JPH0523575Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application This invention relates to a dipping jig used for surface treatment of precision drums such as cylinder heads for DATs, VTRs, etc.

Conventional technology For example, cylinder heads for DAT are generally made of A-Si alloy containing a high percentage of Si to prevent wear due to contact with magnetic tape, but the surface may corrode due to environmental factors. , may cause discoloration. For example, in automotive DATs in particular, rapid temperature changes can cause condensation, which easily corrodes and discolors the cylinder head surface. Therefore, surface treatments such as chromate treatment are sometimes performed on the cylinder head in order to improve the moisture resistance of the surface.

Conventionally, a dipping jig as shown in FIGS. 5 and 6 has been used for this surface treatment. This immersion jig has a drum support member 52 erected at the intertwining part of support bars 51, 51 arranged in a lattice pattern forming the bottom of the jig frame. The cylinder head 56 is formed to have an upper rod-like part 53 with a circular cross section that can be fitted into the shaft hole 57 of the cylinder head 56, and a lower support part 54 with a short cylindrical shape or a short cylindrical shape that supports the lower surface of the cylinder head 56. During surface treatment, the upper rod-shaped portion 53 is fitted into the shaft hole 57 of the cylinder head 56, and the lower surface of the cylinder head 56 is placed and supported on the lower support portion 54, and then immersed in the treatment liquid. It is done by soaking.

Problems to be Solved by the Invention However, with the above-mentioned conventional immersion jig, the processing liquid does not drain well and the amount of processing liquid taken out is relatively large, which not only causes early deterioration of the processing liquid, but also causes damage to the cylinder head. There was a problem that residual liquid adhering to the surface of 56 easily caused stains and stains on the surface.

Furthermore, in the surface treatment using the above-mentioned dipping jig, the cylinder head 56 lifts up and separates from the drum support member 52 during the process of dipping the jig in the treatment liquid, and falls, causing damage to the cylinder head 56. There were also problems that could occur.

The above-mentioned stains, dirt, and scratches can be fatal to the cylinder head 56, which is a precision component, and it is important to solve such problems.

The object of this invention is to provide a dipping jig for surface treatment of precision drums such as cylinder heads, which can solve the above-mentioned problems.

Means for Solving the Problems For the above purpose, this invention has a drum support member erected at the intertwining part of support bars arranged in a lattice form forming the bottom of the jig frame, and the drum support member has a cylinder. It has an upper rod-shaped fitting part that can be fitted from the upper end into the shaft hole of a precision drum such as a head, and a lower support part that is connected to the lower part of the upper rod-shaped fitting part and has a larger diameter than the upper rod-shaped fitting part. The cross-sectional shape of the rod-shaped fitting portion is formed into an irregular cross-sectional shape that makes point contact with the circumscribed circle, while the shoulder surface of the lower support portion is inclined diagonally downward toward the outside, and The gist of the present invention is a dipping jig for surface treatment of precision drums such as cylinder heads, characterized in that a drainage groove extending radially outward is formed on the shoulder surface.

In actual use, the above-mentioned jigs are used by stacking a plurality of jigs vertically in multiple stages. Therefore, the jig frames are made to be stackable so that they do not move relative to each other during stacking, and
In order to prevent the precision drum from falling off the drum support member when immersed in the processing liquid, it is preferable to provide support that forms the upper end of the drum support member of the lower jig frame and the bottom of the upper jig frame. The distance between the crosspiece and the lower surface is set to be shorter than the height of the precision drum.

As a result of the above, the cross-sectional shape of the upper rod-shaped fitting part of the drum support member is formed into an irregular cross-sectional shape that makes point contact with the circumscribed circle, so that the upper rod-shaped fitting part fits into the shaft hole of the precision drum. In the combined state,
The inner circumferential surface of the shaft hole and the rod-shaped support portion are in line contact with each other, and a gap is formed through which the processing liquid can flow. Moreover, since the contact is made in a line, there is no possibility that a large amount of processing liquid remains in the vicinity of the contact area due to capillary action. In addition, the lower support part that supports the precision drum has a shoulder surface that is inclined diagonally downward toward the outside, and a drainage groove that extends radially outward is formed on the shoulder surface. The lower surface also makes line contact with the above shoulder surface,
A large amount of processing liquid does not remain between them due to capillary action, and the processing liquid flowing down from between the inner circumferential surface of the shaft hole of the precision drum and the upper rod-shaped fitting part is drained into the inclined drainage groove. It flows out smoothly through the tube. As a result of the above, the processing liquid is prevented from dripping from the precision drum after immersion, and the removal of the processing liquid can be suppressed.

