WO2016034965A1

WO2016034965A1 - Device for testing the operation of a chain

Info

Publication number: WO2016034965A1
Application number: PCT/IB2015/056252
Authority: WO
Inventors: Gianluigi Carlo Viscardi
Original assignee: Cosberg S.P.A.
Priority date: 2014-09-03
Filing date: 2015-08-17
Publication date: 2016-03-10

Abstract

Device (1) for testing the articulation of a chain segment (10) around at least one rotation axis (R). Such segment is composed of links (2, 4, 6), positioned side by side in a chain-extension direction (X) between opposite segment ends (10', 10") and joined by a plurality of pivot pins (12) identifying said axes (R). The device (1) comprises a retention member (14, 16) of at least one end of the segment (10', 10"), suitable to arrange the chain segment (10) in a rest configuration, longitudinal movement means (20) of at least one retention member (14, 16), configured to bring the member (14, 16) close to an opposite retention member (16, 14), or to a fixed abutment, so as to rotate a link (2, 4, 6) around a pivot pin (12), from the rest configuration to a partially rotated configuration, optical capturing means (22) of at least one image of the actual rotation of the link (2, 4, 6) in the partially rotated configuration and comparison means (26) between the image of the actual rotation and a template image, configured to determine whether the chain segment (10) has the reference articulation.

Description

DESCRIPTION

"DEVICE FOR TESTING THE OPERATION OF A CHAIN"

[0001] This invention relates to a device for testing the articulation of a chain segment around one or more rotation axes.

[0002] The conventional process for manufacturing a chain provides for its elongation by the progressive connection of various modular elements to one end thereof.

[0003] For this reason,, each chain element or member to be assembled is joined to a chain of a certain length, which becomes increasingly longer as its manufacture proceeds.

[0004] However, the main problem of this methodology consists of the possible errors that can be committed in the assembly of each successive modular element.

[0005] More precisely, the union of the modular elements involves sensitive operations that, if poorly executed, can compromise the correct functioning of the entire chain. In particular, a riveting operation performed too energetically or deeply has a real risk of blocking the rotation between adjacent modular elements.

[0006] This invention is therefore placed in the previous context, proposing to provide a new device for testing the articulation of a section or a segment of the chain, for example of a cutting chain, designed to check in a simple and repeatable manner the correct union of the links of which it is made.

[0007] This objective is achieved by means of a device according to claim 1, and through an assembly according to claim 12. The claims dependent on these show variants of preferred embodiments.

[0008] The object of this invention will now be described in detail, with the help of the accompanying drawings, wherein :

[0009] - Figures 1 and 2 show front views of a test device according to this invention, according to a possible embodiment, with a chain segment engaged, the latter being respectively in a rest configuration and in a partially rotated configuration;

[0010] - Figure 3 shows a view from above of the device according to Figure 1.

[0011] The reference number 1 identifies, in its entirety, a device for testing the articulation of a chain segment 10 around one or more rotation axes R.

[0012] A chain segment 10 is, for example, schematically shown in Figure 1. This figure illustrates a chain segment testable in this device. According to this variant, provided as an example of a chain, the chain is a cutting chain, being in particular a chain for a chain saw. This should not be considered as limiting the scope of this invention. [0013] In addition, the chain segment illustrated is a section isolated and mechanically disengaged from the chain, but this corresponds only to a variant.

[0014] For example, according to this variant, several segments may be joined together to create a chain of predefined length after such segments have been tested in the device described.

[0015] It follows that, in this case, only the adequately articulated chain segments will be incorporated into the growing chain, and this will result in the manufacture of a qualitatively performing chain.

[0016] According to a further variant, the chain segment is a section of a chain of a certain length, and the length of such a chain is being progressively subjected to the testing step with the device described, advancing from one section to the other disposed adjacent to each other along an assembled chain.

[0017] The chain segment 10 is composed of a plurality of links 2, 4, 6, positioned side by side in a chain- extension direction X between opposite segment ends 10', 10" and joined by a plurality of pivot pins 12 identifying said axes R.

[0018] As said, the segment ends 10', 10" need not be terminal ends, but may also be intermediate positions of the chain of predefined length. [0019] For example, the pivot pins 12 may be cylindrical or at least partly tubular.

[0020] According to a preferred variant, such as can be seen in Figure 3, the rotation axes R are substantially parallel with each other.

[0021] According to a further variant, at least one rotation axis R or the plurality thereof could be incident or perpendicular .to the chain-extension direction X.

[0022] Preferably, each of the links discussed below is in the form of a metal plate, for example with a very thin thickness with respect to its height and/or width. For example, the links testable in the device according to this invention may be performed according to document GB2109455A.

