EDM Method and apparatus with the controlled supply of a liquid machining medium into the gap

Claim 1

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid medium to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed from the workpiece, said amount in volume per unit weight of stock removed ranging between 400 and 3000 cc/gr; and presetting the rate of flow of said liquid machining medium replenished into discharge sites of said machining gap in conjunction with at least one of the parameters of said electrical discharges determining the prescribed stock removal by weight per unit time, thereby presetting said amount in volume per unit weight.

Claim 2

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid medium to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed from the workpiece, said amount in volume per unit weight of stock removed ranging between 400 and 3000 cc/gr; and presetting the rate of flow of said liquid machining medium replenished into discharge sites of said machining gap in conjunction with at least one of the parameters of said electrical discharges determining the prescribed stock removal by weight per unit time, thereby presetting said amount in volume per unit weight.

Claim 3

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid medium to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed from the workpiece, said amount in volume per unit weight of stock removed ranging between 400 and 3000 cc/gr; and sensing at least one variable parameter of said electrical discharges determining the variable stock removal by weight per unit time to provide an output signal and, in response to said output signal, controlling the rate of flow of said liquid machining medium replenished into discharge sites of said machining gap in such a manner that said amount in volume per unit weight is maintained.

Claim 4

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid medium to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed from the workpiece, said amount in volume per unit weight of stock removed ranging between 400 and 3000 cc/gr; and sensing at least one variable parameter of said electrical discharges determining the variable stock removal by weight per unit time to provide an output signal and, in response to said output signal, controlling the rate of flow of said liquid machining medium replenished into discharge sites of said machining gap in such a manner that said amount in volume per unit weight is maintained.

Claim 9

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed from the workpiece, said amount in volume per unit weight of stock removed ranging between 400 and 3000 cc/gr; and controlling the rate of flow of said liquid machining medium replenished into discharge sites of said machining gap as a function of the depth of a cavity progressively machined in said workpiece in conjunction with the prescribed stock removal by weight per unit time.

Claim 10

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed from the workpiece, said amount in volume per unit weight of stock removed ranging between 400 and 3000 cc/gr; and controlling the rate of flow of said liquid machining medium replenished into discharge sites of said machining gap as a function of the depth of a cavity progressively machined in said workpiece in conjunction with the prescribed stock removal by weight per unit time.

Claim 11

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid medium to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed ranging between 400 and 3000 cc/gr, and imparting to said tool electrode vibrations of a frequency of 1 kHz to 10 MHz to facilitate passage of said liquid machining medium into and through said machining gap.

Claim 12

A method of machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising the steps of: supplying a liquid machining medium into said gap; effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid medium to produce such electrical discharges consecutively, and predetermining said amount in volume for each unit weight of said stock removed ranging between 400 and 3000 cc/gr, and imparting to said tool electrode vibrations of a frequency of 1 kHz to 10 MHz to facilitate passage of said liquid machining medium into and through said machining gap.

Claim 22

An apparatus for machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising: liquid supply means for supplying a liquid machining medium into said machining gap; power supply means for effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium into the machining gap being progressively contaminated with discharge products; first setting means associated with said power supply means for presetting parameters of said electrical discharges; and flow regulation means operable to act on said liquid supply means for replenishing a predetermined amount in volume of said liquid machining into discharge sites of said machining gap to partially replace said contaminated liquid to produce such electrical discharges consecutively, said amount in volume being predetermined for each unit weight of said stock removal from the workpiece and ranging between 400 and 3000 cc/gr, said flow regulation means including second setting means associated with said first setting means for presetting the rate of flow of said liquid machining medium to be replenished into discharge sites of said machining gap in conjunction with at least one of said presettable parameters of the electrical discharges determining the prescribed stock removal by weight per unit time, thereby presetting said amount in volume per unit weight said flow regulation means also including means responsive to at least one variable parameter of said electrical discharges for modifying said rate of flow.

Claim 23

An apparatus for machining an electrically conductive workpiece with a tool electrode spacedly juxtaposed therewith across a machining gap, comprising: liquid supply means for supplying a liquid machining medium into said machining gap; power supply means for effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium into the machining gap being progressively contaminated with discharge products; first setting means associated with said power supply means for presetting parameters of said electrical discharges; and flow regulation means operable to act on said liquid supply means for replenishing a predetermined amount in volume of said liquid machining into discharge sites of said machining gap to partially replace said contaminated liquid to produce such electrical discharges consecutively, said amount in volume being predetermined for each unit weight of said stock removal from the workpiece and ranging between 400 and 3000 cc/gr, said flow regulation means including second setting means associated with said first setting means for presetting the rate of flow of said liquid machining medium to be replenished into discharge sites of said machining gap in conjunction with at least one of said presettable parameters of the electrical discharges determining the prescribed stock removal by weight per unit time, thereby presetting said amount in volume per unit weight said flow regulation means also including means responsive to at least one variable parameter of said electrical discharges for modifying said rate of flow.

Claim 24

An apparatus for machining an electrically conductive workpiece with a tool elelctrode spacedly juxtaposed therewith across a machining gap, comprising: liquid supply means for supplying a liquid machining medium into said machining gap; power supply means for effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; and flow regulation means operable to act on said liquid supply means for replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid to produce such electrical discharges consecutively, said amount in volume being predetermined for each unit weight of said stock removal from the workpiece and ranging between 400 and 3000 cc gr, said flow regulation means including means responsive to said machining gap for sensing at least one variable parameter of said electrical discharges determining the variable stock removal by weight per unit time and thereby controlling the rate of flow of said liquid machining medium replenished into discharge sites in said machining gap in such a manner that said amount in volume per unit weight is maintained.

Claim 25

An apparatus for machining an electrically conductive workpiece with a tool elelctrode spacedly juxtaposed therewith across a machining gap, comprising: liquid supply means for supplying a liquid machining medium into said machining gap; power supply means for effecting a succession of electrical discharges between the tool electrode and the workpiece to electroerosively remove stock from the workpiece with said liquid medium in the machining gap being progressively contaminated with discharge products; and flow regulation means operable to act on said liquid supply means for replenishing a predetermined amount in volume of said liquid machining medium into discharge sites of said machining gap to partially replace said contaminated liquid to produce such electrical discharges consecutively, said amount in volume being predetermined for each unit weight of said stock removal from the workpiece and ranging between 400 and 3000 cc gr, said flow regulation means including means responsive to said machining gap for sensing at least one variable parameter of said electrical discharges determining the variable stock removal by weight per unit time and thereby controlling the rate of flow of said liquid machining medium replenished into discharge sites in said machining gap in such a manner that said amount in volume per unit weight is maintained.