Fitting for suction cup and suction cup

Push-on fitting (10) for a push-on suction cup (20) for a conveyor belt (30) for transporting or lifting goods, which push-on fitting (10) comprises a base disc (12) having a front side (11) and a rear side (13) and being adapted to be mounted in a hole (32) of the conveyor belt (30), said base disc (12) having a hole (15) for through airflow and being provided with a hollow push-on snap fitting pin (14) for through airflow, said pin (14) extending outwardly essentially perpendicular to the front side (11) and adapted to receive a push-on suction cup (20), wherein the snap fitting pin (14) comprises at least a pair of axial slots (16) adapted to provide at least a pair of flexible tongues (14a, 14b) formed in an end (17) of the pin (14) and in that the flexible tongues comprise a concentric snap fitting rim (18) having a variable diameter (D1), that can be varied by an end (19) part of the flexible tongues (14a, 14b) being acted upon, for receiving the push-on suction cup (20) provided with a washer (22) having a mounting hole (23) with a diameter (D2) smaller than a largest diameter (D1) of the rim (14c).

This application claims priority of European Application No. 14194332.4 filed Nov. 21, 2014, which is hereby incorporated herein by reference.

TECHNICAL HELD

The present invention is related to a fitting for a suction cup and a suction cup, in particular to a push-on fitting and push-on suction cup used in a conveyor belt for transporting and/or lifting goods.

BACKGROUND

Suction cups are used in vacuum transporting and/or lifting systems, wherein a plurality of suction-cups are provided on a conveyor belt or other transporting devices for lifting and/or transporting goods. Examples of technical fields employing vacuum transporting and/or lifting systems using conveyor belts or other devices provided with a plurality of suction-cups are industrial baking equipment. Particular applications of industrial baking equipment are so-called “depanners” for high volume production of bakery products, wherein a vacuum removal system having suction cups mounted on a conveyor belt are provided for lifting (“depanning”) bakery products from a pan. But, vacuum transporting and/lifting systems having suction-cups provided on a conveyor belt or other transporting devices for lifting and/or transporting goods are also known for other technical fields of application.

The suction cups can be mounted to the conveyor belt or to another suitable transporting device by means of suction cup fittings for holding the suction cups when assembled/mounted to the conveyor belt. Since the number of fittings and suction cups are typically (very) large, assembling/disassembling typically involves time-consuming work, say a whole day or even longer to shift cups. Typically, when servicing or repairing the suction cups, the suction cups are removed from the fittings by an operator or service personnel, typically manually. The fittings available can be of so-called “threaded” or “push-on” type. As regards the “threaded fittings”, the suction cups have to be screwed onto these when assembling (mounting) the suctions cups to the fittings.

A drawback with fittings of threaded type is time-consuming assembling/disassembling, in particular if the number of fittings and suction cups are (very) high since typically each suction cup has to be screwed or unscrewed manually and a large number of suction cups thus imply much manual labour in total.

Therefore, other types of fittings have found use such as fittings of “push-on” type, wherein the suction cups are mounted/assembled to the fittings by an operator or service personnel pushing the suction cups onto the fitting and dismounted/disassembled by pulling the suction cups off the fittings. A drawback is however, that also this procedure may be labour intensive and time-consuming if assembling/disassembling is cumbersome. Sometimes the suction cups are difficult to dismount/mount even for a skilled operator or service personnel. Another drawback is that suction cups may come loose during operation of the transporting/lifting system if the fittings and suction cups are not assembled properly or if the assembly is not resistant enough, for instance to forces acting on the suction cups assembled during operation of the transporting and/or lifting system. Thus, it is normally important that the suction cups are also properly mounted and that the fitting is able to hold the cups firmly and resistant enough to all types of forces acting thereon.

SUMMARY

It is the object of the invention to provide an improved push-on fitting for a suction cup and push-on suction cup of the above type, which do not require intensive labor during assembling/disassembling. This object is obtained by the solutions according to various aspects of the present invention as follows below.

According to a first aspect and an embodiment of the present invention, there is provided a push-on fitting for a push-on suction cup for a conveyor belt for transporting and/or lifting goods. The push-on fitting comprises a base disc having a front side and a rear side and is adapted to be mounted in a hole of the conveyor belt. The base disc has a hole for through airflow and is provided with a hollow push-on snap fitting pin for through airflow. The snap fitting pin extends outwardly essentially perpendicular to the front side of the base disc and is adapted to receive a push-on suction cup. The snap fitting pin comprises at least a pair of axial, axially in relation to an axis of the pin, slots adapted to provide at least a pair of flexible tongues formed in an end of the snap fitting pin. The flexible tongues comprise a concentric snap fitting rim having a variable diameter that can be varied by an end part of the flexible tongues being acted upon, for receiving the push-on suction cup provided with a push-on base part, such as washer, having a mounting hole with a diameter smaller than a largest diameter of the rim.

Herein, the term “conveyor belt” includes any type of transporting device that can be used instead of a conveyor belt providing the same technical functionality.

