Adjustable height workstation

Information

  • Patent Grant
  • 6575212
  • Patent Number
    6,575,212
  • Date Filed
    Friday, April 27, 2001
    23 years ago
  • Date Issued
    Tuesday, June 10, 2003
    21 years ago
Abstract
A workstation having an adjustable support structure is disclosed. The workstation includes a beam, a position locking apparatus, and a workpiece-supporting device slideable along the beam to a position where it is locked by the locking apparatus. The locking apparatus is configured to exert a constraining force proportional to a load force. Also disclosed is a workstation including a means for supporting a workpiece, a means for supporting a means for supporting the workpiece at a selected distance above a floor, and a means for frictionally securing the means for supporting the workpiece to the means for supporting the means for supporting the workpiece. Also disclosed is a workstation including a vertically disposed support member and at least one tooling plate assembly including a position securing apparatus for securing the tooling plate assembly in a selected vertical position and including wedging surfaces cooperating in frictionally securing the tooling plate assembly to the support member, wherein the securing force corresponds to the loading force.
Description




A. FIELD OF THE INVENTION




The present invention generally relates to the field of workstations, and more particularly to heavy duty workstations for modular assembly cells having work surfaces of which the height above a supporting floor is adjustable.




B. BACKGROUND OF THE INVENTION




Workstations, also known as manufacturing cells, are often used in manufacturing facilities for operations on workpieces and for assembling parts to form assemblies or subassemblies. Workstations may be configured in a manner similar to that of conventional workbenches, typically having a generally flat work surface or platform for holding a workpiece while performing manufacturing operations such as fabricating, drilling, assembling, etc. Workstations may also be configured to include manufacturing tooling (e.g., an air cylinder, a power drill, screwdriver, or nut runner, riveting or spot-welding apparatus, etc.), instrumentation and/or control apparatus (e.g., for monitoring and controlling a manufacturing process or characteristic of the workpiece), parts and product bins, trays, conveyors, etc.




In the past, workstations were typically designed and built for a particular manufacturing application or procedure. In most cases, the height of the work platform is fixed. The workstation or cell is normally constructed by mounting a support structure to a table. The table may be constructed from welded steel, or assembled from aluminum extrusion or steel tubing. The workstation tooling is typically mounted to the support structure in a fixed location above the work platform at an average height normally required for the assembly operation. Since each workstation is normally associated with a particular manufacturing function and a unique workpiece, the height of the support structure necessarily varies for nearly every workstation. The type of the tooling also varies from workstation to workstation. Hence, numerous different designs for the workstation support structure are often required to accommodate a single manufacturing line.




Furthermore, different workstation operators may be assigned at different times to work at a particular workstation, and all operators are obviously not the same height. Since a particular workstation may be used for assembling different products having different heights at different times, it is therefore desirable for the height of the working surface to be adjustable above the floor. Preferably, the height would be infinitesimally adjustable, or at least adjustable in small increments to accommodate all operators. Most fixed-height workstation constructions are not easily re-configurable to make them adjustable in height. The fixed working height of most known workstations creates a less than ideal ergonomic situation for the operators.




Some commercially available workstations are designed to have work surfaces adjustable in height. However, such workstations have numerous disadvantages. First, adjustable-height workstations have generally been of relatively small capacities in terms of weight and force that the adjustable work surface can support, e.g., often having a support capacity of less than 1000 pounds. Second, those few heavy-duty workstations that are height-adjustable are usually only adjustable in large increments. Third, such heavy-duty workstations have been relatively expensive. Fourth, those workstations that are infinitesimally adjustable in height are usually not heavy duty, and therefore tend to slip under increased loads. Fifth, known workstations often require a difficult or involved procedure to adjust the height to a different operator or workpiece. Sixth, workstations that are provided with tooling for manufacturing a particular product generally had the tooling affixed in a manner that makes it difficult to remove and replace with different tooling for another product. These disadvantages present significant difficulties in implementation of flexible manufacturing cell concepts and practices.




A need, therefore, exists for an infinitesimally adjustable-height work surface for a workstation that is very rugged in construction to accommodate relatively heavy workpieces and large forces, that can be adjusted quickly and easily to accommodate flexible manufacturing cell environments, and that is relatively inexpensive and easy to manufacture.




