DE202016106358U1 - Grinding device and grinding system - Google Patents

Abstract

Grinding device comprising a grinding machine (12) with a rotatably driven sanding pad (14) on which a grinding wheel (30) is detachably mounted, wherein the sanding pad (14) at least one suction opening and the grinding wheel (30) a plurality of through holes (34) for sucking Having grinding dust through the grinding wheel (30) to the sanding pad (14), characterized in that between the sanding pad (14) and the grinding wheel (30) a disc-shaped intermediate element (20) with at least one lateral recess (24) is arranged, which a through hole (34) in the grinding wheel (30) extends to a suction opening, wherein a laterally open suction channel (26) in the intermediate element (20) is formed.

Description

The invention relates to a grinding device with a grinding machine with a rotatably driven grinding disc, to which a grinding loop is detachably attached, wherein the grinding disc at least one suction opening and the grinding wheel have a plurality of through holes for sucking grinding dust through the grinding wheel to the grinding disc, according to the preamble of claim 1 ,

The invention further relates to a grinding system with a robot arm according to claim 6.

A generic grinding device is from the EP 2 842 689 B1 known. On a rotating sanding pad a grinding wheel is detachably attached. In the grinding wheel through holes are arranged through which sanding dust is sucked to one or more suction openings on the rotating driven grinding plate in grinding operation.

After a certain period of operation, the grinding device is arranged in a changing device. In the changing device, picking fingers engage in undercut recesses on the sanding pad. With the picking fingers, the grinding wheel is clamped to a holding plate. In this tensioned position now the sanding pad can be moved, with a Velcro connection between the grinding wheel and the sanding disc dissolves. Subsequently, a new grinding wheel can be applied to the sanding pad and the grinding process can be continued.

For the retraction of the acceptance finger into the recesses and the clamping numerous adjusting cylinders are required.

From the US 2015/0020369 A1 a manual grinding device is known in which a sanding plate is provided with lateral recesses. In the area of the lateral recesses a drain hole is mounted in the grinding wheel. By hand, the sanding pad is moved to a pick-up hook, which engages from behind into the vent hole on the grinding wheel. Then, the sanding pad can be removed by hand from the grinding wheel, the grinding wheel remaining on the pick-up hook.

In grinding mode, grinding dust also passes through the vent holes and may accumulate on the sanding pad at the back of the grinding wheel. The grinding dust can accumulate to lumps, which can reach the grinding surface again in grinding operation and can lead to undesirable grooves in the surface to be ground.

The invention has for its object to provide a grinding device and a grinding system, with which both a high-quality grinding and an efficient removal of the grinding wheel are made possible by the grinding disc.

The object is achieved according to the invention by a grinding device with the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims.

The grinding device according to the invention is characterized in that a disc-shaped intermediate element is arranged between the grinding disc and the grinding wheel with at least one lateral recess, which extends from a through hole in the grinding wheel to a suction, wherein a laterally open suction channel is formed in the intermediate element.

A basic idea of the invention is to provide a draw-off hole on a grinding wheel in a grinding device for a simplified removal, but to largely avoid the problem of accumulation of grinding dust and the associated danger of scoring during grinding operation. This is achieved according to the invention in that the suction or drain hole and the associated lateral recess a suction opening is assigned to the sanding pad, wherein a laterally open suction channel is formed. Even if the suction channel is open at the side, a sufficient negative pressure can be generated thereby, by means of which grinding dust in the area of the passage or withdrawal hole is sucked back into the sanding plate and removed. Thus, an accumulation of sanding dust at the passage or vent hole and thus a risk of scoring is avoided or greatly reduced. The grinding wheel can be solved in a simple way with a pick-off hook. Elaborate actuating cylinder in the exchange station can be omitted.

With a removal of the grinding wheel by a pickup hook, there is thus no or hardly any grinding dust on the back of the grinding wheel. As a result, a dust load of the ambient air is reduced. This reduces the expense of an exhaust air system and increases occupational safety.

An improved dust removal is achieved according to a development of the invention in that the disc-shaped intermediate element made of an elastic, compressible material, in particular a foam is formed and that the compressible intermediate element is compressed in the grinding operation when it rests against a surface to be ground. By an elastic, compressible configuration of the disc-shaped intermediate element, which preferably has a thickness of 5 mm to 30 mm in the unloaded state, the thickness is considerably reduced in the grinding operation. Preferably, with an applied grinding pressure, the thickness of the intermediate element is reduced to half or even more. This shortens the laterally open suction channel. Consequently, the through hole at one end of the suction channel and the suction opening at the other end of the suction channel are closer to each other, whereby the effect of suction of grinding dust increases accordingly. At the same time when changing the grinding wheel, the intermediate element is relieved after removal of the workpiece to be ground, so that the intermediate element assumes its original thickness again. In this case, the open suction channel can serve to receive a pickup hook.

According to one embodiment of the invention, it is provided that the through hole is formed in the grinding wheel on the laterally open suction channel for the passage of a pickup hook. Preferably, the through hole, which is provided as a drain hole, a sufficient distance from the free edge of the grinding wheel. As a result, a tearing of the grinding wheel is avoided, thus ensuring a reliable decrease.

