JPH08232094A - Method for plating inner peripheral surface of cylinder of engine - Google Patents

Abstract

PURPOSE: To rationally execute production of an engine. CONSTITUTION: A cylinder block 1 and a bearing cap 2 are produced in a production stage A and a fabricating stage B. A coupled body 3 is obtd. by integrally coupling both in an assembling stage C. The coupled body 3 is subjected to co-fabrication in order to form crank shaft supporting parts, etc., in a co- fabricating stage C and thereafter, the coupled body 3 is transferred to a surface treating stage D. The coupled body 3 is placed on a supporting block 12 of a plating treating section Da in the surface treating stage D. Electrodes 14 are plunged into the cylinder 1a of the cylinder block 1 from the aperture on the side opposite to the side coupled with the bearing cap 2 and the aperture on the side coupled with the bearing cap 2 is sealed by a sealing device 30. A plating liquid is made to flow in the cylinder 1a in this state and the inner peripheral surface of the cylinder 1a is subjected to the surface treatment. The coupled body 3 is integrally washed in the washing operation in the surface treating stage D after the completion of the treatment.

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 the inner peripheral surface of a cylinder of an engine such as an automobile.

[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 joined together to support a crankshaft. In such an engine, it is generally known that the cylinder inner peripheral surface of the cylinder block is plated to form a sliding surface.

Conventionally, in the manufacture of such an engine, as shown in the process chart of FIG. 5, first, a cylinder block and a bearing cap are manufactured separately by casting and various processes (process), and then these are manufactured. And the crankshaft supporting portion and the like are formed on the combined body by co-processing (step). And when the co-processing is completed,
After the cylinder block and the bearing cap are disassembled again, the bearing cap is transferred to the final assembly process (process) through the cleaning process (process). On the other hand, the cylinder block moves to a surface treatment process (process) to plate the inner peripheral surface of the cylinder, and then undergoes a honing finishing process (process) for the inner peripheral surface of the cylinder and a final assembly process (process) through a cleaning process (process). Process). Then, in the final assembly process (process), the engine is completed by connecting the cylinder block and the bearing cap while assembling various parts such as the crankshaft.

In this manufacturing method, the surface treatment step is performed after the co-processing step because it is possible to wash off the chips and the like generated during the co-processing by utilizing the cleaning work necessary for the surface treatment. Because it is rational.

[0005]

By the way, in the conventional surface treatment process (pretreatment process for plating and plating process), generally, the treatment is performed while the object to be treated is immersed in the 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 may be unnecessarily pretreated or the amount of processing liquid such as plating liquid taken out may increase. There are inconveniences such as Therefore, as described above, the cylinder block and the bearing cap are disassembled after co-processing and only the cylinder block is sent to the surface treatment step. However, this causes a problem that misassembly is likely to occur.

That is, after co-machining, the cylinder block and the bearing cap have a one-to-one correspondence, that is, the partner to be coupled to each other is specified for each product. It is necessary to connect the corresponding cylinder block and bearing cap, but if you handle the cylinder block and bearing cap separately for a long period of time before disassembling them before plating and finally assembling the engine, Erroneous assembly in which components other than those corresponding to each other are coupled to each other during the assembly of a typical engine is likely to occur.

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

The present invention has been made paying attention to the fact that a high-speed plating technique has been developed in which a plating solution is caused to flow between a surface to be plated and an electrode to energize the electrode to thereby increase the plating rate. It is an object of the present invention to provide a method for plating the inner peripheral surface of the cylinder of an engine, which enables more rational and consistent engine manufacturing.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a cylinder block and a bearing cap are separately formed, and they are integrally connected to each other to co-machine a supporting portion for a crankshaft and the like. A method of plating a surface, wherein in the plating step, the combined body of the cylinder block and the bearing cap is placed on the cylinder block support part of the surface treatment part, and the flow is projected on the cylinder block support part. A path for flowing the treatment liquid inside the cylinder is formed by causing the passage forming member to project into the cylinder of the cylinder block from the opening on the side opposite to the side to which the bearing cap is coupled, and the bearing cap. While closing the opening on the side opposite to the side where the The sealing member is inserted into the cylinder through the opening on the side where the sealing cap is connected to seal the opening, and in this state, the processing liquid is caused to flow through the passage in the cylinder formed by the flow path forming member. The inner surface of the cylinder is surface-treated.

