JP3267826B2 - Plating method for inner circumferential surface of engine cylinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for plating an inner peripheral surface of a cylinder of an engine of an automobile or the like.

[0002]

2. Description of the Related Art In an engine of an automobile or the like, a cylinder block and a bearing cap, which are separately formed in advance, are connected to each other to support a crankshaft. In such an engine, it is generally known that a sliding surface is formed by plating an inner peripheral surface of a cylinder of a cylinder block.

Conventionally, in manufacturing such an engine, as shown in the process diagram of FIG. 5, first, a cylinder block and a bearing cap are separately manufactured by casting and various processes (process). And forming a crankshaft support portion and the like on the combined body by co-processing (step). And when co-processing is completed,
After being disassembled again into the cylinder block and the bearing cap, the bearing cap is transferred to the final assembly step (step) through the cleaning step (step). On the other hand, the cylinder block shifts to a surface treatment step (step) in order to apply plating to the inner peripheral surface of the cylinder, and then to a final assembling step (step) through a honing finishing step (step) and a cleaning step (step) for the inner peripheral surface of the cylinder. Step). Then, in a final assembly process (process), the engine is completed by connecting the cylinder block and the bearing cap while assembling various components such as a crankshaft.

In this manufacturing method, the surface treatment step is performed after the co-processing step because chips and the like generated at the time of the co-processing can be washed off by using a washing operation required for the surface treatment. This is because it is reasonable.

[0005]

By the way, in the conventional surface treatment process (the pretreatment process for plating and the plating process), in general, the treatment is performed in a state where the object to be treated is immersed in a treatment bath. Surface treatment is performed by immersion on the entire surface.In this case, if the bearing cap is connected to the cylinder block, the bearing cap is unnecessarily pre-treated or the amount of the processing solution such as plating solution taken out increases. Or inconvenience. Therefore, the cylinder block and the bearing cap are disassembled after the co-processing as described above, and only the cylinder block is sent to the surface treatment step. However, in this case, there is a problem that erroneous assembly is likely to occur.

That is, after the co-machining, the cylinder block and the bearing cap have a one-to-one correspondence, that is, a relationship in which the mating parts to be connected to each other are specified for each product. Corresponding cylinder blocks and bearing caps need to be joined, but disassembling them before plating and handling cylinder blocks and bearing caps separately for a long time until the final assembly of the engine can lead to When a typical engine is assembled, erroneous assembly in which parts other than the corresponding ones are connected to each other is likely to occur.

Therefore, in order to shorten the period in which the cylinder block and the bearing cap are separately handled, it is conceivable that the cylinder block and the bearing cap are combined again and sent to the honing finishing step immediately after the surface treatment step. In this case, the number of manufacturing steps increases, which is not preferable. In addition, there is still a possibility that erroneous assembly may occur at this stage due to disassembly and bonding performed before and after the surface treatment step.

The present invention has been made by paying attention to the fact that a high-speed plating technique has been developed in which a plating solution is flowed between a surface to be plated and an electrode to energize the electrode, thereby increasing a plating speed. It is an object of the present invention to provide a plating method for an inner peripheral surface of a cylinder of an engine, which can more efficiently perform engine production.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a cylinder block and a bearing cap are separately formed, and these are integrally joined to co-process a support portion for a crankshaft. In the plating step, the combined body of the cylinder block and the bearing cap is placed on the cylinder block support of the surface treatment section, and the flow is formed on the cylinder block support. The path forming member is caused to protrude into the cylinder of the cylinder block from the opening opposite to the side to which the bearing cap is coupled, thereby forming a path for flowing the processing liquid inside the cylinder, and the bearing cap is formed. While the opening on the side opposite to the side where the A sealing member is inserted into the cylinder from the opening on the side where the sealing cap is coupled to seal the opening, and in this state, the processing liquid is caused to flow through a passage in the cylinder formed by the flow path component. The inner peripheral surface of the cylinder is subjected to a surface treatment.

