Compressible suction cup with additional vacuum compartment, and lip and bellows therefor

Abstract

To provide a suction cup which can be locked in at least a partial compressed state and has improved flexibility.SOLUTION: Disclosed is a suction cup for engaging and lifting an object comprising a lip, a bellows, and an upper portion, in a sealing state, connected to the bellows for connecting an inner volume of the suction cup to a source of vacuum, The suction cup, in an operative state, can be locked in at least a partly compressed state of the lip and / or the bellows. Locking is achieved by exhaust of air entrapped in a sealed exterior volume formed between the lip and the bellows and / or between one or more segments of the bellows in an operative state through one or more through open holes provided in the lip and / or the bellows when vacuum is connected to the suction cup.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a suction cup for attaching and lifting objects, the suction cup including a lip, a bellows, and an upper portion sealingly connected to the bellows for connecting the interior volume of the suction cup to a vacuum source, the cup being capable of being locked in an operative state with at least partial compression of the lip and / or bellows. Locking is achieved by evacuating air trapped in a sealed exterior volume formed between the lip and the bellows and / or between one or more segments of the bellows through one or more through-holes in the lip and / or bellows when a vacuum is connected to the suction cup in an operative state. The present invention also relates to a corresponding lip and corresponding bellows, each for use with the suction cup. [Background technology]

[0002] Suction cups are often used in automated industries to attach and lift various objects by using a vacuum within the suction cup. Suction cups are sometimes called vacuum pads. Conventionally used suction cups may also include bellows, for example to increase the compressibility and flexibility of the suction cup.

[0003] Many suction cups tend to lose their stability and frictional force when lifting an object at about one-third of their maximum load limit. Some cups, such as friction cups, rely heavily on being fully compressed to maximize their frictional force. Typically, a friction cup may include a hub rigidly connected to the upper mounting portion of the cup. If the friction cup's hub loses contact with the object, a major source of frictional force and stability is lost. Because the hub can be considered nearly rigid, if the top of the cup is displaced upward from its initial operating position relative to the object being lifted, the hub may lose contact with the object. In this state, the cup becomes less stable and the frictional force it generates is significantly reduced.

[0004] U.S. Pat. No. 4,600,229 discloses a vacuum cup with a convoluted bellows, which is said to have increased holding power without increasing the overall size or vacuum level of the cup compared to the prior art suction cup shown in Figures 1 and 2 of the specification. The suction cup disclosed in the specification has an annular volume that extends from the cup's main cavity over the bellows when in a collapsed operating state. The exterior surface adjacent the bellows convoluted has complementary ridges and grooves that interlock when the bellows is in a collapsed operating state. The cup may also include means for reducing slippage. However, in the collapsed operating state, the vacuum cup disclosed in U.S. Pat. No. 4,600,229 is fully compressed, as can be seen in Figure 4 of the specification, and is therefore very rigid. The vacuum cup disclosed in U.S. Pat. No. 4,600,229 also requires a workpiece stop (also known in the art as a hub) for its function. When a large force is exerted by the stop member on the face of the workpiece, marks or indentations may be caused by the hub.

[0005] In some applications, it may be desirable to be able to lock the suction cup in a fully or partially compressed state, while still being able to maintain a degree of flexibility of the suction cup in such locked, compressed state. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 4,600,229 Summary of the Invention [Problem to be solved by the invention]

[0007] It is an object of the present invention to provide a suction cup that can be locked in at least a partially compressed state and that provides improved flexibility in such a compressed state.

[0008] Preferably, the risk of marking the surface of the object by the suction cup should be avoidable. [Means for solving the problem]

[0009] In accordance with the present invention, a suction cup is provided with a bellows 30 including a lip 20 and at least one compressible bellows segment 37 including an upper outer surface 36 and a lower outer surface 35, the bellows 30 being sealingly connected to the lip, and an upper portion 5 sealingly connected to the bellows for connecting the interior volume 15 of the suction cup to a vacuum source, wherein the opposing upper outer surface 25 of the lip and the opposing lower outer surface 35 of the bellows, and / or the opposing lower outer surface 35 of an upper segment 37 of the bellows and the opposing upper outer surface 36 of an adjacent lower segment 37 of the bellows, are compressed relative to one another in a compressed state. With respect to the conventional suction cup 10 of the preamble of claim 1, the above object is achieved by the following salient features set forth in the characterizing part of claim 1, wherein the suction cup is characterized in that at least one through aperture 40 is provided in at least one of the opposing surfaces, the at least one through aperture 40 being in fluid communication with the internal volume of the suction cup, and a raised sealing portion 50 is provided in at least one of the opposing surfaces, the raised sealing portion being capable of forming a seal between the opposing surfaces in a compressed state of the suction cup.

