JPH0810958A - Cladding by welding equipment - Google Patents

Abstract

PURPOSE:To improve production efficiency by automating cleaning of holding surface of a rotating table to place a work in build up welding the metal powder for welding with plasma arc. CONSTITUTION:The equipment is provided with a rotating table 38 which holds a work A and welding torch 25 facing each other and rotates the work A around its center line, a transporting means 60 to clamp the work at a waiting position and transport it to the rotating table 38 and a rotating table cleaning means 80 to clean the holding surface 38a of rotating table 38 to hold the work A. Further the rotating table cleaning means 80 is provided with a moving part 82 free to move in the direction of the holding surface 38a of rotating table and the tip part thereof a grinder 84 free to rotate around its center line and a grinder drive source 84. In cleaning the holding surface 38a, the moving part 82 is moved in the holding surface 38a direction, the grinder 84 is pressed to the holding surface 38a and rotated and then deposited parting agent and oxide film are ground/removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a build-up welding apparatus for melting a metal powder material for welding by a plasma arc and build-up welding it on the surface of a workpiece, and more particularly to a supply valve or an exhaust gas of an internal combustion engine. The present invention relates to a overlay welding apparatus suitable for overlay welding welding metal on a valve head of a valve.

[0002]

2. Description of the Related Art Conventionally, a valve head of a valve (workpiece) of an intake valve or an exhaust valve of an internal combustion engine is repeatedly brought into contact with a valve seat at high speed, so that the valve head has high wear resistance. Is required. Therefore, as shown in FIG. 5, for example, Co- is formed on the outer edge portion of the valve head 2 of the valve 1 (hereinafter, referred to as a material valve) to be overlay welded.
A welding material 3 having a high wear resistance, such as a Cr-WC alloy, is overlay welded, and then the overlay weld portion 3 is subjected to mechanical processing such as grinding to obtain a desired shape.

To perform overlay welding on the valve head 2, the lower end 1a of the material valve 1 is placed on the holding surface of the rotary table, and the welding torch is opposed to the outer edge of the valve head 2 of the material valve 1. While rotating the rotary table at a predetermined rotation speed, the overlay welding is performed under the same conditions from the starting point of the overlay welding to a position where it makes one revolution, that is, 360 °.

[0004]

By the way, in the conventional overlay welding, a release agent composed of an oil and fat component adhered to the lower end portion 1a of the material valve 1 during forging is transferred to the holding surface of the rotary table and held therein. In many cases, the surface is stained, and the transferred release agent is seized with the spatter generated during welding and seizes on the holding surface to form a strong oxide film. Therefore, there is a problem in that the oxide film becomes an obstacle, which hinders the work of attaching and detaching the material valve 1 to and from the rotary table.

As a means for solving this problem, it has been considered to arrange a water cooling pipe inside the rotary table and cool the holding surface of the rotary table to prevent the formation of the oxide film. The release agent attached to the holding surface serves as a heat insulating layer to prevent heat radiation from the holding surface, so that the cooling efficiency is lowered and the formation of an oxide film cannot be prevented. Therefore, conventionally, the release agent and the oxide film adhering to the material valve 1 are manually removed before the overlay welding of the material valve 1, but this removal operation requires a lot of time. In addition, the production efficiency of the product valve is reduced, and it becomes difficult to reduce the cost of the product valve.

The present invention has been made in view of the above circumstances, and automatically removes the mold release agent and the oxide film adhering to the holding surface of the rotary table on which the workpiece is to be placed, and the product valve It is an object of the present invention to provide a build-up welding apparatus capable of improving the production efficiency of

[0007]

In order to solve the above problems, the present invention employs the following overlay welding equipment. That is, the overlay welding device according to claim 1 is a device for melting a metal powder for welding by a plasma arc to perform overlay welding on the surface of a workpiece, and the overlay welding on the surface of the workpiece. A welding torch for carrying out the work, a rotary base for holding the workpiece against the welding torch, and rotating the workpiece about its axis, and a workpiece for holding the workpiece in a standby position for rotation. And a rotary table cleaning means for cleaning a holding surface of the rotary table for holding the workpiece, which is provided in the vicinity of the rotary table. A moving part that is movable in the direction of the holding surface of the rotary table, a grinder that is provided at the tip of the moving part and that is rotatable around an axis, and a drive source that rotates the grinder. Is characterized by.

According to a second aspect of the overlay welding apparatus of the present invention, in the overlay welding apparatus of the first aspect, the grinder is a turntable rotatable about an axis, and the turntable is detachable from the turntable. And a pad impregnated with an abrasive.

