JPH0218361B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electrical heating device used for preheating as a pretreatment when remelting and hardening the surface of an iron-based member, for example.

(Prior art) It is possible to re-melt the cam lift part of a camshaft using a plasma arc, etc., and then rapidly cool the re-melted part to chill it, thereby increasing the hardness of the surface of the cam lift part and improving its wear resistance. Conceivable.

In this way, in order to remelt a part of the camshaft using plasma arc or the like, it is necessary to preheat the camshaft to about 200 to 450 degrees Celsius.
This is necessary for uniform melting and efficiency.

Generally, an electrical heating device is used for such preheating. A pair of these current heating devices are prepared, and each is attached to the rod of the cylinder unit, and both ends of the camshaft are held by the operation of the cylinder unit, and in this state, the conductive member in the current heating device is brought into contact with the camshaft to energize it. , and is heated by this energization.

(Problems to be Solved by the Invention) In the above-mentioned electrical heating device, in order to bring the electrically conductive member into contact with the camshaft, the rod of the cylinder unit to which the electrical heating device is attached is made to protrude in the direction of the camshaft. When the length of the camshaft is changed, the amount of protrusion of the rod is changed accordingly.

However, even camshafts of the same standard have slightly different dimensions such as length and diameter, and it is difficult to absorb these dimensional differences by adjusting the amount of protrusion of the rod of the cylinder unit, especially at the end of the camshaft. In many cases, a flange portion is formed, and if the dimensions of the stepped portion formed by this flange portion differ, uniform heating may not be possible.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention is an electrical heating device that heats the member to be processed by holding both end faces of the member to be processed and applying electricity. A holding member that slidably holds the member is detachably attached to the cylindrical body in the axial direction of the cylindrical body, which includes a resilient member that presses the conductive member against the end face side of the member to be processed. Further, at least the conductive member is provided with a conductive plate made of a material that does not easily oxidize, such as a silver plate, which comes into contact with the end face of the member to be processed.

More specifically, a flange portion is formed near the end surface of the member to be processed, and the holding member is provided with the conductive plate that comes into contact with the end surface of the flange portion.

(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 according to the present invention, and FIG. 2 is a front view of the same apparatus. FIG. 3 is a plan view of the same apparatus. The remelting and hardening apparatus 1 has a frame 2 erected on the floor, a support box 3 containing a power supply etc. is fixed to this frame 2, and a A control box 4 is disposed above the control box 4, a cooling device 5 is disposed above the control box 4, and plasma power supply boxes 6, 6 are disposed on the left and right sides of the 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 rotary 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, for example, 120 degrees in response to 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 middle 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 clamping mechanism 11
The rotation 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 tip of the rod 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 the 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. 8, 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.

As shown in FIG. 4, this energization heating device 32 includes a cylindrical main body 33, a piston body 34 slidably disposed within the cylindrical main body 33, and a holding member that holds the end of the workpiece W. 35 and a conductive member 36 that comes into contact with the end surface of the workpiece W, and the cylindrical main body 33 has a first cylindrical body 33a and a second cylindrical body 33b.
and a third cylindrical body 33c, the first cylindrical body 33
a is fixed to the distal end surface of the rod 31 with a bolt 38 via an insulating material 37, and this first cylindrical body 33
A second cylindrical body 33b is fixed to the front surface of
A space 40 is formed between the front surface of the cylindrical body 33a and the front surface of the cylindrical body 33a. Further, a third cylindrical body 33c is attached to the second cylindrical body 33b via a tightening member 41. That is, as shown in FIG. 5, the third cylindrical body 33c has a flange portion 42 formed in the middle thereof, and a hole 43 formed in the flange portion 42 and a hole 44 formed in the front surface of the second cylindrical body 33b. The flange of the tightening member 41 is positioned by inserting the pin 45, and by screwing the female threaded portion 46 of the tightening member 41 into the male threaded portion 47 carved on the outer periphery of the second cylindrical body 33b. Section 48
Then, the flange portion 42 of the third cylindrical body 33c is pressed against the second cylindrical body 33b and fixed.

