JPS648050B2 - - Google Patents

Description

[Detailed description of the invention] (Technical field) The present invention relates to a remelting hardening treatment apparatus.

(Background Art) As a surface hardening treatment for the cam surface of a cam portion in a camshaft, remelting hardening treatment (remelt treatment) is practically used. By the way, when remelting and hardening the cam surface of each cam part, the process was performed while drawing a meandering trajectory. In the conventional method of drawing a meandering trajectory, the support table on which the object to be processed is placed is reciprocated from side to side, and the object to be processed is rotated. Therefore, in the past, mechanical means such as eccentric cams were used to achieve this, and the movement mechanism had the disadvantage of becoming large in size as a whole.

(Object of the Invention) Therefore, it is an object of the present invention to provide a torch for remelting the processed parts while only rotating the processed parts, such as a camshaft, which has a plurality of processed parts spaced apart in the axial direction. It is an object of the present invention to provide a remelting and hardening treatment apparatus that can reciprocate within an axial width to form a meandering trajectory, and in particular can sequentially remelt and harden a plurality of treated parts.

(Structure of the Invention) In order to solve the above-mentioned problems and achieve the object, the present invention rotates a workpiece having a plurality of workpieces spaced apart in the axial direction, and each workpiece of the workpiece is rotated. A rotating device that holds and rotates the object to be processed, a torch that remelts and hardens each part of the object held by the rotating device, a moving device that sequentially moves the torch to each processed portion of the processed object, and reciprocates the torch in each processed portion within the axial width of the processed portion by forward and reverse rotation of a motor; , a switch base comprising a pair of limit switches for axially opposite end positions of the to-be-treated portion and movable in parallel along the axial direction of the to-be-treated object; It is characterized by comprising a fixed positioning member having a limit switch at a position corresponding to each processing target, and a coupling means for selectively coupling the switch base to either the positioning member or the torch. shall be.

With the remelting and hardening treatment apparatus configured as described above, the torch coupled to the switch base by the coupling means is moved by the motor drive of the moving device, and when the position of the switch base matches the position of the limit switch provided on the positioning member. At the same time, the motor is stopped, the switch base is connected to the positioning member by the connecting means to release the connection with the torch, and when the position of the torch matches the position of the limit switch provided on the switch base, the motor is rotated in the forward direction. The torch is switched to the reverse direction, and the torch is reciprocated within the axial width of the processed portion, thereby sequentially forming a meandering trajectory on each processed portion by combining the rotation of the processed object with the rotating device.

(Embodiment) A preferred embodiment of the present invention will be described below based on the accompanying drawings.

First, the overall structure of the remelting and hardening treatment apparatus according to the present invention will be explained with reference to FIGS. 1, 2, and 3.

In FIGS. 2 and 3, 1 is a preheating section,
In the preheating section 1, a motor 3 having a workpiece chuck 2 in its rotating section and an axial pressing cylinder 5 having a center 4 are arranged on the front side of a table 7 of a base 6 with a certain interval. has been done. A camshaft 8 supported by the work chuck 2 and the center 4 is disposed before being subjected to the remelting and hardening process. It is heated.

The preheated camshaft 8 is transferred by a loader 10 disposed above to an adjacent processing section 11 located on the back side of the table.

The processing section 11 is a station that performs remelting and hardening processing. Also in the processing section 11, a motor 14 having a work chuck 12 for supporting and fixing the camshaft 8 via a deceleration mechanism 13, and an axial pressing cylinder 16 having a center 15 are disposed. This constitutes a rotating device. In this case, the axial pressing cylinder 16 is connected to the guide bars 17a, 17 installed on the support stand 17 on the table 7.
It is configured to be able to move to the left in FIG. 1 by being guided by a.

A support shaft 18 is provided diagonally above the camshaft 8 supported by the chuck 12 and center 15 on the back side of the table 7. This support style 18
Guide bars 19, 19 are vertically spaced apart between the left and right vertical portions 18a, 18a in FIG. The guide bars 19, 19 are inserted into the upper and lower parts of the base 21 for the plasma torch 20 for remelting and hardening treatment, and ensure that the torch 20 moves in the left and right directions in FIG. A feed screw 22 is rotatably mounted horizontally between the upper and lower guide bars 19, 19, and the feed screw 22 is screwed into the base 21 via a ball screw mechanism. Feed screw 22
is connected via a transmission mechanism 24 to a torch moving motor 23 located outside the vertical portion 18a on the left side in FIGS. 1 and 2, and is driven to rotate in forward and reverse directions by this motor 23. This constitutes a mobile device.

