JP3988503B2 - Cylinder block surface treatment equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  In this invention, the cylinder bore surface of the cylinder block is etched.TableThe present invention relates to a surface treatment apparatus used for surface treatment.
[0002]
[Prior art]
Conventionally, in a cylinder block of an engine made of a light metal such as aluminum (Al) or an alloy thereof, for example, in order to ensure wear resistance of a cylinder bore part on which a piston slides, a liner made of cast iron is usually provided on the cylinder bore part. It is manufactured by press-fitting or casting. The liner is disposed over a range covering at least the piston top dead center to the piston bottom dead center of the cylinder bore portion.
[0003]
However, when a cast iron liner is provided in the cylinder bore as described above, it is difficult to make full use of the excellent characteristics such as lightness and high thermal conductivity of the cylinder block base material (light metal such as Al alloy). There is.
In recent years, in response to an increasing demand for further downsizing of an engine, a reduction in the pitch between bores is also required for the cylinder block.
[0004]
For this reason, it is considered to eliminate the cast iron liner and secure the wear resistance of the cylinder bore part by another method. As one of such methods, a porous preform (preliminary molded body) having a predetermined volume ratio that is higher in hardness than the base material of the cylinder block is provided in the cylinder bore portion, and the cylinder block base material is impregnated during casting. There is a method of combining them (see, for example, JP-A-2001-71117). As such a porous preform, a sintered metal preform obtained by sintering metal powder, or a preform made of fiber reinforcement based on reinforcing fibers can be applied.
[0005]
As another method, a method of forming a dispersion-strengthened Al alloy in which the material of the cylinder block base material such as an Al alloy is strengthened by increasing the Si content and dispersing primary crystal Si is also considered. In the case of the porous preform, the structure is a so-called three-dimensional network structure (network structure), and the mesh-shaped voids are impregnated with the melt of the cylinder block base material. The property becomes better.
When the above method is adopted, the wear resistance of the piston sliding portion can be secured while maintaining the excellent characteristics such as the light weight and high thermal conductivity of the cylinder block base material (for example, Al alloy). It is also possible to reduce the pitch between the bores by eliminating the liner, and it is also possible to increase the displacement based on the existing engine by eliminating the liner. Moreover, there is an advantage that the conventional casting method can be applied as it is.
[0006]
In such a cylinder block with improved wear resistance on the cylinder bore surface, honing or etching is considered to be performed on the cylinder bore surface for the purpose of improving oil retention while maintaining wear resistance. (For example, see JP-A-6-167242 or JP-A-2000-354913).
[0007]
By performing honing or etching on the cylinder bore surface in this way, the reinforcing material portion is protruded by a predetermined amount from the base material matrix, and the matrix itself has a so-called satin finish in which numerous fine irregularities exist. Many fine oil reservoirs can be formed. As a result, while maintaining the wear resistance, it is possible to improve the oil retention and to secure the scuff resistance (burn-in).
[0008]
[Problems to be solved by the invention]
By the way, the piston that reciprocates in the cylinder bore changes the direction of sliding movement between the top dead center and the bottom dead center of the reciprocating sliding stroke. Although it is exposed to severe use conditions, especially in the case of the top dead center, it becomes a particularly severe condition because of the explosive force of the engine combustion chamber, and the seizure problem becomes an important issue.
[0009]
As a countermeasure against the seizure of the top dead center, the roughness of the cylinder bore surface may be made rougher by honing or etching to improve the oil retention, but on the other hand, when the entire cylinder bore surface is roughened in this way Increases the wear of the mating member (piston), lowers the airtightness of the sliding part, or increases the oil consumption.
Therefore, for the piston top dead center and its vicinity where seizure is particularly likely to occur, it is necessary to roughen the cylinder bore surface to improve oil retention, but in other areas, that is, the bottom dead center side, the surface should be It is not preferable to make it too rough.
[0010]
Accordingly, an object of the present invention is to make it possible to adjust the roughness of the cylinder bore surface between the top dead center side and the bottom dead center side of the reciprocating sliding stroke of the piston when the surface treatment is performed on the cylinder bore surface of the cylinder block. It was made as.
