JPH0242393Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Field of Industrial Application] The present invention relates to an electric resistance welding machine, and in particular controls the electrode pressure of a spot welding machine along with other welding conditions, such as welding current and welding time, as well as the material and material of the workpiece. This has been improved so that it can be electrically controlled in response to changes in several conditions such as plate thickness. [Prior art and its problems] As is well known, in resistance welding machines, the three major welding elements such as welding current, welding time, and electrode pressure are adjusted according to welding conditions in order to obtain optimal welding quality. There is a need to. In general, the welding current and welding time for spot welding are
It is usually controlled by a timer device. On the other hand, among the three major elements of welding, only the electrode pressure is currently adjusted inefficiently using a manual pressure reducing valve installed in the welding machine. Coupled with the recent increase in the popularity of spot welding robots and the complexity of setting multiple conditions on microcomputer control devices, it takes more time to set conditions, and most electrode pressure adjustments are done manually. Because it is a work that requires a lot of work, it is often done at a height higher than one's height, and is often avoided as a cumbersome task.Normally, only adjusting the welding current and welding time is done, but the optimal adjustment of the pressurizing force is rarely done. The reality is that it is not. [Purpose of the present invention] The present invention is based on a welding condition series consisting of one set of welding current, welding time, pressurizing force, etc., which are said to be the three major elements of spot welding. To provide a spot welding machine for multi-condition control which can be electrically switched. [Summary of the present invention] The present invention is an electric resistance welding machine that welds a workpiece by applying pressure and applying current through an electrode tip.
A timer device capable of selecting welding control conditions such as welding current and welding time according to the appropriate welding conditions of the workpiece, and sequentially controlling various electrical and/or mechanical operations consisting of these various elements; Turn on multiple switching valves to supply secondary pressure to the pressure cylinder of the welding machine
- A fluid pressure regulator that is controlled in stages by a combination of -OFF and ON - OFF for the switching valve of this fluid pressure regulator.
and a pressure controller that selects and outputs a combined electric signal, and the fluid pressure regulator is provided with one of the pressurizing cylinders.
The primary pipe line that supplies the next pressure and the 2 line that takes out the secondary pressure
A pressure regulated device such as a pilot regulator is installed in the middle of the main pipeline consisting of the primary pipeline, and the pilot pipeline branched from the primary pipeline is connected to the pilot section of the pressure regulated device. A regulator for variable pressure adjustment range and a fixed throttle valve are installed in the middle of the pilot pipe, and two pilot pipes are installed in the pilot pipe that passes through the throttle valve.
A plurality of sets of control units each consisting of a direction switching valve and a variable throttle valve are connected in parallel, and the timer device and pressure control unit are supplied with welding currents in advance according to the appropriate welding conditions of several types of objects to be welded. Enter the welding condition series with one set of welding time, electrode pressure, etc. for each series, and select the welding condition series corresponding to these multiple sets of conditions for each series using a series selection switch or contact signal, etc. It is characterized by being configured so that it can be switched all at once. [Embodiments of the present invention] Hereinafter, "embodiments" of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a spot welding machine according to the present invention. An upper arm 1a and a lower arm 1b are fixed to the front of the main body of the spot welding machine 1, and a movable ram 4 in a guide case fixed to the tip of the upper arm 1a moves up and down by the fluid pressure of the pressurizing cylinder 3. An electrode chip 6 is held at the tip of the movable ram via an upper conductor 5. On the other hand, an electrode chip 7 facing the electrode chip 6 is held on the lower arm 1b via a lower conductor 8. A welding transformer 9 housed within the main body is connected to a flexible plate 10 and a conductive member 11. On the other hand, the timer device 12 is used to sequence control the electrical and mechanical operations of the spot welding machine, and generally controls the welding current value (), welding time (T), squeeze time, energization time, etc.
The welding sequence operation is performed by controlling welding control elements such as holding time and opening time. In this case, the setting device for each control element is the timer operation panel 13.
are provided on the top surface of each. On the other hand, the fluid pressure regulator 14 for controlling the pressurizing force
is generally mechanical, and the pressure is adjusted appropriately by turning a handle and checking the pressure with a pressure gauge. However, the fluid pressure regulator 14 installed in the spot welding machine of the present invention is As shown in Figure 1, a pilot regulator is installed in the middle of a main pipeline consisting of a primary pipeline 31 that supplies a primary pressure P ₁ and a secondary pipeline 32 that takes out a desired secondary pressure P ₂ . A pressure regulator 33 such as a regulator or a booster is provided, and a pilot pipe 34 branched from the primary pipe 31 is connected to the pilot section of the pressure regulator 33. On the way, there is a regulator 35 for variable pressure adjustment range and a fixed throttle valve 3.
6 are provided in series. Further, the fixed throttle valve 3
6, a plurality of sets of control units each having a two-way switching valve 37 and a variable shutoff valve 38 connected in series are connected in parallel to the pilot pipe. The variable throttle valves 38a to 38n are set to have different diameters, and their output sides are open to the atmosphere. The secondary side of the pressure regulator 14 is the pressurizing cylinder 3
is connected to the supply pressure port of the pressurizing solenoid valve 39, and its output port is directly connected to the pressurizing cylinder. The next pressure controller 15 connects ON-- to each switching valve 37a to 37n incorporated in the fluid pressure regulator.
It controls the combination of each switching valve by transmitting an OFF combination electric signal. As shown in more detail in FIG. 2, this pressure controller 15, for example, takes a combination of three two-way switching valves 37a to 37c, and outputs two ON-OFF combination electric signals to the two-way switching valves. ³ =8 combination signals can be selected. As the set value of the digital switch changes from 1 to 2...8, the ON-OFF electric signals to the corresponding two-way switching valves are programmed in advance in the selection circuit ROM, and the combined signal is applied to the transistor circuit Tr. The transistor circuit Tr is turned on by each gate signal.
OFF and the two-way switching valve 37 connected to it
A to c are turned on and off to determine the combination. Here, when the digital switch is set to "1", all two-way switching valves are opened, and the secondary pressure is at the lower limit.
When P ₂ min is reached and the digital switch is set to "8", all two-way switching valves are opened and the secondary pressure reaches the upper limit value P ₂ max, and this period is used as an ON-OFF combination signal to the two-way switching valves. The pressure is thus step-controlled. Considering four types of multi-condition settings depending on the material of the workpiece, plate thickness, etc., four digital switches for the pressure controller 15 are prepared in the same way as other digital switches for welding current, welding time, etc. When series selection switches 1, 2, 3, and 4 are selected and turned on, the pressure setting value of the corresponding digital switch is selected and the pressing force is set.
For example, as shown in the table below, the welding condition series of welding current (), welding time (T), and pressure force (P) are set as one set, and the setting values are preset for each of the four series. It turns out.

