Suction cup having compact axial installation and release mechanism

A novel suction cup mounting apparatus having a novel compact axial suction cup installation and release mechanism and method for assembling such a suction cup apparatus. The suction cup device includes a suction cup portion of a plunger assembly fit within a concave drive base and coupled thereto by a rigid drive pin. An optional rotational drive member or “handle” structured to operate on an external surface of the drive base may be provided for manipulating the drive pin relative to the suction cup and drive base. The suction cup device is intended to secure some device—a “utilization device”—to a surface. Therefore, according to another aspect of the suction cup device, a utilization mounting surface is projected above the drive base.

FIELD OF THE INVENTION

The present invention relates to the field of suction cups, and in particular to axial suction cup installation and release devices and methods.

BACKGROUND OF THE INVENTION

Suction cups are generally well-known and commonly used to mount and secure objects to smooth surfaces such as the surfaces of glass, plastic, Formica, glazed tile, metal, and other smooth surfaces. A typical suction cup includes a cup body and a stem. The cup body is generally arcuate or circular and defines a concavity. Typically, the stem is integrally formed on the body and used as the place of attachment for the object to be supported by the suction cup. At least the body of the suction cup is made of rubber, plastic or other material having sufficiently elastically resilient properties such that, when the body is pressed against a smooth surface, the volume of concavity is reduced, thereby forcing air to be expelled so that the body forms an air-tight seal against the smooth surface. Atmospheric pressure outside the body retains the suction cup body against the surface. When the air-tight seal is broken, air rushes into the concavity, releasing the vacuum and the suction attachment to the surface. Whereupon the elastically resilient material of the suction cup body returns to its relaxed condition. The resilient suction cup can be repeatedly reused.

Suction cups are difficult to properly position. Once a suction cup is attached to a surface, the suction forces (atmospheric and friction) resist repositioning of the cup. Attachment of the suction cup to an object can also be a problem. Preferably, the attachment should be releasable.

Furthermore, the vacuum within the suction cup resists the resilient force of the body so that the force of suction balances the resilient force of the body of the suction cup. The result is a limit on the degree of vacuum which can be achieved.

One way this limitation on the vacuum can be at least partially overcome is by “pulling” the center of the suction cup body away from the surface, thereby at least partially overcoming the restraining effect of the vacuum and generating an even greater vacuum. The periphery of the suction cup forms an air-tight seal with the surface. When the center of the suction cup body is pulled resiliently away from the surface, a partial vacuum is formed between the body and the surface so that the suction cup body “sticks” to the surface. The greater the vacuum the better the cup sticks to the surface.

Several devices have been proposed to “pull” the center of the suction cup away from the surface in order to increase the suction. The most common arrangement, often found for example on the bases of pencil sharpeners and many kitchen appliances, involves a rod or crankshaft which extends mainly parallel to the surface to which the suction cup is to adhere. The center of the suction cup is attached to an eccentric section of the rod or crankshaft, and when a lever arm is turned, the center of the suction cup is pulled outward. U.S. Pat. No. 2,089,714, HOLDINGDEVICE, issued Aug. 10, 1937, to Schuler; U.S. Pat. No. 3,765,638, SUCTIONMOUNT, issued Oct. 16, 1973, to Harrison; and U.S. Pat. No. 4,934,641, CURVEDSURFACESUCTIONMOUNTINGAPPARATUS, issued Jun. 19, 1990, to McElhaney, all of which are incorporated herein by reference, all describe such shaft-based arrangements.

One problem with arrangements using crankshafts and eccentric rods is the lever arms which extend out from whatever device they are mounted in. The lever arms is all too easy to hit or snagged, and the suction is thereby accidentally released. Another drawback of lever arms is that the support and bearing structure for them is difficult to integrate into the structure of the device which is utilizing the suction cups. This complication increases costs and the likelihood of failure.

A further cause of increased costs associated with such suction cup assemblies according to the prior art is that they usually require suction cups that must be specially designed to accommodate the lever arms, crankshafts, and the like.

Holoff, et al., for example, discloses a suction cup assembly having a suction cup, a cam member, a cone member and a mating core member secured to the suction cup. The cone member has an outer periphery generally co-extensive with an outer portion of the suction cup, and a generally cylindrical inner opening closely enclosing a cylindrical outer surface of the core member. The cam member has generally cylindrical camming surfaces, and is mounted onto and closely engages either the core member or a camming flange on the cone member, depending on the embodiment. The cam member axially shifts the core member outward relative to the cone member by pulling the center of the suction cup away from a surface to which the suction cup may be adhered.

Belokin, et al. discloses a releasable suction cup formed by a cup body which has a duct passing therethrough and a valve element for opening the duct, whereby the vacuum holding the suction cup can be released for repositioning the suction cup. The valve extends through the duct and is threaded on one end to receive a threaded fastener which is used to move the valve element into a sealing position and to secure the suction cup to an object.

The axial suction cup devices of Holoff, et al. and Belokin, et al. and others however are overly complex to manufacture, assemble and operate, as well as suffering other limitations.

Therefore, the inventor of the present invention invented the apparatus and method for a suction cup device as disclosed herein inFIGS. 1-6, and in U.S. Pat. No. 6,666,420 issued on Dec. 23, 2003, which is incorporated herein by reference, having a compact axial suction cup installation and release mechanism. The suction cup device includes a suction cup within a concave housing, and an axial drive member structured to operate on an external surface of the housing. A drive shaft is coupled to a central portion of the suction cup and extends through an aperture in the housing, projecting above a drive surface axially aligned with the concave surface formed in the housing. The drive shaft extends through a central aperture in the axial drive member and interacts with an inclined drive surface to pull the central portion of the suction cup toward and push it away from the concave surface of the housing when the axial drive member is rotated in first and second opposite directions relative to the housing.

SUMMARY OF THE INVENTION

The present invention is a novel suction cup mounting apparatus having a novel compact axial suction cup installation and release mechanism and method for assembling such a suction cup apparatus. According to one aspect of the present suction cup, the suction cup device includes a suction cup portion of a plunger assembly fit within a concave drive base and coupled thereto by a rigid drive pin. An optional rotational drive member or “handle” structured to operate on an external surface of the drive base may be provided for manipulating the drive pin relative to the suction cup and drive base. The suction cup device is intended to secure some device—a “utilization device”—to a surface. Therefore, according to another aspect of the suction cup device, a utilization mounting surface is projected above the drive base.

