to the chain saw bar (11) and rotatably attached relative to the plane of the sword to support the movement of the saw chain (12). At least one surface (31) of the nose wheel is formed with at least one lubrication groove (33, 34) leading from the outer edge (27) of the nose wheel or from the vicinity of the outer edge to the center portion (32) of the tip wheel to guide lubricant between the outer edge and the center portion. The invention further relates to a chain saw bar (11), a harvester (1) and a method for lubricating the saw chain (12) and the tip wheel (21) of a chain saw (3) on a harvester head (2).

Description

Chainsaw tip wheel and its lubrication

TECHNICAL FIELD OF THE INVENTION The invention relates to a chain saw tip wheel, a chain saw flange, a harvester head as set out in the preambles of the independent claims set out below, and to a method for lubricating a harvester head chain saw blade chain and a tip wheel.

BACKGROUND OF THE INVENTION A chain saw, like a harvester head chain saw, has a flange around which the saw chain moves and on which the chain rests. The flange generally comprises an elongate plate-like body in which a chain groove is formed around the edge of the flange to control the passage of the saw chain. The base of the flange typically has an attachment portion for attaching the flange to the harvester head body. The body of the harvester head has power tools for operating a chain saw, e.g. to move the saw chain. The tip of the flange typically has a gear wheel, i.e. a tip wheel, which supports the movement of the saw chain. The tip wheel is rotatably attached to the flange via a bearing in the direction of its plane. The purpose of the tip wheel is to carry the load caused by the tightening of the saw chain over the tip of the flange.

One of the most common problems with a harvester head chain saw is a break in the tip wheel. Usually the tip wheel is damaged due to lack of lubrication. In this case, the tip wheel overheats, cuts and / or breaks due to the forces exerted on it by the chain. The problem is becoming more and more urgent, as the N chain speeds and the force used in chainsaws are constantly being increased.

3 25> Lubrication of the tip wheel is traditionally done by forming an lubrication channel E in the flange, along which a lubricant is introduced into the saw chain. As the saw chain moves around the 2 flanges, the lubricant lubricates the saw chain, which also transports the lubricant to the = tip wheel. Efforts have been made to improve the lubrication of the tip wheel by increasing the amount of lubricant fed to the blade chain O 30, but this will increase the amount of lubricant injected into the environment.

US5669140 A discloses a chain saw flange in which lubricant is transferred along a lubricant tube arranged in the flange close to the tip wheel. The prior art does not provide a satisfactory solution for tip wheel lubrication. There is not enough or a lot of lubricant wasted, the lubricant does not stay clean, its efficient discharge to and from the top wheel bearing has not been resolved.

OBJECT OF THE INVENTION The object of the present invention is to reduce or even eliminate the above-mentioned problems occurring in the prior art. It is an object of the present invention to provide a solution by which the lubrication of the tip wheel of a chain saw is more efficient and the service life of the tip wheel is increased. - It is an object of the present invention that the lubricant coming onto the tip wheel of the chain saw and its bearings is as pure as possible. It is an object of the present invention to provide a more reliable harvester head, chain saw and chain saw flange.

Some of the objects of the present invention are also to reduce the consumption of lubricant, to protect nature from the lubricant, to reduce the contamination of the harvester and the harvester head, to increase the efficiency of wood felling. & 3 25 BRIEF DESCRIPTION OF THE INVENTION> Mm.

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The application examples and advantages mentioned in this text apply mutatis mutandis to the tip wheel according to the invention, the chain saw flange, the harvester head, as well as other objects of the invention, although it is not always mentioned separately.

Pulleys, Chainsaws and their flanges, harvester heads and the lubrication used in them are known per se and their bases will not be discussed in more detail in this text.

A typical chain saw tip wheel according to the invention is rotatably attached to the chain saw flange with respect to it and its plane. The purpose of the tip wheel is to support the movement of the chain saw blade chain. At least one lubrication groove leading from the outer edge of the tip wheel or in the vicinity of the outer edge thereof to guide the lubricant between the outer edge and the central part is formed on at least one surface of the tip wheel.

At the base of a typical chain saw flange, there are fastening means for attaching the flange to the chain saw body. The tip of the flange has a tip wheel according to the invention supporting the movement of the chain saw blade chain. The tip wheel is attached to the flange via a bearing.

A typical harvester head according to the invention comprises a chain saw comprising a flange according to the invention.