[0016]

[Means for Solving the Problems]

  For this reason, Related to the present inventionRuThe surface treatment apparatus for the Linda block is based on a surface treatment apparatus that performs an etching process by bringing an etching solution into contact with the cylinder bore surface of the cylinder block, and a base having a base end surface that supports a mating surface with the cylinder head of the cylinder block; A columnar body having an outer diameter smaller than the inner diameter of the cylinder bore by a predetermined amount, and standing on the base end surface of the base; an etchant storage means for storing an etchant; and an elevation control for controlling the elevation of the storage means Means for supporting the mating surface of the etching solution storage means and the cylinder head of the cylinder block with the base end surface of the base, and with the columnar body inserted through the cylinder bore, It is characterized by comprising a communication means for communicating with a gap formed between the outer surface of the columnar body. .
[0017]
  MaTheRelated to the present inventionOtherThe cylinder block surface treatment apparatus is based on a surface treatment apparatus that performs an etching process by bringing an etching solution into contact with the cylinder bore surface of the cylinder block, and has a base end surface that supports a mating surface with the cylinder head of the cylinder block A columnar body having an outer diameter dimension that is a predetermined amount smaller than the inner diameter dimension of the cylinder bore, fitted into an insertion hole provided in the base, and provided so as to protrude and retract with respect to the base end surface; and the columnar body Elevating control means for controlling the elevating and lowering.
  Then, with the columnar body in the lowered position, the etching solution is stored in a recess formed by the upper end surface of the columnar body and the inner peripheral surface of the insertion hole, and is aligned with the cylinder head of the cylinder block. With the surface supported by the base end surface of the base, the columnar body is raised and inserted into the cylinder bore, thereby supplying an etching solution to the gap formed between the cylinder bore surface and the outer surface of the columnar body. Thus, the surface of the cylinder bore is etched.
[0018]
In this case, more preferably, the columnar body is provided with an etchant supply / discharge path that opens to the upper end surface of the columnar body, and an etchant supply / discharge control unit that controls supply / discharge of the etchant is connected to the etchant supply / discharge path. Has been.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
  Prior to the description of the embodiment,First, RealForm of applicationReference exampleWill be described.
  FIG. 3 illustrates the present invention.The fruitForm of applicationReference exampleIt is a section explanatory view showing a schematic structure of a surface treatment device of a cylinder block of an engine concerning. As shown in this figure, the cylinder block W according to the present embodiment is set on the base 11 of the etching processing apparatus 10 with its top and bottom reversed.
  The cylinder block W is used, for example, in an automobile engine, and a lower end surface of a cylinder head (not shown) is placed on a top deck Wf of the cylinder block W (an upper end surface when mounted on a vehicle) via a predetermined gasket material. And fastened in close contact. That is, the top deck Wf of the cylinder block W forms a mating surface with the cylinder head.
[0020]
A piston (not shown) is inserted into the cylinder bore B of the cylinder block W so as to be slidable in the vertical direction. The piston slides in the cylinder bore B over a range from the top dead center Pu to the bottom dead center Pb. On both sides of the cylinder bore B, there are formed water jackets J through which cooling water flows so as to substantially follow the inner wall surface of the cylinder bore B between the cylinder block outer wall portions spaced apart from the cylinder bore inner wall surface.
[0021]
The cylinder block W uses a light alloy (for example, aluminum alloy) material, and after obtaining a casting material by applying, for example, a die-casting method, the piston sliding surface or cylinder of the cylinder bore B is applied to the casting material. A required portion such as a mating surface Wf with a head (not shown) is finished and obtained as a final product.
[0022]
  BookReference exampleMore preferably, the cylinder bore portion B has a hardness higher than that of the base material (aluminum alloy) of the cylinder block W for the purpose of ensuring the wear resistance of the inner peripheral surface (piston sliding surface) of the cylinder bore B. A porous preform (preliminary molded body: not shown) having a high predetermined volume ratio is disposed.
  That is, the cylinder bore portion B sets the porous preform in a portion corresponding to the cylinder bore portion B of the casting mold, and then injects a molten metal as a base material into the casting cavity and impregnates the preform with the molten metal. It is formed by.
[0023]
The porous preform is configured, for example, as a sintered metal preform obtained by sintering metal powder, and the metal powder is, for example, Fe (iron) -Cr (chromium) -Ni (nickel) type Was used.