Further, a holder 25 for holding the plasma torch 20 is provided on the base 21 so as to be movable up and down. Therefore, a motor 21a is provided within the base 21 to move the holder 25 up and down. The plasma torch 20 held in the holder 25 has its tip facing downward, and the workpiece chuck 12 and the center 1
The camshaft 8 is disposed above the camshaft 8, which is disposed between the camshaft 5 and the camshaft 5, so that its axis is in the vertical direction.

On the other hand, on the upper side of the base 21, a guide bar 2 is further installed between the vertical portions 18a, 18a.
A limit switch base (hereinafter referred to as LS base) 27 that is movably guided in the horizontal direction by 6 and 26.
is provided. As shown in FIG. 4, this LS base 27 includes an LS base positioning pin 29 provided in a piece 28 to move up and down under control, a limit switch (hereinafter referred to as LS) 30 for making meandering amplitude, 31. The positioning pin 29 is inserted into the recess 21 formed in the upper part of the base 21.
b. Also, LS30 and 31 are base 2
It is attached so as to face the LS dock 21c attached to the top of 1. Furthermore LS base 2
7, the base 21 is located above the camshaft 8.
A member 32 for setting positioning when sequentially moving to each of the cam portions 8-1 to 8-8 is disposed. The member 32 includes each cam portion 8-1 to 8-8.
LS32a for stopping is provided correspondingly. LS dock 27a provided on base 21 is LS32
a..., and when the positioning is determined, the positioning pin 2 is inserted into the recess 32b... formed corresponding to each cam part 8-1 to 8-8.
9 is moved upward and fitted, and the position of the LS base 27 is fixed.

A nozzle portion 33 as shown in FIG. 5 is provided at the tip of the plasma torch 20. As shown in FIG. Nozzle part 33
Now, the chip 35 is arranged inside the shield cap 34, and the passage 3 for the shield gas is established between them.
6 is formed. A working gas passage 37 is formed in the center of the chip 35, and a cooling passage 38 is formed around it.
is formed. 39 is an electrode made of tungsten or the like. Further, the metal powder introduction tubes 40, 40 are connected to the shield cap 34, and the extension line of the axis thereof is the passage 37.
It is inserted and fixed so as to intersect with the extension line of. The cam portion 8-1 of the camshaft 8 is generated by the discharge by the electrode 39 of the nozzle portion 33 and the plasma of the working gas.
While forming a molten pool on the outer surface of the metal powder, a remelting and hardening process is performed by supplying metal powder from the metal powder introduction pipes 40, 40.

In FIG. 7, 41 is a plasma power supply;
The required power is supplied to the electrode 39 of the plasma torch 20. Further, 42 is a powder supply device,
While applying vibration with the vibration device 43, the pipes 44, 4
Metal powder is supplied to the metal powder introduction pipes 40, 40 through the metal powder introduction pipes 40, 40. A detection device 45 for checking the supply of powder is disposed in the middle of the pipes 44, 44.

Further, in FIG. 7, 46 is a control device.
The control device 46 has a built-in computer, and according to a pre-installed program, controls the work rotation motor 14 described above, the motor 23 that moves the torch 20 laterally, and the base 21 that positions the torch 20 vertically. A control signal for instructing the motor 21a to operate is given to the motor 21a. At the same time, drive signals for operation are also given to the plasma power source 41, powder supply device 42, and vibration device 43.

Next, a method for processing the cam portion of the camshaft 8 will be explained.

A camshaft 8 preheated in a preheating section 1 is transferred by a loader 10 and placed and fixed between a work chuck 12 and a center 15. Next, the base 21 is moved laterally by the action of the feed screw 22 by the motor 23, and the holder 25 is moved by the motor 2 inside the base 21.
Move it down with 1a. The torch 20, which was in a standby state, is held at a predetermined clearance between the nozzle part 33 and the cam surface of the first cam part 8-1 at the left end of the camshaft 8, as shown in FIG. and place it.

In such a state, the nozzle portion 3 of the torch 20
3, the cam surface of the cam portion 8-1 of the camshaft 8 is subjected to a remelting and hardening process as shown in FIG. 5 described above. In this case, the camshaft 8 is rotated at low speed by the motor 14 via the deceleration mechanism 13, while the torch 20 is rotated by the cam portion 8 in order to maintain a constant clearance between its tip and the cam surface.
The torch 20 is moved up and down in response to a height change of -1, and the torch 20 is laterally reciprocated within the width of the cam surface of the cam portion 8-1. The vertical movement of the torch 20 is performed by a motor 21a in the base 21, and the reciprocating movement thereof is performed by a motor 23 under the control of a control device.

