Pumps – One fluid pumped by contact or entrainment with another – Liquid pumped by supplying or exhausting gaseous motive...
Reexamination Certificate
1998-06-09
2001-06-12
Freay, Charles G. (Department: 3746)
Pumps
One fluid pumped by contact or entrainment with another
Liquid pumped by supplying or exhausting gaseous motive...
C417S132000, C137S165000, C137S202000, C137S410000, C137S413000, C004S590000, C004S325000, C261S073000, C074S100100
Reexamination Certificate
active
06244829
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid forced-feed apparatus for feeding a liquid, such as water, fuel, etc., under pressure. The liquid forced-feed apparatus of the present invention is suitable particularly for use in collecting a condensate generated in a steam piping system and feeding this condensate to a boiler or a waste heat recovery system.
2. Description of the Prior Art
Condensate generated in a steam piping system in most cases still has a considerable quantity of stored waste heat. For this reason, it has been a widespread practice to use a condensate recovery system, including a liquid forced-feed apparatus, to recover the condensate and feed it into a boiler or waste heat recovery system. Such a system is designed for the utilization of waste heat from the condensate, thus realizing the effective use of this energy.
The liquid forced-feed apparatus used in prior art condensate recovery systems collects condensate in a hermetic vessel, and introduces a high-pressure working fluid, such as steam, into the hermetic vessel by operating a change-over valve, thereby forcing the condensate from the inside of the hermetic vessel under the pressure of the working fluid.
To ensure high-efficiency operation of the liquid forced-feed apparatus, it is necessary to hold as much condensate as possible in the hermetic vessel and to properly switch the change-over valve. The liquid forced-feed apparatus of the prior art, therefore, generally uses a snap mechanism in order to ensure reliable switching of the change-over valve.
FIG. 1
is a partly sectional perspective view of the type of liquid forced-feed apparatus disclosed in the prior art. The liquid forced-feed apparatus of
FIG. 1
has a hermetic vessel
101
, and contains a float
120
, a changeover valve
130
, and a snap mechanism
140
. The hermetic vessel
101
is provided with a forced-feed liquid inlet port
102
and a forced-feed liquid discharge port
103
in the vicinity of the bottom, which are fitted with check valves
105
and
106
, respectively. The check valve
105
is mounted in a direction such that the condensate is allowed to flow into the hermetic vessel
101
, while the check valve
106
is mounted in a direction such that the condensate is allowed to be forced out from the hermetic vessel
101
.
In the top of the hermetic vessel
101
are formed a working fluid inlet port
108
and a working fluid discharge port
109
, which are fitted with a supply valve
110
and an exhaust valve
111
, respectively. The supply valve
110
and the exhaust valve
111
, which together form the changeover valve
130
, are opened and closed by up and down movement of the valve lifting rods
112
and
113
, respectively. The supply valve
110
is opened when the valve lifting rod
112
is up, while the exhaust valve
111
is closed when the valve lifting rod
113
is up. The valve lifting rods
112
and
113
are connected in parallel by a connecting plate
115
. The supply valve
110
and the exhaust valve
111
are thus simultaneously opened and closed by moving the connecting plate
115
up and down.
In the prior art liquid forced-feed apparatus of
FIG. 1
, the forced-feed liquid inlet port
102
is connected to a load of steam via the check valve
105
, and the forced-feed liquid discharge port
103
is connected to a boiler, and an apparatus utilizing waste heat, via the check valve
106
. The working fluid inlet port
108
is connected to a high-pressure fluid source. When no condensate is present in the hermetic vessel
101
, the float
120
is in the lower position and the connecting plate
115
is down, causing the supply valve
110
to close the working fluid inlet port
108
and the exhaust valve
111
to open the working fluid discharge port
109
.
If condensate is generated in the load of steam connected to the liquid forced-feed apparatus of
FIG. 1
, the condensate flows into and gathers in the hermetic vessel
101
via the check valve
105
. With an increase in the amount of the condensate, the float
120
rises, causing one end of the arm
118
to rise. If the arm
118
rises over a predetermined level, a snap mechanism
140
turns over to raise the valve stem operating rod
121
, thereby raising the connecting plate
115
. As the connecting plate
115
rises, the supply valve
110
opens the working fluid inlet port
108
and the exhaust valve
111
closes the working fluid discharge port
109
. The pressure in the hermetic vessel
101
then increases, forcing the condensate under pressure out of the forced-feed liquid discharge port
103
via the check valve
106
.
SUMMARY OF THE INVENTION
The prior art liquid forced-feed apparatus is of a simple construction and is capable of forcing the liquid comparatively efficiently. The snap mechanism, however, being disposed inside the hermetic vessel, is likely to accumulate foreign substances present in the fluids, such as dirt and scale, which will prevent smooth operation.
In view of the above-described problems inherent in the known prior art apparatus, it is an object of the present invention to provide a liquid forced-feed apparatus which operates smoothly.
The present invention is a liquid forced-feed apparatus provided with a hermetic vessel which has a working fluid inlet port, a working fluid discharge port, a forced-feed liquid inlet port, and a forced-feed liquid discharge port. Within the hermetic vessel is a float and a change-over valve and outside the hermetic vessel is a snap mechanism. The liquid forced-feed apparatus of the present invention is characterized by a power transmitting shaft which extends out of the hermetic vessel and transmits the up and down movement of the float to the snap mechanism. As the float moves up and down, the snap mechanism opens and closes the working fluid inlet port and working fluid discharge port, causing the liquid to be forced out of the hermetic vessel through the forced-feed liquid discharge port.
In the liquid forced-feed apparatus of the present invention, the shaft for transmitting the up and down movement of the float to the snap mechanism extends out of the hermetic vessel and the snap mechanism is disposed outside of the hermetic vessel. The snap mechanism can therefore operate without being affected by foreign substances in the hermetic vessel.
REFERENCES:
patent: Re. 34957 (1995-05-01), Francart, Jr.
patent: 1132942 (1915-03-01), Jay
patent: 1699464 (1929-01-01), Dutcher
patent: 3988786 (1976-11-01), Lehfeldt
patent: 4299248 (1981-11-01), Becker et al.
patent: 4436109 (1984-03-01), Taylor
patent: 5141405 (1992-08-01), Francart, Jr.
patent: 5211204 (1993-05-01), Mikol
patent: 5230361 (1993-07-01), Carr et al.
patent: 5265282 (1993-11-01), Schmucki
patent: 5426990 (1995-06-01), Francart, Jr.
patent: 5655888 (1997-08-01), Yumoto
patent: 5934881 (1999-08-01), Yumoto
patent: 5938409 (1999-08-01), Radle, Jr. et al.
patent: 5941691 (1999-08-01), Stephens
patent: 314 3284 (1983-05-01), None
patent: 715 046 (1996-06-01), None
patent: 1 389 045 (1975-04-01), None
patent: 127 5410 (1986-12-01), None
patent: 2012923 (1994-05-01), None
Brown Steven
Freay Charles G.
Kenyon & Kenyon
TLV Co. Ltd.
LandOfFree
Liquid forced-feed apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Liquid forced-feed apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Liquid forced-feed apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2475365