Partitioned compressible suction cup lip and suction cup including the lip

Abstract

The present invention relates to a zoned, compressible suction cup lip and a suction cup including such a lip. The present invention discloses a compressible lip for a suction cup having one or more zones in its engagement region, each zone including a flow channel capable of forming a restriction with the surface of an object to be engaged by the lip. The restriction thus formed limits the airflow from the zones, thereby allowing the suction cup provided with such a lip to maintain an overall high vacuum level despite pressure loss in one or more zones. The present invention also discloses a suction cup having such a compressible lip.

Description

Technical Field

[0001] The present invention generally relates to suction cups and, more particularly, to a compressible lip for a suction cup having one or more zones in its engagement region, wherein each zone is provided with a flow channel that, together with the surface of an object to be engaged by the lip, forms a restriction that restricts airflow out of the zone. The restriction formed by the lip with the surface of the object enables the suction cup provided with such a lip to maintain a high overall vacuum level even if pressure is lost in one or some of the one or more zones. The present invention also relates to a suction cup having such a lip. Background Art

[0002] Suction cups are commonly used in the automotive industry to join and lift various objects, such as packages, boxes, bags, steel sheets, flat glass, and automotive parts, by using reduced pressure in the suction cups. Suction cups may also be called vacuum suction cups. The objects to be joined and lifted typically vary in shape, size, material, and weight. Suction cups are typically used in lifting operations involving heavy objects. When positioned over a hole in the object to be lifted (such as a package, box, bag, a piece of steel sheet or flat glass, or an automotive part) through which ambient air can flow from the outside of the object, it may be possible for no vacuum to be formed in the suction cups, or for only an insufficient vacuum to be formed in the suction cups. Similarly, when placed over the edge of the object, i.e., so that a portion of the suction cup is outside the joining surface of the object, it is highly unlikely that a sufficient vacuum will be formed in the suction cups so positioned.

[0003] It is difficult to lift objects with holes or when the suction cup overlaps the edge of the object. In these cases, the high leakage flow makes it difficult to generate a sufficient vacuum level inside the suction cup, which often leads to pick failure.

[0004] US 9,682,485 B2 teaches a suction cup which, when engaged with an object to be processed, has a plurality of concentric sealing areas.

[0005] Double-lip flat suction cups are commercially available, for example, from Parker Pneumatic of Parker Hannifin Corporation under the trade name P5V-CFS Double Lip Flat Cup, which have dual concentric sealing lips that provide two seals for the vacuum. When the object being lifted bends, the outer lip seal may rupture, but the inner lip seal will maintain the vacuum, thereby continuing the lifting capability. Summary of the Invention

[0006] It would be desirable to provide a suction cup that can be placed over a hole in an object to be lifted, or over an edge of an object to be lifted, while allowing a sufficient vacuum to be created and maintained for both engagement and lifting capabilities.

[0007] According to the present invention, for a conventional compressible lip for a suction cup, wherein the lip has a central opening 50 to the vacuum at its upper portion and the lip extends outwardly to a sealing portion 35, which is located at the lower portion of the lip and defines an engagement area "A" of the lip for engaging the object 100 to be lifted, the above object is achieved by the following technical features of the present invention: the lip has a raised portion 60 extending along the partitions "a", "b", "c", "d", "e", "f", wherein the raised portion has a flow channel 70 to the vacuum from the central opening, and wherein the partitions are defined by the raised portion, or by a portion of the sealing portion and the raised portion, and wherein the flow channel is formed in the raised portion, wherein when the raised portion containing the flow channel comes into contact with the surface 105 of the object by compression of the lip, the flow channel is able to form a flow restriction 75 together with said surface of the object.

[0008] Thus, one aspect of the present invention relates to such a compressible lip 30 .

