CA2051093A1 - Electric discharge machine with multiple tool electrodes - Google Patents
Electric discharge machine with multiple tool electrodesInfo
- Publication number
- CA2051093A1 CA2051093A1 CA 2051093 CA2051093A CA2051093A1 CA 2051093 A1 CA2051093 A1 CA 2051093A1 CA 2051093 CA2051093 CA 2051093 CA 2051093 A CA2051093 A CA 2051093A CA 2051093 A1 CA2051093 A1 CA 2051093A1
- Authority
- CA
- Canada
- Prior art keywords
- electric discharge
- tool electrodes
- power supply
- discharge machine
- workpieces
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H1/00—Electrical discharge machining, i.e. removing metal with a series of rapidly recurring electrical discharges between an electrode and a workpiece in the presence of a fluid dielectric
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
Abstract
ELECTRIC DISCHARGE MACHINE WITH
MULTIPLE TOOL ELECTRODES
ABSTRACT OF THE DISCLOSURE
An electric discharge machine for simultaneously machining a plurality of workpieces includes a main machine assembly having a movable ram member, an electrode clamping assembly carried by the movable ram member, a plurality of tool electrodes secured to the electrode clamping assembly, and a workbench. Each of the workpieces is secured on the workbench immediately below one of the tool electrodes. A power supply box supplies discharge current independently to each of the tool electrodes.
MULTIPLE TOOL ELECTRODES
ABSTRACT OF THE DISCLOSURE
An electric discharge machine for simultaneously machining a plurality of workpieces includes a main machine assembly having a movable ram member, an electrode clamping assembly carried by the movable ram member, a plurality of tool electrodes secured to the electrode clamping assembly, and a workbench. Each of the workpieces is secured on the workbench immediately below one of the tool electrodes. A power supply box supplies discharge current independently to each of the tool electrodes.
Description
ELECTRIC DISCHARGE MACHINE WITH
MULTIPLE TOOL ELECTRODES
BACKGROUND OF THE INVENTION
1. Field of the Invention The invention relates to an electric discharge machine, more particularly to an electric discharge machine incorporating multiple tool electrodes.
MULTIPLE TOOL ELECTRODES
BACKGROUND OF THE INVENTION
1. Field of the Invention The invention relates to an electric discharge machine, more particularly to an electric discharge machine incorporating multiple tool electrodes.
2. Description of the Related Art Electric discharge (or electric-spark) machining is a metal removal process in which materials that conduct electricity are removed by electric sparks. Machining of a stationary workpiece is accomplished without any grinding or cutting operation so that the workpiece is not subjected to external forces which may cause undesired deformation thereto. Electric discharge machines possess a high degree of precision and can be used for relatively long periods. These machines are preferred if accurate machining is desired.
Figure 1 is an illustration of a conventional electric discharge machine. The electric discharge machine comprises two major parts: a main machine assembly (90) and a power supply box (80). Normally, the main machine assembly (90) is fitted with a movable ram (11), an electrode clamping tool (12) carried by the movable ram (11), and a tool electrode (13) coaxially secured to the electrode clamping tool (12).
The metal workpiece (14) is provided immediately below the tool electrode (13) and is held in a stationary position by a magnetic base (15) of a workbench on the main machine assembly (90). The movable ram (11) is drivingly coupled to a servomechanism (not shown). As material removal progresses, the movable ram (11) advances the tool electrode (13) toward the workpiece (14) to maintain a constant spark gap. The discharge current can be controlled via the power supply box (80).
During use, the desired depth of material removal is first set. When machining has reached the set depth, current to the servomechanism is cut-off and machining of the workpiece (14) is stopped. An alarm signal is then generated to indicate that machining has been accomplished. The workpiece (14) is then removed and replaced with a new workpiece.
The main machine assembly (90) also includes various operating circuits and control keys, and a lighting and dielectric fluid supply system. The power supply box (80) contains the necessary power supply control and detector circuits, and several control keys.
Figure 2 illustrates the electrical connection between the power supply box (80) and the main machine assembly (90). Electrical wires (801) transmit power and control signals from the power supply box (80) to the main machine assembly (90). Electrical wires (802) transmit the required discharge current from the power 205109:~
supply box (80) to the tool electrode (13) and to the workpiece (14). The power supply box (80) has an electrical plug (803) for connection with a primary AC
electrical outlet.