[0023] In the embodiment shown in Figure 1, the chain segment 10 comprises or consists of at least four drive links 2, four connection links 4 (only two of which are visible, the other two being hidden behind the drive links) and two cutting links 6 with allochiral cutting edges .

[0024] Other variants may, however, provide longer chain segments and/or with the related cutting edges distributed on a greater linear number of links and/or, as mentioned, segments without cutting edges. [0025] With regard to the cutting links 6, 6', in this description, the terra "allochiral" means - specifically - cutting edges with reciprocal inverse symmetry. According to the embodiment shown, the symmetrical cutting edges of the cutting links 6 are mounted along each chain segment 10 with an orientation such as to create an alternation of right and left cutting edges in the chain-extension direction .

[0026] The device 1 comprises one or more retention members 14, 16 of at least one segment end 10', 10" (preferably of both such ends), suitable to position the chain segment 10 in a rest configuration.

[0027] As shown for example in ^' Figure 1, the rest configuration is a substantially rectilinear configuration of this segment.

[0028] In other words, in the rest configuration, the pivot pins 12 are distributed along the (or parallel to the) chain-extension direction X.

[0029] Advantageously, in the rest configuration, the chain segment 10 has its maximum linear length.

[0030] According to a variant, the retention member 14, 16 could comprise a pair of jaws, at least one of which is movable with respect to the other to retain and/or release the respective segment end.

[0031] The device 1 further comprises longitudinal movement means 20 of at least one retention member 14, 16, configured to bring the member 14, 16 close to an opposite retention member 16, 14, or to bring the single member to a fixed abutment.

[0032] In this way, at least one link 2, 4, 6 is rotated around a pivot pin 12, from the rest configuration to a partially rotated configuration (for example shown schematically in Figure 2) .

[0033] In other words, an axial compression of the chain segment 10 causes the rotation of at least one link around the respective rotation axis R, so that this , segment will be deformed with respect to the rest configuration, preceding the moving together of the axial ends .

[0034] Obviously, the mode of deformation of the segment will be different in the case in which this latter possesses all the necessary mobility, or in the case wherein some joints may be blocked or damaged.

[0035] Preferably, in the partially rotated configuration, the links 2, 4, 6 are rotated around each of the present pins, with respect to the rest configuration.

[0036] According to an advantageous variant, in the partially rotated configuration, one or more pivot pins 12 are staggered in relation to the chain-extension direction X and, preferably, they are all staggered on · the same side, with respect to this direction (for example, all disposed above or below with respect to a horizontal plane - with respect to the orientation of Figures 1 and 2) .

[0037] According to an embodiment, the longitudinal movement means 20 are configured to move the retention member 14, 16 along or parallel to the chain-extension direction X.

[0038] For example, the movement direction of this member is indicated by the arrow identified by the letter M in Figure 1.

^' [0039] According to a variant, the longitudinal movement means 20 act upon each retention member 14, 16.

[0040] The device 1 comprises optical capturing means 22 of at least one image of the actual rotation of the link 2, 4, 6 in the partially rotated configuration, and storage means 24 of one or more template images, provided for a chain segment 10 having a reference articulation, i.e. for a segment suitable to achieve one or more predetermined partially rotated configurations.

[0041] In other words, the image of the actual rotation corresponds to the real configuration reached by the chain segment tested at that time. On the contrary, the template image corresponds to the ideal or desired configuration of a reference segment, when provided with the necessary mobility between the links.

[0042] Preferably, the optical capturing means 22 comprise a camera or a video camera, optionally digital.

[0043] The device 1 further comprises comparison means 26 between the image of the actual rotation and the template image, configured to determine - optionally within certain tolerances - whether the chain segment 10 is provided with the reference articulation.

[0044] So, one may be faced with different circumstances.

[0045] In a first case, the image of the partially rotated configuration will conform to one of the template images, these latter being graphical representations of the shapes that are expected for a chain segment articulated in an acceptable or correct manner.

[0046] Otherwise, for example in the case in which the rotation of the links around one or more pivot pins is somehow blocked, the actual configuration of the chain segment will be dissimilar to all the template images, so that such segment will be considered defective or nonconforming .

[0047] In this latter circumstance, this segment could therefore not be incorporated in the chain or, if the segment was already part of the chain, it may be removed from the latter to make it qualitatively acceptable.

[0048] Optionally, the device 1 could comprise transversal movement means 28, configured to work on the chain segment 10 in an incident direction Y (for example, a perpendicular direction) with respect to the chain- extension direction X.

[0049] In this way, the transversal movement means 28 can induce a reduced number of partially rotated configurations (at the limit: a single configuration) of the chain segment 10), and will therefore provide a decreased number (or a single image) of the actual rotations to the optical capturing means 22.

