BAND-SAW BLADE CHANGING DEVICE AND METHOD

Abstract

A device for mounting and dismounting a band-saw blade has a movable support frame and a plurality of retaining elements distributed on said support frame and configured to temporarily adhere to the outer flat side of the band-saw blade at various locations along the contour of the band-saw blade, thereby exerting an outwardly directed force on the outer flat side of the band-saw blade.

Claims

1. A device for at least one of mounting and dismounting a band-saw blade onto or from a band-saw, the band-saw blade having, when mounted on the band-saw, a closed contour and comprises two opposing narrow sides, at least one of which is provided with a plurality of saw teeth or a cutting material, and comprises two opposing flat sides interconnecting the narrow sides, one of the two opposing flat sides is an outwardly facing outer flat side and the other one is an inwardly facing inner flat side, the device comprising: a support frame; a support structure configured to support and move the support frame along at least two axes aligned transversely to each other; and a plurality of retaining elements distributed on the support frame and configured to selectively attach to the outer flat side of the band-saw blade at various locations along the closed contour of the band-saw blade, thereby exerting an outwardly directed retaining force on the outer flat side of the band-saw blade; wherein the support frame is suspended from the support structure; wherein the support structure comprises a cantilever beam extendable along one of the axes; and wherein the support structure is configured to rotate the support frame about one of the axes.

2. The device of claim 1, wherein the support structure is moveable relative to the band-saw.

3. The device of claim 1, wherein the support structure comprises a guide rail and a carriage longitudinally displaceable along the guide rail.

4. The device of claim 1, wherein the retaining elements each are configured to adhere exclusively to the outer flat side of the band-saw blade.

5. The device of claim 1, wherein the retaining elements each comprise at least one of a vacuum lifter, a suction cup, a permanent magnet, an electromagnet, or a temporarily sticking retaining element.

6. The device of claim 1, wherein the support frame comprises two opposing straight sections and at least one arcuate section interconnecting the two straight sections, wherein at least one retaining element of the plurality of retaining elements is disposed in each of the two straight sections and the arcuate section.

7. The device of claim 1, wherein the support frame comprises two opposing straight sections and two opposing arcuate sections each connecting the two straight sections, wherein at least one retaining element of the plurality of retaining elements is disposed in each of the two straight sections and one of the two arcuate portions, and wherein no retaining element is disposed in the other of the two arcuate portions.

8. A device for mounting or dismounting a band-saw blade which, when mounted on a band-saw, has a closed contour and comprises two opposing narrow sides, at least one of which is provided with a plurality of saw teeth or a cutting material, and comprises two opposing flat sides interconnecting the narrow sides, one of the two opposing flat sides being an outwardly facing outer flat side and the other one being an inwardly facing inner flat side, the device comprising: a movable support frame; and a plurality of retaining elements distributed on the support frame and configured to temporarily adhere to the outer flat side of the band-saw blade at various locations along the closed contour of the band-saw blade, thereby exerting an outwardly directed retaining force on the outer flat side of the band-saw blade.

9. The device of claim 8, wherein the retaining elements each are configured to adhere exclusively to the outer flat side of the band-saw blade.

10. The device of claim 8, wherein the retaining elements each comprise at least one of a vacuum lifter, a suction cup, a permanent magnet, an electromagnet, and/or a temporarily sticking retaining element.

11. The device of claim 8, wherein the support frame comprises two opposing straight sections and at least one arcuate section interconnecting the two straight sections, wherein at least one retaining element of the plurality of retaining elements is disposed in each of the two straight sections and the arcuate section.

12. The device of claim 8, wherein the support frame comprises two opposing straight sections and two opposing arcuate sections each connecting the two straight sections, wherein at least one retaining element of the plurality of retaining elements is disposed in each of the two straight sections and one of the two arcuate portions, and wherein no retaining element is disposed in the other of the two arcuate portions.

13. The device of claim 8, further comprising a support structure configured to support and move the support frame along at least two axes aligned transversely to each other.

14. The device of claim 13, wherein the support structure is configured to move the support frame along three orthogonally aligned axes.

15. The device of claim 13, wherein the support structure comprises a cantilever beam extendable along one of the axes.

16. The device of claim 13, wherein the support structure is configured to rotate the support frame about one of the axes.