C. OBJECTS AND SUMMARY OF THE INVENTION




It is an object of the present invention to provide a workstation having a work surface that is infinitesimally adjustable in height with respect to a supporting floor.




It is another object of the present invention to provide an adjustable-height workstation that is ruggedly constructed and has a workpiece weight capacity and manufacturing force capacity exceeding 1000 pounds.




It is a further object of the present invention to provide a workstation in which an increase in a load force causes a corresponding increase in a work surface securing force to prevent slippage.




It is still another object of the present invention to provide a rugged, adjustable-height workstation that is relatively inexpensive to manufacture.




It is yet another object of the present invention to provide a workstation that facilitates the use of manufacturing tooling that can be easily removed and replaced to enable manufacturing of different products at the same workstation.




Accordingly, the present invention provides a workstation that is designed to be both height-adjustable for different operators and re-configurable for different products. In the preferred embodiment, the base structure of the workstation is constructed from a relatively inexpensive weldment and a vertical column composed of a standard structural steel I-beam. Only minimal machining of this I-beam is required to manufacture the workstation. A steel tooling plate is vertically disposed and mounted to the vertical column using channels such that it is able to slide vertically. A horizontal platform, along with the necessary support structure, is mounted to the vertical tooling plate to provide the work surface for the workpiece. Alternatively, a horizontal platform can be used that supports a conveyor when a part transport system is required. A locking wedge mechanism is located between the vertical column and the vertically disposed tooling plate to frictionally engage the surface of the column. This locking wedge allows the tooling plate to be positioned anywhere within a range along the vertical column and then locked. The vertical adjustment can be made using a hydraulic jack permanently attached to the workstation, or using a crane or forklift. The locking wedge mechanism allows for extremely heavy tooling or workpieces to be securely affixed to the vertical tooling plate, while maintaining its ability to be readily adjusted along the vertical column.




Another embodiment of the present invention provides a support structure for a work surface, the support structure including a beam having a length and a surface, a position securing apparatus, and a workpiece-supporting device. The workpiece-supporting device is configured to be slidably restrained to the beam and to be secured to the beam in selected positions along the length of the beam by the position securing apparatus. The position securing apparatus is configured to constrain the workpiece-supporting device in the selected position notwithstanding the presence of a load force having a line of action parallel to the longitudinal axis of the beam. The position securing apparatus is further configured to exert a constraining force that is proportional to the load force.




Still another embodiment of the present invention relates to a workstation including a means for supporting a workpiece, and a means for supporting the means for supporting the workpiece at a selected distance above a floor. The workstation also includes a means for frictionally securing the means for supporting the workpiece to the means for supporting the means for supporting the workpiece at the selected distance. The means for frictionally securing includes a first surface frictionally bearing upon a second surface.




Yet another embodiment of the present invention relates to a workstation including a vertically disposed support member and at least one generally vertically disposed tooling plate assembly. The tooling plate assembly includes a tooling plate and a position securing apparatus for securing the tooling plate in a selected vertical position with respect to and upon the support member. The position securing apparatus includes first and second wedging surfaces configured to cooperate in frictionally securing the tooling plate to the support member. The first and second wedging surfaces are disposed to be engaged in a downward direction of movement of one of the first and second wedging surfaces. An increase in downward force upon the tooling plate increases engagement of the first wedging surface with the second wedging surface and increases frictional securing force, the securing force thereby corresponding to the loading force.











D. BRIEF DESCRIPTION OF THE DRAWINGS




The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention itself, however, together with further objects and advantages thereof, may best be understood by reference to the following description when taken in conjunction with the accompanying drawings in which:





FIG. 1

is a perspective view of an exemplary embodiment of the invention showing a workstation having a work surface adjustable in height above a supporting floor, and having parts bins disposed for rear loading and unloading;





FIG. 2

is a perspective view of the embodiment of the workstation shown in

FIG. 1

, except having the parts bins replaced by a transversely disposed conveyor;





FIG. 3

is a front elevational view of the adjustable height workstation shown in

FIG. 1

;





FIG. 4

is a side elevational view of the workstation shown in

FIG. 1

;





FIG. 5

is a top plan view of the workstation shown in

FIG. 2

;





FIG. 6

is a partial, cross-sectional view of the tooling plate and wedge assembly taken across line


6





6


of

FIG. 3

;





FIG. 7

is a partial, front elevational view of the tooling plate and wedge assembly illustrated in

FIG. 6

; and





FIG. 8

is an exploded, partial perspective view of the wedge assembly illustrated in FIGS.


