JPH0214854Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of the Invention This invention relates to an automatic brazing machine that automatically gas brazes a muffler of a refrigerant pipe, as used in, for example, an air conditioner.

(b) Background of the invention Conventionally, as the automatic brazing machine of the above example, there is a device having the following structure, for example.

That is, a starter pipe is arranged near the burner, and during automatic gas brazing, a gas such as oxygen acetylene gas is ignited by the pilot light of the pilot pipe mentioned above, and the workpiece (base material) is heated by the ignited gas flame. This device performs automatic gas brazing by supplying and melting a brazing material to a predetermined brazing location of the heated workpiece.

However, with the above-mentioned device using a pilot flame, there is a problem that good ignition cannot be obtained because the pilot flame goes out due to wind pressure.Furthermore, because a small amount of gas is constantly discharged to light the pilot flame, the gas consumption is low. had a major problem.

(c) Purpose of the invention The purpose of this invention is to provide an automatic brazing machine that can perform reliable automatic ignition and reduce gas consumption.

(d) Summary of the invention In this invention, the nozzles of metal torches are arranged opposite to the workpiece placed at a predetermined position, and the tip of the discharge ignition rod of the DC ignition circuit is connected to the nozzle through a predetermined discharge gap. It is characterized by being an automatic brazing machine that can be separated.

(e) Effects of the invention According to this invention, the tip of the discharge ignition rod is set to be close to the crater at the time of ignition, and at least a high voltage is generated at the output of the above-mentioned DC ignition circuit at the time of ignition. By setting this, ignition can be performed by the discharge generated between the discharge ignition rod and the metal nozzle.

As a result, reliable ignition can be performed without being affected by wind pressure, etc., and gas consumption can be reduced compared to devices with a conventional pilot ignition structure.

(F) Embodiment of the invention An embodiment of the invention will be described below in detail based on the drawings.

The drawings show an automatic brazing machine, Figures 1 and 2.
3, this automatic brazing machine has the following components: a brazing material supply section 2 on the back of the housing 1; a feed line section 4 that feeds the brazing material 3 from the rear of the housing 1 to the front; and a workpiece 5 that is heated. a gas supply section 6 that supplies a gas such as oxygen acetylene gas, a work holder 7 as a work mounting jig that holds the work 5 in a predetermined position, and an ignition section 8 that ignites the above-mentioned gas (see Fig. 7). It is equipped with

As shown in FIGS. 1 and 3, the above-described brazing material supply section 2 has five supply units 9 in total, two at the top and three at the bottom, on the back surface of the housing 1.

The above-mentioned supply unit 9 is constructed as shown in FIG.

That is, a drum shaft 11 is rotatably protruded rearward via a bearing 10 on the back surface of the housing 1,
A drum 13 having an annular recess 12 around which a wire brazing material 3 is wound is loosely fitted onto the drum shaft 11 .

Further, a drum cover 14 that covers the circumferential outer side and rear side of the drum 13 is loosely fitted onto the drum shaft 11, and a nut 17 is screwed into the threaded portion 15 at the rear end of the drum shaft 11 via a washer 16. By that,
The drum cover 14 described above is rotatably held on a shaft.

And, on the upper part of the drum cover 14 mentioned above,
By drilling a through hole 18 and extending a wire 19 having a circular cross section along the edge of the through hole 18, a substantially rectangular brazing material supply hole 20 is formed.

Furthermore, the annular recess 1 in the drum 13 described above
The brazing material 3 wound around the brazing material 2 is inserted into the brazing material supply hole 2 described above.
It is derived upward from 0.

As shown in FIG. 3, a total of five supply units 9
The brazing filler metals 3 respectively led out from the housing 1 are introduced into the above-mentioned feed line portion 4 via a first guide 21 and a second guide 22 on the back surface of the housing 1.

This feed line section 4 is constructed as shown in FIGS. 1, 5, and 6.

That is, this wire feeding section 4 is provided with a lower opposing roller mechanism 23 and an upper opposing roller mechanism 24 for each unit brazing material 3.

As shown in FIG. 5, the above-mentioned lower opposing roller mechanism 23 has a grooved roller 26 on one roller shaft 25.
, and the guide roller 28 is attached to the roller shaft 27 on the other side.
So-called set collars are provided respectively, and the groove 29 of the grooved roller 26 is set to be relatively wide with respect to the wire diameter of the brazing material 3.
The guide roller 28 on the other side is configured to roll into contact with the brazing filler metal 3 passing through.