The conventional electric discharge machine has the following characteristics and limitations:
1. The tool electrode and the workpiece are spaced by a small spark gap. The spark generated melts the small point on the surface of the workpiece that it strikes and forms a crater thereat. This is how the electric discharge machine achieves its machining objective.
2. The surface of the workpiece is gradually eroded through the use of this method and excessive amounts of current tend to roughen the surface of the workpiece.
Therefore, in order to obtain a high degree of accuracy, machining of the workpiece must be accomplished at a very slow pace.
Figure 1 is an illustration of a conventional electric discharge machine. The electric discharge machine comprises two major parts: a main machine assembly (90) and a power supply box (80). Normally, the main machine assembly (90) is fitted with a movable ram (11), an electrode clamping tool (12) carried by the movable ram (11), and a tool electrode (13) coaxially secured to the electrode clamping tool (12).
The metal workpiece (14) is provided immediately below the tool electrode (13) and is held in a stationary position by a magnetic base (15) of a workbench on the main machine assembly (90). The movable ram (11) is drivingly coupled to a servomechanism (not shown). As material removal progresses, the movable ram (11) advances the tool electrode (13) toward the workpiece (14) to maintain a constant spark gap. The discharge current can be controlled via the power supply box (80).
During use, the desired depth of material removal is first set. When machining has reached the set depth, current to the servomechanism is cut-off and machining of the workpiece (14) is stopped. An alarm signal is then generated to indicate that machining has been accomplished. The workpiece (14) is then removed and replaced with a new workpiece.
The main machine assembly (90) also includes various operating circuits and control keys, and a lighting and dielectric fluid supply system. The power supply box (80) contains the necessary power supply control and detector circuits, and several control keys.
Figure 2 illustrates the electrical connection between the power supply box (80) and the main machine assembly (90). Electrical wires (801) transmit power and control signals from the power supply box (80) to the main machine assembly (90). Electrical wires (802) transmit the required discharge current from the power 205109:~
supply box (80) to the tool electrode (13) and to the workpiece (14). The power supply box (80) has an electrical plug (803) for connection with a primary AC
electrical outlet.
The conventional electric discharge machine has the following characteristics and limitations:
1. The tool electrode and the workpiece are spaced by a small spark gap. The spark generated melts the small point on the surface of the workpiece that it strikes and forms a crater thereat. This is how the electric discharge machine achieves its machining objective.
2. The surface of the workpiece is gradually eroded through the use of this method and excessive amounts of current tend to roughen the surface of the workpiece.
Therefore, in order to obtain a high degree of accuracy, machining of the workpiece must be accomplished at a very slow pace.
3. Since the desired depth of material removal is set beforehand, manual supervision is unnecessary during machining. When machining has been accomplished, the electric discharge machine automatically stops and an alarm signal is then generated to indicate that the machined workpiece can be removed and replaced with a new workpiece.
4. The conventional electric discharge machine can machine only a single workpiece at a time. Machining a Z05~09~
batch of workpieces thus requires a long total machining time. To reduce the total machining time, additional electric discharge machines must be provided. This solution is, however, quite costly.
SUMMARY OF THE INVENTION
The main objective of the present invention is to provide an electric discharge machine having multiple tool electrodes to permit simultaneous machining of a plurality of workpieces, thereby reducing total machining time without entailing high equipment costs.
Accordingly, the preferred embodiment of an electric discharge machine of the present invention comprises: a main machine assembly including a movable ram member, an electrode clamping assembly carried by the movable ram member, a plurality of tool electrodes secured to the electrode clamping assembly, and a workbench, each of the workpieces being secured on the workbench immediately below one of the tool electrodes; and a power supply box including a discharge current supplying means to supply discharge current independently to each of the tool electrodes. The discharge current supplying means can be formed as a plurality of electrode sockets provided on the power supply box or as a plurality of independent power supply devices. The present invention thus provides an electric discharge machine having a plurality of tool electrodes in a single main machine assembly to permit Z05109~
simultaneous machining of a plurality of similar or different workpieces to reduce the total machining time without incurring huge equipment costs.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:
Figure 1 is an illustration of a conventional electric discharge machine;
Figure 2 illustrates the electrical connection between a main machine assembly and a power supply box of the conventional electric discharge machine shown in Figure 1;
Figure 3 is an illustra-tion of the preferred embodiment of an electric discharge machine with multiple tool electrodes according to the present invention;
Figure 4 is a first example of electrical connection between a main machine assembly and a power supply box of the electric discharge machine shown in Figure 3;
and Figure 5 is a second example of electrical connection between the main machine assembly and a power supply box of the electric discharge machine shown in Figure 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
20S109~
Referring to Figures 3 and 4, the first preferred embodiment of an electric discharge machine with multiple tool electrodes according to the present invention is shown to comprise a main machine assembly (91) and a power supply box (81). The main machine assembly (91) is fitted with a movable ram (11'), an electrode clamping assembly (12') carried by the movable ram (11') and tool electrodes (131-134) secured to the electrode clamping assembly (12'). [Figure 3 shows four tool electrodes (131-134) secured to the electrode clamping assembly (12'), although more may be provided thereon depending upon the construction of the electrode clamping assembly (12')]. Metal workpieces (141-144) are each disposed immediately below a respective one of the tool electrodes (131-134) and are provided on a workbench (15') of the main machine assembly (91). The movable ram (11') is drivingly coupled to a servomechanism (not shown).
