WO1998005587A1

WO1998005587A1 - Flow control system for dispensers

Info

Publication number: WO1998005587A1
Application number: PCT/US1997/014776
Authority: WO
Inventors: Alfred A. Schroeder
Original assignee: Lancer Partnership, Ltd.
Priority date: 1996-08-06
Filing date: 1997-08-06
Publication date: 1998-02-12
Also published as: AU4233697A

Abstract

A fluid flow control system (50) includes a body (120) having an inlet (193) communicating with a first outlet (153b) and a second outlet (153a) that provides unregulated fluid flow. A flow rate controller (200) resides within the body between the inlet and the first outlet to regulate the flow of fluid from the first outlet. The second outlet is sealable to provide only regulated fluid flow. Similarly, the inlet is sealable, and the second outlet is connectable to a fluid source (10) to permit regulated fluid flow from the second outlet to the first outlet. A screen (178) substantially housed within the body filters fluid entering the body from the inlet. An apparatus for dispensing fluids connects to the fluid flow control system and includes a tank (30) for storing fluid and a valve (20) between the first outlet and the tank for controlling fluid flow to the tank.

Description

FLOW CONTROL SYSTEM FOR DISPENSERS BACKGROUND OF THE INVENTION

1. Field of the Invention The present invention relates to dispensers, and more particularly, but not by way of limitation, to a flow control system for a dispenser.

2. Description of the Related Art

Certain dispensers release their beverages in batch quantities. One type that releases beverages in a batch quantity is a commercial coffee brewer that prepares individual pots of coffee. A commercial coffee brewer includes a large, heated water tank for releasing hot water into one or more coffee pots . To prepare a pot of coffee, a user activated controller opens a water tank inlet valve to release water into the tank. This water displaces a corresponding amount of water from the tank which enters a coffee pot through a siphon. The controller regulates the amount of water exiting the tank by opening the inlet valve for a preset amount of time. Once the preset time elapses, the controller shuts the inlet valve to stop the flow of water from the tank to the pot .

One problem associated with this control scheme is that inlet water pressure varies, resulting in varying amounts of water delivered to the coffee pot. Too little water results in a "short -pot", which is a pot of strong, bad-tasting coffee. Too much water may overflow the pot, thereby creating a mess and, possibly, a burn or slip hazard. One solution to minimize coffee pot fill fluctuations resulting from pressure swings utilizes a rubber flow washer. A semi-conical flow washer has a preset hole diameter in the unpressurized state. The flow washer's conical side is placed opposite to the water flow in the hot water tank's inlet line. Opening the inlet valve to the tank forces water from the water line toward the washer. The hardness of the rubber washer prevents flexing of the washer at low pressures. At higher pressures, however, the pressure forces the washer's conical side backwards, thereby constricting the size of the hole. The constricted hole at high pressures results in water flows that approximate the water flow rate exiting the larger, preset hole at low pressures. This washer control means attempts to provide a consistent metered amount of water for filling the coffee pot regardless of the water pressure.

Unfortunately, these rubber washer flow control systems suffer several disadvantages. The washers deteriorate from chemicals in the water and ultimately harden, which impedes their response to water pressure fluctuations. Additionally, lime or sediment in the water plugs the flow washer's orifice, thereby shorting the coffee pot of water. Due to these problems, service personnel must be called to inspect the washer when variations in water flow impact the quality of the coffee . A further disadvantage is that, even when the washers are operating properly, the coffee pot fill volume tends to fluctuate as much as 10 percent. For a 60 ounce target volume, this means that between 54 and 66 ounces of water may be released into the pot. Thus, even if the washer is performing optimally, too little water may be released into the pot creating coffee too strong or too much water may be released into the pot creating an overflow. Furthermore, washer flow control systems are limited to a pressure range of between 20 and 80 pounds per square inch. Moreover, these washers cannot be adjusted to increase or decrease the water flow rate. Additionally, the rubber washer flow control systems tend to be noisy, especially at high pressures. As the pressure constricts the orifice, water pushing through the orifice causes the washer to vibrate. The metal piping amplifies the vibration creating noise.

Accordingly, a flow control system for coffee dispensers that minimizes coffee pot fill volume fluctuations, improves serviceability, and reduces noise will improve over current flow control systems.

SUMMARY OF THE INVENTION In accordance with the present invention, a fluid flow control system includes a body having an inlet communicating with a first outlet and a second outlet that provides unregulated fluid flow. A flow rate controller resides within the body between the inlet and the first outlet to regulate the flow of fluid from the first outlet. The second outlet is sealable to provide only regulated fluid flow. Similarly, the inlet is sealable, and the second outlet is connectable to a fluid source to permit regulated fluid flow from the second outlet to the first outlet. A screen substantially housed within the body filters fluid entering the body from the inlet.