[0010]

According to the present invention, since the processing liquid is supplied and processed only in the cylinder of the cylinder block, the bearing cap is unnecessarily pre-processed or the amount of processing liquid taken out increases. It does not cause adverse effects such as. Therefore, in the production of the engine, after co-machining, the process shifts to a step of plating while leaving the combined body of the cylinder block and the bearing cap, and while processing is performed on the inner peripheral surface of the cylinder of the cylinder block, It is possible to wash the combined body together in the processing liquid washing operation in the above and to wash away chips and the like generated in the co-processing.

[0011]

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

FIG. 1 is a view schematically showing a manufacturing process of an engine to which a method for plating an inner peripheral surface of a cylinder of an engine according to the present invention is applied. In the manufacturing process of the engine shown in this figure, first, a main part of the engine is manufactured by casting (casting process A). The main part of the engine is a cylinder block 1 in which a cylinder component having four cylinders 1a arranged in parallel and a skirt-shaped crankcase are integrally formed.
And the bearing cap 2 attached to the crankcase portion is manufactured separately in the casting process A, and the process is shifted to the machining process B.

In the processing step B, the cylinder block 1
The bearing cap 2 and the bearing cap 2 are each subjected to machining such as drilling, so that mounting holes for various components, oil passages, and the like are formed in the cylinder block 1 and the bearing cap 2. After machining, a blind plug is press-fitted into an oil passage or the like of the cylinder block 1 as necessary (not shown).

Thereafter, the cylinder block 1 and the bearing cap 2 are connected, and the combined body 3 is processed such as a crankshaft support portion (co-processing step C). By performing the co-processing on the combined body 3 in this manner, the cylinder block 1 and the bearing cap 2 have a one-to-one correspondence, and the accuracy of the crankshaft supporting portion and the like is ensured. Has become.

When the co-machining step C is completed, the combination 3 is transferred to a surface treatment step D in order to apply plating to the inner peripheral surface of each cylinder 1a of the cylinder block 1.

In the surface treatment step D, plating and pretreatment for plating are performed. Specifically, a degreasing treatment, an alkali etching treatment, a mixed acid etching treatment, an alumite treatment, a plating treatment, and a drying treatment are performed in this order. Therefore, in the surface treatment step D, a treatment section for performing each of these treatments is provided, and a water washing section for washing off the treatment liquid or the like is provided between the treatment sections. Are sequentially transferred to each processing section and washing section, so that each cylinder 1
The plating is applied to the inner peripheral surface of a.

In particular, in the surface treatment step D of the present embodiment, the processing in each processing section is performed by a high-speed processing apparatus. It will be described as.

FIGS. 2 and 3 schematically show the structure of the plating section Da. In these figures, the plating section D
a includes a plating apparatus main body 10 and a sealing apparatus 30.

A support block 12 as a cylinder block support is provided on a base 11 of the plating apparatus main body 10, and the above-mentioned combined body 3 is supported on the support block 12. Specifically, the support block 12
In a state where the head side is turned downward (upside down as compared with the state when mounted on a vehicle), the combined body 3 is
2, the lower opening of each cylinder 1 a of the cylinder block 1 is closed by the support block 12 in this state.

A processing liquid outlet passage 13 is formed in the support block 12 at a position below the combination 3.
On the upper surface of the support block 12, an opening 13a is provided at a position corresponding to each cylinder 1a of the cylinder block 1 so as to communicate with the processing liquid lead-out passage 13. Then, in a state where the combined body 3 is supported on the support block 12 as described above, the lower openings of the cylinders 1a and the openings 13a match.

Further, in the plating apparatus main body 10, an electrode 14 serving also as a flow path component is disposed at a position corresponding to each cylinder 1a of the cylinder block 1 in the combined body 3 supported as described above. . This electrode 14 is shown in FIG.
As shown in FIG.
And a large number of pellets 18 made of nickel as a soluble anode material are stored in the pellet storage section 15. The electrode main body includes an inner cylindrical portion 16 made of a metal pipe and an outer cylindrical portion 17 made of a porous metal plate or the like, and a pellet storage portion 15 is formed between the inner and outer cylindrical portions 16 and 17. At the same time, a cover 16a made of a porous metal plate or the like is attached to the upper end of the inner cylindrical portion 16.