【table】

Claims (1)

[Scope of utility model registration request] In an electric resistance welding machine that applies pressure and current to the workpiece through an electrode tip, welding control conditions such as welding current and welding time are selected in accordance with the appropriate welding conditions of the workpiece. A timer device capable of sequentially controlling electrical and/or mechanical operations consisting of various elements, and secondary pressure to the pressurizing cylinder of the welding machine is controlled in stages by ON-OFF combinations of a plurality of switching valves. The fluid pressure regulator is equipped with a fluid pressure regulator and a pressure controller that selects and outputs an ON-OFF combination electric signal to the switching valve of the fluid pressure regulator, and the fluid pressure regulator supplies the primary pressure of the pressurized cylinder. A pressure regulated device such as a pilot regulator is installed in the middle of the main pipeline, which consists of a primary pipeline that takes out the secondary pressure, and a secondary pipeline that takes out the secondary pressure, and the pilot pipeline that branches from the primary pipeline , connected to the pilot section of the pressure regulated device, a regulator and a fixed throttle valve for variable pressure regulation range are provided in the middle of the pilot line, and a two-way switching valve and a variable throttle valve are installed in the pilot line passing through the throttle valve. A plurality of sets of control units each connected to a throttle valve are connected in parallel, and the timer device and pressure controller are set in advance to the welding current, welding time, and electrode application according to the appropriate welding conditions for several types of objects to be welded. Input the welding condition series with pressure etc. as one set for each series,
Welding condition series corresponding to these multiple sets of conditions are
A spot welding machine characterized by being configured so that each series can be switched all at once by a series selection switch or a contact signal.