Further, the above-mentioned upper opposed roller mechanism 24 is the sixth
As shown in the figure, a grooved roller 31 is provided on the drive shaft 30 on one side, and a pressure roller 33 is provided on the adjusting shaft 32 on the other side.
The concave groove 34 is set to be approximately equal to the wire diameter of the brazing material 3,
The pressure adjustment knob 35 (see Fig. 1) makes it possible to adjust the contact pressure of the pressure roller 33 against the brazing material 3, and the rotation shaft 37 of the DC servo motor 36 is interlocked with the drive shaft 30 described above. The brazing filler metal 3 is configured to be fed in a fixed amount by controlling the drive of a DC servo motor 36.

And the above-mentioned upper and lower opposed roller mechanisms 24, 2
3 and the DC servo motor 36 are covered with a box-shaped box 38.

Above the box 38 is a tube guide 39.
In addition to fixing the tube guide 39,
A flexible tube 41 is stretched between a predetermined brazed portion 5a of the workpiece 5 and a feed line guide 40 made of metal, for example, copper, and the brazing material 3 from the box 38 is passed through the tube guide 39 and the flexible tube 41. The wire is fed to the above-mentioned predetermined brazing portion 5a via the flexible tube 41 and the wire feed guide 40.

Here, the above-mentioned five feed line guides 40 in total are configured to be vertically adjustable and angle adjustable by the structure described below.

That is, support poles 42, 42 are erected and fixed on both sides of the upper surface of the housing 1, and elevating blocks 44, 44 fixed in position with screws 43 are disposed on each of these support poles 42, 42. A shaft 45 is horizontally suspended between 44 and 44.

A total of five guide holders 46 are arranged on this shaft 45 at equal intervals, and the above-mentioned feed line guide 40 is fixed to each of these guide holders 46.

Therefore, by adjusting the vertical positions of the above-mentioned lifting blocks 44, 44, the feed line guide 40 can be adjusted up and down, and the above-mentioned shaft 4 can be adjusted up and down.
By tilting the guide holder 46 to an arbitrary angle using the rotation fulcrum 5, the angle of the feed line guide 40 can be adjusted.

In order to heat the predetermined brazing portion 5a of the workpiece 5 described above, the gas supply section 6 that supplies gas to the brazing portion is constructed as shown in FIGS. 1 and 2.

That is, a torch clamp 48 whose angle can be adjusted around a support shaft 47 is provided, and a base tube 50 of a torch 49 is fixed to the upper part of this torch clamp 48.

A housing 1 is provided at the tip of a conduit 51 extending forward (to the left in FIGS. 1 and 2) from the base tube 50 described above.
A common pipe 52 having a length substantially equal to the full width of the upper surface is fixed and communicated. This common pipe 52 is supported by appropriate means.

From this common pipe 52, three gas conduit pipes 53 are connected to each workpiece 5, and a predetermined brazed portion 5a is connected to the tip of each gas conduit 53.
Each of the metal, for example, copper or brass craters 54 facing each other is attached.

In addition, the hose port 55 provided on the base pipe 50 described above,
56 are connected to an oxygen supply hose (not shown) and an acetylene gas supply hose (not shown), respectively.

Further, a piston rod 58 of a cylinder 57 is connected to the lower part of the torch clamp 48 that supports the base tube 50 described above, and the entire torch 49 is configured to be movable in the front and rear directions along a sliding guide 59.

Next, the configuration of the ignition section 8 that ignites the above-mentioned gas will be explained based on FIG. 7.

A predetermined discharge gap g (second
(see figure), specifically, a discharge ignition rod 60 is provided that approaches and separates with a distance of about 3 mm, and a total of five discharge ignition rods 60 are made of heat-resistant tungsten, and each of these discharge ignition rods 60 is It is connected to an elevating plate 62 via a child 61.

A cylinder 6 is provided on the lower surface of this elevating plate 62.
Three piston rods 64 are connected, and the above-mentioned elevating plate 62 and each discharge ignition rod 60 are moved up and down along guides 65, 65 by the reciprocating movement of the cylinder 63.

The above-mentioned discharge ignition rod 60 is connected to the output side of the DC ignition circuit 66 shown in FIG.
7, the power switch 68 of the DC ignition circuit 66 is turned off when the elevating plate 62 is lowered as shown by the imaginary line in FIG.
is turned OFF, and the power switch 68 of the flow ignition circuit 66 is turned ON when the elevating plate 62 moves upward as shown by the solid line in FIG.

The circuit configuration of the above-mentioned DC ignition circuit 66 is as shown in FIG.

That is, the primary winding 71 of the step-up transformer 70 is connected to the positive terminal of the DC power source 69, for example, 9 volts DC, via the power switch 68, and the DC power source 69
The emitter electrode of a transistor 72 is connected to the negative electrode of the transistor 9.

The base electrode of the transistor 72 described above is connected to one end of the primary winding 71 of the step-up transformer 70 via a resistor 73, and the collector electrode of the transistor 72 is connected to the other end of the primary winding 71 described above.