[0009] In another aspect, the present invention relates to a suction cup 10 having a compressible lip 30 of the present invention, the suction cup comprising: a hollow mounting portion 15 having upper and lower ends; a hollow body portion 25 having upper and lower ends; and a lip 30 having a central opening 50 to a vacuum at its upper portion, wherein the hollow body portion is sealingly connected to the lip at its lower end, the lip extending outwardly from the hollow body portion to a sealing portion 35 at the lower portion of the lip, the sealing portion defining an engagement area "A" of the suction cup for engaging and lifting an object, wherein the upper end of the hollow mounting portion is provided with an opening 20 adapted to be connected to a vacuum source, and The lower end of the hollow mounting portion is sealingly connected to the upper end of the hollow main body portion, and the suction cup has the following distinguishing technical features: the lip has a raised portion 60 extending along the partitions "a", "b", "c", "d", "e", and "f" of the joint area "A", and the raised portion has a flow channel 70 to the vacuum from the central opening, wherein the partition is defined by the raised portion, or by a portion of the sealing portion and the raised portion, and wherein the flow channel is formed in the raised portion, wherein when the raised portion containing the flow channel contacts the surface 105 of the object through compression of the lip, the flow channel is capable of forming a flow restriction 75 together with the surface of the object.

[0010] According to one embodiment of the present invention, the raised portion defines a partition "a", e.g. Figure 1When the raised portion containing the flow channel 70 contacts the surface 105 of the object 100 to be lifted, the flow channel and the surface 105 of the object 100 together form a restriction 75 through which the restricted airflow from the zone "a" is restricted.

[0011] According to another embodiment of the present invention, a portion of the sealing portion of the lip together with the raised portion defines a partition "a", for example Figure 2 As shown in .

[0012] In yet another embodiment, the inner raised portion 60a disposed on the inner portion of the lip and extending along the central opening of the lip has one flow channel 70 for each partition, e.g. Figure 3 As shown in .

[0013] In one embodiment, the radial raised portion 60b extends from the inner raised portion 60a to the sealing portion of the lip. In a preferred embodiment, six radial raised portions are provided, thereby providing six subareas "a", "b", "c", "d", "e", "f", for example, Figure 3 As shown in .

[0014] The compressible lip of the suction cup of the present invention has one or more zones. When the suction cup is actuated, as the lip is compressed toward the surface of the object to be joined, the raised portion 60 containing the flow channel 70 will come into contact with the surface. When the raised portion containing the flow channel comes into contact with the surface, the flow channel forms a restriction 75 with the surface. In addition to the flow channels leading to the zones, each zone is sealed against the surface of the object to be joined by means of a raised portion, or a combination of a portion of the sealing portion defining the zone and the raised portion, when the suction cup is actuated as described above. The airflow to each zone is restricted. Thus, only a certain limited amount of air can flow through each zone. If the suction cup of the present invention experiences high leakage in one of its zones, the restriction formed by the flow channel together with the lower surface of the object will restrict the airflow from that zone, allowing the remaining zones to maintain a high vacuum level.

[0015] Providing restricted flow zones makes the suction cup of the present invention a viable option for lifting porous or curved objects. Providing restricted flow zones also enables the picking up of objects placed haphazardly on conveyors where the suction cup lip might overlap the edge of the object. For such applications, it is preferred that the lip engagement area A be completely divided into zones.

[0016] According to the invention, the engagement area of ​​the lip is partially or completely divided into zones. The zones of the invention that can be restricted in flow upon actuation are also referred to as restricted zones.

[0017] Providing flow passages to each zone restricts the airflow from each zone when the suction cup engages an object, thereby allowing the suction cup to maintain an overall high vacuum level despite pressure losses in some zones of the suction cup.

[0018] The term "cup" as used in the context of a suction cup is not intended to limit the geometry of the engagement surface of the suction cup, but is intended to encompass engagement surfaces that may not only be circular, but also square, rectangular, oval, etc.

[0019] The term "flow channel" is used to refer to a channel that is effective to allow air to flow from a zone to a central opening connected to a vacuum source when the suction cup is actuated so that a raised portion containing the flow channel contacts a surface of an object, thereby enabling a reduced pressure in the zone to be achieved, and that is effective to restrict the flow of atmosphere from the partially exposed zone to the central opening of the suction cup when a vacuum is applied to the suction cup while a portion of the zone containing the channel is exposed to atmosphere.

[0020] The term "upper" (eg, as used herein in upper) is intended to refer to a location that is farther from the objects to be joined.

