DESCRIPTION
WELDING MACHINE
TECHNICAL FIELD
The present invention relates to devices for processing workpieces to be processed with, for example, arc generation; particularly, relates to a welding machine that performs welding work on digital control.
BACKGROUND ART
In recent years, as devices enhance its performance and functionality, control circuits of a welding machine, such as an electric-power control circuit, a gas control circuit, and a start control circuit, are formed of programmable elements. Such structured welding machines are generally controlled by software and they have been increasingly popular as digital control welding machines (hereinafter, referred to as digital welding machines).
A digital welding machine provides a variety of welding methods, and for each method, detailed welding conditions can be defined. In the welding methods, for example, a DC welding mode provides DC output to a workpiece of iron or stainless steel, and an AC output mode provides AC output to a workpiece of aluminum. Further, a pulse welding method provides output of pulse waveform according to the condition of a workpiece. For setting detailed welding conditions, it is necessary for a welding operator to change an output current, a pulse frequency, and a pulse width, with use of enormous amounts of condition parameters, according to thickness of a workpiece, welding positions, and the like.
A digital welding machine contains an encoder that is generally called a

jog dial, an LED display, and many switches for setting welding conditions. Welding operators determine the parameters on their knowledge and experience with reference to working conditions in an instruction manual.
Besides, in an arc welding machine of a recent model, a text display section such as a liquid crystal display is disposed in the operating section. In such an arc welding machine equipped with the display, instructions shown on the display enables a welding operator to set welding conditions suitable for the workpiece to be processed and the welding position. The arc welding machine has the function of setting parameters for a welding method and welding current suitable for the welding' conditions. Such structured arc welding machine allows an operator to easily set desired welding conditions even if the operator does not have much knowledge about welding (see patent literature 1, for example).
Hereinafter, the structure of a conventional welding machine is described with reference to Fig. 14. Fig. 14 is a plan view showing a general structure of the operating section of a conventional welding machine.
As shown in Fig. 14, the arc welding machine has LED display section 21 for showing alphanumeric characters, liquid crystal display 22 for showing text data, jog dial 23 for setting welding conditions, and switch section 24 for setting welding conditions.
The workings of such structured conventional arc welding machine will be described below.
The operator selects an item of welding conditions by operating switch section 24 and sets a value for the selected item by operating jog dial 23. Each time the operator sets a value, the value is shown on LED display section 21, by which the operator can confirm it. The operator repeats the operation until the welding conditions needed for the intended welding operation are

completely set, and then starts the welding work.
In a welding machine equipped with a guide function of welding conditions, the operator selects a mode of guiding welding conditions by operating switch section 24. In response to the operation, liquid crystal display 22 changes the display into a state of setting welding conditions, for example, of a workpieces. The operator determines each item of welding conditions while operating jog dial 23 and switch section 24. Receiving the data input by the operator, the welding machine finally shows welding conditions corresponding to the setting in LED display section 21.
However, such a conventional arc welding machine—where an operator selects desired welding conditions from many items on welding conditions—needs many parameters for setting welding conditions. To cope with a large number of parameters, the conventional structure has the need for having a liquid crystal display and a plurality of switches for setting welding conditions, increasing the production cost. [Citation List] [Patent Literature] [PTLl] Japanese Unexamined Patent Application Publication No. 2010-201499
SUMMARY OF THE INVENTION
The present invention provides a simply-structured, inexpensive welding machine that enables an operator—even if the operator is on an entry level of welding work—to easily set optimum welding conditions.'
To address the aforementioned problem, the welding machine of the present invention has a function' with which a welding operator selects a plurality of items on welding information to determine welding conditions.

