Plate fastening system

A fastening system is provided for fastening a plate having open-ended slots formed about its periphery to a supporting wall. The system includes a mounting block which is mounted to the supporting wall, a clevis pivoted on the mounting block, the clevis having a main body portion and two legs extending in the same direction from opposite sides of the main body portion with an elongated opening formed in each leg, a roll pin which extends through the elongated openings and into openings formed on opposite sides of the mounting block, and a slotted binder head machine screw which extends into an opening formed in the main body portion of the clevis and which cooperates with the U-shaped slots formed in the plate. The plate fastening system may further include a compressible gasket interposed between the underside of the plate and the supporting wall.

BACKGROUND OF THE INVENTION 
Field of the Invention 
The present invention relates to a new and useful improvement in fastening 
systems adapted to be used in many applications, in particular large 
dehumidification systems, to permit the quick and easy release of access 
panels or the like. 
Access panels on large dehumidification systems are required to be removed 
periodically for inspection and repair purposes. These panels must also 
seal against air leaks. Time and effort may be expended wastefully by 
having to remove access panels which are bolted or screwed to supporting 
or plenum walls of the system. 
OBJECTS AND SUMMARY OF THE INVENTION 
An object of the present invention is to provide an improved fastening 
system which allows quick and easy release of access panels or the like. 
It is a further object of this invention to provide a fastening device 
which consists of a minimum number of components and is easily and 
inexpensively manufactured. 
The improved fastening system basically comprises a fastener subassembly 
which engages an access panel or plate having formed about its periphery a 
plurality of open-ended slots. The fastener subassembly includes a 
mounting block which is affixed by fastening means to a plenum or 
supporting wall of the dehumidification system, a clevis which is 
pivotally mounted on the block and held in place by a roll pin which 
extends through the clevis and the mounting block, the plate fastening 
means adjustably mounted on the clevis to secure the plate to the plenum 
wall. 
Other objects and advantages reside in the details of construction and 
operation as more fully hereinafter described and claimed, reference being 
had to the accompanying drawings forming part hereof, wherein like 
numerals refer to like parts throughout.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings of the illustrated embodiment and initially 
to FIG. 1, it will be seen that a plate fastening system comprises a 
fastener subassembly 1 which is mounted on a supporting or plenum wall 2 
and positioned to abut a flange 3 extending perpendicularly from the wall. 
The fastener subassembly 1 is used to fasten an access panel or plate 4 to 
plenum wall 2. Plate 4 has formed about its periphery at predetermined 
locations above each fastener subassembly 1 a plurality of U-shaped slots 
5. Each slot 5 is open-ended at the peripheral edge 6 of plate 4. Slot 5 
is dimensioned to receive the shank 7 of a machine screw or bolt 8 which 
projects outwardly from the fastener subassembly 1. The width of slot 5 is 
limited to prevent the head of machine screw 8 from slipping therethrough. 
Plate 4 may have a lip 9 about its periphery which is angled downwardly 
toward plenum wall 2. With lip 9, screw 8 need not be loosened 
substantially to swing clear of edge 6; this facilitates the removal of 
plate 4. If an airtight seal is required, a compressible gasket 10 may be 
interposed between flange 3 of plenum wall 2 and the underside of plate 4. 
When plate 4 is secured to plenum wall 2, the edge of flange 3 compresses 
a portion of gasket 10 whereby forming an airtight seal. 
In FIG. 2 it is seen that fastener subassembly 1 comprises preferrably a 
rectangular mounting block 11, a clevis 12 surrounding a portion of 
mounting block 11 and pivotally mounted thereon, a roll pin 13 inserted 
through openings formed in clevis 12 and mounting block 11, and machine 
screws 8 and 14. 