[0010] Thus, in one aspect, the present invention relates to such a suction cup.

[0011] Depending on the positioning of the one or more through apertures and one or more raised sealing portions, one or more pairs of opposing surfaces (25; 35 and / or 36; 35) can be locked in compression. For any given pair of opposing surfaces, at least one through aperture is required to enable those surfaces to be locked in compression. Also, for any given pair of opposing surfaces, at least one raised sealing portion is required to enable those surfaces to be locked in compression.

[0012] In some embodiments, the lip is non-lockable relative to the bellows to allow the lip to maintain its flexibility in the activated state of the suction cup.

[0013] The present invention allows for delayed or slower relaxation of the Suction Cup from an actuated compressed state back to a relaxed, uncompressed state, thereby minimizing the potential risk of damaging the object 100 due to sudden expansion of the Suction Cup upon release of the object.

[0014] The suction cup of the present invention does not rely on the hub 60 for its locking function. Therefore, the suction cup of the present invention avoids the risk of marking or causing indentations on the surface of the object. In embodiments that do not include a hub, the force exerted by the suction cup on the surface of the object can be located in the outer region of the lip, which is less harsh on the surface of the object. This also minimizes the risk of ambient air leaking under the lip into the suction cup. Furthermore, the absence of a hub allows for better bonding of uneven surfaces, such as concave surfaces. In embodiments where a hub is not present and the lip does not exhibit a raised friction element 27 on its lower bonding surface 26, reduced loss of vacuum area due to leakage can be achieved.

[0015] However, in certain embodiments, the hub 60 is included to provide improved friction of the suction cup against the surface of the object 100 to which it is coupled.

[0016] Furthermore, in contrast to the cup disclosed in U.S. Patent No. 4,600,229, the cup of the present invention does not rely on an upper annular volume for its locking function. In a preferred embodiment, the upper portion 5 of the suction cup of the present invention may provide flexibility to the upper portion of the suction cup of the present invention.

[0017] The suction cup of the present invention can be made to allow a greater degree of displacement of the top, bellows, or lip, or any combination thereof, until the maximum lifting force of the cup is achieved in the activated state of the suction cup.

[0018] Also, because the upper annular volume and hub are not required according to the present invention, and because the mounting plate, if present, does not need to be as wide (as the upper annular volume such as that according to U.S. Pat. No. 4,600,229) the suction cup of the present invention can be made lighter and less complex than prior art suction cups.

[0019] In one embodiment of the suction cup of the present invention, the lip is removable from the bellows.

[0020] Accordingly, in another aspect, the present invention relates to a compressible lip 20 for an embodiment of the suction cup 10 of the present invention, the lip having an upper outer surface 25 and a lower bonding surface 26, the lip having a raised sealing portion 50 on the upper outer surface of the lip.

[0021] In a further aspect, the present invention relates to a compressible bellows 30 for an embodiment of the suction cup 10 of the present invention, the bellows comprising at least one bellows segment 37 including an upper outer surface 36 and a lower outer surface 35, at least one through aperture 40 provided in at least one of the surfaces, and a raised sealing portion 50 provided in at least one of the surfaces 35 and 36 of the bellows.

[0022] Further embodiments and advantages of the present invention will become apparent from the following detailed description and appended claims.

[0023] The term "top," as used herein, for example, with respect to the top exterior surface, is intended to refer to a location further away from the object 100 being coupled.

[0024] For example, the term "lower" as used herein with respect to the lower outer surface is intended to refer to a location closer to the object 100 being coupled.

