JP2010046759A - Working method and working jig for cylinder block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working method of a cylinder block which can apply such a deformation as to cancel the deformation of a bore generated during an operation of an engine to the cylinder bore by a finishing work of the cylinder bore irrespective of unevenness in the form of a cylinder block and suppress the deterioration of a circularity of the cylinder bore during the operation of the engine. <P>SOLUTION: In the working method of the cylinder block, under a state that such a prescribed deformation as to make the cylinder bore 4 non-circular is applied to the cylinder bore 4, the finishing work for obtaining a prescribed circularity is applied to the cylinder bore 4. A deformation load as a load for applying the prescribed deformation to the cylinder bore 4 is applied to the cylinder block 1. For a displacement of a bore wall surface 4a in the radial direction of the bore, a feed back control is carried out which is based on a difference obtained by comparing a target value previously set in accordance with the prescribed deformation with a detected value obtained by detecting the displacement to control an adjustment amount of the level of the deformation load. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a machining method and a machining jig for a cylinder block constituting an internal combustion engine such as an automobile engine.

  For example, a cylinder block constituting an internal combustion engine (engine) such as an automobile engine has a number of cylinder bores corresponding to the number of cylinders of the engine. The cylinder bore is a cylindrical hole that slidably houses the piston. A cylinder head is attached to the cylinder block. The cylinder head is attached to the surface where the cylinder bore opens with respect to the cylinder block. Fasteners (head bolts) such as bolts are used to attach the cylinder head to the cylinder block. That is, the cylinder head is fastened and fixed to the cylinder block by screwing the head bolt into the bolt hole that penetrates the cylinder head and opens on the surface to which the cylinder head is attached. Here, the bolt hole into which the head bolt is screwed is generally provided around the cylinder bore.

  The cylinder bore that houses the piston is required to have a certain degree of roundness during actual operation of the engine. That is, when the roundness of the cylinder bore decreases during actual operation of the engine, the friction (sliding resistance) increases as the piston slides in the cylinder bore. The increase in friction causes the engine output to be limited and the fuel consumption to deteriorate. In addition, a decrease in the roundness of the cylinder bore causes a piston hitting sound.

  On the other hand, the cylinder bore is subjected to a finishing process such as a honing process in order to obtain a predetermined roundness. However, the cylinder bore is deformed to reduce the roundness (hereinafter referred to as “bore deformation”) when the cylinder head is attached to the cylinder block or the engine is in an actual working state. That is, the cause of the bore deformation includes the tightening force by the head bolt accompanying the mounting of the cylinder head and the thermal load during engine operation.

  Therefore, conventionally, when finishing a cylinder bore such as a honing process, a technique has been used in which a bore deformation that occurs when the cylinder head is attached or when the engine is actually operated is given in advance. In other words, cylinder bore finishing is performed in a state where bore deformation is reproduced, for example, by applying a load to the cylinder block at a predetermined position or direction. According to this method, a predetermined roundness is ensured in the state where the bore deformation is reproduced with respect to the cylinder block, and therefore, in the state where the load for reproducing the bore deformation is released, Is given a deformation in the opposite direction (which cancels the bore deformation) (hereinafter referred to as “reverse deformation”). As a result, the bore deformation that occurs when the cylinder head is mounted is canceled and suppressed.

  As described above, a machining method using a dummy head is known as a machining method that gives reverse deformation during the finishing of a cylinder bore (see, for example, Patent Document 1). The dummy head is a processing jig different from the cylinder head assembled as an actual product, and is attached to the cylinder block by a head bolt in the same manner as the cylinder head when processing the cylinder bore. The dummy head simulates the state in which the cylinder head is attached to the cylinder block.

  That is, when the dummy head is attached to the cylinder block, a prescribed tightening force corresponding to the tightening force associated with the attachment of the cylinder head is applied to the cylinder block, and the bore deformation occurs. In this state, the cylinder bore is finished, and then the dummy head is removed, so that the cylinder bore is reversely deformed by the restoring action accompanying the release of the tightening force. Then, by attaching the cylinder head to the cylinder block in which the cylinder bore is reversely deformed, the bore deformation caused by the tightening force by the head bolt is canceled and suppressed by the reverse deformation.

  Moreover, as a processing method which gives a reverse deformation to a cylinder block, there exists a processing method as disclosed in Patent Document 2, for example. In the processing method of Patent Document 2, a configuration having a pressing body supported by a hydraulic cylinder is used as a means for applying a load to the cylinder block. A load for reverse deformation is applied to a position corresponding to the bolt hole for the head bolt in a direction in which the cylinder block is sandwiched from the opposite side walls.

  By the way, the shape of the cylinder block varies due to individual differences or the like. For this reason, as described above, there may be variations in the deformed shape given when the cylinder bore is finished. Such variation in the deformed shape causes a cylinder bore that does not have sufficient roundness during actual operation of the engine.

  Specifically, as an example of the variation in the shape of the cylinder block, there is a variation in the thickness of the cylinder portion, which is a cylindrical wall portion formed so as to surround the cylinder bore. That is, the thickness of the cylinder portion may differ for each cylinder block or for each cylinder bore in the same cylinder block. In such a case, depending on the same load applied to each cylinder block or each cylinder bore, the deformed shape of the cylinder bore may vary, and a cylinder bore that does not have sufficient roundness during actual operation of the engine may occur. is there.

In this regard, according to the conventional technology as described above, the load applied to the cylinder block is adjusted for each location by adjusting the clamping force of the dummy head or the pressing force by the hydraulic cylinder, etc. It is thought that it can cope with the variation in shape. However, since variations in the shape of the cylinder block exist in various forms, it is difficult to sufficiently cope with each case.
JP 2004-243514 A JP 2008-62308 A

  The present invention has been made in view of the above-described problems, and the problem to be solved arises when the engine is actually operated with respect to the cylinder bore by finishing the cylinder bore regardless of the variation in the shape of the cylinder block. It is an object of the present invention to provide a cylinder block machining method and a machining jig that can give a deformation that cancels the bore deformation and can suppress a decrease in the roundness of the cylinder bore during engine operation.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

  That is, according to the first aspect of the present invention, in a state where the cylinder bore which is a cylindrical hole portion in which the piston is slidably mounted is given a predetermined deformation in which the cylinder bore becomes a non-circular shape, the cylinder bore has a predetermined true shape. A cylinder block machining method for performing a finishing process for obtaining circularity, wherein a deformation load, which is a load for giving the predetermined deformation to the cylinder bore, is applied to the cylinder block, and the cylinder bore is Feedback control based on a difference between a target value set in advance according to the predetermined deformation and a detection value obtained by detecting the displacement amount with respect to the radial displacement amount of the cylinder bore of the wall surface to be formed Is performed to control the amount of adjustment of the magnitude of the deformation load.

  According to a second aspect of the present invention, in the cylinder block machining method according to the first aspect, the displacement amount detection means for detecting the displacement amount is supported by a piston member insertable into the cylinder bore, and the displacement amount detection is performed. When the displacement amount is detected by the means, in the process of inserting the piston member into the cylinder bore, cleaning liquid or air is applied to the wall surface from the position in the piston member in the insertion direction of the piston member relative to the displacement amount detection means. Is discharged.

  According to a third aspect of the present invention, in the cylinder block machining method according to the first or second aspect, the piston member is rotatably provided with the central axis direction of the cylinder bore as the rotation axis direction.

  According to a fourth aspect of the present invention, in the cylinder block machining method according to any one of the first to third aspects, the piston member may interfere with the cylinder block when the piston member is inserted into the cylinder bore. A relief shape part is provided to avoid it.

  In Claim 5, In the processing method of the cylinder block as described in any one of Claims 1-4, the said deformation | transformation load is a predetermined | prescribed site | part in the outer peripheral surface of the cylinder part which is a wall-shaped part which forms the said cylinder bore. A pressing member having a pressing portion that is connected so as to be separated from each other and that receives a wedge action in a direction in which the pressing portions are separated from each other, and engages the wedge surface A pressing member that has a wedge portion that provides the wedge action, and is provided so as to be biased in a direction in which the wedge action is applied to at least the pressing member by fluid pressure, and a direction in which the pressing member provides the wedge action And a fluid pressure chamber forming member that forms a fluid pressure chamber that causes fluid pressure to act on the pressing member, and is supplied to the fluid pressure chamber. By urging the pressing member in the direction in which the wedge action is applied by body pressure, the wedge member is caused to act by applying the wedge action to the pressing member in a posture in which the pressing direction against the predetermined part is included in the separating direction. The fluid pressure is a control target of the feedback control.

  According to a sixth aspect of the present invention, in the machining method for a cylinder block according to the fifth aspect, the finishing process includes a honing grindstone and moves the grindstone against the cylinder bore by moving with respect to the cylinder bore. A head portion and a guide portion that is a surface on which the cylinder bore is opened and that can be moved close to and away from a head attachment surface to which a cylinder head attached to the cylinder block is fixed, and guides the head portion. Is used, and the fluid pressure chamber is provided in the guide portion.

  The cylinder block machining method according to any one of claims 1 to 4, wherein the deformation load is a dummy head simulating a cylinder head attached to the cylinder block, and the cylinder bore is opened. In addition, the tightening force is obtained by fastening and fixing to a head mounting surface that is a surface to which the cylinder head is mounted, and the tightening force is a control target of the feedback control.

  According to claim 8, a predetermined roundness of the cylinder bore is provided in a state in which the cylinder bore, which is a cylindrical hole portion that slidably houses the piston, is subjected to a predetermined deformation in which the cylinder bore has a non-circular shape. A cylinder block processing jig for performing a finishing process for obtaining a deformation load, wherein a deformation load is applied to the cylinder block, which is a load for applying the predetermined deformation to the cylinder bore. Means, a deformation load adjusting means for adjusting the magnitude of the deformation load applied by the deformation load applying means, and a displacement amount detecting means for detecting a radial displacement amount of the cylinder bore of the wall surface forming the cylinder bore. The displacement amount is detected by a target value set in advance according to the predetermined deformation and the displacement amount detecting means. By performing feedback control based on the difference by comparison with the detection value obtained by the arithmetic control unit for controlling the adjustment amount of the magnitude of the deformation load by the deformation load adjusting means is one including a.

  In a ninth aspect of the present invention, in the processing jig for a cylinder block according to the eighth aspect, the displacement amount detecting means is supported by a piston member insertable into the cylinder bore, and the piston member is When the displacement amount is detected by the displacement amount detection means, in the process of inserting the piston member into the cylinder bore from the position in the piston member in the insertion direction of the piston member relative to the wall surface from the displacement amount detection means. It has a discharge passage for discharging cleaning liquid or air.

  A tenth aspect of the present invention is the cylinder block machining jig according to the eighth or ninth aspect, further comprising a rotation mechanism that allows the piston member to rotate about the central axis direction of the cylinder bore as a rotation axis direction. It is.

  The cylinder block machining jig according to any one of claims 8 to 10, wherein the piston member is a relief-shaped portion for avoiding interference with the cylinder block when inserted into the cylinder bore. It is what has.

  In Claim 12, In the jig for processing a cylinder block according to any one of Claims 8 to 11, the deformation load applying means includes pressing portions that are detachably connected to each other, and these pressing portions. A pressing member having a wedge surface that receives a wedge action in a direction in which they are separated from each other; and a wedge portion that engages with the wedge surface to provide the wedge action; and at least the wedge action with respect to the pressing member by fluid pressure A pressing member provided so as to be urged in a direction in which pressure is applied, and a fluid pressure that supports the pressing member so as to be movable in a predetermined sliding direction including a direction in which the wedge action is applied, and that causes fluid pressure to act on the pressing member. A fluid pressure chamber forming member that forms a chamber, and the fluid pressure chamber as a deformation load with respect to a predetermined portion on an outer peripheral surface of a cylinder portion that is a wall-shaped portion that forms the cylinder bore The pressing member is biased in the direction of applying the wedge action by the supplied fluid pressure, so that the pressing member in a posture in which the pressing direction with respect to the predetermined portion is included in the separating direction receives the wedge action. The deformation load adjusting means has a valve mechanism for adjusting supply of the fluid pressure to the fluid pressure chamber, and the calculation control means controls the fluid pressure. The control object of the feedback control.

  According to a thirteenth aspect of the present invention, in the processing tool for a cylinder block according to the twelfth aspect, the finishing process includes a honing grindstone and moves the grindstone with respect to the cylinder bore by moving with respect to the cylinder bore. A head portion to be actuated, and a guide portion which is provided on the surface where the cylinder bore is opened and which can be moved close to and away from a head mounting surface to which a cylinder head mounted on the cylinder block is fixed. The honing process is performed using the configuration provided, and the fluid pressure chamber forming member is a member configuring the guide portion.

  In Claim 14, In the jig for processing a cylinder block according to any one of Claims 8 to 11, the deformation load applying means is a dummy head simulating a cylinder head attached to the cylinder block; A fastening member for fastening and fixing the dummy head to a head mounting surface that is a surface on which the cylinder bore is opened and the cylinder head is mounted, and the fastening member is tightened as the deformation load The dummy head is subjected to a fastening force obtained by fastening and fixing the dummy head to the head mounting surface, and the deformation load adjusting means is configured to fix the fastening member when fastening the dummy head to the head mounting surface. A tightening mechanism for tightening, wherein the calculation control means applies the tightening force to the gripping force; The control target of Dobakku control is intended.

As effects of the present invention, the following effects can be obtained.
That is, according to the present invention, regardless of the variation in the shape of the cylinder block, the cylinder bore can be deformed so as to cancel the bore deformation that occurs during engine operation by finishing the cylinder bore. It is possible to suppress a decrease in the roundness of the.

  In the present invention, when finishing the cylinder bore of the cylinder block, the cylinder bore is deformed so as to cancel out the bore deformation that occurs during actual operation of the engine, and the cylinder bore is deformed into a non-round state, and the deformation amount is feedback controlled. To try to adjust. In other words, in the present invention, when finishing the cylinder bore, the amount of deformation of the cylinder bore is detected, and the load for applying deformation to the cylinder bore is adjusted so that the detected value becomes a predetermined target value. Embodiments of the present invention will be described below.

  A first embodiment of the present invention will be described. As shown in FIGS. 1 and 2, a cylinder block 1 to be processed in the present embodiment constitutes an engine mounted on an automobile or the like, and its main body is made of aluminum. The cylinder block 1 has a head mounting surface 3, a cylinder bore 4, a cylinder portion 5, and a water jacket 6.

  The cylinder block 1 of the present embodiment constitutes an in-line four-cylinder engine and has four cylinder bores 4 (see FIG. 2). The cylinder bore 4 is a cylindrical hole that slidably houses a piston (not shown). The four cylinder bores are arranged in a row in a state adjacent to each other so that the central axis directions are parallel to each other. As processing for the cylinder block 1, finishing processing for the cylinder bore 4 is performed.