Example The illustrated embodiment will be described below.

As shown in FIG. 1, the surface treatment dipping jig 1 includes a jig frame 2 with drum support members 3 erected at the bottom thereof.

This jig frame 2 is formed into a shallow box shape with side walls 4 of a predetermined height around the periphery, and the bottom is made up of vertical and horizontal support bars 5 arranged in a grid pattern. The support members 3 are provided upright at each intertwined portion of the support bars 5. In order to facilitate mounting of the precision drum 9 on the drum support member 3, the support bars 5 are arranged so that their intertwined portions are maintained at appropriate intervals.

As shown in FIG. 2, the drum support member 3 includes an upper bar-shaped fitting part 6 that can be fitted into the shaft hole 10 of the precision drum 9 from the upper end, and an upper bar-shaped fitting part 6 that is connected to a lower part of the upper bar-shaped fitting part 6. The lower support portion 7 has a larger diameter than the upper rod-shaped fitting portion 6. The precision drum 9 has an upper bar-shaped fitting part 6 in its shaft hole 10.
and connect the inner peripheral edge of the lower surface to the shoulder surface 8 of the lower support part 7.
It is supported by the drum support member 3 in such a manner that it is supported by the drum support member 3.

The cross-sectional shape of the upper rod-shaped fitting part 6 needs to be formed into an irregular cross-sectional shape that makes point contact with the circumscribed circle, and therefore, for example, as shown in FIGS. It is formed into a polygonal cross-sectional shape such as a regular hexagon. By providing such a cross-sectional shape, when the upper bar-shaped fitting part 6 is fitted into the shaft hole 10 of the precision drum 9, the shaft hole 1
A gap 15 is formed between the inner circumferential portion of the cylindrical member 0 and the rod-shaped support portion 6 so that the processing liquid can freely flow therethrough. Moreover, since the two are in line contact, there is no possibility that a large amount of processing liquid remains in the vicinity of the contact area due to capillary action. In addition, since it is in line contact,
The treatment liquid sufficiently spreads to the inner circumferential surface of the shaft hole 10 of the precision drum 9, making it possible to perform surface treatment without unevenness.

Note that as the polygonal cross-sectional shape, a triangular to octagonal shape can be suitably adopted. If the shape exceeds the octagonal shape, the gap 15 becomes smaller and the flow rate of the processing liquid becomes smaller, and the amount of processing liquid remaining due to capillary action increases, resulting in a tendency for more processing liquid to be taken out. Therefore, it is undesirable.

The upper rod-shaped fitting part 6 can also be formed into a star-shaped cross-sectional shape in which each side of an equilateral triangle, square, or regular hexagon is depressed inward, as shown in FIGS. . In this case, it is possible to secure a larger gap 15 between the inner circumference of the shaft hole 10 and the upper rod-shaped fitting part 6, thereby improving the communication property of the processing liquid, and at the same time making contact with the inner circumference of the shaft hole 10. By increasing the contact angle at the corners, the amount of processing liquid remaining due to capillary action can be further reduced, and the drainage performance of the processing liquid can be improved.

As shown in FIG. 2, the shoulder surface 8 is inclined obliquely downward toward the outside, and has a drain groove 11 formed therein that extends radially outward. As a result, the precision drum 9 is brought into line contact with the shoulder surface 8 on the lower surface, and a large amount of processing liquid does not remain between them due to capillary action, and the processing solution is sufficiently applied to the lower surface of the precision drum 9. Furthermore, the processing liquid flowing down from between the inner peripheral surface of the shaft hole 10 of the precision drum 9 and the upper rod-shaped fitting part 6 passes through the inclined drainage groove 11. It is smoothly leaked to the outside. Furthermore, since the shoulder surface 8 is inclined diagonally downward toward the outside as described above, there is an effect that the precision drum 9 can be stably supported. In addition, the drain groove 11
The size, number, etc. of the tubes are appropriately set in consideration of the flowability of the processing liquid.

Further, as shown in FIG. 2, it is desirable that the tip of the upper bar-shaped fitting portion 6 be formed into a tapered shape 13.
By doing so, the shaft hole 10 of the precision drum 9 and the upper rod-shaped fitting portion 6 can be easily fitted, and this can contribute to improving the overall work efficiency of surface treatment.

