JPH11136909A - Welder driven by internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize reduction in size and weight of a welder driven by an internal combustion engine. SOLUTION: Magnet field for ignition is structured by fitting a flywheel 201 to one end 1c1 of a crank shaft 1c of an internal combustion engine 1 and then fitting a permanent magnet 204 to the external circumference of the flywheel 201. A magnet 2 is formed by providing a generator 2B for igniting, opposite to the magnet field for ignition. Multiple-pole magnet field 31 for generator welding is formed by fitting a rare-earth magnet 36 to the internal circumference side of the flywheel 201. Thereby, a generator for welding 30 is structured by the magnet field, and an armature 34 for generator for welding arranged at the internal side of the flywheel 201.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding machine driven by an internal combustion engine to generate a voltage used for welding.

[0002]

2. Description of the Related Art An internal combustion engine drive welding machine includes: an internal combustion engine; a welding generator driven by the internal combustion engine to generate a three-phase or multi-phase AC output; and a rectifier for rectifying the output of the welding generator. And a DC output obtained from the rectifier is supplied between the welding torch and the base material to perform welding.

[0003] Further, in an internal combustion engine drive welding machine, an ignition device is required to operate the internal combustion engine. Therefore, it is necessary to obtain a voltage for driving the ignition device. Magnets (magnet generators) are widely used as generators for generating voltages for driving ignition devices for internal combustion engines. Magneto includes a flywheel attached to a crankshaft of an engine, a permanent magnet attached to an outer peripheral portion of the flywheel, an ignition core having an ignition core and an ignition power coil wound around the core. And a voltage induced in the ignition power supply coil by a change in magnetic flux generated in the ignition-use electromotive core with the rotation of the flywheel.

As described above, in an internal combustion engine drive welding machine, a welding generator for generating a voltage used for welding and a generator for generating a voltage for driving an ignition device for the internal combustion engine are driven by the internal combustion engine. Conventionally, both ends of a crankshaft of an internal combustion engine are drawn out to the outside, and a magnet and a welding generator are attached to one end and the other end of the crankshaft of the engine, respectively.

FIG. 6 shows an example of a conventional welding machine driven by an internal combustion engine. In FIG. 6, reference numeral 1 denotes an internal combustion engine, 2 and 3 denote magnets and welding generators driven by the internal combustion engine 1, respectively, and 4 denotes a battery. A magnet generator that generates a voltage for charging or a voltage for exciting the field coil of the welding generator 3;
5 is a cover for covering the magneto 2 and a part of the internal combustion engine 1, 6
Is an internal combustion engine ignition device, and 7 is an internal combustion engine start device.

The internal combustion engine 1 has a crankcase 1a, a cylinder 1b, a crankshaft 1c arranged across the crankcase 1a and supported by the crankcase via a bearing, and fitted in the cylinder 1b. Piston 1e connected to crankshaft 1c via connecting rod 1d
And a spark plug 1f attached to the cylinder head. One end 1c1 and the other end 1c2 of the crankshaft 1c are led out.

The magneto 2 has a substantially cup-shaped cast iron flywheel 201 connected to one end 1c1 of the crankshaft of the internal combustion engine, and a permanent magnet for ignition 204 fixed to the outer peripheral portion of a peripheral wall portion 201a of the flywheel. It comprises a flywheel magnet rotor 2A and an ignition generator 2B formed by winding an ignition power supply coil 206 around an ignition generator core 205. The ignition electromotive force 2B is bolted to a mounting portion 1g provided in a cylinder of the internal combustion engine 1 so that a magnetic pole portion provided in an iron core 205 is used as a permanent magnet 204 for ignition.
As a result, the magnet field is opposed to the ignition magnet field formed on the outer peripheral portion of the flywheel via a predetermined gap.

In this example, the primary coil of the ignition coil 206 also serves as an ignition power supply coil, and is connected to the ignition unit 208. The ignition coil 206 and the ignition unit 208 constitute the ignition device 6 for an internal combustion engine. Have been. The ignition unit 208 controls the current flowing in the primary coil of the ignition coil 206 to generate a high voltage for ignition in the secondary coil of the ignition coil at the ignition timing of the engine. The high ignition voltage obtained from the ignition coil 206 is applied to the ignition plug 1f through a high-voltage cord (not shown).

In the example shown, the flywheel 201
The permanent magnet 211 is fixed to the inner periphery of the peripheral wall portion 201a,
The permanent magnet 211 forms a magnet field having a predetermined number of poles. An armature 214 having an armature core 212 and a power generation coil 213 wound around the iron core is disposed inside the flywheel 201. The armature 214 is an armature protruding from a crankcase 1a of the internal combustion engine. It is fastened to the mounting portion 1h by a bolt (not shown). Permanent magnet 21
The magnet field generator configured to generate an output for charging the battery and an excitation output for exciting the welding generator 3 is configured by the magnet field configured by the magnetic field generator 1 and the armature 214.

The cover 5 includes a magnet 2 and a surface of the crankcase 1a of the internal combustion engine on the magnet side, and a cylinder 1 of the engine.
b is formed so as to cover a part of the cylinder 1b of the internal combustion engine, has an exhaust port 5a, and a part facing the bottom wall 201c of the flywheel 201 has an air inlet 5b. have.

On the outer surface of the bottom wall 201c of the flywheel 201, a cup-shaped driven member 7a constituting a part of the internal combustion engine starting device 7 is fixed.
The drive mechanism 7c of the starting device is mounted inside a cup-shaped case 7b mounted so as to close the opening.

The welding generator 3 is a rotating field type synchronous generator, and includes a hollow rotating shaft 302 fixed to the other end 1c2 of the crankshaft 1c of the engine by a bolt 301;
And a stator 304 fixed to the case of the engine.

The rotor 303 is formed by winding a field coil 306 around a rotor core 305, and the field coil 306 includes a slip ring 307 attached to the rotating shaft 302,
It is connected to an output terminal of a rectifier that rectifies the excitation output generated by the magnet generator 4 through a power supply mechanism including a brush 308 that comes into sliding contact with the slip ring.

