GUIDE FOR USE IN A GRINDING DEVICE

Abstract: The invention relates to a guide (1) used in a grinding device, particularly for an abrasive belt grinder, said grinding device being provided with a grinding tool (3) having its travelling direction crosswise to advancing movement (17), for advancing a piece (2) to be worked, whose length to be worked exceeds the width of grinding tool (3), relative to said grinding tool, or alternatively, for advancing a grinding tool relative to a piece to be worked in a manner that the point of contact and the angle of contact between piece (2) to be worked and grinding tool (3) are adjustable. Guide (1) includes a setting portion (4) adjustable in its distance relative to grinding tool (3), said setting portion being in turn provided with an adjusting means (5) which is fitted on either side of grinding tool (3) with at least one support (6) braced against an edge (16) to be worked in a piece to be worked and/or against a separate steering element, said support being adjustable relative to setting portion (4).

Description: Guide for use in a grinding device The present invention relates to a guide for use in a grinding device, particularly for an abrasive belt grind¬ er, the grinding tool of said grinding device having a traveling direction which is crosswise to the advancing movement, for advancing a piece to be worked, whose length to be worked exceeds the width of a grinding tool, relative to a grinding tool, or alternatively, for advancing a grinding tool relative to a piece to be worked in a manner that the point of contact and the angle of contact between a piece to be worked and a grinding tool are adjustable. For example, when grinding the edges of plate-like pieces as described above, a problem is the strength of an abrasive belt since a piece to be worked can easily strike against the belt edge and the belt is destroyed. Particularly, when working the edges of e.g. glass or stone plates, which usually involves the use of valuable diamond-coated abrasive belts, such premature destruction of a belt incurs substantial economic costs. In order to eliminate these drawbacks, an object of the invention is to provide a guide for adjusting the con¬ tact point and contact angle between a piece to be worked and a grinding tool in a manner that it is virtually im¬ possible for a piece to be worked to strike against the edge of an abrasive belt to break or, alternatively, to collide with the side edge of an abrasive disc. Another object of the invention is to provide a guide for pre¬ cisely controlling the amount of material to be removed. These objects are solved according to the invention by providing a guide which comprises a setting portion ad- justable in its distance relative to a grinding tool, said setting portion being provided with an adjusting means which is fitted on either side of the grinding tool with at least one support braced against the edge to be worked in a piece to be worked and or against a separate steering element, which support is adjustable relative to the setting portion. The adjusting means for controlling the contact angle between a workpiece and a grinding tool is in one pre¬ ferred embodiment of the invention arranged in a man¬ ner that the adjusting means comprises a body portion journalled to be rotatably adjustable relative to an axle which is fixed relative to the setting portion, said supports being mounted on that body portion. Thus, the adjustment of said adjusting means is effected by means of a setting screw and a spring. The setting portion for regulating the quantity of mate¬ rial to be removed is in one preferred embodiment of the invention arranged in a manner that said setting portion is made adjustably rotatable relative to an axle which is fixed relative to the grinding device. Thus, the adjustment of said setting portion is effect¬ ed by means of a setting screw and a spring. The supports mounted on the adjusting means and braced against the edge to be worked in a piece to be work¬ ed and/or against a separate steering element are posi¬ tioned on a common straight line. The support can be a sliding surface, a rotatably journalled roller or a like. The support may have a sliding surface, a roller or a like that can be made removable, whereby the necess¬ ary bracing can be readily varied according to dimensions and conf gurations of a piece to be worked. The invention will now be described in more detail with reference made to the accompanying drawing, the sole figure thereof showing in a diagrammatic plan view the operation of a guide of the invention in a case where a piece to be worked is advanced relative to a station¬ ary grinding device. Referring to the accompanying figure, reference numeral 14 generally designates a grinding device provided with a shaft 15 for driving a grinding tool 3 indicated by reference numeral 3. The grinding tool 3 can be e.g. an abrasive belt fitted on top of an elastic drum or a belt rotating on two reversing wheels. The grinding tool can also be a fixed abrasive disc or a disc having only its cylindrical surface provided with abrasive components. A guide used in the grinding device is generally indi¬ cated by reference numeral 1. Guide 1 is provided with a setting portion 4 which is adjustable in its distance relative to grinding tool 3 and which, in the enclosed figure, comprises a rectangular profiled pipe. The setting portion 4 is provided with an adjusting means 5 which in the traveling direction of a piece 2 to be worked on either side of grinding tool 3 is fitted with at least one support 6, braced against a machinable edge 16 in the piece to be worked and being adjustable relative to setting portion 4. In the illustrated embodiment, said setting portion 4 is arranged to be adjustably rotatable relative to an axle 7 which is fixed relative to grinding device 14. The adjustment is effected by turning a setting screw 11. On the other hand, a spring 12 makes sure that said setting portion 4 is continuously pressed against setting screw 11. The adjusting means 5 is journalled relative to setting portion 4 through the intermediary of an axle 8 which is fixedly fitted in setting portion 4 parallel to axle 7. In order to rotate adjusting means 5 relative to axle 8, said setting portion 4 is provided with a set¬ ting screw 9 as well as a spring 10 for making sure that adjusting means 5 is always pressed against setting screw 9. The plate-like adjusting means 5 has a body portion 5a fitted inside a profiled pipe of setting portion 4 in a manner that said supports 6 mounted on body portion 5a and extending perpendicularly therefrom are placed on both sides of grinding tool 3. The figure illustrates four supports 6. The supports 6 are laid on a common straight line and dimensioned to extend against the edge of a piece 2 to be worked. The support 6 can com¬ prise a sliding surface, a rotatably journalled roller, as shown in the figure, or a like. The setting portion 4 is provided with a number of conveyor rollers 13 for facilitating the advance of workpiece 2. The rollers can be arranged in one or a plurality of rows, also outside said setting portion 4. Rollers 13 can be driving or idling. When operating guide 1 , the grinding of a piece to be worked is effected as follows. A piece to be worked is laid upon rollers 13 on top of setting portion 4 as well as upon rollers, not shown, external of setting portion 4. An edge 16 to be worked in workpiece 2 is placed against support rollers 6 on the fight-hand side of grinding tool 3 in the figure. This is followed by advancing piece 2 in the direction of an arrow 17 relative to grinding tool 3 while main¬ taining said piece 2 continuously pressed against sup¬ port rollers 6, whereby it is also tangential with sup¬ port rollers 6 on the left-hand side of grinding tool 3. An angle &> between the machined edge of workpiece 2 and the working surface of grinding tool 3 is set by adjusting said setting screw 9 of adjusting means 5 in a manner that the distance between workpiece and grind¬ ing tool 3 is longer on the right-side than on the left- hand side of the figure. Thus, said piece 2 always finds the abrasive surface of grinding tool 3 instead of the edge of a grinding tool, the latter resulting in the destruction of a grinding tool. This is followed by determining the amount of removed material by turning said setting screw 11 of setting portion 4. By the proper adjustment of both setting screws 9, 11 the entire abrasive surface of grinding tool 3 can be effectively utilized without a hazard of piece 2 strik¬ ing against the edge of grinding tool 3. The invention is described above with reference made only to one of its preferred embodiments, wherein a piece 2 to be worked is advanced relative to a station¬ ary grinding tool 3. It should be appreciated, however, that a guide of the invention can also be operated by advancing a grinding tool relative to a stationary work- piece. Hence, if desired, it is also possible to use a separate steering element, in which case the supports of an adjusting means are pressed against this steering element for the duration of working. Thus, the edges of a piece to be worked secured parallel to a steering element can be made straight (or to conform to the shape of a steering element) regardless of the standard of a preliminary working effected on a piece to be worked. It is also obvious of course that a guide of the inven¬ tion can be used in grinding devices, in which the grind¬ ing is effected by the frontal surface of a disc.

