Manufacturing method and apparatus

The etching system of any preceding claim wherein the reservoir is formed from plastics material.

The etching system of any preceding claim further including means for controlling the temperature of the etchant.

The etching system of any preceding claim wherein the reservoir and etching head are integrally formed within a single cartridge unit.

The etching system of any preceding claim wherein the means for controllably ejecting etchant includes a means for applying pressure to the etchant to force it from the orifice.

The etching system of any preceding claim wherein the means for controllably ejecting etchant includes means for selectively charging droplets of etchant ejected from said orifice and means for controlling the the trajectory of charged droplets of etchant by the application of a variable electric field.

The etching system of any preceding claim wherein said etching head includes a controllable water inlet for introducing water at a controlled rate into an etchant stream flowing from said reservoir to said orifice, whereby the concentration of etchant ejected may be modified by modifying the rate at which water is introduced into the etchant stream.

The etching system of any preceding claim further comprising movement means for causing relative movement between the etching head and the etchable material.

The etching system of any preceding claim further including means for determining the shape or pattern of the etchable material and means for feeding this information back to the means for processing said design data for periodically adjusting the control signals for controlling the operation of the ejecting means to prevent large deviations away from the desired shape or pattern.

The etching system of any preceding claim including means for receiving billet data representative of the size and shape of the initial piece of etchable material, and wherein the processing means includes means for comparing the billet data with the design data in order to identify which portions of said initial piece of etchable material should be removed by etching in order to derive the item having the desired shape or pattern.

The etching system of any preceding claim wherein said processing means is operable to generate a negative shape or pattern from said design data which identifies the location of the or each portion to be removed.

The etching system of any preceding claim wherein the etching system is operable to form the desired shape or pattern by applying etchant to the etchable material in phases each of which removes etchable material to a predetermined depth.

The etching system of any preceding claim further including means for identifying a boundary between a portion of said etchable material, which is not to be removed by etching and a portion of said etchable material, which is to be removed by etching, and for controlling the etching system to deposit a different amount of etchant per volume of etchable material to be removed in the vicinity of said boundary compared to the amount of etchant per volume of etchable material to be removed deposited away from said boundary.

The etching system of any preceding claim further including vibrating means for causing said etchable material to vibrate whereby the speed with which newly deposited etchant comes into contact with unreacted etchable material to be etched is increased.

The etching system of any preceding claim wherein said system is operable to deposit etchant onto the surface of said etchable material at a rate which is greater than one tenth of a litre per square metre per minute.

An etching head cartridge having an etching head and reservoir of etchant, said etching head including one or more output orifices in fluid communication with said reservoir;

• means for receiving control signals;
• and means for controllably ejecting etchant out of the or each orifice in response to received control signals.

An etching apparatus comprising means for mounting an etching head and means for generating control signals for controlling the operation of said etching head, said etching apparatus including vibration means for vibrating a piece of etchable material while etchant is being deposited thereon.

An etching apparatus for use in an etching system for forming an item having a desired shape or pattern from an initial piece of etchable material, said etching apparatus comprising means for carrying an etching head mounted in an etching head carriage at least back and fourth along a scanning path relative to said etchable material and means for generating control signals for controlling the movement of the etching head carriage and for generating control signals for controlling the ejection of etchant droplets from said etching head, wherein said carrying means includes a guide rail and a bearing member for slidably attaching the etching head carriage to the guide rail, and wherein said guide rail and said bearing member are formed from a metal-etchant resistant material.

A host device for controlling an etching apparatus forming part of an etching system for forming an item having a desired shape or pattern from an initial piece of etchable material, said host device including means for receiving design data representative of the desired shape or pattern, means for identifying the location of the or each portion of said initial piece of material to be removed by etchant and means for generating data representative of the portions of said initial piece of etchant material to be removed by etching and expressing said representative data in terms of a number of volume elements in which volume elements within said portions to be removed by etching are designated as elements to be removed.

A method of forming an item having a desired shape or pattern from an initial piece of etchable material, said method comprising the steps of receiving design data representative of the desired shape or pattern;

• processing said design data (i) to identify the location of the or each portion of said initial piece of etchable material to be removed by etching, and (ii) from the or each identified location, generating control signals for controlling the operation of an etching head having an output orifice in communication with a supply of etchant and means for controllably ejecting etchant out of the orifice onto the etchable material in response to the control signals;
• and applying said generated control signals to said ejecting means in order to selectively eject etchant from said orifice onto said initial piece of etchable material to form said item with the desired shape or pattern.

The method of any preceding claim including the step of selectively charging droplets of etchant ejected from said orifice and controlling the charged droplets of etchant by the application of a variable electric field.

A method of ejecting etchant from an etching head comprising the steps of receiving one or more control signals and ejecting droplets of etchant in response to the control signals.

A method of operating an etching apparatus comprising the steps of receiving etching data;

• and
• generating control signals from said etching data for driving an etching head to selectively deposit droplets of etchant onto a piece of etchable material in accordance with the etching data.

The method of either one of claims 78 or 79 including detecting the distance from a distance sensor mounted on the etching apparatus to a predetermined location or locations on the piece of etchable material to be etched and using this information to control the movement of the etching head.

A method of controlling an etching apparatus forming part of an etching system for forming an item of a desired shape or pattern from an initial piece of etchable material, said method including receiving design data representative of the desired shape or pattern, identifying the location of the or each portion of said initial piece of material to be removed by etchant and generating data representative of the portions of said initial piece of etchant material to be removed by etching and expressing said representative data in terms of a number of volume elements in which volume elements within said portion to be removed by etching are designated as elements to be removed.

A method of forming a wanted item from an initial piece of etchable material, said method comprising the step of:

• selectively depositing etchant onto unwanted portions of the initial piece of etchable material, whereby said unwanted portions are removed to generate said wanted item.