The welding machine has a display section, an information section, a switching section, and a determining section. In the structure above, welding information is selected by operation of the switching section and the determining section. The display section has a plurality of LEDs each of which having a plurality of segments. The information section is positioned so as to correspond to each segment. The information section displays welding information indicated by a segment in a light-on state. The switching section switches the welding information of the information section by switching the light-on segment. In response to operation by the operator while the segment is keeping the light-on state, the determining section determines the welding information corresponding to the light-on segment.
With the structure above, the operator can set welding information by only operating the switching section and the determining section while viewing the LED display section. That is, optimum welding conditions can be easily obtained. The structure allows an operator to set welding conditions easily even if the operator does not have much knowledge about the welding conditions.
Besides, the structure with no need for a liquid crystal display and many switches for setting welding conditions contributes to a simply-structured operating section, decreasing the cost and time for producing the welding machine.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view showing the appearance of the welding machine in accordance with a first exemplary embodiment of the present invention.
Fig. 2 is a block diagram showing a general structure of the welding

machine in accordance with the first exemplary embodiment of the present invention.
Fig. 3 is a plan view showing a general structure of the operating section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 4 is a plan view showing a general structure of the operating section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 5 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 6 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 7 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 8 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 9 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 10 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 11 is a plan view showing- a display example of the display section of

the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 12 is a plan view showing a display example of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 13A is a plan view showing a display example of the LED of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 13B is a plan view showing a display example of the LED of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 13C is a plan view showing a display example of the LED of the display section of the welding machine in accordance with the first exemplary embodiment of the present invention.
Fig. 14 is a plan view showing a general structure of the operating section of a conventional welding machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, an exemplary embodiment of the present invention will be described with reference to accompanying drawings. In the drawings below, like components have the same reference marks and the descriptions thereof may be omitted. FIRST EXEMPLARY EMBODIMENT
Welding machine 1 of the present invention is described with reference to Fig. 1 through Fig. 13. Fig. 1 is a perspective view showing the appearance of welding machine 1 in accordance with the first exemplary embodiment. Fig. 2 is a block diagram showing a general structure of welding machine 1 in

accordance with the first exemplary embodiment. Each of Fig. 3 and Fig. 4 is a plan view showing a general structure of operating section 2 of welding machine 1 in accordance with the first exemplary embodiment. Fig. 5 through Fig. 12 and Fig. 13A through Fig. 13C are plan views, each of which shows a display example of LED display section 3 as an example of the display section of welding machine 1 of the first exemplary embodiment.
As shown in Fig. 1 and Fig. 2, welding machine 1 has operating section 2.
As shown in Fig. 2, operating section 2 has LED display section 3, switching section 4, determining section 5, and mode setting section 6. LED display section 3 displays various information items: Switching section 4 changes display items shown in LED display section 3. Determining section 5 determines the information items shown in LED display section 3. Mode setting section 6 sets a mode including a welding-condition setting mode. As shown in Fig. 2, welding machine 1 contains first storage 7, second storage 8, third storage 9, and fourth storage 10, which will be described later. Further, welding machine 1 has controller 11 for controlling the components of welding machine 1, such as LED display section 3, switching section 4, and determining section 5.
It will be understood that welding machine 1 needs a transformer as a component necessary for welding work; however, it has no direct bearing on the technical features described in the first exemplary embodiment, and therefore, such a component is omitted in Fig. 2.
Next, operating section 2 of welding machine 1 of the first exemplary embodiment will be described. Operating section 2 is conceptually illustrated with reference to Fig. 3 showing a plan view of a general structure of operating section 2. At the same time, operating section 2 is specifically illustrated with reference to Fig. 4 showing another plan view of a general structure of

