Patent Description:
An o-ring is a loop of elastomer, typically with a round cross-section, that is seated in a groove and compressed during assembly between two or more parts. O-rings are typically used to create a seal at the interface of these two or more parts. This seal between assembled parts may prevent fluids or air from passing through the interface. Thus, without properly installed o-rings, leaks and product failures may occur.

Common problems that occur during o-ring installation may include tears, twisting and turning, and overstretching. O-rings that are small are more prone to tearing and twisting. O-rings that are large do not provide an adequate seal unless very precisely placed. Further, installation of o-rings onto features having threads, tabs, corners or edges resent substantial complexity in the known art, as tearing during such installations is very prevalent.

Each o-ring has a maximum stretch point, based on its composition, diameter, etc. Overstretching causes o-rings to break or tear during assembly or use. Similarly, unevenly stretched o-rings may tear, or may affect a poor seal. Thus, each o-ring should be stretched evenly and only to the extent necessary to achieve a very precise fit upon placement.

Additionally, upon installation, simply rolling an o-ring off of a shaft may lead to spiraling, twisting or turning of the o-ring. Spiraled or twisted o-rings result in leaks and/or damage to the finished assembly. Sliding an o-ring into place, rather than rolling it, helps avoid spiraling and twisting. However, sliding requires more complex installation equipment, as well as the use of significant amounts of expensive lubricant.

The use of robotics is well established as a manufacturing expedient, particularly in applications where human handling is inefficient and/or ineffective-such as during the precise placement of o-rings. <CIT> discloses an o-ring gripping end effector. Current practice to robotically install o-rings using end effectors suffers from all of the disadvantages referenced above-namely, the tendency to often tear, spiral or twist the o-ring. This is the case because current end effectors do not provide an accounting for the variability in the sizes, shapes and composition of end effectors, and further do not account for variances in pickup or placement locations or location sealing-needs.

Accordingly, there is a need for an improved o-ring gripper.

Certain embodiments are and include an apparatus, system and method for providing an o-ring gripper. The embodiments includes an o-ring gripping end effector, comprising: a housing; a movable stripping bar mechanically associated with the housing; a plurality of modules at least partially within the housing wherein each of the modules comprises: a module head extending at least partially through the movable stripping bar distally from the housing, and comprising at least one retention groove for retaining the o-ring and at least four fingers that each provide a portion of the at least on retention groove and at least two interleaved angular jaws, wherein each of the at least two jaws provides at least two of the at least four fingers, and wherein an increase in angle between the at least two jaws effects an expansion of an area bounded by each of the at least four fingers; wherein the stripping bar is configured to move distally from the housing and thereby strip an ring from the retention groove for placement.

An o-ring gripping end effector may comprise a robot associated with the end effector opposite the housing. The robot may be part of an assembly line and the assembly line may be a consumer products assembly line or an automotive parts assembly line.

Thus, the disclosure provides at least an apparatus, system and method for providing an improved o-ring gripper.

The exemplary compositions, systems, and methods shall be described hereinafter with reference to the attached drawings, which are given as non-limiting examples only, in which:.

The figures and descriptions provided herein may have been simplified to illustrate aspects that are relevant for a clear understanding of the herein described apparatuses, systems, and methods, while eliminating, for the purpose of clarity, other aspects that may be found in typical similar devices, systems, and methods. Those of ordinary skill may thus recognize that other elements and/or operations may be desirable and/or necessary to implement the devices, systems, and methods described herein. But because such elements and operations are known in the art, and because they do not facilitate a better understanding of the present disclosure, for the sake of brevity a discussion of such elements and operations may not be provided herein. However, the present disclosure is deemed to nevertheless include all such elements, variations, and modifications to the described aspects that would be known to those of ordinary skill in the art, as long as these elements, variations and modifications do not depart from the scope of the appended claims.

Embodiments are provided throughout so that this disclosure is sufficiently thorough and fully conveys the scope of the disclosed embodiments to those who are skilled in the art. Numerous specific details are set forth, such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. Nevertheless, it will be apparent to those skilled in the art that certain specific disclosed details need not be employed, and that embodiments may be embodied in different forms. As such, the disclosed embodiments should not be construed to limit the scope of the disclosure. As referenced above, in some embodiments, well-known processes, well-known device structures, and well-known technologies may not be described in detail.

