US2975723A

US2975723A - Percolator pump construction

Info

Publication number: US2975723A
Application number: US696983A
Authority: US
Inventors: Theodore E Andrews
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1957-11-18
Filing date: 1957-11-18
Publication date: 1961-03-21
Anticipated expiration: 1978-03-21

Description

March 2l, 1961 TQ E. ANDREWS PERCoLAToR PUMP CONSTRUCTION Filed NOV. 18. 1957 PW f@ a@ 4mm@ for pumping liquid during operation thereof.

PERCOLATOR PUMP CONSTRUCTION Theodore E. Andrews, `Oreield, Pa., assignor to' General Electric Company, a corporation of New York Filed Nov. 18, 1957, Ser. No. 696,983

V Claims. (Cl. 10S-231.5)

The instant invention relates generally to percolators, and particularly to an improvement in the means for pumping yliquid in percolators during their operation.

As is well known, percolators are widely used in American homes to brew coffee, particularly during the early morning at breakfast time. When so used, it is extremely desirable that the percolator brew colfee in the quickest and quietest manner. The time required to brew coifee is largely dependent upon the efficiency, that is, the pumping rate, of the means in the pecolator for pumping liquid during operation thereof. The amount of noise made by a percolator is also largely dependent upon the construction of the means in the percolator Most people have been vexed in the difficult hectic morning hours by having to wait for coifee to brew and/or by being disturbed by having to listen to a noisy percolator brewing coffee. The percolator art has recognized the seriousness of the problems of: (1) lack of speed, and (2) presence of noise in existing percolators, and as a result, much effort has been directed toward eliminating them. For example, in my copending patent application, Serial No. 675,959, entitled Percolator Pump Construction, led August 2, 1957, and assigned to the assignee of the instant application, I have disclosed and claimed inter alia an improved percolator having improved liquid pumping means which is both efficient and quiet in operation, and therefore, which is eminently well suited to eliminate the problems of lack of speed and presence of noise in previously existing percolators.

It is an object of this invention to provide an improved percolator that includes improved liquid pumping means which is both elicient and quiet in operation, but which differs structurally and operationally from the percolator pump construction disclosed and claimed in my referredto copending patent application.

It is another object of my invention to eliminate the problems of lack of speed and presence of noise in existing percolator pump constructions of the general type dis- Vclosed in-U.S. Patent No. 1,922,546 (Fig. 3), which type of pump construction is widely used in practice.

VThe objects of this invention are achieved inone form by` the provision, in a percolator having a pump well, of a pump assembly whichy includes an elongated pump vltube that has an apertured pump body fixed to it near its lower end, a pump washer that is movably mounted on the pump tube adjacent to the pump body and is adapted during operation to periodically close the apertures in the pump body in a mannerwhich is known to the percolator art, and a one-way valve that operates in the'pump tube at a point spaced above the location of the pump body. Y

The above and' other objects and further details of that which I believe to be novel and my invention will be clear from the following description and claims taken with the accompanying drawing wherein:

Fig. 1 is a side elevational view, with portions broken away and shown in section for the sake of clarity, of a ted States Patent O ice l 2 percolator which incorporates the improved pump construction;

Fig. 2 is a fragmentary vertical sectional view of the pump construction shown in Fig. 1 on an enlarged scale;

Fig. 3 is a fragmentary perspective view of the pump tube showing the ball check valve construction;

Fig. 4 is a fragmentary vertical sectional view taken through a portion of the pump tube which includes the ball check valve construction, and illustrating the parts during operation of the percolator when liquid is owing vupwardly through the pump tube;

Fig. 5 is a schematic view of a currently widely used, prior art pump construction showing the parts during operation thereof;

Fig. 6 is a schematic view of the improved pump coni struction showing the parts at the time during operation thereof when liquid is flowing upwardly through the pump tube;