Further, a build-up welding apparatus according to a third aspect is the build-up welding apparatus according to the second aspect, wherein the abrasive is a powder whose main component is any one of diamond, corundum, and silicon carbide. It is characterized in that the pad is made of either an elastic body or an elastic cloth.

Further, a build-up welding apparatus according to a fourth aspect is the build-up welding apparatus according to the first aspect, characterized in that the drive source is provided with control means for controlling the rotational speed of the grinder. .

[0011]

In the overlay welding apparatus according to claim 1 of the present invention, by moving the moving portion toward the holding surface of the rotary table, the grinding machine provided at the tip of the moving portion moves the holding surface. The release agent and the oxide film adhered to the holding surface are automatically ground by rotating the grinding machine around the uniaxial line by the drive source, and the grinding surface is quickly removed from the holding surface. Then, the holding surface is cleaned. As a result, there is no risk of hindrance in positioning or the like when the work piece is placed on the holding surface, and the production efficiency of the product valve is improved.

Further, in the overlay welding device according to claim 2,
When the pad impregnated with the abrasive is attached to and removed from the rotary disk, the grinding efficiency is recovered only by removing the pad when the pad is worn and the grinding efficiency is lowered. There is no need to replace the, and work efficiency improves.

Further, in the overlay welding device according to claim 3,
By using the abrasive as a powder whose main component is any one of diamond, corundum, and silicon carbide,
These powders quickly grind and remove the release agent and oxide film adhered to the holding surface. In addition, since the pad is made of an elastic body or a cloth having elasticity, the pad is brought into close contact with the holding surface, and the release agent and the oxide film attached are quickly removed.

Further, in the overlay welding device according to claim 4,
The number of revolutions of the grinder is controlled by the control means so that the holding surface has the best grinding state, and grinding is performed in accordance with the surface state of the holding surface to bring the holding surface into the best clean state.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A build-up welding apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a build-up welding apparatus equipped with the welding torch of this embodiment, and FIG. 2 is a plan view of the build-up welding device. Welding means 20 for overlay welding on the valve head of the material valve A, and the welding means 2
With the material valve holding means 30 for holding the material valve A in a state of being inclined at a predetermined angle so that the valve head of the material valve A faces the welding torch 25 of 0 and rotating the material valve A about its axis, and the welding means 20. The product valve stock means 50 for storing the product valve B subjected to the overlay welding and the material valve A from the material valve stock means 10 to the material valve holding means 30 and the product valve B as the material valve. Valve conveying means (workpiece conveying means) 60 for conveying from the holding means 30 to the product valve stock means 50, and the welding means 2
No. 0 position of the welding torch 25, welding conditions such as plasma gas conditions, powder supply conditions, operation conditions for commanding a control system for controlling the rotation conditions of the material valve A, and the material valve holding means 30. Rotating table cleaning means 8 provided in the vicinity
It has 0 and.

The welding means 20 is provided with a guide column 21 standing upright in the vertical direction, a movable table 22 movably attached to the guide column 21 in the vertical direction, and a horizontal movement on the movable table 22. A movable table 23 that can be attached,
A bracket 24 fixed to the lower end of the moving table 23,
The bracket 24 is provided with a welding torch 25 attached to the tip end in the vertical direction, and a hopper 26 for supplying the welding torch 25 with a welding material powdered by an argon gas flow.

The material valve holding means 30 is provided with a rotary table (rotary table) 31 against which the end surface of the material valve A on the valve head 2 side abuts, and a material valve A which is provided diagonally above the rotary table 31. The valve stem of the material valve A by pressing the valve stem from above from the rotary table 31.
Is provided with a valve attaching / detaching means 32 for removably holding and a valve attachment positioning means 33 for locating and attaching the material valve A substantially coaxially with the rotary shaft of the rotary table 31.

The valve attachment positioning means 33 includes a support member 34 for obliquely supporting the material valve A, an axial movement means 35 for moving the support member 34 in the axial direction of the material valve A, and the support member 34. A radial direction moving means 36 for moving the material valve A in the radial direction is provided.

The rotary table 31 includes the guide columns 2
1, a swing block 37 rotatably held by a support portion 37a, a rotary table 38 rotatably attached to the swing block 37, and a swing block 37 fixed to the swing block 37.
The rotary shaft includes a motor 39 connected to the rotary table 38 via a belt.

