DK178006B1 - Grinding tools and apparatus for grinding a surface on plate-shaped workpieces - Google Patents

Abstract

Abrasive tool (2) for grinding a surface of plate-shaped blanks and having a circular abrasive surface (17) for rotation in a plane perpendicular to the axis of rotation of the abrasive tool, and comprising a support member (16) adapted to support a grinding element ( 8), preferably an abrasive paper and having a circular central region corresponding to the abrasive surface (17) and an annular rim area (18) having a cone-shaped surface.

Description

Grinding tools and apparatus for grinding a surface on plate-shaped objects The field of the invention

The present invention relates to a grinding tool for grinding a surface of plate-shaped blanks and having a circular abrasive surface for rotation in a plane perpendicular to the axis of rotation of the grinding tool, wherein the grinding tool comprises a support member adapted to support a grinding element, preferably a grinding paper. , and which bore a circular central area corresponding to abrasive surfaces and one. annular rim region with a cone-shaped surface, the cone-shaped rim region forming an angle between 3 and 25 °, preferably between 5 and 10 ° with the abrasive surface.

The invention further relates to an apparatus for grinding a surface of plate-shaped blanks and comprising a conveyor unit with a support plane of the blanks and a supporting arrangement with a number of grinding tools arranged above the conveyor unit supported on an endless conveyor body for guiding the grinding tools in a circular manner. movement parallel to the support piano, each of which abrasive tools arranged for rotation about an axis perpendicular to the uncler support piano and with a circular abrasive surface for rotation in a plane perpendicular to the axis of rotation of the abrasive tool in a plane parallel to the support plane.

The invention also relates to the use of such a tool in such an apparatus. Background of the invention

In industrial grinding of plate-shaped workpieces comprising edges, rounds and surfaces, for example countertops, different types of grinding devices are used which can grind the whole workpiece as a passage through the grinding machine. In order to achieve a nice surface, it is important that the grinder does not leave clear marks after the grinding direction.

For example, abrasives are provided with a plurality of rollers either with wrapping abrasive paper or with a plurality of abrasive elements located along the longitudinal direction of the roll.

To prevent the grinding direction of the rollers from being the same, the grinding apparatus is formed with either rollers which typically rotate opposite each other or rollers which are set at different angles to the surface.

The disadvantage of these types of rollers is that they use a large amount of abrasive paper, whereby the abrasive paper often has to be replaced. This results in production stoppages and increases the cost of grinding.

Furthermore, the abrasive paper will not be worn evenly along the roller, especially if items of different dimensions are to be sanded. The abrasive paper will typically be worn most on the middle part of the roller.

WO99 / 22905 and EPO 471 641 disclose another type of grinding apparatus wherein a plurality of rotating rollers are positioned about a vertical shaft connected to a drive unit so that the rollers, in addition to rotating about their own shaft, rotate therein. horizontal plane around the vertical shaft.

By rotating the roller, around two shafts, you try to avoid clear abrasions. In WO99 / 22905 the rollers rotate in different directions with each other. different speeds.

The disadvantage of this is that the rotating rollers are in the opposite direction of rotation in the horizontal plane. will have a greater abrasive effect than the rollers having an orbit in the same direction as the rotation in the horizontal plane.

In EPO 471 641, a number of abrasive arrangements are used, each shear arrangement consisting of one. number of rotating rollers rotating about a vertical shaft. To ensure grinding of the entire workpiece, these grinding arrangements are arranged with overlap, which causes an uneven grinding as there are areas of the workpiece that are sanded more than once.

The disadvantage of both of the above abrasives is that. they must have long rollers in order to grind wide blanks, which means that the motor units for these rollers must be correspondingly larger. Part results in a higher acquisition cost for the grinder as well as a stone energy consumption.

IUS 2002/00 (58515 discloses a surface treatment apparatus wherein either a grinding drum and / or a drill with an amal circular grinding brush is used for surface treatment of a preferably flat blank and wherein the grinding brushes are shown arranged in two rows offset to each other, so that the second row of abrasive brushes just overlaps the abrasive area of the first row of abrasive brushes.

