Coffee machine

• US 6,901,846 B2
• Filed: 03/04/2002
• Issued: 06/07/2005
• Est. Priority Date: 03/07/2001
• Status: Expired due to Fees

• Current Assignee: Etna Coffee Technologies B.V.
• Original Assignee: Etna Vending Technologies B.V. (ETNA Coffee Systems BV)
• Inventors: Ruckstuhl, Stephan
• Primary Examiner(s): Simone, Timothy F.
• Application Number:
  US10/471,002
• Publication Number:
  US 20040118296A1
• Time in Patent Office: 1,191 Days
• Field of Search: 995/16, 994/83, 99279-287 R, 992/93, 993/02.R, 992/95, 99297-307, 99452-455, 993/233
• US Class Current: 99/287
• CPC Class Codes: A47J 31/3614 Means to perform transfer from a loading position to an infusing position

Abstract

A coffee machine (10) comprises a removable brewing unit (18), in which ground coffee powder is compacted in a brewing chamber along a main axis of the brewing unit (18) between a movable lifting bottom and a plunger that can be displaced toward the lifting bottom. Pressurized hot water is pressed through the compacted coffee powder. Afterwards, the lifting bottom and plunger are displaced together along the main axis in order to push the remaining filter cake out of the brewing chamber whereby ejecting it transversal to the main axis. The aim of the invention is to provide a coffee machine of the aforementioned type with a simplified and space-saving design as well as with an easier accessibility for cleaning and maintenance purposes. To these ends, the brewing unit (18) is designed so that it can be pushed into the coffee machine (10) from the front towards the back with the main axis parallel to the direction of insertion.

Claims

1. Coffee machine (10) including a horizontally removable brewing unit (18) in which ground coffee powder is compacted along a main axis (48) of the brewing unit (18) between a movable base (28) and a plunger (32) that can be displaced towards the movable base (28) in a brewing chamber (29), pressurized hot water is forced through the compacted coffee powder, and the remaining filter cake is then pushed out of the brewing chamber (29) by displacement of the movable base (28) and of the plunger (32) together along the main axis (48), and is ejected transversely relative to the main axis (48), wherein the brewing unit (18) is adapted to be pushed into the coffee machine horizontally from the front towards the rear, with the main axis (48) parallel to the direction of insertion.

2. Coffee machine according to claim 1, wherein one or a plurality of guides (19) which extend parallel to the main axis (48) of the brewing unit and are bar-shaped are provided for guiding the brewing unit (18) during insertion in and removal from the coffee machine (10).

3. Coffee machine according to claim 2, wherein a catch (20) is provided at a front end of the guide (19) for locking the inserted brewing unit (18).

4. Coffee machine according to claim 1, wherein, in the brewing unit (18), the pressurized hot water is forced through the coffee powder disposed in the brewing chamber (29) in the direction of the main axis (48), forwards from the rear and leaves through an outlet (15) which is arranged at a front end of the brewing unit (18) and is adjustable in height.

5. Coffee machine according to claim 4, wherein the movable base (28) and the plunger (32) are equipped, on their surfaces facing the brewing chamber (29), with respective mesh plates (46, 47) through which the hot water enters the brewing chamber (29) and the brewed coffee leaves the brewing chamber (29), respectively.

6. Coffee machine according to claim 1, wherein the movable base (28) and the plunger (32) are driven by means of an actuating slide (27) which is arranged so as to be displaceable in the direction of the main axis (48) in the brewing unit (18) and which is releasably in engagement with a driving dog (25) which is situated on a threaded rod arranged parallel to the main axis (48) and which can be displaced along the main axis (48) by rotation of the threaded rod (21).

7. Coffee machine according to claim 6, wherein the releasable engagement between the driving dog (25) and the actuating slide (27) is brought about by means of a latching hook (26) which extends in the direction of the main axis (48) and is arranged so as to be pivotable on the driving dog (25) about a pivot axis arranged transversely relative to the main axis (48).

8. Coffee machine according to claim 6, wherein the threaded rod (21) is mounted so as to be displaceable in the direction of the main axis (48) against the pressure of a spring element, and the displacement of the threaded rod (21) against the pressure of the spring element for a predetermined travel, as established by the striking of the driving dog (25), of the actuating slide (27), or of the plunger (32), against a resistance, is used for the control or switching of the drive.

9. Coffee machine according to claim 1, wherein the plunger (32) is moved by means of a plunger actuator (33) displaceable in the direction of the main axis (48), and the plunger (32) is operatively connected to the plunger actuator (33) by means of compression springs (42, 43) acting in the direction of the main axis (48).

10. Coffee machine according to claim 9, wherein the pressurized hot water is supplied into the brewing chamber (29) through the plunger (32), and a valve mechanism (36, 37, 38, 39, 44, 45) is arranged on the plunger (32), the valve mechanism (36, 37, 38, 39, 44, 45) being closed when the plunger (32) presses on the coffee powder disposed in the brewing chamber with a predetermined pressure, and relieving the pressure of the pressurized water and allowing the water to escape to the exterior when the pressure of the plunger (32) on the coffee powder is removed.

11. Coffee machine according to claim 10, wherein the valve mechanism includes valve push-rods (36, 37) which are arranged on the plunger actuator (33) and which, upon sufficient compression of the compression springs (42, 43), sealingly enter corresponding valve bores (44, 45) in the plunger (32), which valve bores are in communication with a hot-water supply duct (34).

12. Coffee machine according to claim 11, wherein the hot-water supply duct (34) extends directly through one of the valve push-rods (36, 37), and the valve bores (44, 45) are in communication with the brewing chamber (29) through a mesh plate (46).