The valve conveying means 60 is directed from the material valve stock means 10 to the material valve holding means 30 and further from the material valve holding means 30 to the product valve stock means 50 about a fixed point 62.
Further, from the product valve stock means 50 toward the material valve stock means 10, a swing arm 63 is swingably attached, and a rotary member 64 is attached to the tip end side of the swing arm 63 so as to be rotatable. It is equipped with two chuck means 65, 66 which are attached to the outer peripheral portion of the rotary member 64 at two positions sandwiching the rotary shaft of the rotary member 64 and which clamp the valve stem of the material valve A or the product valve B from the side surface. There is.

Reference numeral 71 in FIG. 2 is a cooling water circulating means for circulating cooling water to the welding means 20 and the material valve holding means 30, 72 is a welding power supply device for supplying power to the welding means 20, and 73 is a welding means 20. It is a comprehensive control means for controlling the position of the welding torch 25, welding conditions such as plasma gas conditions, powder supply conditions by the powder supply means 26, and rotation conditions of the material valve A by the material valve holding means 30.

As shown in FIG. 3, the rotary table cleaning means 80 includes a swing block 3 to which the rotary table 38 is attached.
7, a pedestal 81 provided at one end, and an arm that is slidably supported on the pedestal 81 in the direction of the holding surface 38a of the rotary table 38 at a predetermined inclination angle and can be fixed at a predetermined position in the sliding direction ( Moving part) 82, a speed reducer (control means) 83 horizontally provided above the tip of the arm 82, and a uniaxial line perpendicular to the tip provided at the tip of the speed reducer 83. And a drive unit (drive source) 85 which is built into the pedestal 81 and rotates the grinder 84 via a speed reducer 83. In the rotary table cleaning means 80, the grinder 84 is in a state where the arm 82 is slid for a predetermined distance in the direction away from the holding surface 38a.
Is located above the holding surface 38a, and when the arm 82 is slid by a predetermined distance toward the holding surface 38a, the peripheral edge of the grinder 84 is held at the center of the holding surface 38a. It is configured to be in close contact with the surface 38a.

As shown in FIG. 4, the grinding machine 84 is a disk-shaped rotary disk 88 that is fixed to the tip of a shaft 86 and has a velcro tape 87 adhered to the surface thereof, and is removable from the rotary disk 88. And a disk-shaped pad 90 impregnated with a dry abrasive in the inside thereof. As the abrasive, a powder containing a material having a high hardness such as diamond, corundum, or silicon carbide as a main component is preferably used. Further, as the pad 90, either hard rubber (elastic body) or elastic cloth such as rusher cloth is preferably used.

Next, a method of overlay welding the welding material 3 on the outer edge portion of the valve head 2 of the material valve 1 using the overlay welding apparatus of this embodiment will be described. First, the shape and material of the material valve 1 to be overlay welded, the welding material 3 to be overlayed on the valve, etc. are input from the operation panel 70. As a result, the optimum operation program for the valve to be overlay welded is selected from the plurality of operation programs set for each valve. According to this operation program, for example, the operation of the valve conveying means 60 (for example, the gripping position by the chucking means 65, 66, the supply position to the material valve holding means 30, the discharge position to the product stocking means 50, the waiting time between each operation) , Sampling timing, number of samples, etc.), welding conditions such as the position of the welding torch 25 of the welding means 20 and plasma gas conditions, powder supply conditions by the powder supply means 26, rotation of the material valve A by the material valve holding means 30. Conditions etc. are set. The arm 82 of the turntable cleaning means 80 is slid for a predetermined distance in the direction away from the holding surface 38a, and the grinder 84 is retracted above the holding surface 38a.

After that, a series of operations as described below are automatically performed by the selected operation program. First, the swing arm means 63 is replaced with the material valve stock means 10.
The valve stem of the supplied material valve A is swung toward the side, and is clamped and held from the side surface by the chuck means 65. Next, the swing arm means 63 is swung by swinging to the material valve holding device 30 side, and the material valve A gripped by the chuck means 65 sandwiches the rotary shaft of the rotating member 64 with respect to the material valve holding means 30. Position

Next, the rotary member 64 is rotated 180 ° to position the material valve A sandwiched by the chuck means 65 above the holding surface 38a of the rotary table 38 of the material valve holding means 30. Next, the axial movement means 35 is moved in the axial direction of the material valve A to move the tip end portion of the support member 34 to a predetermined position, and then the radial movement means 36 is brought close to the material valve A in the radial direction. The tip of the support member 34 is brought into contact with the outer surface of the valve stem of the material valve A. After that, the gripping by the chuck means 65 is released, and the swing arm means 63 is moved so as to be slightly separated from the material valve A, whereby the holding of the material valve A by the chuck means 65 is released, and the supporting member is The material valve A is held in an inclined state by 34. After that, the radial direction moving means 36 is further moved in the radial direction of the material valve A, and the material valve A is moved in the radial direction of the rotary table 38 by the support member 34, so that the axial center of the material valve A and the rotary table 38 are moved. Make it coaxial with the axis of rotation. The movement amount of the radial direction moving means 36 is also preset by the operation program.