For example, as used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The steps, processes, and operations described herein are not to be construed as necessarily requiring their respective performance in the particular order discussed or illustrated, unless specifically identified as a preferred or required order of performance. It is also to be understood that additional or alternative steps may be employed, in place of or in conjunction with the disclosed aspects.

When an element or layer is referred to as being "on", "upon", "connected to" or "coupled to" another element or layer, it may be directly on, upon, connected or coupled to the other element or layer, or intervening elements or layers may be present, unless clearly indicated otherwise. In contrast, when an element or layer is referred to as being "directly on," "directly upon", "directly connected to" or "directly coupled to" another element or layer, there may be no intervening elements or layers present. Further, as used herein the term "and/or" includes any and all combinations of one or more of the associated listed items.

Yet further, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the embodiments.

The embodiments provide a modular o-ring gripper system. Each module may pick, stretch and place a single o-ring, and may include a module head that includes multiple jaw-fingers provided by two interleaved angular grippers. To provide optimal finger expansion/retraction, the gripper jaw bases may be positioned between <NUM> and <NUM> degrees, such as at <NUM> degrees, apart at their respective front faces, and may be staggered vertically, such as by <NUM>-<NUM>, such as by <NUM>, to allow for interleaving.

This interleaving may provide, for example, <NUM> jaw fingers that may spread rectangularly / ovalarly. By way of example, these <NUM> jaw fingers may spread an oval o-ring into a rectangular contour that ultimately fits over an oval shaped housing.

The design of the jaw fingers, and consequently the angle and interleaving, for each module may be unique to each desired contour of a picked and placed o-ring. For example, the desired stretched position of the o-ring at full open may be assessed, and then the jaws, and consequently the jaw fingers, may be configured around each other to achieve this stretch of the o-ring.

The modules can be arranged in clusters of similar or dissimilar types, depending on the application. For example, four, six or eight modules may be arranged in a row on a particular end effector that carries the modules.

Each module head, and correspondingly its gripper fingers, present a common "groove" that retains the o-ring without slipping until a stripping bar of the module housing comes down to strip and place the o-ring. That is, in order to strip the o-rings off of the fingers, the stripping plate of the stripping bar is brought down over the module head, and correspondingly the fingers, to force all o-rings off of their respective jaw fingers once that module head is in position for proper dispensing.

One advantage of the embodiments is the ability to place multiple o-rings at a time, even if they are of different sizes, with a very compact end effector. Thereby, the embodiments save on the cost of extra production work stations, decrease assembly-line length by allowing for the placement of all payload at once, and are translatable across many configurations of parallel pallet tooling.

The embodiments allow for dispensing of both commonly shaped and sized o-rings, as well as of small and/or irregularly shaped o-rings. By way of example, the disclosed translation allows uniquely for o-ring stripping even if the target part has flanges or tabs to hook onto the o-ring.

O-rings are typically elastic bands, such as being formed of rubber or polyurethane, which are placed in a variety of manufacturing applications. Dispensing may occur onto metallic or plastic components, by way of example, such as on a high speed conveyor pallet. In the embodiments, these o-rings may be placed in multiples, such as four, six, or eight at a time, by way of non-limiting example.

The embodiments may be employed on any production line that inserts o-rings and/or o-ring seals. Products created on such production lines include consumer products, automotive parts such as fuel injectors, and the like. In addition to o-rings, any other complaint/elastic parts can be handled using the disclosed embodiments.

<FIG> illustrate a multi-position modular end effector for o-ring placement <NUM>. The illustrations show a <NUM>-position modular construction, although it will be appreciated that other multiples of modules may be included. Moreover, although the o-rings <NUM> shown are of the same type and size in association with each module, it will be understood that ones of the modules <NUM> may be dedicated to an o-ring <NUM> of a different size or type.

As illustrated, each module <NUM> may comprise a "head" 14a onto which the o-ring <NUM> is placed for dispensing. The head 14a may preferably be formed of multiple "fingers" <NUM> extending outwardly from each module <NUM>, and more particularly from a jaw base <NUM> or jaw bases of each module <NUM>, into each o-ring <NUM>.

Each module head 14a may have, at the portion extended through the o-ring <NUM> to grasp it, a "mushroom cap" <NUM> feature. This mushroom cap <NUM> feature may be formed of the distal-most aspects (from the end effector main housing) of respective ones of the jaw fingers <NUM>, in conjunction.

