Transporting apparatus

A transporting apparatus comprises a track (2) and at least one movable element (3) movable along said track (2), said movable element (3) comprising a supporting body (14), said track (2) comprising a first guiding surface (11a) and a further first guiding surface (lib) facing towards said supporting body (14), a second guiding surface (12a) and a further second guiding surface (12b) facing away from said supporting body (14), and a third guiding surface (13a) arranged transversally to said first guiding surface (11a) and said second guiding surface (12a) and a further third guiding surface (13b) arranged transversally to said further first guiding surface (lib) and said further second guiding surface (12b), wherein said movable element (3) comprises a first couple of rollers (15) slidably coupled to said first guiding surface (11a), a further first couple of rollers (16) slidably coupled to said further first guiding surface (lib), a second couple of rollers (17) slidably coupled to said second guiding surface (12a), a further second couple of rollers (18) slidably coupled to said further second guiding surface (12b), a third couple of rollers (19) slidably coupled to said third guiding surface (13a) and a further third couple of rollers (20) slidably coupled to said further third guiding surface (13b).

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This is a National Phase of International Application No. PCT/EP2016/056501, filed Mar. 24, 2016, which claims the benefit of European Application No. 15162524.1 filed Apr. 7, 2015. The entire contents of the above-referenced applications are expressly incorporated herein by reference.

TECHNICAL FIELD

The invention relates to a transporting apparatus for conveying an object. The object may be a device, or a tool, of a machine, in particular a packaging machine.

BACKGROUND OF INVENTION

Transporting apparatus based on linear motor technology are known, which comprise a track that houses a stator armature formed by a plurality of individually-excitable solenoids, and a plurality of movable elements or carts that house respective permanent magnets and are independently moved along the track by individually controlling the solenoids.

The track comprises guide elements and the movable elements comprise wheels slideable along the guide elements of the track.

In case the movable element supports a device, or a tool, of a machine, the position of the movable element with respect to the track has to be extremely precise, in order to assure that the machine works in a proper way.

A drawback of the known transporting apparatus is that there might be an excessive play, or clearance, between the wheels and the guide elements, leading to a mispositioning of the movable elements with respect to the track. In case the transporting apparatus are used in a machine, this may cause a mispositioning of the device, or tool, supported by the movable elements.

DISCLOSURE OF INVENTION

An object of the invention is to improve the known transporting apparatus.

Another object of the invention is to provide a transporting apparatus that has high stiffness and extremely limited play, or clearance.

Another object of the invention is to provide a transporting apparatus that, when used in a machine, is able to carry a tool of the machine and position the tool in a very accurate and precise way.

According to the invention there is provided a transporting apparatus as claimed in claim1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

With reference toFIGS. 1 to 5, there is shown a transporting apparatus1comprising a track2and a plurality of movable elements3movable along the track2.

The track2houses a stator armature formed by a plurality of individually-excitable solenoids101and the movable elements3house permanent magnets102.

The movable elements3are independently movable along the track2by individually controlling the solenoids101.

In another embodiment, the track2houses the permanent magnets and the movable elements3house the individually-excitable solenoids.

The movable elements3are arranged for carrying an object. In case the transporting apparatus is used in a machine, in particular a packaging machine, the above-mentioned object may be a device, or a tool, that carries out a certain operation in the machine.

In particular, in case of a packaging machine for manufacturing packages by folding, filling and sealing a web of packaging material, the device, or tool, can be a forming element for forming a package, or a moulding element for moulding plastics on the packaging material to obtain an opening device of the package.

The track2comprises a guiding member4on which the movable elements3are movable.

The guiding member4comprises a first plate5aprojecting from a first side60of a frame6of the track2.

The guiding member4also comprises a second plate5bprojecting from a second side61, opposite to the first side60, of the frame6.

The guiding member4has a first linear branch7and a second linear branch8. The first linear branch7and the second linear branch8are substantially parallel to each other.