Mounting block 11 is of solid material and rectangular in shape. An edge 15 
thereof is chamferred at preferably a 45.degree. angle and faces the 
corner formed by flange 3 and plenum wall 2. Formed in the underside 16 of 
mounting block 11 is an opening 17 dimensioned and threaded to receive 
machine screw 14. Machine screw 14, which has a slotted round head 29 and 
which is inserted through a hole 28 formed in plenum wall 2, is used to 
anchor mounting block 11 in position on plenum wall 2. A circular hole 18 
extends through mounting block 11 to side faces 19, its central axis 
disposed perpendicularly to the planes in which side faces 19 lie. Hole 18 
is dimensioned to closely receive and hold roll pin 13 in position. 
Clevis 12 includes a main body portion 20 and a pair of mutually parallel 
legs 21 extending in the same direction from opposite edges of main body 
portion 20 and substantially perpendicular thereto. In each leg 21 is 
formed an elongated opening 22 which is oval in shape. Each elongated 
opening 22 has a width measured along its minor axis which is greater than 
the diameter of roll pin 13, allowing clevis 12 to receive roll pin 13 
through legs 21 and partially rotate about the axis of roll pin 13. The 
elongated length of opening 22 provides sufficient play for radial 
movement of clevis 12 in respect to the axis of roll pin 13. Centrally 
formed in main body portion 20 is a circular opening 23 which is 
dimensioned and threaded to receive the shank 7 of machine screw 8. 
Opening 23 extends through the thickness of main body portion 20 so that 
the tip 24 of machine screw 8 may contact the top side 25 of mounting 
block 11 when plate 4 is secured to plenum wall 2. Machine screw 8 has a 
slotted binder head 26 and is fitted with a nylon washer 27. 
When fastener subassembly 1 is assembled, as shown in FIGS. 3-6, it can be 
seen that clevis 12 is pivotally mounted on mounting block 11 and held in 
place by roll pin 13. 
To remove plate 4 machine screw 8 is loosened. As shown in FIGS. 3-5 with a 
plenum wall and access panel in a horizontal position, the weight of 
clevis 12 and screw 8 and the free play provided clevis 12 by elongated 
openings 22 causes clevis 12 to travel radially toward roll pin 13. This 
allows tip 24 of screw 8 to remain in contact with the top side 25 of 
mounting block 11 and support clevis 12 in an upright position. Screw 8 
remains in its respective U-shaped plate slot 5 with head 26 resting on 
the surface of plate 4. Thus, machine screw 8 remains in a stable position 
even when partially loosened and does not wobble or slide within the plate 
slot; this greatly facilitates removal of the access panel. When loosened, 
machine screw 8 may be lifted so that tip 24 no longer contacts top side 
25 of block 11. Machine screw 8 may then be swung clear of plate edge 6 
with tip 24 clearing the corner 30 of mounting block 11. Clevis 12 will 
rest on its side, as shown in FIG. 3, and plate 4 may then be removed. 
To fasten plate 4 to plenum wall 2, loosened machine screw 8 is inserted 
into its respective U-shaped plate slot 5 and tightened. Tip 24 contacts 
top side 25 of mounting block 11 and forces clevis 12 to move radially 
away from roll pin 13 until the rounded inner edge 31 of elongated opening 
22 contacts roll pin 13. This will secure plate 4 to wall 2. If an 
airtight seal is desired, tightening screw 8 will force the edge of flange 
3 of plenum wall 2 to contact and compress a portion of gasket 10. 
FIG. 6 shows a plenum wall 2' (with a flange 3') and plate 4 in a vertical 
position. It should be noted that when fastener subassembly 1 is loosened 
so that plate 4 can be removed, clevis 12 and machine screw 8 will remain 
in a vertically upright position. This is because elongated opening 22 
allows tip 24 of machine screw 8 to rest on the outer face 32 of mounting 
block 11 and support clevis 12 and screw 8 in such position. 
The preceding description is intended to be illustrative rather than 
limiting. Various changes and modifications in the embodiments described 
herein may be effected by one skilled in the art without departing from 
the spirit and scope of the invention, as defined in the appended claims.