Thereby, each module head 14a may comprise one or more "grooves" <NUM> into which each o-ring <NUM> is seated when picked, and from which each o-ring <NUM> is removed when dispensed. That is, the jaw fingers <NUM> may form a "groove" <NUM> just below the mushroom cap <NUM>.

As such, each module <NUM> may have the actuating power and electrical, mechanical and electromechanical (collectively, "electromechanical") aspects <NUM> thereof at least partially resident within the end effector housing <NUM>. These electromechanical aspects <NUM> may include actuation aspects for actuating each module <NUM>, such as actuating the interleaved jaws <NUM> from which the fingers <NUM> extend, as discussed further herein below. The end effector housing <NUM> may additionally include features for mechanical association with production line robotics <NUM> that may move and/or power the end effector.

Also associated with the end effector housing <NUM> may be a stripping bar <NUM>. In embodiments, each module head <NUM> may preferably at least partially extend through a respectively dedicated opening in a stripping plate 52a of this stripping bar <NUM>, such that a downward movement of the snugly-fit opening about that module <NUM> on the stripping plate 52a effects a slide of a retained o-ring <NUM> over the mushroom cap <NUM> and onto the placement location. The opening in the stripping plate 52a can also be a window. The stripping plate 52a may comprise a plurality of windows therein.

More specifically, after picking of an o-ring <NUM> and upon positioning of the o-ring <NUM> upon the module head 14a for proper dispensing, the end effector housing <NUM> may have features for executing a downward movement of the stripping bar <NUM> over the extended portion of the module head 14a, i.e., the mushroom cap <NUM> of the module head 14a. Upon this downward movement, each o-ring <NUM> is stripped from its groove(s) <NUM> for dispensing. This stripping may further include, for example, a contraction of the jaw fingers <NUM> grasping the o-ring <NUM>, thereby decreasing the circumference of the mushroom cap <NUM> and consequently more efficiently dispensing the o-ring <NUM>, or an expansion of the jaw fingers <NUM>, such as to further but briefly stretch an o-ring <NUM> into a proper shape or circumference for dispensing.

In particular, <FIG> illustrates a side-view of the end effector housing <NUM>, the stripping bar <NUM>, the extended module head 14a, and interleaved jaws <NUM> that may present the jaw fingers <NUM> for each module head 14a. As is evident from the embodiment from <FIG>, the stripping bar <NUM> may be actuated downward over each module head 14a by any of a variety of methodologies, such as a mechanical cam, an interleaved slide, pneumatics, or the like, by way of non-limiting example.

<FIG> shows a bottom view of the disclosed modular o-ring gripping module <NUM>. In this illustration, the stripping bar <NUM> is extended downward to reach, and subsequently pass over, the retaining groove(s) <NUM> for each o-ring <NUM>. This extension of the stripping bar <NUM> effectuates a shedding of the o-rings <NUM> for dispensing.

Also included in the embodiment of <FIG> are two interleaved jaws <NUM>, each having <NUM> jaw fingers <NUM>, wherein each jaw-base <NUM> for each module extends outwardly substantially axially perpendicular to the longitudinal axis of the stripping bar <NUM>. Although the jaws <NUM> of each module <NUM> are shown as fixed within the end effector housing <NUM> in <FIG>, it will be understood that the module <NUM> and/or its respective jaws <NUM> may be movable and/or float within the end effector housing <NUM>.

More specifically, additional functionality may be added by mounting each module to a floating air bearing to allow it to "float" in the x-y-z axes and/or in theta. This float may be monitored by cameras, such as to provide vision/machine vision, both for acquiring o-rings (or like-parts) and for placing o-rings. This camera may be associated with the end effector housing in order to adjust each module head for optimal picking and placement. Thereby, variances in product upon pick and place can be mitigated by compensating the module position.

<FIG> illustrates two interleaved jaws <NUM>, each providing two jaw fingers <NUM>. These interleaved jaws <NUM> are angled in the illustration. The angular jaws <NUM> may be then overlapped as shown such that, upon rotation of either or both of the angled jaw bases <NUM>, the fingers <NUM> of both jaws <NUM> cause an expansion or retraction of the module head/mushroom cap <NUM> (dependent upon the angle of rotation of the jaw bases with respect to one another).

More particularly, angled gripper jaws may provide: a long stroke across the <NUM> total jaw fingers, thereby enabling substantial stretching and/or shaping of a retained o-ring; as well as providing a very tight jaw finger closed position. As will be appreciated by the skilled artisan, this <NUM> finger configuration thus allows for translation of the o-ring in both the x and y axis, rather than the simple single-axis translation provided by the known art.