In the embodiment shown the first linear branch7and the second linear branch8are arranged in a vertical plane.

The guiding member4further comprises a first curved branch9and a second curved branch (not shown) interposed between the first linear branch7and the second linear branch8. The first curved branch9and the second curved branch are opposite to each other. In this way, the guiding member4has a substantially oval longitudinal cross section.

The movable elements3comprise a supporting body14arranged for supporting the above-mentioned object, i.e. the device, or tool, in the case of a machine.

The movable elements3further comprise a first couple of rollers15, a further first couple of rollers16, a second couple of rollers17, a further second couple of rollers18, a third couple of rollers19and a further third couple of rollers20that are rotatably connected to the supporting body14and slidably coupled with the guiding member4.

The guiding member4comprises a first guiding surface11aand a further first guiding surface11bfacing towards the supporting body14, a second guiding surface12aand a further second guiding surface12bfacing away from the supporting body14, and a third guiding surface13aarranged transversally with respect to the first guiding surface11aand the second guiding surface12a, and a further third guiding surface13barranged transversally with respect to the further first guiding surface11band the further second guiding surface12b.

The first guiding surface11aand the further first guiding surface11bare mutually aligned.

The second guiding surface12aand the further second guiding surface12bare mutually aligned.

The second guiding surface12ais arranged on the opposite side of the supporting body14with respect to the first guiding surface11a.

The further second guiding surface12bis arranged on the opposite side of the supporting body14with respect to the further first guiding surface11b.

The first guiding surface11aand the further first guiding surface11bare parallel to the second guiding surface12aand the further second guiding surface12b.

The third guiding surface13ais perpendicular to the first guiding surface11aand to the second guiding surface12a.

The further third guiding surface13bis perpendicular to the further first guiding surface11band to the further second guiding surface12b.

The third guiding surface13ais parallel to the further third guiding surface13b.

The first plate5acomprises the first guiding surface11a, the second guiding surface12aand the third guiding surface13a.

The second plate5bcomprises the further first guiding surface11b, the further second guiding surface12band the further third guiding surface13b.

The first couple of rollers15slides along the first guiding surface11a.

The further first couple of rollers16slides along the further first guiding surface11b.

The second couple of rollers17slides along the second guiding surface12a.

The further second couple of rollers18slides along the further second guiding surface12b.

The third couple of rollers19slides along the third guiding surface13a.

The further third couple of rollers20slides along the further third guiding surface13b.

The first couple of rollers15comprises a first roller21and a second roller22.

The further first couple of rollers16comprises a third roller23and a fourth roller24.

The second couple of rollers17comprises a fifth roller25and a sixth roller26.

The further second couple of rollers18comprises a seventh roller27and an eighth roller28.

The third couple of rollers19comprises a ninth roller29and a tenth roller30.

The further third couple of rollers20comprises an eleventh roller31and a twelfth roller32.

The movable elements3slide on the track2along an advancing direction A.

The movable elements3move on the track2along an axis Z, parallel to the advancing direction A.

The first roller21, the second roller22, the third roller23, the fourth roller24, the fifth roller25, the sixth roller26, the seventh roller27and the eighth roller28prevents the movable element3from moving along a further axis Y perpendicular to axis Z and also perpendicular to the first guiding surface11a, the further first guiding surface11b, the second guiding surface12aand the further second guiding surface12b.

The ninth roller29, the tenth roller30, the eleventh roller31and the twelfth roller32prevent the movable element3from moving along a still further axis X perpendicular to axis Z and also perpendicular to the third guiding surface13aand the further third guiding surface13b.

Axis Z, further axis Y and still further axis X are perpendicular to each other.

Axis Z, further axis Y and still further axis X are to be intended as integral with the movable element3, as the movable element3moves along the track4.

The second roller22and the fifth roller25, and the fourth roller24and the seventh roller27, prevent the movable elements3from rotating around still further axis X, in a clockwise direction.