[0025] The terms "segment" and "bellows segment" are used interchangeably herein to refer to a section of a bellows that includes an upper outer surface and a lower outer surface. A bellows may also include one or more segments. [Brief explanation of the drawings]

[0026] [Figure 1] 1 shows a conventional suction cup 10 including a top portion 5, a lip 20, and a bellows 30. FIG. [Figure 2] 1 shows an embodiment of a suction cup 10 of the present invention in a relaxed state. The bellows 30 of the embodiment shown includes only one segment 37. The embodiment shown includes two through apertures 40 and a raised sealing portion 50 formed in the lower outer surface 35 of the bellows 30. [Figure 3]3 shows the suction cup 10 of the present invention of FIG. 2 in an actuated compression state against an object 100 (in this case, a flat, dry steel plate), with the raised portion 50 forming a seal between the opposing surfaces 25 and 35, which seals the sealable compartment 45, which is in fluid communication with the internal volume 15 via the through aperture 40. [Figure 4] 1 shows an embodiment of a suction cup 10 of the present invention having a hub 60, the cup in an actuated compressed state. [Figure 5] 1 shows an embodiment of a suction cup 10 of the present invention in which the lip 20 is detachable from the bellows 30 by means of attachment means 70, 80 provided on the lip and bellows respectively, and both the lip and bellows exhibit apertures 40 therethrough. [Figure 6] 6 shows an embodiment of a lip 20 of the present invention corresponding to the lip of FIG. 5. The lip embodiment shown in FIG. 6 shows a raised friction element 27 on its lower mating surface 26. [Figure 7] 6 shows an embodiment of a bellows 30 of the invention corresponding to the bellows of FIG. 5, with the top portion 5 cut away from the bellows of FIG. 5. The bellows 30 of the embodiment shown includes only one segment 37. [Figure 8] 1 shows an embodiment of a suction cup 10 of the present invention having a bellows 30 including adjacent upper and lower compressible bellows segments 37. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0027] Depending on the positioning of the one or more through apertures 40 and the one or more raised sealing portions 50, one or more pairs of opposing upper and lower surfaces can be locked in compression. For any given pair of opposing upper and lower surfaces (25; 35, 36; 35), at least one through aperture is required to enable those surfaces to be locked in compression. Also, for any given pair of opposing upper and lower surfaces, at least one raised sealing portion is required to enable those surfaces to be locked in compression.

[0028] 3 between the opposing upper outer surface 25 of the lip 20 and the opposing lower outer surface 35 of the bellows 30 in the compressed state of the suction cup 10, and by providing the through aperture 40, the compartment can be evacuated through the through aperture 40 into the interior volume 15, and the suction cup can be locked in compression when connected to a vacuum. Embodiments of the suction cup of the present invention, such as those described above, in which the lip and the lower (or lowermost, if there is more than one segment) outer surface of the bellows can be locked in compression, provide improved maximum lifting force and improved contact of the lip, and also the hub, if present, with the object being coupled or lifted, thereby increasing friction between the suction cup and the object.

[0029] In embodiments such as that shown in FIG. 8, in which the bellows 30 includes at least an upper segment 37 and an adjacent lower segment 37, in the compressed state of the suction cup 10, a sealable compartment 45 (not shown) may be formed between the opposing upper outer surface 36 of the lower segment 37 and the opposing lower outer surface 35 of the upper segment 37, similar to the sealable compartment 45 formed between the lip and the bellows as shown in FIG. 3, thereby enabling the two adjacent segments of the bellows to be locked together in the compressed state.

[0030] The raised sealing portions 50 can be located on the opposing upper outer surface, the opposing lower outer surface, or both surfaces. For maximum stability, friction, and locking force, the raised sealing portions are preferably located on the outer edges of the surfaces, as shown in FIGS. 2-8. The cross-sectional geometry of the sealing portions 50 is not critical, so long as a tight seal can be formed with the opposing surface, or with an opposing mating raised sealing portion 50 on the opposing surface. For example, if the cross-section of the raised sealing portions 50 is essentially rectangular, an outer concentric raised portion 50 can be located on one opposing surface and mate with an inner concentric raised portion (not shown) on the other opposing surface. This allows for some movement within the sealing portions without breaking the seal or releasing the vacuum from the sealable compartment. Improved radial stability can also be achieved.

