KR20080050597A - Link plate, chain comprising said link plate, chain drive formed therewith and vehicle fitted therewith - Google Patents

Abstract

The invention relates to a link plate (4) and a plate link chain for a vehicle drive, comprising a plurality of chain links which are connected together in an articulated manner by means pressure parts (2). Said pressure parts extend in a transversal manner in relation to the longitudinal direction of the link chain. Bearing surfaces are embodied on the pressure pieces and chain links, along which the pressure pieces and the chain links are placed on top of each other in order to transmit power. The respective bearing surfaces have an optimum shape.

Description

LINK PLATE, CHAIN COMPRISING SAID LINK PLATE, CHAIN DRIVE FORMED THEREWITH AND VEHICLE FITTED THEREWITH}

The present invention relates to a chain link according to the preamble of claim 1. Other preferred construction possibilities of the invention are described in the dependent claims. The invention also relates to a link chain formed under the use of a chain link according to the invention, and to a chain driver carried out under the mounting of this type of link chain. The invention also relates to a vehicle comprising a chain drive of this type.

Chain links and link chains of the type described at the outset are known in the art in a variety of ways, as will be explained later. In addition, it is known that the force transmission capacity of this type of chain link and the link chain formed under the use of the chain link is limited, so that the chain link may first be damaged or destroyed due to the peak of the force. This breakdown can manifest as a crack in the chain link, which can be followed by a break or crack in the entire link chain, starting from the chain link, which is the force of the chain link where other chain links placed between the link members are cracked. This is because the load will be more severe by having to take over the transmission. By this heavier load, the individual chain links are closer to or even beyond the limits of their power transmission capacity.

It is an object of the present invention to provide a chain link having a higher rigidity and a link chain using the same. Wear should also be reduced and less elastic extension of the chain link or link chain occurs. In particular, it is an object of the present invention to have fewer parts assembled for the manufacture of a link chain. This is achieved according to the invention, at least by a larger link thickness of the individual chain links, ie by thickening the chain links according to the invention.

This results in a large support surface between the chain link and the pressure member or cradle member in the chain joint and a flat section component with a clean perforated surface. Thus a very good vertical contact between the cradle-shaped member or the pressure member and the chain link is achieved. By this clean support surface, the chain line shear can be reduced or prevented. With less compaction, edge flow can be reduced and, in the best case, avoided.

However, the link thickness cannot be arbitrarily increased when considering the puncture quality and the cradle-shaped member bending load or the pressure member bending load. Likewise, it is contemplated that the tool cost increases excessively with the puncture thickness.

In the configuration according to the invention of the chain link, and when using the chain link in the tooth chain, there is an additional advantage that the tilting action caused by the moment between the tooth and the link is usefully affected when the chain is inserted into the tooth wheel. This occurs because good verticalness from the link to the teeth is ensured. This improves guidance and reduces or prevents shear loads in the tooth engagement. In addition, since less compression occurs, edge flow can be reduced or prevented.

According to the invention, certain numerical ratios which can be understood numerically are presented as particularly useful. It is therefore particularly suitable when the ratio of the pitch l to the link thickness d is in the range of 3.7 to 5.5. Likewise, it is suitable when the cradle-shaped member height or the pressure member height h and the link thickness d are within a ratio of 1.3 to 1.9. Also particularly suitable is the ratio of the cradle-shaped member or the pressure member width w to the link thickness d, which is in the range between 0.8 and 1.2. It is also particularly suitable when the ratio of the web width s to the link thickness d is in the range between 0.8 and 1.2.

As mentioned above, the invention relates to a link chain, in particular for a vehicle transmission, a vehicle transmission train or a vehicle engine-assisted driver, having a plurality of chain links articulated with each other by a cradle-shaped member or a pressure member, The pressure member extends laterally with respect to the longitudinal direction of the link chain, and the support member is formed to be bent to the pressure member and the chain link, respectively, and along the support surface the pressure member and the chain link contact each other for force transmission. The supporting surface of has a width extending transverse to the longitudinal direction of the link chain, and also has an arc length in a cross section extending transverse to the width when viewed in the longitudinal direction of the link chain.