[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 pretreated and the amount of the processing liquid carried out is increased. It does not cause harmful effects such as. Therefore, in engine manufacturing, after co-processing, the process moves to the step of plating with the combined body of the cylinder block and the bearing cap as it is, and the inner peripheral surface of the cylinder of the cylinder block is treated and this step is performed. It is possible to wash the combined body integrally in the treatment liquid washing work described above to wash off 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 diagram schematically showing an engine manufacturing process to which the method for plating an inner peripheral surface of an engine cylinder according to the present invention is applied. In the engine manufacturing process shown in this figure, first, the main part of the engine is manufactured by casting (casting process A). The main part of the engine is a cylinder block 1 and a cylinder block 1 in which a cylinder component part having four cylinders 1a arranged in parallel and a skirt-shaped crankcase part are integrally formed.
The bearing cap 2 attached to the crankcase portion of the above is manufactured separately in the casting process A and transferred to the processing process B.

In the processing step B, the cylinder block 1
The bearing cap 2 and the bearing cap 2 are machined, such as by drilling, so that the cylinder block 1 and the bearing cap 2 are provided with mounting holes for various parts and oil passages. After machining, the blind plug is press-fitted into the oil passage or the like of the cylinder block 1 as necessary (not shown).

After that, the cylinder block 1 and the bearing cap 2 are joined together, and the joined body 3 is processed into a crankshaft supporting portion and the like (co-processing step C). By co-processing the combined body 3 in this manner, the cylinder block 1 and the bearing cap 2 have a one-to-one correspondence relationship, so that the accuracy of the crankshaft supporting portion and the like is ensured. Has become.

When the co-processing step C is completed, the combined body 3 is next transferred to the surface treatment step D in order to plate 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, degreasing treatment, alkali etching treatment, mixed acid etching treatment, alumite treatment, plating treatment and drying treatment are performed in this order. Therefore, in the surface treatment step D, a treatment unit for performing each of these treatments is provided, and a water washing unit for washing off the treatment liquid and the like is provided between the treatment units. Cylinders 1 are transferred to each processing unit and washing unit in sequence.
The inner peripheral surface of a is plated.

In particular, in the surface treatment step D of the present embodiment, the processing in each processing section is carried out by an apparatus of a high-speed processing system, and the processing here will be described below using a plating processing section as an example. As described below.

2 and 3 schematically show the structure of the plating processing portion Da. In these figures, the plating treatment part D
Reference character a includes a plating apparatus body 10 and a sealing device 30.

A support block 12 as a cylinder block support portion is provided on a base 11 of the plating apparatus main body 10, and the combined body 3 is supported on the support block 12. Specifically, the support block 12
With the head side of the unit facing downward (in a state in which the head unit is turned upside down as compared with the state when mounted on a vehicle), the combined body 3 supports the support block 1
The support block 12 closes the lower opening of each cylinder 1a of the cylinder block 1 in this state.

A treatment liquid outlet passage 13 is formed in the support block 12 at a position below the combined body 3.
Further, on the upper surface of the support block 12, an opening 13a communicating with the processing liquid outlet passage 13 is provided at a position corresponding to each cylinder 1a of the cylinder block 1. Then, in the state where the combined body 3 is supported on the support block 12 as described above, the lower opening of each cylinder 1a and the opening 13a are aligned with each other.

Further, in the main body 10 of the plating apparatus, electrodes 14 also serving as flow path forming members are arranged at positions corresponding to the cylinders 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.
The pellet storage section 15 stores a large number of pellets 18 made of nickel as a soluble anode material. The electrode body is composed of an inner cylinder part 16 made of a metal pipe and an outer cylinder part 17 made of a porous metal plate or the like, and a pellet storage part 15 is formed between the inner and outer cylinder parts 16, 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 tubular portion 16.

The electrode 14 is attached to a holder 19 attached to the base 11 via a cylindrical attachment member 20, penetrates through the treatment liquid outlet passage 13 and protrudes upward from the opening 13a. . Then, with the combined body 3 supported on the support block 12 as described above,
The electrode 14 projects 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. As a result, inside each of the cylinders 1a, inside and outside of the electrode 14 (inside of the inner tubular portion 16), channels 21 and 22 that communicate with each other at the top via the cover 16a are formed, and the channel 22 on the outside is formed. Are communicated 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 treatment liquid introducing passage 23 communicating with the flow passage 21 inside the electrode 14 is formed in the internal space of the other members constituting the second electrode 2.