  The head attachment surface 3 is a surface to which a cylinder head (not shown) is attached. The head mounting surface 3 is a sealing surface formed as a flat surface on one side of the cylinder block 1. A cylinder head is attached to the head attachment surface 3 via a gasket or the like. A head bolt is used to attach the cylinder head to the head attachment surface 3. That is, as shown in FIG. 2, the head bolt is screwed into the bolt hole 12 serving as a female screw portion that penetrates the cylinder head and opens to the head mounting surface 3, whereby the cylinder head is fastened to the cylinder block 1. Fixed.

  A bolt fastening portion 10 as a fastening portion used for fastening and fixing the cylinder head to the cylinder block 1, that is, a bolt hole 12 into which the head bolt is screwed, is provided around the cylinder bore 4 on the head mounting surface 3. In the present embodiment, as shown in FIG. 2, four bolt holes 12 are provided at substantially equal intervals around the cylinder bore 4. In addition, two bolt holes 12 are shared between adjacent cylinder bores 4. That is, in the cylinder block 1 constituting the in-line four-cylinder engine, a total of ten bolt holes 12 are provided for the four cylinder bores 4 arranged in a line.

  An oil pan (not shown) is attached to the cylinder block 1 on the side opposite to the head attachment surface 3. Hereinafter, in the cylinder block 1, the side on which the cylinder head is assembled (upper side in FIG. 1) is referred to as “upper”, and the opposite side (lower side in the same figure) is referred to as “lower”.

  Four cylinder bores 4 are arranged in a state where the center axis direction is the vertical direction and is aligned in a row as described above. A piston ring is mounted on the piston housed in the cylinder bore 4, and the piston reciprocates in the vertical direction in the cylinder bore 4 through the piston ring.

  The space above each piston in each cylinder bore 4 constitutes a part of a combustion chamber for burning a fuel / air mixture. The cylinder bore 4 is formed on a cylindrical surface having a predetermined roundness by a finishing process such as a honing process in order to keep the air-fuel mixture and gas generated by combustion confidential. That is, during actual operation of the engine manufactured using the cylinder block 1, the biston slides back and forth due to the explosion and combustion of the air-fuel mixture in the combustion chamber. Thereby, the crankshaft (output shaft) connected via the piston and the connecting rod (connecting rod) rotates.

  The cylinder part 5 is a wall-like part surrounding the cylinder bore 4. The cylinder portion 5 is formed in a substantially cylindrical shape so as to correspond to each cylinder bore 4 in the cylinder block 1.

  The cylinder bore 4 is formed on the inner peripheral surface side of the cylinder portion 5 by a cylinder liner 9 that is built in by casting or press fitting. The cylinder liner 9 is a member configured in a cylindrical shape using cast iron as a material. That is, the inner peripheral surface of the cylinder liner 9 becomes a wall surface (hereinafter referred to as “bore wall surface”) 4a forming the cylinder bore 4 and serves as a sliding surface of the piston. In addition, although the cylinder block 1 of this embodiment is the structure in which the cylinder bore 4 is formed using the cylinder liner 9, it is not limited to this. The cylinder bore 4 may be formed directly on the structure of the cylinder block 1, for example, when the cylinder block 1 is made of an iron-based material such as cast iron.

  The water jacket 6 is a passage for cooling water, and is formed so as to surround the four cylinder bores 4 when the cylinder block 1 is cast. The water jacket 6 is provided to the cylinder bore 4 via the cylinder portion 5. The cylinder portion 5 is a cylindrical wall-shaped portion formed so as to surround the cylinder bore 4 around the cylinder bore 4, that is, around the cylinder liner 9. As shown in FIG. 2, the cylinder portion 5 is in a state where a cylindrical portion is connected to the adjacent cylinder bore 4.

  Therefore, the water jacket 6 includes an outer peripheral surface (an inner surface of the water jacket 6, hereinafter referred to as “cylinder portion outer peripheral surface”) 15 and an outer peripheral wall surface (the water jacket 6) formed so as to face the water jacket 6. The outer surface of the head mounting surface 3 is formed so as to open to the head mounting surface 3 side. That is, the cylinder block 1 of the present embodiment has an open deck type structure in which the water jacket 6 is opened to the head mounting surface 3 side. The cylinder bore 4 and the like are cooled by the water jacket 6 through the cylinder portion 5.

  In the present embodiment, honing for obtaining a predetermined roundness for the cylinder bore 4 is performed as finishing for the cylinder bore 4. As shown in FIG. 1, honing is performed using a configuration including a horn head (also referred to as “honing head”) 41 and a horn guide 42. The horn head 41 has a honing grindstone 43 and moves relative to the cylinder bore 4 to constitute a head portion that causes the grindstone 43 to act on the cylinder bore 4. The horn guide 42 is provided so as to be movable toward and away from the head mounting surface 3 and constitutes a guide portion for guiding the horn head 41.

  The honing process is performed by a honing apparatus. Such an apparatus is provided with honing means having a horn head 41 and a horn guide 42. This honing means is used to grind the bore wall surface 4a.

  The horn head 41 is configured in a substantially cylindrical shape as a whole, and has a grindstone 43 on its outer peripheral surface. The horn head 41 is configured at the tip (lower end) of the main shaft 44. The main shaft 44 is provided so as to be able to move in the vertical direction (moving in the axial direction) and rotate about its axis as a rotation axis by a driving means (not shown). In other words, the horn head 41 is provided in a state in which it can move up and down (axial movement) and rotational movement via the main shaft 44.

  The grindstone 43 is annularly arranged on the outer peripheral surface portion of the horn head 41, for example, at an equal interval in the circumferential direction. The grindstone 43 is provided on the radially outer side of the horn head 41 so as to be displaceable. That is, when honing the cylinder bore 4, the grindstone 43 acts on the bore wall surface 4a with the rotational movement of the horn head 41 and the like while being pressed against the bore wall surface 4a due to the radially outward displacement. As a configuration for providing the grindstone 43 so as to be displaceable radially outward of the horn head 41, for example, the movement of the rod member provided in the horn head 41 and coaxially with the main shaft 44 is moved in the axial direction. A well-known mechanism with a tapered surface for converting to radial movement is used. That is, in this case, the grindstone 43 is displaced outwardly in the radial direction of the horn head 41 by a taper action or the like by the tapered surface.

  A guide pad 45 is provided on the outer peripheral surface of the horn head 41. The guide pad 45 is used to guide the insertion of the horn head 41 into the cylinder bore 4 and to position the horn head 41 in the cylinder bore 4 by making contact with the bore wall surface 4a when honing the cylinder bore 4. . For example, the guide pad 45 is provided between the adjacent grindstones 43 and is fixed to the main body of the horn head 41 by using a fastener such as a bolt.

  The horn guide 42 has a configuration for positioning the horn head 41 with respect to the cylinder bore 4. The horn guide 42 has a guide hole 42 a for allowing the horn head 41 including the main shaft 44 to move up and down, and guides the horn head 41 up and down with respect to the cylinder bore 4. The horn guide 42 is provided so as to be movable in the proximity and separation direction with respect to the head mounting surface 3, that is, in the vertical direction.

  In the honing process, the horn head 41 is guided by the horn guide 42 positioned at a predetermined position with respect to the cylinder bore 4, and the bore wall surface 4 a is ground by the grindstone 43 by the rotational movement of the horn head 41. Is done. That is, during the honing process, the horn guide 42 is stopped at a predetermined position in the approaching / separating direction with respect to the head mounting surface 3, that is, in a state of being separated from the head mounting surface 3 by a predetermined distance. The horn head 41 is guided by the horn guide 42.

  In the configuration as described above, the processing method of the cylinder block 1 of the present embodiment (hereinafter simply referred to as “processing method”) is performed in a state where the cylinder bore 4 is subjected to a predetermined deformation that makes the cylinder bore 4 non-circular. The cylinder bore 4 is subjected to a finishing process (honing process) for obtaining a predetermined roundness. Here, the predetermined deformation in which the cylinder bore 4 has a non-circular shape includes the following deformation.

  In the cylinder block 1 of the present embodiment, as described above, the bolt fastening portions 10 (bolt holes 12) for fastening and fixing the cylinder head to the head mounting surface 3 are arranged at approximately equal intervals around the cylinder bore 4. Are provided. As shown in FIG. 3, in each bolt fastening part 10, the head bolt 11 is screwed into the bolt hole 12 formed in the cylinder block.

  When the cylinder head is not fixed by tightening the head bolt 11 screwed into the bolt hole 12, that is, when the cylinder block 1 is a single product, the cylinder block 1 receives a tightening force (fastening force) by the head bolt 11. Not in a state. In the cylinder block 1 in such a state, deformation due to the tightening force by the head bolt 11 does not occur, and bore deformation does not occur.

  On the other hand, as shown in FIG. 3A, when the head bolt 11 is tightened and the cylinder head is fastened and fixed to the cylinder block 1, the tightening force by the head bolt 11 is applied to the cylinder block 1. Works. The tightening force by the head bolt 11 causes the cylinder block 1 to be deformed and bore deformation. Bore deformation (hereinafter referred to as “assembly deformation”) due to the assembly of such a cylinder head is caused by strongly pressing the upper surface of the bore (periphery of the cylinder bore 4 on the head mounting surface 3) by tightening the head bolt 11. Arise.

  Therefore, as for the assembly deformation, the deformation increases around the bolt that is particularly strongly pressed on the upper surface of the bore. For this reason, as shown in FIG. 3A, in the configuration in which the bolt fastening portions 10 are provided at approximately four intervals around the cylinder bore 4 as in the present embodiment, the bolt fastening portion 10 A corresponding phase (hereinafter referred to as a “bolt phase”) is deformed such that it swells inward (relatively bulges inward) (see arrow A1). As a result, as shown in FIG. 3A, the assembly deformation is a deformation (so-called quaternary deformation) in which the cylinder bore 4 that is circular in plan view has a cross shape. Further, the bore deformation caused by the heat load during actual operation of the engine is a deformation in which the cross shape is emphasized in the cylinder bore 4 deformed by the assembly deformation. Such quaternary deformation is likely to occur at a height position corresponding to the bottom of the water jacket 6 in the cylinder bore 4.

  For such bore deformation (fourth-order deformation) that occurs during actual operation of the engine, when the cylinder bore 4 is finished, the cylinder bore 4 is in the opposite direction to the bore deformation that occurs during actual operation of the cylinder bore 4 (such that the bore deformation is canceled out). By giving deformation (reverse deformation), bore deformation during engine operation is suppressed. That is, the cylinder block 1 is assembled to the cylinder block 1 after the cylinder bore 4 is finished. However, when the cylinder bore 4 is finished, the cylinder head 1 is reversely deformed, The reverse deformation is canceled out by the assembly and the thermal load during engine operation, and the bore deformation during engine operation is suppressed. In other words, when the cylinder bore 4 is reversely deformed, the cylinder bore 4 approaches a perfect circular shape during engine operation due to assembly deformation and deformation due to a thermal load.

  Therefore, the reverse deformation with respect to the quaternary deformation as shown in FIG. 3A is a deformation in the opposite direction to the quaternary deformation, that is, the bolt phase portion is relatively expanded outward as shown in FIG. It becomes the deformation that comes out.

  In addition, there is a so-called secondary deformation as a bore deformation that occurs during engine operation. As shown in FIG. 4A, the secondary deformation is a deformation such that the cylinder bore 4 has an elliptical shape. Here, the elliptical shape, which is a deformed shape of the cylinder bore 4, has a long axis direction perpendicular to the axial direction of the crankshaft supported by the cylinder block 1 (see the straight line CL, hereinafter referred to as “crankshaft direction”). (Vertical direction in FIG. 4). One of the causes of such secondary deformation is that the part between the four cylinder bores 4 (between the bores) with the crankshaft direction in series in the cylinder block 1 in relation to the other parts during engine operation. It is mentioned that it becomes comparatively high temperature. Accordingly, the secondary deformation is likely to occur in the two intermediate cylinder bores 4 sandwiched between the bores among the four cylinder bores 4 of the cylinder block 1. Further, the secondary deformation is likely to occur in the upper portion (portion on the head mounting surface 3 side) where the cylinder bore 4 is relatively hot.

  As shown in FIG. 4B, the reverse deformation to the secondary deformation as shown in FIG. 4A is a reverse deformation to the secondary deformation, that is, the major axis direction is the crankshaft direction (see the straight line CL). The deformation becomes an elliptical shape.

  As described above, the reverse deformation (see FIG. 3B) for the fourth deformation and the reverse deformation for the second deformation (see FIG. 4B) Thus, the cylinder bore 4 is included in a predetermined deformation that is given when the cylinder bore 4 is finished, so that the cylinder bore 4 has a non-circular shape. That is, the reverse deformation with respect to each of the quaternary deformation and the secondary deformation is a targeted deformation of the bore deformation given when the cylinder bore 4 is finished. In the following description, a predetermined deformation that is given when the cylinder bore 4 is finished, including quaternary deformation and reverse deformation of the secondary deformation, is referred to as “target deformation”.

  In the present embodiment, when the cylinder bore 4 is finished, the following method is used in order to impart targeted deformation to the cylinder bore 4. That is, in the processing method of the present embodiment, a deformation load (hereinafter simply referred to as “deformation load”) that is a load for imparting targeted deformation to the cylinder bore 4 is applied to the cylinder block 1 and the bore wall surface. With respect to the radial displacement amount of the cylinder bore 4a (hereinafter referred to as “bore wall surface displacement amount”), feedback control is performed to control the amount of adjustment of the deformation load. Here, the feedback control for the bore wall surface displacement amount is performed based on a difference between a target value set in advance according to the target deformation and a detection value obtained by detecting the bore wall surface displacement amount. .

  Since such a processing method is performed, in the processing jig for the cylinder block 1 (hereinafter simply referred to as “processing jig”), deformation load applying means for applying a deformation load to the cylinder block 1 is provided. By performing feedback control on the deformation load adjusting means for adjusting the magnitude of the deformation load applied by the deformation load applying means, the displacement amount detecting means for detecting the bore wall surface displacement amount, and the bore wall surface displacement amount, the deformation is performed. Arithmetic control means for controlling an adjustment amount of the magnitude of the deformation load by the load adjusting means is provided.

  As shown in FIG. 1, in the processing jig of the present embodiment, as a deformation load applying means for applying a deformation load to the cylinder block 1, a pressing piece 20, a piston rod 35, and the above-described horn guide. 42 is provided.

  The pressing piece 20 is configured to have a rigidity that can press against the cylinder portion 5 of the cylinder block 1. In the present embodiment, the material constituting the main body of the cylinder block 1 is aluminum, while the material constituting the pressing piece 20 is, for example, an iron-based material. Thereby, the pressing piece 20 is configured to have higher rigidity than the main body of the cylinder block 1.

  As shown in FIG. 5, the pressing piece 20 has two pressing portions 21 and 22 that are connected to each other so as to be separated from each other. Each of the pressing portions 21 and 22 is configured as a plate-like portion, and is in a state in which one end side thereof is connected by the connecting portion 24 while facing each other. The pressing portions 21 and 22 are configured to be separated from each other by elastic deformation of the connecting portion 24 in a state where one end side is connected by the connecting portion 24. That is, the pressing piece 20 is configured to spread from the other end side of the pressing portions 21 and 22 (the side opposite to the connecting portion 24 side, hereinafter referred to as “opening side”). Due to the spread of the pressing piece 20 from the opening side, a predetermined portion of the cylinder portion outer peripheral surface 15 that forms the inner surface of the water jacket 6 is pressed.