The flow rate controller includes a sleeve disposed within the body between the inlet and the first opening. The sleeve includes an aperture therethrough that communicates with the first outlet. The flow rate controller includes a piston disposed within the sleeve. The piston includes an aperture therethrough that communicates fluid to the aperture of the sleeve. The piston operates responsive to changes in fluid pressure to regulate the flow of fluid through the aperture of the sleeve. Specifically, increases in fluid pressure increasingly moves the piston over the aperture of the sleeve to retard fluid flow and, thus, maintain a constant flow rate. Decreases in fluid pressure decreasingly moves the piston away from the aperture of the sleeve to increase fluid flow and, thus, maintain the constant flow rate. The flow rate controller further includes a bonnet disposed within the body over the sleeve, a flow adjuster disposed within the bonnet, and a spring mounted between the flow adjuster and the piston to maintain the piston within the sleeve. An apparatus for dispensing fluids includes the above-described fluid flow control system with its inlet connected to a fluid source. The first outlet connects to a tank, and the second outlet connects to a coil disposed in the tank. A controller connected between the first outlet and the tank regulates when fluid is delivered to the tank. The tank includes either a heater or cooling system. The coil connects to a faucet used to control the delivery of fluid from the coil. It is, therefore, an object of the present invention to provide a flow control system for coffee brewers that improves operability.

Another object of the present invention is to provide a flow control system that minimizes coffee pot fill volume fluctuations.

A further object of the present invention is to provide a flow control system that can be retrofitted onto conventional coffee brewers.

A still further object of the present invention is to provide a flow control system for coffee brewers that improves serviceability.

Still other objects, features, and advantages of the present invention will become evident to those of ordinary skill in the art in light of the following. BRIEF DESCRIPTIONS OF THE DRAWINGS

Figure 1 is a schematic flow diagram illustrating the flow control system in a coffee brewer. Figure 2 is an exploded view illustrating the flow control system.

Figure 3 is side view in cross-section illustrating the flow control system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Figure 1 illustrates a flow control system or valve 50 utilized in a coffee brewer. To brew a pot of coffee, a user pushes a button 85. The pushing of the button 85 activates a controller 25 that opens a control valve 20, resulting in a pressure drop that releases water from an inlet water line 10. Simultaneously, a timer within the controller 25 activates for a preset amount of time to meter the open time for the control valve 20. Once the preset time expires, the controller 25 closes the control valve 20 to stop the water flow to a hot water tank 30.

Water flowing from the inlet water line 10 passes through the fluctuation dampening mechanism of the flow control system 50 and the control valve 20 and into the heated water tank 30. Water flowing from the control valve 20 displaces hot water within the tank 30 through a siphon near its top. The displaced water passes through coffee grounds held in a brew basket and into a coffee pot 80. Alternatively, hot water may be obtained through a faucet 60. The opening of the faucet 60 creates a pressure drop, that causes water to flow from the inlet water line 10 through the unregulated portion of the flow control system 50. The water travels into a coil 40 that is submerged in the heated water tank 30. The water exits the coil 40 into a faucet 60 where it may be released for capture in a container 90.