In addition to the above, the porous preform having a predetermined volume ratio that is higher in hardness than the base material (aluminum alloy) of the cylinder block W is made of, for example, a fiber reinforcing material based on reinforcing fibers. Can also be used.
[0024]
  BookReference exampleThen, the surface of the cylinder bore portion B with improved wear resistance is subjected to an etching process for the purpose of improving oil retention while maintaining wear resistance. By performing such an etching process, the reinforcing material portion is protruded by a predetermined amount from the matrix of the base material, and the matrix itself has a number of fine irregularities, so-called satin-like, and many fine oil reservoirs are formed. be able to. As a result, while maintaining the wear resistance, it is possible to enhance the oil retention and to secure the scuff resistance (burn-in).
[0025]
  Hereinafter, this etching process will be described.
  BookReference exampleAs shown in FIG. 3, the surface treatment (etching) apparatus 10 according to FIG. 3 includes a base 11 having a base end surface 11 g that supports a mating surface Wf with a cylinder head of the cylinder block W, and a cylinder bore of the cylinder block W. On the base end face 11g of the base 11 having an outer diameter smaller than the inner diameter of B by a predetermined amount.StandingAnd a columnar columnar body 13 provided.
[0026]
The columnar body 13 includes a liquid passage 11a (etching solution supply path) that passes through the center of the base 11 and opens to the outer peripheral surface in the vicinity of the base end surface 11g, and a base that extends along the outer surface of the columnar body 13. An annular groove 11c formed by digging the base 11 and a liquid passage 11b (etching liquid discharge passage) that opens on the outer surface of the base 11 and communicates with the annular groove 11c are provided.
[0027]
An etching liquid supply pipe 15 having an upstream end communicating with an etching liquid supply source (tank: not shown) and a valve (supply valve) Vs interposed in the middle is connected to the etching liquid supply path 11a. Yes. Further, an etchant discharge pipe 17 having a downstream end communicating with an etchant discharge tank (not shown) and a valve (supply valve) Vd interposed in the middle is connected to the etchant discharge path 11b. .
These etching solution supply tank (not shown), supply pipe 15, supply valve Vs, supply path 11a, discharge path 11b, discharge pipe 17, discharge valve Vd and discharge tank (not shown) are the main parts of the columnar body 13. “Etching liquid supply / discharge means” is configured to supply and discharge the etching liquid to and from the outer surface near the base end face 11g.
[0028]
Both the supply valve Vs and the discharge valve Vd are preferably constituted by electromagnetic control valves, and are connected to a control unit (not shown) of the processing apparatus 10 so as to be able to send and receive signals. Control signals from the control unit Accordingly, the opening / closing state, the valve opening degree, or the opening / closing speed is controlled, whereby the operating state of the “etching solution supply / discharge means” is controlled.
[0029]
When performing the etching process on the surface of the cylinder bore B of the cylinder block W using the processing apparatus 10 having the above configuration, the cylinder block W is turned upside down and the mating surface Wf with the cylinder head is set to the base 11. The base end face 11g is supported, and the columnar body 13 is set in a state of being inserted into the cylinder bore B. In this set state, a gap S1 communicating with the annular groove 11c is formed between the surface of the cylinder bore B and the outer surface of the columnar body 13. In this set state, the piston top dead center Pu of the cylinder bore B is positioned on the lower side, and the bottom dead center Pb is positioned on the upper side.
[0030]
  Then, by opening the supply valve Vs with the discharge valve Vd closed, the etching solution E is supplied to the gap S1 from below (that is, from the top dead center Pu side). As a result, the etching liquid E comes into contact with the surface of the cylinder bore B, and the etching process is performed.
  BookReference exampleThen, as the etching solution E, for example, a 10% concentration sodium hydroxide (NaOH) solution was used. Instead of this, various other solutions can be used as the etching solution as long as they can corrode the material constituting the surface portion of the cylinder bore B, such as a potassium hydroxide (KOH) solution.
[0031]
FIG. 1 shows an example in which a sodium hydroxide solution having a concentration of 5% or 10% is used as an etching solution. The etching time (the time during which the surface to be processed is in contact with the etching solution) and the surface to be processed are It is the graph which showed the relationship with the reinforcement protrusion amount (micrometer).
