Ergonomically adjustable machine operator platform

Information

  • Patent Grant
  • 6253878
  • Patent Number
    6,253,878
  • Date Filed
    Tuesday, August 17, 1999
    25 years ago
  • Date Issued
    Tuesday, July 3, 2001
    23 years ago
  • Inventors
  • Examiners
    • Kramer; Dean J.
    • Chin; Paul T.
    Agents
    • Graham; R. William
Abstract
An ergonomically adjustable machine operator platform includes a worker support surface which includes a top surface and a bottom, a plurality of support legs disposed on a floor, wherein each support leg includes an external threaded surface portion, a drive member operably connected to each support leg and having an inner threaded bored surface therethrough which is configured to be complimentary threaded to the external threaded surface portion in a manner to permit axial movement along the support leg and wherein the drive member includes a bearing support surface disposed adjacent the bottom. The drive member further includes an exterior sprocket surface extending generally radially from the drive member, and a rotating device connected to the external sprocket surface for rotating the drive member to cause axial movement along the support leg to vertically move the worker support surface.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The invention relates to platforms used to elevate a machine operator. More particularly, the invention is directed to improvements in adjustable machine operator platforms.




2. Related Art




Assembly line work typically requires a worker to standing at a station for an extended period of time to perform a manual task. The machinery is typically fixed at a predetermined height. If the operator is taller or smaller than average, the operator cannot comfortably work at the station. The operator must bend, extend or reach to do the work which causes the operator to prematurely fatigue. Therefore, the operator's height must be taken into consideration in achieving maximum work productivity. Accordingly, there is a need to accommodate the height of the machine operator. Platforms have been made to accommodate the machine operator's height.




For example, there exist platforms which are height adjustable to aid the machine operator in comfortably performing the job. Height adjustable work platforms maximize the operator's effectiveness by positioning the operator at a height which permits easier access to work areas. These platforms have aided by preventing muscle strain and fatigue.




While the advent of adjustable platforms have been an improvement over traditional fixed work platforms, they have had problems in their implementation into the work environment. For example, present height adjustable platforms frequently fail due to the environment in which they are used. Debris, such as metal shavings have a tendency to become caught in the moving parts and cause seizure. Hydraulic systems employed are relatively expensive and also are less reliable than desired.




Thus, a more suitable height adjustable platform is desired which is readily movable to a desired location and able to withstand rigorous environments while maintaining user friendly characteristics. Also, a platform structure which is relatively low cost, easy to manufacture and use is desirable. The present invention aims at meeting these desires.




BRIEF SUMMARY OF THE INVENTION




It is an object to improve work conditions in an assembly or work line environment.




It is another object to improve height adjustable platforms.




It is another object to improve the lifting mechanisms in height adjustable platforms.




Another object is to provide a platform which is electro-mechanically height adjustable to a desired height.




Still another object of the present invention is to provide a platform which is relatively low cost, user friendly, mobile and rugged.




Accordingly, the present invention is directed to an ergonomically adjustable machine operator platform, which includes:




a worker support surface which includes a top surface and a bottom;




a plurality of support legs disposed on a floor, wherein each said support leg includes an external threaded surface portion;




a drive member operably connected to each support leg and having an inner threaded bored surface therethrough which is configured to be complimentary threaded to the external threaded surface portion in a manner to permit axial movement along the support leg and wherein the drive member includes a bearing support surface disposed adjacent the bottom, the drive member further includes an exterior sprocket surface extending generally radially from said drive member; and




means connected to the external sprocket surface for rotating the drive member to cause axial movement along the support leg to vertically move the worker support surface.




Other objects and features of the invention advantage which will become apparent from reading the following and are set forth in more detail in the description and accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of an ergonomically adjustable machine operator platform in accordance with the present invention.





FIG. 2

is another perspective view of an ergonomically adjustable machine operator platform in

FIG. 1

, shown with the worker support surface removed.