  The pressing piece 20 has a shape and a size that can be inserted into the water jacket 6, and is inserted into the water jacket 6 from the connecting portion 24 side (with the connecting portion 24 side as the leading end side). The pressing piece 20 is inserted into the water jacket 6 and is in a state where the outer peripheral surface is substantially in contact with the formation surface of the water jacket 6 (a state having a slight gap). Therefore, the pressing piece 20 has a curved shape along the wall surface that forms the water jacket 6 in the pressing portions 21 and 22, and the connecting portion 24 has a shape along the shape of the bottom portion of the water jacket 6. As the shape of the water jacket 6.

  As described above, the pressing piece 20 has a configuration in which the pressing portions 21 and 22 are separated from each other so as to spread from the opening side, and the pressing direction with respect to the outer peripheral surface 15 of the cylinder portion is included in the spreading direction (separating direction). Inserted into the water jacket 6 as shown in FIG. That is, the pressing piece 20 is inserted into the water jacket 6, one pressing portion 21 is positioned inside the water jacket 6, and the other pressing portion 22 is positioned outside the water jacket 6. Become. Accordingly, the pressing piece 20 has an outer peripheral surface 21a of the inner pressing portion 21 (hereinafter also referred to as “inner pressing portion 21”) facing (substantially contacting) the outer peripheral surface 15 of the cylinder portion and an outer pressing portion 22 ( (Hereinafter also referred to as “outer pressing portion 22”) is inserted into the water jacket 6 so that the outer peripheral surface 22 a faces (substantially contacts) the outer jacket outer surface 16.

  Thus, the direction in which the pressing piece 20 spreads (the direction in which the inner pressing portion 21 and the outer pressing portion 22 are separated) includes the pressing direction with respect to the cylinder portion outer peripheral surface 15. That is, when the pressing piece 20 in the water jacket 6 spreads (the inner pressing portion 21 and the outer pressing portion 22 are separated), the outer pressing portion 22 (the outer peripheral surface 22a) presses the jacket outer surface 16. The cylinder portion outer peripheral surface 15 is pressed by the inner pressing portion 21 (the outer peripheral surface 21a thereof).

  Further, the pressing piece 20 receives a wedge action in a direction in which the pressing portions 21 and 22 are separated from each other via the wedge surface 23. The pressing piece 20 is inserted into the water jacket 6 in such a posture that the wedge action is obtained. The pressing piece 20 obtains a wedge action by pressing a member (piston rod 35) engaged with the wedge surface 23 (wedge engagement) from the opening side. That is, the wedge surface 23 of the pressing piece 20 is a substantially V-shaped surface that is formed between the inner pressing portion 21 and the outer pressing portion 22 and gradually narrows toward the connecting portion 24 side. Specifically, the wedge surface 23 is substantially V-shaped by an inclined surface 21b formed on the outer pressing portion 22 side in the inner pressing portion 21 and an inclined surface 22b formed on the inner pressing portion 21 side in the outer pressing portion 22. Formed.

  In this way, the pressing piece 20 functions as a pressing member having pressing portions 21 and 22 that are detachably connected to each other and a wedge surface 23 that receives a wedge action in a direction in which the pressing portions 21 and 22 are separated from each other. .

  The piston rod 35 engages with the wedge surface 23 of the pressing piece 20. The piston rod 35 has a wedge portion 30 that engages with the wedge surface 23 to provide a wedge action. Specifically, most of the piston rod 35 is configured as a rod-shaped portion having a diameter that can be inserted into the water jacket 6, and has a wedge portion 30 on one end side (lower end side) of the rod-shaped portion.

  As shown in FIG. 5, the wedge part 30 includes a first slope 31 a corresponding to the slope 21 b of the inner pressing part 21 and a second slope 32 a corresponding to the slope 22 b of the outer pressing part 22. It has a V shape corresponding to the substantially V shape. That is, the wedge part 30 engages with the pressing piece 20 (wedge engagement) by bringing the first inclined surface 31a and the second inclined surface 32a into contact with the inclined surface 21b and the inclined surface 22b on the pressing piece 20 side, respectively. Then, when the wedge portion 30 in a state of being engaged with the pressing piece 20 is pressed from the opening side of the pressing piece 20, the pressing piece 20 obtains a wedge action. Due to this wedge action, a predetermined portion of the cylinder portion outer peripheral surface 15 is pressed.

  That is, the wedge action obtained by the pressing piece 20 is an action in which the pressing piece 20 spreads from the opening side (the inner pressing portion 21 and the outer pressing portion 22 are separated from each other). The predetermined part is pressed. As described above, the pressing piece 20 is inserted into the water jacket 6 in such a posture that the opening side is the opening side (upper side) with respect to the head mounting surface 3 of the water jacket 6.

  In addition, below the wedge surface 23 of the pressing piece 20 (on the connecting portion 24 side), the spreading of the pressing piece 20 (separation between the inner pressing portion 21 and the outer pressing portion 22), that is, the wedge portion that accompanies the pressing of the wedge portion 30. A recess 25 for allowing 30 movements is provided. Moreover, between the pressing piece 20 and the wedge part 30, the pressing piece 20 with the wedge part 30 engaged can be prevented from moving along the shape of the water jacket 6 as necessary. A slip prevention mechanism is provided. Further, the pressing force of the pressing piece 20 against the outer peripheral surface 15 of the cylinder part is adjusted by the angle of the wedge surface 23, the magnitude of the force pressing the wedge part 30, and the like.

  The pressing piece 20 is supported with respect to the piston rod 35 in a state in which the wedge portion 30 can be engaged. In a state where the pressing piece 20 is supported by the piston rod 35, the wedge portion 30 is interposed between the inner pressing portion 21 and the outer pressing portion 22 in the pressing piece 20. When the pressing piece 20 is supported with respect to the piston rod 35, the wedge portion 30 can be engaged with the pressing piece 20. That is, the state in which the wedge portion 30 can be engaged here is that the wedge portion 30 is interposed between the inner pressing portion 21 and the outer pressing portion 22, and the first inclined surface 31a of the wedge portion 30 is pressed inward. The second inclined surface 32 a faces the inclined surface 21 b of the portion 21 and the inclined surface 22 b of the outer pressing portion 22, and the wedge portion 30 is pressed against the pressing piece 20, thereby engaging the pressing piece 20. It is a state that matches.

  In order to support the pressing piece 20 to the piston rod 35, a gap 26 is provided between the inner pressing portion 21 and the outer pressing portion 22 on the opening side of the pressing piece 20 (see FIG. 5). The gap 26 restricts the wedge portion 30 provided at the lower end portion of the piston rod 35 from coming off from the opening side. Thus, the pressing piece 20 is in a state of being locked with respect to the wedge portion 30 of the piston rod 35 through the gap 26.

  The piston rod 35 is provided so as to be urged in a direction (downward direction, hereinafter referred to as “pressing direction”) that applies at least a wedge action to the pressing piece 20 by hydraulic pressure that is an example of fluid pressure. That is, when the piston rod 35 in a state where the wedge portion 30 is engaged with the wedge surface 23 of the pressing piece 20 is urged in the pressing direction, the wedge portion 30 is pressed from the opening side of the pressing piece 20 and the wedge action is performed. can get.

  Specifically, as shown in FIG. 6, the piston rod 35 has a piston portion 35 a that is an enlarged diameter portion on the other end side (upper end side) of the rod-shaped portion. The piston rod 35 is provided so as to be urged at least downward (pressing direction) by hydraulic pressure, as described above, by being supported so as to be slidable in the vertical direction with its upper end portion housed in the hydraulic chamber 36. It is done. That is, the piston portion 35 a of the piston rod 35 is a plug-like portion having a shape that can slide with respect to the side wall surface that forms the hydraulic chamber 36. In this way, the hydraulic chamber 36 functions as a fluid pressure chamber that supports the piston rod 35 so as to be movable in a predetermined sliding direction (vertical direction) including the pressing direction, and that applies hydraulic pressure to the piston rod 35.

  The piston rod 35 receives a load in the pressing direction by being biased downward by receiving hydraulic pressure through the piston portion 35a in the hydraulic chamber 36 (see arrow F1). When the piston rod 35 receives a load in the pressing direction, a wedge action is applied to the pressing piece 20 with which the wedge portion 30 engages. A predetermined portion on the outer peripheral surface 15 of the cylinder portion is pressed by the pressing piece 20 having such a wedge action (see arrow N1).

  That is, the pressing piece 20 in the state inserted in the water jacket 6 obtains a wedge action from the piston rod 35 that receives the hydraulic pressure in the hydraulic chamber 36 as a load in the pressing direction via the wedge part 30, and thereby the inner pressing part. 21 and the outer pressing portion 22 are separated from each other (see FIG. 5). Thereby, the jacket outer surface 16 is pressed by the outer peripheral surface 22a of the outer pressing portion 22, and the cylinder portion outer peripheral surface 15 is pressed by the outer peripheral surface 21a of the inner pressing portion 21 (see arrow N1).

  Thus, in this embodiment, the piston rod 35 and the hydraulic chamber 36 constitute a hydraulic cylinder mechanism. A hydraulic cylinder mechanism including the piston rod 35 and the hydraulic chamber 36 is provided for each of the plurality of pressing pieces 20 inserted into the water jacket 6.

  As described above, the piston rod 35 has the wedge portion 30 that engages with the wedge surface 23 to give a wedge action, and functions as a pressing member that can be urged at least in the pressing direction by hydraulic pressure.

  In the present embodiment, as described above, honing is performed as a finishing process for the cylinder bore 4 using a configuration including the horn head 41 and the horn guide 42. Therefore, in the present embodiment, as shown in FIG. 6, the horn guide 42 is provided with a hydraulic chamber 36 that supports the piston rod 35 and applies hydraulic pressure to the piston rod 35.

  That is, in this embodiment, the hydraulic chamber 36 that constitutes the hydraulic cylinder mechanism together with the piston rod 35 is provided in the horn guide 42 that constitutes the honing means for performing the honing process on the cylinder bore 4. Specifically, as described above, in the horn guide 42 that is positioned at a predetermined position with respect to the cylinder bore 4 during the honing process, the hydraulic chamber 36 has the piston rod 35 to be supported inserted into the water jacket 6. It is provided at a position corresponding to the pressing piece 20 to be pressed.

  As described above, in the present embodiment, the horn guide 42 supports the piston rod 35 so as to be movable in a predetermined sliding direction including the pressing direction, and forms a hydraulic chamber 36 that applies hydraulic pressure to the piston rod 35. It functions as a pressure chamber forming member. That is, in this embodiment, the fluid pressure chamber forming member that forms the hydraulic chamber 36 is a horn guide 42 that is a member that forms a guide portion in the honing means.

  Thus, by providing the hydraulic chamber 36 constituting the hydraulic cylinder mechanism for urging the piston rod 35 in the horn guide 42 used for honing processing for the cylinder bore 4, the piston rod 35 is supported and the piston rod 35 is supported. When applying the hydraulic pressure, an existing configuration used for honing of the cylinder bore 4 can be used, and it is not necessary to separately provide a configuration for supporting the piston rod 35 and the like. Thereby, simplification of an apparatus structure and improvement of workability | operativity can be aimed at.

  In the present embodiment, the hydraulic chamber 36 for supporting the piston rod 35 and the like is provided in the horn guide 42 as an existing configuration, but is not limited thereto. That is, a member provided separately from the horn guide 42 may be used as the fluid pressure chamber forming member that forms the hydraulic chamber 36.

  In this embodiment, hydraulic pressure is used as the fluid pressure for biasing the piston rod 35 constituting the deformation load applying means at least in the pressing direction, but other fluid pressure such as air pressure is used. May be used. For example, when air pressure is used as the fluid pressure, an air cylinder mechanism is configured as the deformation load applying means including the piston rod 35.

  In this way, the pressing of the pressing piece 20 from the piston rod 35 on the cylinder portion outer peripheral surface 15 by the wedge action is performed on the bolt phase portion of the cylinder portion outer peripheral surface 15 in this embodiment. That is, the pressing piece 20 is inserted into a position corresponding to the bolt phase portion of the cylinder portion outer peripheral surface 15 of the water jacket 6 and is also in contact with the outer peripheral surface 15 of the inner pressing portion 21. Has a size (area) corresponding to the bolt phase portion on the outer peripheral surface 15 of the cylinder portion.

  Here, the bolt phase is a phase corresponding to the bolt fastening portion 10 in the circumferential shape of the cylinder bore 4, and the “phase” in the circumferential shape of the cylinder bore 4 is as follows. That is, the cylinder bore 4, which is a cylindrical hole, has a circumferential shape when viewed in the central axis direction. In the circumferential shape of the cylinder bore 4, an angle on the circumference around the position of the central axis is determined. This angle (angle range) is a “phase” in the circumferential shape of the cylinder bore 4.

  Therefore, the bolt phase is an angle on the circumference centered on the position C of the central axis when viewed in the direction of the central axis where the cylinder bore 4 has a circumferential shape, as shown for the leftmost cylinder bore 4 in FIG. Is a predetermined angle range α1 in the direction including the bolt fastening portion 10 and the vicinity thereof from the center (position C). In the configuration in which four bolt fastening portions 10 are provided at substantially equal intervals around the cylinder bore 4 as in the present embodiment, the phase (angle range α1) corresponding to the bolt fastening portion 10 as described above is set to each cylinder bore. There will be four locations in FIG. Note that the magnitude of the angle of the predetermined angle range α1 with respect to the bolt phase is not particularly limited, and in the cylinder bore 4 is a portion constricted inward by a bolt axial force due to fastening of the head bolt or a thermal stress during engine operation. The corresponding angle range is set as appropriate. Hereinafter, other phases (other phases) are referred to as “non-volt phases” with respect to the bolt phases.

  Further, the height (vertical length) range of the pressing portion of the pressing piece 20 against the cylinder portion outer peripheral surface 15 is the height (vertical length) of the pressing piece 20 inserted in the water jacket 6. Is equivalent to That is, the arrow range indicated by reference sign H <b> 1 in FIG. 5 corresponds to the height of the pressing piece 20, and the outer peripheral surface 21 a of the inner pressing portion 21 is a portion that contacts the cylinder portion outer peripheral surface 15. And the part where the outer peripheral surface 21a of the inner side press part 21 contacts the cylinder part outer peripheral surface 15 becomes the height range about the press part with respect to the cylinder part outer peripheral surface 15 by the pressing piece 20. FIG. The height range (the height of the pressing piece 20) of the pressing portion with respect to the cylinder portion outer peripheral surface 15 by the pressing piece 20 is appropriately set according to the shape of the cylinder block 1 and the like.