The amount of protrusion of the reinforcing material on the surface to be processed indicates the amount of protrusion (height) of the reinforcing material from the reference surface of the surface to be processed in which the reinforcing material is dispersed. As can be seen from the graph of FIG. The amount of protrusion of the reinforcing material on the surface to be processed increases in proportion to the etching time. In general, it is known that the larger the amount of reinforcement protrusion, the rougher the surface roughness. Therefore, it can be understood that the etching time may be increased in order to improve the oil retention of the surface to be processed by performing the surface treatment.
[0032]
  So bookReference exampleThen, when surface treatment is performed on the surface of the cylinder bore B, in order to adjust the surface roughness between the top dead center Pu side and the bottom dead center Pb side of the reciprocating sliding stroke of the piston, the top dead center Pu and its vicinity are adjusted. And the bottom dead center Pb and the vicinity thereof were made to have different etching states.
[0033]
That is, by performing the etching process using the processing apparatus shown in FIG. 3, the surface of the cylinder bore B of the cylinder block W is etched with the top dead center Pu positioned below the bottom dead center Pb. Then, since the etching liquid E is supplied from the top dead center Pu side and discharged from the top dead center Pu side, the top dead center Pu and the vicinity thereof are easier and more reliable than the bottom dead center Pb and the vicinity thereof. The contact time in contact with the etching solution can be increased.
[0034]
In this way, the etching process is performed on a predetermined region including the range from the piston top dead center Pu to the piston bottom dead center Pb on the surface of the cylinder bore B, and the top dead center Pu and its vicinity and the bottom dead center Pb and the vicinity thereof are By making the etching state different, the surface roughness of the cylinder bore B can be adjusted between the top dead center Pu side and the bottom dead center Pb side of the reciprocating sliding stroke of the piston. And the bottom dead center Pb side can satisfy different requirements for the surface roughness of the cylinder bore B (and therefore the oil retention).
In particular, the top dead center Pu and the vicinity thereof and the bottom dead center Pb and the vicinity thereof are made different by making the contact time in contact with the etching solution different between the top dead center Pu and the vicinity thereof and the bottom dead center Pb and the vicinity thereof. Thus, the etching state can be surely changed according to the difference in the contact time.
[0035]
Specifically, the top dead center Pu and the vicinity thereof have a longer contact time with the etching solution E than the bottom dead center Pb and the vicinity thereof. The surface roughness is increased compared to the bottom dead center Pb side, and on the bottom dead center Pb side, it is possible to prevent an increase in wear of the mating member (piston), a decrease in airtightness of the sliding portion, or an increase in oil consumption. In addition, at the top dead center Pu where the seizure is particularly likely to occur and in the vicinity thereof, the surface of the cylinder bore B can be made rougher to improve the oil retention.
[0036]
FIG. 2 is a graph showing various control pattern examples of the etching liquid level when the surface of the cylinder bore B is etched using the surface treatment apparatus 10. In the graph of FIG. 2, the liquid level height “0” corresponds to the position of the top dead center Pu of the cylinder bore B, and the liquid level height H3 corresponds to the position of the bottom dead center Pb.
The pattern Y1 (broken line) feeds / discharges the etchant E as usual. In this case, the contact time with the etchant E on the top dead center Pu side is T7, and the bottom dead center Pb The contact time on the side is (T6-T1).
[0037]
Both the patterns Y2 and Y3 are obtained by reducing the supply rate and discharge rate of the etching solution (that is, reducing the rising / lowering rate of the liquid level). In these cases, the contact with the etching solution E on the top dead center Pu side is performed. The time is T7, the contact time on the bottom dead center Pb side is (T3-T2), and the difference in contact time between the top dead center Pu side and the bottom dead center Pb side is large. That is, it is possible to easily and surely make the contact time at which the top dead center Pu and the vicinity thereof are in contact with the etching solution E longer than the bottom dead center Pb and the vicinity thereof.
In particular, in the case of the pattern Y3, the discharge speed is changed so as to be further reduced during the etching liquid discharge process (at time T4), and the top dead center is higher than that of the cylinder bore surface corresponding to the liquid level height H2. For the portion close to Pu, the contact time with the etching solution E can be made longer.