The electrode 14 is mounted on a holder 19 mounted on the base 11 via a cylindrical mounting member 20 and penetrates through the processing liquid outlet passage 13 and protrudes upward from the opening 13a. . Then, in a state where the combined body 3 is supported on the support block 12 as described above,
The electrode 14 protrudes into each cylinder 1a of the cylinder block 1, and a constant gap is maintained between the outer peripheral surface of the electrode 14 and the inner peripheral surface of the cylinder. Thus, channels 21 and 22 communicating with each other at the upper portion via the cover 16a are formed inside and outside the electrode 14 (inside the inner cylindrical portion 16) in each cylinder 1a, and the outer channel 22 Communicates with the processing liquid outlet passage 13.

A through hole is formed in the holder 19, and the through hole, the mounting member 20, and the support block 1 are formed.
A processing liquid introduction passage 23 communicating with the flow path 21 inside the electrode 14 is formed with the internal space of the other members constituting the second member 2.

Although not shown, the plating apparatus body 10 has a supply / drainage system for supplying a plating solution,
An electric system for applying a voltage to the electrodes 14 and the like during processing is provided. In brief, the plating solution supply / discharge system is configured such that the plating solution is sent from the plating solution storage tank to the processing solution introduction passage 23 via a pump,
After passing through 22, the processing solution outlet passage 13 is configured to be recovered in a plating solution storage tank via a plating solution recovery pipe. Further, the electric system is configured such that the electrode 14 is connected to the positive side of the power supply circuit, and the coupling body 3 is connected to the negative side of the power supply circuit via the sealing device 30, so that the electrode 14 and the cylinder block are connected. 1 is applied.

On the other hand, the sealing device 30 is disposed above the plating apparatus main body 10 configured as described above.

The sealing device 30 includes each cylinder 1a
Specifically, each member as a sealing jig inserted into an upper opening which is an opening opposite to the support block 12 is provided. A movable plate 31 provided with a cylindrical mounting member 32 is provided at a position corresponding to each of the cylinders 1a, and the movable plate 31 can be moved up and down by operating means (not shown). Each mounting member 32 is provided at its lower end with a hollow frustoconical sealing member 33 made of an elastic material such as rubber, and a movable rod 34 integrally provided at its lower end with a disc-shaped seal pressing member 34a. Is pierced. The movable rod 34 is structured so that it can be stroked in two stages by an air cylinder (not shown), whereby the seal holding member 34a is moved stepwise to an upper end position, an intermediate position, and a lower end position. I am getting it. When the seal pressing member 34a is at the rising end position, the seal member 33 is expanded into an umbrella shape by the compressive force of the mounting member 32 and the seal pressing member 34a, while the seal pressing member 34a is When the seal member 33 is at the descending end position, the diameter of the seal member 33 is reduced by its own weight, and the seal member 33 is in a semi-expanded state when the seal pressing member 53a is at the intermediate position.

In the processing in the plating section Da, first, the sealing device 30 is operated in a state where the assembly 3 is mounted on the support block 12, so that each of the cylinder blocks 1 is operated. The opening of the cylinder 1a on the side opposite to the support block 12 is sealed.

More specifically, when the movable plate 31 is lowered, the seal member 33 is inserted into each cylinder 1a through a through hole formed in the bearing cap 2 and the crankcase portion of the cylinder block 1. And is disposed directly above the electrode 14. At this time, the seal holding member 34a is held at the lower end position, so that the seal member 33 is reduced in diameter and narrowed to such an extent that it can easily pass through the through hole of the bearing cap 2 and the crankcase portion. waiting.