  Thus, in the cylinder part outer peripheral surface 15, the predetermined | prescribed part pressed by the pressing piece 20 used as the part which the outer peripheral surface 21a of the inner side press part 21 contacts is a part of a bolt phase (refer angle range (alpha) 1). Thus, it becomes a portion in a height range corresponding to the height of the pressing piece 20 inserted into the water jacket 6 (see reference numeral H1). In the present embodiment where there are ten bolt fastening portions 10 in the cylinder block 1 and ten bolt phase portions, each of a total of ten pressing pieces 20 inserted into each bolt phase portion, Ten hydraulic cylinder mechanisms including the piston rod 35 are provided. Therefore, in the present embodiment, the hydraulic chamber 36 provided in the horn guide 42 is provided in the horn guide 42 at a position corresponding to the bolt phase portion in a plan view (ten locations). As described above, the pressing piece 20 supported by the piston rod 35 by being locked to the wedge part 30 is in a state where all the pressing pieces 20 are inserted into the water jacket 6 at the respective arrangement positions. -It supports so that the pressing direction with respect to the part of the bolt phase in the cylinder part outer peripheral surface 15 may be included in the direction which 22 separates.

  However, the pressing position with respect to the cylinder part outer peripheral surface 15 when the pressing piece 20 obtains a wedge action from the piston rod 35 is not limited to the bolt phase portion as in this embodiment. That is, when the pressing position (the position where the pressing piece 20 is inserted) with respect to the cylinder portion outer peripheral surface 15 is a bolt phase portion as in the present embodiment, the reverse deformation of the quaternary deformation is performed as the target deformation of the cylinder bore 4. It can be easily applied and is mainly effective for fourth-order deformation. However, a non-bolt phase portion may be pressed on the outer peripheral surface 15 of the cylinder portion, for example, when a reverse deformation of a secondary deformation is given as a targeted deformation of the cylinder bore 4.

  As described above, in this embodiment, the deformation load applying means having the pressing piece 20, the piston rod 35, and the horn guide 42 is a predetermined portion (bolt) on the cylinder outer peripheral surface 15 as the deformation load. A pressing force is applied to the phase portion. The pressing force is applied to a predetermined portion (bolt phase portion) in a direction in which the pressing portions 21 and 22 are separated from each other by the piston rod 35 being urged in the pressing direction by the hydraulic pressure supplied to the hydraulic chamber 36. The pressing piece 20 having a posture including the direction is obtained by receiving a wedge action.

  Further, as shown in FIG. 1, the processing jig of the present embodiment has a configuration having an electromagnetic switching valve 37 as a deformation load adjusting means for adjusting the magnitude of the deformation load applied by the deformation load applying means. Provided.

  As shown in FIG. 6, the hydraulic cylinder mechanism including the piston rod 35 and the hydraulic chamber 36 is configured as a single-rod type double-acting cylinder in which the piston rod 35 protrudes from one side (lower side) of the hydraulic chamber 36. Is done. That is, in the hydraulic chamber 36, two upper and lower hydraulic chambers 36a and 36b are formed via the piston portion 35a of the piston rod 35, and an oil inlet / outlet is provided in each of the hydraulic chambers 36a and 36b. Then, the oil inlet / outlet of each of the hydraulic chambers 36a, 36b becomes an oil inlet / outlet by switching the circuit, whereby the piston rod 35 is reciprocated (lowered and raised) in the vertical direction.

  Accordingly, when the hydraulic oil is supplied to the hydraulic chamber 36 a above the piston portion 35 a in the hydraulic chamber 36, the piston rod 35 is lowered (biased in the pressing direction), and the wedge 30 presses against the pressing piece 20. The action is given. On the other hand, when the hydraulic oil is supplied to the hydraulic chamber 36b below the piston portion 35a in the hydraulic chamber 36, the piston rod 35 is raised (biased in the direction opposite to the pressing direction). In the following description, the hydraulic chamber 36a above the piston portion 35a where the piston rod 35 is lowered when the pressure oil is supplied is referred to as a “lowering hydraulic chamber 36a”, and the piston is supplied with the pressure oil. The hydraulic chamber 36b below the piston portion 35a in which the rod 35 is raised is referred to as a “rising hydraulic chamber 36b”.

  Then, switching of the supply of pressure oil to the descending hydraulic chamber 36a and the ascending hydraulic chamber 36b (circuit switching) is performed by the electromagnetic switching valve 37. The electromagnetic switching valve 37 is configured as a so-called solenoid operation switching valve, and includes a solenoid (electromagnet) operated via a relay in response to a predetermined control signal (electric signal), and a spool that is moved by the force of the solenoid. The flow path of the hydraulic circuit is switched by the operation of the spool. That is, the electromagnetic switching valve 37 is configured as a valve mechanism called OCV (oil control valve). The electromagnetic switching valve 37 adjusts the supply of pressure oil to the descending hydraulic chamber 36a and the ascending hydraulic chamber 36b (switching the flow path and adjusting the oil amount), that is, the hydraulic pressures of the descending hydraulic chamber 36a and the ascending hydraulic chamber 36b. The pressure is increased / decreased.

  That is, oil in an oil tank (not shown) is supplied to the hydraulic chamber 36 by a hydraulic pump 38, and adjustment of supply of pressure oil to the descending hydraulic chamber 36a and the rising hydraulic chamber 36b in the hydraulic chamber 36 is performed. This is performed by an electromagnetic switching valve 37 interposed between the hydraulic pump 38 and the hydraulic chamber 36. Specifically, the electromagnetic switching valve 37 includes a port that receives supply of oil from the hydraulic pump 38, a port connected to the descending hydraulic chamber 36a, a port connected to the ascending hydraulic chamber 36b, and other drain ports. And have. A port that receives supply of oil from the hydraulic pump 38 is connected to the oil tank via the hydraulic pump 38. The port connected to the descending hydraulic chamber 36a is connected to the oil inlet / outlet of the descending hydraulic chamber 36a via the oil passage 39a, and the port connected to the rising hydraulic chamber 36b is elevated via the oil passage 39b. It is connected to the oil inlet / outlet of the hydraulic chamber 36b.

  In such a hydraulic circuit configuration, the circuit states switched by the electromagnetic switching valve 37 include at least the following two states. One is that oil supplied by the hydraulic pump 38 is supplied from the oil passage 39a into the lowering hydraulic chamber 36a via the electromagnetic switching valve 37, and oil in the rising hydraulic chamber 36b is supplied from the oil passage 39b to the electromagnetic switching valve. This is a state (first state) discharged through 37. The other is that oil supplied by the hydraulic pump 38 is supplied from the oil passage 39b into the rising hydraulic chamber 36b via the electromagnetic switching valve 37, and the oil in the lowering hydraulic chamber 36a is electromagnetically switched from the oil passage 39a. This is a state (second state) discharged through the valve 37. That is, in the first state, the piston rod 35 is lowered, and in the second state, the piston rod 35 is raised.

  With the hydraulic circuit configuration as described above, the hydraulic pressure in the hydraulic chamber 36, that is, the magnitude of the deformation load applied to the cylinder block 1 via the piston rod 35 and the pressing piece 20 is adjusted. That is, an instruction (control signal) is sent to the electromagnetic switching valve 37 so that the hydraulic pressure in the hydraulic chamber 36 is large enough to cause the cylinder bore 4 to be deformed by the deformation load, and the electromagnetic switching valve 37 is controlled. . The electromagnetic switching valve 37 thus controlled adjusts the supply of pressure oil to the descending hydraulic chamber 36a and the ascending hydraulic chamber 36b, that is, adjusts the magnitude of the deformation load.

  As described above, in the processing jig of the present embodiment, the magnitude of the deformation load (the pressing force on the outer peripheral surface 15 of the cylinder portion) applied by the configuration including the pressing piece 20, the piston rod 35, and the horn guide 42 is large. As a deformation load adjusting means for adjusting the above, a configuration having an electromagnetic switching valve 37 is used. That is, in the present embodiment, the deformation load adjusting means includes the electromagnetic switching valve 37 as a valve mechanism that adjusts the supply of hydraulic pressure to the hydraulic chamber 36.

  As shown in FIG. 1, the machining jig of the present embodiment is provided with a displacement sensor 50 as a displacement amount detecting means for detecting the bore wall surface displacement amount.

  The displacement sensor 50 has the bore wall surface 4a as a measurement target surface, and the center axis direction (hereinafter referred to as “bore axial direction”) and the circumferential direction (hereinafter referred to as “bore circumferential direction”) of the cylinder bore 4 on the bore wall surface 4a. It is a gap sensor which detects the amount of displacement of the bore wall surface of a predetermined detection part. The displacement sensor 50 outputs a signal corresponding to the distance (see reference numeral g1 shown in FIG. 8) between the bore wall portion 4a and a predetermined detection portion, and detects the bore wall surface displacement amount. That is, the detection signal output from the displacement sensor 50 corresponds to the bore wall surface displacement amount, and the bore wall surface displacement amount is obtained based on this detection signal.

  As the displacement sensor 50, a known gap sensor can be used, and the type thereof is not particularly limited, such as a non-contact sensor or a contact sensor. That is, the displacement sensor 50 is referred to as bore deformation (hereinafter referred to as “bore deformation related to pressing of the cylinder portion outer peripheral surface 15”) caused by the pressing force applied to the cylinder portion outer peripheral surface 15 by the pressing piece 20 obtaining a wedge action from the piston rod 35. ) To the extent that the displacement in the radial direction of the cylinder bore 4 of the bore wall surface 4a can be detected (accuracy on the order of μm). Specifically, as the displacement sensor 50, for example, an eddy current type or a capacitance type sensor, a laser sensor, an ultrasonic sensor, or the like can be used.

  In the present embodiment, the displacement sensor 50 is supported by a sensor piston 51 as a piston member that can be inserted into the cylinder bore 4. As shown in FIGS. 7 and 8, the sensor piston 51 is configured to have a substantially cylindrical outer shape as a whole, and has a cylindrical outer peripheral surface portion 51 a that can be inserted into the cylinder bore 4. The sensor piston 51 is slidably mounted on the cylinder bore 4 and supports the displacement sensor 50 on the outer peripheral surface portion 51a.

  The outer diameter of the sensor piston 51 (the diameter of the outer peripheral surface portion 51a) is set slightly smaller than the inner diameter (diameter) of the cylinder bore 4 so that the outer peripheral surface portion 51a can be inserted into the cylinder bore 4. Specifically, the outer diameter of the sensor piston 51 is such that the sensor piston 51 is positioned concentrically with respect to the cylinder bore 4 in the cylinder bore 4 (centered state). It is set to a size that does not hinder the bore deformation associated with the pressure of 15. That is, in a state where the sensor piston 51 is centered with respect to the cylinder bore 4, a clearance (gap) between the outer peripheral surface portion 51a and the bore wall surface 4a is large enough to allow bore deformation related to the pressing of the cylinder outer peripheral surface 15. ) Exists.

  A support hole 51 b for supporting the displacement sensor 50 is provided at a predetermined position on the outer peripheral surface portion 51 a of the sensor piston 51. The support hole 51 b is a hole that opens toward the radially outer side of the cylinder bore 4. The displacement sensor 50 is supported, for example, by being fitted into the support hole 51b.

  As shown in FIG. 8, in the present embodiment, the support hole 51 b that supports the sensor piston 51 is formed by using a lid 52 that is attached to the lower portion of the sensor piston 51. That is, a recess capable of accommodating the displacement sensor 50 is formed on the lower side of the main body of the sensor piston 51, and the support hole 51b is formed by covering the recess from the lower side with the lid body 52.

  The lid body 52 is a plate-like member, and is fixed to the main body of the sensor piston 51 by a stopper 53 such as a bolt in a state of being fitted to a recess formed on the lower side of the main body of the sensor piston 51. Is done. When the plurality of displacement sensors 50 are supported by the sensor piston 51 as shown in FIG. 8, the lid 52 is provided as a member that forms a support hole 51b in which each displacement sensor 50 is supported, or a plurality of displacements. The sensor 50 may be provided as an integral member (for example, an annular member).

  As shown in FIG. 7, in this embodiment, eight displacement sensors 50 are provided at predetermined intervals in the circumferential direction on the outer peripheral surface portion 51a. That is, in the sensor piston 51 of the present embodiment, the eight displacement sensors 50 are supported so as to be radial at substantially equal angular intervals in the circumferential direction of the outer peripheral surface portion 51a.

  These eight displacement sensors 50 are oriented in the following direction (corresponding to the phase of the cylinder bore 4) when the sensor piston 51 is inserted into the cylinder bore 4 (hereinafter referred to as “bore insertion state”). To be arranged at the sensor piston 51. That is, the pair of displacement sensors 50 that are arranged opposite to each other in the radial direction of the sensor piston 51 face both sides in the direction parallel to the crankshaft direction, and the other pair of displacement sensors 50 that are also arranged opposite to each other are It is arranged so as to face both sides of the direction perpendicular to the direction. That is, these four displacement sensors 50 are arranged at equiangular intervals (90 ° intervals) on the outer peripheral surface portion 51 a of the sensor piston 51. The other four displacement sensors 50 are arranged so as to correspond to the respective bolt phases. That is, these four displacement sensors 50 are arranged at substantially equal intervals on the outer peripheral surface portion 51 a of the sensor piston 51 corresponding to the bolt fastening portion 10 (bolt hole 12) provided around the cylinder bore 4.

  Therefore, in this embodiment, the eight displacement sensors 50 detect the bore wall surface displacement amount in a total of eight directions including the direction of the bolt phase, the direction parallel to the crankshaft direction, and the direction perpendicular to the crankshaft direction. . In addition, the figure of the part of the sensor piston 51 in FIG. 8 is equivalent to AA sectional drawing in FIG.

  In the present embodiment, the eight displacement sensors 50 have the same position (hereinafter referred to as “axial position”) in the cylinder axis direction (center axis direction) of the sensor piston 51 in the sensor piston 51. It is provided to become. In other words, the sensor piston 51 has the same position (height position) in the bore axis direction of the eight displacement sensors 50 in the bore insertion state. However, the axial position, that is, the height position, of the eight pistons 51 of the displacement sensors 50 may be appropriately different from each other.

  The sensor piston 51 is provided with a seal material 54. The sealing material 54 is an annular member made of, for example, rubber or metal. The sealing material 54 is provided in a state of being fitted on the outer peripheral surface portion 51 a of the sensor piston 51. The sealing material 54 is supported in a state of being fitted in an outer peripheral groove 51 c formed in the outer peripheral surface portion 51 a of the sensor piston 51.

  The sealing material 54 is positioned on the front side in the insertion direction of the sensor piston 51 with respect to the cylinder bore 4 with respect to the displacement sensor 50 with respect to the axial position of the sensor piston 51. That is, the outer peripheral groove 51 c into which the seal material 54 is fitted is located above the support hole 51 b that supports the displacement sensor 50 in the bore insertion state of the sensor piston 51.

  The sealing material 54 in a state of being externally fitted to the outer peripheral surface portion 51a of the sensor piston 51 is in a state of being in close contact with the bore wall surface 4a over the entire circumference in a bore insertion state of the sensor piston 51. That is, the sensor piston 51 is slidably mounted on the cylinder bore 4 via the seal material 54. For this reason, the sealing material 54 is biased radially outward of the sensor piston 51 by an elastic member 55 such as a spring.

