Note: Descriptions are shown in the official language in which they were submitted.
SUMMARY OF THE INVENTION
-
The present invention relates to a combination gladhand
and quick release valve for use in transportation vehicles such
as over-the-road trucks or the like.
A primary purpose of the invention is a gladhand having
in combination therewith a quick release valve so as to connect
the gladhand outlet to atmosphere upon a reduction in air pres-
sure at the gladhand inlet.
Another purpose is a simply constructed reliably oper-
able combination gladhand and quick release valve in which the
quick release valve will vent the downstream side of the air
system to atmosphere.
Other purposes will appear in the ensuing specifica-
tion, drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated diagrammatically in the
following drawings wherein:
Figure 1 is a side view, in part section, of a combina-
tion gladhand and quick release valve,
Figure 2 is a bottom view of the combination structure
of Figure 1,
Figure 3 is a side view of the combination structure
of Figures 1 and 2, and
Figure 4 is a section along plane 4-4 of Figure 1.
--2--
~5~
DESCRIPTION OF THE PREFERRED EMBODIMENT
The air brake systems of over-the-road vehicles such
as tractor-trailer combinations use what are known as spring
brakes for emergency brake applications. In a spring brake the
brake is maintained in an unoperated condition by air pressure,
and a reduction in that air pressure permits a heavy duty coil
spring to rather quickly apply the brakes. Thus, the reduction
of air pressure within the spring brake chamber, permitting the
brake spring to function is critical in terms of a quick or rapid
operation of the emergency brakes. Due to the rather lengthy
air line in vehicles of this general type, there may be a sub-
stantial time lag between the air signal indicating or requesting
an operation of the spring brake and a reduction in air pressure
sufficient to permit the operation of the spring brake. It was
for this reason that the concept of a quick release valve was
introduced into such vehicle air brake systems several years
ago.
With the change in government regulations permitting
a combination of two trailers and a single tractor, the air system
from the tractor back to the spring brakes on the last trailer
has become even longer, thus causing an even greater time lag
between the signal for operation of the spring brakes and a reduc-
tion in pressure sufficient to permit their operation. Accordingly,
the present invention combines a quick release valve with the
conventional gladhand which will form the connection between
the air systems of the tractor and the trailer and between one
trailer and the following trailer. This will permit a faster
spring brake operation as the quick release valve will vent the
air system on the downstream side of the gladhand. Accordingly,
the spring brakes of each of the trailers will be independently
vented upon receipt of a reduction in pressure from an operator
air signal. This independent venting occurs because the air
within the constant pressure line that normally supplies the
air tanks of all the trailing vehicles is vented at each vehicle
instead of needing to be passed through to the exhaust located
at the control valve on the leading or towing vehicle. A result
of the faster spring brake application is that the spring brake
actually sets the foundation brake with a higher brake force
which not only results in faster stops, it also results in less
brake fading and fewer cracked brake drums.
In this same context, the size of the air pipes used
to provide an air signal to operate the normal air brake chamber
has been decreased. To speed up brake application to trailed
vehicles, quarter-inch pipes are becoming increasingly common
in usage, and while the smaller diameter pipes speed up brake
applications, because less air is required to fill the volume
of the pipes, the smaller diameter can cause surface frictions
resulting in a slower brake release, especially if all of the
air from the control line of the trailed vehicle need pass through
to the piping of the lead or towing vehicle before being vented
to atmosphere.
The present invention provides a combination gladhand
and quick release valve which permits the spring brake of a
trailed vehicle to be actuated more quickly and positively and
also permits the normal air brake chambers of a trailed vehcile
to be released faster than if the air in the control line needs
to be exhausted at the leading or towing vehicle.
In the drawings, a conventional gladhand body 10 has
an air inlet 12 and an air outlet 14. Outlet 14 is surrounded
by the conventional gladhand seal 16 which will mate with a
similar gladhand structure, with such structure plus the body
10 forming the conventional gladhand. There is a passage between
inlet 12 and outlet 14 which is indicated àt 18 in Figure 4,
which passage includes a chamber 20, illustrated in Figure 1,
and a somewhat enlarged portion 22 which is directly in communi-
cation with outlet 14. The gladhand may have the conventional
mounting bracket 24 and bolt openings or the like 26.
--4--
Positioned within chamber 20 i5 a quick release valve
indicated generally at 2~ and including a fixed valve member
30 threaded into the walls of the chamber. There is a passage
32 in valve member 30, which passage terminates in an atmosphere
opening 34 closed by a flapper valve 36. Valve 36 may include
a retainer 38 and a flexible valve member 40 which will move
to an open position responsive to air under pressure within pas-
sage 32.
A movable valve member or diaphragm is indicated at
42 and has a raised position or boss at the left-hand side indi-
cated at 42A and a similar raised portion or boss on the right
side indicated at 42B. Diaphragm 42, subject to air pressure
within chamber 20, will be effective to either open or close
the quick release valve, as described hereinafter.
In normal operation of the gladhand, the air pressure
at the inlet and outlet sides will be equalized and thus diaphragm
42 will be in a position whereby its boss 42B will extend into
passage 32 in valve member 28 to close the passage and thus close
any communication with atmosphere or vent opening 34. There
will be open communication between the inlet and the outlet of
the gladhand. Air pressure within chamber 20 will force the
diaphragm to the described quick release valve closing position.
In the event there is a reduction in air pressure at
the inlet side to cause operation of the emergency or spring
brakes, or through the release of the normal brakes by a reduction
of air pressure in the normal air brake control line, the inlet
side pressure will drop below the pressure at outlet 14 with
the result that the diaphragm will move to the left whereby its
boss 42A will be inserted into the inlet passage opening for
chamber 20. Thus, the inlet side of the gladhand will be closed
and outlet side 14 will be directly connected to atmosphere through
the quick release valve, specifically its passage 3~ and its
vent opening 34. Accordingly, pressure on the downstream side
of the gladhand will be vented to atmosphere directly through
_5_
S~304
the quick release valve.
Whereas the preferred form of the invention has been
shown and described herein, it should be realized that there
may be many modifications, substitutions and alterations thereto.
--6--