FIG. 3

is another perspective view of an ergonomically adjustable machine operator platform in

FIG. 1

, shown with the worker support surface removed.





FIG. 4

is a bottom view of the ergonomically adjustable machine operator platform of FIG.


1


.





FIG. 5

is a cross-sectional view of a support leg used in the present invention.





FIG. 6

depicts a travel switch assembly used in the present invention.











DETAILED DESCRIPTION OF THE INVENTION




Referring now to the drawings which are illustrated in the accompanying Figures, an ergonomically adjustable machine operator platform of the present invention is generally identified by the numeral


10


. The platform


10


is commonly used with a machine (not shown) wherein the machine operator is required to be disposed at a certain height in order to operate the machine. The platform


10


is preferably portable and moved a desired site.




The platform


10


includes a support frame


12


, a worker support surface


14


connected to the support frame


12


, a plurality of support legs


16


, and drive chain assembly


18


, drive motor/shaft member


20


, power source housing


22


operably interconnecting to each support leg


16


and railing


24




a


and


24




b


connected to the support frame


12


. A portable step


26


is also provided which is disposed adjacent the platform


10


such that when the platform


10


is in the low position, the machine operator can easily step up on the worker support surface


14


.




More specifically in

FIGS. 2 and 3

, the support frame


12


includes four side beams


13




a


,


13




b


,


13




c


and


13




d


which are fixably interconnected to one another at their ends. Cross beams


15




a


and


15




b


fixably interconnect side beams


13




b


and


13




d


and aid in supporting the worker support surface


14


. The support frame


12


is of a rigid construction material, such as steel, as is the worker support surface


14


.




The railing


24




a


and


24




b


are of a type known in the art, such as tubular steel, and removably connect to the side beams


13




a


and


13




c


, respectively. Removable mounts


19




a


and


19




b


, and


19




c


and


19




d


connect to side beams


13




a


and


13




c


, respectively, to the railings


24




a


and


24




b


, respectively.




Turning to

FIGS. 5 and 2

, the support legs


16


and their connection and operation with the support frame


12


are as follows. For brevity, one support leg


16


connection will be discussed as the support legs


16


are identical and interconnections similar for all side beams


13




a


,


13




b




13




c


and


13




d.






Accordingly, a generally rectangular top plate


30


is fixably connected to an inside corner surface


31


formed by the connection of the ends of side beams


13




b


and


13




c


. The top plate


30


includes a generally cylindrical central inner open surface


32


extending axially therethrough. A generally cylindrical bushing


33


has an outer diameter to fit within the open surface


32


and inner open surface


35


therethrough. Another inner open threaded surface


34


extends from an outer surface of the top plate


30


radially inward through the top plate


30


and the bushing


33


to the open surface


35


formed within the bushing


33


.




The support leg


16


includes a rigid generally cylindrical threaded screw


36


having an outer diameter slightly less than an inner diameter of open surface


35


to permit relatively unrestricted movement therebetween. The threaded screw


36


includes a keyway


38


which longitudinally extends a predetermined length along the threaded screw


36


. A threaded anti-rotation screw


40


is threaded to the threaded inner open surface


34


and has an end stop


42


of a size and configuration to be slidably received within the keyway


38


. When the screw


40


is threaded to the top plate


30


, the end stop


42


limits the travel of the top plate


30


to the approximate length of the keyway


38


. Also, a bottom end


44


of the threaded screw


36


includes a generally axially inwardly extending threaded open surface


46


which is generally centrally positioned.




A foot


48


having an upwardly extending collar


49


is disposed on a floor. The foot


48


includes a threaded open surface


50


which extends generally axially inwardly through the collar


49


and is generally centrally positioned having a diameter substantially that of open surface


46


. A threaded connecting screw


52


threadably interconnects the screw


36


and foot


48


via threaded open surfaces


46


and


50


, respectively, such that the end


44


sits on the foot


48


.