  The elastic member 55 is interposed between the bottom surface (inner surface) of the outer peripheral groove 51 c and the inner peripheral surface of the sealing material 54 in the outer peripheral groove 51 c, and presses the sealing material 54 outward in the radial direction of the sensor piston 51. Energize. As the elastic member 55, for example, a helical spring or a leaf spring is appropriately used. A plurality of elastic members 55 are appropriately arranged in the circumferential direction of the sensor piston 51.

  Thus, in the state where the sealing material 54 is interposed between the outer peripheral surface portion 51a of the sensor piston 51 and the bore wall surface 4a, the distance between the outer peripheral surface portion 51a and the bore wall surface 4a is substantially constant over the entire circumference. It becomes. That is, the cylinder bore 4 that is the columnar hole and the cylindrical sensor piston 51 are in a substantially concentric state (a state in which the sensor piston 51 is substantially centered with respect to the cylinder bore 4) by the seal material 54.

  The sealing material 54 is such that the elastic member 55 does not hinder bore deformation related to the pressing of the cylinder portion outer peripheral surface 15 in the radial direction of the sensor piston 51 (to the extent that the bore deformation related to the pressing of the cylinder portion outer peripheral surface 15 is allowed. ) Is supported in a state having elasticity. Here, the elasticity which sealing material 54 itself has may be used because a sealing material is comprised by the raw material which has elasticity, such as rubber | gum. In this case, the elastic member 55 can be omitted.

  As described above, the seal material 54 is provided in the sensor piston 51, so that deposits (such as chips and foreign matters generated in the previous process of the finishing process) are present on the bore wall surface 4a as the sensor piston 51 is inserted into the cylinder bore 4. ) Is cleaned above the sealing material 54 by the sealing material 54. Thereby, in the bore insertion state of the sensor piston 51, deposits such as chips are removed from the portion to be measured on the bore wall surface 4a by the displacement sensor 50 positioned below the seal material 54. As a result, for the displacement sensor 50 whose detection target is the amount of displacement of the bore wall surface, erroneous detection due to an adhering substance is prevented, and detection accuracy is ensured.

  A plurality of sealing materials 54 may be provided in the sensor piston 51. In such a case, the plurality of sealing materials 54 are provided at predetermined intervals in the cylinder axis direction (center axis direction) of the sensor piston 51.

  The sensor piston 51 having the above-described configuration is supported by the hydraulic cylinder mechanism 56 for insertion into the cylinder bore 4 and positioning with respect to the height position in the cylinder bore 4. As shown in FIG. 1, the hydraulic cylinder mechanism 56 includes a cylinder portion 56a and a rod portion 56b that is provided so that at least a part of the cylinder portion 56a can protrude and retract, and is supplied from a hydraulic source (not shown). It is driven by hydraulic pressure.

  The hydraulic cylinder mechanism 56 is provided in such a posture that the extending / contracting direction, that is, the protruding and retracting direction of the rod portion 56b from the cylinder portion 56a is the vertical direction. And with respect to the hydraulic cylinder mechanism 56, the sensor piston 51 is supported by the front end side (upper end side) of the rod part 56b from the cylinder part 56a. Therefore, the sensor piston 51 is provided to be movable in the vertical direction by the hydraulic cylinder mechanism 56 (see arrow A2). Instead of the hydraulic cylinder mechanism 56, an air cylinder mechanism or the like that is driven by air pressure may be used.

  The movement direction of the sensor piston 51 by the hydraulic cylinder mechanism 56 corresponds to the bore axis direction in the cylinder block 1. That is, when the cylinder bore 4 is finished, the cylinder block 1 serving as a workpiece is supported and fixed in such a posture that the head mounting surface 3 side is on the upper side and the bore axis direction is the vertical direction.

  As shown in FIG. 1, the cylinder block 1 is supported and fixed to the equipment table 57 when the cylinder bore 4 is finished. The equipment table 57 has a work support surface 57a for supporting and fixing the cylinder block 1 as a work. The cylinder block 1 is fixed in a state where the cylinder block 1 is positioned at a predetermined location on the work support surface 57a.

  Thus, the hydraulic cylinder mechanism 56 that supports the sensor piston 51 with respect to the cylinder block 1 that is supported and fixed to the equipment table 57 is inserted into the cylinder bore 4 by the movement of the sensor piston 51 due to its expansion and contraction. It is provided at a possible position. That is, the hydraulic cylinder mechanism 56 is provided at a position where the cylinder axis direction (center axis direction) of the sensor piston 51 supported by the hydraulic cylinder mechanism 56 substantially coincides with the bore axis direction. The hydraulic cylinder mechanism 56 is provided at a height position at which the sensor piston 51 can be inserted into and removed from the cylinder bore 4 according to the expansion / contraction length. The hydraulic cylinder mechanism 56 is supported and fixed on a cylinder support surface 57b of the equipment table 57 via a base portion 56c of the cylinder portion 56a.

  Thus, the sensor piston 51 supported by the hydraulic cylinder mechanism 56 is inserted into the cylinder bore 4 of the cylinder block 1 set in the equipment table 57. Then, when detecting the displacement of the bore wall surface by the displacement sensor 50 supported by the sensor piston 51, the height of the sensor piston 51 by the hydraulic cylinder mechanism 56 is set so that the displacement sensor 50 is at a desired height position with respect to the cylinder bore 4. The position is positioned. With such a configuration, the displacement sensor 50 detects the bore wall surface displacement amount of a predetermined detection site in the bore wall surface 4a in the bore axis direction and the bore circumferential direction.

  In the present embodiment, the sensor piston 51 provided to be movable up and down by the hydraulic cylinder mechanism 56 is used to support the displacement sensor 50, but the configuration for supporting the displacement sensor 50 is not particularly limited. As a configuration for supporting the displacement sensor 50, for example, a horn head 41 for performing a honing process may be used.

  As shown in FIG. 1, the processing jig of the present embodiment includes a feedback control unit 60 as a calculation control unit. The feedback control unit 60 controls the amount of adjustment of the deformation load (the pressing force on the outer peripheral surface 15 of the cylinder unit) by the configuration having the electromagnetic switching valve 37 by performing feedback control on the bore wall surface displacement amount.

  The feedback control unit 60 includes a storage unit for storing a program related to feedback control, a development unit for expanding the program, a calculation unit for performing a predetermined calculation according to the program, a storage unit for storing a calculation result by the calculation unit, and the like. Have. Specifically, the feedback control unit 60 includes a configuration in which a CPU, ROM, RAM, HDD, and the like are connected by a bus, and a configuration that includes a one-chip LSI or the like. As the feedback control unit 60, in addition to a dedicated product, a commercially available personal computer, a workstation or the like in which the above program is stored is used.

  The feedback control unit 60 performs feedback control on the bore wall surface displacement amount based on a difference between a target value set in advance according to the target deformation and a detection value obtained by detecting the bore wall surface displacement amount. The target value for the feedback control is set and stored in advance in the feedback control unit 60. In addition, a detection value for feedback control is obtained from an output signal from the displacement sensor 50.

  Therefore, as shown in FIG. 1, the displacement sensor 50 supported by the sensor piston 51 is connected to the feedback control unit 60 via the cable. Specifically, as shown in FIG. 8, the output signal from each displacement sensor 50 is input to the feedback control unit 60 via the sensor amplifier 61. Note that the feedback control unit 60 may incorporate the function of the sensor amplifier 61.

  The target value in the feedback control is set as follows, for example. As described above, the fourth-order deformation which is one aspect of the bore deformation is a deformation in which the cylinder bore 4 has a cross shape (see FIG. 3A). In the cylinder bore 4 in which such fourth-order deformation has occurred, the radius in the bolt phase portion is relatively shorter than the radius in the non-bolt phase portion. Therefore, when the reverse deformation of the fourth-order deformation (see FIG. 3B) is the target deformation, the radius in the bolt phase portion (see r1 in the figure) that becomes a relatively long radius and the relatively short radius. The magnitude of the difference (radius difference) from the radius (see reference numeral r2 in the figure) in the non-volt phase portion is one of the deformation degree indicators for the bore deformation. Therefore, a target value for each displacement sensor 50 is set so that the radius difference has a predetermined value (for example, 8 μm) corresponding to the target deformation.

  Similarly, when the reverse deformation of the secondary deformation (see FIG. 4B) is the target deformation, the radius in the crankshaft direction (see the straight line CL) that is a relatively long radius and the relatively short radius are similarly applied. The target value for each displacement sensor 50 is set so that the magnitude of the difference (radius difference) from the radius perpendicular to the crankshaft direction becomes a predetermined value corresponding to the target deformation.

  Then, in the feedback control unit 60, an input signal (reference input signal) based on a preset target value and a detection signal (feedback signal) based on a detection value by the displacement sensor 50 are compared, and as a calculation result, A signal based on the difference (deviation) between the target value and the detected value is generated. The signal generated here is an electric signal such as a voltage instruction value, for example, and is sent as a control signal for the electromagnetic switching valve 37 serving as an operation unit for the control target. With this control signal (electrical signal), the operation amount (spool operation amount) in the electromagnetic switching valve 37 is controlled. Such control of the electromagnetic switching valve 37 is performed until the detected value matches the target value.

  Such feedback control for the bore wall surface displacement amount is performed for each cylinder bore 4 in the cylinder block 1, for example. In this case, in order to apply a deformation load to the cylinder bore 4 in which the sensor piston 51 is inserted by feedback control based on detection values from the eight displacement sensors 50 supported by the sensor piston 51 inserted in the cylinder bore 4. The four electromagnetic switching valves 37 are controlled.

  That is, for one cylinder bore 4, four portions are pressed as bolt phase portions on the cylinder portion outer peripheral surface 15. An electromagnetic switching valve 37 is provided via a hydraulic chamber 36 for each piston rod 35 that gives a wedge action to the pressing piece 20 inserted corresponding to these four pressing positions. Therefore, control signals for the four electromagnetic switching valves 37 provided for one cylinder bore 4 are based on detection signals from the eight displacement sensors 50 supported by the sensor pistons 51 inserted into the corresponding cylinder bores 4. Generated. The feedback control for the bore wall surface displacement amount is performed simultaneously or in a predetermined order for the four cylinder bores 4 of the cylinder block 1.

  Thus, the feedback control unit 60 performs feedback control on the bore wall surface displacement amount, thereby adjusting the magnitude of the deformation load by the configuration having the electromagnetic switching valve 37, that is, the amount of adjustment of the hydraulic pressure in the hydraulic chamber 36. Control. As a result, the hydraulic pressure (see arrow F1 in FIG. 6) applied to the piston rod 35 via the hydraulic chamber 36 is adjusted so that the cylinder bore 4 is subjected to targeted deformation.

  As a mode of feedback control for the bore wall surface displacement amount, the radius difference itself due to bore deformation may be set as a target value in the feedback control. In this case, for example, the following values are used as detection values in the feedback control. That is, when the target deformation is a reverse deformation of the fourth-order deformation, for example, any one of the bore wall surface displacement amounts detected by the displacement sensor 50 (see FIG. 7, displacement sensor 50a) corresponding to the bolt phase (for example, the maximum value or (Minimum value) or average value, and any one of bore wall displacements detected by a displacement sensor (see FIG. 7, displacement sensor 50b) corresponding to the non-volt phase (for example, maximum value or minimum value) or average value The difference value is used as the detection value. Then, a detection signal based on the detected value and an input signal based on the target value are compared and calculated, and a signal based on the difference between the target value and the detected value (control signal for the electromagnetic switching valve 37) is generated. Is done.

  As described above, in the processing jig of the present embodiment, the feedback control unit 60 detects the bore wall surface displacement amount by the target value set in advance according to the target deformation and the displacement sensor 50 with respect to the bore wall surface displacement amount. By performing feedback control based on the difference by comparison with the detection value obtained by this, the adjustment amount of the magnitude of the deformation load by the configuration having the electromagnetic switching valve 37 is controlled. In the present embodiment, the feedback control unit 60 sets the hydraulic pressure supplied to the hydraulic chamber 36 as a control target for feedback control.

  The processing method of this embodiment is demonstrated using the flowchart shown in FIG. In the machining method of the present embodiment, first, the cylinder block 1 as a workpiece is set in equipment (S110). That is, the cylinder block 1 is fixed in a state where the cylinder block 1 is positioned at a predetermined position with respect to the work support surface 57a of the equipment table 57 in such a posture that the head mounting surface 3 side is on the upper side and the bore axis direction is the vertical direction. The

  Next, the working hydraulic pressure of the sensor piston 51 is turned on (S120). That is, the operating hydraulic pressure is supplied to the hydraulic cylinder mechanism 56 that supports the sensor piston 51 so as to be movable up and down. Subsequently, the sensor piston 51 rises (S130). That is, the sensor piston 51 is raised by the hydraulic cylinder mechanism 56 and inserted into the cylinder bore 4 of the cylinder block 1. Here, the sensor piston 51 is supported so that the displacement sensor 50 to be supported corresponds to the direction of the bolt phase in the cylinder block 1, the direction parallel to the crankshaft direction, and the direction perpendicular to the crankshaft direction. The

  Next, the position of the sensor piston 51 is fixed (S140). That is, the height position of the sensor piston 51 inserted into the cylinder bore 4 by the hydraulic cylinder mechanism 56, that is, the position of the sensor piston 51 in the bore axial direction is fixed. Here, the sensor piston 51 is fixed, for example, at a position (height position) such that the displacement sensor 50 is at a height position corresponding to the bottom of the water jacket 6 where quaternary deformation is likely to occur as described above. The position of the sensor piston 51 is fixed by positioning the rod portion 56b with respect to the cylinder portion 56a in the hydraulic cylinder mechanism 56. As a result, the displacement sensor 50 is positioned at a position corresponding to a predetermined detection site in the bore axial direction and the bore circumferential direction in the bore wall surface 4a.

  Subsequently, the horn guide 42 is lowered (S150). That is, the horn guide 42 that guides the horn head 41 in the honing process moves in the proximity of the head mounting surface 3 (downward) above the cylinder block 1 and is separated from the head mounting surface 3 by a predetermined distance. Positioned in the state. As a result, the pressing piece 20 is inserted into the water jacket 6 via the piston rod 35 supported by the hydraulic chamber 36 formed in the horn guide 42. That is, as described above, the pressing piece 20 supported by the piston rod 35 is in a posture in which the pressing direction with respect to the bolt phase portion on the outer peripheral surface 15 of the cylinder portion is included in the direction in which the pressing portions 21 and 22 are separated from each other. Is inserted.

  Next, an initial value for the push hydraulic pressure of the piston rod 35, that is, the hydraulic pressure supplied to the hydraulic chamber 36 is input (S160). That is, the initial value is preset for the hydraulic pressure supplied to the hydraulic chamber 36. Specifically, in the feedback control unit 60, a control signal for the electromagnetic switching valve 37 corresponding to the initial value of the hydraulic pressure supplied to the hydraulic chamber 36 is set in advance. Then, a control signal corresponding to the initial value is sent from the feedback control unit 60 to the electromagnetic switching valve 37, whereby the initial hydraulic value is input to the hydraulic chamber 36.

