JPH0141686B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heating method and apparatus for heating a processed portion of a processed member such as a camshaft using a plasma torch or a TIG torch.

(Prior art) The treated part of a workpiece, such as the cam lift part of a camshaft, is remelted using plasma arc, etc., and the remelted part is rapidly cooled to chill it, increasing the hardness of the surface of the treated part. is known to improve wear resistance.

Conventionally, when performing such remelting hardening treatment on, for example, a camshaft, power is generally supplied from one or both ends of the camshaft.

(Problem to be Solved by the Invention) However, when power is supplied from one end of the camshaft using one arc gun, for example, the influence of the unidirectional magnetic field generated by the current flowing in the axial direction of the camshaft The arc bends.

For example, as shown in FIG. 8, when power is supplied from both ends of the workpiece W using one arc gun 70, if the distance to the arc gun 70 is different, the current I flows from both ends of the workpiece W. ₁ , _I2
This causes a difference in the magnetic field, causing the magnetic field to become unbalanced and causing the arc to bend.

In these cases, in order to make the arc directly downward,
There is a way to adjust the amount of power supplied to the left and right sides, but it is difficult to balance the power supplied to the arc.

Furthermore, as shown in FIG. 9, for example, when two arc guns 70a and 70b are used to supply power from both ends of the workpiece W, the arc guns 7
Currents I ₁ and I ₂ flow through the camshaft W between 0a and 70b.
Since the currents flow in opposite directions, the currents I ₁ and I ₂ cancel each other out, and no current apparently flows in the axial direction of the camshaft W between the arc guns 70a and 70b. The situation is the same as when power is supplied from one end of the processing member W, and the arc is bent and is not emitted directly below the arc gun.

If the arc is deflected without being emitted directly below, for example, when remelting a workpiece, the remelting position may shift or the remelting depth may become uneven, which may affect the precision of the remelting process. There is an inconvenience that the value decreases.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a method for heating the processing portion of the processing object using an arc from a plasma torch or the like while supplying power to the processing object. When the torch is injected toward the target part, the power supply member is always brought into contact with the target part at a position facing the arc, and when the torch moves, the power supply member is kept in contact with the target part. At the same time, the torch and the power supply member are moved together, so that continuous and uniform heat treatment can be performed even when there are a large number of parts to be treated.

(Example) Examples of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a side view of a remelting hardening processing apparatus equipped with a heating device according to the present invention, and FIG. 2 is a front view of the same apparatus. The remelting and hardening treatment apparatus 1 has a frame 2 erected on the floor, a support box 3 housing a power source etc. is fixed to the frame 2, a control box 4 is installed behind the support box, and a cooling device 5 is installed above the support box.
Further, plasma power supply boxes 6, 6 are arranged on the left and right sides of this cooling device 5.

In addition, the remelting and hardening processing apparatus 1 includes a loading and unloading station S ₁ for loading and unloading the workpiece W such as a camshaft, a preheating station S 2 for preheating the workpiece W, and a remelting station S ₂ for remelting the workpiece W. A rotating shaft 7 is disposed at an intermediate position between each of these stations S ₁ , S _{2 ,} and S ₃ . The rotating shaft 7 is rotated via a motor 8 fixed to the support box 3 and a speed reduction mechanism, and the amount of rotation is intermittently rotated by 120 degrees in accordance with a signal from the control box 4.

A case 9 having a substantially hexagonal shape when viewed from the side is provided at the center of the rotating shaft 7, and three arms 10 protrude outward from the case 9. These arms 10 are attached at a distance of 120 degrees from each other, and a clamp mechanism 11 is provided at the tip of each arm 10.