The drive base includes a dish-shaped bell housing member formed with a shallow concavity in a first “suction” surface, and a drive stack member formed substantially upright on the bell housing member external of the concavity and substantially axially aligned therewith.

The plunger assembly includes the suction cup coupled to a foot portion of a substantially rigid drive shaft member. In the suction cup device, the drive shaft member extends through a central aperture in the drive base concavity that communicates with a chamber formed in the substantially upright drive stack member, and a deformable portion of the suction cup fits into the shallow concavity in the suction surface. The drive shaft member is slidable relative to the upright drive stack member along an operational drive axis of the device. A guide mechanism maintains relative rotational orientation between the drive shaft and drive stack members. A pair of cooperating installation drive and reaction surfaces and are formed between the drive shaft and the upright drive stack members. The cooperating installation drive and reaction surfaces are mutually inclined relative to the device operational drive axis. Together with the drive pin the cooperating mutually inclined installation drive and reaction surfaces form a spiral suction cup installation drive mechanism between the drive shaft and upright drive stack members. The cooperating installation drive and reaction surfaces are circumferential surfaces formed in respective tubular walls. By example and without limitation, relatively inclined circumferential slots in the respective tubular walls of the drive shaft and drive stack members form the cooperating circumferential installation drive and reaction surfaces. For example, a pair of the installation drive surfaces are formed as a pair of the circumferential slots diametrically opposed in the tubular walls of the upright drive stack and oriented substantially normal to the device operational drive axis. In other words, the circumferential slots are oriented substantially horizontal to the vertical tubular walls of the drive stack member. Alternatively, the pair of diametrically opposed circumferential slots forming the installation drive surfaces in the tubular walls of the drive stack member are optionally inclined relative to the device operational drive axis climbing in a clockwise spiral away from the dish-shaped bell housing member toward the utilization mounting surface projected there above.

A pair of the cooperating installation reaction surfaces are formed by example and without limitation as a pair of the circumferential slots diametrically opposed in the tubular walls of the plunger drive shaft member and angularly oriented relative to the device operational drive axis. In other words, the pair of diametrically opposed circumferential slots formed as spirals in the vertical tubular walls of the drive shaft member with the circumferential slots climbing in a counter-clockwise spiral away from the foot portion thereof and a central portion of the suction cup coupled thereto.

Else, when the pair of diametrically opposed circumferential drive slots forming the installation drive surfaces in the tubular walls of the drive stack member are inclined relative to the device operational drive axis for climbing in a clockwise spiral away from the dish-shaped bell housing member toward the utilization mounting surface, the pair of diametrically opposed circumferential slots forming the cooperating installation reaction surfaces are optionally oriented substantially normal to the device operational drive axis. In other words, the circumferential slots are optionally oriented substantially horizontal to the vertical tubular walls of the plunger drive shaft member when the drive slots forming the installation drive surfaces are inclined relative to the operational drive axis, whereby the spiral drive slots and uninclined circumferential reaction slots forming the cooperating installation reaction surfaces are cooperatively mutually inclined relative to one another and the device operational drive axis.

The drive pin interfaces with the cooperating installation drive surfaces and installation reaction surfaces for driving the drive shaft member of the plunger assembly along the operational drive axis inwardly of the chamber within the drive stack member of the drive base. In turn, the foot portion of the drive shaft member draws the central portion of the suction cup into the shallow concavity in the suction surface of the drive base. Meanwhile, a peripheral lip portion of the dish-shaped bell housing member around the mouth of the cavity is structured to cooperate with a thickened inner peripheral annular ring of the suction cup for constraining a larger peripheral lip of the suction cup from being drawn into the concavity. Thus, an integral thin deformably resilient annular portion of the suction cup is stretched between the relatively stiff round center section and the integral peripheral lip portion.

The drive pin and mutually inclined installation drive and reaction surfaces of the spiral suction cup installation drive mechanism thus cooperate to move the drive shaft member of the plunger assembly relative to the drive stack member of the drive base along the operational drive axis. This relative motion of the drive shaft and drive stack members result in moving the central portion of the suction cup into the shallow concavity, while the peripheral lip of the suction cup is constrained to remain substantially stationary relative to the peripheral lip portion around the mouth of the cavity so that the thin deformably resilient annular portion of the suction cup is stretched between the suction cup's center section and its integral peripheral lip portion.

When the cooperating installation drive surfaces and installation reaction surfaces are formed as the cooperating pairs of circumferential drive slots and reaction slots, respectively, a pair of diametrically opposed diamond-shaped keyhole openings results on opposite sides of the device where the pairs of mutually inclined cooperating drive and reaction slots intersect. The diametrically opposed pairs of mutually inclined cooperating drive and reaction slots formed through the opposing tubular drive stack and drive shaft side walls intersect substantially along a common axis of intersection which is oriented substantially normal to the device operational drive axis. The common axis of intersection is shared by the pair of diametrically opposed keyhole openings.

The drive pin is inserted through the diametrically opposed keyhole openings, and thereafter maintains the pair of keyhole openings. The inserted drive pin additionally operates to retain the plunger drive shaft member relative to the drive stack member of the drive base.

Circumferential rotation of the inserted drive pin relative to the drive shaft and drive stack members forces the diametrically opposed keyhole openings to move along the respective pairs of mutually inclined cooperating drive and reaction slots. As discussed herein, the guide mechanism maintains relative rotational orientation between the drive shaft and drive stack members. Therefore, the same circumferential rotation of the drive pin relative to the plunger drive shaft and drive stack members that forces the diametrically opposed keyhole openings to move along the respective pairs of mutually inclined cooperating drive and reaction slots simultaneously forces the plunger drive shaft member to move along the device operational drive axis relative to the stationary drive stack member of the drive base for stretching the thin deformably resilient annular portion of the suction cup between the suction cup's center section at the foot portion of the plunger drive shaft member and its integral peripheral lip portion that is constrained adjacent to the peripheral lip portion of the bell housing member around the mouth of the cavity.

According to another aspect of the present suction cup device, the drive pin is optionally manipulated directly for circumferential rotation relative to the plunger drive shaft member and the drive stack member of the drive base, or by means of the handle when present.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

In the Figures, like numerals indicate like elements.

The terms “up” and “down” and derivatives are used solely for clarity in describing the invention and relate to the relative orientation of the individual components shown in the Figures and the assembly relative to a surface to which it is attached.