Herein, a definition of “push-on” fitting and suction cup is intended to mean that the suction cups are mounted/assembled to the fittings by pushing the suction cups onto the fitting and dismounted/disassembled by pulling the suction cups off the fittings.

Herein, the term “snap fitting rim” also includes the term “snap fitting edge” or any other snap fitting structure capable of holding the push-on suction cup during operation of the conveyor belt for transporting and/or lifting goods.

According to a second aspect and an embodiment of the present invention, there is provided a push-on suction cup for a push-on fitting according to the first aspect. The push-on suction cup comprises a push-on base part having a mounting washer provided with a hole having a diameter smaller than a largest diameter of the snap fitting rim.

The push-on fitting and suction cup according to the invention also permits simplified assembly and disassembly during service and maintenance. Typically, a tool designed for assembling/disassembling the suction-cups are provided such that the flexible tongues comprising a concentric snap fitting rim having a variable diameter can be varied by an end part of the flexible tongues being acted upon.

DETAILED DESCRIPTION OF EMBODIMENTS

Now is referred toFIG. 1, which schematically in cross-section shows a push-on fitting10for a push-on suction cup20and a push-on suction cup20mounted thereon according an embodiment of the present invention, respectively.

InFIG. 1, the push-on fitting10and push-on suction cup20is shown assembled/mounted together and mounted to a conveyor belt30in a ready-to-operate or operating mode. For simplicity, only one push-on fitting10, a push-on suction cup20and only a part of the conveyor belt30is shown and since other parts of the equipment for transporting or lifting goods, such as vacuum pipes etc. are of conventional type, they are well-known to the skilled person and therefore not further shown or described.

The push-on fitting10comprises a base disc11having a front12side and a rear13side and is adapted to be mounted in a hole32having a diameter D of the conveyor belt30. The base disc11has a hole15for through airflow (typically caused by a negative pressure in a medium such as air, in particular provided as vacuum), having a diameter Dairflow, as an example 9 mm, equal to the diameter of the hole32(not shown or mentioned explicitly since well-known for the skilled person) of the conveyor belt30minus a wall-thickness (not shown or mentioned explicitly since well-known for the skilled person) of the push-on fitting10, and is provided with a hollow push-on snap fitting pin14, of the same diameter Dairflowas the hole15in the base disc11, for through airflow (illustrated by an arrow “air”). The snap fitting pin14extends outwardly essentially perpendicular to the front side12and is adapted to receive a push-on suction cup20. The snap fitting pin14comprises at least a pair of axial, axially in relation to a longitudinal axis of the pin14, slots16adapted to provide at least a pair of flexible tongues14a,14bformed in an end part17of the snap fitting pin14. The flexible tongues14a,14b, flexible in a direction perpendicular to the longitudinal axis of the pin14, comprise a concentric (concentric to the pin14) snap fitting rim18having a variable (shown by a dashed line for a smaller diameter) diameter D1that can be varied by the end part17of the flexible tongues14a,14bbeing acted upon, for receiving the push-on suction cup20provided with a push-on base part22, and in particular a washer, in the following also referred to as “22”, also having a mounting hole23with a diameter D2smaller than a largest diameter (see solid line of D1) of the rim18when not acted on the end part17.

Herein, the expression “adapted to be mounted in a hole32of the conveyor belt30” as regards the push-on fitting means that the push-on fitting can be made as one entire piece intended to be able to mount only by using hand-force with or without a tool by pressing the push-on fitting10into the hole32. Alternatively, some type of screw-joint joining two pieces of the push-on fitting together, one from the front side of the conveyor belt30and one piece from the rear side of the conveyor belt, when mounting into the hole32of the conveyor belt30can be used instead.

The height of the push-on fitting10, and in particular the height of a part thereof inside a bilge part25is typically adapted such that products lifted by the bilge part are not harmed. This is however obvious for the skilled person to adapt and therefore not described in more detail.

According to an embodiment, a pair of axial slots16is formed inwardly (inwardly as seen from the end part17towards the base disc11) of the tongues14a,14b, so that these connect only through one respective bridge to a cylindrical base section (not shown explicitly) of the tongues14a,14b. Alternatively, two pairs, or even more, pairs of axial slots16can be provided, whereby the number of flexible tongues14a,14bcan be four or more. The push-on fitting10is typically made of the same material all through and can for instance be made of polyamide, but also other suitable polymer materials including other plastics can be used.

According to an embodiment, the base disc11can on the front side12be provided with a front flange12aadapted to prevent the base disc11from leaving the conveyor belt30at assembly of the push-on suction cup20.

According to an embodiment, the base disc11can on the rear side13be provided with a rear flange13badapted to prevent the base disc11from leaving the conveyor belt30at disassembly of the push-on suction cup20.