Electrical wires (801') transmit power and control signals from the power supply box (81) to the main machine assembly (91). The power supply box (81) is provided with a plurality of electrode discharge current supply sockets ~811-818). Four of the sockets, (811-814), are electrically connected to the tool 2S electrodes (131-134). [The remaining sockets (815-818) are provided to supply discharge current to additional tool electrodes]. The electrode sockets (811-814) 205~09:~
supply the required discharge current from the power supply box (81) to the tool electrodes (131-134) and to the workpieces (141-144). The power supply box (81) further has an electrical plug (803') for connection with a primary AC electrical outlet.
The spark gaps between the tool electrodes (131-134) and the respective workpieces (141-144) are preferably equal, so that machining of the workpieces (141-144) can be accomplished at an equal pace. Equal machining pace is desirable especially if the wor~pieces are of the same type, and the desired machining is the same for all workpieces.
The preferred embodiment can also be used even if the specifications of the workpieces are different, such as different machining depths are required.
Assuming that depths of 0.05 mm and 0.03 mm are required, those workpieces which require a machining depth of 0.05 mm are first machined up to a depth of 0.02 mm. Machining of all the workpieces is then performed at an equal pace for the remaining depth of 0.03 mm. Machining of all the workpieces thus ends at roughly the same time, and the electric discharge machine generates an alarm signal to indicate that the machined workpieces can be removed and replaced with a new set of workpieces.
Figure 5 is a second preferred embodiment of an electric discharge machine with multiple tool ~05~09.~
electrodes according to the present invention.
Electrical wires (801") are provided to transmit power and control signals from a power supply box (82) to the main machine assembly (91) of the electric discharge machine. The operation of the second preferred embodiment is substantially similar to that of the first preferred embodiment and will not be detailed further~ The main difference between the first and second preferred embodiments lies in the construction of the power supply boxes, (81) and (82). The power supply box (82) comprises a plurality of independent power supplies (821-826). Each of the independent power supplies (821-826) has an electrical plug (804-809) for connection with a primary AC electrical outlet. Four of the power supplies, (821-824), are electrically connected to the tool electrodes (131-134) and the workpieces (141-144), supplying the required discharge current. The remaining power supplies (825-826) are not connected to the tool electrodes (131-134) but instead supply the required power to drive the servomechanism and other parts of the main machine assembly (91).
The present invention thus provides an electric discharge machine which has a plurality of tool electrodes in a single main machine assembly. This permits simultaneous machining of a plurality of similar or different workpieces. This is in contrast with conventional electric discharge machines which .ZOSlQ9:~
permit machining of only one workpiece at a time.
While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments, but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
batch of workpieces thus requires a long total machining time. To reduce the total machining time, additional electric discharge machines must be provided. This solution is, however, quite costly.
SUMMARY OF THE INVENTION
The main objective of the present invention is to provide an electric discharge machine having multiple tool electrodes to permit simultaneous machining of a plurality of workpieces, thereby reducing total machining time without entailing high equipment costs.