[0038]
The pattern Y4 is set so that the liquid level remains stationary for a predetermined time (from time T5 to the vicinity of time T7) during the etching liquid discharge process. In this case, the cylinder bore surface corresponding to the liquid level height H1 For the portion closer to the top dead center Pu than the contact time with the etching solution E, the contact time with the etching solution E can be made very long. It can be made even longer.
Note that such a liquid level stationary step may be provided in the middle of the etching liquid supply process.
[0039]
  In particular, the bookReference exampleThen, the cylinder block W is configured by impregnating a porous preform with molten cylinder block base material at a predetermined depth from the surface of at least the predetermined region of the surface of the cylinder bore B. The wear resistance of the cylinder bore surface can be reliably improved, and the oil retention can be improved while maintaining the wear resistance by performing etching treatment on the surface.
[0040]
  Also bookReference exampleThen, by using the processing device 10, the mating surface Wf of the cylinder block W with the cylinder head is supported by the base end surface 11g of the base 11, and the columnar body 13 erected on the base end surface 11g is provided. With the etching liquid supply / discharge means for supplying and discharging the etching liquid E to and from the outer surface side of the columnar body B in the vicinity of the base end face 11g while being inserted into the cylinder bore B, the surface of the cylinder bore B and the outer surface of the columnar body 13 are separated. An etching solution E is supplied to the gap S1 formed therebetween, and the surface of the cylinder bore B is etched.
[0041]
Therefore, the cylinder block W is etched in a state where the top dead center Pu is located below the bottom dead center Pb, and the etching solution E is supplied from the top dead center Pu side and discharged from the top dead center Pu side. Thus, it is possible to easily and reliably set the contact time at which the top dead center Pu and the vicinity thereof are in contact with the etching solution E to be longer than the bottom dead center Pd side.
[0042]
  Next, the first of the present invention1The embodiment will be described. In the following description, the aboveReference exampleThose having the same configuration as in the case of and having the same function are denoted by the same reference numerals, and further description thereof is omitted.
  FIG.11 shows a schematic configuration of a surface treatment (etching treatment) apparatus 20 according to the embodiment. As shown in this figure, the surface treatment apparatus 20 includes a base 21 having a base end surface 21g for supporting a mating surface Wf with a cylinder head of a cylinder block W, and an outer diameter smaller than the inner diameter of the cylinder bore B by a predetermined amount. A columnar body 23 having a size and standing on the base end face 21g of the base 21 and an etching solution storage tank Tk for storing the etching solution E are provided.
[0043]
Although not specifically shown, the storage tank Tk is provided with elevating means constituted by, for example, a known lifter device, and a controller for controlling the elevating operation of the elevating means is provided. . The vertical position of the storage tank Tk can be arbitrarily adjusted by driving and controlling the lifting means (for example, a lifter device) in accordance with a control signal from the controller.
[0044]
The base 21 has an annular groove 21c formed by digging the base 21 along the outer surface of the columnar body 23, and a liquid passage 21a that opens to the outer surface of the base 21 and communicates with the annular groove 21c. Is provided. The liquid passage 21a is connected to a communication pipe 25 that communicates with the bottom of the storage tank Tk.
Accordingly, the annular groove 21c and the storage tank Tk are always in communication with each other through the liquid passage 21a and the communication pipe 25.
[0045]
  When performing the etching process on the surface of the cylinder bore B of the cylinder block W using the processing apparatus 20 having the above configuration,Reference example aboveIn the same manner as in the above, the cylinder block W is turned upside down so that the mating surface Wf with the cylinder head is supported by the base end surface 21g of the base 21 and the columnar body 23 is inserted into the cylinder bore B. . In this set state, a gap S2 communicating with the annular groove 21c is formed between the surface of the cylinder bore B and the outer surface of the columnar body 23. In this set state, the piston top dead center Pu of the cylinder bore B is positioned on the lower side, and the bottom dead center Pb is positioned on the upper side.
[0046]
The setting operation of the cylinder block W to the surface treatment apparatus 20 is performed in a state where the vertical position of the storage tank Tk is set so that the liquid level of the storage tank Tk is lower than the liquid passage 21g. Therefore, the etching liquid E does not flow into the gap S2 during setting.