In the illustrated example, the crankcase 1a of the engine is used.
The generator mounting portion 310 is integrally provided with the generator mounting portion 310 and the cup-shaped end cover 3.
11 and an annular stator core 312 are arranged. An armature coil 313 is wound around the stator core 312, and the stator 304 is constituted by the stator core 312 and the armature coil 313. The stator 304 is fixed to the internal combustion engine by a through bolt (not shown) that penetrates through the stator core 312 and fastens the end cover 311 and the generator mounting portion 310. The output obtained from the armature coil 313 is supplied to the welding load through a rectifier not shown in FIG.

A blower 314 is attached to the end of the rotary shaft 302 of the welding generator 3 on the side of the internal combustion engine, and the rotation of the blower causes a ventilation hole 311 formed in the end cover 311.
The outside air is introduced into the generator 3 from a. The air introduced into the welding generator 3 has a field coil 306 and an armature coil 31 as indicated by an arrow A in the figure.
After cooling down the generator 3 and flowing in the axial direction in the generator, its direction is changed by a blower 314, and the air is discharged to the outside through an exhaust hole 310 a formed in a peripheral wall portion of the generator mounting part 310.

The bottom wall 203 of the flywheel 204
Is provided on the outer surface of the air blower 201e, which generates a centrifugal airflow with the rotation of the flywheel, and is provided on the case 7b of the starter as shown by the arrow B in the drawing by the rotation of the blower 201e. The outside air is introduced into the cover 5 from the air inlet 7 e through the air inlet 5 b of the cover 5.

Part of the air introduced into the cover 5 and sent in the centrifugal direction by the blower blades 201e flows as shown by the arrow C in FIG. 2 to cool the ignition generator 2B and the engine cylinder 1b. While being exhausted from the exhaust port 5a of the cover 5, it is exhausted. The other part of the air sent in the centrifugal direction by the blower blade 201e passes through the gap formed between the flywheel and the engine as shown by the arrow D in FIG. 1 flows while cooling, and is discharged to the outside through the exhaust port 5 a of the cover 5.

To prevent the exhaust gas discharged from the exhaust port 5a of the cover 5 from interfering with the exhaust gas discharged from the exhaust hole 310a of the generator 3, the exhaust hole 310a of the welding generator 3 is prevented.
A partition plate 8 is provided for partitioning between the engine and the exhaust port 5a of the cover 5, and the partition plate 8 is screwed to a cylinder 1b of the engine.

FIG. 7 is a block diagram showing the overall structure of a conventional welding machine driven by an internal combustion engine.
Is an internal combustion engine, 2 and 4 are magneto and magnet generators driven by the internal combustion engine, respectively, and 3 is a welding generator also driven by the internal combustion engine. An ignition unit 208 is connected to the ignition emission of the magneto 2, and a high voltage for ignition induced in a secondary coil of the ignition coil by the ignition unit 208 is applied to an ignition plug of the internal combustion engine 1. The output of the magnet generator 4 is input to a regulator 11 having a rectifying function and a voltage adjusting function, and a charging current is supplied from the regulator 11 to a battery 12. The output of the magnet generator 4 is also provided to the field coil 306 of the welding generator 3 through the rectifier 13.

The welding generator 3 is configured to output a three-phase AC voltage, and the AC output obtained from the welding generator 3 is controlled so that the output current can be phase-controlled by a thyristor. The full-wave rectified by the rectifier 14 is applied to a welding load composed of the arc welding torch 15 and the base material 16.

The output of the battery 12 is input to a control unit 17 for controlling the control rectifier 14. When an electric starter is used as the starter 7 for the internal combustion engine, a battery 12 is connected to a starter motor 18 of the starter.
Is provided.

[0022]

In the internal combustion engine drive welding machine shown in FIG. 6, one end 1 of a crankshaft of the internal combustion engine is provided.
Since the magnet 2 and the magnet generator 4 were mounted on the c1 side, and the welding generator 3 composed of a rotating field synchronous generator was mounted on the other end 1c2 of the crankshaft, the entire welding machine became large and weighed. In addition to being heavy, costs were inevitable.

Further, in the internal combustion engine drive welding machine shown in FIG. 6, it is necessary to provide two blower blades for cooling the inside of the welding generator 3 and the inside of the cover 5, respectively. The inefficiency of the plane was inevitable.

Further, in the internal combustion engine drive welding machine shown in FIG. 6, a cooling air flow path must be formed in two systems, that is, inside the cover 5 of the engine and inside the welding generator 3, so that the cooling structure is not provided. There was a problem that it became complicated.

An object of the present invention is to provide an internal combustion engine drive welding machine capable of reducing the size and weight and reducing the cost.

It is another object of the present invention to provide an internal combustion engine drive welding machine capable of simplifying a cooling structure, reducing windage loss and improving efficiency.

[0027]

SUMMARY OF THE INVENTION An internal combustion engine drive welding machine according to the present invention has an internal combustion engine, a peripheral wall portion and a bottom wall portion on which a boss portion for mounting a rotating shaft is formed. A flywheel coupled to the crankshaft of the engine, a magnet field formed on the inner periphery of the peripheral wall of the flywheel, and an armature core having a magnetic pole portion facing the magnet field inside the flywheel, A welding power generating coil and an ignition device driving power generating coil that are wound around an armature core and generate a voltage used for welding and a voltage for driving an ignition device for an internal combustion engine, respectively, are provided to form a magnet field. Permanent magnets are made of rare earth magnets.

The flywheel may be made of a molded product formed by drawing an iron or iron alloy plate, or may be made of cast iron.

As described above, the magnet field is formed by attaching the rare earth magnet to the inner periphery of the peripheral wall of the flywheel, and the armature core, the welding power generation coil wound around the core, and the ignition device drive When the generator is configured by arranging the generator coil inside the flywheel, by simply arranging the generator only on one side of the crankshaft of the engine, the voltage for driving the ignition device and the voltage used for welding are reduced. Can be generated. Therefore, the axial length can be greatly reduced as compared with a conventional welding machine in which a magnet and a welding generator are attached to both ends of a crankshaft of an internal combustion engine, respectively.

Further, since the rare earth magnet has a remarkably high holding force, the rare earth magnet required for forming the magnet field required for the generator for welding may be small.
Therefore, when the magnet field is formed by using the rare-earth magnet, a generator that obtains a welding voltage can be formed by using a flywheel having the same size as a conventionally used flywheel. The surplus power of the machine can be used to charge the battery.