S N In one embodiment, the tip wheel comprises 3 toothed edges to support the saw chain; 2 - a bearing in its central part to allow the movement of the tip wheel with respect to the flange of the chain saw E; 8 - two tip wheel surfaces between toothing and bearing. The surfaces of the tip wheel S are generally planar and substantially parallel to each other.

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In one application, at least one lubrication groove formed in the surface of the tip wheel is arranged to guide the lubricant between the toothing and the center portion of the tip wheel, for example the bearing. A typical method according to the invention for lubricating a chainsaw blade chain and a sprocket of a harvester head comprises at least the following steps: - transferring the proximity of the outer edge towards its center along a lubricating groove; - transfer lubricant from the tip wheel to the saw chain.

The way of describing the invention is to say that at least one lubrication groove is formed in the surface of the tip wheel, which helps to transport the lubricant from the edge of the tip wheel towards its center. The lubrication groove can extend, for example, from the outer edge of the tip wheel to its inner parts, for example the bearings. The first end of the lubrication groove may be, for example, in the toothing of the outer edge of the tip wheel, at the tooth, at the edge of the tooth, or on the tooth surface at a distance from the edge of the tip wheel. The other end of the lubrication groove can be, for example, in the middle of the tip wheel or at the bearing system. The other end of the lubrication groove may be in the center of the tip wheel at the edge of the tip wheel or in the opening for lubricant.

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N S 25 It has now been found that the lubrication of the tip wheel can be improved by forming at least one lubrication groove on its surface. Along the lubrication groove, the lubricant can be conducted = more efficiently between the outer edge and the center of the tip wheel. If in the prior art solution S lubricant is obtained in connection with the toothing S of the outer edge of the tip wheel, the slight rotational movement of the tip wheel has prevented the efficient S 30 from passing into the center part of the tip wheel, for example the bearing system.

One advantage of the invention is that the lubrication is applied directly to the right place, i.e. to the tip wheel.

This can reduce the consumption of lubricating oil.

It is also an advantage that the lubricant can now be guided along the lubrication groove in an even cleaner location at various points on the tip wheel, the tip wheel centers and the tip wheel bearings.

It is also an advantage that the lubricant obtained on the tip wheel 5, for example in the middle thereof, is spread evenly on the saw chain, so that the lubrication of the saw chain becomes more efficient.

The lubricant on the saw chain is also kept cleaner.

A lubricant that travels to the entire sprocket or a large portion of the sprocket effectively cools the sprocket and chain, which is an advantage especially during the hot season.

By means of the invention, the amount of lubricating oil can be reduced and less released into the environment.

By means of the invention, the drainage, splashing of lubricating oil and the mist of lubricant generated from the saw are reduced, whereby the harvester head and the forest machine remain cleaner.

Thanks to better lubrication, less force is applied to the saw chain, so its elongation is reduced and service intervals are extended.

The service life of the tip wheel increases, so does the service life of the chain saw flange.

Harvester head and felling will be more efficient.

The invention is applicable to at least almost all flange models and harvester heads.

The tip wheel can be only a few millimeters thick, for example 2-5 mm.

In one embodiment of the invention, the lubrication grooves are made by machining the surface of the tip wheel, for example by milling.

The shape and dimensioning of the lubrication groove can be selected to suit each situation.

The depth of the lubrication groove can be, for example, 0.1-0.5 mm, 0.2-0.4 mm or 0.2-0.3 mm.

The width of the lubrication groove can be, for example, 0.3-2 mm, 0.5-0.5 mm or 0.5-1 mm. & 3 25 In one embodiment of the invention, the at least one lubrication groove has a straight shape. > In one application, the lubrication groove is parallel to the radius of the tip wheel.

Straight lubrication- E groove is easy to make. 8 = In one embodiment of the invention, the lubrication groove has a shape deviating from the direction of the radius O 30 of the tip wheel, in one embodiment curved.

The oblique or curved shape can affect the centrifugal force on the lubricant caused by the rotational movement of the tip wheel.

In one embodiment of the invention, the at least one lubrication groove is oblique or turned towards the rotation of the tip wheel when viewed from the central part towards the outer edge. In other words, the end on the outer edge of the lubrication groove is above the end in the direction of rotation of the tip wheel. Due to this, the effect of the centrifugal force on the lubricant due to the rotational movement of the tip wheel is reduced, and thus the transfer of the lubricant from the outer edge to the center is facilitated. In one embodiment of the invention, the at least one lubrication groove is oblique or turned against the direction of rotation of the tip wheel when viewed from the center towards the outer edge. In other words = the end on the outer edge of the lubrication groove is in the direction of rotation of the tip wheel = behind the end on its center. This increases the effect of centrifugal force on the lubricant. This makes it easier to move the lubricant from the center of the tip wheel towards the outer edge.