[0047]
Then, after the set is completed, the storage tank Tk is moved up to raise the position of the liquid surface thereof, so that the etching liquid E is transferred from the storage tank Tk to the base 21 through the communication pipe 25 and the liquid passage 21a. The annular groove 21c is further introduced into the gap S2, and etching is performed.
At this time, since the gap S2 and the storage tank Tk communicate with each other, the liquid level in both is always maintained at the same level.
[0048]
  As described above, also in the present embodiment, the cylinder block W is etched with the top dead center Pu positioned below the bottom dead center Pb. In this case, since the liquid level of the etching liquid E is always maintained at the same level in the etching liquid storage tank Tk and the gap S2, the gap S2 can be easily and reliably controlled by raising and lowering the storage tank Tk. The liquid surface can be controlled, and the contact time at which the top dead center Pu and the vicinity thereof are in contact with the etching liquid E can be made longer than the bottom dead center Pb side. as a result,Reference example aboveAs in the case of, the top dead center Pu and its vicinity are roughened compared to the bottom dead center Pb side, and on the bottom dead center Pb side, the wear of the mating member (piston) increases and the sliding part In addition to preventing a decrease in airtightness or an increase in oil consumption, the surface of the cylinder bore B can be made rougher and the oil retention can be improved at the top dead center Pu and its vicinity where seizure is particularly likely to occur. It is.
[0049]
  Next, the first of the present invention2The embodiment will be described.
  FIG.2The schematic structure of the surface treatment (etching process) apparatus 30 according to the embodiment is shown, and FIG. 6 shows an enlarged main part thereof. As shown in these drawings, the surface treatment apparatus 30 includes a base 31 having a base end surface 31g for supporting a mating surface Wf with a cylinder head of the cylinder block W, and an outer diameter smaller than the inner diameter of the cylinder bore B by a predetermined amount. A columnar body 33 having a diameter and fitted in an insertion hole 31f provided in the base 31 so as to be able to protrude and retract with respect to the base end face 31g is provided.
[0050]
Although not specifically shown, the columnar body 33 is provided with a drive device for raising and lowering the columnar body 33 and a controller for controlling the operation of the device. The vertical position of the columnar body 33 can be arbitrarily adjusted by controlling the driving device in accordance with a control signal from the controller.
[0051]
  When performing the etching process on the surface of the cylinder bore B of the cylinder block W using the surface treatment apparatus 30 having the above configuration, first, the columnar body 33 is in the lowered position (see FIG. 5). The etching solution E is stored in a recess 31d formed by the upper end surface of the columnar body 33 and the inner peripheral surface of the insertion hole 31f.
  And aboveReference example and firstAs in the case of the embodiment, the cylinder block W is turned upside down and the mating surface Wf with the cylinder head is set to be supported by the base end surface 31 g of the base 31. In this set state, the piston top dead center Pu of the cylinder bore B is positioned on the lower side, and the bottom dead center Pb is positioned on the upper side.
[0052]
After setting in this way, the columnar body 33 is lifted and inserted into the cylinder bore B, whereby the etching solution E stored in the recess 31d is pushed up into the cylinder bore B, and the cylinder bore B The etching solution E is supplied to the gap S3 formed between the surface and the outer surface of the columnar body 33, and the surface of the cylinder bore B is subjected to an etching process.
[0053]
As described above, also in the present embodiment, the cylinder block W is etched with the top dead center Pu positioned below the bottom dead center Pb. In this case, by controlling the vertical movement of the columnar body 33, the etching liquid surface of the gap S3 can be controlled easily and reliably, and the etching liquid on the top dead center Pb side is lower than the bottom dead center Pu and the vicinity thereof. The contact time for contacting E can be lengthened.
[0054]
  Next, the above2A modification of the embodiment will be described.
  FIG.2The schematic structure of the surface treatment (etching process) apparatus 40 which concerns on the modification of embodiment of this invention is shown, and FIG. 8 has expanded and shown the principal part. As shown in these drawings, in the surface treatment apparatus 40, the columnar body 43 is fitted into the columnar body 43 that is fitted in the insertion hole 41f provided in the base 41 and can be projected and retracted with respect to the base end surface 41g. An etching solution supply / discharge path 44 is provided in the upper end surface 43f of the substrate.