6


and


7


.











E. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring now to the drawings,

FIGS. 1 through 5

show a workstation


10


including a fixed support structure


12


and a movable support structure


14


. Fixed support structure


12


comprises a base


16


and a support member


18


. Since the preferred method of performing assembly operations is in the vertical direction, the support member


18


in the preferred embodiment is comprised of a beam or column that is configured to extend vertically up from the base


16


. Movable support structure


14


functions as a backbone assembly and comprises a tooling plate


20


, and typically includes either a worktable


22


or tooling


24


, or both, affixed thereto. As known in the art, tooling


24


is used to perform machining or assembly operations upon a workpiece


26


mounted or resting upon worktable


22


. Tooling


24


could be attached to or associated with either fixed support structure


12


or movable support structure


14


, depending upon the particular workstation application. In the preferred embodiment, tooling plate


20


is oriented vertically instead of horizontally, since it is typically much easier to mount tooling


24


to a vertically oriented tooling plate in most workstation applications. However, as will be discussed below, the present invention is not limited to those workstations having a vertical tooling plate configuration.




Optional accessories may be attached to either fixed support structure


12


or movable support structure


14


. In

FIGS. 1-5

, a safety guard structure


28


, constructed from aluminum extrusion, is affixed to tooling plate


20


such that it moves vertically with the tooling plate. A process control and display unit (CDU)


30


may be attached to the guard structure


28


. In another embodiment, the guard structure


28


is attached to the fixed support structure


12


, either by mounting it to base


16


or to support member


18


. In this embodiment, the guard structure


28


would be lifted away from the workstation


10


in order to change the tooling for a different application.




Other accessories can also be attached to either fixed support structure


12


or movable support structure


14


, such as parts and product containers. The narrow width of support member


18


allows for parts to be fed on either side of the tooling plate


20


. The configuration of

FIG. 1

is also useful for modular assembly cells that have the required parts brought to the operator in bins


32


. These bins are loaded into the workstation from the rear so that the assembly operation is not interrupted. In

FIG. 2

, a portion of the production line apparatus, shown as a workpiece conveyor


34


, is designed to pass through the guard structure


28


for a different assembly application. Hence, as can now be appreciated, workstation


10


of the present invention is very flexible in its configuration such that it can readily be adapted for a wide variety of modular cell applications.




As shown in

FIG. 3

, base


16


is preferably configured as a welded steel fabrication supported by leveling screws


36


positioned upon sole plates


38


. The sole plates are securely mounted to the floor in compliance with Occupational Safety and Health Administration (OSHA) regulations. Base


16


may be fabricated of low-carbon steel plate and/or structural steel sections (e.g., channels or plates).




Support member


18


is comprised of an elongated structural member, such as a structural steel beam or column. In the preferred embodiment, support member


18


is a steel beam having wide flanges, such as a standard “I-beam” or “H-beam” that is typically used for columns in building construction. In an alternative embodiment (not shown), support member


18


may be constructed from any conventional wide flange beam, C-shaped or S-shaped beam stock, square or rectangular cross-section steel tube, etc. Support member


18


could also be comprised of a pair of separate parallel rails or ways, as known in the art. Support member


18


is rigidly affixed (e.g., by welding, using bolts, with brackets, etc.) to base


16


. Additional gussets (not shown) may be added, if desired, to further secure support member


18


to base


16


.




Movable support structure


14


is slidably engaged upon fixed support structure


12


. As can most easily be seen in

FIG. 4

, tooling plate


20


in the preferred embodiment is attached to the vertical support member


18


using guiding assemblies


40


that grasp the inner edges


18




b


of the beam flanges in such a way that the tooling plate


20


can slide up and down. As will be described below, it is the combination of this guide assembly and a wedge assembly that engages with the I-beam and locks the tooling plate in a fixed position.