For a link chain of the type mentioned, there are various embodiments depending on the use in the vehicle driver. When used in a cone pulley continuously variable transmission (CVT), which is part of a vehicle transmission, the pressure member includes a specially formed front, whereby the tension between the cone pulley and the chain is transmitted as a frictional force. In most other uses in a vehicle driver, the link chain is a tooth chain, ie the chain link comprises a tooth on at least one side, by which the tension is transmitted between the tooth wheel and the chain. Tooth chains of this type are known in the art, for example in US Pat. No. 4,906,224. A tooth chain of this type is used at a plurality of points in the vehicle driver, for example in the case of front-middle gearboxes and in the case of front-to-lateral transmissions for eliminating axial clearances for the differentials. It is also used as a drive chain of auxiliary devices, as a valve drive-control chain of an engine or as a drive chain of other auxiliary devices of a vehicle (coolant pump, lubricant pump, air conditioner compressor, generator, starter motor, hybrid additional motor, braking power amplifier, etc.). .

A link chain of the type mentioned here consists of a plurality of chain links articulated with each other by a pressure member.

The force transmission between the pressure member and the chain link occurs at the support surface which is formed in the pressure member and the chain link and thus the pressure member and the chain link contact each other. The pressure members are represented by journals or pins which are respectively inserted in pairs as cradle-shaped joints in the two link openings, which are often combined into one large opening in the case of a chain for a cone pulley continuously variable transmission.

Different functional surfaces are formed in the pressure member. The pair of pressure members disposed opposite each other in one opening of the link chain abuts each other on the rolling area or the rolling surface. When the chain is bent, the rolling motion is executed at this point about the angle of bend preset by the geometry of the pressure member.

At the support surface of the pressure member, the pressure member abuts on the support surface of the chain link, so that surface pressure is generated between the support surface of the chain link and the support surface of the pressure member. These support surfaces must meet a plurality of requirements. On the one hand the surface pressure generated due to the formation of the support surface should not be too large and on the other hand the support surface should also be used as a torsion preventing portion so that the pressure member does not rotate into the opening of the chain link.

For this purpose, link chains are already known which comprise a divided support surface, with two radii distinctly different per segment. Thus, US Pat. No. 62,770,46 discloses a link chain having two support surfaces in pressure members having two different radii. By this different radius, since the twisting is prevented, the pressure member does not rotate into the opening of the chain link. In addition, another known link chain is described in US Pat. No. 5236399 in which two different radii are provided on the support surface or the radius midpoint is offset so that torsion prevention is performed.

In addition to this torsional protection, the support surface must also meet the requirements of link chains with tear stiffness and durability. For this purpose, the surface pressure in the contact zone between the pressure member and the chain link should not exceed a preset value. According to the conventional method, a support surface having a small curvature and a large radius of curvature was required. Thus, according to the known link chain described above, an enlargement of the radius of curvature is required to reduce the contact compression in the support surface.

The generation of compressive stress peaks in the contact area of the support member of the pressure member and the link chain is not caused by the presence of a small radius of curvature (and thus a large curvature), but is caused by the amplification of local stress peaks in the transition region between different radius of curvature. It is. It can thus be seen that in the case of known link chains a clear stress peak is provided within the transition region from one radius of curvature to the other radius of curvature even when the transition extends tangentially, ie without bending.

The corresponding figure is shown in FIG. The figure shows that a compressive stress peak occurs in the transition region between the small radius of curvature shown by K and the large radius of curvature shown by G, but the compressive stress in the small radius of curvature is substantially more absent than in the large radius of curvature. Does not indicate In contrast, it can be seen that the cause for the generation of localized high compressive stress peaks is not at the small radius of curvature, but the point of failure is the area of transition from one radius of curvature to the other.

Although the rolling surface is provided on the pressure member for twisting when the link chain is bent, the twisting of the pressure member occurs at the support surface, i.e., in the case of a link chain having a torsion preventing portion, the contact surface area of the chain link and the pressure member of the link chain. Relative motion occurs at, i.e., shear motion occurs at the support surface between the pressure member and the chain link, so that when the transition from one radius of curvature to the other radius of curvature occurs, mismatching of the support surface occurs, i.e. the curvature of the chain link It no longer coincides with the curvature of the pressure member.

This shearing causes a transition from planar support in the contact zone between the pressure member and the chain link to linear support when viewed with the width of the pressure member, thereby raising the contact pressure in the contact zone, as shown in FIG. To the maximum compression. This situation has not been considered so far, since only as large a radius of curvature as possible for reducing the load in the contact surface area between the pressure member and the chain link has been considered in accordance with conventional understanding.

On the one hand a target conflict is provided, in which the requirement of reliable surface compaction within the support surface area has to be taken into account and on the other hand the distortion of the pressure member against the chain link must be prevented.