[0055]
The supply / discharge path 44 communicates with the switching valve Vc via the liquid pipe 45. A supply pipe 46 and a discharge pipe 47 for the etching liquid E are connected to the switching valve Vc, and the liquid pipe 45 is closed and the supply pipe 46 / discharge pipe 47 is controlled by switching the internal passage of the switching valve Vc. The connection to either of these can be switched. In a normal time, such as during an etching process, the switching valve Vc is maintained at a switching position where the liquid pipe 45 is closed.
[0056]
When the etching process is repeated many times and deterioration of the etching solution E is recognized, the switching valve Vc is switched so that the liquid pipe 45 and the discharge pipe 47 communicate with each other. The used etching solution E is discharged. The upper end surface 43f of the columnar body 43 is inclined so as to fall toward the center where the supply / discharge passage 44 is opened so that old liquid does not remain when the etching liquid E is replaced.
[0057]
Thereafter, the switching valve Vc is switched so that the liquid pipe 45 and the supply pipe 46 communicate with each other, and an unused new etching liquid E is supplied into the recess 41d.
Thus, according to this modification, when the etching solution E stored in the recess 41d formed by the upper end surface 43f of the columnar body 43 and the inner peripheral surface of the insertion hole 41f of the base 41 deteriorates. Can be easily replaced with a new liquid.
[0058]
  The aboveReference examples andEach embodiment is for a cylinder block W using a porous preform to improve the wear resistance of the cylinder bore B. Instead, a dispersion strengthened type in which a reinforcing material is dispersed in a matrix. For example, the present invention may be applied to a cylinder block made of an Al alloy in which primary alloy Si as a reinforcing material is dispersed in an Al matrix.
  Thus, it goes without saying that the present invention is not limited to the above-described embodiments, and various modifications, improvements, and design changes can be made without departing from the scope of the invention.
[0067]

【The invention's effect】

Related to the present inventionRuAccording to the surface treatment apparatus for the Linda block, the mating surface of the cylinder block with the cylinder head is supported by the base end surface of the base, and the columnar body erected on the base end surface is inserted through the cylinder bore. The cylinder block has a top dead center at the bottom dead center because there is a communication means for communicating the gap formed between the cylinder bore surface and the outer surface of the columnar body and the etchant storage means for storing the etchant. Etching is performed in a state of being located below. In this case, since the liquid level of the etching liquid is always maintained at the same level in the etching liquid storage means and the gap portion, the above-mentioned etching liquid storage means is controlled to be moved up and down by the lift control means, thereby easily and reliably The liquid level of the gap can be controlled, and the contact time at which the top dead center and the vicinity thereof are in contact with the etching solution can be made longer than the bottom dead center and the vicinity thereof. As a result, the top dead center and its vicinity are roughened compared to the bottom dead center side. On the bottom dead center side, the wear of the mating member (piston) increases, the airtightness of the sliding part decreases, or the oil consumption In addition to preventing an increase in the amount, the oil retaining property can be improved by making the cylinder bore surface rougher at and near the top dead center where seizure is particularly likely to occur.
[0068]
  MaTheRelated to the present inventionOtherAccording to the cylinder block surface treatment apparatus, the columnar body erected on the base end surface of the base is formed by the upper end surface of the columnar body and the inner peripheral surface of the insertion hole of the base in the state where it is in the lowered position. The cylinder bore surface by storing the etching solution in the recessed portion and raising the columnar body through the cylinder bore with the mating surface of the cylinder block and the cylinder head supported by the base end surface of the base. Since the etching solution is supplied to the gap formed between the cylindrical body and the outer surface of the columnar body, the cylinder block is etched with the top dead center positioned below the bottom dead center. In this case, by controlling the vertical movement of the columnar body by the vertical control means, the etching liquid level in the gap can be controlled easily and reliably, and the top dead center and the vicinity thereof are etched more than the bottom dead center and the vicinity thereof. The contact time in contact with the liquid can be lengthened. As a result, the top dead center and its vicinity are roughened compared to the bottom dead center side. On the bottom dead center side, the wear of the mating member (piston) increases, the airtightness of the sliding part decreases, or the oil consumption In addition to preventing an increase in the amount, at the top dead center and its vicinity where seizure is particularly likely to occur, the cylinder bore surface can be made rougher to improve the oil retention.