In the preferred embodiment of the present invention, tooling plate


20


is fabricated from a steel plate. Horizontal worktable


22


is affixed to the vertically oriented tooling plate


20


, as most clearly illustrated in

FIGS. 3-6

. Worktable


22


is also constructed of a steel plate. Worktable


22


is disposed on a pair of triangularly shaped support brackets


42


that are mounted to tooling plate


20


and worktable


22


using bolts, as shown in FIG.


4


. Hence, worktable


22


will slide vertically along support member


18


with tooling plate


20


. Tooling plate


20


also includes a plurality of threaded apertures to receive standard machine screws (not shown) for attachment of tooling


24


.




As shown in

FIGS. 1 and 4

, both the tooling


24


and the worktable


22


are mounted to tooling plate


20


such that the entire movable support structure


14


moves vertically along the fixed support member


18


. A major benefit of this configuration is that the workstation is easily retooled, i.e., when the modular cell system needs to be retrofitted for a new product, the new tooling is assembled on a second tooling plate and the entire backbone assembly unit is quickly exchanged for the old assembly unit. This is accomplished by removing the guard structure


28


, lifting off the old movable support structure


14


, and installing the new movable support structure.




In

FIG. 2

, tooling


24


is affixed to tooling plate


20


, but no worktable


22


is used in this embodiment. Conversely, in

FIG. 3

, worktable


22


is affixed to tooling plate


20


but no tooling


24


is used. Hence, it can be seen that either or both the tooling


24


and/or worktable


22


can be mounted to the same tooling plate


20


, or that two individual tooling plates could be used. Furthermore, depending upon the particular workstation application, the orientation of the tooling plate


20


may be changed. In the preferred embodiment, the tooling plate


20


is oriented vertically instead of horizontally, since it is typically much easier to mount tooling to a vertical tooling plate. However, the present invention is not limited to having a vertically oriented tooling plate configuration. For example, a horizontally mounted tooling plate configuration, where the longitudinal axis of the support member


18


is horizontal, would be preferable for horizontally disposed tooling such as a horizontal milling machine.





FIGS. 6 and 7

illustrate how the tooling plate


20


is mounted to support member


18


. Movable support structure


14


includes tooling plate


20


and at least two guiding assemblies


40


, one on each side of the beam. In the preferred embodiment, four guiding assemblies


40


are used, each separated from the others on the tooling plate


20


as shown in FIG.


3


. Each pair of guiding assemblies


40


is positioned on tooling plate


20


to engage the corresponding edges of the flanges of support member


18


. Four large guide pins


44


, each comprised of a dowel pin pressed into an aperture in the tooling plate


20


in an interference fit, serve to slide along the edges of the I-beam flange as the tooling plate


20


is raised and lowered. One guide pin


44


is positioned near each corner of the tooling plate


20


, as shown in

FIG. 3

, such that they appropriately guide the tooling plate to prevent binding and misalignment.




Each guiding assembly


40


includes a clamping plate


46


, two clamping screws


48


, two pivot studs


50


, and a bearing plate


52


, as most clearly shown in FIG.


7


. Each clamping plate


46


has two clearance holes


54


near its center line that are unthreaded and slightly larger in diameter than the major thread diameters of clamping screws


48


for passage of the clamping screws. Tooling plate


20


includes corresponding threaded apertures


56


for receiving threaded portions of clamping screws


48


. Pivot studs


50


are threaded into tooling plate


20


as shown, such that they are positioned near the outermost edge of the clamping plate


46


. Finally, bearing plate


52


, having two clearance holes


58


similar to those of clamping plate


46


, is positioned between the rear face of the tooling plate


20


and the clamping plate


46


. Bearing plate


52


is constructed of a material having a low coefficient of friction and a relatively high wear rate, such as an ultra-high molecular weight (UHMW) polymer. One surface of bearing plate


52


is clamped against the flange of I-beam


18


by the clamping plate


46


.