FIG. 1is a pictorial view of the present invention embodied by example and without limitation as a suction cup device10having a novel compact axially-driven suction cup installation and release mechanism. Accordingly, as shown more clearly in subsequent Figures, a substantially “bell” shaped drive base12and a suction cup plunger assembly14are coupled to each other with a rigid drive pin16. The drive pin16also couples the drive base12and suction cup plunger assembly14to an optional rotational drive member or “handle”18, which optionally includes one or both of a manual operating means19and one or more directional indicators21.

The suction cup device10is intended to secure some device—a “utilization device”—to a surface. Therefore, a utilization mounting surface20is provided. By example and without limitation, the utilization mounting surface20is integrated with the drive base12which, in use, remains stationary relative to the suction cup plunger assembly14and an external mounting surface S. However, the utilization mounting surface20is optionally integrated with either the suction cup plunger assembly14or rotational drive member18without deviating from the scope and intent of the present invention. Alternatively, the utilization mounting surface20is a discrete unit separate from the other components but coupled thereto, also without deviating from the scope and intent of the present invention.

By example and without limitation, the utilization mounting surface20is structured as a sphere22of resiliently compressible material is presented on a substantially upright post24, as described by example and without limitation by the inventor of the present invention in U.S. Pat. No. 5,845,885, which is incorporated by reference herein in its entirety. As illustrated in one or more figures herein and described by example and without limitation in U.S. Pat. No. 5,845,885, the sphere22of resiliently compressible material is presented on the substantially upright post24for access by a pair of clamping arms26that together form a socket28that is positionally secured relative to the sphere22when a clamping mechanism30is tightened. By example and without limitation, as shown and described herein, a positionable mounting platform32is founded on a base34that includes a substantially upright post36presenting thereon another sphere38of resiliently compressible material.

The second sphere38of resiliently compressible material is captured in a second socket40formed at an opposite end of the clamping arms26and is relatively positionally secured by increased tightening of the clamping mechanism30. The positionable mounting platform32is optionally structured to support any of a variety of mobile devices or another device or structure of the user's choice. For example, a cradle for holding the mobile device or other device or structure is secured to a platform surface42with a quantity of screws or other fasteners through one or more mounting holes44.

Optionally, as by example and without limitation in U.S. Pat. No. 5,845,885 and illustrated here, one or both of the presentation posts24and36is narrowed or “necked down” to pass between recessed lip portions46and48of the clamping arms26forming the sockets28and40, as illustrated in one or more figures herein and described by example and without limitation in U.S. Pat. No. 5,845,885.

Alternatively, the utilization mounting surface20is structured as a pattern of one or more mounting holes raised above the operational features of the device. According to one embodiment of the invention, the utilization mounting surface20is formed external of the other components of the device10and spaced far enough therefrom to permit the compact axially-driven suction cup installation and release mechanism of the invention to fit their between.

FIG. 2is a partial cutaway view of the present suction cup device10configured in a deactivated state having a compact axially-driven spiral suction cup installation and release mechanism50configured in a released or “free” condition. Accordingly, the bell shaped drive base12, suction cup plunger assembly14and optional rotational drive member18, if present, are assembled substantially along an operational drive axis52with the drive pin16inserted substantially normal thereto.

The substantially “bell” shaped rigid drive base12is shown embodied by example and without limitation as a shallow dish-shaped bell housing54having a substantially wide and shallow concave recess or cavity56formed in a first “suction” surface58and a substantially upright drive stack60mounted external of the cavity56. The concave cavity56is by example and without limitation formed with a shallow semi-spherical shape that is further truncated at its inner surface by a substantially planar floor portion62. The concavity56is alternatively embodied as a shallow semi-spherical shape that maintains its curvature across the floor portion62. According to another alternative embodiment, the concavity56is embodied as a shallow “funnel” shape that either maintains its shape to the floor portion62, or is truncated at its inner surface by the substantially planar floor portion62. The drive stack60is formed as a relatively narrow section of substantially hollow tube that is substantially axially aligned with the concave cavity56and communicates freely therewith through an axial aperture64.

The utilization mounting surface20of the suction cup device10is provided by example and without limitation adjacent to one end of the drive stack60opposite from the cavity56. By example and without limitation, a portion of the substantially upright presentation post24substantially closes the end of the tubular drive stack60opposite from the aperture64and forms a floor66thereof and forming a substantially cylindrical interior chamber68therein. The presentation post24is necked down external of the cylindrical chamber68, and the sphere22of resiliently compressible material is presented on a necked down portion70thereof.

The suction cup plunger assembly14is formed around a substantially rigid tubular drive shaft72which is illustrated here by example and without limitation as being substantially tubular. Means are provided for coupling a suction cup74to one end of the tubular drive shaft72. By example and without limitation, an integral disk-shaped foot portion76expands outwardly from the end of the column-shaped body of the tubular drive shaft72. The circular foot portion76is provided with means78for adhering the moldable suction cup material thereto. For example, the adhering means78is embodied as a pattern of depressions in or holes through the foot portion76. Alternatively, short columnar projections or “pins,” mechanically roughened or chemically prepared surfaces, and other adhering means are also contemplated and may be substituted for adhering means78or used in different combinations without deviating from the scope and intent of the present invention.

The suction cup74is formed of a resiliently deformable material, such as silicone rubber, plastic or another elastically resilient material molded over the circular foot portion76of the drive shaft72. Thus, the adhering means78is optional and provided only to improve and ensure adhesion of the molded suction cup material to the drive shaft foot portion76. The suction cup74is provided with a resiliently deformable central suction portion80sized to be positioned within the concave cavity56of the drive base12and a larger peripheral lip portion82sized to extend outside of the cavity56and beyond the dish-shaped bell housing54.

The deformable suction portion80of the suction cup74includes a relatively stiff round center section84formed of the elastically resilient material over molding the foot76of the drive shaft72. The relatively stiff round center section84is surrounded by an integral thin deformably resilient annular portion86that extends to the integral peripheral lip portion82. Here, the annular portion86is illustrated in a relaxed or unstretched condition because the suction cup device10illustrated as being configured in a released or “free” state.

According to one embodiment of the invention, means are provided between the suction cup74and the dish-shaped bell housing54to constrain the peripheral lip portion82from being drawn into the concave cavity56of the drive base12when, during operation, the drive shaft72is withdrawn through the aperture64into the chamber68of the tubular drive stack60. By example and without limitation, the peripheral lip portion82of the suction cup74is formed with a thickened inner peripheral annular ring88of the elastically resilient material structured to cooperate with an annular groove90formed in a peripheral lip portion92of the dish-shaped bell housing54around the mouth of the cavity56adjacent to the first “suction” surface58. The annular groove90cooperates with the thickened inner peripheral annular ring88of the suction cup74for keeping the peripheral lip82from being drawn into the concavity56during installation of the suction cup device10.