[0021] The term "lower" (eg, as used herein in lower) is intended to refer to a location that is closer to the objects to be joined.

[0022] The term "compressible" as used herein is intended to refer to the ability of the lip to move from a relaxed state of the lip wherein at most only the outer peripheral portion of the raised portion contacts the underlying surface of an object to be engaged by the lip, to a state collapsed against a surface wherein the raised portion of the lip is completely in contact with the surface.

[0023] As used herein, the term "zone" is intended to refer to a portion of the overall engagement area of ​​the lip that is defined by a raised portion, or by a combination of a portion of the sealing portion of the lip and the raised portion. A raised portion that defines a zone by itself or in conjunction with a portion of the sealing portion of the lip must be continuous, except for at least one flow channel provided in the raised portion.

[0024] Other embodiments and advantages of the invention will become apparent from the detailed description and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 An embodiment of a compressible lip 30 is shown having an engagement area "A" and a subarea "a."

[0026] Figure 2An embodiment of a compressible lip 30 is shown having an engagement area "A" and a partition "a," wherein the partition is defined by a portion of the sealing portion and the raised portion.

[0027] Figure 3 An embodiment of a compressible lip 30 is shown having a joining area "A" divided into six subareas "a," "b," "c," "d," "e," and "f."

[0028] Figure 4 An embodiment of a suction cup 10 is shown in an actuated state, wherein the suction cup 10 has Figure 3 lip 30 shown in FIG. The suction cup is shown placed on a transparent acrylic plate 100 so that two sections "b" and "c" are partially exposed to the atmosphere. As schematically shown for section "a," a restriction 75 is formed by the flow channel 70 together with the surface 105 of the object 100. A restriction 75 is also formed for each of the remaining sections "b," "c," "d," "e," and "f."

[0029] Figure 5 is a bottom view of a suction cup 10 having a lip 30 with a friction element 80. The various zones "a," "b," "c," "d," "e," and "f" are indicated by dashed lines, each zone being interrupted only by a flow channel 70, of which there is one in the illustrated embodiment.

[0030] Figure 6 Shown Figure 5 Cross-sectional view of the suction cup.

[0031] Figure 7 A conventional suction cup 10 is shown without the partitions of the present invention. DETAILED DESCRIPTION

[0032] The compressible lip and suction cup of the present invention have one or more flow restriction zones. Embodiments with only one flow restriction zone can be used, for example, where an obstruction (such as a hole) is at a known location on the object to be lifted, as long as the suction cup is oriented or aligned accordingly.

[0033] According to the invention, the partitions may be defined solely by raised portions extending along the partitions, or by a portion of the sealing portion and one or more raised portions. The raised portions may, for example, be in the form of ridges or walls.

[0034] Advantageously, the lip of the invention can be made in one piece.

[0035] When the suction cup of the present invention is actuated, each subzone is sealed from the surface of the object being joined, except for a flow restriction formed by the flow channel and the lower surface of the object, which is provided within each subzone. Each subzone is fluidly connected to the suction cup's central opening via the flow restriction, which in turn is connected to a vacuum source. Thus, in the suction cup's actuated operating state, the subzones are fluidly connected to the vacuum source only via the inventive flow restriction or restrictions.

[0036] When actuating a suction cup including a lip of the present invention, the suction cup can be considered to be evacuated in two steps. In the first step, when the lower sealing portion of the lip of the suction cup contacts the surface of the object to be joined, the sealing portion of the lip will seal against the surface of the object, and the main volume of the suction cup above the joining area will be rapidly evacuated through the central opening connected to the vacuum source. During the evacuation of the main volume, in the first step, one or more raised portions will contact the surface of the object to seal against the surface (in addition to one or more flow restrictions), and in the second step, one or more partitions will be evacuated to the central opening through the one or more flow restrictions in fluid communication with the central opening. Therefore, it can be considered that sufficient joining will be quickly established in the first step, and thereafter, complete evacuation of the one or more partitions will be established in the second step.