The link chain may be formed for a vehicle driver having a plurality of chain links articulated with each other by a pressure member, the pressure member extending transverse to the longitudinal direction of the link chain, the pressure member and the chain link respectively having A curved support surface is formed, wherein along the support surface the pressure member and the chain link abut against each other for force transmission, each support surface extending transversely with respect to the longitudinal direction of the link chain and with respect to the width. When viewed in the longitudinal direction of the link chain in one transversely extending section, it has an arc length and the support surface has at least three regions with different curvatures along the arc length.

There is thus provided a link chain comprising a support surface, wherein the curve length in one section along the support surface has at least three regions with different curvatures when viewed along the longitudinal direction of the link chain, thus causing a sharp change in curvature. Is prevented, but an area having a small radius of curvature and a large radius of curvature is provided to prevent the twisting of the pressure member against the chain link.

Thus, contrary to the known perception, it is not important to have a large radius of curvature to form the smallest possible curvature in the support surface area, but rather provide a sufficient number of different curvatures of the support surface of the pressure member and the support surface of the chain link. Even if the curvature suddenly causing a high stress peak is prevented.

According to a preferred variant, the ratio of the largest curvature to the smallest curvature reaches at least factor 2. By this configuration, the torsion of the pressure member against the chain link is sufficiently prevented, and a curvature curvature exists because a sufficiently small curvature sudden change exists with the feature that the support surface is provided with at least three different curvatures along its arc length or curve length. Unacceptably high compressive stress does not occur on the supporting surface in the sudden change region.

The curvature in at least three regions can also be constant along the arc length in individual regions, i.e., at least three arc segments when the curve length or the arc length is observed in one section along the axial direction of the link chain. It is also shown to be configured. This makes the jump between the different curvatures of the arc segments small, and when viewed as the radius of curvature in the pressure member of the link chain for the vehicle driver, the jump of the individual radius of curvature can first be from 1 mm to 3 mm to 5 mm, for example, with high stress Compared to the case where the radius from 1 mm to 5 mm changes rapidly, which causes the peak.

It is also proposed that the curvatures in at least three regions are each varied along the arc length within the individual regions. In other words, this does not mean that a constant curvature is provided in the three different regions, but the curvature can be changed continuously, for example in separate regions. This allows a support surface consisting of a portion of the spiral whose curvature and radius of curvature are continuously changed along the arc length when viewed from one axial longitudinal section of the link chain. In addition to a portion of this helix, it is also possible to form a support surface consisting of a portion of an ellipse whose curvature changes continuously between minimum and maximum values when viewed from an axial longitudinal section. In addition to this configuration, it is also possible for the general support surface, which has a portion consisting of a hyperbola or parabola, or a portion of a curve whose second deflection is constant along the arc length, to be part of the curve length.

According to a variant, the support surface has a portion of the curve along the arc length, the radius of curvature of which is the smallest along the arc length, being located substantially at the center of the arc length.

Since the smallest radius of curvature is largely located at the center of the arc length, and the largest curvature is located outside each end region of the support surface, the pressure member has a structure in which the smallest radius of curvature is located at each end region of the support surface. Compared to this, the stiffness is greater, which results in less bending. If the pressure member is less bent, the tensile force is evenly distributed to all the chain links arranged side by side, so that the chain link reaches a higher durability and can transmit a higher tensile force as a whole to the link chain.

With this link chain, a pronounced contact stress sudden change no longer occurs in the transition region between different radii of curvature of the support surface. The torsional stability of the pressure member in the opening of the chain link is also higher when compared to known chain links.

The invention is explained in more detail by the figures.

FIG. 1 shows the path of surface pressure in the contact surface area of the supporting surface of the pressure member and the chain link in a known structure with two clearly different radii of curvature.

FIG. 2 is a schematic view of a known link chain for use with a CVT-transmission, with an enlarged view of the area indicated by A. FIG.

3 is an enlarged view of the chain link and the pressure member according to the first embodiment.

4 is an enlarged view of the pressure member according to the second embodiment.

Fig. 5 is an enlarged view of the pressure member according to the third embodiment and a view of a tooth chain composed of the pressure member.

6 is an enlarged view of a pressure member for explaining individual names.

FIG. 7 is a view similar to FIG. 1 for explaining the contact pressure distribution in the contact surface area between the pressure member of the link chain and the chain link. FIG.

8 is a view of a chain link with a cradle-shaped member according to the present invention.

As already mentioned above, Fig. 1 shows the path of surface pressure in the support surface region between the pressure member of the known link chain and the chain link. In the transition area between the small radius of curvature indicated by K and the large radius of curvature indicated by G, the radius of curvature rapidly changes from the small radius of curvature K to the large radius of curvature G, thereby reducing the contact pressure between the pressure member and the chain link. The peak will occur.

