Mechanical arm mechanism for movably supporting multi-position multiple user surface members

A mechanical arm mechanism for moving a user surface such as an electronic monitor for a computer or television and a related keyboard or control board in an arcuate path from a stored position to one or more user positions at various selected elevations and angles of inclination. The mechanism uses at least one set of spaced apart swingable arms each of which has one end pivotally attached to a respective fixed pivot point on a support member and the opposite end pivotally attached to a respective movable pivot point on the bottom or back side of the electronic monitor with the lengths between the fixed pivot points, the moveable pivot points and the arms forming the sides of a quadrilateral which sides change their relative angular orientation as the table or board is moved in its arcuate path of travel. A similar group of swingable arms also forming a quadrilateral are pivotally connected at one end to fixed pivots on the support member and the opposite ends are pivotally attached to the keyboard or control board member to enable such member to move arcuately with the Monitor from the stored to a user position.

FIELD OF INVENTION 
This invention generally pertains to mechanical arm mechanisms which 
movably support multiple user surface members such as, electronic 
television or computer monitors, and their related control boards or 
keyboards and permit such equipment to be moved between a vertical stored 
position and a lowered user position. This type of arm mechanism can also 
support user surface members such as tables or similar board types of work 
surfaces from an initial position to one or more alternative positions. 
More particularly, this invention provides a mechanical arm mechanism which 
may be configured for various sizes of user surface members depending upon 
its application and to a method of determining the multiple parameters of 
the mechanism such as to move the user surface member from an initial 
position to one or more alternative user positions, the method being 
applicable irrespective of the selected alternative user position. 
BACKGROUND OF THE INVENTION 
There are many and various types of mechanical arm mechanisms in the art 
and conventionally each is specific to a particular motion problem. Many 
of these comprise parallel arms or links which must remain parallel 
throughout the motion excursion while others comprise link-and-cam 
arrangements which compensate for possible interference between the links 
as they are moved from one position to an alternative position. Most of 
these prior art mechanisms must function in a limited way to move a table 
or like-type board surface from a first initial position to a second 
alternative user position and the same configuration of arm mechanism may 
not be reconfigured to other applications which effect a change in both of 
the initial and alternative user positions. 
A typical example of a prior art arm mechanism is U.S. Pat. No. 596,931 
issued to F Yunck which shows support arms pivotally attached to a floor 
to support a restaurant stool which can be moved from a horizontal user 
position to a vertical stored position next to a counter. This device is 
limited in its range of movement for its specific purpose and provides for 
no adjustability or for supporting any other kinds of equipment or 
multiple user surfaces. 
The present invention is a further development of my previously mentioned 
copending application 08/574,293 and provides additional versatility for 
handling additional types of user equipment which need to be moved from a 
stored to a user position. The methods of establishing the positions of 
arm members and pivot points as described in my above mentioned prior 
application are equally applicable to this application. For brevity, all 
the prior description will not be repeated herein, however the methods and 
apparatus shown and disclosed therein are incorporated in their entirety 
in this application. 
OBJECTS OF THE INVENTION 
It is an object of this invention to provide a mechanical arm mechanism 
which may be applied to many various types of user surface members and 
equipment such as electronic monitors for televisions and computers and 
their related control boards or keyboards. 
Another object of the invention is to provide a method of determining the 
various and multiple parameters which comprise a mechanical arm mechanism 
such that multiple user surface members may be moved from an initial 
position to an alternative user position, and this, irrespective of the 
selected alternative user position and not being constrained by parallel 
arm motion. 
A further object of the invention is to provide a mechanical arm 
configuration which may comprise a two-arm configuration, a three-arm 
configuration or multiples of these such as to move various sized board 
surfaces from an initial vertical position to any other alternative 
position selected by the user. 
A still further object of the invention is to provide a mechanical arm 
mechanism wherein the various and multiple parameters of the mechanism are 
preselected such as to provide a particular user surface motion exhibiting 
multiple alternative user positions and/or user surface angles. 
These and other objects of the invention will become more fully apparent as 
the description proceeds in the following specification and the 
accompanying drawings. 