In principle, only a single through-hole can be provided on the grinding wheel as a draw-off hole for forming a single open suction channel. It is particularly advantageous according to a development of the invention that a plurality of lateral recesses are arranged in the disk-shaped intermediate element, wherein a plurality of laterally open suction channels are formed. Preferably, three, four or more suction channels are provided on the grinding device. This facilitates handling when removing the grinding wheel. The removal can be done manually or preferably automatically.

It is particularly advantageous according to a further embodiment of the invention that a grinding wheel is provided with a standard hole pattern. This is inexpensive to procure and ensures good dust extraction. It is only the intermediate element and / or the sanding pad once to adapt.

The invention further comprises a grinding machine having a robot arm to which is mounted a grinding device as described above. In particular, the grinding system with a robot arm can perform an automatic grinding operation including an automatic grinding wheel change. The robot arm is part of a multi-joint robot with numerous joints and adjustment possibilities in the room.

A preferred embodiment of the grinding system according to the invention consists in that a suction unit is provided for sucking off grinding dust by the grinding plate. The sanding pad has one or more suction openings, through which sanding dust can be sucked off in a sanding operation to a rear suction unit via a suction line. The suction unit may have a vacuum pump for generating a defined negative pressure. The suction unit may in particular be provided with a filter device for separating the abrasive particles from the extracted air.

A further advantageous embodiment of the grinding system according to the invention is that a changing device is arranged for changing the grinding wheel. The changing device or changing station can be designed to automatically change the grinding wheel. For this purpose, a removal device is initially provided with the Abnahmehaken. In principle, the pick-off hook can also be mounted adjustably. Preferably, however, the pick-up hook is stationary, wherein for changing the grinding wheel with the sanding pad is preferably moved via a robot arm to the pickup hook.

In addition to the removal device, the changing device or changing station can have a device for applying a new grinding wheel. In this case, the grinding wheel is held with the intended hole pattern positionally accurate at a transfer position. The sanding pad is adjusted and can thus record the grinding wheel accurately with a predetermined rotational position, so that the through holes in the grinding wheel correspond to the suction openings in the sanding pad.

It is preferred that the changing device has at least one pick-off hook, which engages in a through hole on the laterally open suction channel. In principle, it is also possible for a plurality of detachment hooks to be provided, which preferably engage at the same time in corresponding passage or withdrawal holes in the grinding wheel.

According to a development, a particularly efficient removal of the grinding wheel is achieved in that the pick-up hook is directed downwards, so that when shearing the grinding plate from the grinding wheel, the grinding wheel is held on the pick-up hook and after removal of the grinding disc the grinding wheel falls by gravity downward from the pick-up hook. This allows efficient disposal of the used grinding wheel.

It is particularly preferred according to a development of the invention that a collecting container for grinding wheels is arranged below the pickup hook. This picks up the falling grinding wheels and can be emptied at regular intervals.

In principle, the invention also encompasses a grinding process which can preferably be carried out with the abrading device described above or with the abrading device described above. In this case, a grinding wheel is removably attached to a sanding plate, wherein the sanding pad at least one suction opening and the grinding wheel have a plurality of through holes for sucking sanding dust through the grinding wheel to the sanding pad. Between the grinding disc and the grinding wheel, a disc-shaped intermediate element is arranged with at least one lateral recess, which extends from a through hole in the grinding wheel to a suction opening, wherein a laterally open suction channel is formed in the intermediate element, by which grinding dust from the through hole at the lateral recess is sucked to the sanding plate.

The invention will be further described below with reference to a preferred embodiment, which is shown schematically in the accompanying drawings. In the drawings show:

1 a schematic partial side view of a grinding device according to the invention;

2 a perspective view of a portion of the grinding device according to the invention;

3 a perspective view of an intermediate element for a grinding device according to the invention; and

4 a plan view of a grinding wheel for the grinding device according to the invention.

According to 1 has a grinding device according to the invention 10 a basically known grinding machine 12 which is preferably attached to a robot arm of a grinding system. This grinding system with a robot arm is basically the same or similar to the grinding system according to the EP 2 842 689 B1 built, which also comes from the applicant. Due to the different structure of the grinding device 10 the exchange station is simplified compared to the Applicant's European patent mentioned, as will be explained below.

The grinding machine 12 has a rotationally driven, preferably eccentrically rotating driven grinding plate 14 on. At the circular disc-shaped sanding pad 14 is via a disk-shaped intermediate element 20 a grinding wheel 30 releasably secured. In grinding mode is the grinding wheel 30 to change ring in a change station, which according to the invention with a pick-up hook shown schematically 40 is provided.

The disk-shaped intermediate element 20 is formed of a flexible, elastic material, in particular of a foam material. The intermediate element 20 can thus be applied in grinding operation with pressure on a workpiece to be ground, with the flexible grinding wheel 30 by deformation of the intermediate element 20 can cling well to the surface to be sanded.