FIG. 2 shows a section of a known CVT-link chain 1 consisting of a plurality of cradle-shaped members 2 or pressure members 3 and a chain link 4. The area shown as A in FIG. 2 is shown enlarged in FIG. 1, and FIG. 1 shows only the pressure member 2 and the chain link 4.

3 shows an enlarged view of the pressure member 5 and the chain link 6 of the link chain 7 according to the first embodiment.

As shown, two support surface regions 8, 11 are formed between the pressure member 5 and the chain link 6, the support surface region 8 being the support surface 9 of the pressure member 5. And a supporting surface 10 of the chain link 6, which is auxiliary. Similarly, the support surface region 11 consists of the support surface of the pressure member 5 and the support surface of the chain link 6.

The pressure member 5 and the chain link 6 are in contact with each other on the support surface 9 or 10 for the purpose of force transmission. Since the chain link 6 has a predetermined width in the transverse direction with respect to the projection surface of FIG. 3 and the plurality of chain links abut the adjacent pressure members 5 with each other, the tensile force transmitted by the link chain 7 It is distributed to the individual support surface area between the pressure member and the chain link. In the axial longitudinal section extending transverse to the width of the link chain 7, each support surface 9, 10 has an arc length or a curved length, shown by the clip 12 convex upwards in the figure, respectively.

3 shows a first embodiment of a link chain according to the invention, in which the support surface 9 of the pressure member 5 and the support surface 10 of the auxiliary chain link 6 with respect thereto are formed as areas with different curvatures. Shown. In order to show this curvature in FIG. 3, regions of different curvatures with correspondingly different radii of curvature 13, 14, 15, 16 are respectively shown by broken lines, and respective curvature radii 13, 14, 15, 16 is shown as a vertical line for regions with different curvatures, in order to show the different curvatures of the support surfaces 9, 10 that are difficult to detect with the human eye.

3 clearly shows that the curvature in the region of the radius of curvature 13 is smaller than in the region of the radius of curvature 14, and the radius of curvature in the region 13 is larger than in the region 14. Correspondingly, the radius of curvature in region 15 is smaller than in region 14 and thus the curvature of region 15 is larger than in region 14. This allows the support surface 9 of the pressure member 5 and the support surface 10 of the chain link 6, which is secondary thereto, in the support surface region 8 to the arc length or curved length of the support surfaces 9, 10. Along already has three different curvatures. 3 further shows that an additional fourth region 16 is formed along the arc length at the support surfaces 9, 10 with a radius of curvature 16 different from the radius of curvature 13, 14, 15. Shown. In a corresponding manner, the support surface 11 also comprises regions with different curvatures, in which case only three regions with different curvatures are provided.

Fig. 4 shows the pressure member of the link chain according to the second embodiment, which also relates to the pressure member of the link chain for the cone pulley continuously variable transmission.

Designated by reference numeral 17 in the pressure member 5 is a rolling surface, whereby the pressure member 5 is rolled against the opposingly disposed pressure members (pressure members are paired), and the basic structure is shown in FIG. Is shown. The pressure member 5 again comprises two support surfaces 18, 19, which are arranged on correspondingly formed support surfaces of a chain link, not shown. Upper support surface 18 includes a point shown as B where the curvature maximum is located, which is the shortest line perpendicular to the support surface 18 to account for the shown radius of curvature. Since the radius of curvature increases in both directions from the point B, the curvature continuously decreases in both directions from the point B in the support surface 18. From point B, the radius of curvature increases in the direction of arrow 20 as part of the ellipse and increases in the direction of arrow 21 as part of the spiral.

4 shows similar properties from the point C having the maximum curvature at the lower support surface 19, the radius of curvature being directed toward the direction of the arrow 22 as part of the hyperbola and as part of the tip of the parabola. It increases in the direction of (23).

FIG. 5 shows a view similar to FIG. 4, wherein the pressure member 24 shown in FIG. 5 is a pressure member of a tooth chain which can be used, for example, as a tooth chain for a driver or as a tooth chain in a conveyor. The pressure member 24 also includes a rolling surface 25 on which the corresponding pressure member of the pressure member pair can be rolled. The pressure member 24 also includes an upper support surface 26 and a lower support surface 27. The configuration of the support surface 26 is that the radius of curvature from the point B (the radius of curvature is shown in dashed lines perpendicular to the contour of the support surface), along the length of the arc along the arc length shown by the clip 12 convex upward ( 26) to increase in both directions. In a corresponding manner, the radius of curvature of the support surface 27 increases in both directions from the point shown by C, with the maximum curvature (corresponding to the minimum radius of curvature).