Claims: Claims 1. A guide (1) for use in a grinding device, particular¬ ly for an abrasive belt grinder, said grinding device being provided with a grinding tool (3) having a travel¬ ing direction which is crosswise to advancing movement (17), for advancing a piece (2) to be worked, whose length to be worked exceeds the width of grinding tool (3) , re¬ lative to said grinding tool, or alternatively, for ad¬ vancing a grinding tool relative to a piece to be worked in a manner that the point of contact and angle ( o of contact between piece (2) to be worked and grinding tool (3) are adjustable, c h a r a c t e r i z e d in that said guide (1) includes a setting portion (4) adjustable in its distance relative to grinding tool (3) , said setting portion being in turn provided with an adjust¬ ing means (5) which is fitted on either side of grind¬ ing tool (3) with at least one support (6) braced against an edge (16) to be worked in a piece to be worked and(or against a separate steering element, said support being adjustable relative to setting portion (4) . 2. A guide as set forth in claim 1, c h a r a c t e r i z e d in that said setting portion (4) is arranged to be adjust¬ ably rotatable relative to an axle (7) which is fixed re¬ lative to a grinding device (14) . 3. A guide as set forth in claim 1 or 2, c h a r a c ¬ t e r i z e d in that said adjusting means (5) is pro¬ vided with a body portion (5a) journalled to be adjust¬ ably rotatable relative to an axle (8) which is fixed relative to setting portion (4), said supports (6) be¬ ing mounted on the body portion. 4. A guide as set forth in any of claims 1 - 3, c h a r - a c t e r i z e d in that said supports (6) are laid on a common straight line. 5. A guide as set forth in any of claims 1 - 4, c h a r ¬ a c t e r i z e d in that said support (6) is a sliding surface, a rotatably journalled roller or a like. 6. A guide as set forth in any of claims 1 - 5, c h a-r - a c t e r i z e d in that the sliding surface, roller or the like of support (6) is adapted to be removable. 7. A guide as set forth in any of claims 1 - 6, c h a r ¬ a c t e r i z e d in that the adjustment of adjusting means (5) is effected by means of a setting screw (9) and a spring (10). 8. A guide as set forth in any of claims 1 - 7, c h a r ¬ a c t e r i z e d in that the adjustment of setting por¬ tion (5) is effected by means of a setting screw (11) and a spring (12) . 9. A guide as set forth in any of claims 1 - 8, c h a r ¬ a c t e r i z e d in that said setting portion (4) is provided with one or a plurality of conveyor rollers (13) . 10. A guide as set forth in any of claims 1 - 9, c h a r a c t e r i z e d in that said roller (13) is either driving or idling.

Inventors: KANTANEN SAKARI, KANTANEN, SAKARI
Applicants: KANTANEN SAKARI, KANTANEN, SAKARI
Application year: 1989
Main classification: B24B41
IPC codes: B24B9, B24B21, B24B41