Optionally, a tab94extends from the periphery of the peripheral lip portion82of the suction cup74. When the suction cup74is attached to a surface S, manual lifting of the tab94by the operator eases release of the suction cup device10.

Although less effective in operation than a rigid material, the drive shaft72is optionally molded of the plastic or other elastically resilient material from which the suction cup74is molded. Additionally, when molded of the same material as the suction cup74, the drive shaft72is optionally molded integrally with the suction cup74, and the foot portion76is eliminated.

The tubular drive shaft72portion of the suction cup plunger assembly14is sized to pass through the aperture64in the suction cup drive base12that communicates with the concave cavity56and into the cylindrical chamber68formed internally of the drive stack60. The tubular drive shaft72is expected to be generally cylindrical in cross-section and is sized to slidingly engage the aperture64and cylindrical chamber68of the drive stack60. However, other mating shapes for the plunger assembly's drive shaft72and the mating cylindrical chamber68are also contemplated and may be substituted without deviating from the scope and intent of the present invention.

The installation and release mechanism50is structured to operate effectively when the suction cup drive base12and tubular drive shaft72retain a substantially constant relative rotational orientation relative to the device operational drive axis52. Therefore, the tubular drive shaft72is shaped to cooperate with the drive stack60for maintaining such substantially constant relative rotational orientation about the device operational drive axis52, and thus remains rotationally oriented to the suction cup drive base12during operation. In the example shown, the drive stack60and mating drive shaft72are formed as substantially round tubes structured in a sliding fit so mutual revolution about the device operational drive axis52is possible. Accordingly, one or more guides96are formed between the tubular drive shaft72and the mating suction cup drive base12. For example, the guides96are provided as one or more slots or keyways98and a same number of mating slides or keys100that are formed between tubular drive shaft72and the mating suction cup drive base12. Here, by example and without limitation, a pair of the keyways98are recessed into opposite internal faces of tubular wall portion102forming the tubular drive stack60, and a pair of the mating keys100are formed on a substantially tubular wall portion104forming the drive shaft72. However, the relative locations of the keyways98and mating keys100are optionally reversed between the drive stack60and the drive shaft72without deviating from the scope and intent of the present invention.

Furthermore, the drive stack60and mating drive shaft72are alternatively formed as substantially square or rectangular tubes structured in a sliding fit only along the device operational drive axis52, whereby mutual revolution about the device operational drive axis52is impossible. Accordingly, the guides96are provided as mating corners and wall features between the wall portion104forming the drive shaft72and the internal faces of the wall portion102forming the tubular drive stack60.

The spiral suction cup installation drive mechanism50is also provided between the substantially upright drive stack60of the drive base12and the drive shaft72of the suction cup plunger assembly14. By example and without limitation, the spiral installation drive mechanism50is provided by the installation drive pin16in combination with cooperating relatively inclined circumferential installation drive and reaction surfaces106and108that are formed between the substantially upright drive stack60of the drive base12and the drive shaft72of the suction cup plunger assembly14. The circumferential installation drive and reaction surfaces106,108cooperate through the drive pin16to force the drive shaft72of the plunger assembly14to move along the device operational drive axis52through the aperture64into and through the cylindrical chamber68of the drive stack60, whereby the overmolded center section84of the suction cup74is pulled on the drive shaft foot portion76away from the mounting surface S to form a suction coupling therewith, as described herein.

As better illustrated by example and without limitation inFIG. 4, the installation drive surface106is formed circumferentially through the tubular outer wall portion102of the drive stack60portion of the drive base12, while the installation reaction surface108is formed circumferentially through the substantially tubular wall portion104forming the drive shaft72. By example and without limitation, the installation drive surface106includes a pair of installation drive surfaces106which is provided as a pair of substantially symmetrical circumferential keyways or slots110formed through opposite faces of the outer wall portion102of the drive stack60diametrically opposed across the axial aperture64. The circumferential drive slots110are sized to slidingly accept the drive pin16therethrough diametrically across the cylindrical chamber68of the drive stack60. When the installation drive surfaces106are formed by circumferential slots110, the drive slots110optionally also form a pair of circumferential release drive surfaces112opposite from the installation drive surfaces106. By example and without limitation, the circumferential drive slots110are formed substantially perpendicular of the device operational drive axis52, although as discussed herein, variations are also contemplated and may be substituted without deviating from the scope and intent of the present invention.

The cooperating circumferential installation reaction surface108are formed, by example and without limitation, as a pair of substantially symmetrical slots114formed circumferentially through opposite faces of the tubular wall portion104of the drive shaft72diametrically opposed across a substantially cylindrical chamber116formed therebetween. The circumferential reaction slots114are sized to slidingly accept the drive pin16therethrough diametrically across the cylindrical chamber116of the drive shaft72and are inclined relative to the device operational drive axis52and the keyways or slots110of the drive stack60. The circumferential reaction slots114thus form a pair of the installation reaction surfaces108as spiral slots formed in the tubular wall portion104of the drive shaft72ascending from nearer the foot portion76toward an opposite distal end118.

Optionally, the spiral installation drive mechanism50is also provided with anti-rotation “keeper” mechanism120. For example, the keeper mechanism120is provided when the spiral installation reaction surfaces108are extended at their minimum elevation relative to the foot portion76of the drive shaft72in a “shelf” that is oriented either substantially perpendicular to the device operational drive axis52or canted at a slightly negative inclination relative to the respective installation reaction surface108. The shelf-extension keeper mechanism120optionally forms a “saddle” as a shallow curve or “dish” shaped therein that cooperates with the drive pin16for providing the keeper mechanism120. Irrespective of configuration, the installation drive pin16rests on the shelf-extension120. When the shelf-extension120is negatively inclined or forms a saddle, as shown, it forms a detent between each installation reaction surface108and the respective shelf-extension120as an offset or a steeply negatively inclined plane (shown).