As illustrated in Figures 2 and 3, the flow control system 50 includes a body 120 having a base 122 formed integrally with a post 124. An outlet assembly 140 inserts into openings 134a-b, an inlet assembly 160 inserts into an inlet aperture 138, and a regulating mechanism 200 inserts into a passageway 126 of the post 124. The inlet assembly 160 includes a retainer 170, securing members 176a-b, a screen 178, 0-rings 180a-b, and an inlet adapter 190. Securing members 176a-b, preferably screws, attach the retainer 170 to the base 122. The retainer is pivotable about the securing member 176b to permit the placement of the screen 178 and the inlet adapter 190 into the base 122 of the body 120. The screen 178 filters the water entering the interior chamber 123 of the base 122 to prevent plugging of the regulating mechanism 200. In this preferred embodiment, the screen 178 is made from a stainless steel mesh. The inlet adapter 190 slides into the base 122 adjacent to the screen 178. Grooves 192a-b of the inlet adapter 190 receive O-rings 180a-b that provide a fluid seal to prevent leaks. To fasten the inlet adapter 190 to the body 120, the retainer 170 pivots about the screw 176b so that a U-shaped portion 172 of the retainer 170 inserts within a channel 191 of the inlet adapter 190. The outlet assembly 140 includes outlet adapters 150a-b, securing member 155, O-rings 157a-d, and retainer 158. The securing member 155, preferably a screw, inserts through a hole 159 in the retainer 158 and into a threaded cavity 135 in the body 120 to mount the retainer 158 to the body 120. The retainer 158 pivots about the screw 159 permitting the insertion of the stems 152a-b of the outlet adapters 150a-b into the openings 134a-b of the body 120. Each adapter 150a-b has two grooves 151a-d that receive a respective 0-ring 157a-d that provides a fluid seal to prevent leaks. To fasten the adapters 150a-b to the body 120, the retainer 158 is pivoted to place its hooked portions into the channels 154a-b of the output adapters 150a-b. The regulating mechanism 200 includes a sleeve 212, a piston 220, a spring 225, a bonnet 228, and a flow adjustment plug 235. The sleeve 212 and piston 220 are preferably made from a corrosion resistant material such as porcelain. A substantially circular groove 213 on the sleeve 212 receives an O-ring 210a that provides a fluid seal. In addition, the sleeve 212 has apertures 214a-f that permit fluid flow from the sleeve 212 (described herein) . The piston 220 includes an aperture 222 and is housed within the sleeve 212. The spring 225 biases the piston 220 against the flow of fluids. A protruding tip 239 of the flow adjustment plug 235 engages an end 226 of the spring 225. The plug 235 threadably mounts within the bonnet 228. Both the bonnet 228 and the plug 235 include a respective substantially circular groove 229 and 237 that receives an O-ring 210b and 234, respectively. Arms 230a-b reside within and are restrained by notches 130a-b of the post 124 of the body 120 to prevent rotation of the bonnet 228. Securing members 258a-b, preferably screws, mount within threaded cavities 128a-b of the post 124 to fasten the retainer 250 onto the passageway 126 of the post 124. The retainer 250 secures the bonnet 228 within the passageway 126, which, in turn, secures the flow adjustment plug 235, spring 225, piston 220, and sleeve 212.

In regulated operation, water enters the flow control system 50 through a passageway 193 in the inlet adapter 190 and flows into a chamber 123 of the base 122. After passing through an orifice 121 in the body 120, the water encounters the piston 220 of the regulating mechanism 200. At low pressures, water enters the piston 220 through the aperture 222, which is centered in the piston's lower face. The water passes unobstructed through apertures 214a-f of the sleeve 212 and exits through a passageway 153b of the outlet adapter 150b. At high pressures, the water not only enters the piston 220 via aperture 222, but also pushes against the lower face of the piston 220 to force the piston 220 upwards. As the piston 220 rises within the sleeve 212, its sides partially block the apertures 214a- f, thereby reducing the flow of water. The piston 220 retards the water flow at high pressures sufficiently to substantially match the flow rate when the apertures 214a- f remain fully open. Accordingly, the piston 220 ensures the flow rate of water through the sleeve 212 at high pressures substantially equals the water flow rate at low pressures. This regulating action maintains a constant flow rate regardless of fluctuations in water pressure to yield only a one percent variance over and under the desired coffee pot fill volume. Furthermore, the regulating mechanism 200 is operable at pressure ranging from 10 to 100 pounds per square inch. Additionally, the reciprocating action of the piston 220 within the sleeve 212 cleans the sleeve 212 by removing build-up or blockages from the apertures 214a-f. Moreover, the spring 225 acts to dampen vibrations caused by changes in water pressure. This dampening reduces the noise of the coffee brewer. Once water exits apertures 214a-f, it exits the flow control system 50 as previously described.

Alternatively for unregulated operation, such as turning on the faucet 60, water enters the passageway 193 of the inlet adapter 190 and flows into the chamber 123. From the chamber 123, it enters the passageway 153a of the adapter 150a prior to exiting the flow control system 50, thus bypassing the regulating mechanism 200. For coffee brewers not having a faucet 60, the adapter 150a can be replaced with a plug 250 that seals opening 134b. To increase or decrease flow rates, the flow adjustment plug 235 may be adjusted upwards or downwards utilizing a screwdriver. The lowering of the flow adjustment plug 235 increases the tension on the spring 225. Increasing the tension on the flow adjustment plug 235 increases the water pressure necessary to cause the piston 220 to raise and block the apertures 214a-f of the sleeve 212. Consequently, the flow rate increases because apertures 214a-f will be completely open or only partially blocked at higher pressures. The raising of the plug 235 lessens the tension on the spring 225. Decreasing the tension on the flow adjustment plug 235 decreases the water pressure necessary to cause the piston 220 to raise and block the sleeve apertures 214a-f. Consequently, the flow rate decreases because apertures 214a-f will be more fully blocked at lower pressures .

