JPH08232097A - Process for producing product - Google Patents

Abstract

PURPOSE: To provide a process for producing a product capable of securing high accuracy in machining. CONSTITUTION: A work is plated by using a processing soln. and then machined to produce a product. In this case, a work temp. controlling stage is provided between the plating stage and machining stage. The work heated to high temp. is cooled to a specified temp. in the temp. controlling stage and then machined. Consequently, the problem that the machining accuracy is lowered due to thermal deformation is eliminated, and high machining accuracy is secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing process of a product in which a machining process is performed following a plating process for plating a work with a processing liquid.

[0002]

2. Description of the Related Art For example, a cylinder block for an internal combustion engine made of an aluminum alloy has its bore surface plated with chrome or the like, but a workpiece activates the surface of the surface to be processed before plating. For the purpose, pretreatment (base treatment) such as degreasing treatment, alkali etching treatment, mixed acid etching treatment, and alumite treatment is performed.

By the way, when the electroplating method using a plating solution such as a chromium plating solution is adopted as the plating treatment,
The work becomes hot due to the reaction heat of the plating solution.

[0004]

By the way, in the case of an engine cylinder block, when the plating process is completed, the bore portion of the cylinder block is honed in the next step. Since the work is subjected to honing processing (while the work is still in the state of being thermally expanded), there is a problem that when the processing is completed and the temperature of the work is reduced, the work shrinks, so that high processing accuracy cannot be obtained.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a manufacturing process of a product capable of ensuring high processing accuracy in a machining process.

[0006]

In order to achieve the above-mentioned object, the invention according to claim 1 is a manufacturing process of a product, in which a machining step is followed by a machining step in which a workpiece is plated with a treatment liquid. A temperature control process for the work is provided between the plating process and the machining process.

According to a second aspect of the invention, in the first aspect of the invention, the temperature control step is a cooling step for cooling the work.

According to a third aspect of the present invention, in the second aspect of the invention, the cooling step is performed while the work is being returned and conveyed.

According to a fourth aspect of the present invention, in the first aspect of the invention, the temperature of the washing water is controlled in the washing step after the plating step in the temperature controlling step.

According to a fifth aspect of the present invention, in the first aspect of the invention, the pre-processing step performed between the plating processing step and the machining step also serves as the temperature control step. And

According to a sixth aspect of the present invention, in the first aspect of the present invention, the machining step includes honing in a series of engine manufacturing processes.

A seventh aspect of the invention is characterized in that, in the first aspect of the invention, a part of the work part is removed before the plating process.

[0013]

According to the present invention, since the workpiece heated to a high temperature by the plating process is cooled to a predetermined temperature through the temperature control process and then subjected to the machining process in the next process, the machining accuracy is not deteriorated due to the thermal deformation. The problem is solved, and high machining accuracy is secured for the work.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

<First Embodiment> FIG. 1 is a schematic view of a plating line for carrying out the method of the present invention, and FIG. 2 is a sectional view showing the structure of each processing portion of the plating line.

The plating line according to the present embodiment is one in which the surface of the bore of the engine cylinder block is plated with chromium or nickel. The plating line is degreased from the left side of FIG. Part B, mixed acid etching part C, alumite processing part D, plating processing part E
And a cooling processing unit F are arranged, and water washing tanks 1-1, 1-2, 2-1 and 2- are provided between these processing units A to F.
2,3-1,3-2,4-1,4-2,5-1,5-2
Are arranged respectively.

The structure of the alkaline etching section B, the mixed acid etching section C, the alumite processing section D and the plating processing section E (the processing sections B to E have the same structure) will be described with reference to FIG.

As shown, a tank 1 containing a processing liquid
A hollow support block 15 is mounted on the support block 4, and two cylinder blocks W (only one is shown) are pressed on the support block 15 by a work holding cylinder 16.

A cylindrical electrode 17 is exposed from below in the bore W ₁ of each cylinder block W.
A liquid supply pipe 18 is connected to. Further, on the side of the support block 15, the bore portion W of the cylinder block W is provided.
A liquid discharge pipe 19 communicating with the inside of ₁ is connected. The liquid supply pipe 18 is made of a copper pipe whose inner surface is lined with rubber, and is electrically connected to a rectifier (not shown).