When the installation reaction surface108are formed by circumferential slots114, the circumferential reaction slots114optionally also form a pair of release reaction surfaces122opposite from the installation reaction surfaces108and positioned for cooperating with corresponding release drive surfaces112. The release drive and reaction surfaces112,122cooperate through the drive pin16to force the drive shaft72of the plunger assembly14to move along the device operational drive axis52in an opposite direction from the installation drive and reaction surfaces106,108through the aperture64and out of the cylindrical chamber68of the drive stack60, whereby the overmolded center section84of the suction cup74is permitted to follow the drive shaft foot portion76toward the mounting surface S to relieve the suction coupling therewith, as described herein. Thus, the spiral installation drive mechanism50also constitutes a spiral release drive mechanism.

By example and without limitation, the circumferential reaction slots114are inclined relative to the device operational drive axis52and the circumferential drive keyways or slots110of the drive stack60, whereby the installation reaction surface108are inclined relative to the corresponding cooperating installation drive surfaces106on same sides of the respective tubular wall portions102and104of the drive stack60and drive shaft72, and the opposing release reaction surfaces122are similarly inclined relative to the corresponding cooperating release drive surfaces112on same sides of the respective tubular wall portions102and104.

Alternatively, the inclined circumferential reaction slots114in the tubular wall portion104of the drive shaft72are instead formed substantially perpendicular of the device operational drive axis52, while the cooperating circumferential drive keyways or slots110of the drive stack60are inclined relative to the device operational drive axis52and the substantially perpendicular circumferential reaction slots114. However, optionally the circumferential reaction slots114in the tubular wall portion104of the drive shaft72and the cooperating circumferential drive slots110of the drive stack60are both inclined relative to the device operational drive axis52and each other without deviating from the scope and intent of the present invention.

Here, the drive pin16is illustrated as being positioned in the inclined circumferential reaction slots114adjacent to the end118of the drive shaft72distal from the foot portion76because the compact axially-driven spiral suction cup installation and release mechanism50of the present suction cup device10is configured here in the released or “free” state.

Optionally, a biasing mechanism124is positioned for urging the suction cup plunger assembly14away from a constrained relationship with the drive base12, which exists when the present suction cup device10is configured in an activated state having the compact axially-driven suction cup installation and release mechanism configured in an installed or “constrained” condition, as illustrated inFIG. 3. Accordingly, the biasing mechanism124is positioned for urging the suction cup74portion of the plunger assembly14generally out of the concavity56of the drive base12.

By example and without limitation, the biasing mechanism124is structured to urge the drive shaft72of the plunger assembly14to move along the device operational drive axis52through the aperture64and out of the cylindrical chamber68of the drive stack60, whereby the overmolded center section84of the suction cup74is permitted to follow the drive shaft foot portion76toward the mounting surface S to relieve the suction coupling therewith, as described herein. Thus, the biasing mechanism124aids the spiral installation and release mechanism50to relieve the suction coupling with the mounting surface S. Here, by example and without limitation, the biasing mechanism124is provided as a conventional compression spring positioned between the plunger assembly's drive shaft72and the drive stack60of the drive base12. For example, the spring or other biasing mechanism124is slidingly received into an optional second cylindrical chamber126formed in the presentation post24of the utilization mounting surface20that communicates with the chamber68of the tubular drive stack60along the device operational drive axis52through an aperture128in the floor66thereof. Else, the cylindrical chamber68is optionally extended within the drive stack60to provide space for the spring or other biasing mechanism124, if present.

The spring or other biasing mechanism124is selected to extend from an inner or floor portion130of the second cylindrical chamber126out through the aperture64and into of the cylindrical chamber68with sufficient length remaining before attaining its fully extended relaxed state to press against the end118of the drive shaft72with sufficient spring force the suction cup74of the plunger assembly14outward of the cavity56in the bell housing54of the drive base12.

When the end118of the drive shaft72is open into the cylindrical chamber116, as illustrated, an optional plate or disk132of substantially rigid material is optionally emplaced to constrain the spring or other biasing mechanism124between the end118of the drive shaft72and the inner or floor portion130of the cylindrical chamber126within the presentation post24. Else, the spring or other biasing mechanism124is sized to interface with the end118of the drive shaft72and fit within the space provided by an extended cylindrical chamber68. In either configuration, interference between the spring or other biasing mechanism124and the drive pin16is thus avoided.

The pressure of the spring or other biasing mechanism124tends to urge the drive shaft72of the plunger assembly14to slide outwardly of the cylindrical chamber68in the drive stack60. Such spring pressure thus loads the drive pin16in shear between the circumferential reaction slots114in the drive shaft72and the corresponding circumferential drive slots110of the drive stack60. The drive slots110and corresponding reaction slots114thus tend to grip the drive pin16in a scissors hold between the drive shaft72and the drive stack60. The resultant gripping action is normally sufficient to restrain the drive pin16from sliding or “walking” out of the drive slots110and corresponding reaction slots114.

In operation, the drive pin16is optionally rotated directly about the device operational drive axis52for operating the compact axially-driven spiral suction cup installation and release mechanism50of the present suction cup device10. As discussed herein, rotation of the drive pin16is about the device operational drive axis52causes the drive shaft72of the plunger assembly14to slide inwardly of the cylindrical chamber68in the drive stack60, whereby the overmolded center section84of the suction cup74drawn on the drive shaft foot portion76into the cavity56in the bell housing54of the drive base12for forming the suction coupling with the mounting surface S, as described herein.

However, the rotational drive member or “handle”18is optionally provided for convenience and appearance. The handle18is also structured to protect the drive pin16from jostling and inadvertent dislodgment from its position between the drive slots110and corresponding reaction slots114. By example and without limitation, the handle18includes at least a collar portion134formed with an inner tubular walled aperture136sized to slide over the outer wall portion102forming the tubular drive stack60of the bell shaped drive base12. The inner tubular wall136is sized sufficiently loosely to freely spin the collar portion134about the drive stack outer wall portion102. Furthermore, the collar134includes substantially symmetric diametrically opposed crosswise apertures138piercing the inner tubular wall136along a diameter thereof. The crosswise apertures138are sized to slidingly receive the drive pin16therethrough, although one or both apertures138may be slightly undersized to grip the drive pin16and constrain it from backing out during repeated operations of the suction cup device10. One or both of the apertures138is optionally formed with a countersink or counter-bore (shown) to receive a head portion140of the drive pin16into the collar134.