Fig. 7 is a view similar to Fig. 6, but showing the parts after most of the liquid in the pump well has been pumped up out of the pump well, and the pressure in the pump well has been reduced below that of the head of liquid in the percolator reservoir, and l Fig. 8 is a View similar to Fig. 7, but showing the parts shortly after the pump well has been refilled with liquid from the reservoir andthe liquid in the pump well has been heated and started to be pumped up through the pump tube. f

By reference to the drawing, and' particularly Fig. 1, it will be seen that the improved pump construction may be incorporated in a percolator such as the one indicated generally by the reference character P, which includes the body 10, the spout 12, the handle 14, the base 16, and the lid 18. Within the percolator there is formed a liquid reservoir 20 which is defined by a major portion of a percolator body, the lid and an interior, horizontal, bottom wall 22. It will be understood that notwithstandting the fact that the illustrated percolator is one of the automatic electric type, this being the preferred type, that the improved pump construction can be utilized in any'percolator and does not necessarily have to be used in an electric or automatic one.

The illustrated percolator includes a pump well 24 which depends below the bottom wall 22. The 'pumpwell is formed by pump well cup 26 which comprises circular well bottom wall 28, cylindrical well side Walls 30 and an annular mounting flange 32. Bottom wall 22 has an opening 34 formed therein which is adapted to receive the pump well cup 26, which may be secured to the wall 22 in any known way. Pump heater member .36 imay be secured to the pump well cup l(26 in any known manner, and when energized functions to heat the well 24. It will be understood that the connection between the pump well cup, the bottom wall and the pump heater member will be sealed appropriately to prevent liquid from leaking out of the reservoir 20.

The pump heater member 36 includes a heater 38, which may be of the widely used, sheathed electrical resistance type, which is embedded in the member. The construction of the percolator and the pump will be described thus far is well known, as is the practice of utilizing with such construction a pump assembly comprising a vertically extending pump tube, such as illustrated pump tube 40, which supports a removable cotfee basket, such as the illustrated 'coffee basket 42, near its upper end, and a rigidly mounted, disk-like pump end wall and associated movable pump washer, such as the illustrated

parts

44 and 46, respectively, near its lower end.

garajes known; as pointed out above, this type of percolator pump is generally disclosed in the referred-to Patent No. 1,922,546 (Fig. 3). It has been found in practice that percolators including this type of pump construction: (l) operate in a noisy manner which is characterized by a periodic loud thumping noise, and (2) do not have an entirely satisfactory pumping rate. lt has also been found in practice that the addition iof a one-way valve in the pump tube of the known pump construction substantially eliminates the objectionable thumping noise inherent in the known constructions and increases the pumping rate appreciably, thereby reducing the amount of time required to brew coffee.

It will be observed in Fig. 2 that the referred-to, disklike pump end wall 44 includes the dished portion 48 and the central flat portion 50, which has a plurality of spaced openings 52 formed therein. It A'will also be observed that the pump end wall 44 is rigidly connected to the pump tube 40 between and by the annular bead 54 formed on the pump tube and the hub S6 of the collar 58, which in turn is rigidly mounted on the pump tube by the flared end 60 of the pump tube. It will also be observed that the pump washer 46 is mounted on the exterior of the hub S6 of the collar 5S so as to be freely slidable thereon between the limits xed by the ange 62 of said collar, and the circular bosses 64 formed on the lower side of the iiat portion S of the pump body which surround the openings 52.

It will be observed in Fig. l that the pump assembly is adapted to be temporarily lremovably positioned in the -percolator body in such a manner that circumferential portions of the outer surface of the dished portion 48 of the pump end -wall 44 rest on the circular valve seat 66 formed in the general vicinity of the intersection of the cylindrical well side walls 30 and the ange 32 of the pump Well cup 26. When mounted in this manner, the pump well 24 becomes a pumping chamber which is adapted to periodically communicate with the reservoir 20 through the openings 52 during operation `of the percolator, all in a known manner.

