JPS62117671A - Resin coating method for metallic parts - Google Patents

Abstract

PURPOSE:To make the film thickness of a coated resin uniform by welding a powdery resin onto the surface of heated metallic parts in a fluidized bed coating tank in which the powdery resin is housed in the fluidized state and injecting a compressed gas to the surface of the metallic parts taken out of the tank. CONSTITUTION:The above-mentioned powdery resin is welded to the surface of the heated metallic parts 10 in the fluidized bed coating tank 24 in which the powdery resin 22 is housed in the fluidized state. The compressed gas is injected by an air injector 42r onto the surface of the metallic parts 10 taken out of the tank 24 to remove the unwelded resin. As a result, the film thickness of the resin coated on the surface of the metallic parts 10 is made uniform. Since the resin powder is not carried away from the fluidized bed tank the working environment is maintained clean.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to an improvement in a method of coating a surface of a metal part with a resin.

Conventional technology A type of method for coating the surface of metal parts with resin is to heat the metal parts to a temperature higher than the melting temperature of the resin by induction heating, etc., and then place the metal in a fluidized immersion tank that contains powdered resin in a fluidized state. Some methods weld the powdered resin onto the surface of metal parts by immersing the parts.

For example, the patent application No. 59-954 filed earlier by the present applicant
18 and Japanese Patent Application No. 60-21427.

Problems to be Solved by the Invention However, according to the conventional resin coating method, resin is welded to the metal parts taken out from the immersion tank, but the welded resin or the surface of the holding jig that holds the metal parts is It was inevitable that unwelded resin powder would adhere to the surface. For this reason, there is an inconvenience that the thickness of the resin coated on the surface of the metal component that has undergone the subsequent reheating process etc. becomes non-uniform. In addition, the resin powder is taken out of the fluidized tank, which impairs the working environment and
When a masking jig is used to hold metal parts in a fluidized bath and locally cover the non-coated surface of the metal parts, the resin powder adhering to the masking jig may stick during the reheating process, etc. This has the disadvantage that its durability is impaired.

Means for Solving the Problems The present invention was made against the background of the following circumstances.
The gist of the method is to apply a resin coating to the surface of a metal part. a resin welding step in which powdered resin is welded; and (2) a gas injection step in which, after the resin welding step, compressed gas is injected onto the surface of the metal parts taken out from the fluidized immersion tank to remove unwelded resin. and include.

By doing this, in the gas injection process, compressed gas is injected onto the surface of the metal parts taken out from the fluidized immersion bath after resin welding, so that the resin powder adhering to the surface of the metal parts is blown away. removed. In addition, when a masking jig is used to hold metal parts in a fluidized bath and locally cover the non-jetting surfaces of the metal parts, the resin powder attached to the surface of the masking jig is also blown away. removed by

Effects of the Invention Therefore, the film thickness of the resin coated on the surface of the metal part that has undergone the subsequent reheating process etc. becomes uniform. In addition, since the resin powder is not taken out of the fluidized tank, the working environment is maintained clean. Second, when a masking jig is used, the resin powder does not stick to the masking jig, which reduces its durability. It has an enhancing effect.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 2 shows a cocoon-shaped rotor 10 for a roots-type supercharger. There is an insertion hole 1 in the center of U-Yu 10.
2 is formed, and one hole 14 is formed in the axial direction in the blade portions on both sides of the blade in order to reduce the weight. The rotor 10 is coated with a resin over the entire outer circumferential surface and the outer circumferential portions of both end surfaces, that is, the portions excluding the periphery of the insertion hole 12 and the hole 14.

A masking jig 66 for preventing the peripheral portions of the insertion holes 12 and holes 14 of the rotor 10 from being coated with resin is constructed as shown in FIG. The first mask member 68 and the second mask member 69 are connected to the rotor 10
The first mask member 68 and the second mask member 69 are placed in close contact around the openings of the insertion hole 12 and the hole 14 to block the upper and lower end surfaces of the rotor 10, respectively. The end surface is large enough to close the insertion hole 12 and the hole 14, and is smaller than the end surface of the rotor 10.

A pair of positioning protrusions 70 are formed on opposing end surfaces of the first and second mask members 68, 69, respectively. The positioning protrusions 70 have a circular cross section with a diameter equal to the diameter of the hole 14 of the rotor 10, and the parts near each other are cut out, and the diameter of the protrusions gradually decreases on the tip side. The first and second mask members 68 and 69 are positioned with respect to the rotor 10 by being fitted into the hole 14 and coming into contact with the opening edge of the hole 14 .

The second mask member 69 includes an elongated hole 72 that opens at the end surface that is brought into close contact with the rotor 10 and whose both ends slightly bite into the positioning protrusion 70, and a bottomed hole 74 that opens at the bottom of the elongated hole 72. is formed. A plate 76 that closes the bottomed hole 74 is fixed to the bottom of the elongated hole 72.
The plate 76 is formed with an elongated elongate 78 whose length in the longitudinal direction is equal to the diameter of the bottomed hole 74 and whose longitudinal direction is the same as the longitudinal direction of the elongated hole 72 .

On the other hand, the first mask member 68 is attached to the hollow engagement shaft 80 so as to be movable relative to the engagement shaft 80 in the axial direction.
An operated portion 82 and a held portion 84 are provided at the upper end of the cylindrical member 86 and disks 88 and 90. The operated portion 82 is fixed by welding disks 88 and 90 to the retaining shaft 80. In addition, the held portion 84
is fixed to the retaining shaft 80 by fitting and welding the upper end of the engaging shaft 80 into a bottomed hole 96 formed in the axial direction. Two positioning holes 98 are formed in the held portion 84 in the radial direction, and an inverted conical recess 102 is formed in the upper surface thereof.

A cylindrical member 1 is attached to the lower portion of the operated portion 82 of the locking shaft 80.
04 is fixed by welding, and a cylindrical portion 108 of a spring retainer 106 is fitted into the cylindrical member 104 so as to be slidable in the axial direction.

A through hole 110 is formed in the engagement shaft 80 and the cylindrical member 104, passing through them in the radial direction.
0 and the spring retainer 106 are connected to this through hole 110.
Both ends of the pin 112 inserted through the pin 112 are supported by the cylindrical portion 108, so that the pin 112 cannot be relatively rotated and can be relatively moved a certain distance in the axial direction. Note that the pin 112 is connected to a ring-shaped cover 1 fitted into the outer peripheral surface of the cylindrical portion 108.
14 prevents it from coming off.

A pair of ears 116 protruding radially from the outer periphery of the cylindrical portion 108 is formed on the cylindrical portion 108, and the lower end of the cylindrical portion 108 is fitted into the first mask member 68. The ear piece 116 is connected to the first mask member 68 by being fixed to the first mask member 68 with a plate-shaped operating member 118 in between.

The first mask member 68 includes a compression coil spring 122 disposed between the ear piece 116 and the disk 90 of the operated section 82.
is always biased downward. That is, the first mask member 68 is allowed to move relative to the retaining shaft 80 in the axial direction within the range in which the pin 112 moves within the through hole 110 .

Further, a bottomed cylindrical fitting member 126 is fitted to the lower end of the engagement shaft 80 and fixed by welding.
A plate-shaped protrusion 130 is formed on the lower side of the fitting member 126. The protrusion 130 has a size that is shorter than the length in the longitudinal direction of the elongate 78 formed on the plate 76 and has a size that allows it to be inserted into the bottomed hole 74.
After insertion into the elongated hole 78, the longitudinal direction of the protrusion 130 extends in a direction perpendicular to the longitudinal direction of the elongated hole 78, so that the protrusion 130 is prevented from coming off from the elongated hole 78. Thereby, the retaining shaft 80 and the second mask member 69 are engaged with each other, and the second mask member 69 and the rotor 10 are prevented from coming apart.

The first and second mask members 68 and 69 are made of a dielectric material such as asbestos and cement (product name: Asbestos Hemint) or ceramics, and are made of tetrafluoroethylene (tetrafluoroethylene). In addition to being coated with ethylene), other parts of the masking jig 66 are also made of materials that are difficult to be heated by induction, such as brass and stainless steel, and are coated with ethylene tetrafluoride as much as possible to coat the resin powder 22. are prevented from fusing.

1 and 3 show a resin coating device 16 for applying a resin coating method to the rotor 10, which includes a resin welding step and a gas injection step, and FIG. 3 is a front view of FIG. 1. It is. Booth 18 constructed by assembling plate member 17 to frame 20
Inside, a fluidized tank 24 is fixed, which can be freely taken in and out from the booth 18, and contains a resin powder 22, which is a powder of a copolymer of 47-fluorinated ethylene and ethylene (trade name: Nearflon). has been done. The resin powder 22 in the fluidized tank 24 is passed through a filter 26 provided at the open bottom of the fluidized tank 24 to an air passage 28 from an air feeder (not shown).
Air is sent into the fluidized tank 24 through the fluidized tank 24 to create a fluidized state.

Note that the filter 26 is preferably a stack of multiple sheets of tracing paper (parchment paper) or a porous plate made of polyethylene or ceramics, which prevents the passage of the resin powder 22 and prevents the passage of air. This allows for

Above the fluidized tank 24, a pair of left and right upper coils 30r,
30j! is fixed on the frame 20 of the booth 18. The upper coils 30r, 3ON are of the same type as coils used for induction hardening, have a larger phase shape than the rotor 10, are arranged to surround the rotor 10 at a predetermined distance from the outside, and further The rotor 10 is connected to electric piping 32 in which electric wires are wired, and is supplied with power from a coil power source (not shown) through the electric piping 32 to preheat the rotor 10 by electromagnetic induction.

Inside the fluidized tank 24, there are a pair of left and right lower coils 36r, 36.
N is embedded in the resin powder 22 on the bottom surface of the coil frame 38 which is fixed to the frame 20 of the booth 18 and hangs down.

These lower coils 36r, 36j! is the above upper coil 30
r, 301, and are connected to the electric piping 40, through which electricity is supplied from the coil power supply, to reheat the rotor 10 by electromagnetic induction. Although not shown, the upper coil 30
r, 3ON and the lower coils 36r, 36β are hollow, and cooling water is flowed through them to maintain their heating efficiency.

Upper coils 30r, 301 and lower coil 36r.

362, air injection devices 42r and 421 are installed on the lower surface of the frame 20 to which the upper coils 30r and 3ON are fixed.
are fixed to each other.In addition, the air injection bag η42r
Since the air injection device 426 and the air injection device 426 have the same configuration, only one air injection device 42r will be explained, and the subsequent explanation will be omitted. One air injection device 42r shown in FIG. 4 is a plane view of the air injection device 42r shown in FIG.
As shown in FIG. 4 (V-V view in FIG. 4), a second member 48 having an annular groove 46 that has approximately the same cross-sectional shape as the first member 44 and the rotor 10 and is larger than the first member 44 and the rotor 10 is attached by a bolt 49. It is constructed by being assembled to the frame 20 of the booth 18, and as a result, an air passage 50 is formed inside.

An insertion hole 52 is formed in the first member 44 and the second member 48, and has approximately the same cross-sectional shape as the rotor 10, is slightly larger than the cross-sectional shape, and is slightly smaller than the annular groove 46. A plurality of injection ports 54 communicating with the air passage 50 are opened at two locations on the inner circumferential surface of each of the air passages 50 . That is, the air injection devices 42r and 426 inject air sent from an air feeder (not shown) through the air passage 50 from the injection port 54.

Above the upper coils 30r, 301, there are a pair of left and right brackets 56r fixed on the plate member 17 of the booth 18,
4 guide rollers 58r each provided in 566
, 58g, and are guided in the vertical direction by being prevented from swinging in the lateral direction.

6ON is provided. Holding members 62r and 62N are attached to the lower ends of the rods 60r and 6ON, respectively. By engaging these holding members 62r and 621 with the masking jig 66, the opening and closing of the booth 18 The rotor 10 equipped with the masking jig 66 carried in through the door 64 is attached to the rods 60r and 60, respectively.
ffi. In addition, the door 64
is designed to be opened only when the rotor 10 is carried in, so the resin coating device 1 is opened during resin coating.
The inside of the housing 6 is sealed off from the outside to be in a sealed state, thereby preventing the resin powder 22 from scattering outside and contaminating the environment.

Since the holding members 62r and 62I2 that engage with the masking jig 66 and hold the rotor 10 have similar configurations,
Only the holding member 62r will be described below. As shown in detail in FIG. 7, the holding member 62r is attached to the rod 60r by assembling a plate 132 to the lower end of the rod 60r with screws.
32, block member 134, thin plate 136 and hook 1
38 is integrated by being screwed together with a screw.

A stepped hole 140 and a hole 142 are formed in block member 134 and hook 138, respectively, for receiving a notch 144 and a spring 146 therein. The spring 146 has its both ends fixed to the inner bottom surface of the notch 144 and the lower surface of the thin plate 136, respectively, and constantly urges the notch 144 downward, so that the held portion 8
4 is inserted into the hook 138, the recess 102
When the head of the notch 144 presses the held part 8
Positioning is performed from above 4. An ear-shaped stopper 148 is formed on the opening side edge of the notch 144, and the stopper 148 is connected to the block member 134.
By contacting the stepped portion between the hook 138 and the hook 138,
Notch 144 is prevented from moving downward any further.

The hook 138 has a U-shaped notch 1 parallel to the carrying direction of the rotor IO, as shown in FIG.
50 is formed, and the rod 80 is inserted into the notch 15.
0 to prevent the rod 80 from swinging laterally. Further, a positioning member 152 is attached to the side wall of the hook 138 in parallel with the notch 150.
By engaging with a positioning hole 98 formed in the held part 84, relative rotation of the rotor 10 connected to the held part 84 is prevented.

Brackets of rods 60r and 601 equipped with holding members 62r and 621 configured as described above) 56r,
On the side opposite to the 56β side, a rack 156r is installed along the axial direction.
, 156Il are provided respectively, and the rack 156
r, 156ffi is the first
They are adapted to mesh with pinions 160r and 160j2, respectively, which are fitted to the support shaft 158 so that they cannot rotate relative to each other and cannot move in the axial direction. A support frame 162 fixed on the booth 18 that supports both ends of the first support shaft 158 rotatably around the axis is connected to a second support frame 162 that is parallel to the first support shaft 158.
Both ends of the support shaft 164 are also rotatably supported, and the first
Support frame 1 of support shaft 158 and second support shaft 164
Sprockets 168 and 16 have a chain 166 wrapped around them via an intermediate member 165 provided on the support frame 162 at one end protruding from the support frame 162.
9 are provided respectively. A pinion 170 is fitted to the second support shaft 164 so as to be non-rotatable and non-movable in the axial direction, and a drive rod 174 is provided with a rack I72 along the axial direction that meshes with the pinion 170, as shown in FIG. A hydraulic cylinder 176 is connected to the lower end and is driven in the vertical direction. At this time, the drive rod 174 is held between a pair of guide rollers 178 to prevent it from rolling and is guided in the vertical direction. Since it is configured as above,
The driving force in the vertical direction of the hydraulic cylinder 176 is generated by moving the drive rod 174 up and down to rotate the second support shaft 164 and transmit the rotation to the first support shaft 158 via the chain 166. 60r, 60j! It is designed to be transmitted to each of the following.

In addition, 180 is a balance device, and the hydraulic cylinder 17
In order to reduce the load applied to the hydraulic cylinder 6, a rod 60r is attached to the tip of the wire of the hydraulic cylinder 176.

A weight (not shown) is lowered to maintain the balance between the 60j2 side and the hydraulic cylinder 176 side.

Upper coil 30r, 3ON and lower coil 36r, 3
61 and the upper coil 30r.

Rotor 1 from inside 301 to inside lower coils 36r, 36e
The moving time of 0 is controlled by a timer (not shown) set in the pattern shown in FIG. 10, and t is the time when the rotor 10 is connected to the upper coil 30r.

3ON, t2 is the time from the end of heating by the upper coils 30r, 301 to the start of heating by the lower coils 36r, 361, t3 is the time when the rotor 10 is the lower coil 3
Lower coil 36r, 36β when in 6r, 366
The power supply time t4 is the upper coil 30r of the rotor 10,
Lower coils 36r, 367 from inside 301! Each shows the travel time inside. Also, the upper coil aor.

Heating temperature control of 30It and lower coils 36r, 36/ is performed by a high frequency heating coil control panel (not shown).

The resin coating method applied in the resin coating device 16 described above will be described below, but of the pair of left and right devices that perform similar operations, only the operation of the right device will be explained, and the rest will be omitted.

First, the door 64 of the booth 18 is opened, and the rotor 10, which has been previously engaged with the masking jig 66, is carried in by an automatic carry-in device (not shown), and the holding member 62r at the tip of the rod 60 is engaged with the masking jig 66. , the door 64 is closed.Next, when the hydraulic cylinder 176 supplied with hydraulic oil from an oil source (not shown) drives the drive rod 174 upward, the driving force is transmitted and the rod 60r is driven downward. As the rotor 10 is rotated, the upper coil 30
inserted into r.

At the same time as the rotor 10 is inserted into the upper coil 30r, the upper coil 30r is supplied with power from the coil power supply for only one second according to the pattern shown in FIG. Ru. At the same time, the rod 60r is further driven downward, and the rotor 10 is moved into the lower coil 36r in the fluidization tank 24, where the resin powder 22 is in a fluidized state. When the rotor 10 stops within the lower coil 36r, the flow of the resin powder 22 stops and the resin powder 22 starts to accumulate around the rotor 10, but at this time, an air pocket is generated under the lower end surface of the rotor 10. In many cases, it may be difficult to weld the resin powder 22 to the lower end surface of the rotor 10, so the rod 6Or is driven further downward according to the pattern shown in FIG.
By pushing down the resin powder 22, defects in welding of the resin powder 22 due to air pockets can be prevented. The time required for the rotor 10 to move up to this point is 14 seconds. After t2 seconds after the end of power supply to the upper coil 30r, power supply to the lower coil 36r is started and continues for t3 seconds.

As a result, the surface temperature of the rotor 10, which decreased during t2 seconds, is raised by -L again, and welding of the resin powder 22 to the surface of the rotor 10 is assisted. In this way, the resin welding step of welding the resin powder 22 to the surface of the rotor 10 heated in the fluidized tank 24 is completed.

Subsequently, as the drive rod 174 is driven downward by the hydraulic cylinder 176, the rod 60r is driven upward and the rotor 10 is taken out from the fluidization tank 24. At this time, the resin powder 22 is brought into a fluidized state again, so that the rotor 10 can be easily removed from the fluidized tank 24. Here, when the rotor 10 passes through the insertion hole 52 of the air injection device 42r, the air sent from the air feeder from the injection port 54 of the air injection device 42r is injected toward the rotor 10. The unwelded resin powder 22 adhering to the surface and the surfaces of the masking jig 66 and the like is blown off and removed. After the gas injection process is completed in this manner, the rotor lO is carried out through the door 64, and a new rotor is carried in, and the resin welding process and the gas injection process are performed again. Note that the above resin welding process and gas injection process are performed in the same manner in the left device.

As described above, according to this embodiment, when coating the surface of the rotor 10 with the resin powder 22, the unwelded resin powder 22 adhering to the surfaces of the rotor 10, the masking jig 66, etc. is removed. After the subsequent reheating process, the thickness of the resin coated on the surface of the rotor 10 becomes uniform, and since the resin powder 22 is not taken out of the fluidization tank 24, the working environment is maintained clean, and the masking process is easy. This results in the effect that the durability of the tool 66 is improved.

The above-mentioned embodiment is merely one embodiment of the present invention, and various modifications may be made to the present invention without departing from the spirit thereof.

[Brief explanation of drawings]

FIG. 1 is a side view showing the inside of a resin coating apparatus to which the present invention is applied. FIG. 2 is a perspective view showing a cocoon-shaped rotor for a roots-type supercharger coated with resin in the apparatus of FIG. FIG. 3 is a front view of FIG. 1. FIG. 4 is a plan view of the air blower shown in FIG. 1. FIG. 5 is a sectional view of FIG. 4 taken along line V-V. FIG. 6 is a sectional view of the masking jig attached to the rotor of FIG. 2, viewed from the side. FIG. 7 is a sectional view of a main part of the holding member that engages with the masking jig shown in FIG. 6, viewed from the side. FIG. 8 is a diagram of FIG. 7 viewed from ■- to 1yA. FIG. 9 is a plan view showing a part of the resin coating apparatus shown in FIGS. 1 and 3. FIG. FIG. 10 is a diagram showing the heating and movement pattern of the rotor in the resin welding process. 10: Rotor (metal parts) 22: Resin powder (powdered resin) 24: Fluidized tank (fluidized immersion tank) Applicant Toyota Motor Corporation Figure 1 @ Figure 2 Figure 3 Figure 6 + -4--- 134 7th rIA Figure 8

Claims (1)

[Claims] A method for coating the surface of a metal part with a resin, the method comprising applying the powdered resin to the heated surface of the metal part in a fluidized immersion bath containing the powdered resin in a fluidized state. a resin welding step of welding the resin; and a gas injection step of injecting compressed gas onto the surface of the metal parts taken out from the fluidized immersion tank to remove unwelded resin after the resin welding step. A resin coating method for metal parts.