As shown in FIG.
a, 10a, and these left and right members 10
The intermediate parts of fingers 14, 15 are pivotally connected to the tips of fingers 14, 10a, and the rear ends of these fingers 14, 15 are connected to the rod 13 through links 16, 16.
By operating the cylinder unit 12 and causing the rod 13 to make a protruding movement, the fingers 14 and 15 are opened, the gripping state of the workpiece W is released, and the rod 13 is made to make a retracting movement. The fingers 14 and 15 are closed to grip the workpiece W. The tip of one finger 15 is a bifurcated portion 15 facing the workpiece W.
a, even if the fingers 14 and 15 are slightly opened, the workpiece W to be processed does not fall and is held rotatably between the bifurcated portion 15a and the finger 14, and when the fingers 14 and 15 are closed. is 3
The workpiece W to be processed is clamped at a point so that the center of the workpiece W is always kept constant. and,
By rotating the rotating shaft 7, the clamp mechanism 11
The rotational locus is arranged to approximately pass through each of the stations S ₁ , S ₂ , and S ₃ .

Further, a rail member 17 is fixed to the front surface of the upper horizontal frame 2a of the frame 2, and this rail member 1
7 is engaged with a traveling head 18. A motor 19 is attached to the traveling head 18, and this motor 1
9 causes the running head 18 to move laterally along the rail member 17 via the rack and pinion mechanism.

The traveling head 18 is provided with a loading member 20 for transporting unprocessed workpieces W to the loading/discharging station _S1 , and a discharging member 21 for discharging processed workpieces W from the loading/discharging station _S1 . The loading member 20 consists of a cylinder unit 22 fixed to the traveling head 18 and a clamp mechanism 23 provided at the rod end of the cylinder unit 22. When the cylinder unit 22 is operated, the clamp mechanism 23 moves to the loading/discharging station S. ₁
and a position above and in front of this station _S1 . Further, the dispensing member 21 is the input member 2.
0, the cylinder unit 24 is fixed to the traveling head 18, and the clamp mechanism 25 is provided at the end of the rod of this cylinder unit 24. When the cylinder unit 24 is operated, the clamp mechanism 25 is connected to the loading/discharging station _S1 . It moves up and down between the station _S1 and the position directly above it.

Further, a delivery member 26 is provided below the input/discharge station _S1 . This transfer member 26 has an intermediate portion of an arm 26a swingably attached to a flange portion 27 protruding forward from the front surface of the support box 3, and the lower end of the arm 26a is connected to a rod of a cylinder unit 28 fixed to the support box 3. However, when the cylinder unit 28 is actuated, the arm 26a swings back and forth (left and right in FIG. 1) centering on the intermediate portion. As shown in FIG. 4, which is a view taken in the Z direction of FIG. 1, a chuck mechanism 29, which is a holding mechanism, is provided at the upper end of the arm 26a. This chuck mechanism 29
consists of a cylinder unit 29a and a center 29b attached to the cylinder unit 29a, and the left and right centers 29b hold both ends of the workpiece W by causing the cylinder unit 29a to move forward. When the arm 26a swings due to the operation of the cylinder unit 28, the chuck mechanism 29 moves between the rotation locus of the clamp mechanism 11 provided at the tip of the arm 10 and the clamp mechanisms 23 and 2 at the lower ends of the input member 20 and the dispensing member 21.
I am trying to move between 5 and 5.

Furthermore, in the preheating station _S2 , as shown in FIG.
0,30 are arranged, and these cylinder units 30
An energization heating device 32 as a preheating device is attached to the tip of the rod 31.

Furthermore, a heating device 61 is arranged in the heating station _S3 .

As shown in FIG. 6, this heating device 61 includes a plasma torch 70, a torch vertically moving body 90 that moves the plasma torch up and down, and a torch that moves horizontally and horizontally that moves this vertically moving body 90 in the axial direction of the workpiece W. It includes a main body 91, a power feeding arm 92 as a power feeding member, and an arm moving unit 93 that brings the power feeding arm 92 into and out of contact with the camshaft W, and connects and disconnects the vertically movable main body 90.