operating section 2.
As shown in Fig. 3, operating section 2 has LED display section 3 having a plurality of LEDs each of which having a plurality of segments for displaying alphanumeric characters, switching section 4 for switching the display of LED display section 3, determining section 5, and mode setting section 6. LED display section 3 contains a plurality of LEDs 3a so as to form first LED display section Al, second LED display section A2, and third LED display section A3. Each of sections Al, A2, and A3 has a plurality of segments.
In operating section 2, information section 14 is disposed at positions that hold LED display section 3 therebetween. That is, information section 14 is disposed at a position corresponding to LED display section 3 (, for example, disposed on the upper side and the lower side of LED display section 3 in the figure). Information section 14 has first information section 15 and second information section 16. An item of welding conditions shown in each of information sections 15 and 16 is indicated by the light-on state of LED display section 3.
First information section 15 shows first welding information B including, for example, first item Bl, second item B2, and third item B3, as shown in Fig. 3.
Similarly, second information section 16 shows second welding information C including, for example, first item Cl, second item C2, and third item C3, as shown in Fig. 3.
Of first welding information B and second welding information C, first item Bl and first item Cl are disposed at positions corresponding to first LED display section Al (i.e., disposed on the upper side and the lower side of section Al); second item B2 and second item C2 are disposed at positions corresponding to second LED display section A2 (i.e., disposed on the upper side and the lower

side of section A2); and third item B3 and third item C3 are disposed at positions corresponding to third LED display section A3 (i.e., disposed on the upper side and the lower side of section A3). The items of first welding information B and second welding information C are, for example, printed on a label to be affixed to information section 14 of operating section.2 or are directly printed on the surface of information section 14 of operating section 2.
Switching section 4 switches light-on segment 17a of LED display section 3(, for example, switches between first LED display section Al, second LED display section A2, and third LED display section A3 shown in Fig. 3). When determining section 5 is operated by the operator while segment 17a of LED display section 3 is keeping the light-on state, determining section 5 determines the item of welding conditions of information section 14 corresponding to light-on segment 17a.
That is, welding machine 1 of the first exemplary embodiment has a function with which a welding operator selects a plurality of items on welding information to determine welding conditions. Welding machine 1 has display section 3, information section 14, switching section 4, and determining section 5. In the structure above, welding information is selected and determined by operation of switching section 4 and determining section 5. Display section 3 has a plurality of LEDs 3a each of which having a plurality of segments 17. Information section 14 is positioned so as to correspond to segment 17a. Information section 14 displays welding information indicated by light-on segment 17a. Switching section 4 switches the welding information of information section 14 by switching light-on segment 17a. In response to operation by the operator while segment 17a is keeping the light-on state, determining section 5 determines the welding information corresponding to light-on segment 17a.

With the structure above, the operator can set welding information by-only operating switching section 4 and determining section 5 while viewing LED display section 3. That is, optimum welding conditions can be easily obtained. The structure allows an operator to set welding conditions easily even if the operator does not have much knowledge about the welding conditions.
Besides, the structure with no need for a liquid crystal display and many switches for setting welding conditions contributes to simply-structured operating section 2, decreasing the cost and time for producing welding machine 1.
.The workings of welding machine 1 having operating section 2 structured above will be described. The description below is given on the operation in which welding conditions are set by determining welding parameters.
The welding operator operates mode setting section 6 and selects the welding-condition setting mode to call up the welding conditions stored in welding machine 1. When the welding-condition setting mode is selected, in first LED display section Al that corresponds to first welding information B, segment 17a corresponding to first item Bl of first.welding information B lights up. That is, light-on segment 17a above indicates that first item Bl'of first welding information B is' selected.
To change the selected item of first welding information B, the operator operates switching section 4. Each time the operator operates switching section 4, segment 17a corresponding to each item of first welding information B lights on in turn.
For example, when the operator operates switching section 4 one time under the condition in which segment 17a corresponding to first item Bl of first welding information B of first, information section 15 is in the light-on state,

