Abstract:
The invention is a device, such as a chute or a conveyor belt, for receiving and transferring work pieces in a factory, mounted on a set of legs with lockable wheels at the bottom of each leg. Each leg is equipped with an hydraulic extension unit that is operated by air pressure. The air pressure is provided, for instance, from a machine, such as a press, that performs work on the work piece. Each leg is individually adjustable by the pneumatic extension unit, allowing the device atop the legs to be adjusted in height from the support surface, and maintained level or tilted from side to side or front to back. The wheels on the leg bottoms allow the device supported on the legs to easily move from one location to another on the factory floor. The legs may optionally be designed to fold up against the bottom of the supported device for ease of storage of the device. 
     The advantages of the height and level adjustable features of the work surface device include allowing workers of various stature to safely and comfortably handle work pieces. A single device can be height and level adjusted for each worker that uses the device.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit under 35 U.S.C. §119(e) of co-pending provisional application Ser. No. 60/088,552, filed Jun. 9, 1998. Application Ser. No. 60/088,552 is herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a device for adjusting both the height and side to side orientation of a work surface or similar piece of equipment relative to the support surface on which the device is located. 
     BACKGROUND OF THE INVENTION 
     In the modern manufacturing workplace, individual workers are often required to perform repetitive tasks while positioned at a specific location. The worker may have a particular work surface at which to perform the repetitive task. The manufacturing facilities often operate continuously with one or more worker at each work station during each shift of operation. A particular work station work surface may not be suited to the stature of all works who perform tasks at that station. When performing repetitive tasks, such as handling heavy work pieces, the worker may experience physical discomfort or injury when the work surface is not matched to the stature of that worker. Providing a customized work surface for each worker at a work station is economically prohibitive. Thus, there is an unmet need for a device which can be individually adjusted for the needs of each worker who performs tasks at a particular work station work surface. 
     A number of patents concerned with devices that can adjust the height of a work surface or similar structure have been granted. 
     Feiertag, in U.S. Pat. No. 3,820,176, discloses a patient handling table that employs a combination of a hydraulic cylinder and cable with pulleys to raise, lower and tilt the table to from end to end. 
     Hinman, in U.S. Pat. No. 3,827,663, shows a spring loaded, self adjusting furniture support to accommodate uneven surfaces. 
     Dufrancatel, in U.S. Pat. No. 4,396,222, discloses a trailer with adjustable interior components. 
     In U.S. Pat. No. 4,441,432, Carlton shows a tilting table top with pins mounted in horizontal slots and in angled slots with notches to allow tilting of the table top. 
     Vertically adjustable tables are disclosed by de la Haye in U.S. Pat. No. 4,615,279 and by Peterson et al in U.S. Pat. No. 4,828,208. Both patents describe mechanical gearing to adjust a table top surface. 
     In U.S. Pat. No. 4,944,366, Pryor et al. disclose a pneumatic operated scaffolding to lift sheet rock for ceiling joist attachment. The scaffolding contains four legs with pneumatic cylinders for raising a work support frame. The pneumatic cylinders are removable from the support frame for transport. 
     U.S. Pat. No. 5,531,413 by Wolf et al. discloses a pneumatic or hydropneumatic length adjusting cylinder for chairs, tables and the like, designed to prevent twisting. 
     Jonker, in U.S. Pat. No. 5,598,788, describes an adjustable height table with two leg supports. Each leg has a gas spring that resists movement and a ratcheting latch mechanism to maintain a selected table height. 
     In U.S. Pat. No. 5,615,451, Peterson et al. describe a roller assembly that pivots between up and down positions to elevate or lower an attached table. The roller assembly allows the table to be rolled between locations and set in position with the roller assembly retracted. 
     In U.S. Pat. No. 5,161,868, Hooser discloses a telephone table with locking casters and means for elevating the table top. The elevating means may be four electrical stepping motors, each of which rotate a threaded shaft in one leg, or a central hydraulic lift cylinder with four hydraulic power cylinders for tilting the table top. The hydraulic system requires an electrical pump to power the system. The stepping motors are controlled in pairs to allow the table top to be tilted from front to back. 
     Zeiner, in U.S. Pat. No. 5,437,236, describes a rectangular table with a similar base support. A central cylindrical support is fitted with an air pump to cause the cylinder to elevate the table top. Two to four telescoping legs, each with set screws, are positioned to support the table top. 
     SUMMARY OF THE INVENTION 
     The invention is an elevational and tilt adjustable work surface device comprising a generally planar work surface member with top and bottom surfaces. A plurality of height adjusting leg members are secured to the bottom surface of the work surface member. The height adjusting leg member comprise a bracket member secured to the work surface member bottom side, with a telescoping support member oriented generally perpendicular to the work surface member and fastened at a first support member end to the bracket member. The telescoping support member is preferably a gas shock cylinder member, connected to a supply means for delivery of compressed gas thereto. A rigid leg member is attached to the telescoping support member second end opposite the bracket member. Individual control means for admitting gas to or releasing gas from the gas supply means connected to the individual gas shock cylinder members is secured to the work surface device, whereby each height adjusting leg member is independently height adjustable by the individual control means, thereby providing an elevational and tilt adjustable work surface member. 
     The work surface member may be as simple as a chute to collect and store work pieces or transfer work pieces from one location to another. Alternatively, the work surface member may be relatively complex, such as a conveyor belt with associated power motor, where the belt moves by means of the motor to transport work pieces from point to point. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Reference is next made to a brief description of the drawings, which are intended to illustrate the preferred embodiment of the present invention with respect to the manner of making and using the same in its presently understood best mode. The drawings and the detailed description which follow are intended to be merely illustrative and not otherwise limiting of the scope of the invention as set forth in the appended claims. 
     FIG. 1 is a side plan view of the adjustable work surface device of the present invention. 
     FIG. 2 is an end view of the adjustable work surface device. 
     FIG. 3 is a side plan view of the device with one end of the work surface elevated. 
     FIG. 4 is an end view of the device with the work surface tilted to one side. 
     FIG. 5 is a side plan view of the upper portion of the height adjusting leg member. 
     FIG. 6 is a side plan view of the lower portion of the height adjusting leg member. 
     FIG. 7 is a side plan view of the pneumatic control device of the present invention. 
     FIG. 8 is a cross sectional view of the pneumatic control device along line C—C of FIG.  7 . 
     FIG. 9 is a side plan view of the adjustable work surface device connected to a compressed gas supply source. 
     FIG. 10 is a side plan view of a conveyor system mounted on the work surface device. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Nomenclature 
     