As shown in FIG. 5, the torch left-right movable main body 91 has a column 62 erected on the support box 3, and a pair of support plates 6 spaced apart laterally from the column 62.
3 and 63, a first motor 64 and a second motor 65 are fixed to the outside of these support plates 63 and 63 as shown in FIG.
A case 67 is attached via a stay 66 in between.

A pair of first moving tables 68 and a second moving table 69 are provided inside the case 67, and these moving tables 6
At 8 and 69, a torch vertically movable main body 90 to which a plasma torch 70 connected to the plasma power source 6 is attached is attached. In addition, the moving tables 68, 6
Guide rods 71, 71 as guide members installed laterally within the case 67 pass through the case 9, and movable bases 68, 69 as movable bodies can slide along the guide rods 71 via linear slide bearings 72. It is said that

Further, a ball screw 73 and a spline rod 74 commonly pass through the movable tables 68 and 69, and these ball screws 73 and spline rods 74 are rotatably supported by the case 67.
One end of the spline rod 74 is connected to the drive shaft 64a of the first motor 64, and one end of the spline rod 74 is connected to the drive shaft 64a of the first motor 64.
The drive shaft 65a of the motor 65 is connected to the drive shaft 65a of the motor 65. The first ball nut 7 is attached to the ball screw 73.
5 and a second ball nut 76 are screwed together, the first ball nut 75 is fixed to the first moving table 68, and the second ball nut 76 is fixed to an inner sleeve 77 which is a rotating body. This inner sleeve 77 is rotatably fitted onto the ball screw 73 and is also rotatable through a bearing 79 with respect to an outer sleeve 78 fixed to the second moving table 69 . axial movement is restricted.

Furthermore, a gear 80 is provided at one end of the inner sleeve 77.
is fixed, and this gear 80 is meshed with a gear 81 fitted to the spline rod 74. In addition, 82 in FIG. 4 is a dust seal, and 83 is a stopper.

In the above, when the first motor 64 is driven, the ball screw 73 rotates.
3 rotates, the first ball nut 75 and the second
ball nut 76 is about to rotate. However, the first ball nut 75 is fixed to the first moving table 68, and the second ball nut 76 is fixed to the inner sleeve 77, and a gear 80 is fitted into the inner sleeve 77. motor 65 (not running at the moment)
Since the first ball nut 75 and the second ball nut 76 are meshed with a gear 81 fitted to a spline rod 74 connected to the ball nut 74, the first ball nut 75 and the second ball nut 76 do not rotate, but instead spiral along the ball screw 73. As a result, the first moving table 68 and the second moving table 69 move synchronously.

Further, when the second motor 65 is driven, the spline rod 74 rotates, and the rotation of the spline rod 74 rotates the gears 81 and 80.
This rotation causes the inner sleeve 77 and the second ball nut 76 to rotate. However, ball screw 7
3 does not rotate, the second ball nut 76 rotates and spirals along the ball screw 73, and as a result, only the second moving table 69 moves leftward or rightward.

In this way, the first and second movable tables 68, 69
Since the plasma torches 70 and 70 can be moved synchronously, the plasma torches 70 and 70 will not interfere with each other, and since only the second moving stage 69 can be moved individually, for example, the cam lift part of the camshaft can be moved simultaneously. When performing the remelting treatment at two locations, the remelting treatment can be performed efficiently even if the intervals between the cam lift portions are different in one camshaft.

Incidentally, an alloy powder supply unit 84 is mounted on the pillar 62.
is arranged so that the high hardness alloy powder from this unit 84 is supplied into the plasma arc.

On the other hand, a bracket 94 is fixed to the lower part of the torch vertically movable main body 90, and a hole 96 is formed in this bracket 94.

The arm moving unit 93 is attached to the base plate 9.
A moving table 99 is mounted on two rails 98, 98 arranged in the axial direction of the workpiece W to be processed on 7, with legs 100, 100 fixed to the lower surface of the moving table 99 slidably fitted thereon. There is.