In one embodiment of the invention, the tip wheel is provided with both - at least one lubrication groove which is inclined from the center towards the outer edge or turned towards the direction of rotation of the tip wheel and - at least one lubrication groove which is inclined from the center towards the outer edge or turned against the direction of rotation of the tip wheel. In this way, the lubrication grooves enhance the movement of the lubricant both towards the center of the tip wheel and away from the center.

S N In one embodiment of the invention, there is an even number of lubrication grooves, where every other = 25 lubrication groove is oblique toward the direction of rotation of the tip wheel from the center toward the outer edge, and every other is oblique to the direction of rotation of the tip wheel. E This provides even lubrication. 3 3 In one embodiment of the invention, there are lubrication grooves on both surfaces of the tip wheel. O 30 This makes lubrication more efficient on both sides of the tip wheel. In this way, the tip wheel can also be reversed during maintenance without deterioration during lubrication.

In one embodiment of the invention, a lubricant tube leads from the base of the flange to the tip to direct the lubricant from the base of the chain saw directly to or near the tip wheel. In this way, the lubricant is obtained clean on the tip wheel.

In one application, the lubricant tube is placed in a groove machined, for example milled, in the flange. In one application, at least most of the length of the lubricant tube is located in the groove machined in the flange. The lubricant tube may be, for example, metal or an alloy such as copper, brass, iron or steel. A relatively soft metal such as copper or brass is easy to handle, such as bending. A groove tube placed in the groove can be attached to the groove, for example, by filling the groove with a solder such as tin. For example, the filled groove can be sanded and painted. The groove and the lubricant pipe therein can also be covered with a protective plate or a protective strip, for example.

In one embodiment of the invention, at least a portion of the lubricant tube extends to the outer edge of the tip wheel = to conduct lubricant in the lubricant tube to the tip wheel. In this way, the lubricant can be led from the lubricant tube directly to, for example, the surface of the tip wheel, the toothing, the center of the tip wheel or the bearing.

In one embodiment of the invention, at least the tip part of the flange comprises two overlapping body plates, between which a tip wheel is arranged, the lubricant tube being arranged o in a groove formed in said body plate at least in the tip part of the flange. The bearing of the tip wheel N may be supported on said frame plates. In one embodiment, the tip wheel 3 25 is housed mainly in a housing formed between the frame plates. In one application, the lubricant tube extends inside said housing. Typically, at least the toothing of the outer edge of the tip wheel E extends at least partially outside the housing, where the toothing 2 supports the saw chain around the flange. S 30 In one embodiment of the invention, the lubricant tube is at least partially opened or split in its longitudinal direction at the tip wheel. In this case, the opened part of the tube can be placed towards the surface of the tip wheel. The opened lubricant tube and the surface of the tip wheel define a passage for the lubricant through which the lubricant can be led to the outer edge of the tip wheel and further towards the center of the tip wheel. If the tip wheel has a lubrication groove, some of the lubricant will grip the lubrication groove and travel toward the center of the tip wheel.

In one embodiment of the invention, the intact, i.e. unopened, portion of the lubricant tube faces the outer surface of the flange and its tip body body. In one application, the surface of the intact portion of the lubricant tube is flush with the outer surface of the body plate. In one embodiment, the surface of the intact portion of the lubricant tube forms part of the outer surface of the flange, at least at the tip portion of the flange. In one embodiment of the invention, the lubricant tube branches off before the tip wheel, with some of the lubricant being applied to the edge of the flange other than at the tip wheel for direct lubrication of the saw chain.

One possibility for carrying out the invention, such as the tip wheel, the flange, the harvester grapple and the lubrication method, is to use said lubricant tube, at least part of which extends inside the outer edge of the tip wheel without the aforementioned lubrication grooves. In this case, too, the lubricant is derived from the lubricant tube directly to the tip wheel, its teeth and / or its surfaces. Also in this embodiment, the tip portion of the flange may comprise a tip wheel housing or two overlapping frame plates between which the tip wheel is arranged. The lubricant tube could be split or opened as described above. Many of the applications, N options, and benefits mentioned in this text also apply to applications without lubricants formed on the 3 25 tip wheel. 0

E BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying schematic drawing, in which O 30 Figures - show a harvester; Figure 2 shows a flange of a chain saw according to the invention; Fig. 3 - shows the tip part of the flange of Fig. 2 partially opened;

Fig. 4 shows a section A-A of the flange of Fig. 2; and Figure 5 shows a section B-B of the flange of Figure 2.