The operation of the pump construction described thus far is well known and briey comprises (with reference to Fig. 5, which is a schematic illustration of a prior art ipump) the admission of liquid from the reservoir PR through the openings PO in the pump body PB past the pump washer WP and into the pump well PW, where it is heated by the heater PH, and on sufficient heating, the liquid in the pump well vaporizes, pressure builds up within the pump well, and finally the pump washer is moved upwardly to close the openings PO and liquid is pumped up through the tube PT. After a sufficient amount of liquid has been pumped up the tube PT, the pressure within the pump well PW is reduced below that of the head of the liquid in the reservoir PR, and this results in: (l) the washer WP being forced downwardly and liquid entering the pump well, and (2) liquid in the pump tube falling downwardly back into the pump well. It is at this stage of the operation that the schematic illustration of Fig. 5 indicates the positions of the various parts. It will there be noted that at the same time liquid is entering into the pump well, after a previous charge has been pumped up through the pump tube PT, that a slug of liquid PS exists in the pump tube which falls back into the pump well PW by gravity and by atmospheric pressure, which becomes operative due to the reduction of pressure in the pump well below atmospheric pressure as cooler water entering from the reservoir PR condenses the remaining vapor in the pump well. The upper level of this slug of liquid is generally indicated by the line PL in Fig. 5. It will be readily understood that the pumping rate of the pump is reduced by this action, for it requires that a certain amount of liquid be repumped up the tube PT before it is actually pumped out the top of the tube into the coffee basket. It is believed that the action just described is'also responsible 4 i for the excessive noise in prior art pump constructions, because it is believed that the falling slug PS of liquid makes a thumping noise when it contacts the bottom of the pump well or newly admitted cooler liquid in the pump well.

In order to eliminate 4the two defects of the prior art percolator pump constructions pointed out above, the instant invention utilizes a one-way valve which is mounted in the pump tube 40 at a point above the lower end thereof. The one-way valve construction is best illustrated in Figs. 2, 3 and 4;*it will there be seen that it comprises the annular valve seat 68, which may be formed by a radially inwardly extending bead that is formed in the pump tube; the valve member 70, which may be in the form of a ball, and the valve stop 72, which may be in the form of a pin that is secured within the pump tube in any convenient manner at a point spaced above the valve seat 63.

Prior to operation `of the percolator, the parts of the improved pump construction are disposed as illustrated in Fig. 2. The ball valve member 70 rests on the valve seat 68, and the pump washer 46 rests on the flange 62 of the collar 58, both as a result of the force of gravity. Prior to operation, the reservoir 2G is charged with liquid, which normally is water, and the basket 4-2 is filled with the material to be brewed, which normally is ground coffee. Liquid iiows from the reservoir 20, through the openings 52, past the pump washer 46 and into the pump well 24. To operate, the heater 38 is energized, and this results in heating the liquid in the pump well. On sutiicient heating, the liquid in the pump well vaporizes and pressure is built up in the pump well 24; the pressure causes: (l) the pump washer 46 to be moved upwardly against the bosses 64, to thereby close the openings 52, and (2) steam and liquid to be forced up through the pump tube 40. When the liquid reaches the ball valve member 70 it moves it upwardly off the valve seat 68 and passes by it up to and over the top of the pump tube; Fig. 4 illustrates this condition of the valve parts, and it will there be seen that the ball valve member 70 has been moved to its uppermost limit, in which it contacts the stop 72. A schematic illustration of the parts of the improved pump at this time is shown in Fig. 6, where it will be observed that: (l) the pump washer 46 is in its upper position in which it closes the openings 52 in the pump end wall 44, (2') the ball valve member 70 is in its upper position in which it contacts stop 72, and (3) steam and liquid is flowing upwardly through the pump tube 40.