Next, the motor 39 is rotated to rotate the turntable 38.
Is rotated at a predetermined rotation speed to move the moving bases 22 and 23 so that the plasma arc of the welding torch 25 is brought into contact with the outer edge portion of the valve head 2, and the carrier gas is introduced into the plasma arc from the powder injection hole 16 into the plasma arc. The supplied metal powder is jetted and melted, and the molten metal is welded to the outer edge of the valve head 2 by overlay welding.

On the other hand, while the overlay welding is being performed by the welding torch 25, the material valve A for the overlay welding is conveyed from the material valve stock means 10 to the vicinity of the material valve holding means 30.

Next, when the overlay welding is completed, the motor 39
To stop the rotation of the turntable 38. Then, the product valve B in which the swing arm 63 is overlay welded
The chuck means 66 not holding the material valve A is moved toward the product valve B so that the product valve B is held by the chuck means 66 and removed from the rotary table 38.

Next, the motor 39 is rotated to rotate the turntable 38.
By rotating the pad 82 of the grinder 84 provided on the speed reducer 83 around a vertical axis while sliding the arm 82 toward the holding surface 38a of the rotary table 38. , The pad 9 mounted on the grinder 84
The pad 90 is brought into close contact with the holding surface 38a of the rotary table 38 so that the peripheral portion of 0 is located at the center of the holding surface 38a.
In this way, the arm 82 is attached to the holding surface 38a of the turntable 38.
The pad 90 is brought into close contact with a predetermined position of the holding surface 38a by one operation of sliding the pad 90 toward.

When the rotary table 38 is rotated for a predetermined time, the abrasives such as diamond, corundum, and silicon carbide impregnated in the pad 90 quickly remove the release agent and oxide film adhered on the holding surface 38a. Grinding the holding surface 38a
Clean up. By this step, the release agent and the oxide film adhering to the holding surface 38a of the rotary table 38 are removed, so that there is no possibility that the positioning or the like when the material valve A is placed on the holding surface 38a will be hindered. Product valve production efficiency is improved.

When the pad 90 is attached to the rotary disk 88, it is only necessary to attach the magic tapes 87 and 89 to each other. Therefore, even if the pad 90 is worn and the grinding efficiency is lowered, the pad 90 can be easily attached. Grinding efficiency is restored by attaching and detaching. Further, it is not necessary to replace the entire grinding machine 84, and the working efficiency is improved.

After the cleaning of the holding surface 38a of the rotary table 38 is completed, the arm 82 is slid again for a predetermined distance in the direction away from the holding surface 38a, and the grinder 84 is retracted to the outside of the holding surface 38a. The swing arm 63 is swung to move to the material valve supply mechanism 10, the material valve A is clamped by the chuck mechanism 65, and then the material valve A is directed to the material valve holding mechanism 30 in the same manner as the above-described procedure. Transport. After that, by repeating the above-mentioned operation again, overlay welding can be continuously performed on the valve head 2 of the material valve A.

As described above, according to the overlay welding apparatus of this embodiment, the rotary table cleaning means 80 for cleaning the holding surface 38a of the rotary table 38 is provided in the vicinity of the rotary table 38, and the rotary table 38 is provided. The cleaning means 80 includes an arm 82 slidably supported by a pedestal 81, a speed reducer 83 provided at the tip of the arm 82, and a vertical uniaxial line provided at the tip of the speed reducer 83. A grinder 84 that can rotate freely, and a drive unit 85
Since the grinding machine 84 can automatically grind the release agent and the oxide film adhered to the holding surface 38a by the grinding machine 84 and quickly remove them from the holding surface 38a. The cleaning of can be promptly performed. Therefore, there is no possibility that positioning or the like will occur when the material valve A is placed on the holding surface 38a,
The production efficiency of product valves can be improved. Further, the pad 90 can be brought into close contact with the holding surface 38a by only one operation of sliding the arm 82 toward the holding surface 38a of the rotary table 38.