Although not shown, the plating apparatus main body 10 has a supply / discharge system for supplying a plating solution,
An electric system is provided for applying a voltage to the electrodes 14 and the like during processing. Briefly, in the plating solution supply / discharge system, the plating solution is sent from the plating solution storage tank to the processing solution introduction passage 23 via a pump, and the flow path 21,
After passing through 22, the processing liquid outlet passage 13 is configured to be recovered in the plating liquid storage tank via the plating liquid recovery pipe. Further, in the electric system, the electrode 14 is connected to the positive side of the power supply circuit, and the combined 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. It is configured so that a voltage is applied between 1 and 1.

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

The sealing device 30 includes each cylinder 1a.
Specifically, each member as a sealing jig that is inserted into an upper opening which is an opening on the side opposite to the support block 12 side is specifically described. The sealing device 30 includes the cylinder block 1 A movable plate 31 having 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 an operating means (not shown). Each mounting member 32 is provided with a hollow truncated cone-shaped seal member 33 made of an elastic material such as rubber at the lower end portion thereof, and a movable rod 34 integrally provided with a disk-shaped seal pressing member 34a at the lower end portion. Has been penetrated. The movable rod 34 has a structure in which it can be stroked in two steps by an air cylinder (not shown), whereby the seal pressing member 34a is moved stepwise to an ascending end position, an intermediate position and a descending end position. I'm supposed to get it. Then, when the seal pressing member 34a is at the rising end position, the compression force of the mounting member 32 and the seal pressing member 34a causes the seal member 33 to be in an expanded state in which it is expanded in an umbrella shape, while the seal pressing member 34a is When the seal member 33 is in the lower end position, the seal member 33 is in a diameter-reduced state in which it is closed by its own weight, and when the seal pressing member 53a is in an intermediate position, the seal member 33 is in a partially-expanded state.

In the processing in the plating processing unit Da, first, the sealing device 30 is operated in a state where the combined body 3 is placed on the support block 12, whereby each cylinder block 1 is operated. The opening of the cylinder 1a on the side opposite to the support block 12 side is sealed.

Specifically, when the movable plate 31 is lowered, the seal member 33 is inserted into each cylinder 1a through the through hole formed in the bearing cap 2 and the crankcase portion of the cylinder block 1. And is arranged immediately above the electrode 14. At this time, the seal pressing member 34a is held at the lower end position, so that the seal member 33 is in a reduced diameter state and narrowed to the 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 arranged in each cylinder 1a of the cylinder block 1, a seal pressing member 34 is provided.
Is raised to an intermediate position, so that the outer peripheral portion of each seal member 33 is in a semi-expanded state in which it does not contact 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 arranged immediately above, the seal pressing member 34a is raised to the rising end position, whereby the seal member 33 is completely spread as shown in FIG. In each cylinder 1a
The opening is sealed.

When the sealing of the cylinder 1a by the sealing device 30 is completed in this way, the plating liquid is supplied to the plating device main body 10 by operating the pump connected to the plating liquid storage tank (not shown). . As a result, the plating solution flows into the processing solution introduction passage 23,
High speed is achieved by applying a voltage between the electrode 14 and the cylinder block 1 while flowing out from the treatment liquid outlet passage 13 through 22 and flowing the plating liquid along the inner surface of the cylinder 1a which is the surface to be plated. Plating is performed.

In this case, since the upper opening of each cylinder 1a is sealed by the seal 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 can be satisfactorily performed in a state where the overflow is surely prevented.

The structure of the sealing device 30 is not limited to that described above, and for example, a sealing body that expands with air may be used.

The above is the description of the plating treatment section, but the same equipment as the plating treatment section Da is also used in the pretreatment section such as degreasing treatment, alkali etching treatment, mixed acid etching treatment and alumite treatment section. , Processing is performed at high speed. In this case, since the electrode 14 is not necessary in the other processing section, a cylindrical member substantially the same as the electrode 14 is attached to the support block 12 to form the flow path. Also,
In the pretreatment section, the sealing device may be simplified.

In the surface treatment step D, as described above, the water washing section is provided between the treatment sections to wash away the unnecessary treatment liquid adhering to the cylinder block 1. Then, by performing such cleaning on the entire combined body 3, it is possible to wash away both the unnecessary processing liquid adhering to the cylinder block 1 and the chips generated in the co-processing step C. It is

When the plating process for each cylinder 1a of the cylinder block 1 is completed in this way in the surface treatment step D, the combined body 3 is subjected to the honing finishing step E.
Then, honing finish processing is applied to the inner peripheral surface of each of the plated cylinders 1a. Specifically, the combined body 3 is placed on a predetermined workbench of a honing machine, the honing head is inserted into each cylinder 1a, and then the honing head is rotated to rotate the inner peripheral surface of the cylinder 1a. Are polished.