       
         
               
               
             
               
               
             
           
               
                   
               
               
                 S 
                 Support Surface 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 10 
                 Adjustable Work Surface Device 
               
               
                 20 
                 Planar Rectangular Work Surface Member 
               
               
                 22 
                 Top Side of Work Surface Member 
               
               
                 24 
                 Bottom Side of Work Surface Member 
               
               
                 30 
                 Height Adjusting Leg Member 
               
               
                 31 
                 Bracing Members 
               
               
                 32 
                 Bracket Member 
               
               
                 34 
                 Circular Fastener Members 
               
               
                 36 
                 Aperture in Circular Fastener Member 
               
               
                 38 
                 Retaining Rod Member 
               
               
                 40 
                 Hollow Cylindrical Collar Member 
               
               
                 42 
                 Fastening Screw Member 
               
               
                 44 
                 Tie Rod Member 
               
               
                 46 
                 Hollow Cylindrical Rubber Bushing Member 
               
               
                 50 
                 Telescoping Support Member 
               
               
                 51 
                 Expandable Dust Boot Member 
               
               
                 52 
                 Rigid Leg Member 
               
               
                 54 
                 Lockable Pivot Member 
               
               
                 56 
                 Top Portion of Pivot Member 
               
               
                 58 
                 Leg Sections of Pivot Member 
               
               
                 60 
                 Pivot Pin Member 
               
               
                 62 
                 Leg Stop Member 
               
               
                 64 
                 Locking Pin Member 
               
               
                 66 
                 Lockable Wheeled Castor Member 
               
               
                 68 
                 Fork Lift Bracket Member 
               
               
                 70 
                 Compressed Gas Conduit Member for Individual Gas Shock 
               
               
                   