[0050] In other words, the mere axial compression of the chain segment may generate different configurations of partially rotated links, for which the corresponding template images could be multiple and, thus potentially difficult to manage.

[0051] However, through the use of the transversal movement means 28, it is possible to guide the chain segment along a precise trajectory, so as to make the partially rotated configuration repeatable, and so reduce the number of template images to be compared.

[0052] According to an embodiment, the longitudinal movement means 20 and/or the transversal movement means 28 comprise at least a linear actuator.

[0053] This invention also covers an assembly comprising a device 1 according to any of the embodiments illustrated previously, and at least one chain segment 10 joined to one or more retention members 14, 16 of said device.

[0054] Innovatively, the device and assembly described brilliantly overcome the drawbacks noted in relation to the prior art .

[0055] More precisely, by means of the claimed device, any possible inaccuracies or defects of assembly can be reliably detected and, in some variants, before the incorporation of the segment in the chain.

[0056] This allows preventing that one or more defective segments can become part of the structure of the chain, so that the chain generated following the .tests of this device is certain to have all the necessary mobility between the links.

[0057] Advantageously, the device covered by this invention is extremely simple, so it can be implemented in any existing production line.

[0058] Advantageously, the device covered by this invention is extremely safe from the functional point of view since the techniques described ensure reliability and long- lasting precision.

[0059] To the embodiments of the aforesaid device and assembly, one skilled in the art, in order to meet specific needs, may make variants or substitutions of elements with others functionally equivalent. [0060] Even these variants are contained within the scope of protection, as defined by the following claims.

[0061] Moreover, each of. the variants described as belonging to a possible embodiment can be performed independently of the other variants described.

Claims

1. Device (1) for testing the articulation of a chain segment (10) around one or more rotation axes (R) ;

wherein the chain segment (10) is composed of a plurality of links (2, 4, 6), positioned side by side, in a chain- extension direction (X) between opposite segment ends (10', 10") and joined by a plurality of pivot pins (12) identifying said axes (R) ;

said device (1) comprising:

- one or more retention members (14, 16) of at least one segment end (10', 10"), suitable to position the chain segment (10) in a rest configuration, for example rectilinear (Fig. 1);

longitudinal movement means (20) of at least one retention member (14, 16), configured to approach said member (14, 16) to an opposite retention member (16, 14), or to a fixed abutment, so as to rotate at least one link (2, 4, 6) around a pivot pin (12), from the rest configuration to a partially rotated configuration (Fig. 2 ) ;

- optical capturing means (22) of at least one image of the actual rotation of said link (2, 4, 6) in the partially rotated configuration;

- storage means (24) of one or more template images, provided for a chain segment (10) having a reference articulation, i.e. for a segment suitable to achieve one or more predetermined partially rotated configurations; . - comparison means (26) of the image of said actual rotation and the template image, configured to determine whether the chain segment (10) is provided with the reference articulation.

2. Device according to the previous claim, wherein the longitudinal movement means (20) are configured to move the retention member (14, 16) along or parallel to the chain-extension direction (X) .

3. Device , according to any of the previous claims, comprising transversal movement means (28), configured to work on the chain segment (10) in- an incident direction (Y) , for example a direction orthogonal to the chain- extension direction (X) , so as to induce a reduced number of partially rotated configurations of the chain segment (10), and consequently so as to provide a decreased number of images of the actual rotations to the optical capturing means (22) .

4. Device according to any of the previous cla^'ims optionally when dependent on claim 4, wherein the longitudinal movement means (20) and/or the transversal movement means (28) comprise at least a linear actuator.

5. Device according to any of the previous claims, wherein the optical capturing means (22) comprise a camera or a video camera, optionally digital.

6. Assembly comprising a device (1) according to any of the previous claims, and at least a chain segment (10) joined to one or more retention members (14, 16) of said device .

7. Assembly according to the previous claim, wherein, in the partially rotated configuration, the links (2, 4, 6) are all rotated around each of said pins in relation to the rest configuration.

8. Assembly according to claim 6 or 7, wherein, in the rest configuration, the pivot pins (12) are distributed in the chain-extension direction (X) .

9. Assembly according to any of the claims 6-8, wherein, in the partially rotated configuration, one or more pivot pins (12) are staggered in relation to the chain- extension direction (X) , and are preferably all staggered on the same side, for example above or below said direction.

10. Assembly according to any of the claims 6-9, wherein the chain segment (10) is a portion of a cutting chain, in particular of a chain for a chain saw.

11. Assembly according to any of the claims 6-10, wherein the chain segment (10) comprises or consists of at least four drive links (2), four connection links (4) and two cutting links (6) with allochiral cutting edges.

12. Assembly according to any of the claims 6-11, wherein the rotation axis (R) or the plurality thereof is incident or perpendicular to the chain-extension direction (X) .