Accordingly, the preferred embodiment of an electric discharge machine of the present invention comprises: a main machine assembly including a movable ram member, an electrode clamping assembly carried by the movable ram member, a plurality of tool electrodes secured to the electrode clamping assembly, and a workbench, each of the workpieces being secured on the workbench immediately below one of the tool electrodes; and a power supply box including a discharge current supplying means to supply discharge current independently to each of the tool electrodes. The discharge current supplying means can be formed as a plurality of electrode sockets provided on the power supply box or as a plurality of independent power supply devices. The present invention thus provides an electric discharge machine having a plurality of tool electrodes in a single main machine assembly to permit Z05109~
simultaneous machining of a plurality of similar or different workpieces to reduce the total machining time without incurring huge equipment costs.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:
Figure 1 is an illustration of a conventional electric discharge machine;
Figure 2 illustrates the electrical connection between a main machine assembly and a power supply box of the conventional electric discharge machine shown in Figure 1;
Figure 3 is an illustra-tion of the preferred embodiment of an electric discharge machine with multiple tool electrodes according to the present invention;
Figure 4 is a first example of electrical connection between a main machine assembly and a power supply box of the electric discharge machine shown in Figure 3;
and Figure 5 is a second example of electrical connection between the main machine assembly and a power supply box of the electric discharge machine shown in Figure 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
20S109~
Referring to Figures 3 and 4, the first preferred embodiment of an electric discharge machine with multiple tool electrodes according to the present invention is shown to comprise a main machine assembly (91) and a power supply box (81). The main machine assembly (91) is fitted with a movable ram (11'), an electrode clamping assembly (12') carried by the movable ram (11') and tool electrodes (131-134) secured to the electrode clamping assembly (12'). [Figure 3 shows four tool electrodes (131-134) secured to the electrode clamping assembly (12'), although more may be provided thereon depending upon the construction of the electrode clamping assembly (12')]. Metal workpieces (141-144) are each disposed immediately below a respective one of the tool electrodes (131-134) and are provided on a workbench (15') of the main machine assembly (91). The movable ram (11') is drivingly coupled to a servomechanism (not shown).
Electrical wires (801') transmit power and control signals from the power supply box (81) to the main machine assembly (91). The power supply box (81) is provided with a plurality of electrode discharge current supply sockets ~811-818). Four of the sockets, (811-814), are electrically connected to the tool 2S electrodes (131-134). [The remaining sockets (815-818) are provided to supply discharge current to additional tool electrodes]. The electrode sockets (811-814) 205~09:~
supply the required discharge current from the power supply box (81) to the tool electrodes (131-134) and to the workpieces (141-144). The power supply box (81) further has an electrical plug (803') for connection with a primary AC electrical outlet.
The spark gaps between the tool electrodes (131-134) and the respective workpieces (141-144) are preferably equal, so that machining of the workpieces (141-144) can be accomplished at an equal pace. Equal machining pace is desirable especially if the wor~pieces are of the same type, and the desired machining is the same for all workpieces.
The preferred embodiment can also be used even if the specifications of the workpieces are different, such as different machining depths are required.
Assuming that depths of 0.05 mm and 0.03 mm are required, those workpieces which require a machining depth of 0.05 mm are first machined up to a depth of 0.02 mm. Machining of all the workpieces is then performed at an equal pace for the remaining depth of 0.03 mm. Machining of all the workpieces thus ends at roughly the same time, and the electric discharge machine generates an alarm signal to indicate that the machined workpieces can be removed and replaced with a new set of workpieces.
Figure 5 is a second preferred embodiment of an electric discharge machine with multiple tool ~05~09.~
electrodes according to the present invention.
Electrical wires (801") are provided to transmit power and control signals from a power supply box (82) to the main machine assembly (91) of the electric discharge machine. The operation of the second preferred embodiment is substantially similar to that of the first preferred embodiment and will not be detailed further~ The main difference between the first and second preferred embodiments lies in the construction of the power supply boxes, (81) and (82). The power supply box (82) comprises a plurality of independent power supplies (821-826). Each of the independent power supplies (821-826) has an electrical plug (804-809) for connection with a primary AC electrical outlet. Four of the power supplies, (821-824), are electrically connected to the tool electrodes (131-134) and the workpieces (141-144), supplying the required discharge current. The remaining power supplies (825-826) are not connected to the tool electrodes (131-134) but instead supply the required power to drive the servomechanism and other parts of the main machine assembly (91).
The present invention thus provides an electric discharge machine which has a plurality of tool electrodes in a single main machine assembly. This permits simultaneous machining of a plurality of similar or different workpieces. This is in contrast with conventional electric discharge machines which .ZOSlQ9:~
permit machining of only one workpiece at a time.