17. The device of claim 13, wherein the support frame is suspended from the support structure.

18. A method of at least one of mounting and dismounting a band-saw blade onto a band-saw or from a band-saw, the band-saw blade having a closed contour when mounted on the band-saw and comprising two opposing narrow sides, at least one of which is provided with a plurality of saw teeth or a cutting material, and two opposing flat sides interconnecting the narrow sides, one of the opposing flat sides being an outwardly facing outer flat side and the other one being an inwardly facing inner flat side, the method comprising the steps of: providing a movable support frame having a plurality of retaining elements distributed on the support frame; moving the support frame toward the band-saw blade to be mounted or dismounted, which band-saw blade is located at a first location; activating the plurality of retaining elements to temporarily attach the retaining elements to the outer flat side of the band-saw blade at various locations along the closed contour of the band-saw blade, thereby exerting an outwardly directed retaining force on the outer flat side of the band-saw blade; moving the support frame, together with the band-saw blade temporarily attached thereto, from the first location to a second location; deactivating the plurality of retaining elements to release the band-saw blade from the support frame and leave the band-saw blade in the second location; wherein, when the band-saw blade is mounted, the first location is a storage location for the band-saw blade and the second location is a band-saw, and wherein, when the band-saw blade is dismounted, the first location is the band-saw and the second location is the storage location for the band-saw blade.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0054] An exemplary embodiment of the invention is shown in the drawings and explained in more detail in the following description. It shows:

[0055] FIG. 1 a top view onto a band-saw blade changing device according to an exemplary embodiment of the present invention;

[0056] FIG. 2 a side view of the band-saw blade changing device of FIG. 1 in a first state;

[0057] FIG. 3 a side view of the band-saw blade changing device of FIG. 1 in a second state;

[0058] FIG. 4 a perspective view of the band-saw and band-saw blade changing device of FIG. 1;

[0059] FIG. 5 a detail from FIG. 4;

[0060] FIG. 6 a top view onto the band-saw and band-saw blade changing device of FIG. 1 in a first state;

[0061] FIG. 7 a top view onto the band-saw and band-saw blade changing device of FIG. 1 in a second state; and

[0062] FIG. 8 a top view onto the band-saw and band-saw blade changing device of FIG. 1 in a third state.

EMBODIMENTS

[0063] FIG. 1 shows an installation comprising a band-saw and a band-saw blade changing device according to an exemplary embodiment of the present invention. The installation is designated in its entirety by the reference numeral 100 in FIG. 1. The band-saw blade changing device is designated by reference numeral 10. The band-saw is designated by reference numeral 12.

[0064] For a better understanding, the individual components as well as the structure of the band-saw 12 will first be discussed in the following, before the components and the structure of the device 10 are explained in detail.

[0065] The band-saw 12 has a band-saw blade 14 which is configured to form a closed, oval loop. This band-saw blade 14 is mounted on two band-saw rollers 16, 16′, at least one of which is rotationally driven during operation of the band-saw 12. The band-saw blade 14 thus moves around the two band-saw rollers 16, 16′ during operation of the band-saw 12, so that an endless cut can be produced with the aid of the band-saw 12. The band-saw blade 14 is therefore often also referred to as an endless saw blade.

[0066] Towards the rear as well as in the upper area of the band-saw 12, the band-saw blade 14 as well as the rollers 16, 16′ are typically safeguarded by a cover 18. This cover 18 is also referred to as a roller guard. For guiding the saw blade 14, the band-saw 12 further comprises a plurality of guide elements 20. These prevent the saw blade 14 from leaving its predetermined path.

[0067] The contour of the band-saw blade 14 or its path, as mentioned above, is substantially oval with two opposing straight sections 22, 22′ extending in the area between the two band-saw rollers 16, 16′ and two opposing arcuate sections 24, 24′ interconnecting the two straight sections 22, 22′ of the band-saw blade 14 and corresponding to the areas of the band-saw blade 14 where it rests on the band-saw rollers 16, 16′.