Further, the front end of the third cylindrical body 33c has an enlarged portion 49.
A fixing member 50 is fixed to this enlarged portion 49 with bolts 51, and this fixing member 50 and enlarged portion 4
A flange portion 52 protruding outward of the holding member 35 is sandwiched between the holding member 9 and the holding member 35 . and holding member 3
A flange portion 53 that protrudes inward is formed at the front end of 5, and the workpiece W is disposed inside this flange portion 53.
It forms an opening into which the end of the tube is inserted.

On the other hand, the piston body 34 consists of a first piston body 34a and a second piston body 34b fixed to the tip of the first piston body 34a with a bolt 54. The rear end faces into a space 40 formed between the front surface of the first cylindrical body 33a and the rear surface of the second cylindrical body 33b. Here, a sixth cylinder is provided on the rear surface of the second cylinder 33b.
As shown in the figure, a laminate 56 of copper plates connected to a power source is attached by a bolt 55, and the intermediate portion of the laminate 56 is attached to the rear end surface of the first piston body 34a by a bolt 57.

Furthermore, a spring 58, which is a resilient member, is provided inside the first cylindrical body 33a, and this spring 58
The front end of the bolt 5 is supported by a spring seat 59, and the bolt 5 is attached to the spring seat 59.
The head 57a of No. 7 comes into contact with the head 57a.

The elastic force of the spring 58 urges the piston body 34 forward to the extent that the laminated body 56 bends, and this urging force causes the conductive member 36, which is slidably disposed within the holding member 35, to move forward. It is pressed against the end surface of the member W to be processed.

Here, a conductive plate 60 that is difficult to oxidize, such as a silver plate, is provided at the contact portion of the conductive member 36 with the end surface of the workpiece W, and an end face of the flange Wa of the workpiece W of the flange portion 53 of the holding member 35 is provided. A conductive plate 60 is also provided at the contact portion with.

FIG. 7 is a diagram showing the disassembled state of the energization heating device 32, and by removing the tightening member 41 from the second cylindrical body 33b, the conductive part composed of the holding member 35, the conductive member 36, etc., and the third The cylindrical body 33c can be easily removed from the device 32.

By detachably attaching the conductive part in this way, when the length or diameter of the workpiece W to be processed is changed, the third cylindrical body 33
c, the holding member 35, the conductive member 36, the second piston body 34b, etc. can be easily dealt with by replacing them with ones of different dimensions.

Further, the heating station _S3 includes a heating device 6.
1 is placed. The heating device 61 has a column 62 erected on the support box 3, and a pair of support plates 63, 63 spaced apart laterally are attached to the column 62.
A first motor 6 is installed outside these support plates 63, 63.
4 and the second motor 65, and further the support plate 6
A case 67 is attached between 3 and 63 via a stay.

The movable tables 68 and 69 are slidable along guide rods 71 and 71 installed laterally within the case 67.

Then, the first motor 6 is driven by a mechanism (not shown).
By driving the motor 4, the first and second movable tables 68, 69 can be moved synchronously, and by driving the second motor 65, the second movable table 68, 69 can be moved synchronously.
Only the moving table 69 can be moved.

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.

Further, a laser position detection device 85 is arranged behind the plasma torch 70, and this position detection device 85
detects the end face of the cam portion of the camshaft, which is the workpiece W to be processed, and moves the plasma torch 70 in the axial direction using a signal from the position detection device 85 so that the arc from the plasma torch 70 is accurately positioned on the cam portion. I try to let them do it.

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. 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 cylinder unit 22 of the input member 20
is activated to lower the clamp mechanism 23 diagonally downward, and both ends of the workpiece W held by the clamp mechanism 23 are held by the chuck mechanism 29 of the delivery member 26.