Further, a capacitor 76 is connected between both ends of the secondary winding 74 of the step-up transformer 70 described above via a high frequency diode 75.

Furthermore, the primary winding 81 of an ignition transformer 80 is connected to both ends of the capacitor 76 through a parallel circuit 79 consisting of a diode 77 and a reverse-blocking diode-thyristor 78. The above-mentioned discharge ignition rod 60 is connected to one end of the secondary winding 82 of the ignition transformer 80.

The above-mentioned DC ignition circuit 66 is connected to a power switch 68.
When turned on, the step-up transformer 70, transistor 72, resistor 73, and high-frequency diode 75
A DC-DC converter consisting of acts and charges the capacitor 76.
When the charging voltage of the reverse-blocking two-terminal thyristor 78 becomes higher than the breakover voltage of the reverse-blocking two-terminal thyristor 78, the reverse-blocking two-terminal thyristor 78 is turned on, and a capacitor discharge current instantly flows through the primary winding 81 of the ignition transformer 80. This circuit generates a high voltage, for example, 12,000 to 13,000 volts, in the secondary winding 82 of the ignition transformer 80.

By the way, in the housing 1 mentioned above, there is a control section 83 that applies command pulses to the DC servo motor 36.
A so-called control unit is built in, and the above-mentioned DC servo motor 36 is driven by command pulses from this control unit 83, and the brazing material 3 is configured to be controlled by a predetermined length required for brazing.

The illustrated embodiment is configured as described above,
The action will be explained below.

Now, when the piston rod 64 of the cylinder 63 shown in FIG.
When the piston rod 64 is turned on, the above-mentioned upward movement of the piston rod 64 causes the discharge ignition rod 60 and the metal nozzle 5 to
4, a discharge gap g (see FIG. 2) of a predetermined length, for example, about 3 mm is formed.

While the above-mentioned power switch 68 is turned on, a high voltage of 12 to 13 KV is continuously generated in the discharge ignition rod 60 in response to charging and discharging of the capacitor 76. Electric discharge occurs between the two, and the oxygen acetylene gas is reliably ignited when gas is supplied to the torch 49 or when gas is blown out from the torch 49.

Ignition caused by this discharge is reliable ignition that is completely unaffected by wind pressure and the like.

After the above-mentioned ignition, the piston rod 64 of the cylinder 63 moves downward to lower the discharge ignition rod 60 via the elevating plate 62, and the sensing plate 67 of the elevating plate 62 turns on the power switch 68.
Turn it off.

On the other hand, due to the above-mentioned ignition, a predetermined portion of the workpiece 5 is heated by the oxyacetylene flame from the crater 54.

As a result of this heating, when the predetermined brazed portion 5a is heated to a predetermined temperature, for example, 450° C. or higher, the control portion 8
When the direct current servo motor 36 is driven by a command pulse from 3 and a predetermined amount of brazing material 3 is supplied from the feed line section 4, the molten brazing material is uniformly spread over the above-mentioned predetermined brazing section 5a, and automatic brazing is performed. can be done.

In short, by bringing the tip of the above-mentioned discharge ignition rod 60 close to the crater 54 via the discharge gap g during ignition, and applying the high voltage output from the DC ignition circuit 66 to the discharge ignition rod 60,
The gas can be ignited by the discharge generated between the discharge ignition rod 60 and the metal nozzle 54 described above.

As a result, it is possible to perform reliable ignition that is completely unaffected by wind pressure, etc., and it is also possible to reduce gas consumption compared to devices with a conventional pilot ignition structure.

In addition, instead of the DC ignition circuit shown in Fig. 8,
It goes without saying that other DC ignition circuits using other DC-DC converters may be used.

Furthermore, although oxygen acetylene gas was used in the above-mentioned embodiments, it goes without saying that butane, propane, and other flammable gases may also be used.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, and Fig. 1 is a side view of the automatic brazing machine, Fig. 2 is a plan view of the automatic brazing machine, Fig. 3 is a back view of the automatic brazing machine, and Fig. 4 is a side view of the automatic brazing machine. is a sectional view of the supply unit, FIG. 5 is an explanatory diagram of the lower opposed roller mechanism, FIG. 6 is an explanatory diagram of the upper opposed roller mechanism, and FIG. 7 is a schematic front view showing the structure of the ignition part. FIG. 8 is an electrical circuit diagram of the DC ignition circuit. 5...Workpiece, 49...Torch, 54...Tinder, 60...Discharge ignition rod, 66...DC ignition circuit, g...Discharge gap.

Claims (1)

[Scope of Claim for Utility Model Registration] A metal torch is placed on a workpiece placed in a predetermined position, and a crater is arranged opposite to it, and the tip of a discharge ignition rod of a DC ignition circuit can be brought into contact with and separated from the said crater via a prescribed discharge gap. Automatic brazing machine installed in