                 Cylinder 
               
               
                 72 
                 Pneumatic Control Device 
               
               
                 74 
                 Bracket Holder for Pneumatic Control 
               
               
                 78 
                 Control Switch Members 
               
               
                 80 
                 Gas Manifold Channel 
               
               
                 81 
                 Body Member of Pneumatic Control Device 
               
               
                 82 
                 Gas Inlet Connector Member 
               
               
                 84 
                 Gas Inlet Tank Valve Member 
               
               
                 86 
                 Gas Supply Channel 
               
               
                 88 
                 Coupler Plug Member 
               
               
                 90 
                 Gas Outlet Channel 
               
               
                 92 
                 Compressed Gas Source 
               
               
                 94 
                 Main Gas Supply Conduit Member 
               
               
                 96 
                 Compressed Gas Cylinder 
               
               
                 100 
                 Machine Control Device 
               
               
                 102 
                 Control Conduit Line Member for Machine 
               
               
                 104 
                 Bracket Member for Machine Control Device 
               
               
                 106 
                 Lock Pin Member of Bracket Member 
               
               
                 120 
                 Chute Device 
               
               
                 122 
                 Horizontal Bottom Work Surface of Chute 
               
               
                 124 
                 Vertical Side Members of Chute 
               
               
                 126 
                 Vertical End Members of Chute 
               
               
                 128 
                 Extension Surface Member 
               
               
                 150 
                 Conveyor Belt Device 
               
               
                 152 
                 Roller Members of Conveyor 
               
               
                 154 
                 Continuous Belt Member of Conveyor 
               
               
                 156 
                 Motor Member for Driving Conveyor Device 
               
               
                 158 
                 Switch Member for Motor 
               
               
                   
               
             
          
         
       
     