This construction of the surface treatment apparatus causes an uneven surface treatment as the abrasive areas of the two rows of abrasive brushes overlap slightly and only one surface of the workpiece is sanded.

This means that appliances will not ensure an efficient ais! opening / grinding edges and stripes on a workpiece, for example, a stationary grinding drum can only grind the surface and facing edges / grommets, and a brush with overlap of the grinding area of the grinding brushes ensures only grinding of large parts of the surface once.

Furthermore, a grinding tool for grinding a surface of plate-shaped blanks and having a circular grinding surface for rotation in a plane perpendicular to the axis of rotation of the grinding tool will not be able to grind the blanks which are conveyed in a so-called grinder where the blanks lying on a conveyor belt are inserted. under a boom on which the grinding tools are mounted. The edges of the grinding tool will hit the side edges of the workpieces. Thus, construction is complicated by a height-adjustable boom which is difficult to control. Even in such a situation, it is not possible to grind the items precisely if they have a slight thickness variation.

For flat grinding, it is common to use broadband polishers. However, in practice, it often turns out that these cross strokes on the items being sanded. For topics with. high finish without abrasive traces, it has so far only been necessary to use a manual finishing.

From US 4065882 there is known a grinding tool for use in grinding machines, where the tool is applied to grinding paper having a circular central area which is the active part of the grinding paper and an edge area which is slit. The edge area is adjusted by removing parts from the slit so that it can be folded over the edge of the tool without forming overlap. The border area then forms an active corner or edge.

The disadvantage of this is partly that the abrasive paper has to be adjusted very precisely during slitting to avoid overlap and partly the placement itself, of the abrasive paper on the support member during assembly must be done with great precision.

From Wo 2005/056234 Al is known an abrasive for surface treatment. The apparatus comprises a support means for a series of abrasive heads, each having an abrasive element and a motor driving it. The support means comprises an endless conveyor means for the grinding heads so that. the grinding heads are found in a circular motion parallel to the support member.

The present invention will be particularly useful in such an apparatus. The object of the invention

It is an object of the present invention to provide a simple grinding tool and grinding device that can evenly grind or blend the workpiece with edges, rounds and scrapings without abrasive grooves on the abrasive surfaces and which is easy to use where the workpiece is used. is inserted under the abrasive tool in a direction parallel to the abrasive surface and avoids slitting of the tissue paper.

Description of the Invention

This is achieved according to the present invention with an abrasive tool of the type mentioned initially, characterized in that the support member (16) comprises an elastic abutment member (19) on which the abrasive element (8) is mounted.

The abrasive apparatus according to the invention is characterized in that the abrasive tool comprises a support member comprising an elastic resilient layer (19) adapted to support an abrasive element 'preferably an abrasive paper and having a circular central area corresponding to the abrasive surface and a annular rim area with a cone-shaped surface.

Due to the cone-shaped surface, a grinding tool in a grinding machine will be inserted over the edge of a plate-shaped workpiece while the edge is degraded. The grinding tool provides a high quality grinding result, for example, as borrowed from eccentric grinders. However, by using multiple heads, the circular grinding grooves as known from the use of an eccentric grinder are avoided.

Further, the support means comprises an elastic resilient layer on which the abrasive paper is mounted. This allows adjustment to slightly different thickness of the workpiece and will also allow the workpiece to be sanded with a grinding pressure that can be adjusted by appropriate selection of the resilient resilient layer. Alternatively, the grinding tool may comprise a resilient resilient suspension, preferably an air cylinder.

In a preferred embodiment of the invention, the grinding tool is characterized in that. the cone-shaped rim region forms an angle between 3 and 25 °, preferably between 5 and 10 ° with the abrasive surface. This provides a suitable cooling or inclined surface so that the grinding tool does not bump into the blank of the workpiece but is instead inserted over the workpiece which may have an abutment pressure against the workpiece during grinding.

In a further embodiment of the invention, the grinding tool is characterized in that the resilient layer has a Shore A between 30 and 60, preferably between 40 and 50. In practice, this has been found to give a good result in the grinding.