By the way, the cylinder block W has a spark plug mounting hole W ₂ , an exhaust port W ₃ and a scavenging port W _4.
Is open, but the cylinder block W
Since the treatment liquid is filled in the bore portion W _{1 of} the above, the spark plug mounting hole W ₂ , the exhaust port W ₃ and the scavenging port W ₄
Are closed and sealed by the seal cylinders 20, 21, 22 respectively.

Next, the surface treatment applied to the cylinder block W by the main plating line will be described.
In addition, here, description will be made focusing on a flow on a line of a single cylinder block W.

When the cylinder block W is put into the degreasing treatment section A installed at the left end of the line shown in FIG. 1, the cylinder block W is immersed in the degreasing liquid of the degreasing treatment section A for a predetermined time to perform the degreasing treatment. To be done.

The cylinder block W that has been degreased in the degreasing section A is successively dipped in the washing water in the washing tanks 1-1 and 1-2 to be washed, and then conveyed to the next alkaline etching section B.

In the alkali etching portion B, the surface of the bore portion W ₁ of the cylinder block W is activated by alkali etching. Then, the cylinder block W which has been subjected to the alkali etching has the above-mentioned washing tanks 2-1 and 2-2.
-2 is washed by immersing in the washing water in sequence, then transported to the next mixed acid etching section C, and mixed acid etching is performed in the mixed acid etching section C to form a large number of concave portions on the surface of the bore portion W ₁ .

The cylinder block W which has been subjected to the mixed acid etching treatment is successively dipped in the washing water in the washing tanks 3-1 and 3-2, washed with water, transported to the next alumite treatment section D, and subjected to the alumite treatment there. The surface of the bore portion W ₁ is thinly coated with an oxide film. Then, the cylinder block W which has been subjected to the alumite treatment has the washing tank 4-
It is sequentially dipped in the washing water in 1 and 4-2, washed with water, and conveyed to the next plating processing section E.

In the plated portion E, as shown in FIG. 2, the spark plug mounting hole W ₂ , the exhaust port W ₃ and the scavenging port W ₄ of the cylinder block W are the seal cylinder 2
Blocked by 0, 21, 22 respectively. Then, in this state, the chromium or nickel plating liquid is supplied into the bore portion W ₁ of the cylinder block W via the liquid supply pipe 18 and the electrode 17, and the electrode 17 is electrically supplied from the rectifier (not shown) via the liquid supply pipe 18. Is supplied, and the surface of the cylinder bore W ₁ is plated with chromium or nickel.

In the plating processing section E, the cylinder block W becomes high temperature due to the reaction heat of the plating solution,
The cylinder block W that has reached this high temperature has the above-mentioned washing tank 5-
It is sequentially immersed in the washing water in 1 and 5-2, washed with water, conveyed to the next cooling processing section F, and the temperature thereof is controlled there. Specifically, the cylinder block W is cooled to a predetermined temperature by air cooling such as air blow, water cooling or oil cooling,
The cylinder block W that has fallen to a predetermined temperature is conveyed to a honing unit (not shown), and its bore W ₁ is honed.

As described above, in this embodiment, the cylinder block W, which has been heated to a high temperature by the plating process, is cooled to a predetermined temperature by the temperature control in the cooling processing section F and then subjected to the honing process in the next step. Therefore, the problem of reduction in machining accuracy due to thermal deformation is solved, and high machining accuracy is secured.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIGS. Incidentally, FIG. 3 is a schematic view of a plating line showing a second embodiment of the present invention, and FIG. 4 is a cutaway perspective view of a cooling processing section (return conveyor section) of the plating line. In these figures, FIG. The same elements as those shown in FIG. 2 are designated by the same reference numerals.

The plating line according to the present embodiment is provided with a return conveyor 25 for returning the plated cylinder block W to the original supply side, and cooling equipment is provided in the middle of the return conveyor 25. .

That is, as shown in FIG. 4, a plurality of fans 28 rotatably driven by an electric motor 27 are installed on the cover 26 covering the return conveyor 25 at appropriate intervals.