A power supply arm 9 is provided on the front side of the moving table 99.
2 is rotatably supported on a shaft 102.

Note that the power feeding arm 92 is arranged so that, while in contact with the workpiece W, its tip is in contact with the side facing the plasma torch 70 via the workpiece W.

A contact portion 92a made of a good conductor such as silver is formed at the tip of the power supply arm 92 via an insulator 115 to act as an electrode, and the rear end is connected to a cylinder unit 103 attached to the top of the movable table 99. The plunger 103a is rotatably mounted on a shaft 104.

The power supply arm 92 also includes a power supply plate 10.
6 is attached to the power supply plate 106, and a power supply cable 107 is connected to the power supply plate 106.

Furthermore, a water passage used for cooling the power supply plate 106 is formed in the power supply plate 106, with a water inlet 108a and a water outlet 108b.
has been established.

Further, a spring 112 is provided on the front side of the movable table 99 so that the upper end thereof can be engaged with the hole 96 of the bracket 94.
The shaft 110, which is urged upward by the shaft 110, is slidably inserted therethrough. A pin 113 is implanted approximately in the center of the shaft 110 as shown in FIG. 7, and this pin 113 is engaged with the guide 114 of the power supply arm 92, so that the arm 92 swings clockwise in FIG. When this happens, the hole 96 and the shaft 110 engage, and when the arm 92 swings counterclockwise in FIG. 6, the shaft 110 comes out of the hole 96.
In this state, the contact portion 92a is brought into contact with the member W to be processed.

Note that a laser position detection device 85 is arranged behind the plasma torch 70 as shown in FIG. The plasma torch 70 is moved in the axial direction by a signal from a position detection device 85 so that the arc from the plasma torch 70 is accurately positioned on the cam portion.

Further, chuck devices 86, 86 are disposed on both sides of the heating station _S3 below the plasma torch 70, and these chuck devices 86, 86 hold both ends of the workpiece W to be processed, and also a motor 87 and a deceleration mechanism. By rotating the chuck device 86 via the chuck device 86, the workpiece W to be processed is rotated around the axis.

Next, the operation of the remelting and hardening processing apparatus 1 configured as described above will be described below. In the description, a state in which the clamp device 11 at the tip of each arm 10 does not grip the workpiece W will be explained as a starting point.

First, by driving the motor 19, the traveling head 18 is moved in the direction perpendicular to the plane of the paper in FIG. The processing member W is grasped approximately at the center, and the motor 19 is driven again to move the traveling head 18 to the center of the apparatus 1.

Next, the input member 20 and cylinder unit 22 are operated to lower the clamp mechanism 23 diagonally downward, and both ends of the workpiece W held by the clamp mechanism 23 are transferred to the chuck mechanism 2 of the transfer member 26.
Hold at 9.

Then, the cylinder unit 28 is activated and the arm 26a of the transfer member 26 swings clockwise in FIG.
The workpiece W to be processed, which is held at , overlaps the rotation locus of the clamp mechanism 11 provided at the tip of the arm 10 .
Therefore, while gripping the workpiece W with the clamp mechanism 11 provided at the tip of the arm 10, the gripping state of the chuck mechanism 29 is released, and the arm 10
The workpiece W to be processed is delivered to the clamp mechanism 11 of.

Thereafter, the rotating shaft 7 is rotated 120 degrees counterclockwise in FIG. 1, and the workpiece W to be processed is positioned at the preheating station _S2 . Specifically, the rotating shaft 7 rotates 120 degrees,
When the clamp mechanism 11 reaches the lowest position, the rotation of the rotating shaft 7 is stopped, and the workpiece W is energized via the energization heating device 32 to preheat the workpiece W to about 200 to 450°C. .

After the preheating is completed, the energization heating device 3
2 is released, and the rotating shaft 7
is again rotated 120 degrees counterclockwise in FIG. 1, and the workpiece W to be processed is positioned at the heating station _S3 .
Then, the chuck devices 86, 86 located on both sides of the heating station _S3 hold both ends of the workpiece W to be processed. Once both ends are held, the grip by the clamp mechanism 11 is loosened.