  Thereby, the bore deformation is reproduced (S170). That is, when the hydraulic pressure is supplied to the hydraulic chamber 36 (specifically, the pressure oil is supplied to the descending hydraulic chamber 36a), the piston rod 35 is urged in the pressing direction. As a result, the pressing piece 20 receives a wedge action from the wedge portion 30 and a predetermined portion of the cylinder portion outer peripheral surface 15 is pressed. Such a pressing action becomes a deformation load on the cylinder block 1 and causes bore deformation.

  In the state where bore deformation has occurred, feedback control is performed on the bore wall surface displacement. In such feedback control, the bore wall surface displacement amount for each phase due to the occurrence of bore deformation is measured (S180). That is, for each cylinder bore 4, by eight displacement sensors 50 supported by the sensor piston 51, the bolt phase, the phase corresponding to the direction parallel to the crankshaft direction, and the phase corresponding to the direction perpendicular to the crankshaft direction are set. The amount of displacement of the bore wall surface for each phase is detected.

  For the bore wall surface displacement amount detected by the displacement sensor 50, it is determined whether or not the detected value matches a preset target value (S190). That is, the feedback control unit 60 performs a comparison operation between an input signal based on a preset target value and a detection signal based on a detection value by the displacement sensor 50, and whether or not the detection value matches the target value. A determination is made.

  If it is not determined in step S190 that the detected value of the bore wall surface displacement amount matches the target value, a correction value for the piston rod 35 hydraulic pressure (hydraulic pressure supplied to the hydraulic chamber 36) is input ( S200). That is, a signal based on the difference between the target value and the detected value generated as a comparison calculation result in the feedback control unit 60 is a control signal corresponding to the correction value. That is, the hydraulic pressure correction value is input to the hydraulic chamber 36 by sending a control signal corresponding to the correction value to the electromagnetic switching valve 37. Thereby, the pressing force (deformation load) with respect to the cylinder part outer peripheral surface 15 by the pressing piece 20 via the piston rod 35 is corrected.

  The measurement of the bore wall surface displacement amount, the comparison between the detected value of the bore wall surface displacement amount and the target value, and the correction of the deformation load are performed until the detected value of the bore wall surface displacement amount matches the target value. When it is determined in step S190 that the detected value of the bore wall surface displacement amount matches the target value, the sensor piston 51 is lowered (S210). That is, in this case, the deformation load applied to the cylinder block 1 becomes a deformation load corresponding to the target deformation, and the application of the deformation load to the cylinder block 1 is completed. Accordingly, the sensor piston 51 is lowered by the hydraulic cylinder mechanism 56 and moves out of the cylinder bore 4.

  In this manner, honing is performed in a state where the target deformation is applied to the cylinder bore 4 by the deformation load. That is, the horn head 41 is lowered and inserted into the cylinder bore 4 through the guide hole 42a of the horn guide 42 in a positioned state (S220). Then, the bore wall surface 4a is ground by the grindstone 43, that is, the honing is performed by the rotational movement of the horn head 41 (S230).

  As described above, in the machining method according to the present embodiment, the deformation load is applied to the cylinder bore 4 with respect to the cylinder block 1 and feedback control is performed on the bore wall surface displacement amount. The amount of adjustment is controlled. In the present embodiment, the deformation load applied to the cylinder bore 4 is a pressing force on a predetermined portion of the cylinder portion outer peripheral surface 15. For this pressing force, the pressing piece 20, the piston rod 35, and the horn guide 42 are used, and the piston rod 35 is urged in the pressing direction by the hydraulic pressure supplied to the hydraulic chamber 36 formed in the horn guide 42. Thus, the pressing piece 20 having a posture in which the pressing direction with respect to the predetermined portion is included in the direction in which the pressing piece 20 spreads (the direction in which the pressing portions 21 and 22 are separated from each other) is applied by applying a wedge action. The hydraulic pressure supplied to the hydraulic chamber 36 is a control target of feedback control.

  According to the machining method and machining jig of the present embodiment described above, the bore deformation that occurs when the engine is operating with respect to the cylinder bore 4 is canceled out by finishing the cylinder bore 4 regardless of the variation in the shape of the cylinder block 1. Deformation (reverse deformation) can be applied, and a decrease in the roundness of the cylinder bore 4 during engine operation can be suppressed.

  That is, when the bore deformation is applied by applying a deformation load to the cylinder block 1, the bore wall surface displacement for each phase of the cylinder bore 4 is performed by performing feedback control for the bore wall surface displacement amount at each phase of the cylinder bore 4. The amount can be a desired value. Thereby, for example, even when the thickness of the cylinder portion 5 is different for each cylinder block 1 or for each cylinder bore 4 in the same cylinder block 1, the target deformation can be stably reproduced with respect to the cylinder bore 4. can do.

  In the present embodiment, the sensor piston 51 that supports the displacement sensor 50 is inserted from the side opposite to the head mounting surface 3 side (lower side) with respect to the cylinder bore 4, but the insertion direction of the sensor piston 51 with respect to the cylinder bore 4 May be from either top or bottom. That is, the sensor piston 51 may be inserted from the head mounting surface 3 side (upper side) with respect to the cylinder bore 4 similarly to the horn head 41.

  Further, in the present embodiment, the hydraulic pressure for urging the piston rod 35 in the pressing direction is used as the load for applying the wedge action to the pressing piece 20, but the present invention is not limited to this. As a load for applying a wedge action to the pressing piece 20, for example, a driving force by a motor may be used. In this case, for example, a configuration is adopted in which a rod member having a wedge portion 30 such as a piston rod 35 is provided so as to be movable in the vertical direction by a ball screw mechanism that is operated by a driving force of an electric motor. That is, in this case, the rotational driving force of the electric motor is converted into vertical linear power by the ball screw mechanism, and this linear power is transmitted as a load for applying a wedge action to the pressing piece 20 via the rod member. The In this case, the driving force by the motor becomes a control target of feedback control for the bore wall surface displacement amount.

  A second embodiment of the present invention will be described with reference to FIGS. 11 corresponds to a cross-sectional view taken along the line BB in FIG. Moreover, in each embodiment shown below, about the part which is common in embodiment already demonstrated, description is abbreviate | omitted suitably using the same code | symbol etc., and a different part from already demonstrated embodiment is demonstrated.

  In the processing method of this embodiment, when detecting the displacement of the bore wall surface by the displacement sensor 50, the cleaning liquid is discharged to the bore wall surface 4a in the process of inserting the sensor piston 71 into the cylinder bore 4. Here, the cleaning liquid is discharged from a position on the front side of the sensor piston 71 in the insertion direction of the sensor piston 71 (hereinafter simply referred to as “front side in the insertion direction”) with respect to the displacement sensor 50 of the sensor piston 71.

  As described above, in order to discharge the cleaning liquid to the bore wall surface 4a, the processing jig of this embodiment has the following configuration. That is, as shown in FIGS. 10 and 11, the sensor piston 71 of the present embodiment has a discharge passage 58 for discharging the cleaning liquid to the bore wall surface 4a.

  Specifically, the discharge passage 58 has an inlet passage portion 58a and an outlet passage portion 58b. The inlet passage portion 58a opens on the lower surface of the sensor piston 71 (the rear side in the insertion direction with respect to the cylinder bore 4, the lower side in FIG. 11) and is parallel to the cylinder axis direction of the sensor piston 71 (up and down in FIG. 11). Direction). The inlet passage 58 a is formed by drilling a hole from the lower surface of the sensor piston 71 in a direction parallel to the cylinder axis direction of the sensor piston 71.

  The outlet passage portion 58b is a linear hole that opens on the upper surface of the sensor piston 71 (front side in the insertion direction with respect to the cylinder bore 4, upper side in FIG. 11) and communicates with the inlet passage portion 58a. The outlet passage portion 58b is formed so as to open obliquely upward outward in the radial direction of the sensor piston 71 from the side communicating with the inlet passage portion 58a. The outlet passage portion 58b opens to a slope portion 51d formed at the peripheral edge portion on the upper side surface of the sensor piston 71. The slope portion 51d is a tapered portion having a shape (partial shape of a conical surface) that goes down toward the outside in the radial direction of the sensor piston 71. The outlet passage portion 58 b is formed by forming a hole portion obliquely from the inclined surface portion 51 d on the upper side surface of the sensor piston 71 toward the radially inner side of the sensor piston 71.

  As shown in FIG. 10, in the present embodiment, eight discharge passages 58 are provided at substantially equal intervals in the circumferential direction of the sensor piston 71. Specifically, the discharge passage 58 is provided between the adjacent displacement sensors 50 with respect to the eight displacement sensors 50 supported by the sensor piston 71 with respect to the circumferential position. The inlet passage portions 58a constituting the discharge passages 58 are formed relatively inside (center axis side) in the sensor piston 71, and the outlet passage portion 58b extends from each inlet passage portion 58a to the diameter of the sensor piston 71. It is formed on the outside in the direction obliquely upward.

  Thus, in the discharge passage 58 formed in the sensor piston 71, the cleaning liquid introduced from the inlet passage portion 58a side is discharged from the outlet passage portion 58b side. Accordingly, a cleaning liquid supply pipe is connected to the opening of the inlet passage 58a located on the lower surface of the sensor piston 71 (not shown). Then, for example, the cleaning liquid stored in the tank or the like is pumped by a pump or the like and introduced into the inlet passage portion 58a via the supply pipe (see arrow B1). The cleaning liquid used here is not particularly limited. As the cleaning liquid, for example, a coolant generally used in aluminum machining is used.

  The cleaning liquid introduced into the inlet passage portion 58a is discharged from the opening portion of the outlet passage portion 58b located on the slope portion 51d on the upper surface of the sensor piston 71 by the outlet passage portion 58b (see arrow B2). Here, the cleaning liquid is discharged with a momentum that reaches at least the bore wall surface 4a. And as above-mentioned, the washing | cleaning liquid discharged from the opening part of the exit channel | path part 58b is discharged radially upwards by the discharge channel | path 58 provided in eight places. As a result, the cleaning liquid discharged from the sensor piston 71 inserted into the cylinder bore 4 uniformly hits the bore wall surface 4a in the circumferential direction.

  As described above, according to the discharge passage 58 formed in the sensor piston 71, the cleaning liquid is discharged from a position on the front side (upper side) in the insertion direction with respect to the displacement sensor 50 in the sensor piston 71. That is, in the sensor piston 71, the displacement sensor 50 is supported by a support hole 51b (see FIG. 8) formed in the lower portion of the sensor piston 71 (in FIG. 11, a straight line SP indicating the height position of the displacement sensor 50). reference). On the other hand, the opening of the outlet passage portion 58b of the discharge passage 58 serving as the discharge port for the cleaning liquid in the sensor piston 71 is formed on the upper side surface (the slope portion 51d) of the sensor piston 71.

  As the sensor piston 71 that discharges the cleaning liquid is inserted into the cylinder bore 4, the cleaning liquid is discharged, so that the deposits such as chips and foreign substances present on the bore wall surface 4a are washed away. Since the cleaning liquid is discharged from a position on the front side in the insertion direction with respect to the displacement sensor 50, in the bore insertion state of the sensor piston 51, from the portion to be measured on the bore wall surface 4a by the displacement sensor 50, chips and the like Deposits are removed.

  Note that air may be used instead of the cleaning liquid in order to remove deposits such as chips present on the bore wall surface 4a. In this case, pressurized air supplied from an air supply source such as an air pump is introduced into the inlet passage portion 58a of the discharge passage 58 via the supply pipe. And the air introduce | transduced into the entrance channel | path part 58a is discharged from the opening part of the exit channel | path part 58b, and is sprayed on the bore wall surface 4a. Thereby, deposits such as chips existing on the bore wall surface 4a are blown off and removed.

  As described above, the sensor piston 71 of the present embodiment has a front side in the insertion direction with respect to the displacement sensor 50 in the sensor piston 71 in the process of insertion of the sensor piston 71 into the cylinder bore 4 when the displacement sensor 50 detects the displacement of the bore wall surface. A discharge passage 58 for discharging the cleaning liquid or air from the position to the bore wall surface 4a.

  In addition, the shape of the discharge passage 58, the position, the number, and the like are not particularly limited as long as the cleaning liquid uniformly hits the bore wall surface 4a in the circumferential direction. The shape of the discharge passage 58 may be, for example, a linear hole penetrating diagonally upward radially outward from the lower surface to the upper surface of the sensor piston 71.

  As shown in FIG. 11, the sensor piston 71 of the present embodiment has a drain hole 59 that forms a discharge passage for the cleaning liquid discharged from the discharge passage 58 and applied to the bore wall surface 4a. The drain hole 59 is a linear hole that opens in the lower surface of the sensor piston 71 and communicates with the outer peripheral groove 51 c into which the sealing material 54 is fitted. The drain hole 59 is formed by drilling a hole from the lower surface of the sensor piston 71 in a direction parallel to the cylinder axis direction of the sensor piston 71.

  The drain hole 59 communicates with the outer circumferential groove 51c by opening it at a position that is not blocked by the sealing material 54 fitted into the outer circumferential groove 51c. Therefore, in the outer circumferential groove 51c, a gap (a space where the sealing material 54 does not exist) is provided inside the sealing material 54 (on the center axis side of the sensor piston 71) allowing the drain hole 59 to open to the outer circumferential groove 51c. . For example, the drain holes 59 are provided at eight locations at substantially equal intervals in the circumferential direction of the sensor piston 71 as in the case of the discharge passage 58. However, the shape of the drain hole 59, the position, the number, etc. of the drain hole 59 are not particularly limited.

  In this way, by providing the drain hole 59 in the sensor piston 71, the cleaning liquid discharged from the discharge port of the discharge passage 58 (opening portion of the outlet passage portion 58b) and flowing down through the bore wall surface 4a and the like flows into the bore wall surface 4a. While being blocked by the sealing material 54 that is in close contact, it is guided into the outer peripheral groove 51c into which the sealing material 54 is fitted. Therefore, in the outer circumferential groove 51c, a gap (a space where the sealing material 54 does not exist) is provided on the upper side (front side in the insertion direction) of the sealing material 54 to allow the cleaning liquid to flow into the outer circumferential groove 51c.

  The cleaning liquid that has flowed into the outer peripheral groove 51c is discharged from the lower surface of the sensor piston 71 through the drain hole 59 (see arrow B3). Thus, in the sensor piston 71, the outer peripheral groove 51c and the drain hole 59 constitute a discharge passage for the cleaning liquid. Here, since the sealing material 54 that blocks the cleaning liquid is located above the displacement sensor 50 (front side in the insertion direction), the adhering material washed away by the cleaning liquid is prevented from entering the displacement sensor 50. That is, the cleaning liquid discharged from the discharge passage 58 and cleaning the bore wall surface 4a is prevented from entering the displacement sensor 50 by the sealing material 54, and discharged together with the washed-out deposits through the outer peripheral groove 51c and the drain hole 59. Is done.

  The processing method of this embodiment is demonstrated using the flowchart shown in FIG. In the processing method of the present embodiment, a step of discharging the cleaning liquid is added to the steps performed in the processing method of the first embodiment.

  The cleaning liquid is discharged when the sensor piston 71 is inserted into the cylinder bore 4. That is, the sensor piston 71 rises while applying the cleaning liquid to the bore wall surface 4a. Then, after the position of the sensor piston 71 is fixed, the discharge of the cleaning liquid is stopped.