     Construction 
     Referring to FIGS. 1-4, the elevational and tilt adjustable work surface device  10  of the present invention is shown. The device  10  includes a generally planar and rectangular work surface member  20  with a top side  22  and a bottom side  24 . The work surface member  20  is depicted as a simple container for purposes of explanation, although a variety of work surface members capable of multiple functions are contemplated. These embodiments will be described in detail later. 
     The planar rectangular work surface member  20  is oriented parallel to a supporting surface S, such as a floor in a manufacturing facility. The planar rectangular work surface member  20  is supported by a plurality of height adjusting leg members  30  secured to the bottom side  24  of the planar rectangular work surface member  20 . A minimum of three leg members  30  are required to suppor the work surface member  20 . Preferably at least four leg members  30  are secured to the planar rectangular work surface member  20  with the leg members  30  positioned roughly at the corners thereof. The leg member  30  are also maintained perpendicular to the work surface bottom side  24  by a plurality of bracing members  31  fastened between adjacent leg members  30 . With three leg members  30  present, one bracing member  31  connected between adjacent leg member  30  requires a total of three bracing members  31 . As seen in FIGS. 1-4, each of the preferred four leg members  30  is connected to the two adjacent leg members  30  by two pairs of bracing members  31   a  and  31   b,  with one bracing member of the pair,  31   a   1 , positioned above the other brace member  31   a   2 , of the pair. Thus, each leg member  30  has a total of four brace members,  31   a   1 ,  31   a   2 ,  31   b   1  and  31   b   2 , connected to adjacent leg members  30 . This construction provides a rigid base for elevating the rectangular work surface member  20  by means of the height adjusting leg members  30 . 
     The height adjusting leg members  30  are each comprised of a bracket member  32  secured to the bottom side  24  of the work surface member  20 . The upper portion of the leg members  30  is shown in grater detail in FIG.  5 . Referring to FIG. 5, the bracket member  32  includes two pairs of circular fastener members  34  with interior apertures  36 . The fastener members  34  are aligned such that a retaining rod member  38  can extend through all fastener member apertures  36 . A hollow cylindrical collar member  40  is positioned between each pair of circular fastener members  34  with the retaining rod member  38  passing through each collar member  40 . A fastening screw member  42  secures each collar member  40  to the rod member  38 . One end of a tie rod member  44  is located between the pair of fasteners  34  with the rod member  38  passing through an aperture in the end of the tie rod member  44 . A pair of hollow cylindrical rubber bushing member  46  are positioned on the rod member  38 , one bushing member  46  on each side of the end of the tie rod member  44 , and between the pairs of fastener member  34 . The rubber bushing members  46  allow the tie rod member  44  to swivel slightly on the rod member  38 , but prevent damage to the tie rod member  44  and adjacent fastener members  34 . The tie rod member  44  is part of a telescoping support member  50  providing height adjustment of the leg member  30 . 
     The telescoping support member  50  extending from each bracket member  32  is oriented generally perpendicular to the work surface member  20  and fastened to the bracket member  32  through the tie rod member  44 . The telescoping support member  50 , preferably a gas shock cylinder member, expands and contracts by pressurized gas, thereby moving the tie rod member  44  away from or toward the support member  50 . The pairs of bracing members,  31   a  and  31   b,  are secured to the top and bottom of the telescoping support member  50  with each pair of bracing members fastened to an adjacent telescoping support member  50 . The bracing members  31  are preferably rigid steel material. An expandable dust boot member  51 , made of natural or synthetic polymer, encircles the tie rod member  44  at the point the tie rod member  44  enters the telescoping support member  50 . Suitable support material fastens the telescoping support member  50  and the bracing pairs  31   a,    31   b.  The end of the telescoping support member  50  opposite the tie rod member  44  is connected to a rigid leg member  52  through a lockable pivot member  54 . FIG. 6 is a close up view of the lower portion of the height adjustable leg member  30  viewed from the perspective of FIGS. 2 and 3. The box-like U-shaped pivot member  54  includes a transverse top portion  56  with opposing leg sections  58 . The U-shaped member  54  is secured at the transverse top portion  56  to the telescoping support member  50  and attached bracket members  31   b  opposite the tie rod member  44 , and is sized to accept the rigid leg member  52  between the opposing leg members  58 . A pivot pin member  60  extends through each opposing leg sections  58  and through the rigid leg member  52  positioned there between, allowing the leg member  52  to pivot. The rigid leg member  52  is preferably a hollow rectangular steel tube. Pivoting of the leg member  52  is limited to one direction by means of a leg stop member  62  secured to one edge surface of each leg sections  58 . A locking pin member  64  is present in the pivot member  54  which reversibly locks the rigid leg member  52  in the perpendicular orientation. The locking pin member  64  fits into a pair of aligned apertures, one in each opposing leg member  58  of the pivot member  55 . The portion of the leg member  52  positioned within the pivot member  54  contains two sets of apertures as well. One set aligns with the locking pin apertures with the leg member  52  in a vertical orientation, while the other set of apertures aligns with the locking pin apertures with the leg member  52  in a horizontal orientation. The locking pin member  64  is inserted through the appropriately aligned apertures to lock the leg member  52  in the desired orientation. 