After substantially all of the liquid in the pump Well 24 has been pumped Vup into the pump tube 40, the pressure in the pump well is reduced and two effects result: (l) the pump washer 46 is forced downwardly by the head of the liquid in the reservoir 20, and (2) the liquid in the pump tube 40 falls downwardly by the forceof gravity and effect of atmospheric pressure. This condition is illustrated schematically in Fig. 7, where it will be observed that when this occurs, the ball valve member 70 is rapidly moved to its lowermost position, in which it contacts the valve seat 68 and thereby closes the valve and prevents any of the liquid in the pump tube 40 above it from falling downwardly back into the pump well 24.

After the pump well 24 is completely lled with liquid and heated sufficiently, the liquid in the pump well vaporizes, builds up pressure, moves the pump washer 46 upwardly to its closed position and pumps liquid up through the pump tube 40. In Fig. 8, there is schematically illustrated the condition of the parts immediately after-pumping of the next charge occurs, and it will there be .seen that very little liquid need be pumped up through the pump tube 40 until the ball valve member 70 -is unseated. It will, therefore, be apparent'that the pumping of liquid is substantially continuous, 'and therefore, the pumping rate ism'aintained at a maximum. It

and the newly admited liquid and the pump well in the prior art device is eliminated, and therefore, the excessive noiseassociated with the prior art pump is substantially eliminated.

As will be evident from the foregoing description, certain aspects of my invention are not limited to the particular details of construction of the example illustrated, and I contemplate that various and other modiiications and applications will occur to those skilled in the art. It is, therefore, my intention that the appended claims shall cover such modiiications and applications as do not depart from the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. A percolator comprising: a liquid reservoir, a pump well defined by heat conducting walls located below said reservoir; said pump well having an opening placing said reservoir and said pump well in communication with each other; said heat conducting Walls being constructed and arranged to receive heat from a heat source adjacent the bottom of said reservoir; an elongated pump tube; a

` pump and wall rigidly secured to said pump tube near an end thereof; said pump tube and said pump end wall adapted to be jointly removably mounted in said reservoir with said pump end wall temporarily substantially closing said opening, said pump end wall having apertures therein for placing said reservoir in limited communication with said pump well, a pump washer slidably mounted on said pump tube adjacent to said pump end wall and adapted during operation to periodically close the apertures in said pump end wall to thereby periodically disrupt communication between said reservoir and said pump well; whereby during operation of said percolator, small amounts of cold liquid from said reservoir periodically ow through the apertures in saidy pump end wall into said pump well where they are heated by said heating means and pumped up through said pump tube, and a one-way valve disposed in the lower portion of said pump tube and adapted to allow liquid to ilow only upwardly through said pump tube, whereby during operation of said percolator said valve operates to prevent any liquid which is in said pump tube above said valve from returning to said pump well, thereby improving the liquid iiow rate through said pump tube and minimizing noise caused during operation.

2. A device as defined in claim 1 -wherein said one-way Valve comprises an upwardly 4facing annular valve seat, a ball valve member in said pump tube above said valve seat and adapted during operation to periodically contact said valve seat to thereby periodically close said valve and prevent liquid in said pump tube above said valve seat from moving downwardly through said pump tube, and a stop which is spaced above said valve seat, projects into said pump tube and is adapted to limit the upward movement of said ball valve member during operation of the percolator.

3. A device as defined in claim 2 wherein said valve seat is formed by a constriction in said pump tube.

4. A device as defined in claim 3 wherein said stop is formed by a pin that is supported by said pump tube.

5. A device as defined in claim 2 wherein said stop is kformed by a pin that is supported by said pump tube.

References Cited in the tile of this patent UNITED STATES PATENTS Re. 22,879 Peters er al May 13, 1947 1,175,619 Dewey Mar. 14, 1916 1,609,524 Y Marchesseault Dec. 7, 19,26 1,831,384 Grometstein Nov. 10, 1931 1,921,748 Grometstein Aug. 8, 1933 1,922,546 Lucia Aug. 15, 1933 Y FOREIGN PATENTS 229,883 Germany Ian. 10, 1911 255,370 Switzerland June 30, 1948 451,675 Italy Sept. 23, 1949