Quick release mechanism and supporting device having a quick release mechanism

A quick release mechanism for locking a tubular leg member to a supporting structure whereby a >-shaped flat metal spring exerts upward pressure on the handle end of a lever arm causing the lower operating end of the lever arm to force a locking pin into the locked position in the supporting structure. The pin is unlocked by pressing down on the handle end of the lever arm. The quick release mechanism may be secured to legs of a supporting device so that the legs can be readily pivoted into a number of positions, particularly an extended position for support and a spaced parallel arrangement for storage.

BACKGROUND OF THE INVENTION 
This invention relates to a quick release mechanism for pivotally joined 
tube members and more particularly for use on foldable legs attached to 
supporting structures for outdoor signs or barriers. 
There are a number of occasions when it is desired to releasably attach a 
tube or the like to a structure. For example, a number of tubular legs are 
required for the mounting base for outdoor signs and barriers which 
provide information and limitations. This is particularly so along vehicle 
roadways and pedestrian pathways where there is a need to inform the 
public of some road construction or limitation. Frequently, the need is 
temporary and thus it is very advantageous to have mounting bases for such 
signs and barriers which may be readily assembled and disassembled with 
very little effort on the part of the worker. 
Some mounting bases have multiple leg flanges or the like, usually four, 
extending from the lower frames and an equal number of foldable and 
extendable legs pivotally mounted thereto. The legs, when locked to the 
flanges in a horizontal position, support the sign in the work area. In 
order to obtain a compact structure which takes up less room when the 
mounting base is not in use, the pivotally mounted legs are quite often 
folded upwards and temporarily attached in a vertical position to the 
flanges. 
Heretofore, such attachments have been accomplished by removable pins, 
bolts, clips or by being manually tied-upright. 
A frequently used attachment has been a pin assembly. The pin is attached 
to a coil spring within the tube leg. This requires drilling holes in the 
pin, inserting small needles therein and attaching the coil spring 
thereto. To lock the leg to the flange, an opening in the leg is aligned 
with openings in the flange and the pin is forced inwardly through the 
openings into the engaged position. The pin is unlocked by pulling it out 
of the opening. 
However, the constructions most frequently used have not been satisfactory. 
They are often awkward and time consuming operations. They require a great 
deal of effort on the part of the worker. In many cases to release the pin 
from the locked position, the worker must remove his gloves and use both 
hands in order to unlock the system. In most cases the worker has to bend 
over to perform the unlocking. There are also complicated coil spring-pin 
attachments that are difficult to manufacture and to operate. 
There is a need for a simple quick release mechanism which securely locks 
and readily unlocks tubular members with very little effort on the part of 
the worker. 
SUMMARY OF THE INVENTION 
In accordance with the present invention, a quick release mechanism is 
provided which solves the problems of the prior art. 
The quick release mechanism of the present invention is mounted on a 
tubular member, for example, the tubular legs of a mounting base for 
outdoor signs and barriers. The quick release mechanism includes a lever 
arm, a pin and a resilient member. The lever arm is pivotally attached to 
the tubular leg. The pin passes through and extends beyond both sides of 
the tubular leg and loosely rides within a slot at the operating end of 
the lever arm. The resilient means fits beneath the handle end of the 
lever arm being in tensional contact with the outer surface of the leg and 
the bottom surface of the lever arm. 
To lock the leg in any position, such as in either the horizontal support 
position or in the upright compact position, the pin is pushed inwardly to 
an engaged position in the leg flange by the operating end of the lever 
arm. The pin is unlocked by pressing on the handle end of the lever arm 
which pulls the pin out of the engaged position in the leg flange. 
The resilient means is designed to be always in tension. It puts upward 
pressure on the under side of said handle end of the lever arm in order to 
keep the operating end of the lever arm in the downward position forcing 
the pin in the engaged locked position. 
The resilient means preferably includes a piece of metal, plastic or rubber 
or similar material preferably 
shaped which is fitted beneath said handle end of the lever arm in 
tensional contact with the inner surface of said handle end of the lever 
and the outer surface of the tubular leg. 
Accordingly, it is an object of the present invention to provide a quick 
release mechanism which securely locks and readily unlocks tube members to 
and from a structure. 
It is a further object to provide a quick release mechanism which can be 
easily and quickly operated with little effort on the part of the worker. 
It is another object to provide a quick release mechanism which can lock 
and unlock members in horizontal and upright positions. 
It is another further object to provide a quick release mechanism which is 
a simple structure containing few parts which is easy to manufacture and 
assemble.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A preferred embodiment of the quick release mechanism of the present 
invention is illustrated in the drawings of a mounting base for a highway 
sign requiring supporting leg members. 