light-on segment 17a moves from the position corresponding to first item Bl to the position corresponding to second item B2 of first welding information B. When the operator operates switching section 4 once more, light-on segment 17a moves to the next position. The operator operates switching section 4 until light-on segment 17a reaches the position corresponding to the desired item, and then operates determining section 5. Through the operation, a desired item is finally selected.
After the selection of welding information B is made, selection of second welding information C of second information section 16 follows. That is, segment 17a of first LED display section Al corresponding to first item Cl of second welding information C lights up. As with the selection above, operating switching section 4 and determining section 5 enables the operator to select a desired item of second welding information C of second information section 16.
That is, information section 14 of welding machine 1 of the first exemplary embodiment has first information section 15 and second information section 16. First information section 15 is disposed on the upper side of display section 3 and displays first welding information B. Second information section 16 is disposed on the lower side of display section 3 and displays second welding information C. First welding information B and second welding information C may be determined by the following operation of switching section 4 and determining section 5. Until the operator operates determining section 5, the light-on state of segment 17a corresponding to first welding information B can be changed in turn by operating switching section 4. After the operation of determining section 5 for determining first welding information B, until the operator operates determining section. 5, the light-on state of segment 17a corresponding to second welding information C can be changed in turn by operating switching section 4. That is, operating determining section 5

enables the operator to determine second welding information C. In the structure above, the light-on state of segment 17a corresponding to first welding information B and second welding information C may be changed in turn or may be repeatedly changed by operating switching section 4 until determining section 5 is operated.
The structure allows an operator to set welding conditions easily even if the operator does not have much knowledge about the welding conditions. Besides, the structure with no need for a liquid crystal display and many switches for setting welding conditions contributes to simply-structured operating section 2, decreasing the cost and time for producing welding machine
1.
In response to determination of the welding information items, welding machine 1 calls up welding parameters, such as a welding current value, suitable for the welding information items determined by the operator according to data stored in the storage section, and LED display section 3 displays the welding current value.
Next, a setting example of welding conditions in welding machine 1 of the first exemplary embodiment will be described with reference to Fig. 4 through
Fig. 10.
Fig. 4 shows a specific example of operating section 2 described with
reference to Fig. 3. Operating section 2 of Fig. 4 has LED display section 3,
switching section 4, determining section 5, and mode setting section 6.
Switching section 4 is, for example, a jog dial. Determining section 5 and mode
setting section 6 are, for example, push-button switches. In the structure
above, switching section 4 offers easy and effective switching operation of
desired items of welding information, and determining section 5 offers quick
and reliable determining operation of selected items of welding information.

LED display section 3 is formed of first LED display section Al, second LED display section A2, and third LED display section A3. For example, each of display sections Al through A3 is a 7-segment LED having seven segments 17, as shown in Fig. 4. The structure allows display section 3 to serve not only as a light-on/light-off indicator but also as a numeric-character display, providing welding information in a specific and appropriate way.
LED display section 3 further contains LED 12 and LED 13. LED 12 lights on when LED display section 3 displays a current value, and LED 13 lights on when the operator selects a rod diameter of welding rod.
Welding machine 1 contains an item of "materials" as first welding information B shown in first information section 15 and an item of "positions" (welding positions) as second welding information C shown in second information section 16. Further, welding machine 1 contains an item of "welding-rod diameters" as third welding information D, which differs in selecting operation from the item of "materials" of first welding information B and the item of "positions" of second welding information C. That is, welding machine 1 has three kinds of welding information items.
The item of "materials" of first welding information B contains an item of "mild steel" as first item Bl and an item of "stainless steel" as second item B2. The item of "positions"—which show a direction to which the tip of the welding rod points—of second welding information C contains an item of "flat position" as first item Cl and an item of "overhead/vertical positions" as second item C2.
Of first welding information B and second welding information C of welding machine 1, one may be information on the material of a workpiece, and the other may be information on the welding positions. The structure above allows an operator to set welding conditions easily even if the operator does not have much'knowledge about the welding conditions.