As is also well known, the design of a pressure member with compressive stiffness is possible when the maximum curvature and the minimum radius of curvature of the support surface at approximately the center of the support surface extend along the arc length or curve length of the support surface.

Figure 6 illustrates this relationship. By reference B or C, the points of the upper support ground or the lower support surface are again shown, which includes the maximum and minimum radius of curvature in each support surface. As shown in the figure, the point B or C is located approximately at the center of the arc length 28, and below it extends an area having a radius of curvature of the dashed line. As mentioned above, the point with the maximum curvature is located approximately at the center of the support surface along the arc length (measured along the arc length 28), with the point B or C being between 40 and 60% of the arc length 28. It can be seen that similar desirable effects are reached when located in the phosphorus region (D). This area indicates the range where the tangent forms an angle of 30 to 60 degrees with respect to the lower supporting surface of the pressure member, which angle is measured between the tangent 29 and the chain travel direction 30. If the point with the maximum curvature of each support surface is located within 40 to 60% of the total length of the arc length 28 or within the range of 30 to 60 degrees of the tangent 29 with respect to the chain travel direction 3 A rigid pressure member is provided with low quality risk, which can result in a higher tension that can be transmitted by the link chain or the tooth chain.

Fig. 7 shows the contact pressure distribution of the lower support surface selected in the figure between the pressure member 5 of the link chain (the concept of the link chain also includes the tooth chain) and the chain link 6. Comparing the contact pressure distribution of the known link chain according to FIG. 1 with the contact pressure distribution of the link chain according to FIG. 7, it is evident that the contact pressure peak shown in FIG. 1 disappears. In order to show the contact pressure distribution of the support surface, since the drawings normalized to each other were selected in the two figures, the length of each arrow also indicates the magnitude of the contact pressure at each observed point of the support surface. It can be seen visually that the clear contact pressure peaks as shown in FIG. 1 disappear.

8 shows a cradle-like member or pressure member 2 of a chain link 4 and a pressure member pair according to the invention. Reference numerals used in the drawings are used to describe the numerical ratios already mentioned and have the meanings given below.

d: link thickness

s: web width

l: pitch

h: Cradle type height (cradle type pressure member height or pressure member height)

w: cradle type member width

b: inner web width

The numerical ratios according to the invention, already presented, are as follows:

l / d = 3.7 to 5.5 and / or

h / d = 1.3 to 1.9 and / or

w / d = 0.8 to 1.2 and / or

s / d = 0.8 to 1.2

The advantages given from this have already been described above.

<Drawing code list>

1: link chain

2: pressure member

3: pressure member

4: chain link

5: pressure member

6: chain link

7: link chain

8: support surface area

9: support surface of the pressure member

10: support surface of chain link

11: support surface area

12: convex clip up

13: radius of curvature

14: radius of curvature

15: radius of curvature

16: radius of curvature

17: rolling surface

18: support surface

19: support surface

20, 21, 22, 23: arrows

24: pressure member

25: rolling surface

26: upper support surface

27: lower support surface

28: arc length

29: tangent

30: chain progress direction

B: point with maximum curvature

C: point with maximum curvature

D: 40 to 60% of the arc length

d: link thickness

s: web width

l: pitch

h: cradle type height

w: cradle type member width

b: inner web width

Claims (11)

A chain link, especially for a link chain for a vehicle driver, provided for a functional connection with at least one joint member, such as a cradle member, a pressure member or a cradle type pressure member, the numerical ratio of the cradle member height to the link thickness. The chain link for the link chain between this 1.3 and 1.9. 2. The chain link of claim 1 wherein the ratio of the pitch of the link chain to the link thickness is between 3.7 and 5.5. The chain link according to claim 1 or 2, wherein a numerical ratio of the width of the cradle-shaped member to the link thickness is between 0.8 and 1.2. 4. The chain link according to any one of claims 1 to 3, wherein a numerical ratio of the width of the web to the link thickness is between 0.8 and 1.2. Chain link for a link chain according to any one of the preceding claims, characterized in that it is manufactured as a perforated part, in particular a precision perforated part. 6. The chain link of claim 5 wherein the flat section portion reaches at least approximately 70% of the link thickness. A link chain for a link chain, characterized by the use of the chain link according to any one of claims 1 to 6. 8. A link chain according to claim 7, consisting of a CVT-chain. 8. A link chain according to claim 7, which is composed of a tooth chain. Use of a link chain according to any one of claims 1 to 9, characterized in that the chain drive. A vehicle characterized by the use of a chain drive according to claim 10.

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