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 both ends of the workpiece W are held by the holding members 35 of the energizing heating device 32. Electricity is applied to the member W to be processed through the laminate 56, the piston body 34, and the conductive member 36, and the member W to be processed is
Preheat to about 200-450℃.

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 disposed 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.

Next, the plasma torches 70, 70 move up and down and left and right, so that the tips of the torches face the part of the workpiece W to be remelted. Specifically, when the workpiece W is a camshaft, the tips of the plasma torches 70, 70 are arranged to face one end of the cam lift.

Once the plasma torches 70, 70 are positioned at predetermined positions, the chuck device 86 is rotated by driving the motor 87, and the workpiece W to be processed is rotated around its axis by the rotation of the chuck device 86. A predetermined portion of the workpiece W is remelted by plasma arc from the torches 70, 70. Furthermore, the melting depth at this time is shallow;
Since only the surface portion is melted, after melting, heat is rapidly transferred to other portions than the fused portion, and the material is rapidly cooled and chilled by self-cooling, forming a portion with high hardness and excellent wear resistance.

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.

By repeating the above operations, the object to be treated is continuously remelted and hardened at the same location.

(Effects of the Invention) As described above, according to the present invention, the holding member that slidably holds the conductive member is formed into a cylinder having a built-in resilient member that presses the conductive member against the end face side of the member to be processed. The heating device is an energization heating device that is detachably attached to a cylindrical body in the axial direction of the cylindrical body, and at least the conductive member includes a conductive plate made of a material that does not easily oxidize, such as a silver plate, which comes into contact with the end surface of the member to be processed. Because of this, the holding member can be easily replaced together with the conductive member, even though the resilient member that presses the conductive member against the end face of the workpiece is built into the cylindrical body. In addition to being able to apply uniform electrical heating to the object to be processed, a conductive plate made of a material that is difficult to oxidize, such as a silver plate, that comes into contact with the end surface of the object to be processed prevents oxidation of the current-carrying contact surface during long-term use. can improve durability.

In addition, for a workpiece that has a flange formed near the end surface, a conductive plate made of a material that is difficult to oxidize, such as the silver plate, that comes into contact with the end surface of the flange part is also provided on the holding member, so that uniform processing can be achieved. Compatible with electrical heating.

[Brief explanation of drawings]

Fig. 1 is a side view of a remelting and hardening processing apparatus to which the energizing heating device according to the present invention is applied, Fig. 2 is a front view of the same device, Fig. 3 is an enlarged view of the clamp mechanism, and Fig. 4 is an energizing heating device. 5 is a cross-sectional view of A- in FIG.
6 is a view seen from the B-B direction of FIG. 4, FIG. 7 is an exploded view of the electrical heating device, and FIG. 8 is a view taken in the Z direction of FIG. 1. . In the drawings, 1 is a remelting hardening treatment device, 3 is a support box, 7 is a rotating shaft, 10 is an arm, 11, 2
3, 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, 33 is a cylindrical main body, 33a is a first cylindrical body, 33b is a second cylindrical body, 33c is a third cylindrical body,
34 is a piston body, 34a is a second piston body,
35 is a holding member, 36 is a conductive member, 41 is a tightening member, 56 is a laminate, 58 is an elastic member, 60 is a conductive plate made of a material that is difficult to oxidize such as a silver plate, 70 is a plasma torch, and S ₁ is a charging member. _S2 is a preheating station, and W is a workpiece to be processed.

Claims (1)

[Scope of Claims] 1. An electrical heating device that holds both end faces of a member to be processed and heats the member by applying current, the holding member slidably holding the conductive member being attached to the member to be processed. The cylindrical body has a built-in elastic member that biases the conductive member into pressure contact with the end face of the cylindrical body. An electrical heating device characterized by having a conductive plate made of a material that does not easily oxidize, such as a silver plate, that comes into contact with the conductive plate. 2. The electrical heating device according to claim 1, wherein a flange portion is formed near an end surface of the member to be processed, and the holding member is provided with the conductive plate that comes into contact with the end surface of the flange portion.