[0031] In embodiments in which the lip can be locked to the opposing lower surface of the bellows according to the present invention as described above, at least one through aperture 40 is provided in the upper outer surface of the lip, the lower outer surface of the bellows, or both. In a preferred embodiment, the at least one through aperture 40 of the present invention is provided in the lower outer surface of the bellows, because a reduction in the vacuum level would occur in the area surrounding the through aperture. Also, holes in the lip may be more easily blocked or contaminated, thereby impairing its normal and intended function. Furthermore, if the lip is subjected to wear, particularly when made relatively thin, providing holes in the lip may make the lip more vulnerable to cracking near the holes. For these reasons, holes in the lip are preferably avoided according to the present invention. However, in alternative, generally less preferred, embodiments, such as those intended to enhance ease of manufacture, at least one through aperture 40 is provided in the lip. In embodiments in which the lip exhibits through apertures 40, the apertures are preferably located between raised friction elements 27 or within recesses in the lower outer surface 26, as shown in FIG.

[0032] The through-openings 40 need to be small to avoid significant pressure loss within the cup in the event that the raised sealing portion 50 separates from the opposing surface, thereby causing vacuum to be lost from the sealable compartment and ambient air to enter the interior volume 15 through the through-openings 40. On the other hand, larger through-openings are believed to provide more effective venting of the sealable compartment upon actuation of the cup, reducing the risk of the sealing portion 50 separating from the opposing surface and therefore reducing the risk of vacuum being lost from the sealable compartment. Larger through-openings may also be advantageous when escaping ambient air needs to be vented from the compartment, such as when dust or the like is present on the sealing surface preventing a tight seal.

[0033] Typically, the cross-sectional area of ​​the small through aperture 40 is between 0.5 and 1 mm 2 It would be within the range.

[0034] The through aperture is always in fluid communication with the internal volume of the suction cup, such that a pressure difference across the aperture will create a flow of ambient air through the through aperture, such as when the suction cup is actuated. Therefore, means configured for opening and / or closing the aperture are not used according to the present invention.

[0035] In preferred embodiments including a lip that can be locked to a bellows, especially where a thin lip is desired, the raised sealing portion 50 of the present invention is provided on the bellows (and not on the lip).

[0036] As shown in Figure 3, raised sealing portion 50 also preferably prevents opposing exterior surfaces 25 and 35, which each form a sealable compartment 45, from contacting each other when the sealable compartment is evacuated. Similarly, raised sealing portion 50 also preferably prevents opposing exterior surfaces 35 and 36, such as those included in the embodiment shown in Figure 8, from contacting each other when the sealable compartment 45 formed therebetween is evacuated.

[0037] In a particular embodiment of the suction cup 10 of the present invention, the lip 20 is detachable from the bellows 30, as shown in FIG. 5. Means for making the lip and bellows detachable from one another, such as to simply allow the lip to be replaced, are known in the art and will not be described in detail herein. However, by way of example, such means are illustrated herein by means 70; 80, with attachment means 70 provided on the bellows and corresponding attachment means 80 provided on the lip, as shown in FIGS. 6 and 7, respectively. In such an embodiment, the present invention is believed to significantly reduce the uplift stress on the connection means between the lip and the bellows, i.e., on the attachment means 70, 80, with reference to the embodiment shown in FIG. 5, and therefore is believed to reduce the risk of undesired detachment of the lip from the bellows.

[0038] When the suction cup of the present invention returns to its relaxed state, ambient air flows through the through apertures, allowing the raised sealing portion 50 to separate from the opposing surface.