When putting the workpiece W into the heating device 61, the cylinder unit 103 shown in FIG. 92a is separated from the workpiece W, and the power supply arm 92 is placed at the position of the imaginary line.

At this time, as the power supply arm 92 swings to the position indicated by the imaginary line, the pin 111 is pushed upward, and the shaft 110 rises in the direction of arrow A.
is inserted and engaged.

From this state, the torch vertically moving body 90 is moved in the axial direction of the workpiece W by the horizontally moving torch main body 91, and the plasma torch 70 is moved onto the first part of the workpiece W to be processed. The torch vertically movable main body 90 is operated to cause the torch 70 to face the processed portion of the processed member W with a predetermined distance therebetween.

At this time, the moving table 99 of the torch vertical moving body 90 and the arm moving unit 93 is moved to the bracket 94.
Since the movable base 99 moves integrally with the torch left-right moving body 91, the power supply arm 92 is located below the torch 70.

When the cylinder unit 103 is operated and the plunger 103a is pulled in the direction of arrow D, the power supply arm 92 attached to the plunger 103a via the shaft 104 also swings to the solid line position in FIG.
The contact portion 92a of the power supply arm 92 is connected to the workpiece W.
It presses into contact with the member to be processed W at a position opposite to the torch 70 via.

At the same time, due to the swinging of the power supply arm 92, the shaft 110 is lowered in the direction of arrow B, and the engagement with the bracket 94 is released, and the lower end of the shaft 110 is attached to the base plate via the spring 112. The movable base 99 is fixed by being pressed against the movable base 97.

Therefore, while the workpiece W is being heat-treated, even if the torch 70 reciprocates up and down and left and right, the contact portion 92a of the power supply arm 92 remains in contact with the workpiece without moving up and down and left and right. Retained.

In this way, with the power supply arm 92 facing the plasma torch 70 and in contact with the workpiece W, the workpiece W is supplied with power from the power supply plate 106 to the electrode formed on the contact portion 92a of the power supply arm 92. A current flows through the plasma torch 70 through the member W, and an arc is emitted from the plasma torch 70 to the member W to be processed, thereby heating and melting the member to be processed.

At this time, the plasma torch 70 and the power supply arm 9
Since the electrodes 2 and 2 are facing each other, the current flows in the longitudinal direction of the workpiece W, so that the plasma torch 70
There is no magnetic field imbalance with respect to the center of
No arc deflection occurs.

Furthermore, after finishing heating and melting, the cylinder 10
3 into a non-operating state, the plunger 103a of the cylinder 103 is returned to the initial position, and the power supply arm 9
At the same time, the shaft 110 is raised and the bracket 94 is removed.
The movable table 99 is returned to the state connected to the torch vertically movable main body 90 by engaging with the hole 96 of the torch. As a result, the power feeding arm 92 moves together with the plasma torch 70 and is located at the part to be heated next, and when there are multiple parts to be processed on the workpiece W, the above operation is repeated. conduct.

Here, to specifically describe the remelting effect when the workpiece W is a camshaft, the tips of the plasma torches 70, 70 are faced to one end side of the cam lift, and the chuck device 86 rotates to melt the workpiece W.
While rotating the plasma torch 7 around its axis,
A predetermined portion of the member W to be processed is remelted by a plasma arc from 0.0,70°C. Furthermore, the melting depth at this time is shallow and only the surface portion is melted, so after melting, heat is rapidly transferred to other parts than the molten part, and the material is rapidly chilled by self-cooling, resulting in high hardness and wear resistance. form an excellent part.