Using this configuration, the tooling plate


20


, clamping plate


46


, clamping screw


48


, pivot stud


50


, and bearing plate


52


cooperate to form guiding assembly


40


which can be closed by tightening clamping screws


48


. This causes the outer side of clamping plate


46


to pivot about the outermost tip of pivot stud


50


and the inner side of the clamping plate


46


to press the bearing plate


52


against the inner side of the flange of I-beam


18


to form a channel guide. This guiding assembly, in conjunction with guide pins


44


, allows the tooling plate


20


to be movable and positioned anywhere along the center portion of I-beam


18


without an undesirably large amount of lateral play or looseness. As will be seen below, the weight of the tooling plate


20


is supported by a wedge-shaped piece of steel that is trapped between the front face


18




a


of I-beam


18


and a rear surface


20




b


of tooling plate


20


.




As shown in

FIGS. 6 through 8

, movable support structure


14


also includes a wedge assembly


60


which, in the preferred embodiment, is housed within a lower portion of tooling plate


20


. Wedge assembly


60


includes a wedge plate


62


and a recess or pocket


64


disposed within the rear surface


20




b


of tooling plate


20


, which is facing the front surface


18




a


of I-beam


18


. The recess floor


64




a


of pocket


64


is generally flat but is sloped at a predetermined angle from the rear surface


20




b


of tooling plate


20


. Wedge plate


62


is housed within pocket


64


. Wedge plate


62


also has a sloping surface


62




a


having an angle complementary to that of recess floor


64




a


. As will be seen below, recess floor


64




a


functions as a first wedging surface, and the sloping surface


62




a


of wedge plate


62


functions as a second wedging surface. In the preferred embodiment, the rear surface


62




b


of wedge plate


62


is serrated to ensure that the wedge plate does not slip along the front surface


18




a


of the I-beam


18


.





FIG. 7

illustrates that wedge plate


62


is disposed inside pocket


64


and arranged such that the wider portion of both pocket


64


and wedge plate


62


are oriented downwards. If wedge plate


62


is moved upwardly, the corresponding sloping surface


62




a


and recess floor


64




a


force the tooling plate


20


to move perpendicularly away from the front face


18




a


of the beam. As this occurs, guiding assemblies


40


prevent tooling plate


20


from moving further away, and the rear surface of wedge plate


62


pressing against the front surface


18




a


of tooling plate


20


secures the movable support structure


14


to the I-beam support member


18


. The orientation of wedge plate


62


and pocket


64


are selected so that an increase in downward force upon tooling plate


20


will also cause wedge plate


62


to bear more firmly against surface


18




a


of I-beam


18


, thereby increasing the frictional force constraining tooling plate


20


. In other words, wedge assembly


60


is constructed and arranged such that any further downward motion of tooling plate


20


(parallel to the longitudinal axis of the I-beam


18


) applies even more force to wedge plate


62


against the beam


18


. Therefore, the more force that is applied to the tooling plate


20


substantially along the longitudinal axis of I-beam


18


, either due to the weight of the workpiece


26


or the force of the tooling


24


, then the tighter wedge plate


62


will lock against front surface


18




a


of the I-beam


18


. Wedge assembly


60


is thereby self-tightening.




Wedge assembly


60


also includes a release lever


70


having its center portion clamped to the front face


20




a


of tooling plate


20


. In the preferred embodiment, release lever


70


is constructed of ⅜-inch diameter hot rolled steel bar stock. As shown in

FIG. 8

, the center portion of release lever


70


includes a tab or tongue


72


that engages a slot


74


in wedge plate


62


, since tooling plate


20


has a cutout


76


through which tongue


72


is projected through pocket


64


into to wedge plate


62


. In the preferred embodiment, one end of release lever


70


is offset to one side of tooling plate


20


and formed as a handle


78


.




When the operator lifts handle


78


of release lever


70


upwardly, tongue


72


and wedge plate


62


are forced downwardly, thereby disengaging rear surface


62




b


from beam surface


18




a


in preparation for repositioning tooling plate


20


to a new height. After the wedging action has been released, tooling plate


20


can be raised or lowered to any point along the center-working portion of the I-beam


18


. Similarly, if tooling plate


20


itself is raised, wedge plate


62


moves downwardly relative to tooling plate


20


and the wedging action is also removed.