Optionally, the handle18includes a skirt portion142extended from the collar portion134and flowing over but detached from the shallow dish-shaped bell housing54of the drive base12. When present, the skirt portion142includes an annular hem portion144opposite from the collar portion134and having a substantially planar lip146structured to follow the peripheral lip portion92of the dish-shaped bell housing54around the mouth of the cavity56. As best illustrated by example and without limitation inFIG. 1, when present, the manual operating means19is optionally provided on either the collar portion134or skirt portion142for easier manipulation by the user. By example and without limitation, the manual operating means19(FIG. 1) is provided as a pattern of finger grips formed in the collar134or skirt portion142for ease in rotating the handle18and with it the drive pin16. By example and without limitation, the finger grip operating means19are formed as finger-tip sized indentations recessed into the skirt portion142adjacent to its hem144. The manual operating means19alternatively take other convenient and ornamental shapes than the finger grips and may be substituted without deviating from the scope and intent of the present invention.

When present, the one or more directional indicators21(FIG. 1) are also provided on the collar134or skirt portion142for indicating device installation and release directions of rotation of the handle18. By example and without limitation, a pair of the directional indicators21are illustrated here as pictographic directional indicators having arrow shapes recessed into opposite sides of the skirt portion142adjacent to the finger grip operating means19. Alternatively, the directional indicators21are textual directions, such as “ON” and “OFF,” without deviating from the scope and intent of the present invention. Optionally, both pictographic and textual directional indicators21may be provided, for example, with the textual directional indicators21adjacent to the pictographic directional indicators21, as illustrated by example and without limitation by the inventor of the present invention in U.S. Pat. No. 6,666,420, which is incorporated herein by reference. Accordingly, during operation clockwise or counter-clockwise forces are exerted by the user's fingertips in the finger grips19for rotating the rotational drive member or “handle”18about the device operational drive axis52in the directions indicated by the pictographic and/or textual directional indicators21. The drive pin16is responsively rotated relative to the cooperating slots110and114of the respective drive stack60and drive shaft72for moving the drive shaft72relative to the drive stack60along the operational drive axis52, as disclosed herein.

FIG. 3is a partial cutaway view of the present suction cup device10configured in an activated state having the compact axially-driven suction cup installation and release mechanism configured in an installed or “constrained” condition. Accordingly, the bell shaped drive base12, suction cup plunger assembly14and rotational drive member or “handle”18are assembled substantially along the operational drive axis52with the drive pin16inserted substantially normal thereto. The drive pin16is inserted through the cooperating slots110and114of the drive stack60and drive shaft72, respectively, adjacent to the respective installation drive and reaction surfaces106and108. When the handle18is present, the drive pin16is simultaneously inserted through the cooperating crosswise apertures138of its collar portion134.

In operation, the handle18is rotated to rotate the drive pin16about the device operational drive axis52into a position within the inclined circumferential reaction slots114(or drive slots110) spaced a maximum distance from the foot portion76of the drive shaft72and the suction cup74. The drive shaft72and drive stack60are constrained against relative revolution about the device operational drive axis52by the guides96. Therefore, as illustrated inFIG. 2, this extreme positioning of the drive pin16relative to the inclined reaction slots114(or drive slots110) causes the drive shaft72of the plunger assembly14to slide along the device operational drive axis52outwardly of the cylindrical chamber68in the drive stack60to a maximum degree. This extreme motion of the drive shaft72relative to the drive stack60causes the drive shaft's foot portion76to move outwardly of the cavity56in the suction surface58of the drive base bell housing54. Substantially all tension in the suction cup74is thereby relieved. However, the annular groove90in the peripheral lip portion92of the dish-shaped bell housing54around the mouth of the cavity56cooperates with the thickened inner peripheral annular ring88of the suction cup74for maintaining substantial concentricity of the suction cup74relative to the bell housing54of the drive base12. Pressure of the spring or other biasing mechanism124effectively restrains the drive pin16from sliding or “walking” out of the cooperating circumferential drive and reaction slots110and114.

With the rotational drive member or “handle”18thus rotated to relieve pressure between the installation drive pin16and the cooperating relatively inclined drive and reaction slots110and114, the peripheral lip portion82of the relaxed suction cup74is placed against the mounting surface S to which is to be attached. When the operator is satisfied with the position of the suction cup device10relative to the attachment surface S, a torque load is applied via the finger grips19of the rotational drive member or “handle”18to rotate the drive pin16about the device operational drive axis52in an “ON” direction, which is optionally indicated by the pictographic and/or textual directional indicators21. The drive pin16is thus rotated relative to the cooperating circumferential drive and reaction slots110and114against the respective circumferential installation drive and reaction surfaces106and108.

During rotation, the installation drive pin16interfaces with the horizontal or downwardly ramping axial installation drive surfaces106in the tubular drive stack60of the suction cup drive base12and the upwardly ramping axial installation reaction surface108in the drive shaft72of the suction cup plunger assembly14. Continued application of the torque load to the rotational drive member18causes the installation drive pin16to travel circumferentially along both the installation drive surfaces106and the relatively inclined installation reaction surfaces108. The relative inclination between the installation drive and reaction surfaces106and108forces the drive shaft72to move along the device operational drive axis52relative to the drive stack60when the drive pin16is moved. In other words, as the drive pin16travels circumferentially along the installation drive surfaces106, the relatively inclined installation reaction surfaces108are simultaneously ramped downwardly over the drive pin16toward the foot portion of the drive shaft72. However, the drive shaft72of the suction cup plunger assembly14is constrained by the guides96, i.e., mating keyways98and keys100or other structural features, to move relative to the tubular drive stack60of the suction cup drive base12only along the device operational drive axis52without relative rotation. Therefore, circumferential motion of the drive pin16along the relatively inclined installation reaction surfaces108simultaneously forces the drive shaft72axially upwardly along the device operational drive axis52into the cylindrical chamber68of the drive stack60. The foot portion76is carried upwardly along the device operational drive axis52as part of the drive shaft72. The center section84of the suction cup74to his drawn upwardly with the foot portion76into the concavity56and away from the external attachment surface S. Meanwhile, the peripheral housing lip92manually maintains shape and position of the suction cup peripheral lip82external to the concavity56. In effect, circumferential motion of the drive pin16along the relatively inclined installation drive and reaction surfaces106and108pulls the drive shaft72of the plunger assembly14along the device operational drive axis52through the axial aperture64into the cylindrical chamber68of the drive stack60. The same circumferential motion of the drive pin16along the relatively inclined installation drive and reaction surfaces106and108simultaneously pulls the drive shaft's foot portion76through the concavity56away from the suction surface58of the drive base bell housing54. The overmolded center section84of the suction cup74is simultaneously pulled on the drive shaft foot portion76away from the mounting surface S to initiate formation of a suction coupling therewith.