[0069]
In this case, more preferably, the columnar body is provided with an etchant supply / discharge path that opens to the upper end surface of the columnar body, and an etchant supply / discharge control unit that controls supply / discharge of the etchant is connected to the etchant supply / discharge path. Therefore, if the etching solution stored in the recess formed by the upper end surface of the columnar body and the inner peripheral surface of the insertion hole of the base deteriorates, it is easily replaced with a new solution. be able to.
[Brief description of the drawings]
FIG. 1 is a graph showing the relationship between etching time and amount of protrusion of reinforcing material on a surface to be processed.
FIG. 2 is a graph showing a liquid level control pattern of an etching process.
FIG. 3The fruitForm of applicationReference exampleIt is a section explanatory view showing a schematic structure of a surface treatment apparatus of a cylinder block concerning.
FIG. 4 shows the first of the present invention.1It is a section explanatory view showing a schematic structure of a surface treatment apparatus of a cylinder block concerning an embodiment.
FIG. 5 shows the first of the present invention.2It is a section explanatory view showing a schematic structure of a surface treatment apparatus of a cylinder block concerning an embodiment.
6 is an explanatory cross-sectional view showing an enlarged main part of the surface treatment apparatus of FIG. 5;
FIG. 7 shows the first of the present invention.2It is sectional explanatory drawing which shows schematic structure of the surface treatment apparatus of the cylinder block which concerns on the modification of this embodiment.
8 is an explanatory cross-sectional view showing an enlarged main part of the surface treatment apparatus of FIG.
[Explanation of symbols]
20, 30, 40 ... Surface treatment equipment
21, 31, 41 ... base
21g, 31g, 41g ... Base end face
23, 33, 43 ... Columnar body
46 ... Etching solution supply pipe
47 ... Etch solution discharge pipe
  21a ... Liquid passage
  25 ... Communication pipe
  31d, 41d ... recess
  31f, 41f ... insertion hole
  44 ... Etch solution supply / discharge path
  45 ... Liquid piping
  B ... Cylinder bore
  E ... Etching solution
  Pu ... Top dead center
  Pb ... Bottom dead center
S2, S3, S4 ... gap
  Tk ... Etching solution storage tank
  Vc: switching valve
W ... Cylinder block
  Wf: Cylinder block mating surface with cylinder head

Claims (3)

A surface treatment apparatus for performing an etching process by bringing an etching solution into contact with a cylinder bore surface of a cylinder block,
A base having a base end surface for supporting a mating surface with the cylinder head of the cylinder block;
A columnar body that has an outer diameter dimension that is smaller than the inner diameter dimension of the cylinder bore by a predetermined amount, and is erected on the base end surface of the base;
Etching solution storage means for storing the etching solution;
Elevating control means for elevating and controlling the storage means;
The cylinder bore surface and the columnar body in a state where the mating surface of the etching solution storage means and the cylinder head of the cylinder block is supported by the base end surface of the base and the columnar body is inserted into the cylinder bore. Communication means for communicating with a gap formed between the outer surface of
A cylinder block surface treatment apparatus comprising: A surface treatment apparatus for performing an etching process by bringing an etching solution into contact with a cylinder bore surface of a cylinder block,
A base having a base end surface for supporting a mating surface with the cylinder head of the cylinder block;
A columnar body having an outer diameter dimension that is smaller than the inner diameter dimension of the cylinder bore by a predetermined amount, fitted into an insertion hole provided in the base, and provided so as to protrude and retract with respect to the base end surface;
Elevating control means for elevating and controlling the columnar body;
And storing the etching solution in a recess formed by the upper end surface of the columnar body and the inner peripheral surface of the insertion hole in a state where the columnar body is in the lowered position, and a cylinder head of the cylinder block Is formed between the cylinder bore surface and the outer surface of the columnar body by raising the columnar body and inserting it into the cylinder bore in a state where the mating surface is supported by the base end surface of the base. A surface treatment apparatus for a cylinder block, wherein the etching solution is supplied to the part and the surface of the cylinder bore is subjected to an etching process. The columnar body is provided with an etchant supply / discharge path that opens to an upper end surface thereof, and an etchant supply / discharge control means that controls supply / discharge of the etchant is connected to the etchant supply / discharge path. The cylinder block surface treatment apparatus according to claim 2 .

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