Coffee machine

• US 6,382,083 B2
• Filed: 02/28/2001
• Issued: 05/07/2002
• Est. Priority Date: 03/15/2000
• Status: Expired due to Term

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Fianara International BV (Koninklijke Philips N.V.)
• Inventors: Schmed, Arthur
• Primary Examiner(s): Alexander, Reginald L.
• Application Number:
  US09/795,755
• Publication Number:
  US 20010022138A1
• Time in Patent Office: 433 Days
• Field of Search: 992/83, 992/99, 993/02.R, 992/95, 992/89.R, 992/92, 993/07
• US Class Current: 99/289.00R
• CPC Class Codes: A47J 31/0605 with a valve at the filter-outlet; Anti-drip devices A47J31/0615, A47J31/0621 take precedence
• CPC Class Codes: A47J 31/36 with mechanical pressure-producing means
• CPC Class Codes: A47J 31/4496 Means to produce beverage with a layer on top, e.g. of cream, foam or froth
• CPC Class Codes: A47J 31/461 Valves, e.g. drain valves

Abstract

The invention refers to a coffee machine having a brewing chamber and a beverage outlet. A valve assembly is inserted between the brewing chamber and the beverage outlet. The valve assembly comprises a valve seat and a valve body member movable with regard to the valve seat. The valve body member is biased by a spring and can be moved, against the force of the spring, by the pressure of the coffee beverage flowing through the valve assembly. Moreover, these are provided for adjusting the bias force of the spring. In such a design, the operator or user of the coffee machine can directly influence the amount of coffee to be brewed per time unit. Moreover, within the limits of the user selected value, the brewing water flows through the coffee powder received in the brewing chamber with an essentially constant flow rate, regardless the amount and granule size of the coffee powder received in the brewing chamber.

Claims

1. A coffee machine, comprising:

a fresh water supply means;

a coffee brewing unit means provided with a brewing chamber means;

means for supplying coffee powder to said brewing chamber means;

a coffee beverage outlet means;

a pump means for conveying water under pressure from said fresh water supply means through said brewing chamber means containing said coffee powder to said coffee beverage outlet means; and

a valve means inserted between said brewing chamber means and said coffee beverage outlet means, said valve means comprising means for adjusting the amount of coffee beverage flowing through said valve means per time unit.

2. A coffee machine according to claim 1 in which said valve means comprises:

a valve chamber means and a valve body member means movable in said valve chamber means from an open position in which said coffee beverage means can flow through said valve means to a closed position in which the flow of said coffee beverage means through said valve means is blocked; and

a spring means acting on said valve body member means to bias said valve body member means to move into said open position, said valve body member means having surface means exposed to said coffee beverage means flowing into said valve means;

said valve body member means being adapted to be moved, against said biasing force exerted by said spring means, into said closed position when said surface means are charged by the pressure of said coffee beverage.

3. A coffee machine according to claim 2 in which said valve means comprises means for adjusting the bias force exerted by said spring means on said valve body member means.

4. A coffee machine according to claim 2 in which said valve chamber means of said valve means comprises:

an inlet means and an outlet means;

a valve seat means cooperating with said valve body member means and located at said inlet means; and

means for varying the flow cross sectional area of said inlet means and/or said outlet means.

5. A coffee machine according to claim 2 in which said outlet means comprises a bore means having a predetermined cross sectional area, and in which said valve body member means comprises a base portion, said base portion being provided with said surface means exposed to said coffee beverage means flowing into said valve means.

6. A coffee machine according to claim 2 in which said valve body member means comprises a shaft member means and a head portion means located at the free end of said shaft member means, said head portion means being provided with a control surface means facing said valve seat means and having a shape essentially corresponding to the shape of said valve seat means.

7. A coffee machine according to claim 2 in which said valve seat means comprises a central opening of conical shape.

8. A coffee machine according to claim 2 in which said valve body member means is of a one-piece construction, and in which said valve seat means is constituted by an insert member means made of an elastic material.

9. A coffee machine according to claim 2 in which a passage is provided between said control surface means of said valve body member means and said valve seat means when said valve body member means is in said spring biased open position.

10. A coffee machine according to claim 2 in which said valve body member means is movable, opposite to the bias force exerted by said spring means, to such an extent that said control surface means of said valve body member means closes said opening provided in said valve seat means.

11. A coffee machine according to claim 2 in which said biasing force exerted by said spring means is manually adjustable or adjustable by an electric motor means, by an electromagnet means, by a pneumatic means or by a hydraulic means.

12. A coffee machine according to claim 4 in which said means for varying the flow cross sectional area of said inlet means and/or said outlet means are manually operable or operable by an electric motor means, by an electromagnet means, by a pneumatic means or by a hydraulic means.

13. A coffee machine according to claim 5 in which the outlet end of said bore means having a predetermined cross sectional area is provided with a needle valve means for varying the flow cross section of said valve chamber means.

14. A coffee machine according to claim 1 in which said means for adjusting the amount of coffee beverage flowing through said valve means per time unit includes an adjustment screw means or a rotary adjustment knob means.

15. A coffee machine according to claim 3 in which said means for adjusting the bias force exerted by said spring means on said valve body member means include an adjustment screw means or a rotary adjustment knob means.

16. A coffee machine according to claim 14, further comprising means for keeping said rotary adjustment knob means in a selected position.

17. A coffee machine according to claim 2 in which said valve means comprises a posterior chamber means, whereby said base portion of said valve body member means is provided at its side facing said posterior chamber means with a recess means for receiving and supporting said spring means.

18. A coffee machine according to claim 17 in which said valve means further comprises a diaphragm means for sealing said valve chamber means from said posterior chamber means.

19. A coffee machine according to claim 6 in which said diaphragm means comprises a central aperture means through which said shaft member means extends.

20. A coffee machine according to claim 2 in which said valve means comprises a housing means consisting of several housing portions, said diaphragm means being fixed between two of said several housing portions.

21. A coffee machine according to claim 1, comprising means for automatically adjusting the amount of coffee beverage flowing through said valve means per time unit in dependence on the kind of coffee beverage to be prepared.

22. A coffee machine according to claim 3, comprising means for adjusting the bias force exerted by said spring means on said valve body member means in dependence on the kind of coffee beverage to be prepared.

23. A valve assembly for a coffee machine according to claim 1, comprising:

means for adjusting the amount of coffee beverage flowing through said valve assembly per time unit, whereby said valve assembly comprises a valve means designed as a mechanically operating regulating valve having a spring biased valve body member means, said valve body member means being kept in an open position by said spring bias force and being movable to its closed position, opposite to the spring bias force, under the influence of the pressurized coffee beverage flowing there through.

24. A coffee machine, comprising:

a brewing water supply means;

a coffee brewing unit means provided with a brewing chamber means;

means for supplying coffee powder to said brewing chamber means;

a coffee beverage outlet means;

a pump means for conveying brewing water under pressure from said brewing water supply means through said brewing chamber means containing said coffee powder to said coffee beverage outlet means; and

a valve means inserted between said brewing chamber means and said coffee beverage outlet means, said valve means being designed as a mechanically operating regulating valve having a flow passage with a variable cross sectional area, said valve means comprising means for adjusting the cross sectional area of said flow passage in response to the flow resistance presented to the brewing water flowing through said brewing chamber by the coffee powder contained in said brewing chamber such that the flow rate of the brewing water flowing through said coffee powder contained in said brewing chamber is kept essentially constant.