SUMMARY OF THE INVENTION 
A mechanical arm mechanism and user surface members in which the arm 
mechanism supports and moves the user surface members in arcuate paths of 
travel between a first and second position located remotely from each 
other at opposite ends of the path of travel comprising: a fixed support 
structure having at least a first and second fixed base pivot means 
attached thereto at spaced distances from each other; a primary user 
surface member; at least one secondary user surface member; at least a 
first and second swingable arm means, each having one end pivotally 
connected to the first and second fixed base pivot means respectively, 
each arm means swinging about it respective base pivot means when the user 
surface members are moved in their paths of travel between the first and 
second position; the opposite ends of the first and second swingable arm 
means being connected to a first and second movable pivot means attached 
to a back side of the primary user surface member; A third swingable arm 
means having one end pivotally connected to a third movable pivot means 
attached to the secondary user surface member and the opposite end 
pivotally connected to a base pivot means about which the third swingable 
arm means swings when the user surface members are moved in their paths of 
travel between the first and second position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows a mechanical arm mechanism indicated by the numeral 20. The 
arm mechanism 20 has at least one pair of arms R1 and R2 each rotatable 
about a pivot point X and Y respectively and movably carrying a primary 
user surface member S1 and a secondary surface ember S2 from a 
substantially vertical or first position where the user surface members 
are indicated as S1' and S2" shown in broken lines to an alternative 
second position shown in solid lines with the user surface members 
indicated as S1 and S2. 
In most instances the raised vertical position is the stored position of 
the user surface members S1' and S2' and the lowered position is the user 
position. The parts referred to as user surface members may be various 
types of equipment but in this invention the most common items of 
equipment are considered to be electronic monitors for television and 
computers forming the primary surface member S1 are control boards or 
keyboards, both sometimes referred to herein as work boards forming the 
secondary surface member S2. 
Still referring to FIG. 1, a fixed support structure 22 is mounted on a 
vertical wall 24 or may be clamped to a horizontal table 26 by one more 
clamps 28. The support structure 22 has three fixed base pivot pins X, Y 
and Z. Swingable arm members R1, R2 and R3 each have one end pivotally 
connected to the respective fixed base pivot pin and the opposite end 
pivotally connected to a respective movable pin A, B, and C attached to 
the backside of the surface members S1 and S2. 
In this embodiment, the arm R2 connects to the pivot B which is joined to 
both member S1 and S2 and forms a common support thereforfor. Arm R1 is 
linked only to member S1 and arm R3 is linked only to the member S2. 
Because of both S1 and S2 being linked together by pivot pin B, both 
members move simultaneously in respective arcuate paths PA, PB and PC 
between the stored position and the user position. 
It should be understood that the assembly of arms R1, R2 and R3 can be 
duplicated in side by side pairs or other combinations as shown in FIGS. 8 
and 9 of my prior application 08/574,293. 
It should also be recognized that while FIG. 1 shows the members S1 and S2 
moved between a vertical stored position and a lowered user position, it 
is also possible to vary the location of the user position as shown in 
FIG. 12 of prior application 08/574,293. It is also possible to adjust the 
angle of the user surface members as shown in FIGS. 13 and 14 of prior 
application 08/574,293. 
FIG. 2 shows an example of how projection lines are used to locate pivot 
pins A, B and C as well as pivot pins X, Y, and Z of FIG. 1. The steps in 
locating the pivot pins are described in the description of FIGS. 2A and 
2B of prior application 08/574,293 and for simplicity will not be 
described in detail in this application. The layout of the lines in either 
application is essentially the same, the only difference in this 
application being that there are two or more user surface members rather 
than one. 
The layout starts by arbitrarily establishing the location of the positions 
of member S1 and S2 in the stored and user position. Then by plotting 
lines PA, PB, PC, which converge to establish reference points, A1P and 
A2P, this establishes areas RX and RZ within which fixed pivot pins X, Y, 
and Z may be located. Lines PX, PZ, CX, CY, and CZ are then drawn in to 
establish the location of movable pivot pins A', A, B', B, C' and C. 
Having established fixed pivot pins X, Y and Z and movable pivot pins A, B, 
and C the arms R1, R2 and R3 can be drawn in between the respective pivot 
pins and the length of the arms is thus established between their pivot 
pins. 
The same sequence of establishing points and plotting lines can be followed 
for any arm assembly regardless of the number of arms and pivot points and 
regardless of the angular positions of the user surface members within 
their paths of travel. The arm and pivot pin layout for the other 
embodiments shown in the following FIGS. 6 through 11 can follow the same 
sequence as that shown in FIG. 2 for laying out the embodiment of FIG. 1. 