In a further embodiment of the invention, the abrasive tool is characterized in that the abrasive element comprises abrasive paper which is slit, preferably with largely radially extending slots. This makes the sieve pair more easily adapted to the cone stump at the edge area.

In a further embodiment of the invention, the abrasive tool is characterized in that the abrasive element is provided with holes and that corresponding holes are provided in the abrasive suction suction support means. In a further embodiment of the invention the abrasive tool is distinctive, border area is between 10 and 17 min wide and has an increase between 2 and 5 mm. This is typically used in a grinding tool with a diameter between 100 and 180 spaces preferably around the ISO.

In a further embodiment of the invention, the grinding tool is characterized in that it comprises a motor. Hereby, each tool can be rotated in one direction or another independently of other tools in an apparatus.

These abrasive tools are connected to the support arrangement which holds the abrasive tool in a desired position relative to the surface of the workpiece. Hereby, a large number of tools can be used in a simple way in a machine, for example a pass-through grinder.

The abrasive tools are circular and have support means which support abrasive discs »and which are connected to the abrasive blemishes, so that the abrasive disks in use are placed parallel to a surface of the workpiece which is to be cut. preferably sanded in a horizontal plane.

In order to be able to grind the whole workpiece at one pass, the carrier arrangement comprises an endless conveying means for said grinding heads, which conveyor is driven by a moving motor.

As a result, the individual grinding tools, in addition to being able to rotate about their own vertical shaft, can be moved horizontally across the workpiece passing through the apparatus resting on the support plane. The umler support plane may be formed by a conveyor belt or by ruffles / rollers or any other conveyor ex. support and transport the items through the grinder. Grinding the horizontal movement of the tools across the workpiece takes place in a direction perpendicular to the vertical axis of the sieve elements. This ensures that the entire workpiece is sanded at one pass through the grinder.

As the lance rail is an endless web which causes the grinding heads to move around from one side to the opposite side and back again to the first side, so that the workpiece is surface treated by two rows of sii tools which are passed over through the sieve apparatus. the subject in opposite directions.

In this way, a very smooth grinding of the workpiece is achieved, as the second row of grinding heads will typically grind in the opposite direction, thereby removing any grinding grooves that have occurred from the grinding performed by the first row of grinding heads.

Thus, in a grinding apparatus, the downward movement of the rotary grinding tools will cause a grinding which has been found to provide a surprisingly finely sanded surface without leaving grinding grooves.

Thus, a workpiece can only be ground one passage of a grinder. If desired, the sander can form part of a machine made with several serially mounted grinders. In such a machine, the sander according to the invention will constitute the last sander in the machine.

It is preferred that each tool be driven by its own engine. This makes it possible to have the same or different direction of rotation for each grinding tool in an apparatus. This can. 1 is controlled by a control unit.

For example: every other grinding tool can have the same direction of rotation, while the intermediate grinding tools have an opposite direction of rotation, or every third grinding tool can have the same direction of rotation, while the intermediate grinding tools have an opposite direction of rotation.

The different rotational directions of subsequent grinding tools mean that the sander can advantageously be used for excavating and grinding edges and stripes.

The lateral movement of the grinding tools must be aligned with the speed at which the workpiece is passed through the grinder, so that the grinding tools are moved at least so fast that the workpiece receives at least two grinding and so that there are no areas on the workpiece that do not grind. .

In order to move the abrasive tools across the conveying direction of the workpiece through apparatus, said conveying means is comprised of a plurality of drive chains or belts adapted to engage a drive wheel driven by said moving motors.

In a preferred embodiment of the invention, four of these drive wheels are located rectangular! in the support frame so that grinding tools connected to the conveying means are first moved across the workpiece and then back across the workpiece.

If the transport means is a drive chain, the drive wheels will be gears that engage the drive chain, thereby driving the transport means with grinding heads around.

If the conveyor is a drive belt in the form of a V-belt, the drive wheels will be either smooth drive wheels which, by means of the resistance between the V-belt and the drive wheel, will drive the transport means with the grinding tools, or a gear drive which engages a toothed side of the V-belt.

Alternatively, the conveyor means may be wires or wide baud or the like, the drive wheel being a narrow drive wheel or roller, respectively.