Conversely, if the operator presses downwardly on handle


78


of release lever


70


, tongue


72


and wedge plate


62


are forced upwardly, thereby engaging first sloping surface


62




a


with recess floor


64




a


to tightly engage wedge plate


62


against front surface


18




a


of I-beam


18


. Once wedge plate


62


is raised into place, any downward motion of tooling plate


20


will further force rear surface


62




b


against beam surface


18




a


and prevent any further motion of tooling plate


20


. Hence, the force of gravity on movable support structure


14


and/or the force applied by tooling


24


against worktable


22


(if they are not affixed to the same tooling plate


20


) will serve to further increase the securing force directly against the surface of I-beam


18


and further decrease the ability of the movable support structure


14


to slip.




Note that the coefficient of static friction of wedge plate


62


upon I-beam


18


, and, similarly, the force securing the position of tooling plate


20


, can be increased by texturing either the rear surface


62




b


of wedge plate


62


or the front surface


18




a


of I-beam


18


. In the preferred embodiment, the rear surface of wedge plate


62


includes transverse serrations or diamond knurling or some other texturing, such that no additional machining has to be done to I-beam


18


.




Also note that one of the principal aspects of the present invention is the correspondence of sloping surface


62




a


and


64




a


. Note that if corresponding sloping surfaces were not used, then any downward force on tooling plate


20


would just try to pry the bottom portion of tooling plate


20


away from beam


18


, acting unevenly against only two guiding assemblies


40


. Furthermore, the downward force of tooling plate


20


would not be translated by 90 degrees to be applied evenly as a normal force against the I-beam surface


18




a


or distributed evenly across the rear surface


62




b


of the wedge plate


62


. Although this uneven application of forces may work in some light-duty applications, it is preferable that the force provided by the wedge plate


62


be applied approximately normal to the face of the I-beam, i.e., 90 degrees to the longitudinal axis of support member


18


.




One skilled in the art may further note that the use of a recess or pocket


64


in the back surface of the tooling plate


20


is not the only way to form a second sloping surface. It should be understood that an additional wedge plate may be affixed to the rear surface


20




b


of the tooling plate


20


to provide the second sloping surface. Moreover, a simple angled cut-off of the lower edge of the tooling plate


20


could alternatively be used, and perhaps be the most economical approach. In the preferred embodiment, the sloping surface is at an angle of approximately 4 degrees from the longitudinal axis of the I-beam


18


. However, it is contemplated that any angle within the range of 2 degrees to 30 degrees would also serve the function of efficiently translating the downward forces applied to the tooling plate into inward forces applied against the I-beam. In the preferred embodiment, angles of 10 degrees or less are favored.




The use of recess or pocket


64


, however, provides an additional advantage in the preferred embodiment. The use of pocket


64


also serves to enclose wedge plate


62


such that it remains in the correct position and orientation between the tooling plate


20


and the I-beam


18


at all times, whether or not the tongue


72


of lever arm


70


are designed to serve this purpose. In the preferred embodiment, pocket


64


also holds wedge plate


62


during assembly of the wedge assembly


60


. However, if a pocket is not used, wedge plate


62


can be held in place with a flexible cord or spring or equivalent.




Movable support structure


14


is typically too heavy to be repositioned manually by the operator. This would most certainly be the case with worktable


22


, tooling


24


, and safety guard structure


28


installed on tooling plate


20


. Therefore, several mechanisms have been provided to raise and lower movable support structure


14


. These mechanisms may also be used to replace the tooling plate


20


with another tooling plate for a different operation at the same workstation.




In the preferred embodiment, tooling plate


20


includes one or two lifting eyes, shown in FIG.


3


and

FIG. 4

as shackles


80


. These shackles would be attached to a shop crane, or block and tackle, or other overhead lifting apparatus to raise and lower the backbone assembly. Tooling plate


20


may also be provided with lifting pockets (not shown) to facilitate engagement of a lift truck to provide for raising or lowering tooling plate


20


to a new position.