Referring now to FIG. 3A simplified diagram showing a pair of arms R1 and 
R2 are shown extending between pivot pins X and A and Y and B 
respectively. A line between pivots X and Y is identified as 30 and a line 
32 extends between pivots A and B. In FIG. 3B line 32 has been shortened 
while the arm R2 has been lengthened. This causes the angle of the line 
32, which represents the plane in which the user surface member lies, to 
change in FIG. 2 from its angle in FIG. 3A. This can be accomplished by 
the mechanism shown in FIGS. 12 and 13 of my prior application 08/574,293. 
In making such angle change, the total distance of the four lines around 
the quadrilateral does not change since the leg R2 is lengthened the same 
amount that line 32 is shortened. 
FIG. 4 shows how that three or more sets of quadrilaterals may be used 
together to form a system for supporting three or more user surface 
members with each member being movable to separate angles relative to the 
others members. FIG. 4 functions on the same principle as the embodiment 
of FIG. 1 but with more arms supporting more user surfaces. 
FIGS. 5A through 5E shows a simplified side view of a group of three user 
surfaces members S1, S2 and S3 with the members being moved into different 
relative angles depending upon the angular positions required by the 
particular use. 
FIG. 6 shows a diagrammatic side view similar to FIG. 1 but of a different 
embodiment in which the primary user surface member T1 is a computer 
monitor and the secondary user surface member is a computer keyboard. As 
may be seen when viewing FIGS. 6 through 7B, The computer T1' and keyboard 
T2' is in a nesting stored position in FIG. 7A and they occupy a common 
space. In FIG. 7B the computer T1 and keyboard T2 are moved to a lowered 
user position with the computer T1 assuming an angle with a higher angle 
of inclination and the keyboard T2 assuming a lower angle nearer to a 
horizontal position for ease of typing on the keyboard. In the lowered 
user position the computer T1 and keyboard T2 no longer are in a nesting 
position with each other. The numerals of like parts of FIG. 1 remain the 
same as in FIG. 1. Unlike the embodiment of FIG. 1 there is no common arm 
connected to both member T1 and T2. T1 is supported by arms L1 and L2, 
while member T2 is supported by a separate pair of arms L3 and L4. Each of 
the pivot pins A1, A2, B1 and B2 move in respective separate arcuate paths 
, , PB1 and PB2. 
While not shown in the drawings, the members T1 and T2 can be mechanically 
linked together by various know means so movement of members T1 and T2 
takes place automatically at the same time to permit smooth action of the 
members being moved from the stored to the user position and likewise when 
being returned to the stored position. 
Referring now to FIGS. 8 through 11, these represent another embodiment in 
which all the working parts are similar except that in the different 
variations, the member T2 is moved about pivot C by four different linkage 
arm locations indicated by linkage arms R4, R4A, R4B and R4C shown 
respectively in FIGS. 8, 9, 10, AND 11. Each linkage arm instead of being 
attached to a pivot pin on the support structure 22, is pivotally 
connected to one of the arms R1 or R2 at a designated location, so that as 
the arm which it is connected to moves in an arcuate path it moves the 
pivot pin holding the respective linkage arm and thereby causes the 
linkage arm to move with the pivot pin. 
For example in FIG. 8 as the arm R2 moves, the pivot pin D moves pulling 
the linkage arm R4 with it. The opposite end of the arm R4 is pivotally 
connected to pivot pin E, through arm R3 connected to the member T2 and 
pivot pin C. As the arm mechanism 20b supporting members T1 and T2 is 
moved from the lowered user position shown in solid lines to the stored 
position shown in chain dotted lines, the linkage arm R4 causes the user 
surface member T2 to fold up as shown in T2'. The same action occurs with 
the other alternate arms R4A, R4B, and R4C shown respectively in FIGS. 9, 
10, and 11. When the user surface members are moved to the user position, 
the linkage arm causes the member T2 to unfold to the desired position for 
use. 
In FIGS. 8 through 11, the member T1 could be a monitor for either a 
television or computer screen and the member T2 could be a control board 
or keyboard. 
While there are three basic variations of arm assemblies shown in this 
application, the basic features of all the variations is that a primary 
user surface member such as an electronic monitor is supported by legs 
forming at least one quadrilateral geometric figure and a secondary user 
surface member such as a control board or keyboard in moved by at least an 
additional arm which causes it to move with the primary user surface 
member when the entire arm assembly and user surface members are moved 
back and forth between a stored position and a user position. 
Various other modifications can be made in the embodiments shown and 
described herein without departing from the scope of the invention.