In order to take advantage of the high performance of rare earth magnets,
It is desirable to improve the magnetic characteristics of the magnetic path of the magnet field, increase the amount of magnetic flux flowing through the magnetic path, and reduce iron loss generated in the magnetic path. Therefore, when the magnetic properties of the magnetic material forming the flywheel are inferior, or when the cross-sectional area of the peripheral wall of the flywheel is small, the peripheral wall of the flywheel is used as a magnetic path (yoke) of the magnet field. Instead, an annular yoke made of a magnetic material having a good magnetic property (a magnetic material having a high saturation magnetic flux density and a high magnetic permeability and a small coercive force) is fitted and fixed to the inner periphery of the peripheral wall of the flywheel. It is preferable that the rare earth magnet is fixed to the inner periphery of the yoke.

In most cases, the welding machine driven by an internal combustion engine generates a voltage for driving an internal combustion engine, an ignition device for igniting the internal combustion engine, and a voltage driven by the internal combustion engine to be used for welding. And a welding generator.

The magneto includes a cast iron flywheel having a peripheral wall portion and a bottom wall portion on which a boss portion for attaching a rotating shaft is formed, the boss portion being connected to a crankshaft of an internal combustion engine.
The flywheel includes an ignition permanent magnet fixed to the outer peripheral portion of the peripheral wall portion, and an ignition electromotive force fixed to the internal combustion engine. The ignition electromotive force is wound around the ignition electromotive core having a magnetic pole portion opposed to the ignition magnet field formed on the outer periphery of the flywheel by the ignition permanent magnet, and the ignition electromotive core. And an ignition power supply coil for generating an AC voltage in synchronization with the rotation of the internal combustion engine.

When the present invention is applied to the welding machine driven by an internal combustion engine as described above, the magnet field for the welding generator formed on the inner periphery of the peripheral wall portion of the flywheel is welded inside the flywheel. An armature core for a welding generator fixed to the internal combustion engine having a magnetic pole portion facing the magnet field for the generator, and a welding power generating coil wound around the armature core for the welding generator. Construct a welding generator. A plate-shaped rare earth magnet is used as a permanent magnet constituting a magnet field for a welding generator.

As described above, the magnet field for the welding generator is formed by attaching the rare earth magnet to the inner periphery of the peripheral wall of the flywheel, and the armature core for the welding generator and the welding wound around the iron core are formed. When the welding generator is configured by disposing the generator coil for the inside of the flywheel, the generator only needs to be disposed on one side of the crankshaft of the engine, and since the welding generator is disposed inside the magneto, The axial length of the welding machine can be greatly reduced as compared with a conventional welding machine in which a magnet and a welding generator are attached to both ends of a crankshaft of an internal combustion engine, respectively.

As described above, according to the present invention, since the axial dimension of the welding machine can be greatly reduced and the flywheel does not need to be particularly large, the welding machine driven by an internal combustion engine can be used. Can be reduced in size and weight.

In the conventional internal combustion engine drive welding machine, the price of the field rotating synchronous generator used as the welding generator accounts for a large proportion of the total price. However, the present invention does not use an expensive rotating field synchronous generator, so that the cost can be significantly reduced.

When the generator is arranged only at one end of the crankshaft of the internal combustion engine as in the present invention, the blower for cooling the internal combustion engine and the generator is provided only at one end of the crankshaft of the engine. Since the cooling structure may be provided, the cooling structure can be simplified.

Further, with the above configuration, since no generator is attached to the other end of the crankshaft of the internal combustion engine, another load can be connected to the other end of the crankshaft as needed. .

In order to take advantage of the high performance of rare earth magnets,
It is desirable to improve the magnetic characteristics of the magnetic path of the magnet field for the welding generator and reduce iron loss generated in the magnetic path. Therefore, instead of using the peripheral wall of a flywheel made of cast iron as a yoke, a magnetic material with better magnetic properties (higher saturation magnetic flux density and permeability and lower coercive force than cast iron forming the flywheel) It is preferable that a ring-shaped yoke made of material) is fitted and fixed to the inner periphery of the peripheral wall portion of the flywheel, and the rare-earth magnet is fixed to the inner periphery of the ring-shaped yoke.

That is, the magnet field for the welding generator is made of a magnetic material having a higher saturation magnetic flux density and a higher magnetic permeability than the cast iron constituting the flywheel and a small holding force, and is fitted on the inner periphery of the peripheral wall of the flywheel. An annular yoke fixed together,
It is preferable that the yoke is composed of n plate-shaped rare earth magnets arranged at equal angular intervals on the inner periphery of the yoke and fixed to the yoke.

In this case, it is preferable to use n rare earth magnets having the same shape and size.

The annular yoke is preferably formed of a laminate of magnetic material plates having higher magnetic permeability and lower coercive force than the cast iron constituting the flywheel.

As the magnetic material having a higher magnetic permeability and a lower coercive force than cast iron, a magnetic material used as a high magnetic permeability magnetic material for a rotating electric machine, for example, a carbon steel sheet, pure iron, or Si of about 1% is used. A magnetic steel sheet, a silicon steel sheet, or a permalloy having a thin sheet of iron containing and coated with an insulating coating on the surface can be used.

As the armature core for the welding generator, an m-pole (m is 2 or more) fixed to the internal combustion engine having a magnetic pole portion facing the magnet field for the welding generator inside the flywheel. It is preferable to use an even-numbered annular star core.

When an annular yoke is used as described above,
In order to reduce the leakage magnetic flux from the magnetic pole formed by the plate-shaped rare earth magnet, it is preferable to form a groove in the inner peripheral portion of the yoke located between the plurality of rare earth magnets. This groove is preferably formed to have a width dimension substantially equal to the interval between the plurality of rare earth magnets.

The above-mentioned groove may be provided so as to extend in the axial direction of the flywheel, but it is preferable to provide the groove at a certain angle (skewed state) with respect to the axial direction of the flywheel. You may. When the grooves are skewed, reduction of noise caused by rotation of the flywheel can be expected.

When the grooves are provided along the axial direction of the flywheel, the profile of the plate-shaped rare-earth magnet is rectangular (actually, curved so as to form a part of a cylindrical surface along the circumferential direction of the flywheel). However, when the grooves are skewed, the contour of the plate-shaped rare-earth magnet becomes a parallelogram.