Instead of having the drive wheels mounted rectangularly in the support frame, the drive wheels may be conceived in other polygonal arrangements such as: - three drive wheels placed in a triangle, or - five drive wheels located in a pentagon.

Alternatively, only one can be used. two drive wheels about which the conveyor is driven so that the two rows of grinding tools are located immediately after each other. This requires that the grinding tools must not be too large in diameter, since otherwise the grinding tools cannot pass each other across the workpiece.

The! will be advantageous in that the two rows of grinding tools move across the workpiece at some distance, since there is time and space for the grinding material from the first row of tools to be moved away from the workpiece, for example by suction and thus does not prevent the second row of grinding heads from performing an optimal grinding. For example, drilling suction can be done through rollers or rollers on which the workpiece rests when passing through the machine.

Instead of having drive wheels connected to a moving motor in all corners of the support frame, a tiel of these drive wheels may be idler wheels located only to guide the conveyor.

In a preferred embodiment. of the invention, the conveyor means is a wide toothed belt running around two large gears located with a gear in each side of the grinding ape parai. On the toothed belt, the grinding tools are located.

Since an abrasive apparatus must be capable of being used for items of different thickness, it comprises an apparatus frame in which said support arrangement is height adjustably arranged by a plurality of shear energizers.

Since the support frame with abrasive heads has a considerable weight, a number of displacement energizers are used to raise / lower the support frame in the apparatus frame.

This means that the support frame can be placed at a set height in the apparatus frame, whereby grinding tools are placed so that they grind an exact thickness of the workpiece.

The shear forces may be cylinders, rack / pinion arrangements, mechanical tilt arrangements, rotational arrangements or the like, which may be hydraulically driven, pneumatically or electrically driven.

As the support frame can be height adjusted, it is easy to raise the support frame to a height where it is easy to replace abrasive tools or abrasive tools in the tools.

The abrasive elements may be made of abrasive paper mounted on a support member, for example by means of Velcro surfaces, or otherwise which allows a rapid replacement of the abrasive elements.

The support member may be hinged with a hub / pin, which may be connected to the shaft motors shaft, for example by screw mounting, bayonet mounting, spring locking or otherwise enabling fast mounting / disassembly.

In these ways, the grinding elements and / or grinding tools can be changed quickly and easily, so that it is not necessary to. have long production stops when replacing grinding elements or grinding tools.

An abrasive apparatus of the present invention may be used in the wood industry, but that sex may also be used in other industries where there are surfaces to be sanded, for example in the automobile industry where plate parts for vehicles are to be sanded.

Thought description

The invention will then be explained in more detail with reference to the accompanying drawing, in which fig. 1 is a perspective view of a grinder according to the invention; FIG. 2 is a sectional view of the grinder of FIG. 1, FIG. 3 is a side view of the grinder of FIG. 1, light. 4 shows a further side view of the grinder of FIG. .1, fig. 5 is a perspective view of a grinding head with grinding tool; FIG. 6 shows an alternative support frame; FIG. 7 shows a grinder; FIG. 8 is a side view of the abrasive support member; and FIG. 9 shows another side view of the abrasive support member.

Detailed description of the invention

Figures 1-7 describe an apparatus as contained in WO 2005/056234 A1.

In FIG. 1 * 4 is shown an abrasive apparatus 1 comprising a plurality of abrasive heads 6 embossed in an abrasive motor 3 and an abrasive tool 2 with associated abrasive support 16 and abrasive element 8.

Each grinding head 6 is suspended in the support frame 4 along a conveyor member 9 with a plate portion 14.

Conveyor member 9 is arranged to engage drive wheels IL driven by lifting motors 5.

In the illustrated embodiment of the grinding apparatus 1, there are two drive wheels 11 and two running wheels 10 which are placed rectangularly so that the grinding heads 6 are moved perpendicularly across a feed direction (not shown) A. Drive wheels 11 are located in opposite corners of the support frame 4 .

The conveyor 9 is shown as two chains engaging an upper and lower set of drive wheels Ϊ 1a, 1 lb / idler wheels 10a, 10b, respectively, shown as gears.