The enhanced retraction/expansion of the module head provided by the embodiments causes a correlated retraction/expansion of the o-ring retained in the groove(s) of that module head. In the example of <FIG>, the o-ring <NUM> is shown at its full expanded shape and circumference available from the illustrated jaw finger configuration, while the jaw fingers <NUM> are shown as retracted.

<FIG> is a side-view illustration of the embodiment of <FIG>. As is evident, the offsetting of the angular jaw heads <NUM> provides an interleaving of the jaw fingers <NUM> as referenced above, thereby enabling the contraction/expansion of the mushroom cap <NUM> presented by the fingers <NUM> upon a rotation of either or both of the jaw heads <NUM>.

<FIG> illustrate a picking and placement sequence for the disclosed modular o-ring gripper system <NUM>. In short, the o-ring <NUM> is presented, picked by the module head 14a, stretched as needed for placement by the angular jaws' fingers <NUM>, positioned for placement, and placed by extension of the stripping bar <NUM>. After these steps, the modular gripper <NUM> may depart and return to the picking location to pick o-rings <NUM> anew.

More particularly, and as illustrated in <FIG>, the o-ring <NUM> is picked, typically via an expansion of the fingers <NUM> upon insertion of the previously-contracted module head 14a through the o-ring <NUM>. That is, typically, the contracted jaw fingers <NUM> are inserted through the o-ring <NUM> for grasping of the o-ring <NUM>.

<FIG> illustrates the positioning of the jaw fingers <NUM> over a grooved product seat <NUM> for the o-ring <NUM>. <FIG> illustrates the setting of the o-ring <NUM> on the module head groove <NUM> upon the groove <NUM> of the grooved product seat <NUM>, i.e., the positioning of the module head 14a and the o-ring <NUM> for eventual placement of the o-ring <NUM>.

As shown in <FIG>, the stripping bar <NUM> then comes down to depart that o-ring <NUM> from the jaw fingers <NUM> onto the grooved product seat <NUM>. The stripping bar <NUM> may then retract, and the end effector <NUM> may depart the seating location.

The foregoing apparatuses, systems and methods may also include the control of the various robotic and gripping functionality referenced throughout. Such control may include, by way of non-limiting example, manual control using one or more user interfaces, such as a controller, a keyboard, a mouse, a touch screen, or the like, to allow a user to input instructions for execution by software code associated with the robotics and with the systems discussed herein. Additionally, and as is well known to those skilled in the art, system control may also be fully automated, such as wherein manual user interaction only occurs to "set up" and program the referenced functionality, i.e., a user may only initially program or upload computing code to carry out the predetermined movements and operational sequences discussed throughout. In either a manual or automated embodiment, or in any combination thereof, the control may be programmed, for example, to relate the known positions of substrates, the robotics, the stationary point, and the relative positions there between, for example.

It will be appreciated that the herein described systems and methods may operate pursuant to and/or be controlled by any computing environment, and thus the computing environment employed not limit the implementation of the herein described systems and methods to computing environments having differing components and configurations. That is, the concepts described herein may be implemented in any of various computing environments using any of various components and configurations.

Further, the descriptions of the disclosure are provided to enable any person skilled in the art to make or use the disclosed embodiments. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the appended claims.

Claim 1:
An o-ring gripping end effector (<NUM>), comprising:
a housing (<NUM>);
a movable stripping bar (<NUM>) mechanically associated with the housing (<NUM>);
a plurality of modules (<NUM>) at least partially within the housing (<NUM>), each of the modules (<NUM>) comprising:
a module head (14a) extending at least partially through the movable stripping bar (<NUM>) distally from the housing (<NUM>), and comprising at least one retention groove (<NUM>) configured to retain an o-ring (<NUM>) and at least four jaw fingers (<NUM>) that each provide a portion of the at least on retention groove (<NUM>);
at least two interleaved angular jaws (<NUM>), wherein each of the at least two jaws (<NUM>) provides at least two of the at least four jaw fingers (<NUM>), and wherein an increase in angle between the at least two jaws (<NUM>) effects an expansion of an area bounded by each of the at least four jaw fingers (<NUM>);
wherein the stripping bar (<NUM>) is configured to move distally from the housing (<NUM>), and thereby strip an o-ring (<NUM>) from the retention groove (<NUM>) for placement.