WO1990014774A1

WO1990014774A1 - Easily cleanable steam wand

Info

Publication number: WO1990014774A1
Application number: PCT/US1990/003270
Authority: WO
Inventors: Howard W. Selby, Iii
Original assignee: Selsys Corporation
Priority date: 1989-06-09
Filing date: 1990-06-08
Publication date: 1990-12-13
Also published as: AU5822590A

Abstract

An espresso coffee machine (10) having a steam wand (12) that is used for steaming liquids such as milk for espresso coffee drinks, the steam wand having a nostick, polytetrafluoroethylene, outer surface (14) from which residue from the steamed liquid can be easily cleaned.

Description

Easily Cleanable Steam Wand

Technical Field

This invention relates to espresso coffee machines, and specifically to steam wands that are used on such machines.

Background Art

Steam wands that are provided on conventional espresso coffee machines are usually used to steam a quantity of milk. The steamed milk is then used in a variety of espresso coffee drinks. The steam wand is immersed in a pitcher of milk, and operates to introduce steam into the milk, thereby heating and foaming the milk. On conventional espresso machines the steam wand is made of metal, and normally has an outer surface that is chrome plated. Due to the high temperature that the steam wand achieves during the steaming process, and due to the interaction between the metal steam wand and the hot milk, the milk adheres to the outer surface of the wand as a crusty residue that is difficult to remove.

It would be desirable to have a steam wand with a no-stick outer surface that can be easily cleaned of milk residue.

Disclosure of the Invention

In view of the foregoing, it is an object of this invention to provide a steam wand having a no-stick material coated on the outer metal surface of the wand, the no-stick material being easily cleaned.

These and other objects of the invention are accomplished in accordance with the invention by coating the outer metal surface of a conventional steam wand with a relatively thin layer of no-stick material such as polytetrafluoroethylene, the brand Teflon. The no-stick portion of the steam wand is immersed in the liquid being heated by the steam wand. Once the steaming process is complete, the steam wand can be easily cleaned by wiping its outer no-stick surface with a cloth or a sponge.

As features of the invention, this layer of no-stick material may be coated onto the outer surface of the metal wand, or it may be provided as a relatively flexible sleeve of no-stick material that is slipped over the major length of a metal steam wand.

As a further feature of the invention, the steam wand may comprise a top metal portion that is threaded into the top of a relatively rigid and elongated block of no-stick material, and into the top of a central bore in the elongated block through which the steam passes on its way to a metal tip that is threaded into the lower end of the elongated block. With this construction and arrangement, the centrally located no-stick block portion of the wand remains relatively cool, thus providing for easier handling by the operator.

Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawing and the following detailed description of the invention.

Brief Description of the Drawings

FIG. 1 is a perspective view of a portion of an espresso coffee machine showing a steam wand having a no-stick outer surface.

Detailed Description of the Invention

Referring now to the drawing, there is shown in FIG. 1 a portion of an espresso coffee machine 10 having a steam wand 12, the outer surface of the steam wand being coated with a no-stick material 14. In a preferred embodiment of the invention the no-stick material is a synthetic polytetrafluoroethylene polymer or resin, for example the brand Teflon. No-stick material is coated onto the outer surface of wand 14, to a conventional thickness, using a conventional coating process, as is well known to those of skill in the art.

No-stick coating 14 does not cover the lower end steam emitting end of wand 12. Thus the coating does not interfere with the steaming operation of wand 12. There is no criticality to the placement of the no-stick coating on the metal wand, other than the coating must not interfere with operation of the steam head that is located at the lower end of the wand.

No-stick material coating 14 is located on the outer surface of metal steam wand 12, and covers at least the lower portion of the steam wand, i.e. that portion of the wand that will be immersed in the liquid to be heated.

In an embodiment of the invention, the layer of no-stick material shown in FIG. 1 comprises a relatively flexible sleeve 14 of no-stick material that is slipped over the major length of a steam wand 12. This construction and arrangement facilitates retrofitting of existing espresso coffee machines, for example.

In yet another embodiment of the invention, the steam wand of FIG. 1 may comprise a top metal portion 12 that is threaded into the top of a relatively rigid and elongated block 14 of no-stick material. This block of material is provided with a generally vertically extending central bore through which steam passes on its way to the wand's bottom disposed metal tip or steam head. This metal tip is threaded into the lower end of elongated block 14, so as to be in communication with the lower end of the steam bore. With this construction and arrangement, the centrally located no-stick block portion 14 of the wand remains relatively cool, thus providing for easier handling an operator.

Claims

1. An espresso coffee machine having a generally vertically elongated steam wand having a lower end adapted for immersion in a quantity of milk to be steamed, and a no-stick material affixed to the outer surface of said steam wand and extending upward from the lower end thereof so as to cover at least the portion of said steam wand that is to be immersed in milk.

2. The steam wand of claim 1 wherein said steam wand is metal and wherein said no-stick material is polytetrafluoroethylene.

3. The steam wand of claim 2 wherein said no-stick material comprises a sleeve that is slipped over said metal steam wand.

4. An espresso coffee machine having a generally vertically elongated steam wand having a lower end adapted for immersion in a quantity of milk to be steamed, comprising; a generally vertically elongated block of no-stick material having a generally vertically extending steam bore therein, a metal steam pipe threaded into the upper end of said steam bore, and a metal steam head threaded into the lower end of said steam bore.

5. The steam wand of claim 4 wherein said elongated block is formed of polytetrafluoroethylene.

6. An method of providing an espresso machine having an easily cleanable steam wand, comprising the steps of providing a vertically elongated metal steam wand adapted for immersion in a quantity of milk to be steamed, and providing no-stick material affixed to the outer surface of said steam wand and extending upward from the lower end thereof, so as to cover at least the lower portion of said steam wand that is to be immersed in milk.

7. The method of claim 6 wherein said no-stick material is polytetrafluoroethylene.