When each seal member 33 is disposed in each cylinder 1a of the cylinder block 1, the seal holding member 34
Is raised to the intermediate position, and a semi-expanded state in which the outer peripheral portion of each seal member 33 is not in contact with the inner peripheral surface of the cylinder 1a. Then, again, each seal member 33 is connected to the electrode 14.
After the movable plate 31 is lowered so as to be disposed immediately above the seal member 34a, the seal holding member 34a is raised to the raised end position, whereby the seal member 33 is completely spread as shown in FIG. Each cylinder 1a
Is sealed.

In this way, when the sealing of the cylinder 1a by the sealing device 30 is completed, the pump connected to the plating solution storage tank (not shown) is operated to supply the plating solution to the plating device main body 10. . As a result, the plating solution flows into the processing solution introduction passage 23, and the passage 21,
22, the plating solution flows out of the processing solution outlet passage 13 and flows along the inner surface of the cylinder 1a, which is the surface to be plated, while a voltage is applied between the electrode 14 and the cylinder block 1 to increase the speed. Plating is performed.

In this case, since the upper opening of each cylinder 1a is sealed by the sealing member 33 of the sealing device 30, the plating solution flowing in each cylinder 1a is outward from the cylinder 1a, that is, the bearing cap 2 side. High-speed plating is performed satisfactorily in a state in which overflowing is surely prevented.

The structure of the seal device 30 is not limited to the above-described one. For example, a seal body or the like that expands with air may be used.

The above is the description of the plating section, but the same apparatus as the plating section Da is also used in the pretreatment sections such as the degreasing treatment, the alkali etching treatment, the mixed acid etching treatment and the alumite treatment section. The processing is performed at high speed. In this case, since the electrode 14 is unnecessary in the other processing units, a substantially cylindrical member similar to the electrode 14 is attached to the support block 12 to form a flow path. Also,
In the pre-processing section, the sealing device may be simplified.

In the surface treatment step D, a washing section is provided between the treatment sections as described above, and a treatment for washing off unnecessary treatment liquid adhering to the cylinder block 1 is performed. In such a case, such a cleaning is performed on the whole of the combined body 3 so that the unnecessary processing liquid attached to the cylinder block 1 and the chips generated in the co-processing step C are washed off together. It is.

When the plating of each cylinder 1a of the cylinder block 1 is completed in the surface treatment step D in this way, the combined body 3 is subjected to the honing finish step E.
And a honing finish is applied to the inner peripheral surface of each of the plated cylinders 1a. Specifically, after the combined body 3 is placed on a predetermined work table of a honing machine, and a honing head is inserted into each cylinder 1a, the honing head is rotated to thereby rotate the inner peripheral surface of the cylinder 1a. Is polished.

The combined body 3 which has been subjected to the honing finish processing
Is transferred to a cleaning step F to wash off chips and the like generated in the honing finishing process, and then disassembled into a cylinder block 1 and a bearing cap 2.

The disassembled cylinder block 1 and the bearing cap 2 are shifted to a final assembling step G, where the various components such as the crankshaft 4 are assembled again while being assembled together. Complete.

As described above, according to the production of the engine of the above embodiment, the combined body 3 which has been processed in the co-machining step C is transferred to the surface treatment step D without any change.
Since the cylinder block 1 and the bearing cap 2 are integrally washed in the washing operation performed in step 1, it is not necessary to wash the bearing cap 2 alone after performing the co-processing. Therefore, it is possible to reduce the number of cleaning steps for the bearing cap alone in the engine manufacturing process, and to more efficiently manufacture the engine.

By the way, as described above, the cylinder block 1
When the process proceeds to the surface treatment step D while the bearing cap 2 and the bearing cap 2 are integrated, there is a concern that the bearing cap 2 is unnecessarily pre-treated or that the amount of the processing solution such as a plating solution taken out increases. However, in the surface treatment step D, as described above, the upper opening of each cylinder 1a, that is, the opening on the side to which the bearing cap 2 is attached is sealed by the sealing device 30,
In this state, the processing liquid is supplied only to the inner peripheral surface of each cylinder 1a and the processing is performed. Therefore, the processing liquid adheres to the bearing cap 2 to perform unnecessary preprocessing, or the amount of the processing liquid taken out is reduced. There is no adverse effect such as increase.