[0037] During the first step, the full capacity of the vacuum source (e.g., a pump) is connected to the entire engagement area of ​​the lip, allowing for rapid evacuation of the interior volume of the suction cup. Thus, during the first step, evacuation is performed without any flow restriction, which would otherwise hinder evacuation and result in excessively long response times. Thus, the present invention provides a short response time for the suction cup. In a preferred embodiment, the suction cup of the present invention includes a bellows.

[0038] According to the present invention, the restriction is only formed when the lip is completely collapsed against the surface of the object.

[0039] Preferably, the flow passage of the raised portion is positioned and arranged to face the center of the engagement area and at as short a distance as possible from the central opening of the lip.

[0040] The size and geometry of the zones and flow channels can vary, but are characterized by the ability to maintain varying vacuum levels as air flows through the suction cup, due to the zones being partially exposed to the atmosphere. For example, one exposed zone can maintain a pressure similar to atmospheric pressure, while another unexposed zone can simultaneously maintain a deeper vacuum. Therefore, in the event of atmospheric leakage into any individual zone or zones, the overall lifting force of the suction cup will not be reduced to the same degree as with conventional suction cups. In the event of atmospheric leakage into the prior art suction cup, a low, uniform pressure will prevail across the entire engaging surface of the suction cup, and the suction cup's lifting capacity will be severely reduced, or even completely lost.

[0041] Although the size of the flow channel that meets the above-mentioned objectives can vary, for example, depending on the size of the suction cup, the size of the associated partitions, the total number of partitions, and the total number of flow channels, the size of the flow channel will generally be between 0.2 and 4.0 mm. 2 range, more typically 0.4-1.5 mm 2 within the range.

[0042] The geometry of the flow channel is not critical, and the geometry may be, for example, square, rectangular, triangular, semicircular, and arcuate.

[0043] It is preferred that the wider dimension of the flow channel face the surface of the object to be joined. The more open the flow channel is at the lower portion of its surface facing the object, the longer it takes until a restriction forms, and the longer the full performance of the vacuum pump can be utilized before a restriction forms. For this reason, rectangular, triangular, semicircular, or arcuate flow channel shapes are generally preferred.

[0044] Therefore, while in principle a through hole (not shown) formed in the raised portion could alternatively be used as the flow passage and restriction, this alternative design would be considered inferior because it would not provide the advantages of the invention described above. Furthermore, the through hole would be more susceptible to clogging, contamination, and would also increase the complexity of manufacturing the lip.

[0045] In contrast to double-lipped flat suction cups known in the art, the claimed invention does not require a double lip. Furthermore, the exterior of the engagement area of ​​the claimed suction cup can be divided into one or more zones, thereby limiting the overall vacuum loss in the event of a loss in one or two zones.

[0046] In contrast to the suction cup disclosed in US 9,682,485 B2, which has only one sealing area, the claimed suction cup allows air to be sucked from the entire engagement area when the suction cup is actuated, thereby potentially regaining vacuum if vacuum is lost from one or more zones.

[0047] In order to enable the suction cup of the present invention to be placed arbitrarily in a position overlapping with the edge of the object to be lifted, it is preferred that the engagement area of ​​the suction cup should be completely divided into a plurality of zones, e.g. Figure 3 The one shown in is divided into 6 partitions.

[0048] The lip of the suction cup of the present invention may also have a raised contact element 80, for example, to improve stability, contact and / or friction. The height of such a contact element should not be as high as the height of the raised portion 60.

[0049] The cross-sectional area of ​​the flow channel, and therefore the cross-sectional area of ​​the flow restriction, can be designed to a variety of sizes to accommodate different applications. A smaller flow channel cross-section generally results in a smaller pressure drop across the suction cup. However, a smaller cross-sectional area may result in reduced performance when handling leaking objects (e.g., cardboard), which require a larger evacuation flow through the flow restriction.

[0050] Although in principle the present invention also allows for more than one flow channel 70 to be provided in a partition, a lower number is generally preferred, such as 1, 2 or 3 flow channels, in particular 1 or 2 flow channels. Most preferably, only one flow channel is provided for each partition, as it is generally believed that by using only one flow channel for each partition, the restriction can be more tightly adjusted.