Claims

CLAIMS I claim:

1. A fluid flow control system, comprising: a body including an inlet communicating with first and second outlets; and a flow rate controller residing within said body between said inlet and said first outlet to regulate the flow of fluid from said first outlet.

2. The flow control system according to claim 1 further comprising a screen substantially housed within said body for filtering fluid entering said body from said inlet.

3. The flow control system according to claim 1, wherein the flow of fluid from said second outlet is unregulated.

4. The flow control system according to claim 1, wherein said second outlet is sealable to provide only regulated fluid flow.

5. The flow control system according to claim 1, wherein said inlet is sealable and said second outlet is connectable to a fluid source to permit regulated fluid flow from said second outlet to said first outlet.

6. The flow control system according to claim 1, wherein said flow rate controller, comprises: a sleeve disposed within said body between said inlet and said first opening, said sleeve including an aperture therethrough communicating with said first outlet ; a piston disposed within said sleeve and including an aperture therethrough that communicates fluid to said aperture of said sleeve wherein, responsive to changes in fluid pressure, said piston regulates the flow of fluid through said aperture of said sleeve to maintain a constant flow rate; and biasing means for maintaining said piston within said sleeve.

7. The flow control system according to claim 6, wherein increases in fluid pressure increasingly move said piston over said aperture of said sleeve to retard fluid flow and maintain the constant flow rate.

8. The flow control system according to claim 6, wherein said biasing means, responsive to decreases in fluid pressure, decreasingly moves said piston away from said aperture of said sleeve to increase fluid flow and maintain the constant flow rate.

9. The flow control system according to claim 6, wherein said biasing means, comprises: a bonnet disposed within said body over said sleeve ; a flow adjuster disposed within said bonnet; and a spring mounted between said flow adjuster and said piston to maintain said piston within said sleeve wherein adjustment of the position of said flow adjuster changes the tension of the spring.

10. An apparatus for dispensing fluids, comprising: a flow control valve, comprising: a body including an inlet connected to a fluid source, said inlet communicating with first and second outlets, and a flow rate controller residing within said body between said inlet and said first outlet to regulate the flow of fluid from said first outlet; a tank for storing said fluid; and means between said first outlet and said tank for controlling the delivery of fluid to said tank.

11. The apparatus for dispensing fluids according to claim 10, further comprising: a coil within said tank, said coil connected to said second outlet; and means for controlling the delivery of fluid from said coil .

12. The apparatus for dispensing fluids according to claim 10, wherein said tank includes means for heating said fluid.

13. The apparatus for dispensing fluids according to claim 10, wherein said tank includes means for cooling said fluid.

14. The apparatus for dispensing fluids according to claim 10, wherein said flow control valve comprises a screen substantially housed within said body for filtering fluid entering said body from said inlet.

15. The apparatus for dispensing fluids according to claim 10, wherein the flow of fluid from said second outlet of said flow control valve is unregulated.

16. The apparatus for dispensing fluids according to claim 10, wherein said second outlet of said flow control valve is sealable to provide only regulated fluid flow.

17. The apparatus for dispensing fluids according to claim 10, wherein said inlet is sealable and said second outlet is connectable to said fluid source to permit regulated fluid flow from said second outlet to said first outlet.

18. The apparatus for dispensing fluids according to claim 10, wherein said flow rate controller of said flow control valve, comprises: a sleeve disposed within said body between said inlet and said first opening, said sleeve including an aperture therethrough communicating with said first outlet ; a piston disposed within said sleeve and including an aperture therethrough that communicates fluid to said aperture of said sleeve wherein, responsive to changes in fluid pressure, said piston regulates the flow of fluid through said aperture of said sleeve to maintain a constant flow rate; and biasing means for maintaining said piston within said sleeve.

19. The apparatus for dispensing fluids according to claim 18, wherein increases in fluid pressure increasingly move said piston over said aperture of said sleeve to retard fluid flow and maintain the constant flow rate.

20. The apparatus for dispensing fluids according to claim 18, wherein said biasing means, responsive to decreases in fluid pressure, decreasingly moves said piston away from said aperture of said sleeve to increase fluid flow and maintain the constant flow rate.

21. The apparatus for dispensing fluids according to claim 18, wherein said biasing means, comprises: a bonnet disposed within said body over said sleeve; a flow adjuster disposed within said bonnet; and a spring mounted between said flow adjuster and said piston to maintain said piston within said sleeve wherein adjustment of the position of said flow adjuster changes the tension of the spring.