Further, since the combined body 3 which has been processed in the co-machining step C can be directly transferred to the surface treatment step D, the period for separately handling the cylinder block 1 and the bearing cap 2 after the co-machining is reduced. Therefore, as a result of the co-machining, the cylinder block 1 and the bearing cap 2 which are brought into a one-to-one correspondence can better prevent the occurrence of an assembly failure when the cylinder block 1 and the bearing cap 2 are assembled to another cylinder block or a bearing cap. It becomes possible. In particular, in this embodiment, after co-machining the cylinder block 1 and the bearing cap 2 in the co-machining step C, the cylinder block 1 and the bearing cap 2 are always integrated until the final assembly step G; Therefore, there is an advantage that erroneous assembly in the final assembly process G is reliably prevented.

The above-described embodiment schematically describes an example of an engine manufacturing process to which the method for plating the inner peripheral surface of the cylinder of the engine according to the present invention is applied. These operations can be appropriately changed without departing from the spirit of the present invention.

[0042]

As described above, according to the method for plating the inner peripheral surface of the cylinder of the engine of the present invention, in the plating step, the processing liquid is supplied only into the cylinder of the cylinder block to perform the processing. Therefore, even if the process shifts to the plating process with the combined cylinder block and bearing cap in the production of the engine, the bearing cap is unnecessarily pre-processed or the amount of processing liquid taken out increases. The combined body can be integrally washed in the treatment liquid washing operation performed in the plating step without causing the adverse effects of the above. Therefore, unlike the related art, there is no need to disassemble the combined body after the co-machining and wash the bearing cap alone, thereby making it possible to manufacture the engine more rationally.

In addition, since the cylinder block and the bearing cap, which are in a one-to-one correspondence, can be handled after being co-processed for a longer period of time, erroneous operations during the final assembly of the engine can be effectively prevented. Can be.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a process of manufacturing an engine to which a plating method for an inner peripheral surface of a cylinder of an engine of the present invention is applied.

FIG. 2 is a front view (partial sectional view) showing an apparatus applied to a plating section in a plating step.

FIG. 3 is a side view (partial sectional view) showing an apparatus applied to a plating section in a plating step.

FIG. 4 is a side view (partial cross-sectional view) of a plating processing section for explaining processing contents.

FIG. 5 is a view schematically showing a manufacturing process of a conventional engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder block 1a Cylinder 2 Bearing cap 3 Combined body 4 Crankshaft 10 Plating apparatus main body 30 Sealing apparatus A Casting step B Processing step C Co-processing step D Surface treatment step Da Plating processing part E Honing finishing step F Cleaning step G Final assembly step

Claims (1)

(57) [Claims] 1. A method in which a cylinder block and a bearing cap are separately formed, these are integrally joined, a support portion for a crankshaft and the like are co-processed, and then plating is performed on the inner peripheral surface of the cylinder of the cylinder block. In the plating step, the combined body of the cylinder block and the bearing cap is placed on the cylinder block support of the surface treatment unit, and the flow path component protruding from the cylinder block support is attached to the bearing cap. By projecting into the cylinder of the cylinder block from the opening opposite to the side where the bearing cap is coupled, a path for flowing the processing liquid inside the cylinder is formed, and the side opposite to the side where the bearing cap is coupled. While the opening is closed by the cylinder block support, and the bearing cap is connected. A sealing member is inserted into the cylinder from the opening on the side to seal the opening, and in this state, the processing liquid is caused to flow through a passage in the cylinder formed by the flow path constituent member, and the surface is formed on the inner peripheral surface of the cylinder. A plating method for an inner peripheral surface of a cylinder of an engine, wherein the plating is performed.