     The ends of the rigid leg members  52  opposite the telescoping support member  50  may rest directly upon the supporting surface S. However, it is preferred that a lockable wheeled castor member  66  be secured at the end of each rigid leg members  52  opposite the telescoping support member  50 . Thus, the plurality of height adjusting leg members  30  secured to the planar rectangular work surface member bottom side  24  each preferably have a lockable wheeled castor member  66  attached thereto, allowing the adjustable work surface device  10  to be positioned at one location, and then conveniently rolled to another location. 
     Further, the pivotally fastened rigid leg members  52  each can be unlocked and pivoted about each pivot member  54  from a vertical orientation to a parallel orientation relative to the work surface member  20 . Preferably, the rigid leg members  52  remain beneath the external limits of the work surface member  20  when pivoted to a horizontal orientation. The pivot point for the rigid leg members  52  is located in the pivot member  54 , a selected distance from the planar work surface member bottom side  24 . Several fork lift bracket members  68  may be fastened to the bracket members  31  as seen in FIG.  3 . The tines of a fork lift are inserted into the bracket members  68  for lifting and transporting the device  10 . The whole adjustable work surface device  10 , with the rigid leg members  52  folded to a horizontal orientation, may be stacked by use of a fork lift or similar means when the unit is not in use. 
     The telescoping support member  50  of each height adjusting leg member  30  is supplied and powered with compressed gas delivered by an individual compressed gas conduit member  70 . The conduit member  70  preferably is a flexible hose member, or similar flexible conduit, which connects each telescoping support member  50  with a pneumatic control device  72  mounted by means of a bracket holder member  74  secured to one or more of the bracing members  31 . The individual compressed gas conduit members  70  are preferably fastened to the bracing members  31  of the work surface device  10  and are attached to each telescoping support member  50 . 
     The pneumatic control device  72 , fastened to the bracket members  31 , contains individual control switch members  78  adapted for admitting gas to or releasing gas from individual telescoping support members  50 . The pneumatic control device  72  is shown in greater detail in FIGS. 7 and 8. Referring to FIG. 7, a front view of the pneumatic control device  72  containing the individual control switch members  78  is shown. A pair of control switch member,  78   a   1  and  78   b   1 , is present for each telescoping support member  50 , with the pair of switches positioned vertically. In the embodiment shown in FIG. 7, four pairs of control switch members,  78   a   1 - 4  and  78   b   1 - 4 , are present. Pressing one upper switch, for instance  78   a   2 , admits compressed gas to one of the telescoping support member  50 , through the flexible conduit member  70 . Pressing the corresponding lower switch of the pair, in this case  78   b   2 , releases gas from that same telescoping support member  50 , again through the flexible conduit member  70 . Compressed gas is supplied to each inlet control switch via a common compressed gas manifold channel  80  in the control device body member  81 , in turn supplied from the gas inlet connector  82  positioned at one end of the pneumatic control device  72 . The interior construction of the pneumatic control device  72  is best seen in FIG. 8, which is a cross sectional view along line C—C of FIG.  7 . 
     The upper control switch member,  78   a,  controls a corresponding inlet tank valve member  84   a,  positioned in communication with the gas inlet manifold channel  80 . A supply channel  86   a  in the body member  81  routes the compressed gas to a coupler plug member  88 , opposite the control switch  78   a,  connected to a conduit member  70  supplying one telescoping support member  50 . The supply channel  86   a  is also in communication with a gas outlet channel  90   a  in the body member  81 , controlled by the lower control switch member  78   b.  The outlet channel  90   a  is also in communication with the ambient atmosphere exterior the pneumatic control device  72 . Switch member  78   b  maintains the gas outlet channel  90   a  in a closed condition to retain gas therein. Pushing control switch  78   a  introduces compressed gas to the corresponding telescoping support member  50  via the flexible conduit member  70 , while pushing the switch member  78   a  opens the outlet conduit, allowing compressed gas to escape from the corresponding telescoping support member  50  via the flexible conduit member  70 . The body member  81  of the pneumatic control device  72  is preferably made from block aluminum for ease of machining and durability. Other compositions, such as ferrous based alloys or synthetic resin polymer, are also contemplated for the body of the pneumatic control device  72 . 