As synonymous with 4 is shown in more detail, the grinding wheel 30 a flexible body 32 , about from a reinforced 21 Paper or textile material. In the main body 32 are through holes at regular intervals 34 introduced according to a given standard hole pattern. The through holes 34 in the grinding wheel 30 essentially correspond with channel-like holes 22 in the intermediate element 20 , The holes 22 extend from a top 21 to a bottom of the intermediate element 20 , as clearly in 3 is shown. A top of the grinding wheel 30 is provided with an abrasive grain. A back of the grinding wheel 30 is provided with a fastening material, such as a Velcro coating. With this Velcro coating, the grinding wheel 30 detachable on a correspondingly shaped top 21 the associated intermediate element 20 be attached to form a releasable Velcro connection.

At two opposite side regions of the circular disk-shaped intermediate element 20 are radially extending side recesses 24 formed, which is up to a channel-like hole 22 in the intermediate element 20 extend. This will be in the intermediate element 20 a laterally open suction channel 26 formed, which of a corresponding through hole 34 on an applied grinding wheel 30 up to a suction opening, not shown, in the bottom adjacent grinding plate 14 extends. The width of the recess 24 is preferably smaller than the diameter of the hole 22 ,

In grinding operation, the intermediate element 20 compressed so that the approximately 1 cm to 2 cm long suction 26 shortened by about half in the grinding operation. Thus, despite the lateral opening through the corresponding through hole 34 and the canal-like hole 22 In this area resulting grinding dust reliably through the intermediate element 20 to the sanding plate 14 be dissipated.

As in the 1 and 2 is indicated, allows the lateral recess 24 the passage of a right-angled Abnahmehakens 40 in a changing station, the grinding wheel 30 at the intermediate element 20 to engage behind from behind. In this case, preferably, a relative movement of the sanding plate takes place 14 with the robot arm to the preferably stationary pickup hook 40 in the change station. By a corresponding lowering of the sanding plate 14 enters the top of the pickup hook 40 through the corresponding through hole 34 in the grinding wheel 30 therethrough. This will be the grinding wheel 30 at the pickup hook 40 held. Now the sanding plate can 14 with the fixed intermediate element 20 be moved away, with the grinding wheel 30 from the top 21 of the intermediate element 20 sheared off and loosened. So can a used grinding wheel 30 in a simple and efficient way in a change station from the sanding pad 14 with the attached intermediate element 20 be replaced. Is the tip of the pickup hook 40 directed downwards, the removed grinding wheel can 30 fall down into a container.

Subsequently, a new grinding wheel, as known from the prior art, placed and the positionally accurate grinding operation can be continued.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2842689 B1 [0003, 0030]
• US 2015/0020369 A1 [0006]

Claims (11)

Grinding device with a grinding machine ( 12 ) with a rotating driven sanding pad ( 14 ), on which a grinding wheel ( 30 ) is releasably attached, wherein the sanding pad ( 14 ) at least one suction opening and the grinding wheel ( 30 ) several through holes ( 34 ) for sucking off grinding dust by the grinding wheel ( 30 ) to the sanding plate ( 14 ), characterized in that between the sanding plate ( 14 ) and the grinding wheel ( 30 ) a disk-shaped intermediate element ( 20 ) with at least one lateral recess ( 24 ), which extends from a through hole ( 34 ) in the grinding wheel ( 30 ) extends to a suction opening, wherein a laterally open suction channel ( 26 ) in the intermediate element ( 20 ) is formed. Grinding device according to claim 1, characterized in that the disc-shaped intermediate element ( 20 ) is formed from an elastic, compressible material, in particular a foam, and that the compressible intermediate element ( 20 ) is compressed in grinding operation when abutting a surface to be ground. Grinding device according to claim 1 or 2, characterized in that the through-hole ( 34 ) in the grinding wheel ( 30 ) at the laterally open suction channel ( 26 ) for the passage of a pick-up hook ( 40 ) is trained. Grinding device according to one of claims 1 to 3, characterized in that a plurality of lateral recesses ( 24 ) in the disk-shaped intermediate element ( 20 ), wherein a plurality of laterally open suction channels ( 26 ) are formed. Grinding device according to one of claims 1 to 4, characterized in that a grinding wheel ( 30 ) is provided with a standard hole pattern. Grinding plant with a robot arm, on which a grinding device ( 10 ) is mounted according to one of claims 1 to 5. Grinding plant according to claim 6, characterized in that a suction unit for extracting grinding dust by the sanding pad ( 14 ) is provided. Grinding plant according to claim 6 or 7, characterized in that a changing device for changing the grinding wheel ( 30 ) is arranged. Grinding plant according to claim 8, characterized in that the changing device at least one Abnahmehaken ( 40 ), which in a through hole ( 34 ) at the laterally open suction channel ( 26 ) intervenes. Grinding plant according to claim 9, characterized in that the pick-off hook ( 40 ) is directed downward, so that when shearing the sanding plate ( 14 ) from the grinding wheel ( 30 ) the grinding wheel ( 30 ) is held on the pickup hook and after removing the sanding pad ( 14 ) the grinding wheel ( 30 ) by gravity downward from the pick-up hook ( 40 ) falls. Grinding plant according to one of claims 6 to 10, characterized in that below the pick-up hook ( 40 ) a collecting container for grinding wheels ( 30 ) is arranged.

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