For safety, a cover for covering a rotating part is usually attached to an internal combustion engine drive welding machine. The cover is formed so as to cover the flywheel, the flywheel side surface of the crankcase of the internal combustion engine, and a part of the cylinder of the engine, and the flywheel covers a part of the cylinder of the internal combustion engine. An air outlet having an exhaust port opened on the opposite side to the arranged side and having an air introduction hole in a portion facing the bottom wall of the flywheel can be used.

When the cover is provided in this manner, a blower blade that rotates together with the flywheel and blows radially outward is provided outside the bottom wall portion of the flywheel, and the generator and the engine are mounted inside the cover. An air flow for cooling is generated.

The blower blades may be formed integrally with the flywheel, or may be formed separately from the flywheel.

[0052]

1 shows an example of the configuration of an internal combustion engine drive welding machine according to the present invention. In FIG. 1, reference numeral 1 denotes an internal combustion engine, 2 denotes a magnet driven by the internal combustion engine 1, 3
0 is a welding generator, 5 is a cover for covering the magnet 2 and a part of the internal combustion engine 1, 6 is an ignition device for the internal combustion engine, and 7 is an internal combustion engine starting device.

The internal combustion engine 1 is the same as that shown in the conventional example shown in FIG. 6, and is disposed so as to cross the inside of the crankcase 1a, the cylinder 1b, and the crankcase 1a via a bearing. A crankshaft 1c supported by a crankcase and a connecting rod 1 fitted in a cylinder 1b
piston 1e connected to the crankshaft 1c
And a spark plug 1f attached to the cylinder head, and only one end 1c1 of the crankshaft 1c is led out.

The magneto 2 is a flywheel magnet rotor 2 attached to one end 1c1 of the crankshaft of the internal combustion engine 1.
A and an ignition firing 2B fixed to the internal combustion engine.

The flywheel magnet rotor 2A includes a cup-shaped cast iron flywheel 201 integrally including a peripheral wall 201a and a bottom wall 201c on which a boss 201b for attaching a rotating shaft is formed. Magnet mounting recess 201 formed on the outer peripheral portion of peripheral wall portion 201a
and permanent magnets 204 for ignition disposed in the flywheel with bolts 203 together with the pole pieces 202
It consists of One end 1c1 of the crankshaft of the internal combustion engine is inserted into a tapered hole provided in the boss 201b of the flywheel.
The tapered portion formed at the end is fitted to one end 1 of the crankshaft.
A nut 9 is screwed into a screw portion formed at the tip of c1. By tightening the nut 9, the flywheel magnet rotor 2A is connected to the crankshaft 1c.

The permanent magnet for ignition 204 is made of a ferrite magnet, and a magnetic pole (for example, an S pole) on the opposite side of the pole piece 202 of the permanent magnet 204 is led out to the outer peripheral portion of the hula wheel on both sides of the magnet mounting recess 201d. , These poles,
Depending on the magnetic pole (for example, N pole) appearing on the pole piece 202, 3
A pole ignition magnet field is configured.

The ignition generator 2B includes an ignition permanent magnet 20
4, an ignition core 20 having a magnetic pole part facing the ignition magnet field formed on the outer periphery of the flywheel 20
5 and an ignition coil 206 wound around the iron core. The ignition core 205 is fixed to a mounting portion 1g protruding from a cylinder of the engine by a bolt 207.

The ignition coil 206 is composed of a primary coil and a secondary coil concentrically wound around an iron core 205.
The primary coil of the ignition coil is connected to the ignition unit 208. The ignition coil 206 and the ignition unit 208 constitute the ignition device 6 for an internal combustion engine.

In this example, the primary coil of the ignition coil 206 also serves as an ignition power supply coil, and an AC voltage is induced in the primary coil in synchronization with the rotation of the engine. The ignition unit 208 controls the current flowing through the primary coil of the ignition coil 206 to generate a rapid change in the current at the ignition timing of the engine, thereby generating a high voltage for ignition in the secondary coil of the ignition coil. . The high ignition voltage obtained from the ignition coil 206 is applied to the ignition plug 1f through a high-voltage cord (not shown).

The cover 5 includes a peripheral wall 501 and a bottom wall 502
And is formed so as to cover the magnet 2, the magnet side surface of the crankcase 1 a of the internal combustion engine, and a part of the cylinder 1 b of the engine. The cover 5 has an exhaust port 5 a that opens on the side opposite to the side on which the magnet is disposed at a portion that covers a part of the cylinder 1 b of the internal combustion engine, and a bottom wall portion 502 that faces the bottom wall portion 201 c of the flywheel 201. Has an air inlet 5b.

A cup-shaped driven member 7a constituting a part of the internal combustion engine starting device 7 is fixed to the outer surface of the bottom wall 201c of the flywheel 201. A case 7b of a starter formed in a cup shape is fixed around the air inlet 5b of the cover 5, and a drive mechanism 7c is provided inside the case 7b.
Is attached.

The illustrated internal combustion engine starting device 7 is a known recoil device having a structure for transmitting the rotation of a drive mechanism 7c generated by pulling a rope 7d to a crankshaft 1c of the engine via a driven member 7a and a flywheel 201. When the rope 7d is pulled by the starter and the driving mechanism 7c is rotated, the clutch pawl is projected from the driving mechanism 7c, and the clutch pawl is engaged with the clutch pawl engaging hole provided in the driven member 7a. This causes the crankshaft 1c to rotate.

Although the recoil starter is used as the internal combustion engine starting device 7 in the illustrated example, an electric starter may be used instead of the recoil starter, and both the manual start and the electric start are performed. An internal combustion engine starting device that can be used (for example, one in which the illustrated driving mechanism 7c can also be driven by an electric motor) may be used.

A magnet field 31 for the welding generator is formed on the inner periphery of the peripheral wall 201a of the flywheel 201. The magnet fields 31 are arranged at predetermined intervals in the circumferential direction of the flywheel and fixed to the flywheel by bonding or the like, and are n pieces (n is an even number of 2 or more) having the same size and shape. ) Is composed of the plate-shaped rare earth magnet 36. In the illustrated example, there are provided 16 rare-earth magnets 36 whose contours are rectangular and which are curved so as to form part of a cylindrical surface along the inner periphery of the peripheral wall of the flywheel.
By bonding these rare earth magnets to the inner circumference of the peripheral wall of the flywheel, a 16-pole magnet field 31 for the welding generator is formed on the inner circumference of the peripheral wall of the flywheel. The magnet rotor 3 for the welding generator is composed of the flywheel 201 and the magnet field 31 for the welding generator consisting of the rare earth magnet.
0A is configured.