Combined body 3 which has been subjected to honing finish processing
Is transferred to a cleaning step F in order to wash away chips and the like generated in the honing finishing process, and is then decomposed into the cylinder block 1 and the bearing cap 2.

The disassembled cylinder block 1 and bearing cap 2 are transferred to the final assembly step G, in which various parts such as the crankshaft 4 are assembled and assembled again, whereby the engine is assembled. Complete.

As described above, according to the manufacture of the engine of the above embodiment, the combined body 3 which has been processed in the co-processing step C is directly transferred to the surface treatment step D, and this step D
Since the cylinder block 1 and the bearing cap 2 are integrally cleaned in the cleaning work performed in 1., it is not necessary to separately clean the bearing cap 2 after co-processing. Therefore, the washing process for the bearing cap alone can be reduced in the engine manufacturing process, and the engine can be manufactured more rationally.

By the way, in this way, the cylinder block 1
When the surface treatment step D is performed while the bearing cap 2 and the bearing cap 2 are integrated, there is concern that the bearing cap 2 may be unnecessarily pretreated, or the amount of the treatment liquid such as the plating liquid brought out may increase. However, in the surface treatment step D, as described above, the upper opening of each cylinder 1a, that is, the opening on the side where the bearing cap 2 is attached is sealed by the sealing device 30,
In this state, the treatment liquid is supplied only to the inner peripheral surface of each cylinder 1a to be treated, so that the treatment liquid adheres to the bearing cap 2 and unnecessary pretreatment is performed, or the amount of the treatment liquid taken out is reduced. There will be no adverse effects such as an increase.

Further, since the combined body 3 which has been processed in the co-processing step C can be transferred to the surface treatment step D as it is, the period for handling the cylinder block 1 and the bearing cap 2 after the co-processing separately is reduced. As a result of the co-processing, the cylinder block 1 and the bearing cap 2, which are in a one-to-one correspondence, are better prevented from being assembled incorrectly when they are assembled to other cylinder blocks or bearing caps. It becomes possible. In particular, in this embodiment, after co-processing the cylinder block 1 and the bearing cap 2 in the co-processing step C, the cylinder block 1 and the bearing cap 2 are always integrated, that is, the combined body 3 until the final assembly step G. Therefore, there is an advantage that erroneous assembly is surely prevented in the final assembly process G.

The above embodiment is a schematic description of an example of the manufacturing process of an engine to which the method for plating the inner peripheral surface of the cylinder of the engine according to the present invention is applied. Such work 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 to the inside of the cylinder of the cylinder block to perform the processing. Therefore, even if the process of plating the assembly of the cylinder block and the bearing cap as it is in the manufacturing of the engine is performed, the bearing cap is unnecessarily pretreated, and the amount of processing liquid taken out increases. It is possible to integrally wash the combined body in the treatment liquid washing operation performed in the step of applying the plating, without causing the above-mentioned adverse effect. Therefore, unlike the conventional case, there is no need to disassemble the combined body and wash the bearing cap by itself after co-processing, which allows the engine to be manufactured more rationally.

Moreover, since the cylinder block and the bearing cap, which are in a one-to-one correspondence, can be handled in a state in which they are joined together for a longer period of time after co-processing, it is possible to effectively prevent erroneous work during final assembly of the engine. You can

[Brief description of drawings]

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

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

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

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

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

[Explanation of symbols]

 1 Cylinder Block 1a Cylinder 2 Bearing Cap 3 Combined Body 4 Crank Shaft 10 Plating Machine Main Body 30 Sealing Device A Casting Process B Machining Process C Co-machining Process D Surface Treatment Process Da Plating Treatment Department E Honing Finishing Process F Cleaning Process G Final Assembly Process

Claims (1)

[Claims] 1. A method in which a cylinder block and a bearing cap are separately formed, and these are integrally joined to co-process a supporting portion for a crankshaft and the like, and then plating is performed on the cylinder inner peripheral surface 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 portion of the surface treatment section, and the flow path forming member protruding from the cylinder block support portion is attached to the bearing cap. Is formed into the cylinder of the cylinder block through an opening on the side opposite to the side on which the bearing cap is coupled to form a path for flowing the processing liquid inside the cylinder, and on the side opposite to the side on which the bearing cap is coupled. While the opening of is blocked by the cylinder block support, the bearing cap is connected The sealing member is inserted into the cylinder through the opening on the side to seal the opening, and in this state, the processing liquid is caused to flow through the passage in the cylinder formed by the flow path forming member to surface the inner surface of the cylinder. A method for plating an inner surface of a cylinder of an engine, characterized by performing a treatment.