As for the item of "welding-rod diameters" of third welding information D, which will be described later in detail, the operator can determine the diameter of the welding rod within the range of 2. 0 mm to 8. 0 mm in increments of 0. 1 mm.
On the upper side of first LED display section Al formed of a 7-segment LED, an item of "mild steel" as first item Bl is shown as the item of "materials" of first welding information B. Similarly, on the upper side of second LED display section A2, an item of "stainless steel" as second item B2 is shown as the item of "materials" of first welding information B.
Besides, on the lower side of first LED display section Al, an item of "flat position" as first item Cl is shown as the item of "positions" of second welding information C. Similarly, on the lower side of second LED display section A2, an item of "overhead/vertical positions" as second item C2 is shown as the item of "positions" of second welding information C.
First, the welding operator selects the welding-condition setting mode by operating mode setting section 6. In response to selection of the welding-condition setting mode, segment 17a positioned in the upper part of first LED display section Al—corresponding to first item Bl of "mild steel" —lights up, as shown in Fig. 5. The state of Fig. 5 indicates that the item of "mild steel" is currently selected as first welding information B.
To change the item of "materials" of first welding information B from first item Bl of "mild steel" to second item B2 of "stainless steel", the operator operates switching section 4, for example, turns the jog dialas switching section 4. In response to the operation, segment 17a positioned in the upper part of second LED display section A2—corresponding to second item B2 of the item .of "materials" of first welding information B—lights up, as shown in Fig. 6. The state of Fig. 6 indicates that the item of "stainless steel" is currently selected as

first welding information B.
Each time the operator operates switching section 4, the display changes between the state of Fig. 3 and the state of Fig, 4 in turn and repeatedly, until the operator operates determining section 5. The operator operates determining section 5 finally to determine the item of "materials" of first welding information B.
After the operator determines the item of "materials" of first welding information B by operating determining section 5, welding machine 1 prompts the operator to select the item of "positions" of second welding information C. Fig. 7 shows the state above. Segment 17a positioned in the lower part of first LED display section Al—corresponding to first item Cl of "flat position" of the item of "positions" of second welding information C—lights up, as shown in Fig. 7. The state of Fig. 7 indicates that the item of "flat position" is currently selected as second welding information C.
Like in the determining operation of first welding information B, the operator operates switching section 4 and determining section 5 to determine the item of second welding information C. Each time the operator operates switching section 4, the display changes between the state of Fig. 7 and the state of Fig. 8 in turn and repeatedly, and then the operator operates determining section 5 finally to determine the item of second welding information C.
After the operator determines the item of second welding information C, welding machine 1 prompts the operator to select the value of "welding-rod diameters" of third welding information D. Fig. 9 shows the state above. . That is, first LED display section Al, second LED display section A2, third LED display section A3, and LED 13 light up. The numeric characters shown in second LED display section A2 and third LED display section A3 indicate that a

welding-rod diameter of 2. 0 mm is currently selected.
The value of the welding-rod diameter shown in LED display section 3 can be changed, within the range of 2. 0 mm to 8. 0 mm, by operating switching section 4. When the operator operates determining section 5 with a desired value of the welding-rod diameter shown in LED display section 3, the value is determined as the welding-rod diameter.
Through the operation above, the item of "materials" of first welding information B, the item of "positions" of second welding information C, and the item of "welding-rod diameters" of third welding information D are determined. According to the determined items, welding machine 1 calls up welding parameters such as welding current suitable for the items. For example, in Fig. 10, LED display section 3 displays a welding current value and LED 12 lights up, i.e., Fig. 10 shows a welding current value of 100 A as a determined welding condition.
In welding machine 1 of the first exemplary embodiment, the process of determining welding information may be structured as follows. After the items of first welding information B and second welding information C are determined, display section 3 displays a welding-rod diameter. The value of the welding-rod diameter can be changed in turn by operating switching section 4. When the operator operates determining section 5 with a desired value of the welding-rod diameter shown in LED display section 3, the value is determined as the welding-rod diameter. The structure allows an operator to set welding conditions in an easy and reliable way even if the operator does not have much knowledge about the welding conditions. In the structure above, through the operation of switching section 4, the value of the welding-rod diameter may be not only changed in turn but also repeatedly changed.
Further, the process of determining welding conditions may be structured