Inside the flywheel 201, there are m pieces (m) opposed to the magnet field 31 composed of a rare earth magnet.
Is a weld made of an annular star-shaped iron core having an even number of 2 or more (m = 24 in the illustrated example) (an iron core in which m salient poles project radially from the outer periphery of an annular yoke). A welding generator armature 30B including a generator armature core 32 and a power generating coil 33 wound around the armature core 32 and connected in three phases is arranged. The core 32 of the armature 30B is Mounting portion 1h projecting from crankcase 1a of internal combustion engine 1
Are fastened by bolts (not shown). The welding generator 30 is constituted by the magnet rotor 30A for the welding generator and the armature 30B.

Since the rare earth magnet has a very large holding force,
A large amount of magnetic flux can be generated by a small plate-shaped magnet having a small thickness. Therefore, when the magnet field of the magnet generator is configured using the rare earth magnet as described above, a flywheel 201 having the same size as that conventionally used as the flywheel 201 is used. Without increasing the size, it is possible to obtain an output more than twice the output obtained from a conventional magnet generator using a ferrite magnet, and to generate sufficient and necessary power to drive the welding load. Obtainable.

Although a rare earth magnet is more expensive than a ferrite magnet, if the welding generator is constituted by a magnet generator, the structure becomes simple. Therefore, even if the price of the rare earth magnet is included in the calculation, the rotating field magnet type can be used. Compared to the case of using a synchronous generator, the price of the welding generator can be significantly reduced.

A blower 201e is integrally formed on the outer surface of the bottom wall 201c of the hula wheel 201, and an air inlet 7e is formed on the side wall of the case 7b of the starter. The blower blade 201e sends out the air taken in from the air inlet 7e in the centrifugal direction to generate a flow of cooling air in the cover 5. Part of the air sent in the centrifugal direction by the blower blades 201e flows as shown by the arrow C, flows toward the cylinder 1b of the engine while cooling the ignition generator 2B and the ignition unit 208, and cools the cylinder 1b. And is discharged to the outside through the exhaust port 5a. The other part of the air sent in the centrifugal direction by the blower blade 201e is, as shown by the arrow D in the drawing, the flywheel 201 and the crankcase 1 of the engine.
The air is discharged from the exhaust port 5a to the outside while cooling the armature 30A and the internal combustion engine through the gap between the armature 30A and the internal combustion engine.

FIG. 5 is a block diagram showing the overall structure of the welder for driving an internal combustion engine shown in FIG. 5. In FIG. 5, reference numerals 2 and 30 denote a magnet and a welding generator driven by the internal combustion engine 1, respectively. Is an ignition unit connected to the ignition generator 2B of the magneto 2. Welding generator 3
The three-phase AC output obtained from 0 is supplied to the welding load consisting of the arc welding torch 15 and the base material 16 through the control rectifier 14. Further, in this example, part of the output obtained from the welding generator 30 is input to the regulator 11 having a rectifying function and a voltage adjusting function, and a charging current is supplied from the regulator 11 to the battery 12.
The output of the battery 12 is input to a power terminal of the control unit 17. The control unit 17 includes the welding generator 30
And the phase of the control rectifier 14 is controlled so that the welding current supplied from the welding machine to the welding load is maintained at a set value. When an electric starter is used as the starting device 7 for the internal combustion engine, a starter motor 18 of the starting device is used.
Is supplied with the output of the battery 12.

As described above, in the internal combustion engine drive welding machine of the present invention, since the generator only needs to be disposed at one end of the crankshaft of the internal combustion engine, it is apparent from a comparison between FIG. 1 and FIG. In addition, the axial dimension of the welding machine can be significantly reduced. Also, since it is not necessary to use a large flywheel, it is possible to reduce the size and weight of the internal combustion engine drive welding machine.

In a conventional welding machine driven by an internal combustion engine, a field rotating synchronous generator used as a welding generator was expensive. However, in the present invention, a magnet generator is used as the welding generator to generate the electric power. Since the price of the welding machine can be reduced, the price of the welding machine can be reduced.

Further, when the generator is arranged only at one end of the crankshaft of the internal combustion engine as in the present invention, the blower blade for cooling the internal combustion engine and the generator is provided at one end of the crankshaft of the engine. (In the example shown, the bottom wall of the flywheel)
, The cooling structure can be simplified, windage loss can be reduced, and power generation efficiency can be increased.

In the example shown in FIG. 1, only one end 1c1 of the crankshaft 1c of the internal combustion engine is led out. However, the other end of the crankshaft 1c is also led out and the other end of the crankshaft 1c is drawn out. A load other than the generator may be connected to the power supply.

FIGS. 2 to 4 show preferred examples of the structure of the magnet 2 and the welding generator 30 used in the present invention. The illustrated flywheel 201 is formed such that a main portion thereof has a substantially cup-like shape, a boss portion 201b is formed at the center of a bottom wall portion 201c, and a ventilation window 201j is provided around the boss portion 201b. Is formed. A large number of blowing blades 201e are formed in a portion near the outer periphery of the bottom wall portion 201c of the flywheel 201.

A thick portion 201a1 extending over the entire circumferential direction of the flywheel is formed at a portion near the bottom wall portion 201c of the peripheral wall portion 201a of the flywheel 201, and a magnet is attached to a part of the thick portion 201a1. 201d is formed. One magnetic pole surface of a permanent magnet (ferrite magnet) 204 is in contact with the bottom of the magnet mounting recess 201d via an adhesive, and the magnetic pole piece 202 is formed on the other magnetic pole surface of the permanent magnet 204 via an adhesive. Has been abutted. Magnetic pole piece 20
2 and the permanent magnet 204 are passed through and the bolt 203 is screwed into the peripheral wall portion 201a.
The adhesive applied between the permanent magnet 204 and the bottom surface of the magnet mounting concave portion 201d and between the permanent magnet 204 and the pole piece 202 causes the permanent magnet 204 and the pole piece 202
Are fixed to the flywheel 201. Flywheel 201, permanent magnet 204 and pole piece 202
Constitutes the hula wheel magnet rotor 2A of the magnet 2, the permanent magnet 204, the pole piece 202 and the recess 201.
A three-pole ignition magnet field is constituted by the outer periphery of the flywheel on both sides of d.