  Therefore, after the hydraulic pressure of the sensor piston 71 is turned on (S120), the discharge of the cleaning liquid is started (S125). Then, after the sensor piston 71 is lifted and inserted into the cylinder bore 4 (S130) and the position of the sensor piston 71 is fixed (S140), the discharge of the cleaning liquid is stopped (S145). In this way, the cleaning liquid continues to be discharged after the sensor piston 71 is inserted into the cylinder bore 4 until the position (height position) is fixed. Other steps are the same as the processing method of the first embodiment.

  According to the processing method and the processing jig of the present embodiment, it is possible to effectively prevent erroneous detection due to the deposits present on the bore wall surface 4a for the displacement sensor 50 that detects the bore wall surface displacement amount. Detection accuracy can be improved. Thereby, the stability of the target deformation reproduced in the cylinder bore 4 can be improved.

  A third embodiment of the present invention will be described with reference to FIGS. In the processing method of the present embodiment, the sensor piston 81 is rotatably provided with the bore axis direction as the rotation axis direction. Thus, since the sensor piston 81 is rotatably provided, the processing jig of the present embodiment is provided with a rotation mechanism that allows the sensor piston 81 to rotate with the bore axis direction as the rotation axis direction.

  An example of a rotation mechanism for rotating the sensor piston 81 will be described. The sensor piston 81 is provided to be rotatable with respect to the rod portion 56b of the hydraulic cylinder mechanism 56 (see FIG. 1) that supports the sensor piston 81. That is, the sensor piston 81 is supported on the rotation side with respect to the hydraulic cylinder mechanism 56 on the fixed side.

  As shown in FIGS. 13 and 14, the processing jig of the present embodiment includes a configuration having a rotation mechanism portion 82 and a switching valve 87 as a rotation mechanism for rotating the sensor piston 81. The rotation mechanism part 82 supports the sensor piston 81 so as to be rotatable with respect to the rod part 56b. The rotation mechanism portion 82 is configured to be interposed between the rod portion 56 b and the sensor piston 81.

  The rotation mechanism portion 82 includes a support shaft portion 83 and a housing portion 84. The support shaft portion 83 constitutes a fixed portion in the rotation mechanism portion 82 and is provided at the upper end portion of the rod portion 56b. The support shaft portion 83 is provided by fixing a member different from the rod portion 56b to the rod portion 56b or by integrally forming the rod portion 56b. The support shaft portion 83 has a substantially cylindrical shape (substantially disc shape), and is provided such that the central axis thereof coincides with the rod portion 56 b and the sensor piston 81.

  The housing portion 84 constitutes a rotating portion in the rotating mechanism portion 82 and is provided on the lower surface of the sensor piston 81 (the main body portion thereof). The housing part 84 is provided by fixing a member different from the sensor piston 81 to the sensor piston 81 or by forming it integrally with the sensor piston 81. The housing portion 84 has a substantially cylindrical shape, and is provided such that the central axis thereof coincides with the rod portion 56 b and the sensor piston 81. The housing portion 84 includes a support shaft portion 83 therein.

  That is, the support shaft portion 83 and the housing portion 84 are arranged concentrically with each other, and are provided to be relatively rotatable with the support shaft portion 83 being housed in the housing portion 84. That is, the housing portion 84 is rotatably provided with respect to the support shaft portion 83 on the fixed side.

  The rotation mechanism unit 82 obtains a rotational driving force by hydraulic pressure. For this reason, an operating hydraulic pressure chamber for rotating the housing portion 84 is formed between the support shaft portion 83 and the housing portion 84. In other words, the surface forming the working hydraulic chamber includes the outer peripheral surface of the support shaft portion 83 and the inner peripheral surface of the housing portion 84.

  Specifically, as shown in FIG. 14, the working hydraulic chamber formed between the support shaft portion 83 and the housing portion 84 is directed radially outward at a position facing the outer peripheral surface of the support shaft portion 83. A pair of partition walls (hereinafter, referred to as “fixed-side partition walls”) 83a and a pair of partition walls (hereinafter referred to as “the partition walls”) that are formed to protrude radially inward at positions facing each other on the inner peripheral surface of the housing portion 84. Four hydraulic chambers 85a, 85b, 85c, and 85d that are partitioned by the rotation side partition wall 84a are formed.

  The housing portion 84 is urged with respect to the support shaft portion 83 in one rotation direction (see arrow C1) within a predetermined rotation range by an urging member 86 such as a spring housed in the working hydraulic chamber. In this example, as shown in FIG. 14, the urging member 86 is housed in a pair of opposing hydraulic chambers 85b and 85d among the four hydraulic chambers partitioned as described above. That is, the urging member 86 is interposed between the fixed-side partition wall 83a and the rotation-side partition wall 84a, and presses the partition walls 83a and 84a in a direction in which they are separated from each other.

  In the rotation mechanism section 82 having such a configuration, pressure oil is supplied to a hydraulic chamber (hydraulic chamber 85a and hydraulic chamber 85c, hereinafter referred to as “first hydraulic chamber”) in which the urging member 86 is not provided. When the hydraulic oil is discharged from the hydraulic chamber (hydraulic chamber 85b and hydraulic chamber 85d, hereinafter referred to as “second hydraulic chamber”) in which the urging member 86 is housed, the housing portion 84 is urged by the urging member 86. Against the urging force caused by the urging member 86, the urging member 86 rotates in the direction opposite to the direction of rotation (see arrow C2).

  And as a rotation range of the housing part 84, a predetermined angle range is set between the following states. That is, no pressure oil is supplied to the first hydraulic chamber, and the biasing force of the biasing member 86 causes a predetermined interval between the fixed partition wall 83a and the rotary partition wall 83b that form the second hydraulic chamber. When the housing portion 84 is rotated by the pressure oil being supplied to the first hydraulic chamber, the fixed partition wall 83a and the rotary partition wall 83b that form the second hydraulic chamber are the most. It is the rotation range of the housing part 84 until it approaches. For example, the housing portion 84 is provided so as to be rotatable at least within an angular range of ± 90 ° from a predetermined reference position (0 °).

  Supply and discharge of pressure oil to and from the working hydraulic chamber of the rotation mechanism portion 82 are performed by a switching valve 87. The switching valve 87 is configured as a solenoid operation switching valve, for example. The switching valve 87 adjusts the supply of pressure oil to the first hydraulic chamber and the discharge of hydraulic oil from the second hydraulic chamber (switching of the flow path and adjusting the oil amount).

  In other words, oil in an oil tank (not shown) is supplied to the working hydraulic chamber of the rotating mechanism 82 by the hydraulic pump 88, and adjustment of supply of pressure oil to the working hydraulic chamber is performed by the switching valve 87. Is called. Specifically, the switching valve 87 includes a port that receives oil supply from the hydraulic pump 88, a port connected to the first hydraulic chamber, a port connected to the second hydraulic chamber, and other drains. Port. A port that receives supply of oil from the hydraulic pump 88 is connected to the oil tank via the hydraulic pump 88. The port connected to the first hydraulic chamber is connected to the oil inlet / outlet of the first hydraulic chamber via the oil passage 89a, and the port connected to the second hydraulic chamber is connected to the oil passage 89b. To the oil inlet / outlet port of the second hydraulic chamber. With such a hydraulic circuit configuration, the rotation direction and the rotation amount of the housing portion 84 are adjusted.

  As described above, in the present embodiment, the sensor piston 81 is rotatably provided by the configuration including the rotation mechanism unit 82 and the switching valve 87. Thus, by providing the sensor piston 81 to be rotatable, the number of the displacement sensors 50 can be reduced. That is, the rotation of the sensor piston 81 housed in the cylinder bore 4 allows the displacement sensor 50 to be shared for a plurality of phases in which the bore wall surface displacement amount is detected, so the number of the displacement sensors 50 is reduced. can do. Thus, the cost can be reduced by the amount that the number of the displacement sensors 50 can be reduced.

  Therefore, as shown in FIG. 15, the sensor piston 81 of the present embodiment is provided with a pair of displacement sensors 50 that are disposed to face each other in the radial direction of the sensor piston 81. Then, when the sensor piston 81 is rotated within a predetermined rotation range, the bore wall surface displacement amount in the direction of the bolt phase, the direction parallel to the crankshaft direction, and the direction perpendicular to the crankshaft direction is detected.

  In addition, the rotation mechanism for rotating the sensor piston 81 is not limited to this embodiment. For example, in the rotation mechanism unit 82 as described above, a configuration in which a rotational driving force can be obtained by air pressure may be employed. Further, the sensor piston 81 may be provided to be rotatable by using a rotation driving means such as a motor. In this case, one displacement sensor 50 can be provided.

  By the way, in the cylinder block 1, from the viewpoint of reducing the size of the engine, the interval between the adjacent cylinder bores 4 (dimension between bores, see C3 in FIG. 16) is reduced. In such a cylinder block 1, as shown in FIG. 16, the main bearing portion 7 for supporting the crankshaft (see the straight line CL indicating the axial direction) in the bottom view (bottom view) of the cylinder block 1, There is a case where it interferes with the circumferential shape of the cylinder bore 4.

  Here, the main bearing portion 7 is referred to as a bulk head or the like, and is a wall-like portion provided between the cylinders in the cylinder block 1, and has a shaft hole that supports the crank shaft together with a cap member referred to as a crank cap or the like. Form. That is, the main bearing portion 7 has a semicircular bearing surface 7a, and the cap member also has a semicircular bearing surface corresponding to the bearing surface 7a. And a cap member is fixed to the main bearing part 7 with a volt | bolt etc., and the shaft hole as a bearing part is formed by the semicircular bearing surfaces which both have. The crankshaft is supported by the crank journal (main shaft portion) of the crankshaft being supported in the shaft hole via a bearing.

  Thus, when the main bearing portion 7 interferes with the circumferential shape of the cylinder bore 4 in the cylinder block 1, the piston member (sensor piston) having a substantially cylindrical outer shape corresponding to the cylinder bore 4 is The cylinder block 1 cannot be inserted from below. That is, when the main bearing portion 7 does not secure at least a cylindrical space corresponding to the cylinder bore 4 below the cylinder block 1, a piston member (sensor piston) having a substantially cylindrical outer shape corresponding to the cylinder bore 4 is provided. Interference with the cylinder block 1 (main bearing portion 7) prevents the insertion into the cylinder bore 4.

  Therefore, in the present embodiment, the sensor piston 81 is provided with an escape shape portion 81a for avoiding interference of the sensor piston 81 with the cylinder block 1 when the sensor piston 81 is inserted into the cylinder bore 4.

  Specifically, as shown in FIG. 15, in the sensor piston 81 of the present embodiment, a pair of both sides facing each other in the axial direction of the sensor piston 81 on the outer peripheral surface portion of the sensor piston 81 as the relief shape portion 81 a. A flat portion 81b that is parallel to each other is provided in the portion. That is, the relief shape portion 81a is a shape portion in which portions facing each other in the radial direction with respect to the cylindrical surface shape (see the two-dot chain line) including the outer shape of the sensor piston 81 are cut out in a planar shape.

  Thus, the relief shape portion 81a of the sensor piston 81 is a portion for avoiding interference with the main bearing portion 7 when the sensor piston 81 is inserted into the cylinder bore 4 from below as described above. Therefore, the flat surface portion 81 b as the relief shape portion 81 a is formed corresponding to the opposing wall surfaces of the adjacent main bearing portions 7 in the cylinder block 1. When the sensor piston 81 is inserted into the cylinder bore 4 from the lower side of the cylinder block 1, the flat surface portion 81 b as the relief shape portion 81 a extends along the wall surface of the main bearing portion 7 on both sides of the cylinder bore 4 (planar surface). The portion 81b is inserted at an angle at which the opposing direction of the portion 81b is the axial direction of the crankshaft (an angular position in the bore circumferential direction, hereinafter the same). The sensor piston 81 inserted into the cylinder bore 4 is rotated by the rotation mechanism as described above.

  Further, in the configuration having the relief shape portion 81a like the sensor piston 81 of the present embodiment, the displacement sensor 50 is provided at a position other than the relief shape portion 81a. In the present embodiment, as described above, the pair of displacement sensors 50 arranged opposite to each other in the radial direction of the sensor piston 81 has a relief shape portion 81a (a planar portion 81b) as viewed in the axial direction of the sensor piston 81 as shown in FIG. ) Are arranged with the direction perpendicular to the opposite direction (vertical direction in FIG. 15) as the opposite direction.

  According to the sensor piston 81 that supports the pair of displacement sensors 50 arranged in this way, the detection of the bore wall surface displacement amount in each direction (each phase) of the cylinder bore 4 is performed as follows. That is, the bore wall surface displacement amount in the direction perpendicular to the crankshaft direction mainly related to the secondary deformation is detected by the angle at which the sensor piston 81 is inserted into the cylinder bore 4. That is, the angle at which the sensor piston 81 is inserted into the cylinder bore 4 is such that the opposing direction of the flat surface portion 81b (the vertical direction in FIG. 15) is the axial direction of the crankshaft (the horizontal direction in FIG. Therefore, at such an angle, the pair of displacement sensors 50 arranged to face each other corresponds to a direction perpendicular to the crankshaft direction.

  If the angle when the sensor piston 81 is inserted into the cylinder bore 4 is 0 ° (reference position), the bore wall surface displacement amount in the direction of the bolt phase mainly related to the fourth order deformation is The piston 81 is detected at an angle of about ± 45 °. Further, the bore wall surface displacement amount in the direction parallel to the crankshaft direction mainly related to the secondary deformation is detected at an angle of 90 °.

  Further, in the sensor piston 81 of the present embodiment, the sealing material 80 for preventing the adhering matter such as chips existing on the bore wall surface 4a from entering the displacement sensor 50 side is the circumferential direction of the sensor piston 81. It is provided in a range including a portion other than the relief shape portion 81a and including the portion where the displacement sensor 50 is located.

  Specifically, as shown in FIG. 15, for example, the seal member 80 is provided in the sensor piston 81 so as to have an arc shape with respect to a portion other than the relief shape portion 81a. That is, in this case, the sealing material 80 is provided in a state where the sealing material 80 is divided into two portions with respect to the arc-shaped portion (partial shape of the circumferential surface) that is a position facing the radial direction of the sensor piston 81. Therefore, in this case, the outer peripheral groove 81 c into which the sealing material 80 is fitted is also provided at two positions on the sensor piston 81 corresponding to the shape of each sealing material 80.

  According to the processing method and processing jig of the present embodiment, for example, in comparison with a configuration in which the bore wall surface displacement amount at multiple points (eight locations) is measured non-rotatingly, such as the sensor piston 51 of the first embodiment. The sensor piston can be reduced in size, and it is possible to cope with the cylinder block 1 having a relatively small dimension between the bores.

  A fourth embodiment of the present invention will be described with reference to FIGS. In the present embodiment, a so-called dummy head 91 is used as means for applying a deformation load to the cylinder block 1. That is, in this embodiment, the deformation load is a tightening force obtained by fastening the dummy head 91 to the head mounting surface 3. For this reason, the processing jig of the present embodiment is provided with a configuration having a dummy head 91 and a head bolt 92 as deformation load applying means for applying a deformation load to the cylinder block 1.