Thereafter, the rotating shaft 7 is further rotated 120 degrees counterclockwise, and the processed workpiece W is positioned at the loading/discharging station _S1 . Then, the delivery member 26 swings clockwise, the chuck mechanism 29 of the delivery member 26 grips the processed workpiece W, and the gripping state by the clamp mechanism 11 is released, and the workpiece W is delivered. Part 2
Hand it over to 6. Next, the arm 26a of the transfer member 26 is swung counterclockwise by a predetermined angle by the operation of the cylinder unit 28, and the workpiece W to be processed is taken out of the rotation locus of the clamp mechanism 11.

When the workpiece W is taken out of the rotation locus of the clamp mechanism 11, the delivery member 21
The cylinder unit 24 is activated to lower the clamp mechanism 25 and grip the workpiece W at its lowered end. In addition, the dispensing member 21 and the inputting member 2
0 and 0 at the same time, so that they do not interfere with each other at the lower end.

In this way, after the processed workpiece W is gripped by the clamp mechanism 25 of the dispensing member 21, the cylinder unit 24 is activated to pull the workpiece upward, and the motor 19 is driven to move the workpiece W to the traveling head. The whole 18 moves and transports the processed member W to the next process or the like.

In the embodiment, a case where a TIG torch or a plasma torch is used for remelting and hardening treatment is described, but the present invention may also be applied to a case where the surface of a crankshaft or the like is hardened.

(Effects of the Invention) As explained above, according to the present invention, the power feeding member is brought into contact with the part to be treated at a position facing the plasma torch or the TIG torch, and the part to be treated is heated. Power can be supplied from the power supply member in a well-balanced manner in the axial direction, and the magnetic field generated by the power supply is balanced, so the arc is not deflected. Therefore, when remelting a member to be treated, for example, it is possible to uniformly and reliably radiate an arc to a predetermined part to be treated, thereby significantly improving the accuracy of the remelting and hardening process.

In addition, since the power supply member is linked to the torch, it is easier to position the power supply member, which improves work efficiency, especially when applying heat treatment to multiple parts of the workpiece in succession. Significantly improved.

[Brief explanation of drawings]

Fig. 1 is a side view of a remelting heat treatment device equipped with a heating device according to the present invention, Fig. 2 is a front view of the same device, Fig. 3 is an enlarged view of the clamp mechanism, and Fig. 4 is a portion of the swinging member. Figure 5 is a sectional view of the torch's left-right moving body, Figure 6 is a side view of the heating device, Figure 7 is a front view of the
The figure is a sectional view of the main part of the heating device, and FIGS. 8 and 9 are conventional examples. In the drawing, 1 is a remelting heating device, 3 is a support box, 7 is a rotating shaft, 10 is an arm, 11, 23,
25 is a clamp mechanism, 20 is a charging member, 21 is a dispensing member, 26 is a delivery member, 32 is an electric heating device, 61 is a heating device, 70 is a plasma torch,
90 is a main body for moving the torch up and down, 91 is a main body for moving the torch left and right, 92 is a power supply arm, 93 is an arm movement unit, 94 is a bracket, 103 is a cylinder unit, 106 is a power supply plate, 110 is a shaft, and S ₁ is a loading/discharging station. , S ₂ is a preheating station, S ₃ is a heating station, and W is a member to be processed.

Claims (1)

[Scope of Claims] 1. A heating method in which a plasma torch or a TIG torch is used to heat a processed portion of a processed member while supplying power to the processed member, wherein the plasma torch or
A heating method characterized in that the part to be processed is heated by bringing a power supply member into contact with the part to be processed at a position facing a TIG torch. 2. In a heating device that heats the processing target part of the processing target member using a plasma torch or a TIG torch,
This heating device includes a contact means for bringing a power supply member into contact with the workpiece at a position facing the torch when the plasma torch or TIG torch is activated, and a contact means for bringing the power supply member into contact with the workpiece at a position facing the plasma torch or the TIG torch. A heating device characterized by comprising interlocking means for interlocking the power supply member with the plasma torch or the TIG torch while releasing the contact with the plasma torch or the TIG torch.