The first roller21and the sixth roller26, and the third roller23and the eighth roller28, prevent the movable elements3from rotating around still further axis X, in a counter-clockwise direction.

The tenth roller30and the eleventh roller31prevent the movable elements3from rotating around further axis Y, in a clockwise direction.

The ninth roller29and the twelfth roller32prevent the movable elements3from rotating around further axis Y, in a counter-clockwise direction.

The first roller21and the second roller22, and the seventh roller27and the eighth roller28, prevent the movable elements3from rotating around axis Z, in a clockwise direction.

The fifth roller25and the sixth roller26, and the third roller23and the fourth roller24, prevent the movable elements3from rotating around axis Z, in a counter-clockwise direction.

The rotation axes of the rollers of the first couple of rollers15, i.e. the rotation axes of the first roller21and the second roller22, are parallel to still further axis X and perpendicular to the third guiding surface13aand the further third guiding surface13b.

The rotation axes of the rollers of the further first couple of rollers16, i.e. the rotation axes of the third roller23and the fourth roller24, are parallel to still further axis X and perpendicular to the third guiding surface13aand the further first guiding surface13b.

The rotation axes of the rollers of the second couple of rollers17, i.e. the rotation axes of the fifth roller25and the sixth roller26, are parallel to still further axis X and perpendicular to the third guiding surface13aand the further third guiding surface13b.

The rotation axes of the rollers of the further second couple of rollers18, i.e. the rotation axes of the seventh roller27and the eighth roller28, are parallel to still further axis X and perpendicular to the third guiding surface13aand the further second guiding surface13b.

The rotation axes of the rollers of the third couple of rollers19, i.e. the rotation axes of the ninth roller29and the tenth roller30, are parallel to further axis Y and perpendicular to the first guiding surface11a, the further first guiding surface11b, the second guiding surface12aand the further second guiding surface12b.

The rotation axes of the rollers of the further third couple of rollers20, i.e. the rotation axes of the eleventh roller31and the twelfth roller32, are parallel to further axis Y and perpendicular to the first guiding surface11a, the further first guiding surface11b, the second guiding surface12aand the further second guiding surface12b.

The first roller21, the second roller22, the third roller23, the fourth roller24, the fifth roller25, the sixth roller26, the seventh roller27, the eighth roller28, the ninth roller29, the tenth roller30, the eleventh roller31and the twelfth roller32are mounted on the supporting body14by means of rotation units33, each supporting a group of rollers34.

Each group of rollers34comprises three rollers, a roller belonging to the first couple of rollers15or to the further first couple of rollers16, a further roller belonging to the second couple of rollers17or, respectively, to the further second couple of rollers18and a still further roller belonging to the third couple of rollers19or, respectively, to the further third couple of rollers20.

The supporting body14comprises a front part35substantially extending in a plane defined by axis Z and still further axis X and a first side part36aand a second side part36bprotruding from opposite sides of the front part35and each substantially extending in a plane defined by axis Z and further axis Y. The front part35is arranged to support the above-mentioned object.

Each rotation unit33comprises a rotation element37that is rotatably coupled to the supporting body14, in particular to the first side part36aor to the second side part36b, and is rotatable around a rotation axis parallel to the still further axis X, i.e. perpendicular to the third guiding surface13aand to the further third guiding surface13b.

Each movable element3comprises four rotation units33, in particular a first rotation unit33a(shown inFIG. 3) and a second rotation unit (not shown) rotatably coupled to the first side part36a, and a third rotation unit33c(shown inFIGS. 2 and 3) and a fourth rotation unit33d(shown inFIG. 2) rotatably coupled to the second side part36b.

The first rotation unit33acomprises the first roller21, the fifth roller25and the ninth roller29.

The second rotation unit comprises the second roller22, the sixth roller26and the tenth roller30. The third rotation unit33ccomprises the third roller23, the seventh roller27and the eleventh roller31.

The fourth rotation unit33dcomprises the fourth roller24, the eighth roller28and the twelfth roller32.