If the tooling or worktable height is to be adjusted more frequently, such as the situation where there is a large amount of human operator intervention required at a particular workstation, an alternative lifting apparatus can be used. As shown in

FIGS. 3 and 4

, a hydraulic or air cylinder assembly


82


, having a cylinder


84


and a rod


86


powered by an external hydraulic or air powered unit (not shown), is provided under tooling plate


20


for adjusting the height of the movable support structure


14


. Alternatively, any other type of jack apparatus, even an automobile jack, could be used.




Accordingly, after the height of tooling plate


20


is adjusted using cylinder assembly


82


, the operator would push handle


78


downward to engage wedge plate


62


. The operator would then release the force from cylinder assembly


82


, whereupon gravity acting on the movable support structure


14


would cause the complementary sloping surfaces of the wedging assembly


60


to force rear surface


62




b


of wedge plate


62


tighter against the surface


18




a


of the I-beam


18


. This action locks tooling plate


20


into the desired new position. As mentioned above, any additional downward forces, caused either by the weight of workpiece


26


resting on worktable


22


, or by the forces applied by separately mounted tooling


24


against workpiece


26


, would cause wedge plate


62


to grip tighter. Hence, even though the movable support structure


14


is adjustable to an infinite number of positions within the I-beam adjustment range, the present invention provides a locking function that is extremely strong. In the preferred embodiment, the wedge assembly


60


can support a load of over 1000 pounds without slipping.




The present invention may be used in a variety of other tooling and assembly cell configurations. In particular, support member


18


does not have to be vertical as in the preferred embodiments. It is contemplated that the same wedge assembly


60


could be used with a horizontal beam orientation for use with horizontal milling or drilling machining applications. Although the vertical force of gravity will not be assisting to increase the wedging and locking forces in a horizontal orientation, the horizontal force applied by the tooling against the workpiece would serve to do so.




The dimensions of the workstation of the preferred embodiment are as follows:




Base


16


: 964 mm wide by 900 mm deep by 362 mm high;




Support member


18


: 250 mm wide by 265 mm deep by 2000 mm high;




Tooling plate


20


: 395 mm wide by 1225 mm tall by 48 mm thick;




Worktable


22


: 390 mm wide by 305 deep by 25 mm thick;




Safety guard structure


28


: 1000 mm wide by 1100 mm tall by 700 mm deep;




Worktable support bracket


42


: 250 mm deep by 155 mm high by 25 mm thick with 45 degree angle from the far edge;




Bearing plate


52


: 148 mm tall by 76 mm wide by 6.4 mm thick;




Wedge plate


62


: 76 mm wide by 95 tall by 21 mm thick at bottom (thickest) tapering at 4 degrees to 14 mm thick at top (thinnest) and having a tongue slot of 36 mm wide by 17 mm high, and having 6 mm by 6 mm wide by 3 mm tall cross-hatched points on the rear surface.




Lever arm


70


: 425 mm long (central part) with 200 mm arm with 65 mm handle made of 10 mm diameter rod;




Lever arm tongue


72


: 46 mm long by 28 wide by 10 mm thick;




Tooling plate pocket


64


: 90 mm wide by 125 mm tall by 22 mm deep at bottom of wedge (deepest) sloping at 4 degrees to top of the wedge (shallowest);




Tooling plate cutout


76


: 64 mm wide by 75 mm tall;




Hydraulic cylinder assembly


82


: 400 mm high when at the bottom of stroke, and add 305 mm when at the top of stroke.




While specific embodiments of the present invention have been shown and described herein, further modifications and improvements may be made by those skilled in the art. In particular, it should be noted that more than one tooling plate assembly could be used on the same beam to hold both the tooling and the workpiece. Moreover, a tooling plate


20


may be placed on both the front and rear sides of a single beam. Support member


18


may also be disposed horizontally upon or above a floor, and wedge assembly


60


used to secure position against a load force not related to weight. Numerous modifications may also be made to customize the present invention for various other applications. All such modifications, which retain the basic underlying principles disclosed and claimed herein, are within the scope and spirit of the invention.