The drum support member 3 is preferably made of a material that does not damage the precision drum 9 and has good durability against the processing liquid. For example, precision drum 9
When the drum support member 3 is made of a Si-A alloy containing a high percentage of Si and is subjected to chromate treatment, it is preferable that the drum support member 3 is made of a hard synthetic resin, such as Bakelite resin.

Further, the jig frame 2 can be stacked in multiple stages in the vertical direction, as shown in FIGS. 1 and 4. In order to prevent relative movement during stacking and maintain a stable stacked state, displacement regulating pieces 16 are provided on the upper outer surface of each side wall 4 of the jig frame 2 in an upwardly protruding state. It is being As a means for preventing relative movement when the jig frames 2 are stacked, a displacement regulating piece 16 as described above is used.
In addition to using this method, other known means may be employed, such as forming stepped portions that fit into each other at the upper and lower ends of the side wall 4. In addition, the jig frame 2 has a distance t ₁ between the upper end of the drum support member 3 and the lower surface of the support bar 5' that constitutes the bottom of the jig frame 2' stacked on the upper stage, and the height t of the precision drum 9. It is formed to be shorter than ₂ . By doing this, even if the precision drum 9 floats up during the process of being immersed in the processing liquid, it will come off from the drum support member 3 by coming into contact with the lower surface of the support bar 5' of the jig frame 2'. It is prevented from falling off.

Effects of the invention As described above, in this invention, the cross-sectional shape of the upper rod-shaped fitting part of the drum support member is formed into an irregular cross-sectional shape that makes point contact with the circumscribed circle, and the shoulder surface of the lower support part is formed in an outer shape. It is slanted diagonally downward toward the direction of the drum, and has drain grooves formed on the shoulder surface that extend outward in the radial direction. The processing liquid can be easily drained, and the removal of the processing liquid can be suppressed, thereby preventing early deterioration of the processing liquid. Similarly, since the liquid drips well, it is possible to prevent stains and stains caused by liquid remaining on the precision drum.

Further, as claimed in claim (2), the jig frames are formed so that they can be stacked vertically in multiple stages while preventing relative movement, and when the jig frames are stacked, the upper end of the drum support member of the lower jig frame and the upper By setting the distance between the lower surface of the support bar that makes up the bottom of the jig frame shorter than the height of the precision drum, even if the precision drum rises when the jig is immersed in the processing liquid, the upper stage The range of elevation is restricted by the lower surface of the support crosspiece of the jig frame, so that the precision drum does not separate from the drum support member, and scratches caused by such separation can be prevented.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing an embodiment of the dipping jig for surface treatment of this invention, Figure 2 is a side view of the drum support member, Figures 3A to 3F are plan views of the upper rod-shaped fitting part, and Figure 4 is a cross-sectional view showing how the jigs are stacked;
FIGS. 5 and 6 are a partial perspective view and a partial side view, respectively, showing a conventional surface treatment dipping jig. 1...Immersion jig for surface treatment, 2...Jig frame, 3
...Drum support member, 5...Support bar, 6...Upper rod-shaped fitting part, 7...Lower support part, 8...Shoulder surface, 9
... Precision drum, 10 ... Shaft hole, 11 ... Drainage groove, 16 ... Misalignment regulating piece.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A drum support member is erected at the intertwined part of support bars arranged in a grid pattern forming the bottom of the jig frame,
The drum support member includes an upper rod-shaped fitting part that can be fitted from the upper end into the shaft hole of a precision drum such as a cylinder head, and a rod-shaped fitting part connected to a lower part of the upper rod-shaped fitting part and having a diameter larger than that of the upper rod-shaped fitting part. The upper rod-shaped fitting part has a cross-sectional shape of an irregular cross-sectional shape that makes point contact with the circumscribed circle, while the shoulder surface of the lower support part faces outward. A dipping jig for surface treatment of precision drums such as cylinder heads, characterized in that the jig is inclined diagonally downward and has a drainage groove formed in the shoulder surface and extending radially outward. (2) The jig frames are formed so that they can be stacked vertically in multiple stages to prevent relative movement, and when the jig frames are stacked, the upper end of the drum support member of the lower jig frame and the upper jig frame 2. The dipping jig for surface treatment of a precision drum such as a cylinder head according to claim 1, wherein the distance between the supporting bar constituting the bottom and the lower surface is set shorter than the height of the precision drum.