In the above, in the initial standby state, the base 21 and the LS base 27 are connected to the pin 29 that serves as a coupling means.
are connected and integrated. When the motor 23 operates according to a command from the control device 46 and the feed screw 22 rotates, the base 21 moves to the right. At this time
The LS base 27 also moves to the right, and when the tip of the torch 20 reaches the left end position of the cam part 8-1 of the camshaft 8, the LS dock 27a and the LS 32
a acts and stops at that position. Then,
The pin 29 moves upward, releases the fitting relationship with the recess 21b of the base 21, and the upper part of the pin 29 moves up into the recess 32b.
Fits in. This allows the torch 20 to move to the cam portion 8.
-1. This is the state shown in FIG. 4, and is the starting position of the left and right reciprocating movement. Thereafter, only the base 21 starts to move to the right, and when the LS dock 21c acts on the LS 31, the rotation of the motor 23 is reversed and the base 21 moves to the left. When the LS dock 21c further acts on the LS 30, the rotation of the motor 23 is reversed again, and the base 21 is moved to the right. In this way, the torch 20 is controlled by the cam part 8-1 by the relationship between the LS 30, 31 and the LS dock 21c, and by the operation of the control device 46 which inputs this and supplies the required control signal to the motor 23. It reciprocates in the cam axis direction within the width of the cam surface. Such reciprocating motion is repeated during one rotation of the cam portion 8-1,
In this way, the remelting and hardening process is performed while drawing a meandering locus A on the cam surface of the cam portion 8-1 as shown in FIG.

When the remelting and hardening process on the cam portion 8-1 is completed as described above, the pin 29 moves down based on the command from the control device 46, the base 21 and the LS base 27 are integrated, and the adjacent cam portion 8-2 and repeat the above operation. In this way, all the cam parts 8-1 to 8-8 are sequentially subjected to the remelting and hardening process, and after the process is completed, the torch 20 is moved to the standby position and controlled to be on standby.
After the camshaft 8 that has been subjected to the remelting hardening process is replaced with a new camshaft, the same process as described above is performed on this new camshaft. Repeat this from now on.

(Effects of the Invention) As described above, according to the present invention, a torch that remelts the parts to be treated while only rotating the workpiece, such as a camshaft, which has a plurality of parts to be treated separated in the axial direction, is provided. It can be reciprocated within the axial width of the processing section to form a meandering trajectory, and in particular, the motor of the moving device can be driven in correspondence with the limit switch provided on the switch base and the limit switch provided on the positioning member, and the positioning member Alternatively, since the apparatus also operates a coupling means for selectively coupling the switch base to only one of the torches, it is possible to sequentially re-melt and harden a plurality of parts to be treated.

Furthermore, when the size of the workpiece changes due to a change in model, this can be easily accommodated by changing the LS mounting device.

[Brief explanation of drawings]

Fig. 1 is a front view of the remelting hardening processing device according to the present invention, Fig. 2 is a plan view of the same device, Fig. 3 is a side view of the same device, and Fig. 4 is an enlarged view of the main parts of the reciprocating device. Figure 5 is an enlarged vertical sectional view of the nozzle part of the plasma torch, Figure 6 is a diagram showing the processing locus of the torch on the cam surface of the cam part, and Figure 7 is related to the control system of the remelting hardening processing device. FIG. In the drawing, 1 is a preheating part, 3, 14, 23, 21a
is a motor, 5 and 16 are axial pressing cylinders, 8 is a camshaft, 8-1 to 8-8 are cam parts, 9 is a high-frequency heating coil, 10 is a loader, 11 is a remelting hardening processing part, 18 is a support shaft, 19, 19, 26,
26 is a guide bar, 20 is a plasma torch, 21
is the base of the plasma torch, 21c and 27a are
LS dock, 22 is the feed screw, 25 is the plasma torch holder, 27 is the LS base, 30, 31,
32a... is a limit switch, 33 is a nozzle section, 46 is a control device, and A is a processing locus.

Claims (1)

[Scope of Claims] 1. An apparatus for sequentially remelting and hardening each part of the workpiece while rotating the workpiece, which includes a plurality of workpieces spaced apart in the axial direction, and that comprises: a rotating device that holds and rotates the object to be processed; a torch that remelts each processing portion of the object held by the rotating device; and a torch that sequentially applies the torch to each processing portion of the object to be processed. a moving device that moves the torch and reciprocates within the axial width of the processed portion by forward and reverse rotation of a motor in each processed portion; a switch base which is provided with a pair of limit switches and is movable in parallel along the axial direction of the object to be processed, and a limit switch located along the axial direction of the object to be processed and at a position corresponding to each of the sections to be processed, respectively. A remelting and hardening processing apparatus comprising: a fixed positioning member; and a coupling means for selectively coupling the switch base to either the positioning member or the torch.