Abstract:
An improved work area for laminate constructions that is designed to amplify the holding force from that supplied thereto and which accommodates materials of various sizes and configurations.

Description:
BACKGROUND 
     In order to hold objects to be worked upon it has been suggested in the prior art that one apply a vacuum to a table having openings in its surface which will create suction forces on the object. Various types of structures within the prior art have been suggested such as shown by U.S. Pat. Nos. 3,042,356 and 3,741,116. 
     In the earlier of these an apparatus is described where an upper plate having a plurality of holes therethrough is placed over a corrugated mat made of a flexible material having passages within it leading to slots communicating with a passage open to a port through a support plate thereunder. There is no suggestion in this reference that the structure could support heavy work without obstruction of the fluid flow path of the sandwiched corrugation or that by sizing openings through the outer plate with regard to the outlet passage for the corrugations one could obtain the results desired with much more practical vacuum apparatus. 
     In the more recent patent the support table is made of sheets separated by a honeycomb core. The upper sheet is perforated and each core passage of the honeycomb is connected. Therefore, a vacuum drawn through the bottom plate evacuates the entire core in obtaining a negative pressure at the surface for drawing and holding work thereon. 
    
    
     DRAWING DESCRIPTION 
     FIG. 1 is an isometric view of a modular form of work table having a vacuum system connected thereto to controllably use selected areas to hold work to the table; and 
     FIG. 2 is a cross sectioned view of a part of one of the modules for the table of FIG. 1 showing its internal construction and a valving control thereof. 
    
    
     DETAILED DESCRIPTION 
     With more particular reference to FIG. 1 there is shown thereby a work table 10 having a plurality of modular elements 12 in its make-up. Each modular element has one or more openings 14 in its surface portion 16 and one or more outlets 20 in its support portion 18. Outlets 20 communicate with pipe 22 leading to a manifold 24 from vacuum pump 26. 
     The outlets 20 have solenoids 28. A control 30 connects an electrical source to motor 32 for pump 26 and switch box 34 for solenoids 28. 
     With reference to FIG. 2 there is shown a cross-section of an end module along lines 2--2 of FIG. 1. Clearly delineated by such cross section is the construction of surface portion 16 and support portion 18. The former includes a top plate 36 over a honeycomb core 38 on a distributor plate 40. The top plate is drilled to have an opening 14&#39; overlying passages of cores of honeycomb 38 limited by means of annular seals 42 and 44 to define a passageway from the top plate 36 through the distributor plate 40 of a substantially constant diameter. In a form so far constructed this opening was sized at approximately 25.4 mm. 
     The support portion has an orifice plate 46 with an orifice(s) 48 underlying the opening(s) of distributor plate 40. In the unit constructed aforesaid this orifice was sized at 2.15 mm. The support portion has a peripheral sidewall 50 from orifice plate 46 to a porting plate 52 opened as at 54 to port piping 20 having valve 56 controlled by the solenoid 28. A baffle plate 58 is supported by small posts 60 to overlie the opening 54 of the porting plate. This prevents the openings 14 in the immediate vicinity of opening 54 for port piping 20 from being at a greater pressure variance with atmospheric than those away from the opening 54. 
     Not obvious at first is the fact that the above-described structure provides a vacuum handling system which will permit large areas of the vacuum holding surface 12 to be uncovered without severe losses in the holding capability of the system for the area covered by a material to be held to the surface 12. The key concept to be understood is that the structure 10 is in reality a series of vacuum amplifiers which multiplies the static holding force in the ratio of the small port 48 to the area of the opening 14&#39;. More particularly, the larger opening 14&#39; on the surface of modules 12 will permit the static vacuum pressure to be exerted over a large, but controlled area when the hole (opening 14&#39;) is covered by an object to be held thereon. When the object is removed from over the hole the air flow loss to the blower or vacuum system (pump 26) is limited by the size of port (orifice) 48. 
     Having described above an operative construction for this invention it may now be further described and its breadth delineated by the appended claims, as follows: