JPH01207166A - Method and device for coating to cylindrical object - Google Patents

Abstract

PURPOSE:To obtain excellent coated film characteristics by supporting a cylindrical object and a transfer roller for coating in parallel and relatively attachably and detachably and bringing a coating material sticking to the transfer roller into contact with the outside peripheral face of the cylindrical object. CONSTITUTION:The cylindrical object W and the transfer roller 10 are supported in parallel in such a manner that said object and roller can be attached to and detached from each other. The coating material sticks at a uniform thickness on the surface of the transfer roller 10 when a coating material container 14 moves upward toward the transfer roller 10 and said roller is immersed in the coating material in the coating material container 14. The coating material sticking on the transfer roller 10 is brought into contact with the outside peripheral face of the cylindrical object W and is rotated in the same direction by approaching the cylindrical object W and the transfer roller 10 each other thereafter. The coating material sticking on the transfer roller 10 is transferred onto the outside peripheral face of the cylindrical object W by this rotation. The film thickness is thereby uniformized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coating method that can be applied to the outer surface of a cylindrical object such as a piston of an internal combustion engine to efficiently obtain excellent coating film properties. It is something.

[Problems to be solved by conventional techniques and inventions] Conventionally,
When forming a thin coating film on part or all of the outer surface of parts such as pistons, a method using a coating spray is used. However, with this method, 40 to 6
The yield rate of the paint used is about 0%, and since it is a spray type, a painting booth is required and the equipment is complicated. Oversprayed paint particles worsen the working environment. Since the formed coating film itself consists of a collection of paint particles, the surface of the coating film is not sufficiently smooth, and if only the convex surfaces of the part are painted, it is necessary to mask the other concave surfaces. Conventional coating methods have had various problems, such as a reduction in productivity.

In view of these circumstances, it is an object of the present invention to provide a coating method and apparatus, particularly for cylindrical objects, that are efficient and provide excellent coating film properties.

[Means and effects for solving the problems] In the method of the present invention, as shown in FIG. The paint container 14, which is supported so as to be able to move (see arrows A and A') and is disposed below the transfer roller IO, moves upward toward the transfer roller IO (arrow B), and the transfer roller 10 is immersed in the paint in the paint container 14, so that the paint adheres to its surface with a uniform thickness, and then by bringing the cylindrical object W and the transfer roller lO closer together (arrow A), the transfer is completed. The paint adhered to the roller 10 is brought into contact with the outer peripheral surface of the cylindrical object W, and the transfer roller 10 and the cylindrical object W are rotated in the same direction as shown by the arrows. Due to this rotation, the paint adhering to the transfer roller 10 is transferred to the outer circumferential surface of the cylindrical object W, but since the transfer roller 10 and the cylindrical object W are held parallel to each other, the paint adhered to the transfer roller 10 is constant and constant with respect to the cylindrical object W. Uniform paint transfer occurs. Note that the transfer roller 10 and the cylindrical object W
The same applies when the paint container 14 is placed below the transfer roller 10 with the paint container 14 set horizontally.

〔Example〕

Hereinafter, one embodiment of the method and apparatus of the present invention will be described with reference to FIG. 1 based on FIGS. 2 to 5.

First, FIGS. 2 to 5 show an example of the configuration of an apparatus for carrying out the method of the present invention. In the figures, 1 is a frame made of shaped steel etc. (see FIG. 4) A guide base 4 is fixed to a pedestal 3 on the body 1 and is indicated by an arrow A in FIGS. 3 and 4.
, A'' (arrow A shown in Figure 1)
A) A supporting member attached to the guide base 2, 5 a driving means fixed to the guide base 2 and for reciprocating the supporting member 4, 6 a supporting member 4
8 is a drive means consisting of an air actuator or the like that rotates the rotating shaft 6 via a bevel gear 9.9'; The transfer roller has a hollow cylindrical shape, is attached coaxially to the rotating shaft 6, and has an inclined surface 10a formed on the inside at its upper end edge, as shown in FIG. Here, as shown in FIGS. 7 and 8, the transfer roller 1O may have an inclined surface tab on the outside of its upper edge, or inclined surfaces 10'a and io'b on both the inner and outer sides. Good, 11 is a bracket fixed to the support member 4 with a bolt or the like through an elongated hole 12, and 13.13' can be rotated parallel to the rotation axis 6 by arms 11a and ll'a of the bracket 11. A pair of positioning rollers 14 are pivotally supported by the transfer roller 10 and are disposed at predetermined positions on both sides of the transfer roller lO and in front of the transfer roller IO along the arrow A direction. With reference to FIG. A bracket 15a is intermittently fed by a driving means (not shown) on a guide rail l'a laid along a
and the transfer roller lO are parallel to each other.
5a, and a pad 15C connected to the rotation shaft 15b via a universal hinge 15d and capable of gripping the upper end of the cylindrical object W. This is a carrying unit that can bring a shaped object W to a predetermined position (hereinafter referred to as a stop position) in front of the transfer roller 10 along the direction of arrow A as shown in FIGS. 2 and 3. This carrying unit 15 is arranged so that the coating area W of the cylindrical object W is connected to the transfer roller 10 at the stop position.
Further, the height at which the non-painting area Wb defined by the upper outer circumferential surface should be mounted on the frame 1a is set so that it can correspond to the positioning a-ra 13, respectively.

A bevel gear 16a fixed to the frame body 1b at an upper position corresponding to the driving means 8 on the frame body 1 and capable of rotating and reciprocating movement is attached to the carrier unit 15 positioned at the stop position. a driving means that rotates the cylindrical object W by meshing with and rotating the bevel gear 15a;
Reference numeral 17 denotes a slide base in which the receiver reciprocates on the table 18 (arrows A+, A'+) by built-in driving means along the same direction as the reciprocating direction of the support member 4, and 19 denotes the slide base. The frame 1c supports the stand 18 so as to be slidable in the direction (arrow C, C') perpendicular to the direction of reciprocating movement of the frame 17.
The base block 20, 20' fixed to the slide base 17 consists of a pair of row arms rotatably and vertically supported by a holding member 21 fixed to the slide base 17, and the supporting unit is positioned at the stop position. The non-painted area W of the cylindrical object W, which is carried by the cylindrical object W, is positioned by the roller 13°1.
The pressure roller is arranged so that it can be repositioned at approximately the center position between 3' and 3'. In addition, the above-mentioned frame 1. la, l
b and lc are each fixedly installed on the pedestal of the device.

Next, a description will be given of the coating process of the cylindrical object W using the apparatus configured as described above.The carrying unit 15 holding the cylindrical object W
When the cylinder W is brought to the stop position, the cylinder W is placed between the positioning rollers 13, 13' and the pressure rollers 20, 20', as shown in FIGS. 2 and 3. At this time, the support member 4 moves in the A' direction and is located at the starting point of the outward path of the reciprocating movement (hereinafter simply referred to as the starting point), and the slide base 17 moves in the A'+ direction and locates at the starting point of the outward path of the reciprocating movement. point (hereinafter referred to as the starting point), so that when the cylindrical object W intervenes between the positioning roller 13, 13' and the pressing rollers 20, 20', there is a sufficient distance to avoid collision between the two. is set. In this state, when the paint container 14 waiting below the transfer roller 10 is raised by a lifting means (not shown) (
1 and 3, arrow B), the transfer roller lO is immersed into the paint in the paint container 14, and then the paint container 1
4 descends, thereby forming a paint film on the outer surface of the transfer roller 1O. By the way, the paint used is, for example, molybdenum disulfide dissolved in an organic solvent, and the paint container! The amount and viscosity to be filled into the transfer roller l are adjusted to predetermined set values.
The thickness of the coating film formed on the cylindrical object W is as described below.
This significantly affects the quality of the transfer when transferring paint to. That is, the uniformity of the thickness of the coating film on the transfer roller IO is important, and for example, in the case of the transfer roller 10G illustrated in FIGS. 9 and 1O, problems arise regarding such uniformity. The paint P adhering to the upper end surface 100a of the transfer roller 10G drips onto the outer circumferential surface of the transfer roller 100, causing local unevenness of the paint film, which makes it difficult to make the thickness of the paint film P0 uniform. It disappears. On the other hand, since the transfer roller 1O is formed with the inclined surface 10a (see FIG. 6), the paint does not adhere to the upper end surface of the transfer roller 10, and the paint attached to the inclined surface 10a is removed from the transfer roller 10. There is no dripping onto the outer circumferential surface of the lO, and therefore a coating film P having a uniform thickness is formed. Furthermore, in the case of the inclined surface lOb shown in FIG. 7, the paint P adhering to the inclined surface 10b due to immersion in the paint container 14 flows down evenly over the entire upper outer circumferential surface of the transfer roller lO, so that there is no unevenness in the coating lap. This does not occur, and the film thickness on the upper outer circumferential surface does not become thinner than the film thickness on the lower outer circumferential surface, that is, the thickness of the coating is uniform over the entire outer circumferential surface of the transfer roller 10.

Also, in the case of the example shown in FIG. 8, the inclined surface 10'a.

10'b, it is possible to achieve uniformity of *HP@ as described above, but in both cases, the inclined surface 10a.

The dimensions and inclination angle of 10'a, 1Ob, 1G'b, etc. can be appropriately set according to the viscosity of the paint, etc.

The transfer roller 10 on which the coating film P0 has been formed approaches the cylindrical object W as the support member 4 moves forward from the starting point, and when the support member 4 reaches the end point of the forward movement, the positioning roller 1
3 and 13', it is located in the immediate vicinity of the cylindrical object W.

On the other hand, the positioning rollers 13, 13' and the pressing rollers 20, 20' on the opposite side to the cylindrical object W begin to approach the cylindrical object W as the slide base 17 moves forward from the starting point. At this time, the cylindrical object W is not necessarily positioned at the center between the rollers 13.13' and 20.20', that is, it may be eccentric with respect to the transfer roller 10. FIG. 11 shows an example of such an eccentric state.
When the amount of eccentricity with respect to the axis 01 of
comes into contact with. In this case, the slide base 17 slides on the base block 19 in the C direction via the support plate 18 (see FIG. 2), thereby causing both pressure rollers 20 and 20' to form a cylindrical shape as shown in FIG. It comes into contact with the outer peripheral surface of the object W. Further forward movement of the slide base 17 causes the cylindrical object W to be pushed toward the transfer roller 10 by the pressure rollers 20 and 20', and then the positioning roller 13' comes into contact with the cylindrical object W (see FIG. 13). ), in this case, contrary to the above, the slide base 17 slides in the C' force direction as the cylindrical object W is guided by the positioning roller 13', so that the eccentricity δ of the cylindrical object W becomes zero. Then, the cylindrical object W is moved to a position as shown in FIG.
La13. 13', 2o, 20' Press evenly. In this aligned state, the parallelism between the cylindrical object W and the transfer roller 10 is maintained with high precision, and at this time, the coating film P0 of the transfer roller 1° is parallel to the cylindrical object W.
In this way, the cylindrical object W contacts the outer surface of the coating area W of the positioning roller 13 (hereinafter referred to as a contact state).
13' and the pressing rollers 20, 20', each roller 13 at the stop position of the carrying unit 15
．． Even if accurate positioning of the cylindrical object W (7) with respect to 13', 20.
' etc., the cylindrical object W is automatically aligned, and thereby accurate positioning of the cylindrical object W and the transfer roller 10, particularly adjustment of parallelism, can be quickly performed. Further, the transfer roller 10 is set relative to the positioning roller 13, 13'' so that a gap approximately equal to the thickness of the coating film P0 can be defined between the transfer roller 10 and the outer surface of the cylindrical object W in the contact state. Although the positional relationship is set, the gap can be adjusted as appropriate according to the change in the diameter of the cylindrical object W.
As shown in Figure 5, the diameter of the cylindrical object W is at two points t1wA.
As shown in
2, the positioning rollers 13, 13' are moved toward the transfer roller 10 (see the two-dot chain line) by shifting the position of the bracket 11. The gap can be set to an optimal size.

Next, while the transfer roller 10 remains in contact, the transfer roller 10 is rotated in the same direction by the drive means 8, and the cylindrical object W is rotated in the same direction by the drive means 16 (see arrows in FIG. 1). , the rotation angle is at least 360° for the cylindrical object W, and the transfer roller 10 is rotated at a constant speed at a desired angle depending on the thickness of the transfer coating to be transferred to the cylindrical object W. . The transfer roller lO and the cylindrical object W rotate in the same direction, and the parallelism between them is maintained by the above-mentioned positioning rollers 13, 13', etc. during this rotation, so that the coating area W of the cylindrical object W is A transfer coating film of uniform thickness is formed. In this case, by preheating the cylindrical object W to an appropriate temperature, it is possible to improve the uniformity of the thickness of the transferred coating film.

When the coating of the cylindrical object W is thus completed, the support member 4 moves back in the direction of arrow A', and the slide base 17 moves back in the direction of arrow A'1, so that the positioning roller 13
, 13'', pressure roller 20°20' and transfer roller 10
is separated from the cylindrical object W, and then the cylindrical object W is carried by the carrying unit 15 and carried into an electrostatic drip remover (not shown). In this electrostatic drip remover, a high voltage of about 1 to 10 KV/cm is applied to the discharge electrode to form an electrostatic field between the grounded cylindrical object W and the discharge electrode. Excess paint is removed from W, thereby making the transfer coating film formed on the cylindrical object W completely uniform.

Incidentally, after this, the cylindrical object W is sent to a so-called drying and baking process.

The coating of the cylindrical object W is carried out as described above, but firstly, the film surface of the transfer coating formed on the cylindrical object W is less In addition to being extremely smooth, there is no need for a coating booth, so the configuration of the device can be simplified and the coating time can be further shortened. In addition, masking of the non-painted area Wb of the cylindrical object W is unnecessary, and the number of man-hours required for this is greatly reduced, and the paint to be adhered to the masked portion can be used effectively. Since the paint does not become a mist and scatter, the working environment is also significantly improved.

In addition, the positioning roller 13° 13' in the above embodiment may be eccentrically supported by the arm portions 11a and ll'a of the bracket 11, thereby making it possible to make delicate positional adjustments with respect to the transfer roller IO. It becomes possible. Further, the same effect as described above can be obtained by providing one of the pressing rollers 20 and 20' so as to face the cylindrical object W, and furthermore, the cross-sectional shape thereof can also be formed into a curved shape.

16 and 17 show a second embodiment. This example is a modification of the arrangement direction of the transfer roller 10, etc., and the transfer roller 10 is partially immersed in the paint in the paint container 14. It is supported horizontally so that it can be On the other hand, pad 1
When the cylindrical object W supported by 5c is brought between the positioning rollers 13a, 13a and the vertically movable roller 13'a, it is supported horizontally by these rollers 13a, 13a, and roller 13'a. The coating area W comes into contact with the transfer roller lO. Under such conditions, when the transfer roller lO and the cylindrical object W are rotated in the same direction as shown in the figure, the paint is transferred from the transfer roller 10 to which the paint in the paint container 14 is attached to the cylindrical object W. . Since the cylindrical object W and the transfer roller 10 are arranged horizontally and brought into contact with each other in this way, variations in the thickness of the transfer coating film especially in the longitudinal direction of the cylindrical object W are eliminated, further improving the uniformity of the film thickness. can be done. As shown in FIG. 18, an auxiliary roller 21 is provided that contacts the transfer roller 10 and rotates in the same direction, and as shown in FIG. Alternatively, the paint may be immersed in the paint and applied to the outer surface of the transfer roller 10 via this auxiliary roller 21'. The thickness of the coating film on the cylindrical object W can be made more uniform and appropriate.

Furthermore, in any of the above cases, the transfer roller 10 may have a layer made of an elastic material such as rubber having a constant thickness on its outer periphery.

The cylindrical object W and the transfer roller 10 in the above-mentioned first and second embodiments may rotate in opposite directions.If they rotate in the same direction as described above, the cylindrical object W may rotate in opposite directions. The so-called so-called that can occur along the longitudinal direction of the outer peripheral surface.
Although it is extremely effective for eliminating vertical stripes and forming a uniform coating film, even when the cylindrical object W and the transfer roller 10 are rotated in opposite directions, it is necessary to appropriately adjust the relative tangential speed and contact pressure between them. By selecting the appropriate amount, it is possible to form a uniform and smooth coating film in the same manner as in each of the above embodiments.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to effectively form a coating film having a uniform thickness, especially when coating a cylindrical object, and there are advantages such as improvement in quality and production efficiency.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of the apparatus for explaining the principle of the method of the present invention, FIGS. 2 and 3 are a plan view and partial side sectional view of the main parts of the apparatus of the invention, and FIG. 5 is a side sectional view showing an example of the structure of a transfer roller according to the present invention, FIG. 6 is a longitudinal sectional view showing the structure of the transfer roller, FIGS. 8 is a vertical cross-sectional view showing a modified example of the structure of the transfer roller, FIG. 9 is a side view illustrating the state of paint adhesion on the transfer roller, and FIG. 10 is a cross-sectional view taken along the line xx in FIG. 9. Figure, Figure 11. FIG. 12, FIG. 13, and FIG. 14 are plan views illustrating the functions of the positioning roller and the pressing roller, respectively, according to the present invention;
FIG. 15 is a plan view illustrating the position adjustment mechanism of the positioning roller; FIGS. 16 and 17 are side views and front views of essential parts of the apparatus of the present invention showing an example in which the transfer roller is arranged horizontally;
FIGS. 18 and 19 are side views of essential parts of the apparatus of the present invention, respectively, showing an example in which an auxiliary roller is provided. DESCRIPTION OF SYMBOLS 1...Frame body, 4...Supporting member, 6...Rotating shaft, lO...Transfer roller, 12...Elongated hole, 13
．． 13'...Positioning roller, 14...Paint container, 17...Slide base, 20.20'...
・Press roller, W... Cylindrical object. Fig. 1 Fig. 2 Fig. 1F5 [,-W Fig. 16 Off Fig. 1-8 Fig. 1-9 Fig.

Claims (2)

[Claims] (1) A cylindrical object to be painted and a transfer roller for painting are supported in parallel and relatively so that they can approach and separate from each other, and after coating the surface of the transfer roller with a uniform thickness of paint, the cylindrical object is By bringing the cylindrical object and the transfer roller close to each other, the paint adhering to the transfer roller is brought into contact with the outer peripheral surface of the cylindrical object, and the cylindrical object and the transfer roller are rotated in the same or opposite directions. A method for coating a cylindrical object, comprising forming a coating film of the paint on the outer peripheral surface of the cylindrical object. (2) A transfer roller that is rotatably supported by a support member that is attached to the frame so as to be able to reciprocate along the horizontal direction, and that has an inclined surface formed on the outside and/or inside of its upper edge; A paint container is attached to the frame below the roller so as to be movable up and down and can move toward the transfer roller to immerse the transfer roller into the paint filled inside; a carrier unit capable of holding a cylindrical object to be coated coaxially with the rotation shaft, the support unit having a rotation shaft supported parallel to the transfer roller and capable of holding a cylindrical object to be coated on the same axis as the rotation shaft; , a positioning roller attached to the support member and capable of approaching the cylindrical object gripped by the support unit as the support member is pushed, and a positioning roller that allows the cylindrical object to become parallel to the transfer roller; a pressure roller which can bring the paint adhered to the transfer roller into contact with the outer peripheral surface of the cylindrical object by being sandwiched between the positioning roller and the rotation shaft of the transfer roller and the supporting unit; A coating device for a cylindrical object, comprising: a rotational drive means;