In the embodiment shown inFIGS. 1-3, the end part17has a rotationally symmetric shape comprising two semi-circular tongues14a,14bfacing each other to a cylindrical cross-sectional shape, but also other shapes such as square, or rectangular cross-sectional shape are also possible provided the tongues14a,14bare still flexible such that a cross-sectional area of the end part17and thereby the diameter of the rim18can be decreased when acted upon the end part17, typically by the mounting tool40, but not limited thereto.

The rim18can be semi-circular around the circumference of the pin18. Instead of a rim18other snap-on means such as an edge or the like can be provided instead for the rim18, provided the snap-fitting as described can be obtained. Thus, the term “rim” is to be understood as including at least the term “edge”.

Now is referred also toFIG. 2a, 2bshowing in two partially cross-sectional views, assembly of the suction cup for instance inFIG. 1. InFIG. 2ait is shown the how a push-on suction cup20, for instance the one shown inFIG. 1(but before assembly), comprising a push-on base part22having or being provided as a (mounting) washer (also referred to as reference numeral “22” in the following) provided with a hole23having a diameter D2smaller than a largest diameter D1, when the tongues14a,14bare not acted upon, of the rim18is held by a mounting tool40, which may be embodied as a hollow tube adapted to receive and hold (by friction) the push-on suction cup20. The washer22may be integrated with or separate (for mounting in the bilge part25before assembly) to a bilge part25of the push-on suction cup20. The bilge part25can be short or long and adapted to differing levels and different lifting movements.

The washer22can be made of at least two different materials having different flexibility, wherein an inner part22aof the washer22surrounding the hole23is more rigid than an outer part22bbeing more flexible. Additional reinforcement rings for increased stability, for instance made of polyimide, can be provided into the push-on suction cup20.

The suction cups are typically made of materials approved by the FDA (for instance according to FDA 21 CFR 177.2600) and the European Union, for instance according to EU directive 1935/2004. The suction cups can be transparent and with or without colour pigment, or any traceable material, but are often provided with traceable material such as magnetic material, typically if used in the food industry for instance.

FIG. 2ashows the push-on suction cup20held by the mounting tool40just before mounting/assembling to the push-on fitting10, andFIG. 2bduring mounting/assembling. The arrow shows a force F applied on the mounting tool40(by an operator, service personnel or the like) during mounting/assembling. The force is powerful enough to act on the end part17and press the flexible tongues14a,14btogether enough for the washer22to “jump over” an edge18aof the rim18. To be able to press properly on the end part17and be able to press the flexible tongues properly together to decrease the variable diameter D1of the rim18, the shape of an end part42of the mounting tool40adapted to press on the end part17of the flexible tongues14a,14btypically corresponds to the shape of the end part17, for instance they are both wedge shaped in the form of a truncated cone having larger diameter D1towards the base part11(seen from a direction corresponding to a mounting direction as illustrated by a line inFIG. 2a). At least, the mounting tool40has to be able to press the flexible tongues14a,14btogether to decrease the diameter D1of the end part17when acted upon by a pressing force F on a side part of14cthe truncated cone.

As shown inFIG. 2b, when the mounting tool40presses on the side part14c, and the diameter D1is decreased, finally the hole23of the washer22“jumps” over the edge18aof the rim18and snaps-on the pin14since the diameter D2of the hole23of the washer22is smaller than the diameter D1of the pin, when the pressure on the end part17is not applied anymore and also locks on due to a resilient force exerted by a bottom part26of the push-on suction-cup20, typically since the washer22is provided with elastic material pressing the washer22away from the front side12.

According to an embodiment, a distance d of the pin14between the front side12and a lower end (herein, the term “lower” means closer to the front side) of the rim14is adapted such that a mounted suction-cup20is locked by a resilient force (not shown explicitly) exerted by a resilient bottom part26(which may even be the push-on part22itself) of the suction-cup20within this distance d.

Now is referred toFIGS. 3aand 3bshowing in two partially cross-sectional views, assembly of the suction cup inFIG. 1.

To release the push-on suction cup20from the push-on fitting10, the mounting tool40is pressed against the push-on fitting10in the same way as during assembling (see above) until the hole23of the washer22jumps over the edge18aof the rim18and comes loose. Because of the resilient force action on the bottom part26of the push-on suction cup20, the push-on suction cup20will be pushed away from the push-on fitting10and comes loose such that the push-on suction cup20can be exchanged for instance. Because of friction force the push-on suction cup20will remain in the tool40during disassembly (as shown by the wording “friction” inFIG. 3b).

FIGS. 1-3show views of from above of the pin14, wherein it is shown that the flexible tongues14a,14bare rotationally symmetric bodies. While this design is the most preferred embodiment in aspects of production, maintenance and construction for different applications, the invention is in no way to be limited to flexible tongues having the shown design, as it is obvious to those skilled in the art that many of the advantages of the invention may also be implemented in tongues of other sectional shapes.

The invention has here been described with reference to specific embodiments only for illustrative purposes only. The claimed scope of protection is thus drafted to accommodate also such considered embodiments that are not specifically shown here but lie within the knowledge of those skilled in the art to practice with the guidance of the above description.