[0051] The sealing portion 35 can be formed by a sealing convex portion extending along the periphery of the lip, or can be formed by the outer edge of the lip, or can be formed by thickening the material of the lip toward the outside of the lip. It is generally preferred that the sealing portion is a sealing convex portion. For example, the sealing convex portion can allow some compression or deformation, thereby providing better sealing ability, for example, over a small protrusion located on the lifting surface of an object. The sealing convex portion should preferably be narrow. However, for better wear resistance, it may be preferable to use an alternative embodiment instead of an external sealing convex portion.

[0052] The compressible lip of the present invention can be used with suction cups of any shape, size and material. In the relaxed state of the lip, the lip slopes from its central upper portion to its outer lower portion. In the relaxed state of the lip, the engaging surface of the lip is preferably substantially concave, for example, Figure 6 As shown in the . The lip of the present invention is flexible so that when it comes into contact with the surface of the object to be joined, it collapses against the surface of the object and empties through the central opening. By the collapse of the lip, the raised portion of the partition can come into contact with the surface of the object to be joined.

[0053] The lip may be made as a separate part, adapted to be attached to the hollow body and mounting portion, or to a bellows as disclosed in, for example, WO 2010 / 110719 A1 or EP 3 133 035 A1. Alternatively, the lip may be made integrally with the suction cup, or with a bellows for the suction cup.

[0054] Example

[0055] The present invention will be disclosed in more detail through the following examples.

[0056] In these examples, two polyurethane suction cups CUP1 and CUP2 with normal friction patterns are used. Figure 7The conventional suction cup shown in FIG, CUP2 is a suction cup according to a preferred embodiment of the present invention, which has Figure 3-Figure 6 The cross section of each of the six flow restriction sections is 1.287 mm. 2 , which is very large to allow rapid evacuation of the joint area. Each section of the lip is designed to allow a maximum flow rate of 12.75 Nl / min at a pressure differential of 60 kPa. The vacuum used during the test was 60 kPa.

[0057] Example 1

[0058] The test used an acrylic plate with three 6mm holes drilled in close proximity. When Cup 1 was placed over the three holes, it was found to withstand 14 kPa. When the suction cup of the present invention was placed over the three holes, so that all three holes were covered by the same partition, it was found to withstand 57 kPa. In contrast to Cup 1, when using Cup 2 of the present invention, increasing the number of holes covered by the same partition did not further reduce the pressure because the flow limit of that partition had already been reached.

[0059] Example 2

[0060] In this example, lift over the edge was tested. A plate similar to the acrylic plate used in Example 1 was used, except that it did not have any holes in it. When CUP1 was placed over the edge, it was found that CUP1 only withstood 7 kPa. CUP2 of the present invention was placed over the edge in the same manner as CUP1, which resulted in two of the six partitions being partially exposed to the atmosphere. CUP2 of the present invention was found to withstood 46 kPa, with two of the six partitions being partially exposed, as shown in FIG. Figure 4 In this example, an extension of the sealing portion corresponding to approximately one third of the total length of the sealing portion of the lip is positioned outside the objects to be joined.

[0061] During the test, measurements showed a maximum leakage flow of 14.1 Nl / min per partition.