Claims
  • 1. An adjustable workstation, comprising:a fixed support structure; a movable support structure movably engaged with the fixed support structure, the movable support structure including a rear portion facing the fixed support structure and a front portion substantially opposite the rear portion; a first wedge surface coupled to the rear portion of the movable support structure and having a slope relative to the fixed support structure; a second wedge surface located between the first wedge surface and the support structure, the second wedge surface cooperating with and complementary to the first wedge surface, wherein a force in a first direction on the second wedge surface relative to the first wedge surface results in a constrainment of the movable support structure relative to the fixed support structure, and wherein a force in a second direction substantially opposite the first direction on the second wedge surface relative to the first wedge surface results in a release of constrainment of the movable support structure relative to the fixed support structure.
  • 2. The adjustable workstation of claim 1, wherein the second wedge surface is located on a first wedge plate between the tooling system and the support system.
  • 3. The adjustable workstation of claim 2, wherein the first wedge surface is located on the rear portion of the tooling system.
  • 4. The adjustable workstation of claim 3, wherein the rear portion of the tooling system comprises a second wedge plate fixedly attached to the front portion of the tooling system.
  • 5. The adjustable workstation of claim 3, wherein the tooling system includes a recess in the rear portion thereof, the rear portion including the first wedge surface for interaction with the second wedge surface.
  • 6. The adjustable workstation of claim 2, further comprising a lever having first and second ends, the lever coupled to the second wedge surface at the second end thereof such that a force on the first end of the lever results in a substantially opposite force on the second wedge surface.
  • 7. The adjustable workstation of claim 2, further comprising a worktable coupled to the tooling system.
  • 8. The adjustable workstation of claim 2, further comprising a tool for interacting with a workpiece, the tool coupled to the tooling system.
  • 9. The adjustable workstation of claim 2, further comprising a guard structure coupled to the tooling system.
  • 10. The adjustable workstation of claim 2, further comprising a plurality of guiding assemblies coupled to the tooling system, the guiding assemblies cooperating with a plurality of inner edges of the support system to slidably engage the tooling system with the support system.
  • 11. The adjustable workstation of claim 2, further comprising means for altering the position of the tooling system relative to the support system.
  • 12. An adjustable workstation, comprising:a base; a support member coupled to the base; a tooling plate having a rear surface facing the support member and a front surface substantially opposite the rear surface, the tooling plate including a recess disposed within the rear surface thereof, the recess defining a sloped surface relative to the rear surface, the tooling plate slidably engaged with the support member; and a wedge plate disposed within the recess and having a sloped surface complementary to the sloped surface of the recess, wherein a movement of the wedge plate in a first direction relative to the recess results in the sloped surfaces of the recess and the wedge plate cooperating to inhibit movement of the tooling plate relative to the support member and wherein a movement of the wedge plate in a second direction substantially opposite the first direction relative to the recess results in the sloped surfaces of the recess and the wedge plate cooperating to uninhibit movement of the tooling plate relative to the support member.
  • 13. The adjustable workstation of claim 12, further comprising a lever arm having a free end and a fixed end coupled to the wedge plate, wherein a movement of the free end in a third direction results in a movement of the wedge plate in a fourth direction substantially opposite the third direction.
  • 14. The adjustable workstation of claim 13, further comprising a tool coupled to the tooling plate.
  • 15. The adjustable workstation of claim 14, further comprising a worktable coupled to the tooling plate.
  • 16. The adjustable workstation of claim 13, further comprising a hydraulic assembly coupled to the tooling plate, the hydraulic assembly selectively repositioning the tooling plate relative to the support member.
  • 17. The adjustable workstation of claim 13, further comprising an air cylinder assembly coupled to the tooling plate, the air cylinder assembly selectively repositioning the tooling plate relative to the support member.
  • 18. The adjustable workstation of claim 13, further comprising a guard frame coupled to the tooling plate.
  • 19. The adjustable workstation of claim 13, further comprising a plurality of guiding assemblies coupled to the tooling plate, the guiding assemblies cooperating with a plurality of inner edges of the support member to slidably engage the tooling plate with the support member.
  • 20. The adjustable workstation of claim 13, further comprising a jack assembly coupled to the tooling plate, the jack assembly selectively repositioning the tooling system relative to the support member.
Parent Case Info

This application claims priority of U.S. Serial No. 60/200,788, filed April 28, 2000.

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Provisional Applications (1)
Number Date Country
60/200788 Apr 2000 US