     The pneumatic control device  72  is supplied with compressed gas from a compressed gas source  92  via a main gas supply conduit member  94 , reversibly attached to the pneumatic control device  72  by the connector member  82 . The compressed gas source  92  may be a machine, such as a press, which generates work pieces that are moved to the adjustable work surface device  10 . Alternatively, the compressed gas source may be a compressed gas cylinder  96  alone, or a cylinder in combination with a powered compressor pump which compresses the gas. In the case where the compressed gas source  92  is a machine which produces work pieces, disconnecting the gas supply conduit member  94  from the pneumatic control device  72  mounted on the adjustable work surface device  10 , and substituting a second adjustable work surface device  10  of similar construction, reduces redundant equipment and speeds production. 
     The versatility of the described work surface device  10  is further increased by the addition of a second pneumatic control device bracket holder member  74   a  on the side of the work surface device  10  opposite the first bracket member  74 . The second bracket member  74   a  allows the pneumatic control device  72  to be move to the opposite side of the work surface device  10  is so desired. The flexible conduit members  70  and  94  allow for this versatility. 
     Additionally, a machine control device  100 , with a control conduit line member  102  from the machine, can be mounted to the work surface device  10  by means of another bracket member  104 . The machine control device  100  is held in the bracket member  104  by a lock pin member  106 . A similar bracket member  104  mounted on other work surface devices  10  allows interchange of one device  10  for another, with the machine control device  100  simply transferred from one device  10  to another. The machine control member  100  mounted on work surface  10  allows the user to conveniently operate the machine and attend to duties at the work surface device  10 . 
     The advantages of the adjustable work surface device  10  of the present invention are most apparent where the same adjustable work surface device  10  is operated by a number of different users in various locations in a manufacturing facility. Each user is of individual stature, and the height of a given work surface device  10  is not suitable for all users. The capability of the adjustable work surface device  10  of the present invention to adjust in height for each user is unique. The adjustable work surface device  10  can provide a level working surface on an uneven support surface S. Further the work surface device  10  can be adjusted to tilt from side to side, or from front to back at the desire of the user. The tilting of the adjustable work surface device  10  is illustrated in FIG. 3 where both height adjustable leg members  30  at one end of the device  10  are extended to elevate one end of the device, and in FIG. 4 where both leg member  30  at one side of the device are extended to tilt the device to one side. The rotatable attachment of each tie rod member  44  to each bracket member  32  allows the work surface member  20  virtually unlimited adjustment of orientation. 
     With regard to the work surface member  20 , one embodiment thereof is a simple container such as a chute device  120 . The chute device  120  has a flat, horizontal bottom work surface  122  to which the height adjustable leg members  30  are attached. The chute device  120  has vertical sides member  124  and vertical end member  126 , thereby forming an open top container. The pneumatic control device  72  and machine control member  100  are fastened by brackets,  74  and  104  respectively, to one or more of the bracing members  31  for convenient access by the user. An optional extension surface member  128  is positioned at one end of the chute device  120 , with the extension surface member  128  fastened at one edge to the top of the vertical end member  126 . 
     In an alternative embodiment, the work surface device  20  is a conveyor belt device  150 . The conveyor belt device  150  is positioned within the chute device  120 , with a pair of roller members  152  positioned within the chute device  120  at opposite ends thereof and rotatably secured thereto. The chute device  120  constitutes a planar frame member of the conveyor belt device  150 . A continuous belt member  154  encircles the two roller members  152  with the upper surface of the continuous belt member  154  level with the top edge of the chute device  120 . A motor device  156  rotates one or more of the roller member  152 , thereby causing the belt member  154  to rotate, thus delivering work pieces from one end of the conveyor belt device  150  to the other end thereof. A suitable control switch member  158  for the motor device  156  is present, preferably mounted on one vertical side of the chute device  120 . 
     While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.