Below the top plate


30


is a thrust bearing assembly


54


having a central open surface


56


of a diameter larger than the diameter of a collar


58


of a combination spacer and thrust bearing locator


60


. The locator


60


includes a generally centrally located open surface


64


which axially extends therethrough and has a diameter slightly larger then the screw


36


to permit relatively unrestricted movement along the screw


36


.




A nut


66


includes a threaded inner surface


68


which is of a diameter and complimentary configuration to threadably receive the threaded screw


36


. A sprocket


70


radially extends from the nut


66


. The sprocket


70


is fixed to the nut


66


such that as the sprocket


70


is turned so turns the nut


66


causing the nut


66


to move axially up or down along the screw


36


depending upon the direction the sprocket


70


is turned.




A generally cylindrical spacer bearing


72


is provided about the screw


36


and has an open surface


74


generally centrally extending therethrough. The spacer bearing


72


is disposed below the nut


66


and sprocket


70


in a manner to permit relatively unrestricted movement along the screw


36


.




A bottom plate


76


having a collar


78


includes a generally centrally located open surface


80


which axially extends therethrough larger than the diameter of the screw


36


. A generally cylindrical bushing


82


is disposed between the threaded screw


36


and the open surface


80


and similarly has an inner open surface


84


of a diameter slightly larger then the screw


36


to permit relatively unrestricted movement along the screw


36


. The collar


78


is disposed downward towards the foot


48


.




A protective expandable bellows


86


is disposed about the threaded screw


36


in a spaced relation thereto. The ends


88


and


90


of the bellows


86


connect to collars


78


and


49


, respectively. The bellows


86


protects the screw


36


from debris, such as metal shavings or the like, which can cause the nut


66


to bind with the screw


36


. The bellows


86


is accordion like and can expand and contract with the aforesaid parts as they move axially up and down the screw


36


. The bellows


86


is thus preferably of an elastic nature, such as neoprene rubber.




Similarly, a top cover


92


is disposed about the threaded screw


36


in a spaced relation thereto above the top plate


30


. A top end


94


is closed and bottom end


96


is open and interconnects to the top plate


30


via a collar clamp


98


which mounts to the top plate


30


.




Power source housing


22


includes power source connections and is operably connected in a suspended manner from the cross beam


15




b


. The drive member


22


operably connects to drive motor/shaft member


20


which includes a drive motor


100


and drive motor speed reducer and drive shaft


102


.




The drive shaft


102


is operably connected to drive member


18


via a roller drive chain


104


. As seen in

FIG. 6

, the drive chain assembly


18


further includes a travel switch assembly


106


having an up end travel switch


108


and a down end travel switch


110


, both of which are operatively connected to the drive member


22


to cause power to cease to drive member


20


when switch contact


112


contacts either switch contact arm


114


or


116


and limit directional travel of said roller drive chain


104


. This prevents run-out of the anti-rotation screw


40


through the keyway


38


as seen in FIG.


5


. This, together with the end stop


42


limits, the vertical movement of the worker support surface


14


(

FIG. 1

) is limited and provides a safety stop mechanism.




The roller drive chain


104


is operatively connected to each of the sprockets


70


. As the sprockets


70


turn, the nut


66


is controllably driven axially along the length of the screw


36


. This in turn indirectly causes the platform to go up and down. An operator controller


120


is connected to the support railing


24




a


and operatively connected to the drive member


22


.




The platform


10


may be readily used by workers of different heights to enhance the work environment and productivity of the workers without having to change the machinery set up. The present invention further provides a platform which is more reliable and relatively inexpensive. The platform


10


is also provided to endure rigorous machine operating environments.




The above described embodiments is set forth by way of example and is not for the purpose of limiting the present invention. It will be readily apparent to those skilled in the art that obvious modifications, derivations and variations can be made to the embodiment without departing from the scope of the invention. Accordingly, the claims appended hereto should be read in their full scope including any such modifications, derivations and variations.