The signal emission 2B has a magnetic pole 205 at both ends.
a, 205a, and an ignition coil 206 wound around the core. The ignition coil 206 includes a primary coil and a secondary coil,
The whole is covered with a resin mold part 206a. A high-voltage cord connection portion 206a1 is provided at a portion near the outer periphery of the resin mold portion 206a, and a high-voltage cord 2 having a terminal portion of the secondary coil connected to the high-voltage cord connection portion 206a1.
1 is connected to a spark plug (not shown). The primary coil of the ignition coil is connected to the ignition unit through a lead wire (not shown) drawn from the resin mold portion 206a.

The ignition generator 2B is fixed to a mounting portion provided in a cylinder of the internal combustion engine by screws inserted into mounting holes 205b formed at both ends of the iron core 205, and the magnetic pole portions 205a, 205a at both ends of the iron core 205 are provided. 205a is opposed to the thick portion 201a1 of the hula wheel via a gap.

The above flywheel magnet rotator 2A
It is attached to the crankshaft of an internal combustion engine and is driven to rotate by the engine. When the flywheel magnet rotor 2A rotates, the magnetic field for ignition formed on the outer periphery of the thick portion 205a1 of the flywheel becomes the magnetic pole portions 205a, 2a of the iron core 205.
Since the magnetic flux changes in the iron core 205 when passing through the position 05a, an AC voltage is induced in the primary coil of the ignition coil 206. The ignition unit (not shown) controls the current flowing in the primary coil of the ignition coil by this AC voltage to induce a high voltage for ignition in the secondary coil of the ignition coil.

The welding generator 30 includes a flywheel 201
And an n-pole (n is an even number of 2 or more) welding generator magnet field 31A formed on the inner periphery of the peripheral wall portion 201a of the flywheel.
And an armature core 32 for an m-pole (m is an even number of 2 or more) fixed to the internal combustion engine having a magnetic pole portion facing the magnet field for the welding generator inside the flywheel. And a welding generator armature 30B constituted by a welding power generating coil 33 wound around the armature core.

The magnet field 31 for the welding generator is arranged side by side at equal angular intervals on the inner periphery of the yoke 35 and a yoke 35 made of a magnetic material having better magnetic properties than the cast iron constituting the flywheel. It is made of n (n is an even number of 2 or more) rectangular rare earth magnets 36 having the same size and shape and fixed to the yoke by bonding. Rare earth magnet 3 on inner periphery of yoke 35
6, 36,..., The portions extending between the magnets extend in the axial direction of the yoke, and the width W of the opening is determined by the distance between the magnets (between adjacent ends of the adjacent rare earth magnets 36, 36). Are formed substantially equal to (interval).

A magnetic material having better magnetic properties than cast iron is a material that can flow more magnetic flux than cast iron and has less iron loss, that is, a material having a saturation magnetic flux density and magnetic permeability higher than that of cast iron. It means a magnetic material that is high and has low holding power.

The illustrated yoke 35 is connected to the flywheel 20.
1 is formed by laminating a predetermined number of silicon steel sheets punched into an annular shape to fit into the inner periphery of the peripheral wall portion with almost no gap, and is press-fitted to the inner periphery of the peripheral wall portion 201a of the flywheel 201. To the flywheel.

On the inner periphery of the yoke 35, there are n (n = 16 in the illustrated example) grooves 37, 3 arranged at equal angular intervals in the circumferential direction.
7,... Are formed. In the illustrated example, each groove 37 is formed so as to extend in the axial direction of the yoke 35, and the width W of the opening is determined by the gap between the rare-earth magnets disposed on the inner periphery of the yoke. It is set almost equal to the width dimension. The n magnet mounting bases 38, 38, 38,... Of the same shape arranged at equal angular intervals along the circumferential direction of the yoke by the portions located between the grooves 37, 37,.
Are formed.

Each rare earth magnet 36 has the same thickness,
The magnet mounting base 38 is formed in the shape of a plate having substantially the same outline (in the illustrated example, a rectangle) as the outline of the inner surface of each magnet mounting base 38, and one rare earth magnet 36 is bonded to the inner surface of each magnet mounting base 38 It is fixed by.

The n rare earth magnets 36 fixed to the inner periphery of the yoke 35 are magnetized alternately in different directions of magnetization, and are magnetized by these rare earth magnets in the circumferential direction of the flywheel 201. N poles and S poles are alternately arranged along
A magnet field 31 for the welding generator of the pole is formed.

The rare earth magnet 36 may be magnetized after being attached to the inner peripheral surface of the yoke 35 if possible.
When magnetizing the rare earth magnet 36, a strong magnetizing energy is required, and a large magnetizer is required for the magnetizing. Therefore, the magnet is magnetized after attaching the rare earth magnet to the inner periphery of the yoke 35. It is often difficult. Therefore, it is preferable that the rare-earth magnet 36 is magnetized before being attached to the inner periphery of the yoke.

The armature core 32 for the welding generator has an annular yoke portion 32a and m pieces (m = 24 in the illustrated example) projecting from the outer peripheral portion of the yoke portion 32a at equal angular intervals in the radial direction. Are formed by inserting a coil conductor into a slot formed between the salient pole portions 32b, 32b,...
The welding power generation coil 33 is wound around b. The armature core 32 is disposed inside the flywheel 201 with the center axis shared with the flywheel 201, and the magnetic pole formed at the tip of the salient poles 32b of the armature core 32 is used for welding power generation. It faces the machine magnet field 31 via a predetermined gap.

As in the above example, rare-earth magnets 36, 36,... Are attached to the inner periphery of an annular yoke 35 made of a laminate of steel sheets having better magnetic properties than cast iron.
Is fixed to the inner circumference of the peripheral wall of the flywheel 201 to form the magnet field 31 for the welding generator on the inner circumference of the flywheel. Path of the magnetic flux generated from the rare earth magnet (yoke 35)
Can reduce the magnetic resistance, so that the power generation performance can be improved.