While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments, but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
Claims (5)
1. An electric discharge machine for simultaneously machining a plurality of workpieces, comprising:
a main machine assembly including a movable ram member, an electrode clamping assembly carried by said movable ram member, a plurality of tool electrodes secured to said electrode clamping assembly, and a workbench, each of said workpieces being secured on said workbench immediately below one of said tool electrodes; and a power supply box including a discharge current supplying means to supply discharge current independently to each of said tool electrodes.
a main machine assembly including a movable ram member, an electrode clamping assembly carried by said movable ram member, a plurality of tool electrodes secured to said electrode clamping assembly, and a workbench, each of said workpieces being secured on said workbench immediately below one of said tool electrodes; and a power supply box including a discharge current supplying means to supply discharge current independently to each of said tool electrodes.
2. The electric discharge machine as claimed in claim 1, wherein said discharge current supplying means comprises a plurality of electrode sockets provided on said power supply box, each of said tool electrodes being electrically connected to one of said electrode sockets.
3. The electric discharge machine as claimed in claim 1, wherein said discharge current supplying means comprises a plurality of independent power supply devices, each of said tool electrodes being connected to one of said power supply devices.
4. The electric discharge machine as claimed in claim 2, wherein said power supply box includes an electrical plug for connection with a primary AC electrical outlet.
5. The electric discharge machine as claimed in claim 3, wherein each of said independent power devices has an electrical plug for connection with a primary AC
electrical outlet.
electrical outlet.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEG9013255.6 | 1990-09-19 | ||
| DE9013255U DE9013255U1 (en) | 1990-09-19 | 1990-09-19 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2051093A1 true CA2051093A1 (en) | 1992-03-20 |
Family
ID=6857639
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2051093 Abandoned CA2051093A1 (en) | 1990-09-19 | 1991-09-10 | Electric discharge machine with multiple tool electrodes |
Country Status (4)
| Country | Link |
|---|---|
| CA (1) | CA2051093A1 (en) |
| CH (1) | CH683971A5 (en) |
| DE (1) | DE9013255U1 (en) |
| GB (1) | GB2248032A (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19622918A1 (en) * | 1996-06-07 | 1997-12-11 | Fraunhofer Ges Forschung | Tool electrode and installation for spark-erosive machining |
| US5847350A (en) * | 1997-06-16 | 1998-12-08 | General Electric Company | Adjustable mount |
| US6373018B1 (en) * | 2000-02-07 | 2002-04-16 | General Electric Company | Apparatus and method for electrical discharge machining multiple holes |
| US6563071B2 (en) * | 2001-05-15 | 2003-05-13 | General Electric Company | Method and apparatus for electrical discharge machining with multiple workstations |
| US9550245B2 (en) * | 2008-07-24 | 2017-01-24 | Mitsubishi Electric Corporation | Electric discharge machining apparatus, electric discharge machining method, and semiconductor substrate manufacturing method |
| CN108705166B (en) * | 2018-06-25 | 2020-03-31 | 宁波工程学院 | Convertible operating platform for numerical control electric spark machine tool |
| CN108746891B (en) * | 2018-06-25 | 2020-02-18 | 宁波工程学院 | Convertible manufacturing technology table for electric spark machine tool |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4320278A (en) * | 1979-03-26 | 1982-03-16 | Colt Industries Operating Corp | Servo feed system for electrical discharge machining apparatus |
| US4242560A (en) * | 1979-03-26 | 1980-12-30 | Colt Industries Operating Corp. | Servo feed system for an electrical discharge machining apparatus |
| US4441004A (en) * | 1980-06-12 | 1984-04-03 | Inoue-Japax Research Incorporated | Multiple pipe element electrode assembly EDM method and apparatus |
-
1990
- 1990-09-19 DE DE9013255U patent/DE9013255U1/de not_active Expired - Lifetime
-
1991
- 1991-07-16 GB GB9115329A patent/GB2248032A/en not_active Withdrawn
- 1991-09-10 CA CA 2051093 patent/CA2051093A1/en not_active Abandoned
- 1991-09-18 CH CH275591A patent/CH683971A5/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| CH683971A5 (en) | 1994-06-30 |
| GB9115329D0 (en) | 1991-08-28 |
| DE9013255U1 (en) | 1991-02-14 |
| GB2248032A (en) | 1992-03-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Dead |