As insertion of the plunger assembly's drive shaft72within the drive stack's interior chamber68increases, the portion within the concavity56shortens. The thin deformably resilient annular portion86of the suction cup74is forced to stretch between the withdrawing center section84and the positionally fixed peripheral lip82. Meanwhile, interaction with the annular groove90of the drive base housing's lip92operates to seal the peripheral lip82of the suction cup74flush against the attachment surface S, whereby an airtight cavity148is formed between the suction cup74and the attachment surface S wherein a partial vacuum is formed relative to ambient atmospheric pressure.

As discussed herein, means are provided between the suction cup74and the dish-shaped bell housing54of the drive base12for constraining the peripheral lip portion82from being drawn into the concave cavity56of the suction surface58when, during operation, the plunger drive shaft72is withdrawn through the aperture64into the chamber68of the tubular drive stack60. By example and without limitation, the peripheral lip portion82of the suction cup74is formed as an annular ring of the elastically resilient material structured to cooperate with the annular groove90formed in the peripheral lip portion92surrounding the mouth of the cavity56adjacent to the suction surface58for keeping the peripheral lip82from being drawn into the concavity56during installation of the suction cup device10. Accordingly, the lip portion82of the suction cup74includes the thickened inner peripheral annular ring88that forms an annular “shelf”150structured to fit within the annular groove90between respective substantially concentric outwardly and downwardly projections152,154. The integral peripheral lip82may extend outwardly in a thickened concentric outer annular ring portion156having a cross-section of sufficient thickness to avoid curling during installation of the suction cup device10, thereby effectively increasing the suction cup footprint and the holding power of the suction cup device. In operation, the annular groove90captures the thick peripheral annular ring88portion of the suction cup lip82. The downward projecting portion154of the housing lip92keeps the suction cup lip82from being drawn into the concavity56during installation of the suction cup device10, while the outwardly projecting portion152helps to keep the suction cup lip82from curling.

Rotation of the axially-driven rotational drive member18ceases when the drive pin16encounters the ends of one or both of the circumferential drive and reaction slots110and114. Other rotational stops may be provided when the installation drive and reaction surfaces106and108are not provided as respective drive and reaction slots110and114.

The drive pin16is constrained in this position relative to the circumferential drive and reaction slots110and114by the anti-rotation keeper mechanism120, whereby the drive pin16is settled on the saddle behind the detent81, as shown, at minimum spacing from the foot portion76of the drive shaft72, which ensures maximum elevation of the center section84of the suction cup74relative to the suction surface58of the drive base bell housing54. Passing the drive pin16over the optional detent81, as well as the tension generated in the stretched annular portion86of the suction cup74, ensures that the drive pin16cannot back down the inclined reaction drive surfaces108.

Simultaneously withdrawal of the plunger assembly's drive shaft72into the drive stack's interior chamber68, the spring or other biasing mechanism124is compressed along the device operational drive axis52within the cylindrical chamber126of the presentation post24between the floor portion130thereof and the end118of the drive shaft72. As disclosed herein, when the end118of the drive shaft72is open into the cylindrical chamber116, as illustrated, the plate or disk132is optionally emplaced to constrain the spring or other biasing mechanism124between the end118of the drive shaft72and the inner or floor portion130of the cylindrical chamber126to avoid interference with the drive pin16.

The suction cup device10is released from the attachment surface by release of the relative vacuum within the suction cup74. This is accomplished by collapsing the airtight cavity148by driving the center84of the suction cup74downwardly to the attachment surface, whereby tension in the stretched deformably resilient annular portion86is released and the suction cup74returns to its relaxed condition. The center84of the suction cup74is driven downwardly by interaction of the drive pin16with the cooperating release drive and reaction surfaces112and122when the torque load is applied to rotate the drive member18in a release direction, as indicated by the optional directional indicators21, when present. For example, a released torque load is applied to the optional finger grip or other operating means19, when present, of the rotational drive member or “handle”18. Force by the drive pin16moving upwardly along the cooperating release drive and reaction surfaces112and122combines with the elasticity of the stretched deformably resilient annular portion86material of the suction cup74to push the plunger drive shaft72down along the device operational drive axis52through the axial aperture64into the concavity56. When the upward force on the plunger drive shaft72is completely removed so that the suction cup74is relaxed, the relative vacuum in airtight cavity148holding the suction cup device10against the attachment surface S is released. Thereafter, the device10can be moved by lifting the tab94, which breaks the airtight seal between the suction cup's peripheral lip82and the attachment surface S.

FIG. 4is an exploded cross-sectional view that illustrates assembly of the novel suction cup device10. If present, the optional rotational drive member or “handle”18is fit over the bell shaped drive base12along the device operational drive axis52.

If present, the optional spring or other biasing mechanism124is fit into either the second cylindrical chamber126within the presentation post24, or the extended length of the cylindrical chamber68of the drive stack60. If the optional spring or other biasing mechanism124is present and smaller than the end118of the drive shaft72, the optional plate or disk132of substantially rigid material is fit between the biasing mechanism124and the drive shaft end118before the drive shaft72is inserted through the aperture64and into the cylindrical chamber68of the drive stack60with the end118thereof facing toward the floor66thereof. Else, if the optional spring or other biasing mechanism124is present and is sized to interface with the end118of the drive shaft72, the drive shaft72is optionally inserted through the aperture64and into the cylindrical chamber68of the drive stack60with the end118thereof directly interfacing with the biasing mechanism124.

The guides96between tubular drive shaft72and the mating tubular drive stack60of the suction cup drive base12are aligned with the one or more slides or keys100mating with corresponding slots or keyways98. The drive shaft72is pushed into the cylindrical chamber68of the drive stack60. If present, the biasing mechanism124is simultaneously compressed within the cylindrical chamber126of the presentation post24, or within the extended cylindrical chamber68of the drive stack60. Inserting the drive shaft72is pushed into the cylindrical chamber68of the drive stack60substantially automatically centers the peripheral annular ring88of the suction cup74relative to the cooperating annular groove90surrounding the mouth of the cavity56adjacent to the first suction surface58. As the peripheral annular ring88of the suction cup74approaches the first suction surface58of the drive base12, the downward projecting portion154of the housing lip92fits inside the annular shelf portion150, while the outwardly projecting portion152interfaces with its top surface. The larger peripheral lip portion82of the suction cup74extends outside of the cavity56and beyond the dish-shaped bell housing54.