In the next passages of the description, since the first rotation unit33a, the second rotation unit, the third rotation unit33cand the fourth rotation unit33dare identical to each other, reference will be made to only one rotation element37, and the three rollers of the corresponding group of rollers34will be generally referred to—for sake of simplicity and conciseness—as roller41, further roller42and still further roller43.

It is to be intended that in the first rotation unit33aroller41corresponds to the fifth roller25, further roller42corresponds to the first roller21and still further roller43corresponds to ninth roller29.

Similarly, it is to be intended that in the second rotation unit roller41corresponds to the sixth roller26, further roller42corresponds to the second roller22and still further roller43corresponds to tenth roller30.

Similarly, it is to be intended that in the third rotation unit33croller41corresponds to the third roller23, further roller42corresponds to the seventh roller27and still further roller43corresponds to eleventh roller31.

Similarly, it is to be intended that in the fourth rotation unit33droller41corresponds to the fourth roller24, further roller42corresponds to the eighth roller28and still further roller43corresponds to twelfth roller32.

The rotation element37comprises a shaft portion38received in a hole39of the first side part36a, or the second side part36b. A bearing40is interposed between the shaft portion38and the first side part36a, or the second side part36b.

The rotation element37further comprises a bracket portion44that comprises a pin45that rotatably supports the roller41and a further pin46that rotatably supports the further roller42.

The rotation element37further comprises a seat47that receives the still further roller43.

The rotation element37comprises a still further pin48protruding into the seat47and rotatably supporting the still further roller43.

The axes of rotation of the roller41and the further roller42are aligned on a line L.

The axes of rotation of the roller41, the further roller42and the still further roller43are arranged in a plane P.

The minimum distance between the roller41and the further roller42is less than the width of the first plate5a, or the second plate5b, measured along further axis Y. In other words, the minimum distance between the roller41and the further roller42is less than the distance between the first guiding surface11aand the second guiding surface12aor, respectively, the further first guiding surface11band the further second guiding surface12b.

In this way, the roller41and the further roller42are mounted on the guiding member with interference, so as to avoid play, or clearance, between the movable elements3and the track2.

During operation, the movable elements3are moved on the track2independently from each other by individually controlling the corresponding solenoids.

The first roller21, the second roller22, the third roller23, the fourth roller24, the fifth roller25, the sixth roller26, the seventh roller27, the eighth roller28, the ninth roller29, the tenth roller30, the eleventh roller31and the twelfth roller32precisely guide the movable elements3in the advancing direction A, i.e. along axis Z and prevent any other movement of the movable elements3along still further axis X and further axis Y, and around still further axis X, further axis Y and axis Z.

Due to the rotation elements37, the line L is always kept perpendicular to the first guiding surface11aand the second guiding surface12aor, respectively, to the further first guiding surface11band the further second guiding surface12b. In particular, when the movable elements3move along the first curved branch9, or the second curved branch, the line L is always so oriented as to pass through the centre of curvature of the first curved branch9, or—respectively—the second curved branch.

Owing to the invention it is possible to obtain a transporting apparatus1in which the movable elements3are substantially not allowed any movement apart from the one along the advancing direction A.

In addition, due to the position of the first couple of rollers15, the further first couple of rollers16, the second couple of rollers17, the further second couple of rollers18, the third couple of rollers19and the further third couple of rollers20the transporting apparatus1has high stiffness, and the movable elements3may carry rather heavy objects without compromising a good positioning of the objects. In particular, in the case of a machine, the above-mentioned devices, or tools, can be precisely positioned also in case they are cantilevered to the movable elements3and, therefore, the movable elements3are subjected to significant loads.

In addition, due to the rotation elements37, the movable elements3are properly guided both along the first linear branch7and second linear branch8, and the first curved branch9and second curved branch.

Clearly, changes may be made to the transporting apparatus as described and illustrated herein without, however, departing from the scope of the present invention as defined in the accompanying claims.