Valve assembly

A valve assembly with a bank or row of switching valves has a base plate of u-like cross section with two flanges and a web therebetween. Within one of the flanges there is a common supply duct and in the other there is a common air outlet duct for the valves placed on the plate. The housings of the valves are generally block-like and their inlet and outlet ports are placed in opposite sides thereof. The sides with the air outlet ports furthermore have electrical connection pins for the solenoid magnets of the valves. A common electrical plug connector is placed covering over the pins of all the switching valves. There is a single muffler for all the switching valves.

FIELD OF THE INVENTION 
The present invention relates to valve assemblies, and more specially to a 
valve assembly having a number of switching valves and a support or base 
plate, on which the switching valves are placed on a common assembly 
surface, or groups of switching valves are placed in their groups on a 
common assembly surface, the valve assembly having a supply duct with 
branch ducts opening through the assembly surface and connection ducts for 
driving loads, said connection ducts communicating with working ports of 
the switching valves. 
BACKGROUND OF THE INVENTION 
Such assemblies or banks of valves are used more specially for building up 
pneumatic program control systems and generally have an assembly plate 
with a common assembly surface for the switching valves that are joined up 
with a common air supply by way of a common compressed air feed line. 
There is a separate air let-off port for each switching valve and each 
such port has its own muffler. 
SUMMARY OF THE INVENTION 
One purpose of the present invention is that of designing a valve assembly 
of the sort noted that is simpler mechanically than known designs and 
takes up less space. 
For effecting this purpose and further purposes there is a common air 
lef-off or waste air duct in the assembly plate for all the switching 
valves or for the groups of switching valves, which duct has branch ducts 
opening through the assembly surface and joining up with air let-off ports 
of the switching valves. 
The valve assembly makes do without separate mufflers or waste air ducts 
for each of the separate switching valves, because there is a common air 
let-off duct in the assembly plate itself for all the switching valves or 
in each case for one group of switching valves. Because of the fact that 
the waste air branch ducts as well are designed opening through the common 
assembly surface, the connections needed in this respect are automatically 
produced on fixing each switching valve in position on the assembly plate. 
The putting together of a valve assembly is for this reason made very much 
simpler and there are less outside connections needing special space. 
Further useful developments of the invention will be seen in the claims. 
As one such further outgrowth of the invention the assembly plate has a 
u-like cross section and the supply duct and the air let-off duct are 
placed within the flanges of the cross-section, the branch ducts opening 
at the inner face of the flanges and the supply ports and the air let-off 
ports of the switching valves opening in opposite side faces of 
parallelpiped-like housing parts of the switching valves. Such a design is 
useful when it comes to miniaturizing the complete valve assembly, because 
the different connection ports of the switching valves may be placed in 
different limiting surfaces of the switching valves so that the valve 
housings may then be made specially small in size while at the same time 
it is possible to make certain that all the desired connections are 
automatically produced every time a switching valve is placed in position 
on the assembly plate. 
It is furthermore possible for the control signal terminals of the 
switching valves to be supported on that side face of the valve housing 
that has the supply port or the air let-off port and for there to be a 
common control signal plug the control signal terminals being placed in 
line one to the back of the other. Such a design is of value in connection 
with producing a simple connection between the valve assembly and a 
control unit. It is then only necessary for one plug to be pushed home or 
for it to be pulled out for joining up the control unit or for unjoining 
it. A further rewarding effect of this development of the invention is 
that the unit formed by the valve assembly and the control signal plug has 
an even smoother outline or surface. 
It is furthermore possible for the flange of the assembly plate with the 
air let-off duct within it to be broader than the flange having the supply 
duct, the control signal terminals being supported by the side face having 
the air let-off port of the switching valve. This makes it possible for 
the air let-off duct to have a large cross section and the space placed 
over the air let-off duct may then be used for the common control signal 
plug. 
It is possible to have positioning pins, placed off center, on the 
switching valves, the pins being taken up in special holes therefor in the 
assembly plate. It is then possible for the different switching valves 
only to be placed facing in the right direction with respect to the 
assembly plate. These positioning pins may have elastic detent means so 
that the switching valves may be locked in position and taken off the 
assembly without the use of tools. This is a useful further development of 
the invention when it comes to replacing valves at a hard-to-get-at point 
on a program control system. 
It is furthermore possible for the assembly to have cover bodies or dummy 
valves that have parts of the very same form as the form of the switching 
valves next to the assembly surface, but with blind holes in place of 
valve connection openings. This makes it possible to make do with one and 
the same sort of assembly plate for building up valve assemblies of 
different degrees of complexity. The spaces on the assembly plate that are 
not taken up by valves have the dummy valves placed on them. 
The switching valves furthermore have a mechanical supporting function in 
connection with the common control signal plug terminal. To make it 
possible for this mechanical supporting or carrying function to be able to 
be used whatever the number of the switching valves on the assembly it is 
possible for at least the cover bodies or dummies placed at ends of the 
assembly plate to be mechanically the same in design with respect to the 
control signal terminals as the functioning switching valves, the control 
signal terminals of the dummies being inactive. With this further 
development of the invention the putting in position and taking off of a 
control signal terminal may be undertaken in quite the same way in every 
case so that there is very much less danger of a control signal terminal 
being put in the wrong position. 
Further developments and useful effects of the invention may be seen from 
the detailed account now to be given using the figures herein