The guides96between tubular drive shaft72and the mating tubular drive stack60of the suction cup drive base12cause the cooperating drive and reaction slots110and114to be aligned along the device operational drive axis52. Pressure (indicated by arrow158) is applied, as to the center portion84of the suction cup74, to hold the assembled plunger assembly14together with the drive base12. The drive pin16is pushed through a first of the crosswise apertures138in the collar134of the handle18. Two methods are recognized for installing the drive pin16. According to one method, the pressure (indicated by arrow158) is applied to plunger assembly14along the device operational drive axis52until the cooperating circumferential drive and reaction slots110and114intersect along an axis (indicated by arrow160) oriented substantially normal to the device operational drive axis52. The handle18is rotated on the drive base12about the device operational drive axis52until the drive pin16encounters the axis of intersection (indicated by arrow160) between the cooperating circumferential drive and reaction slots110and114, whereupon the drive pin16is pushed through a keyhole opening162(e.g.,FIGS. 2,3) that results between the respective side walls102and104of the tubular drive stack60and drive shaft72along the axis of intersection (indicated by arrow160) of the cooperating drive and reaction slots110and114. The drive pin16is passed through the chamber116within the drive shaft72and through another keyhole opening164(e.g.,FIG. 2) in the respective side walls102and104of the tubular drive stack60and drive shaft72also along the axis of intersection (indicated by arrow160) but diametrically opposite from the first opening162. The second keyhole opening164also results from the intersection of the cooperating drive and reaction slots110and114and lies along the axis of intersection (indicated by arrow160). The keyhole opening164is substantially aligned with the second of the crosswise apertures138in the collar134of the handle18on an opposite side of the device10from the first crosswise aperture138, and the drive pin16is then passed into and through the second of the crosswise apertures138.

According to a second method for installing the drive pin16, the handle18is rotated on the drive base12about the device operational drive axis52only until the drive pin16encounters one of the drive slots110in the side wall102of the tubular drive stack60. Thereafter, light pressure is applied to the drive pin16along its longitudinal axis166normal to the device operational drive axis52. The pressure (indicated by arrow158) applied to plunger assembly14along the device operational drive axis52is alternately increased or decreased appropriately until the axis of intersection (indicated by arrow160) between the cooperating drive and reaction slots110and114coincides with the longitudinal axis166of the drive pin16. This coincidence of the axis of intersection (indicated by arrow160) with the drive pin longitudinal axis166occurs when the drive shaft72is positioned relative to the drive stack60along the device operational drive axis52such that the reaction slot114intersects the with the longitudinal axis166of the drive pin16. The pressure (indicated by arrow158) applied to plunger assembly14is held steady while the drive pin16is pushed through an opening in the respective side walls102and104of the tubular drive stack60and drive shaft72along the axis of intersection (indicated by arrow160) that results from the intersection of the cooperating drive and reaction slots110and114. The drive pin16is passed through the chamber116within the drive shaft72and through another opening in the respective side walls102and104of the tubular drive stack60and drive shaft72also along the axis of intersection (indicated by arrow160) but opposite from the first opening and also resulting from the intersection of the cooperating drive and reaction slots110and114. The drive pin16is then passed into and through the second of the crosswise apertures138in the collar134of the handle18on an opposite side of the device10from the first crosswise aperture138. According to either assembly method, the pressure (indicated by arrow158) applied to plunger assembly14is relieved, which permits the suction cup74to return to its relaxed state. The novel suction cup device10is ready for action.

FIG. 5is an exploded view that illustrates assembly of the novel suction cup device10. As disclosed herein, if present the optional rotational drive member or “handle”18is fit over the bell shaped drive base12along the device operational drive axis52. The optional spring or other biasing mechanism124is compressed between the optional plate or disk132or the end118of the drive shaft72. The guides96in the form of one or more slides or keys100mating with corresponding slots or keyways98align the plunger drive shaft72and mating tubular drive stack60of the suction cup drive base12. The drive shaft72is pushed into the drive stack60of the drive base12by application of pressure (indicated by arrow158) along the device operational drive axis52, which simultaneously compresses the biasing mechanism124therebetween. The drive pin16is inserted through the crosswise apertures138in the collar134of the handle18along the axis of intersection (indicated by arrow160) between the cooperating drive and reaction slots110and114. The pressure (indicated by arrow158) applied to plunger assembly14is relieved, whereupon the suction cup74returns to its relaxed state and the novel suction cup device10is ready for action.

FIG. 6is an overhead exploded pictorial view that also illustrates assembly of the novel suction cup device10. Here, the inner tubular walled aperture136of the handle collar portion134is shown to be sized to fit over the sphere22and upright post24of the utilization mounting surface20and spin freely about the drive stack outer wall portion102.

FIG. 7is an underneath exploded pictorial view that also illustrates assembly of the novel suction cup device10. Here, the guides96are formed between the tubular drive shaft72and the mating suction cup drive base12. For example, are provided as one or more slots or mating keyways98and keys100the guides96are illustrated for initially aligning the tubular drive shaft72with the mating suction cup drive base12and subsequently maintaining alignment therebetween. Here, by example and without limitation, the keyways98are recessed into opposite internal faces of an outer wall portion102forming the tubular drive stack60, and the mating keys100are formed on the wall portion104of the tubular drive shaft72.

FIG. 8is another underneath exploded pictorial view that illustrates assembly of the novel suction cup device10. Here, the outer wall portion102forming the tubular drive stack60, and the cooperating wall portion104of the tubular drive shaft72are alternatively formed with optional mating nonround shapes. By example and without limitation substantially rectangular or square shapes are illustrated for the cooperating wall portions102and104. Accordingly, the tubular drive shaft72and cooperating tubular drive stack60mate in a sliding fit only along the device operational drive axis52, whereby mutual revolution about the device operational drive axis52is impossible. Furthermore, the guides96are provided as mating corners168and170, and mating wall features172and174between the internal faces of the wall portion102forming the tubular drive stack60and the wall portion104forming the drive shaft72. The aperture128in the drive stack floor portion62is a complementary nonround shape. The mating nonround corner features168and170and wall features172and174accordingly provide initial alignment between the tubular drive shaft72and the mating suction cup drive base12, and subsequently maintain alignment therebetween.

While the preferred and additional alternative embodiments of the invention have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. Therefore, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. Accordingly, the inventor makes the following claims.