Since the rare earth magnet 36 has a small thickness,
At both ends in the width direction, leakage magnetic flux easily flows from the N pole to the S pole. When the leakage magnetic flux increases, the amount of magnetic flux linked to the power generation coil decreases, and the power generation performance decreases. In the above example, a groove 37 having a width substantially equal to the width W of the gap formed between the rare-earth magnets is formed in a portion located between the rare-earth magnets on the inner periphery of the yoke 35 so that each rare-earth magnet is formed. By increasing the magnetic resistance of the leakage magnetic path formed at both ends in the width direction, the amount of leakage magnetic flux is reduced and the power generation performance is improved.

In the above example, the ignition coil 206 composed of a primary coil and a secondary coil is wound around the ignition core 205, so that the primary coil of the ignition coil also serves as the ignition power supply coil. The ignition generator 2B may have an ignition power supply coil, and the ignition coil may be provided outside the magneto to generate the ignition generator core 205B.
, Only the ignition power supply coil may be wound.

In the example shown in FIGS. 2 to 4, the yoke 3
5 is press-fitted to the inner periphery of the peripheral wall of the flywheel, but the yoke 35 may be fitted and fixed to the inner periphery of the peripheral wall of the flywheel. And fixed to the flywheel by bonding.

In the above example, the flywheel is made of cast iron. However, the present invention can be applied to a case where a flywheel manufactured by drawing an iron plate is used. When using a flywheel formed by drawing, if an iron plate having good magnetic properties is used as a material for the flywheel, the flywheel can be fitted without fitting a yoke to the inner periphery of the peripheral wall of the flywheel. Even if a structure in which a rare earth magnet is directly adhered to the inner periphery of the peripheral wall portion is used, the same power generation performance as when the yoke 35 is provided as shown in FIG. Even when using a flywheel drawn by using an iron plate having good magnetic properties, if the thickness of the peripheral wall of the flywheel is small, an annular yoke is fitted and fixed to the inner periphery of the peripheral wall of the flywheel. Thus, it is preferable to adopt a structure in which a rare earth magnet is bonded to the inner periphery of the yoke.

In the above example, an ignition permanent magnet is attached to the outer periphery of the flywheel to constitute an ignition magnet field, and an ignition electromotive force is provided opposite the ignition magnet field to provide a magnet 2 Is configured to obtain a voltage for driving the ignition device for the internal combustion engine. However, the voltage used for welding to the armature core of the welding generator 30 and the voltage for driving the ignition device for the internal combustion engine are obtained. The magnets may be omitted by winding the power generating coil for welding and the power generating coil for driving the ignition device, respectively, which generate the magnetic field.

The "voltage for driving the ignition device for the internal combustion engine" means a voltage used in some form for operating the ignition device for the internal combustion engine, and is applied directly to the ignition device for the internal combustion engine as a power supply voltage. It is not limited to the voltage applied. For example, when an internal combustion engine igniter that operates using a battery as a power source is used, the voltage used to charge the battery is “voltage for operating the internal combustion engine igniter”.

In the example shown in FIGS. 2 and 3, the yoke 3
A groove 37 extending in the axial direction of the flywheel is formed in a portion located between the rare earth magnets 36, 36,... On the inner peripheral portion of the flywheel 5 in a direction inclined with respect to the axial direction of the flywheel. May be provided (in a skewed state). When the groove 37 is skewed,
A plate having a parallelogram contour is curved to form a part of a cylinder along the inner circumference of the peripheral wall of the flywheel, and a rare earth magnet 36 is attached to the inner circumference of the yoke 35 to generate welding power. The magnet field 31 is constituted.

In the above example, the blower wings 201e are formed integrally with the bottom wall of the flywheel. However, the blower wings are formed separately from the flywheel, and the blower wings are fixed to the flywheel by appropriate means. You may make it.

[0097]

As described above, according to the present invention, since the generator is arranged only at one end of the crankshaft of the internal combustion engine, the blower for cooling the internal combustion engine and the generator is provided with the engine. Only on one end of the crankshaft. Therefore, not only the cooling structure can be simplified, but also the windage loss caused by the blowing blades can be reduced as compared with the conventional case, and the power generation efficiency can be increased.

Further, according to the present invention, the magnet generator constructed using the flywheel attached to one end of the crankshaft of the internal combustion engine is used as the welding generator, so that both ends of the crankshaft of the internal combustion engine are used. Compared to a conventional internal combustion engine drive welding machine to which a generator is attached, the axial dimension of the welding machine can be greatly reduced, and the size and weight of the welding machine can be reduced.

Further, in the present invention, an annular yoke made of a magnetic material having good magnetic properties is fitted and fixed to the inner periphery of the peripheral wall portion of the flywheel, and welding is performed by attaching a rare earth magnet to the inner periphery of the yoke. When the magnet field for a generator is configured, the amount of magnetic flux flowing through the magnetic path of the magnet field can be increased, and iron loss can be reduced. By utilizing this, high power generation performance can be obtained.

Further, in the present invention, when grooves are formed in the inner peripheral portion of the yoke for mounting the rare earth magnets at portions located between the magnets, the leakage magnetic flux generated at both ends in the width direction of each rare earth magnet is reduced. Therefore, the amount of magnetic flux interlinked with the welding power generation coil can be increased, and power generation performance can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration example of an internal combustion engine drive welding machine according to the present invention.

FIG. 2 is a front view showing a preferred configuration example of a magnet and a welding generator used in the welding machine according to the present invention.

FIG. 3 is a sectional view of the generator of FIG. 2;

FIG. 4 is a rear view of the generator of FIG. 2;

FIG. 5 is a block diagram showing an overall configuration of a welding machine according to the present invention.

FIG. 6 is a cross-sectional view illustrating a configuration of a conventional internal combustion engine drive welding machine.