[0068] In the exemplary embodiment shown in FIG. 1, the band-saw 12 is inclined with respect to the vertical line 26. This inclination is indicated in FIG. 1 by the angle α. The angle α indicates the angle that the longitudinal axis 28 of the band-saw 12 makes with the vertical 26. This longitudinal axis 28 of the band-saw 12 corresponds to an imaginary connecting line of the axes of the two band-saw rollers 16, 16′.

[0069] The shape and construction of the band-saw blade 14 are best seen in FIG. 4. The band-saw blade 14 has two opposing narrow sides 30, 32, at least one of which is provided with a plurality of saw teeth 34. In the present exemplary embodiment, both narrow sides 30, 32 have saw teeth 34. In the present case, therefore, it is a double-sided cutting band-saw blade 14. However, this need by no means necessarily be the case.

[0070] Between the two narrow sides extend the flat sides 36, 38 of the band-saw blade 14. These two flat sides 36, 38 are preferably designed parallel to each other and also form two opposite sides of the band-saw blade 14. As the name implies, these two flat sides 36, 38 are preferably designed as plane or flat sides of the band-saw blade 14. The outer flat side 36 runs along the outer periphery of the band-saw blade 14, thus forming its outer side. The inner flat side 38 runs along the inner circumference of the band-saw blade 14, forming its inner side. In other words, the outer flat side 36 of the band-saw blade 14 is the side of the band-saw blade 14 facing away from the band-saw rollers 16, 16′. The inner flat side 38, on the other hand, is the inner side of the band-saw blade 14 facing the band-saw rollers 16, 16′.

[0071] It is understood that the two flat sides 36, 38 of the band-saw blade 14 are typically wider than the two narrow sides 30, 32.

[0072] In addition to the band-saw 12, FIGS. 1 and 4 further show the device 10 for automated mounting and dismounting the band-saw blade 14. The device 10 has a support frame 40, which in turn is suspended from a support structure 42 in the carrier structure embodiment shown here. The support structure 42 enables the support frame 40 to be moved along three axes, which are designated x, y and z in FIG. 1. For this purpose, the support structure 42 has a horizontal guide rail 44 extending along the x-axis, on which a carriage 46 is longitudinally displaceable. An arm 48 aligned in the z-direction is mounted on the carriage 46. This arm 48 is preferably an arm which can be moved along the z-axis and is used for positioning in the z-direction. A cantilever beam 50 is arranged at the lower end of this arm 48 (see FIGS. 2 and 3), which serves for positioning in the y-direction. The cantilever beam 50 is preferably designed as a movable or telescopically extendable cantilever beam.

[0073] The support frame 40 is mounted on the free end of the cantilever beam 50. The support frame 40 is thus almost freely movable in all three spatial directions x, y and z, so that it can be positioned relatively easily in relation to the band-saw 12.

[0074] Preferably, the support frame 40 can also be rotated about the y-axis. A corresponding actuator is preferably provided in the cantilever beam 50 for this purpose.

[0075] A plurality of retaining elements 52 are arranged on the support frame. These retaining elements 52 are preferably actively controllable actuators that are configured to temporarily adhere to the outer flat side 36 of the band-saw blade 14 at various points along its contour and thereby exert an outwardly directed tensile force on the outer flat side 38. For this purpose, the retaining elements 52 may each comprise a vacuum lifter, a magnet, or a temporarily sticking retaining element that can be activated in response to temperature, by way of example.

[0076] The retaining elements 52 are distributed on the support frame 40 (see, for example, FIG. 5). In the present exemplary embodiment shown, a total of eight such retaining elements 52 are arranged on the support frame 40. Three of the retaining elements 52 are arranged on each of the two opposing straight sections 54, 54′. Two further retaining elements 52 are arranged on one of the two arcuate sections 56 connecting the two straight sections 54, 54′ (see FIG. 1). It is to be understood, however, that the total number of eight retaining elements 52 is to be understood merely as an example. Of course, more than eight retaining elements or even fewer than eight retaining elements 52 may be arranged on the support frame 40. Preferably, at least one retaining element 52 is arranged in each of the three aforementioned sections 54, 54′, 56 of the support frame 40. This enables a reasonably uniform expansion of the band-saw blade 14 in almost all of its sections 22, 24.