Since the pad 90 impregnated with the abrasive is attached to and removed from the rotary disk 88, the pad 90
Even if the grinding efficiency is reduced due to wear, the grinding efficiency can be promptly recovered only by removing the pad 90, and it is not necessary to replace the entire grinding machine 84.
Work efficiency can be improved.

Further, since the speed of rotation of the turntable 88 is controlled by the speed reducer 83, grinding can be performed in accordance with the surface condition of the holding surface 38a, and the holding surface 38a should be in the best clean state. You can

[0037]

As described above, according to the first aspect of the present invention.
According to the build-up welding apparatus described above, the rotary table cleaning means is provided for cleaning the holding surface of the rotary table for holding the workpiece, and the rotary table cleaning means is movable in the direction of the holding surface of the rotary table. Part, a grinder that is provided at the tip of the moving part and is rotatable about an axis, and a drive source that rotates the grinder, so that the mold release attached to the holding surface by the grinder The agent and the oxide film can be automatically ground and quickly removed from the holding surface, and the holding surface can be cleaned. Therefore, there is no possibility that positioning or the like will occur when the workpiece is placed on the holding surface, and the production efficiency of the product valve can be improved. Further, the grinding machine can be brought into close contact with the holding surface by only one operation of sliding the moving portion toward the holding surface.

Further, according to the overlay welding device of the second aspect, the grinding machine is a rotary disk which is rotatable about an axis, and the rotary disk is detachably mounted and impregnated with an abrasive. Since the pad is constituted by the pad, even when the pad is worn and the grinding efficiency is lowered, the grinding efficiency can be recovered only by detaching the pad.
It is not necessary to replace the whole and work efficiency can be improved.

Further, according to the overlay welding device of the third aspect, since the abrasive is a powder containing at least one of diamond, corundum, and silicon carbide as a main component, it adheres to the holding surface. The release agent and oxide film thus formed can be quickly ground and removed. Further, since the pad is made of either an elastic body or a cloth having elasticity, the pad can be brought into close contact with the holding surface, and the release agent and the oxide film attached can be promptly removed.

Further, according to the overlay welding device of the fourth aspect, since the drive source is provided with the control means for controlling the rotation speed of the grinding machine, the rotation speed of the grinding machine is controlled. Grinding can be performed according to the surface state of the holding surface, and the holding surface can be in the best clean state.

[Brief description of drawings]

FIG. 1 is a front view showing a build-up welding apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing a build-up welding apparatus according to an embodiment of the present invention.

FIG. 3 is a plan view showing a rotary table cleaning means of the overlay welding apparatus according to the embodiment of the present invention.

FIG. 4 is a side view showing a grinding machine according to an embodiment of the present invention.

FIG. 5 is a partially cutaway side view showing a valve on which overlay welding is performed.

[Explanation of symbols]

 25 Welding torch 30 Material valve holding means 38 Rotating table 38a Holding surface 60 Valve conveying means 80 Rotary table cleaning means 82 Arm (moving part) 83 Speed reducer (control means) 84 Grinder 85 Drive part (drive source) 86 Shaft 87, 89 Velcro 88 Rotating disc 90 Pad

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Minoru Nakane 1230 Kamijideya, Okegawa City, Saitama Prefecture Mitsubishi Materiali Co., Ltd. Okegawa Works

Claims (4)

[Claims] 1. A device for melting a metal powder for welding by a plasma arc to perform overlay welding on a surface of a workpiece, a welding torch for overlay welding on the surface of the workpiece, and the welding torch. A rotary table that holds the workpiece against the welding torch and rotates the workpiece around its axis, and a workpiece that grips the workpiece at the standby position and transfers it to the rotary table. And a rotary table cleaning means provided near the rotary table for cleaning a holding surface of the rotary table for holding the workpiece. The rotary table cleaning means is provided in the direction of the holding surface of the rotary table. The overlay welding apparatus comprising: a movable part that is movable to the inner side; a grinder that is provided at the tip of the movable part and that is rotatable around an axis; and a drive source that rotates the grinder. . 2. The grinding machine is composed of a rotary disk that is rotatable about an axis and a pad that is detachably attached to the rotary disk and is impregnated with an abrasive. The overlay welding device according to 1. 3. The abrasive material is made of powder containing at least one of diamond, corundum, and silicon carbide as a main component, and the pad is either an elastic body or an elastic cloth. The overlay welding apparatus according to claim 2. 4. The overlay welding apparatus according to claim 1, wherein the drive source is provided with control means for controlling the rotation speed of the grinding machine.