FIG. 7 is a block diagram showing an overall configuration of a conventional internal combustion engine drive welding machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Magneto 2A Flywheel magnet rotor 2B Ignition generator 201 Flywheel 204 Permanent magnet 201e Blower blade 30 Welding generator 30A Welding generator magnet rotor 30B Welding generator armature 31 Welding generator magnet Field 32 Armature iron core for welding generator 33 Generator coil for welding 35 Yoke 36 Rare earth magnet 37 Groove

Claims (6)

[Claims] A flywheel having an internal combustion engine, a peripheral wall portion and a bottom wall portion having a boss portion for attaching a rotating shaft, the boss portion being coupled to a crankshaft of the internal combustion engine; A magnet field formed on the inner circumference of the peripheral wall of the flywheel; an armature core having a magnetic pole portion facing the magnet field inside the flywheel; and a coil wound around the armature core for welding. A power generating coil for welding and a power generating coil for driving the ignition device for generating a voltage to be used and a voltage for driving the ignition device for the internal combustion engine, respectively, wherein the permanent magnet constituting the magnet field is made of a rare earth magnet. Internal combustion engine drive welding machine. 2. An internal combustion engine, comprising: a peripheral wall portion made of a magnetic material and a bottom wall portion on which a boss portion for attaching a rotating shaft is formed, wherein the boss portion is coupled to a crankshaft of the internal combustion engine. A flywheel, a magnet field formed on an inner periphery of a peripheral wall portion of the flywheel, an armature core having a magnetic pole portion facing the magnet field inside the flywheel, and the armature core. A power generating coil for welding and a power generating coil for driving the igniter, which respectively generate a voltage used for welding and a voltage for driving the igniter for the internal combustion engine, wherein the magnet field controls the flywheel. An annular yoke made of a magnetic material having a higher saturation magnetic flux density and magnetic permeability than the constituent magnetic material and having a small holding force and fitted and fixed to the inner periphery of the peripheral wall portion of the flywheel; Internal combustion engine driven welder consists rare earth magnet fixed to the yoke are arranged at equal angular intervals. 3. An internal combustion engine, a magneto for generating a voltage for driving an ignition device for igniting the internal combustion engine, and a welding generator driven by the internal combustion engine for generating a voltage used for welding, The magneto is a cast iron flywheel having a peripheral wall portion and a bottom wall portion on which a rotating shaft mounting boss portion is formed, and the boss portion is coupled to a crankshaft of the internal combustion engine; and A permanent magnet for ignition fixed to the outer peripheral portion of the peripheral wall portion; an ignition core for ignition having a magnetic pole portion opposed to a magnetic field for ignition formed on the outer peripheral portion of the flywheel by the permanent magnet for ignition; An internal combustion engine drive welding machine comprising: an ignition power supply coil wound around an ignition power generation core; and an ignition power generation fixed to the internal combustion engine. A magnet field for the welding generator formed on the inner periphery of the peripheral wall of the eel, and a magnetic pole part facing the magnet field for the welding generator inside the flywheel and fixed to the internal combustion engine. And a permanent magnet forming the welding generator magnet field is a rare earth element. The welding generator armature core is provided with a welding generator coil wound around the welding generator armature core. Internal combustion engine drive welding machine consisting of magnets. 4. An internal combustion engine, a magneto for generating a voltage for driving an ignition device for igniting the internal combustion engine, and a welding generator driven by the internal combustion engine for generating a voltage used for welding, The magneto is a cast iron flywheel having a peripheral wall portion and a bottom wall portion on which a rotating shaft mounting boss portion is formed, and the boss portion is coupled to a crankshaft of the internal combustion engine; and An ignition electrogenic core having an ignition permanent magnet attached to the outer periphery of a peripheral wall portion, a magnetic pole portion opposed to an ignition magnet field formed on the outer periphery of the flywheel by the ignition permanent magnet, and the ignition An internal combustion engine drive welding machine comprising: an ignition power source coil wound around a power generation electromotive core; and an ignition power generation source fixed to the internal combustion engine. An n-pole (n is an even number equal to or greater than 2) magnetic field for a welding generator formed on the inner periphery of the peripheral wall of the wheel, and a magnetic pole portion facing the magnetic field for the welding generator inside the flywheel. And an armature core for a welding generator comprising an annular star core having m poles (m is an even number of 2 or more) fixed to the internal combustion engine, and wound around the armature core for the welding generator. The welding generator magnetic field has a higher saturation magnetic flux density and magnetic permeability than the cast iron constituting the flywheel, and is made of a magnetic material having a small coercive force. An annular yoke fitted and fixed to the inner periphery of the peripheral wall of the flywheel, and n plate-shaped rare earth magnets arranged at equal angular intervals on the inner periphery of the yoke and fixed to the yoke. Internal combustion engine driven welding machine. 5. An internal combustion engine, a magneto for generating a voltage for driving an ignition device for igniting the internal combustion engine, and a welding generator driven by the internal combustion engine for generating a voltage used for welding, The magneto is a cast iron flywheel having a peripheral wall portion and a bottom wall portion on which a rotating shaft mounting boss portion is formed, and the boss portion is coupled to a crankshaft of the internal combustion engine; and An ignition electromotive core having a permanent magnet for ignition attached to an outer peripheral portion of a peripheral wall portion, and a magnetic pole portion facing a magnetic field for ignition formed on an outer peripheral portion of the flywheel by the permanent magnet for ignition; An internal combustion engine drive welding machine comprising: an ignition power generation coil wound around an ignition power generation core; and an ignition power generation fixed to the internal combustion engine. An n-pole (n is an even number greater than or equal to 2) magnetic field for a welding generator formed on the inner periphery of the peripheral wall of the y-wheel, and a magnetic pole inside the flywheel facing the magnetic field for the welding generator. An armature core for a welding generator having an m-pole (m is an even number greater than or equal to 2) fixed to the internal combustion engine, the armature core being for a welding generator, and a winding wound around the armature core for the welding generator. The welding generator magnetic field is formed by rotating the welding generator coil, and the welding generator magnet field is formed by a laminate of magnetic material plates having a higher permeability and a smaller holding force than cast iron constituting the flywheel. An annular yoke fitted and fixed to the inner periphery of the peripheral wall of the flywheel, and n plate-shaped rare earth magnets arranged at equal angular intervals on the inner periphery of the yoke and fixed to the yoke. Wherein the yoke is positioned between the n rare earth magnets. Internal combustion engine drive welding machine having a groove in a portion to be welded. 6. A portion formed to cover the flywheel, a surface of the crankcase of the internal combustion engine on the flywheel side, and a part of a cylinder of the engine, and a part covering a part of a cylinder of the internal combustion engine. A cover having an exhaust port opened on the side opposite to the side where the flywheel is arranged, and a cover having an air introduction hole in a portion facing the bottom wall of the flywheel is attached to the internal combustion engine, and together with the flywheel The internal combustion engine drive welding machine according to any one of claims 1 to 5, wherein a blower blade that rotates and blows radially outward is provided outside a bottom wall portion of the flywheel.