[0077] In the exemplary embodiment example shown here, the support frame 40 is “open on one side”. In this case, no retaining elements 52 are arranged on the second arcuate section 56′. This second arcuate section 56′ of the support frame 40 is positioned in the region of the upper or lower band-saw roller 16, 16′ during the mounting or dismounting process of the band-saw blade 14. In one of the two areas, retaining elements 52 are not necessarily required.

[0078] The operation of the band-saw blade changing device 10 and the sequence of the method are explained below with reference to FIGS. 4-8. These show chronologically several states during the mounting of the band-saw blade 14. Thus, FIGS. 4-8 show in sequence several states during the mounting of the band-saw blade 14 on the band-saw 12.

[0079] FIGS. 4-6 show different views of one and the same condition in which the band-saw blade 14 to be mounted rests on a band stand 58. This band stand 58 is shown here merely by way of example as a possible way of supporting an unused band-saw blade 14.

[0080] In a first mounting step, the support frame 40 is moved towards the band-saw blade 14 arranged on the band stand 58 with the aid of the support structure 42. As soon as the support frame 40 is correctly positioned above the band-saw blade 14 with the aid of the three movable axes x, y and z, the retaining elements 52 are activated. The band-saw blade 14 thereby adheres to the retaining elements 52 and is then at least temporarily connected to the support frame 40.

[0081] Then, the support frame 40 is moved together with the band-saw blade 14 attached to it by means of the support structure 42. This condition is exemplarily shown in FIG. 7.

[0082] In the next step, the support frame 40 together with the band-saw blade 14 is pushed over the band-saw rollers 16, 16′ of the band-saw 12. For this purpose, one of the two band-saw rollers 16, 16′ is preferably moved in the direction of the other in order to reduce the distance between the two band-saw rollers 16, 16′. The support frame is swiveled into the angle α of the band-saw 12 with the aid of the rotatable cantilever beam and then also pushed over the band-saw rollers 16, 16′ along the y-axis with the aid of the cantilever beam 50.

[0083] Once the band-saw blade 14 is correctly positioned on the band-saw rollers 16, 16′, the retaining elements 52 are deactivated, causing the retaining force on the band-saw blade 14 to decrease and the band-saw blade to come to rest on the band-saw rollers 16, 16′.

[0084] The band-saw blade changing device can then move back to its starting position, which is shown in FIG. 6. By moving the two band-saw rollers 16, 16′ apart, the band-saw blade 14 can then be tensioned again on the band-saw rollers and is then ready for operation.

[0085] It is understood that the dismounting operation, in which the band-saw blade 14 is removed from the band-saw 12, is performed in reverse order. First, the distance between the two band-saw rollers 16, 16′ is reduced. Then the device 10 is moved towards the sawing machine 12, pivoted to angle α and pushed over the band-saw blade 14. Then the retaining elements 52 are activated and the support frame together with the band-saw blade 14 is moved away from the band-saw 12 and moved to the storage place or band stand 48, respectively. There, the retaining elements 52 are deactivated again in order to deposit or suspend the band-saw blade 14 on the band stand 58.

[0086] Removing the tension of the band-saw blade 14, i.e. the reduction of the distance between the two band-saw rollers 16, 16′, can take place during the dismounting process both before and after the retaining elements 52 have been activated. If the band-saw blade 14 is only relaxed after the retaining elements 52 have been activated, this may under certain circumstances facilitate the process of the retaining elements 52 adhering to the band-saw blade 14.

[0087] The aforementioned interchangeability of the sequence of these two method steps applies equivalently to the mounting process. Here, too, it is possible to first tension the newly mounted band-saw blade 14 on the band-saw 12 and only then deactivate the retaining elements 52. Alternatively, the retaining elements 52 may be deactivated during the mounting process after the band-saw blade 14 has been mounted on the band-saw 12, but before the band-saw blade 14 is tensioned.

[0088] It is understood that FIGS. 1-8 show only one exemplary embodiment of the device 10 according to the invention. Various modifications thereto are possible without departing from the scope of the present invention as defined in the appended claims. For example, it is not necessary to move the support frame 40 by means of a support structure 42 movable along three axes. Movability along two axes may be sufficient. Also, a suspended construction of the support frame 40 or the support structure 42 is not necessarily required. The support frame 40 could just as well be movable on rollers on the floor. The support frame 40 could also be moved manually (by hand) or with the aid of a robot.