Claims
  • 1. An ergonomically adjustable machine operator platform, which includes:a worker support surface which includes a top surface and a bottom; a plurality of support legs on a floor, wherein each of said support legs includes an external threaded surface portion and wherein at least one of said support legs includes a longitudinally axially extending keyway in said external threaded surface portion, and further includes a stop operably associated with said worker support surface which permits longitudinal axial travel within said keyway between a first and second position to limit vertical movement of said worker support surface and wherein said stop prevents rotational movement of said support leg; a drive member operably connected to each support leg and having an inner threaded bored surface therethrough which is configured to be complimentary threaded to said external threaded surface portion in a manner to permit axial movement along said support leg, and wherein said drive member is disposed in a bearing manner adjacent to said bottom of said worker support surface and wherein said drive member further includes a threaded nut having an exterior sprocket surface attached thereto, said sprocket surface extending generally radially from said drive member; means connected to said external sprocket surface said means including a roller drive chain operably connected to said sprocket surface and a rotatable drive shaft connected to said roller drive chain and a drive motor for rotating said drive member to cause axial movement along said support leg to vertically move said worker support surface; and a travel switch connected to said roller chain drive to limit vertical travel of said worker support surface.
  • 2. The platform of claim 1, which includes means for stopping said rotating means such that said worker support surface can be disposed at predetermined axial positions along said support leg.
  • 3. The platform of claim 1, which includes means connected to said support leg for covering said external threaded surface portion as said drive member threadably moves along axially along said support leg.
  • 4. The platform of claim 3, wherein said covering means includes a top cover extending over said support leg in a spaced relation thereto above said drive member and operably connected to the top surface of said worker support surface and an expandable bellows cover which axially extends about said support leg below said drive member in a spaced relation thereto, wherein said top cover and said bellows cover cooperate in a manner to substantially cover said support leg as said drive member moves axially along said support leg.
  • 5. The platform of claim 1, which further includes a controller connected to said rotating means for controlling the amount of rotation of said drive member and axial position of said worker support surface and height thereof.
  • 6. The platform of claim 1, which further includes controller means for controlling the travel of said roller drive chain.
  • 7. The platform of claim 1, which further includes a roller thrust bearing disposed between said drive member and said bottom of said worker support surface.
  • 8. The platform of claim 7, which further includes a spacer disposed between said roller thrust bearing and said drive member.
  • 9. An ergonomically adjustable machine operator platform, which includes:a worker support surface which includes a top surface and a bottom; a plurality of support legs on a floor, wherein each of said support legs includes an external threaded surface portion wherein at least one support leg includes a longitudinal axially extending keyway therein, and further includes a stop operably associated with said worker support surface which permits longitudinal axial travel within said keyway between a first and second position to limit vertical longitudinal axial travel within said keyway between a first and second position to limit vertical movement of said worker support surface and wherein said stop prevents rotational movement of said support leg, a drive member operably connected to each support leg and having an inner threaded bored surface therethrough which is configured to be complementary threaded to said external threaded surface portion in a manner to permit axial movement along said support leg, and wherein said drive member includes a threaded nut having an exterior sprocket surface attached thereto and extending generally radially from said drive member; means operably connected to said external sprocket surface said means including a roller drive chain operably connected to said sprocket surface and a rotational drive shaft connected to said roller drive chain and a drive motor for rotating said drive member to cause axial movement along said support leg to vertically move said worker support surface; a roller thrust bearing disposed between said drive member and said bottom of said worker support surface, which further includes a spacer disposed between said roller thrust bearing and said drive member; and a travel switch connected to said roller drive chain to limit vertical travel of said worker support surface.
  • 10. The platform of claim 9, which further includes a controller connected to said rotating means for controlling the amount of rotation of said drive member and axial position of said worker support surface and height thereof.
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