In order to keep the grinding heads 6 in a vertical position so that the grinding elements 8 are parallel to the surface of the workpiece (not shown), the device sleeve 7 is provided with a wire / band 13 which prevents the grinding heads 6 from seaming to the side.

The carrier anime 4 is connected to the apparatus frame 7 via drive wheels 11 / idler wheels 10 and frame part 15 and is height adjustable by means of cylinder 12.

FIG. 5 shows a grinding head. 6 with associated grinding tool 2 driven by a motor 3. The grinding head is located on a plate 21 which forms the connection between the grinding head 6 and the support frame (not shown).

Fig. 6 shows one. alternative carrier frame 4 on which a plurality of abrasive heads 6 are arranged, on an endless conveyor member 9, shown here as a wide toothed belt. There. endless conveyor means 9 is driven by a moving motor 5 so that the grinding heads 6 move around the support frame 4, while the motors 3 of the grinding heads 6 rotate the support grinding tools 2. The individual grinding tools 2 are thereby moved in an epicyclic motion.

FIG. 7 shows an abrasive apparatus 1 with a transport unit 24 for supporting and optionally feeding a plate-shaped blank to be machined. A carrier arrangement 4 is suspended above the transport unit, in which a number of abrasive tools 2, guided by an endless transport means 9, in a circular motion.

FIG. 8 shows a grinding tool with abrasive element 8 mounted. The inner circular area constitutes the abrasive surface 17 which is in contact with the workpiece. Outside the abrasive surface 17, there is an annular rim area 18 which is formed with a waving! relative to the abrasive surface 17 to form a cone stub. In the illustrated embodiment of the grinding tool, a number of slots 26 are located in the grinding element 8, in addition to a number of holes 22 for extraction of grinding dust.

FIG. 9 shows the support member 16 with abrasive element 8 mounted. The abrasive member 8 is secured by velcro surfaces, double-adhesive tape or otherwise attached to the support member 16. The support member, in the embodiment shown, consists of a hard portion 27 and an elastic resilient layer 19 on which the abrasive member is located. The support means is provided with a collar 28 or the like, which allows fastening, of the grinding tool 2 to a shaft on a grinding head (not shown). In the illustrated embodiment, the grinding element 8 is provided with a number of holes 22 and the support member 16 is provided with corresponding holes 23 for extraction of grinding dust.

Claims (7)

Abrasive tool according to claim 1, characterized in that the resilient layer (19) has a Shore A between 30 and 60, preferably between 40 and 50. Abrasive tool according to claim 1 or 2, characterized in that the abrasive element (8) comprises abrasive paper which is slit, preferably with largely radially extending slots (26). Grinding tool according to any one of the preceding claims, characterized in that the grinding element (S) is provided; with holes (22) and corresponding holes (23) are provided in the abrasive dust removal means (16). Grinding tool according to any one of the preceding claims, characterized in that the peripheral area (18) of the support member is between 10 and 17 mm wide and has an increment of between 2 and 5 mm. Grinding tool according to any of the preceding clay pits, characterized in that it comprises a motor (3). Apparatus (1) for grinding a surface of plate-shaped blanks and comprising a transport unit (24) having a support plane of the blanks and a supporting arrangement (4) with a number of grinding tools arranged above the transport unit supported on an endless conveyor means (9) for guiding the abrasive tools (2) in a circular motion parallel to the support plane £, each of which abrasive tools (2) being adapted for rotation about an axis perpendicular to the support plane and having a circular abrasive surface for rotation in a plane perpendicular on the axis of rotation of the grinding tool in a plane parallel to the miter support tab, wherein the grinding tool (2) comprises a support member (16) adapted to support a grinding element (8), preferably a grinding paper and having a circular central area corresponding to the grinding surface (17). and an annular rim region with a cone stub-lined rim region (18) forming an angle between 3 and 25 °, preferably s between 5 and 10 ° with the abrasive surface (17), characterized in that the support member (16) comprises an elastic resilient layer (19) on which the abrasive element (8) is mounted. Use of a grinding tool (2) according to any of lira veins 1-6 in an apparatus (1) according to claim 7.