DETAILED DESCRIPTION OF EXAMPLES OF THE FIGURES For the sake of clarity, the same reference numerals are used in different figures and embodiments for some corresponding parts. Figure 1 shows a harvester 1, i.e. a forestry tractor, which performs the steps of felling wood from felling to stacking. Harvester head 2 is the part of the harvester with which the tree is cut and pruned. The harvester head usually has feed rollers, pruning blades, measuring devices such as sensors, a chain saw 3 and a so-called tilt 4. The tilt allows the harvester head to operate horizontally and vertically. In general, the harvester head is attached to the harvester crane 5 by means of a rotating joint, i.e. a rotator 6, by means of which the harvester head 2 can be rotated about its vertical axis.

When felling the wood, the harvester head 2 is placed at the base of the tree, the tree is gripped by the harvester head actuators and the tree is cut with a chain saw 3. The devices are used to monitor the movement and position of the tree trunk. By means of a chain saw 3 rotatable relative to the harvester head and the tree trunk held therein, logs of suitable length are cut from the wood. o Figure 2 shows the flange 11 of a chain saw 3, around which the saw chain 12 of the saw moves N and on which the chain rests. The flange 11 generally comprises an elongate plate-like body 13 25 in which a chain groove 14 (see Fig. 4) is formed around the edge of the flange to guide the passage of the blade chain 12. A lubricant groove 15 is also formed in the flange and a lubricant tube 16 is inserted therein to bring the lubricant from the flange root 17 to the tip portion 18 thereof. The tip portion 18 of the flange has an O 30 gear or tip wheel 21 supporting the movement of the saw chain 12, which is shown in Fig. 3. The function of the tip wheel 21 is to carry the load caused by the tightening of the saw chain 12 over the tip portion 18 of the flange.

Several different structures are known for the chain saw flange. In the example of the figures, the flange 11 is formed at the section of Fig. 4 by a single metal plate 13. The section of Fig. 4 shows schematically how a lubricant groove 15 is machined on the surface of the flange 11 and a lubricant pipe 16 is placed in it. the point on the pipe would be smoothed. The bottom of the lubricant groove 15 is formed to conform to the shape of the tube 16. The size of the lubricant pipe 16 can be selected according to the current need. Often quite a small pipe diameter is sufficient. However, the larger pipe does not clog so easily, for example due to debris. Figure 3 shows in more detail the tip part 18 of the flange, partially opened. Figure 5 shows a section B-B of the flange tip portion 18. The tip wheel 21 is rotatably attached to the flange 11 by means of rivets 22 in the direction of the plane of the flange. The tip portion 18 of the flange comprises two overlapping frame plates 24 and 25, between which - the tip wheel 21 is arranged. The tip wheel bearing 23 is supported on the frame plates 24 and

25. The tip wheel 21 is predominantly housed in a housing 26 formed between the body plates. The tips of the teeth 28 extend partially outside the housing 26 to support the saw chain 12.

The lubricant tube 16 is split at the tip wheel, forward from the point 29 toward the tip wheel in the plane of the flange 11 and the plane of the tip wheel 21. The open portion of the tube 16 is positioned toward the surface 31 of the teeth 28 of the tip wheel 21. The open lubricant tube 16 and the tooth surface 31 of the N tip wheels define a passageway 37 for the lubricant. the length can be adapted to suit each situation. It is possible to extend the passage 37 up to the bearing system 23. 8 = Four lubricant supply grooves have been machined on the surface 31 of the tip wheel 21, i.e. the lubrication grooves O 30 33 and 34. The grooves begin at the surface of the teeth 28 of the tip wheel and continue a distance toward the center portion 32 of the tip wheel. All four grooves are on the same side of the tip wheel 21. Fig. 3 shows three grooves, one groove 33 is hidden under the body plate 24, but it is also shown in Fig. 5. The lubrication grooves 33 are slightly curved in the direction of rotation of the tip wheel (clockwise in Fig. 3) and bearings 23. The lubrication grooves 34, when viewed from the center of the tip wheel, are slightly curved against the direction of rotation of the tip wheel to allow the lubricant to travel better away from the bearings 23 and forward toward the saw chain 12. Thus, every other groove is curved in a different direction. Some of the lubricant coming from the lubricant tube 16 is due to the lubrication grooves 33 and 34 and - travels there towards the center portion 32 of the tip wheel and towards the bearings 23. Not all lubricant enters the grooves 33 and 34 from the surface of the tip wheel 12 the grooves 33 and 34 are formed only on one surface 31 of the tip wheel. formed - lubrication grooves. The invention is not intended to be limited to the examples given, but the scope of the invention is determined by the independent claims. The dependent claims present a few preferred embodiments of the invention.