Referring to FIG. 1, sign 10 is attached to a mast 12 which is supported 
vertically upon a mounting base 14. The mounting base generally has four 
leg flanges 16 and an equal number of tubular legs 18 pivotally attached 
thereto. Although tubular legs 18 as shown are rectangular, it is not to 
be so limited. Any tubular configuration is operable such as circular, 
square, etc. 
FIG. 1 shows the sign structure being supported while in use in the work 
area. Generally, each leg flange 16 includes two openings such as openings 
20 and 22 which, as shown, completely penetrate the leg flange but are not 
required to do so. Only enough opening to lock the pin in place is 
required. 
Legs 18 support the structure in use by being locked in an horizontal 
extended position by means of a pin passing through opening 21 of the leg 
into opening 20 of the flange (FIGS. 1 and 3). FIG. 2 shows the sign 
structure with the legs locked in the upright compact position by means of 
the pin passing through opening 21 of the leg into opening 22 of the leg 
flange (FIG. 3). 
The construction and operation of the quick release mechanism are best 
understood by reference to FIGS. 3 and 4. Quick release mechanism 24 
includes three components: a lever arm 26, a pin 34 and a resilient member 
such as a flat metal spring 38. The lever arm 26 is attached to the 
tubular leg 18 by hinge 28 or similar means which allows the lever arm to 
pivot. Pin 34 extends through both sides of leg 18 and may penetrate 
openings 20 or 22. A first end of pin 34 fits within slot 30 of lever arm 
26. The lever arm 26 loosely engages the pin 34 within groove 36. 
Groove 36 generally is located just below the first end of the pin. The 
groove has a smaller diameter than the rest of the pin and is cut to such 
dimensions so that it rides freely within slot 32 in an up and down 
movement. The second or locking end of pin 34 is forced into opening 20 or 
22 of the leg flange when tubular leg 18 is in the locked position. 
The resilient means is located beneath the handle end 27 of lever arm 26 to 
force that end of the lever arm 26 to an upright position at an angle of 
about 30.degree. from the horizontal tubular leg when in the locked 
position. The resilient means is preferably a &gt;-shaped piece of flat metal 
spring 38 which snugly fits between the handle end of the lever arm 26 and 
the tubular leg 18. Apron wall 29 of the lever arm 26, when in the locked 
position, extends downwardly about 40% of the distance to the tubular leg 
and prevents the flat metal spring 38 from slipping out of position. Apron 
wall 29 also limits the movement of lever arm 26 and pin 34 by acting as a 
stop to the downward movement of the lever arm. 
It is to be understood that flat metal spring 38 of the preferred 
embodiment is of the type formed of flat spring steel having a high degree 
of memory, high tensile strength and high yield point. A triangular piece 
of stainless steel is the preferred material. 
The &gt;-shaped flat metal spring 38 is designed to be in constant tensional 
contact with the lever arm and the tubular leg. In the locked position, it 
exerts upward force on the lever arm's handle end 27 thus moving the lever 
arm's operating end downwardly towards the leg surface to force pin 34 
into a locked position. 
Pin 34 is disengaged from the locked position by exerting downward pressure 
on the handle end 27 of the arm, resulting in the grooved pin being lifted 
out of opening 20 or 22 to the unlocked position. The leg is then moved to 
the desired position. 
There are several advantages to the quick release mechanism. Only three 
components are required: lever arm 26, pin 34 and triangular flat metal 
spring 38. The components can be easily manufactured. They can be readily 
assembled into a simple mechanism which is easily attached to a tubular 
structure. 
Further advantages are that the unique assembly of these components results 
in an unexpectedly smoothly operated mechanism with very little effort on 
the part of the worker. Pin 34 is made to smoothly fit in the openings 20 
and 22 of the leg flange. Groove 38 of the pin and slot 30 of the 
operating end of the lever arm are cut to such dimensions so that the 
grooved pin rides loosely in up and down movements within the slot 30. 
Flat metal spring 38 is prepared from material having such dimensions and 
&gt;-shaped designs to fit snugly beneath handle end 27 of the lever arm to 
keep constant upward pressure therein yet readily yields to downward 
pressure applied to the handle and to release the pin from the locked 
position. Apron wall 29 extends downwardly a sufficient distance to 
contain the flat metal spring in its operating position and to control the 
downward movement of the handle end and the upward movement of the 
operating end of the lever arm. Hinge 28 is set closer to the operating 
end of the lever arm, about 40% of the distance from end to end, to 
coordinate the functioning of all of the elements of the quick release 
mechanism. 
Further, it will be apparent to those skilled in the art from the foregoing 
description and accompanying drawings that additional modifications and/or 
changes of the disclosed embodiment may be made without departure from the 
invention. Accordingly, it is expressly intended that the foregoing 
description and accompanying drawings are illustrative of a preferred 
embodiment only, not limiting, and that the true spirit and scope of the 
present invention be determined by reference to the appended claims.