as follows. Upon determination of first welding information B, second welding information C, and a value of the rod diameter, welding machine 1 determines a value of welding current as a welding condition according to the three information items (i.e., first welding information B, second welding information C, and a value of the rod diameter), and displays the welding current value on display section 3. The structure allows an operator to set welding conditions in an easy, reliable, and effective way even if the operator does not have much knowledge about the welding conditions.
The workings of welding machine 1 will be described with reference to Fig. 2. First storage 7 stores a relationship between light-on segment 17a of LED display section 3 and the welding information items. Second storage 8 stores the range of welding-rod diameter (, for example, the range from 2. 0 mm to 8. 0 mm). Third storage 9 stores a table or a formula that defines correspondences between the following values: the values of the items of first welding information B, the values of the items of second welding information C, the values of the items of third welding information D, and the welding current value as a welding condition. Fourth storage 10 stores determined welding parameters, for example, a welding current value.
Controller 11 changes the display of LED display section 3 according to operation of switching section 4, determining section 5, and mode setting section 6 and the information stored in first storage 7 and second storage 8. According to the operation of determining section 5 and information stored in first storage 7 and second storage 8, controller 11 accepts the selected items from first welding information B and second welding information C, and a value of third welding information D. Controller 11 determines a welding current value as a welding condition according to the selected information items above and information stored in third storage 9; at the same time, the current value is

shown in LED display section 3 and is stored in fourth storage 10. With use of such a determined welding current value, welding machine 1 performs welding work.
According to welding machine 1 of the first exemplary embodiment, as described above, the operator operates switching section 4 and determining section 5 while viewing LED display section 3. Through the operation above, the operator can easily set the welding conditions: a material of the workpiece; a welding position; and a diameter of the welding rod. Determining the welding conditions automatically provides welding parameters such as a welding current value suitable for the welding conditions above.
The setting operation with visual confirmation as described above allows an operator—even if the operator does not have much knowledge about the welding conditions and welding parameters—to have easy and smooth data entry. Besides, welding machine 1 automatically determines welding parameters such as a welding current value so as to be suitable for the welding conditions entered by the operator. Therefore, no need for the operator to carry out the setting operation of welding parameters that usually requires a wealth of knowledge and experience. In particular, setting a welding current value in the welding parameters rests largely on wide experience and intuition of a welding operator, and it is therefore difficult for an inexperienced operator. However, according to welding machine 1 of the first exemplary embodiment, the operator inputs welding information (i.e. welding conditions) with the use of switching section 4 and determining section 5 while viewing LED display section 3, and in response to the welding conditions selected by the operator, welding machine 1 determines welding parameters. It is useful particularly for an inexperienced welding operator. The item of "materials" of workpieces, the item of "welding positions", and the item of "welding-rod diameters" are

easily understood information even for an inexperienced welding operator. That is, setting such an easy-to-understand item only enables the operator to obtain welding parameters such as a welding current value that may be normally determined by an experienced welding operator. The structure is therefore useful especially for an inexperienced.operator.
Besides, the structure has no need for having, for example, a liquid crystal display for showing text information. The operator can perform the setting operation with the use of display section 3 with a plurality of LEDs 3a each of which having a plurality of segments 17 for showing alphanumerical characters, allowing the welding machine to be produced at low cost. The welding conditions needed for stick welding is a few in number, and therefore, the structure of the first exemplary embodiment is particularly suitable for a welding machine for stick welding.
Although the description of the first exemplary embodiment introduces an example in which three LEDs 3a are disposed, it is not limited to; increasing LED 3a in number allows the structure to have more kinds of welding information items or more selection items for each welding information item.
For example, Fig. 11 shows the structure having four LEDs 3a where the items of welding information correspond to each LED 3a. Compared to the structure shown in Fig. 4, the structure of Fig. 11 increases selectable items in number for one item of welding information. Fig. 11 shows an example in which an item of "connections" and an item of "joints" are disposed on the second information section.
Fig. 12 shows an example in which four LEDs 3a are disposed and divided into two sets for showing different items so as to correspond to four items of welding information. Specifically, in the structure of Fig. 12, first information section 15 shows an item of "materials" and an item of "pulses/no