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Claims (16)

PATENT CLAIMS A sprocket (21) of a chain saw (3) rotatably attached to the chain saw flange (11) relative thereto and in a plane thereof to support the movement of the chain saw blade chain (12), characterized in that at least one tip wheel surface is formed on the at least one sprocket surface (31). a lubrication groove (33, 34) leading from the outer edge (27) or in the vicinity of the outer edge towards the center portion (32) of the tip wheel to guide the lubricant between the outer edge and the center portion. A tip wheel according to claim 1, characterized in that the tip wheel (21) comprises - at its outer edge a toothing (28) for supporting the saw chain; - in its central part, the bearing (23) to allow = the movement of the tip wheel - with respect to the flange (11) of the chain saw; - two planar surfaces of the main parallel tip wheel (31, 35) between the toothing and the bearing; wherein the lubrication grooves (33, 34) are arranged to guide the lubricant between the toothing and the center portion. Tip wheel according to Claim 1 or 2, characterized in that the at least one lubrication groove (33) is inclined or curved from the central part (32) towards the outer edge (27) in the direction of rotation of the tip wheel. S N A wheel according to one of the preceding claims, characterized in that the S 25 at least one lubrication groove (34) is inclined or curved from the central part (32) towards the outer edge (27) in the direction of rotation of the tip wheel. Tip wheel according to one of the preceding claims, characterized in that = there is an even number of lubrication grooves (33, 34), each second lubrication groove (33) being oblique or curved towards the outer edge in the direction of rotation of the tip wheel, and every other (34) is oblique or curved against the direction of rotation of the tip wheel. Tip wheel according to one of the preceding claims, characterized in that the at least one lubrication groove is curved. Tip wheel according to one of the preceding claims, characterized in that the at least one lubrication groove is straight. A chain saw flange (11) having mounting means (19) at the base (17) for attaching the flange to the body of the chain saw (3) and having a tip wheel (21) supporting the movement of the chain saw blade chain (12) attached to the flange of the bearing (23). rotatably in the direction of the plane of the flange, characterized in that the tip wheel (21) complies with one of the preceding claims 1 to 7. Flange according to Claim 8, characterized in that a lubricant pipe (16) leads from the base of the flange (11) to the tip to guide the lubricant from the base of the chain saw to the tip wheel. Flange according to Claim 9, characterized in that at least part of the lubricant tube (16) extends upwards inside the outer edge (27) of the tip wheel to guide the lubricant in the lubricant tube up to the tip wheel (21). SN Flange according to one of the preceding claims 9 to 10, characterized in that at least the tip part (18) of the flange comprises two overlapping body plates (24, 25) between which the tip wheel (21) is arranged, the lubricant pipe (16) being arranged at least in the groove (36) formed in said body plate (24) in the tip portion (18) of the flange. Flange according to one of the preceding claims 9 to 11, characterized in that the O 30 lubricant pipe (16) is at least partially opened or split in its longitudinal direction at the tip wheel (21). Harvester head (2) comprising a chain saw (3), characterized in that the chain saw flange (11) is according to one of the preceding claims 8 to 12. A method for lubricating a saw chain (12) and a sprocket (21) of a chainsaw (3) of a harvester head (2), the method comprising at least the step of: a tip wheel (21) arranged on the tip (18), characterized in that the method further comprises at least the step of: - transferring lubricant from or near the outer edge (27) of the tip wheel or from the vicinity of the outer edge towards its central lubrication groove (33, 34) - the lubricant is transferred from the tip wheel (21) to the saw chain (12). Method according to Claim 14, characterized in that - the lubricant is transferred along the lubricant tube (16) - up to the inside of the outer edge (27) of the tip wheel (21), i.e. up to the tip wheel (21). Method according to Claim 14 or 15, characterized in that the chain saw flange (11) is according to one of the preceding claims 8 to 12. O OF O OF LÖ <Q 0 I a a O 00 O OF O OF O OF