DETAILED DESCRIPTION 
The valve assembly or bank to be seen in the figures has a supporting base 
or assembly plate 10 with a u-like cross section, that is to say with a 
web 12 or floor part and two side flanges 14 and 16. A compressed air 
supply duct 18 is formed in the flange 14 and one end thereof is shut off 
by a stopper 20, and in its other opposite end there is a connector 22 for 
the supply of compressed air into said duct. Branch ducts 24 come off the 
supply duct 18 at regular spacings therealong, such branch ducts opening 
in ports in the inner face of the flange 14. 
The flange 16 is broader than the flange 14 and has an air let-off duct 26 
formed in it which is shut off at the end to be seen on the left in FIG. 2 
by a stopper 28, whereas the end on the right in FIG. 2 is joined up with 
the outside atmosphere through a muffler 30. There are furthermore branch 
ducts 32 running off from the air let-off duct 26 and opening at ports in 
the inner face of the flange 16. 
The web 12 or floor of the assembly plate 10 has terminal connectors 34 
(that is to say connectors with the function of terminals) for connection 
with pneumatic loads, the regular spacing of the connectors 34 being the 
same as that of the branch ducts 24 and 32. Keeping to this same spacing 
the web 12 furthermore has through holes 36 which take up positioning pins 
38 of the valves. These pins are off-center in relation to the lower 
limiting face of the switching valves 40-1 to 40-5 under which the pins 
are placed. 
In the present example the switching valves are 3/2 solenoid valves which 
each have an air inlet duct 42 running towards the flange 14, an air 
outlet duct 44 running towards the flange 16 and a working duct 46 running 
towards the web 12. 
These ducts 42 to 46, which are used for connection of the valves, are air 
tightly joined up by o-rings 48 and 50 and by a further o-ring at the 
working duct 46 with a three-part assembly or mounting face 52 which is 
present in the form of the inner faces of the flanges 14 and 16 and the 
top side of the floor or web 12. In the unassembled condition these 
o-rings respectively project somewhat the opposite end faces (to the front 
and the back in FIG. 1) of a lower valve housing part 54 and beyond the 
lower side of the valve housing part 54 and are elastically squeezed when 
the valve housing part 54, fitting between the flanges 14 and 16 with a 
small amount of play, is pushed into position on the assembly or mounting 
of plate 10. 
A switching valve 40 may only be fitted in position when the supply duct 42 
is opposite to a branch duct 24 and the outlet air duct 44 is opposite to 
a branch duct 32, because it is only in this position that the valves's 
positioning pin 38 may be fitted into one of the through holes 36. As will 
be seen from FIG. 1, the positioning pins have a somewhat barrel-like form 
and have lengthways slots 56, that is to say they are bifurcated, so that 
the two sides of each pin 38 are bent inwardly towards each other 
elastically when they are pushed into the holes 36 and keep the valves in 
position because of the springing effect. In this way it is possible for 
the switching valves 40 to be plugged into the assembly plate 10 and to be 
taken off it again without needing any tools. Because the positioning pins 
38, each acting as a locking pin, are placed right up next to one of the 
working ducts 46 and the terminal connectors 34, the forces produced when 
the working ducts are put under pressure, which have the tendency of 
forcing the switching valves 40 clear of the assembly plate 10, may taken 
up with a short lever arm effect. The forces produced by the effect of the 
pressure in the supply duct 42 on a switching valve 40 are taken up 
without any trouble over the surface of the flanges 16. 
No details of the inside parts of the switching valves 40 are to be seen in 
the figures. In the top part of each such valve there is a driving 
electromagnet which is joined up with driving current by way of pins 58 
and 60, such pins being placed on the same side of the switching valve as 
the air outlet duct 44. The pins 58 and 60 are supported by a top, 
overhanging housing part 62 running out past the outer face which is 
pressed up against the flange 16 of the valve housing part 54. 
For producing an electrical connection between the valve assembly and an 
electrical controller (not shown), use is made of a rail or strip plug 
connector 64 running along all the pins 58 and 60 of the switching valves 
40-1 to 40-5 and joined up with a cable 66 with the desired number of 
cores. As will be seen from the figures, the plug connector 64 has the 
effect of covering over the space over the broader flange 16 as a smooth 
cover in line with rest of the outline of the assembly, the pins 58 and 60 
as well being covered over. The plug connector 64 is supported on all of 
the switching valves 40 equally. 
In the event of one of the switching valves 40-1 to 41-5 not being needed, 
its place may be taken by a valve housing or dummy whose ducts 42 to 46 
have their place taken by blind holes each having its own o-ring. It is in 
this way that the branch ducts coming from the supply duct, the air outlet 
duct and terminal connectors of the web 12 are shut off and put out of 
operation. Such a valve dummy, which is simply used as a stopper and has 
no electrical function, may have pins 58 and 60 in its top part, although 
it would be without any electrical function. In fact the function of such 
a dummy valve is that of making the assembly mechanically the same as one 
fitted only with working, functional valves. If the dummy needed does not 
have to be at the end of the assembly, the dummy may be simpler in design 
and only have a housing representative of the housing part 54, the ducts 
42 to 46 being in the form of blind holes. 
It will be seen that the valve assembly or bank detailed herein is highly 
modular in its design and has more or less smooth sides all the way round. 
It may furthermore be simply fixed in position and upkeep is simple. It is 
simple to make an electrical connection with an electrical controller and 
furthermore a single muffler may be used for all the switching valves. 
It will furthermore be clear that pneumatically functioning valves may be 
used in place of the solenoid valves 40, in which case the plug 64 will be 
in the form of a pneumatic plug terminal and any dummies of stoppers will 
have the same mechanical design of their control signal ports as those of 
pneumatically controlled, fully functioning valves, the only difference 
being that there are blind holes in the place of ducts.