The cylinder block W, which has been heated to a high temperature by the plating process in the plating process section E, is air-cooled by the fan 28 while being conveyed on the return conveyor 26 and is cooled to a predetermined temperature. High machining accuracy is secured in the honing process which is a process.

<Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIG. Note that FIG. 5 is a configuration diagram of an apparatus that controls the temperature of the washing water in the washing tank.

In this embodiment, the temperature of the cylinder block W is controlled by controlling the temperature of the washing water in the washing tank 5-2 to a predetermined value in the washing step after the plating step. The configuration of the device for carrying out is as follows.

That is, in FIG. 5, 30 is a cooling device, 3
Reference numeral 1 denotes a cooling tank for cooling the washing water. A cooling pipe 33 for circulating a coolant cooled by a cooling device 30 by a pump 32 is immersed in the washing water stored in the cooling tank 31. There is.

A water pipe 34 leading out from the cooling tank 31 is opened above the water washing tank 5-2, and a pump 35, an ion exchanger 36 and a valve 37 are connected in the middle of the water pipe 34. ing. A bypass pipe 38 branches from between the ion exchanger 36 of the water pipe 34 and the valve 37, and the bypass pipe 38 opens above the cooling tank 31 as shown in the drawing.

Further, a return pipe 39 is led out from the overflow portion of the water washing tank 5-2, and the return pipe 39 is opened above the cooling tank 31.

The washing water in the cooling tank 31 is cooled by the cooling pipe 3.
The wash water having a low temperature, which is cooled by the refrigerant flowing through the inside of the pipe 3, is pumped from the water pipe 34 by the pump 35.
2 and is used for cooling the cylinder block W.
Then, the wash water whose temperature has risen due to the cooling of the cylinder block W is returned to the cooling tank 31 through the return pipe 39, is cooled by the refrigerant flowing in the cooling pipe 33 in the cooling tank 31, and is again water pipe 34. Through the water washing tank 5-2
And is used for cooling the cylinder block W, and thereafter, the same operation is repeated. A water temperature sensor may be provided in the cooling tank 31 to maintain the temperature of the washing water in the cooling tank 31 at a predetermined value by feedback control.

As described above, by circulating the wash water, the temperature of the wash water in the wash tank 5-2 is maintained at a constant value, so that the cylinder block W immersed in the wash tank 5-2 is It is cooled to a certain temperature by temperature controlled wash water. Therefore, also in the present embodiment, the cylinder block W which has been heated to a high temperature by the plating process is cooled to a predetermined temperature by the temperature control by the washing water, and is then subjected to the honing process of the next process. The problem of deterioration of accuracy is solved and high machining accuracy is secured for the cylinder block W. <Fourth Embodiment> Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a block diagram showing a series of manufacturing processes of the engine cylinder block.

In this embodiment, the pre-processing step carried out between the plating processing step and the honing processing step also serves as the cylinder block temperature control step.

First, a cylinder block is obtained by casting using an aluminum alloy as a raw material, and then the cylinder block is subjected to reference hole processing and cylinder bore boring processing (processing 1). And these processing (processing 1)
The degreasing->cleaning->plating-> cleaning is performed in this order on the cylinder block which has been finished in the next plating process, and the surface of the cylinder bore of the cylinder block is plated with chromium or nickel.

In the above plating process, as shown in FIG. 7, the cylinder block W is set upside down with the bolts 43 removed and the bearing caps W ₅ removed. The cylinder bore W ₁ of the cylinder block W is sealed by a seal member 41 attached to the lower end of the rod 40 inserted from above, and a liquid supply pipe 42 is inserted from below into the inside of the seal member 41. The surface of the tube 42 is plated with chromium or nickel by the chromium or nickel plating solution supplied from the pipe 42.

Thus, the cylinder block is heated to a high temperature due to the reaction heat of the plating solution, but various processes are applied to this cylinder block in the next pre-processing step. That is, in the preliminary processing step, after the cylinder block has been processed (processing 2) such as an oil hole and a screw hole, the crankshaft bearing cap is assembled and the crankshaft journal of the cylinder block is assembled. The parts are co-processed, and finally the embedding is pressed into the oil hole or the like.