pulses" as welding information; whereas, second information section 16 shows an item of "welding positions" and an item of "craters/no craters", so that LEDs 3a show four kinds of welding information items to be selected by the operator. That is, compared to the example of Fig. 11, the structure of Pig. 12 can display more items to be selected as welding information. The structure of Fig. 12 has two selection items for each welding information item.
Although the structure of the first exemplary embodiment employs a 7-segment LED, it is not limited to; as shown in Fig. 13, a 16-segment LED formed of 16 segments 17 may be employed. As shown in Fig. 13, the structure having a 16-segment LED enables the operator to have three selection items shown by one LED 3b for each welding information item. In Fig. 13A, light-on segment 17b indicates that an item of "mild steel" is currently selected. In Fig. 13B, light-on segment 17b indicates that an item of "copper" is currently selected. In Fig. 13C, light-on segment 17b indicates that an item of "aluminum" is currently selected.
In this way, using LED 3b with a plurality of segments 17 allows the upper part of one LED 3b to correspond to one welding information item. Similarly, when second information section 16 containing other welding information items is disposed on the lower side of each LED 3b of Fig. 13A, Fig. 13B, and Fig. 13C, the operator can select a desired item by lighting on segment 17b corresponding to the item.
INDUSTRIAL APPLICABILITY
The arc welding machine of the present invention has a low-cost, simple structure with no need for a liquid crystal display and many switches for setting welding conditions. The structure allows an operator to easily set desired welding conditions and welding parameters even if the operator does not have

much knowledge about welding. It is therefore useful for a welding machine that performs welding operation according to determined welding conditions.
REFERENCE MARKS IN THE DRAWINGS
1 welding machine
2 operating section
3 LED display section 3a, 3b, 12, 13 LED '
4 switching section
5 determining section
6 mode setting section
7 first storage
8 second storage
9 third storage
10 fourth storage
11 controller

15 first information section
16 second information section
17 segment
17a, 17b light-on segment

CLAIMS
1. A welding machine having a function of determining welding
conditions by selecting a plurality of welding information items, the welding
machine comprising:
a display section with a plurality of LEDs, each of the LED having a plurality of segments;
an information section disposed at a position corresponding to a segment, the information section for displaying a welding information item indicated by the segment in a light-on state;
a switching section for changing the. welding information item shown in the information section by switching the light-on segment; and
a determining section for determining the welding information item corresponding to the light-on segment by being operated while the light-on segment is keeping the light-on state,
wherein, a desired welding information item is selected and then determined by operating the switching section and the determining section.
2. The welding machine according to claim 1,
wherein the information section has a first information section disposed on an upper side of the display section so as to display a first welding information item and a second information section disposed on a lower side of the display section so as to display a second welding information item,
operating the switching section allows the light-on segment corresponding to the first welding information item to be changed in turn until a time when the determining section is operated, and

after the first welding information item is determined by operating the determining section, operating the switching section allows the light-on segment corresponding to the second welding information item to be changed in turn until the determining section is operated, and operating the determining section allows the second welding information item to be determined.
3. The welding machine according to claim 2,
wherein, of the first welding information item and the second welding information item, one information item relates to material of workpieces, and the other information item relates to welding positions.
4. The welding machine according to claim 3,
wherein after determination of the first welding information item and the second information item, the display section displays a value of a welding-rod diameter, and
operating the switching section allows the value of the rod diameter to be changed in turn, then operating the determining section allows the value shown in the display section to be determined as the rod diameter.
5. The welding machine according to claim 4,
wherein upon determination of the first welding information item, the second welding information item, and the value of the welding-rod diameter, according to three kinds of information items, i.e., the first welding information item, the second welding information item, and the value of the welding-rod, a welding current value as a welding condition is determined and then displayed in the display section.

6. The welding machine according to any of claim! through claim 5, wherein the display section is formed of a 7-segment LED.
7. The welding machine according to any of claim 1 through claim 5, wherein the switching section has a jog dial, and
the determining section has a push-button switch.