[0062] Reference Signs List

[0063] 10 Suction cups

[0064] 15 Hollow mounting part

[0065] 20 openings for vacuum

[0066] 25 Hollow main part

[0067] 30 Compressible lip

[0068] 35 Sealing part

[0069] 50 Center opening for vacuum

[0070] 100 Objects to be joined or lifted

[0071] 105 Surface of object 100

[0072] A. Joint area

[0073] 60 raised part

[0074] 60a Internal raised portion

[0075] 60b radial protrusion

[0076] 70 flow channels

[0077] 75 Current limiting unit

[0078] af partition

[0079] 80 Raised contact elements

Claims

1. A compressible lip (30) for a suction cup (10) for engaging and lifting an object (100), wherein: The lip has a central opening (50) to the vacuum at its upper portion, the lip extending outwardly to a sealing portion (35) located at its lower portion, the sealing portion defining an engagement area (A) of the lip for engaging and lifting the object, It is characterized by: The lip has a raised portion (60) extending along a zone (a, b, c, d, e, f) of the engagement area (A), the raised portion having a flow channel (70) to the vacuum from the central opening, wherein the zone is defined by the raised portion or by a portion of the sealing portion and the raised portion, and wherein the flow channel is formed in the raised portion, wherein when the raised portion containing the flow channel contacts the surface (105) of the object by compression of the lip, the flow channel is capable of forming a restriction (75) with the surface of the object, The flow channel is configured to allow air to flow from the partition to the central opening connected to the vacuum source, so as to obtain a reduced pressure of the partition and to restrict the flow of atmospheric air from the partially exposed partition to the central opening of the suction cup.

2. The compressible lip according to claim 1, wherein The raised portion (60) includes an inner raised portion (60a) and two or more radial raised portions (60b) extending from the inner raised portion to the sealing portion, the inner raised portion, the two or more radial raised portions and the sealing portion together defining one or more partitions (a, b, c, d, e, f), wherein the inner raised portion of each partition is provided with a flow channel (70) to the vacuum from the central opening.

3. The compressible lip according to claim 2, wherein: The inner raised portion extends inside the lip along the central opening.

4. The compressible lip according to any one of claims 1 to 3, wherein The joining area of ​​the lip is circular.

5. The compressible lip according to any one of claims 1 to 4, wherein The engagement area of ​​the lip has one or more raised contact elements (80).

6. The compressible lip according to claim 5, wherein: The one or more raised contact elements form a friction pattern.

7. The compressible lip according to any one of claims 1 to 6, wherein Each of the one or more partitions has only one flow channel.

8. A compressible lip according to any one of claims 1 to 7, further comprising a bellows integrally formed with the lip.

9. A suction cup (10) for engaging and lifting an object (100), the suction cup comprising: a hollow mounting portion (15) having an upper end and a lower end; a hollow body portion (25) having an upper end and a lower end; and a compressible lip (30) having a central opening (50) to the vacuum at its upper part, wherein the hollow main body portion is sealingly connected to the lip at its lower end, the lip extending outwardly from the hollow main body portion to a sealing portion (35), the sealing portion being located below the lip, the sealing portion defining an engagement area (A) of the suction cup for engaging and lifting the object, wherein the upper end of the hollow mounting portion is provided with an opening (20) suitable for connection to a vacuum source, and the lower end of the hollow mounting portion is sealingly connected to the upper end of the hollow main body portion, It is characterized by: The lip has a raised portion (60) extending along a zone (a, b, c, d, e, f) of the joining area (A), the raised portion having a flow channel (70) to the vacuum from the central opening, wherein the zone is defined by the raised portion or by a portion of the sealing portion and the raised portion, and wherein the flow channel is formed in the raised portion, wherein when the raised portion containing the flow channel by compression of the lip comes into contact with the surface (105) of the object to be joined, the flow channel is capable of forming a restriction (75) together with the surface of the object, The flow channel is configured to allow air to flow from the partition to the central opening connected to the vacuum source, so as to obtain a reduced pressure in the partition and to restrict the flow of atmospheric air from the partially exposed partition to the central opening of the suction cup.

10. The suction cup according to claim 9, wherein: The hollow body portion includes a bellows.

11. The suction cup according to claim 9 or 10, wherein: The raised portion (60) includes an inner raised portion (60a) and two or more radial raised portions (60b) extending from the inner raised portion to the sealing portion, the inner raised portion, the two or more radial raised portions and the sealing portion together defining one or more partitions (a, b, c, d, e, f), wherein the inner raised portion of each partition is provided with a flow channel (70) to the vacuum from the central opening.

12. The suction cup according to claim 11, wherein The inner raised portion extends inside the lip along the central opening.

13. The suction cup according to any one of claims 9 to 12, wherein The engagement area of ​​the lip has a raised contact element (80).

14. The suction cup according to any one of claims 9 to 13, wherein The engagement area of ​​the lip of the suction cup is rounded.

15. The suction cup according to any one of claims 9 to 14, wherein Each of the one or more partitions has only one flow channel.

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