The preliminary machining step also serves as a temperature control step for the cylinder block, and the cylinder block is cooled in the preliminary machining step to reduce its temperature to near room temperature.

Therefore, the cylinder block is subjected to honing in the next step after being sufficiently cooled in the above-mentioned pre-processing step, but in this embodiment as well, the problem of reduction in honing accuracy due to thermal deformation is solved, High machining accuracy is secured for the cylinder block.

Then, the cylinder block for which the honing process has been completed is finally cleaned, and a series of manufacturing processes for the cylinder block is completed here.

<Fifth Embodiment> Next, a fifth embodiment of the present invention will be described with reference to FIG. 8 is a block diagram showing a series of manufacturing processes of the engine cylinder block.

In this embodiment, the pre-processing step is performed on the cylinder block obtained by casting, and the bearing cap of the crankshaft is assembled to the cylinder block before the plating step is started. The crankshaft journal of the block is co-machined.

By the way, since the surface of the bolt to which the bearing cap is assembled is discolored during the degreasing process in the next plating process, in this embodiment, the bolt is removed after the pre-processing process and the bearing cap is removed. It is designed to be removed from the cylinder block.

Then, the cylinder block from which the bearing cap has been removed is plated (degreasing → cleaning →
After being subjected to plating → washing, the cylinder block having a high temperature is cooled in the next cooling step. Then, in the next honing process, the cylinder bore of the cooled cylinder block is honed with high accuracy.

Then, after cleaning the cylinder block after the honing process, if the previously removed bearing cap is reassembled to the cylinder block, a series of manufacturing processes for the cylinder block is completed.

The first to fifth embodiments described above may be implemented in any combination thereof.

[0053]

As is apparent from the above description, according to the present invention, in the manufacturing process of a product in which a machining process is performed subsequent to a plating process for plating a workpiece with a processing liquid, the plating process is performed. Since the temperature control process of the workpiece is provided between the process and the machining process, it is possible to obtain a high machining accuracy in the machining process.

[Brief description of drawings]

FIG. 1 is a schematic view of a plating line showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the configuration of each processing unit of the plating line showing the first embodiment of the present invention.

FIG. 3 is a schematic view of a plating line showing a second embodiment of the present invention.

FIG. 4 is a cutaway perspective view of a cooling processing section (return conveyor section) of a plating line showing a second embodiment of the present invention.

FIG. 5 is a configuration diagram of an apparatus for controlling the temperature of washing water in a washing tank showing a third embodiment of the present invention.

FIG. 6 is a block diagram showing a series of manufacturing processes of an engine cylinder block according to a fifth embodiment of the present invention.

FIG. 7 is a sectional view showing a plating process on an engine cylinder block according to a fifth embodiment of the present invention.

FIG. 8 is a block diagram showing a series of manufacturing processes of an engine cylinder block in a fifth embodiment of the invention.

[Explanation of symbols]

 A Degreasing processing part B Alkali etching part C Mixed acid etching part D Alumite processing part E Plating processing part F Cooling processing part W Cylinder block (work) 25 Return conveyor 28 Fan 30 Cooling device

Claims (7)

[Claims] 1. A temperature control process for a work is provided between the plating process and the machining process in a manufacturing process of a product in which a machining process is performed following a plating process for plating a work using a treatment liquid. The manufacturing process of the product characterized by 2. The manufacturing process of a product according to claim 1, wherein the temperature control step is a cooling step of cooling the work. 3. The manufacturing process of the product according to claim 2, wherein the cooling step is performed while the work is being returned and conveyed. 4. The manufacturing process of the product according to claim 1, wherein in the temperature control step, the temperature of the washing water is controlled in the washing step after the plating treatment step. 5. The manufacturing process of a product according to claim 1, wherein a pre-processing step performed between the plating processing step and the machining step also serves as the temperature control step. 6. The product manufacturing process according to claim 1, wherein the machining process includes honing in a series of engine manufacturing processes. 7. The process of manufacturing a product according to claim 1, wherein a part of a work part is removed before the plating process.