[0039] The suction cups of the present invention can be made of any material known in the art and conventionally used in compressible suction cups, preferably a flexible polymeric material. [Explanation of symbols]

[0040] 5 Top of suction cup 10 suction cups 15 Internal Volume 20 Lip 25 Upper outer surface of lip 26 Lower surface of lip 27 Raised friction elements 30 Bellows 35 Lower outer surface of bellows 36 Upper outer surface of bellows 37 Compressible Bellows Segments 40 Through hole 45 Sealable compartment, also known as additional vacuum compartment 50 Raised sealing area 60 Hub 70, 80 Mounting means 100 Objects to be joined by suction cups

Claims

1. 1. A suction cup for connecting and lifting an object, said suction cup comprising: Lip and a bellows including at least one compressible bellows segment including an upper outer surface and a lower outer surface, said bellows sealingly connected to said lip; an upper portion sealingly connected to the bellows for connecting the interior volume of the suction cup to a vacuum source; the opposing upper outer surfaces of the lip and the opposing lower outer surfaces of the bellows, and / or the opposing lower outer surfaces of the upper segment of the bellows and the opposing upper outer surfaces of the adjacent lower segment of the bellows, may be compressed relative to one another into a compressed state; the suction cup is characterized in that: at least one through aperture is provided in at least one of the opposing upper and lower outer surfaces, the at least one through aperture being in fluid communication with the interior volume of the suction cup; and a raised sealing portion is provided in at least one of the opposing upper and lower outer surfaces, the raised sealing portion being capable of forming a seal between the opposing surfaces in the compressed state of the suction cup to trap air between the opposing surfaces; and the through aperture is provided so that air trapped between the opposing surfaces can be evacuated through the through aperture.

2. The suction cup of claim 1 , wherein the lip and the bellows are detachable from one another.

3. The suction cup of claim 1 or 2, further comprising a hub.

4. 4. A suction cup according to claim 1, comprising at least a first bellows segment and an adjacent second bellows segment, wherein neither the opposing upper outer surface of the lip nor the opposing lower outer surface of the bellows has any through apertures.

5. 5. The suction cup of claim 4, wherein neither the opposing upper outer surface of the lip nor the opposing lower outer surface of the bellows has a raised sealing portion.

6. 4. A suction cup according to claim 1, wherein at least one through aperture is provided in the opposing upper outer surface of the lip and / or the opposing lower outer surface of the bellows, and wherein a raised sealing portion is provided on at least one of the opposing upper and lower outer surfaces, the raised sealing portion being capable of forming a seal between the opposing outer surfaces in the compressed state of the suction cup.

7. 7. The suction cup of claim 6, wherein the at least one through aperture is located in the opposing lower outer surfaces of the bellows and not in the lip.

8. 8. A suction cup according to claim 6 or 7, wherein the raised sealing portions are provided on the opposing lower outer surfaces of the bellows and not on the opposing upper outer surface of the lip.

9. The suction cup of claim 1 , wherein both surfaces of the pair of opposing outer lower and upper surfaces have a raised sealing portion.

10. 10. A suction cup according to any one of claims 1 to 9, wherein the lower outer surface of the lip comprises a friction element.

11. 3. A compressible bellows for use in a suction cup according to claim 2, comprising at least one bellows segment including upper and lower outer surfaces, at least one through aperture provided in at least one of the upper and lower outer surfaces, a raised sealing portion provided in at least one of the upper and lower outer surfaces of the bellows, the raised sealing portion capable of forming a seal between the opposing surfaces in the compressed state of the bellows segment to trap air between the opposing surfaces, and the through aperture provided to allow air trapped between the opposing surfaces to be vented through the through aperture.

12. 12. The compressible bellows of claim 11, comprising at least an upper bellows segment and an adjacent lower bellows segment, each including an upper outer surface and a lower outer surface, at least one of the opposing upper outer surface of the lower bellows segment and the opposing upper outer surface of the lower bellows segment having at least one aperture therethrough, and at least one of the opposing outer surfaces having a raised sealing portion.

13. 13. A compressible bellows according to claim 11 or 12, sealingly connected to an upper portion for use in the suction cup.

14. 3. A compressible lip for use in a suction cup according to claim 2, having an upper outer surface and a lower mating surface, the compressible lip having a raised sealing portion on the upper outer surface of the lip, the raised sealing portion being capable of forming a seal between the opposing surfaces in the compressed state of the bellows segments to trap air between the opposing surfaces, and the through aperture being provided to allow air trapped between the opposing surfaces to be vented through the through aperture.

15. 15. The compressible lip of claim 14, including at least one aperture therethrough connecting the upper outer surface of the lip with the lower mating surface of the lip.

16. 16. The compressible lip of claim 14 or 15, having raised friction elements on the lower mating surface of the lip.

Images