  The dummy head 91 simulates a cylinder head attached to the cylinder block 1. The head bolt 92 is a fastening member for fastening and fixing the dummy head 91 to the head mounting surface 3 which is a surface to which the cylinder bore 4 is opened and the cylinder head is mounted. That is, the dummy head 91 is attached to the head mounting surface 3 by the head bolt 92 with respect to the cylinder block 1 in the same manner as the cylinder head, and is a processing jig for imparting deformation to the cylinder bore 4. is there. That is, in the processing method of the present embodiment, the finishing process of the cylinder bore 4 is performed in a state where the dummy head 91 is attached to the head mounting surface 3 by the head bolt 92 with a predetermined tightening force (fastening axial force, tightening torque). (Honing) is performed.

  Specifically, the dummy head 91 is assembled by being fastened and fixed to the head mounting surface 3 using the head bolt 92 and the bolt hole 12. As a result, the cylinder block 1 is in a state in which the cylinder bore 4 is deformed.

  The dummy head 91 is configured as a substantially rectangular plate-shaped member having a size corresponding to at least the size of the head mounting surface 3 as a whole. The dummy head 91 has a pressing surface 91 a that is a surface that comes into contact with a predetermined portion of the head mounting surface 3 on the one (lower) plate surface. That is, in a state where the dummy head 91 is attached to the cylinder block 1, the pressing surface 91 a is in contact with a predetermined portion such as the peripheral portion of the cylinder bore 4 on the head attachment surface 3.

  The dummy head 91 has a hole portion 91 b serving as a through hole for allowing finishing work on the cylinder bore 4 at a position corresponding to each cylinder bore 4 in a state of being attached to the cylinder block 1. That is, in a state where the dummy head 91 is attached to the cylinder block 1, the cylinder bore 4 and the hole 91b are in communication with each other, and the horn head 41 is inserted through the hole 91b, and the cylinder bore 4 is finished. Is called. In the present embodiment, since the cylinder block 1 has four cylinder bores 4 arranged in a row, the dummy head 91 has four holes 91 b in an arrangement corresponding to the cylinder bores 4.

  The dummy head 91 has a bolt insertion hole 91c for allowing the head bolt 92 to pass therethrough. The bolt insertion hole 91c is a hole formed in a direction substantially perpendicular to the pressing surface 91a. The head bolt 92 penetrates the dummy head 91 through the bolt insertion hole 91 c and is screwed into the bolt hole 12 provided in the head mounting surface 3.

  The bolt insertion hole 91 c is provided at a position corresponding to the bolt hole 12 provided in the head mounting surface 3 in the dummy head 91. Accordingly, in the present embodiment, four bolt insertion holes 91c are provided at substantially equal intervals around each hole portion 91b, and two bolt insertion holes 91c are shared between adjacent hole portions 91b, A total of ten are provided.

  As described above, in the present embodiment, the deformation load applying means having the dummy head 91 and the head bolt 92 has the dummy head 91 mounted on the head mounting surface 3 by tightening the head bolt 92 as the deformation load. A tightening force obtained by fastening and fixing to is applied.

  As shown in FIG. 17, in the processing jig of the present embodiment, as a deformation load adjusting means for adjusting the magnitude of the deformation load (clamping force by the head bolt 92) applied by the deformation load applying means, A nut runner 93 which is a tightening mechanism for tightening the head bolt 92 when the dummy head 91 is fastened and fixed to the head mounting surface 3 is provided.

  As shown in FIG. 17, the nut runner 93 is a head bolt for fastening and fixing the dummy head 91 attached to the cylinder block 1 that is supported and fixed in a predetermined posture with the head attachment surface 3 side on the equipment base 57. Tighten by rotating 92. The nut runner 93 fastens the head bolt 92 from above the dummy head 91 placed on the head mounting surface 3 of the cylinder block 1 on the equipment table 57.

  The nut runner 93 has a rotating arm 94 that constitutes a rotating portion for rotating the head bolt 92. The rotating arm 94 is provided so as to protrude downward in the nut runner 93. A plurality of (for example, ten) rotating arms 94 are provided corresponding to the arrangement of the bolt holes 12 opening in the head mounting surface 3 in the cylinder block 1 (the arrangement of the bolt insertion holes 91c of the dummy head 91).

  In the rotating arm 94, a socket portion 94 a is formed that fits into a head portion 92 a of a head bolt 92 that passes through the dummy head 91 and is screwed into the bolt hole 12 of the cylinder block 1. The socket part 94a has a fitting part 94b formed as a concave part along the shape of the head part 92a of the head bolt 92. That is, the head bolt 92 is tightened and the like by rotating the socket portion 94a with the fitting portion 94b fitted to the head portion 92a (see arrow D1).

  The nut runner 93 adjusts the tightening force of the head bolt 92 by the rotating arm 94 by receiving a predetermined control signal. That is, in the nut runner 93, the amount of rotation, the magnitude of the rotational torque, and the like of the rotating arm 94 fitted to the head bolt 92 are controlled.

  Thus, in the processing jig of this embodiment, the nut runner 93 is used as a deformation load applying means for adjusting the magnitude of the deformation load applied by the configuration having the dummy head 91 and the head bolt 92.

  As shown in FIG. 17, the processing jig of the present embodiment includes a feedback control unit 90 as a calculation control unit. The feedback control unit 90 controls the amount of adjustment of the magnitude of the deformation load (clamping force by the head bolt 92) by the nut runner 93 by performing feedback control on the bore wall surface displacement amount.

  The feedback control unit 90 performs feedback control on the bore wall surface displacement amount based on a difference between a target value set in advance according to the target deformation and a detection value obtained by detecting the bore wall surface displacement amount. The target value for the feedback control is set and stored in advance in the feedback control unit 90. In addition, a detection value for feedback control is obtained from an output signal from the displacement sensor 50.

  Therefore, the displacement sensor 50 supported by the sensor piston 51 is connected to the feedback control unit 90 via the cable. An output signal from each displacement sensor 50 is input to the feedback control unit 90 via, for example, a sensor amplifier.

  Then, in the feedback control unit 90, an input signal (reference input signal) based on a preset target value and a detection signal (feedback signal) based on a detection value by the displacement sensor 50 are compared, and the calculation result is as follows: A signal based on the difference (deviation) between the target value and the detected value is generated. The signal generated here is an instruction value for the fastening axial force, the tightening torque, and the like, and is sent as a control signal for the nut runner 93 serving as an operation unit for the controlled object. With this control signal, the amount of rotation, the magnitude of the rotational torque, and the like of the rotation arm 94 in the nut runner 93 are controlled. Such control of the nutrunner 93 is performed until the detected value matches the target value.

  As described above, in the processing jig of the present embodiment, the feedback control unit 90 performs feedback control on the bore wall surface displacement amount, thereby reducing the magnitude of the deformation load by the nut runner 93, that is, the tightening force by the head bolt 92. Control the amount of size adjustment. In this embodiment, the feedback control unit 90 uses the tightening force by the head bolt 92 as a control target of feedback control.

  The processing method of this embodiment is performed by the following procedures, for example. That is, after the cylinder block 1 is set on the equipment table 57, the sensor piston 51 that supports the displacement sensor 50 is raised by the hydraulic cylinder mechanism 56, and the position of the sensor piston 51 is fixed. Next, the dummy head 91 is placed on the head mounting surface 3 with the pressing surface 91a in contact with a predetermined portion, and the head bolt 92 is prepared.

  Then, an initial value for the tightening force of the head bolt 92 is input. That is, an initial value is set in advance for the tightening force of the head bolt 92. Specifically, in the feedback control unit 90, a control signal for the nut runner 93 corresponding to an initial value for the tightening force of the head bolt 92 is set in advance. A control signal corresponding to the initial value is sent from the feedback control unit 90 to the nut runner 93, whereby the initial tightening force value is input to the head bolt 92.

  Thereby, the bore deformation is reproduced. That is, when the head bolt 92 is tightened by the nut runner 93, a tightening force by the head bolt 92 including a pressing action against a predetermined portion of the head mounting surface 3 by the pressing surface 91 a acts on the cylinder block 1. Such an action becomes a deformation load on the cylinder block 1, and bore deformation occurs.

  In the state where bore deformation has occurred, feedback control is performed on the bore wall surface displacement. That is, with respect to the bore wall surface displacement amount, the tightening force (deformation load) by the head bolt 92 is corrected based on the difference between the detected value by the displacement sensor 50 and the preset target value. The modification of the deformation load is performed until the detected value of the bore wall surface displacement amount matches the target value, whereby the application of the deformation load to the cylinder block 1 is completed.

  Accordingly, as shown in FIG. 18, the sensor piston 51 is lowered by the hydraulic cylinder mechanism 56 (see arrow D <b> 2) and moves out of the cylinder bore 4. In this manner, honing is performed in a state where the target deformation is applied to the cylinder bore 4 by the deformation load. That is, after the nut runner 93 moves from the upper position of the dummy head 91 to another place, the horn head 41 descends (see arrow D3) and is inserted into the cylinder bore 4 through the hole 91b of the dummy head 91. Then, the bore wall surface 4a is ground by the grindstone 43, that is, honing is performed by the rotational movement of the horn head 41 or the like.

  As described above, the same effect as that of the above-described embodiment can be obtained also by the processing method and the processing jig of the present embodiment in which the dummy head 91 is used.

The figure which shows the structure of the processing jig which concerns on 1st embodiment of this invention. The top view which shows the cylinder block which concerns on 1st embodiment of this invention. Explanatory drawing about the fourth-order deformation | transformation of a cylinder bore. Explanatory drawing about the secondary deformation | transformation of a cylinder bore. Sectional drawing which shows the structure of a pressing top and a wedge part. The figure which shows the provision structure of the deformation | transformation load which concerns on 1st embodiment of this invention. The top view which shows the sensor piston which concerns on 1st embodiment of this invention. The sensor piston and control block diagram which concern on 1st embodiment of this invention. The flowchart which shows the processing method which concerns on 1st embodiment of this invention. The top view which shows the sensor piston which concerns on 2nd embodiment of this invention. Similarly sectional drawing. The flowchart which shows the processing method which concerns on 2nd embodiment of this invention. Sectional drawing which shows the sensor piston which concerns on 2nd embodiment of this invention. The figure which shows the structure of the rotation mechanism of a sensor piston. The top view which shows the sensor piston which concerns on 3rd embodiment of this invention. The bottom view which shows the structure of a cylinder block. The figure which shows the structure of the processing jig which concerns on 4th embodiment of this invention. The figure which shows the state at the time of the finishing process which concerns on 4th embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylinder block 3 Head mounting surface 4 Cylinder bore 5 Cylinder part 15 Cylinder part outer peripheral surface 20 Pressing piece (pressing member)
21 Inner pressing part (pressing part)
22 Outer pressing part (pressing part)
23 Wedge surface 30 Wedge portion 35 Piston rod (pressing member)
36 Hydraulic chamber (fluid pressure chamber)
37 Electromagnetic switching valve (valve mechanism)
41 Horn head (head)
42 Horn guide (fluid pressure chamber forming member, guide part)
43 Grinding wheel 50 Displacement sensor (displacement detection means)
51 Sensor piston (piston member)
58 Discharge passage 60 Feedback control unit (calculation control means)
71 Sensor piston (piston member)
81 Sensor piston (piston member)
81a Relief shape part 82 Rotating mechanism part 87 Switching valve 90 Feedback control part (calculation control means)
91 Dummy head 92 Head bolt (fastening member)
93 Nutrunner (Tightening mechanism)

Claims (14)

Finishing process for obtaining a predetermined roundness of the cylinder bore in a state in which the cylinder bore, which is a cylindrical hole portion in which the piston is slidably mounted, is subjected to a predetermined deformation that makes the cylinder bore non-circular. A cylinder block machining method for performing
While giving a deformation load which is a load for giving the predetermined deformation to the cylinder bore to the cylinder block,
Regarding the amount of displacement in the radial direction of the cylinder bore of the wall surface forming the cylinder bore, a difference by comparison between a target value set in advance according to the predetermined deformation and a detection value obtained by detecting the displacement amount A cylinder block machining method, wherein an amount of adjustment of the magnitude of the deformation load is controlled by performing feedback control based on the feedback control. The displacement amount detecting means for detecting the displacement amount is supported by a piston member that can be inserted into the cylinder bore,
When detecting the displacement amount by the displacement amount detection means, in the process of inserting the piston member into the cylinder bore, from the position in the piston member in the insertion direction of the piston member to the wall surface from the displacement amount detection means. 2. The cylinder block processing method according to claim 1, wherein the cleaning liquid or the air is discharged.   3. The cylinder block machining method according to claim 1, wherein the piston member is rotatably provided with a center axis direction of the cylinder bore as a rotation axis direction. 4.   The escape shape part for avoiding interference with the said cylinder block of the said piston member at the time of insertion with respect to the said cylinder bore of the said piston member is provided in the said piston member as described in any one of Claims 1-3 characterized by the above-mentioned. Cylinder block processing method. The deformation load is a pressing force against a predetermined part on the outer peripheral surface of the cylinder part which is a wall-shaped part forming the cylinder bore,
The pressing force is
A pressing member having a pressing portion connected to be separable from each other and having a wedge surface that receives a wedge action in a direction in which the pressing portions are separated from each other; and a wedge portion that engages with the wedge surface to give the wedge action. And a pressing member provided so as to be biased at least in a direction in which the wedge action is applied to the pressing member by fluid pressure, and the pressing member is movable in a predetermined sliding direction including a direction in which the wedge action is applied. Using a fluid pressure chamber forming member that forms a fluid pressure chamber that supports and applies fluid pressure to the pressing member;
By urging the pressing member in the direction of applying the wedge action by the fluid pressure supplied to the fluid pressure chamber, the pressing member having a posture in which the pressing direction with respect to the predetermined part is included in the separating direction. It works by giving a wedge action,
The cylinder block machining method according to claim 1, wherein the fluid pressure is a control target of the feedback control. The finishing process includes a head portion that has a honing grindstone and moves the cylinder bore so that the grindstone acts on the cylinder bore, and a surface on which the cylinder bore opens and is attached to the cylinder block. Honing is performed using a configuration including a guide portion that is provided so as to be able to move close to and away from a head mounting surface to which the cylinder head is fixed, and guides the head portion,
The cylinder block machining method according to claim 5, wherein the fluid pressure chamber is provided in the guide portion. The deformation load is obtained by tightening and fixing a dummy head simulating a cylinder head attached to the cylinder block with respect to a head attachment surface that is a surface to which the cylinder bore is opened and the cylinder head is attached. Power,
The cylinder block machining method according to any one of claims 1 to 4, wherein the tightening force is a control target of the feedback control. Finishing process for obtaining a predetermined roundness of the cylinder bore in a state in which the cylinder bore, which is a cylindrical hole portion in which the piston is slidably mounted, is subjected to a predetermined deformation that makes the cylinder bore non-circular. A cylinder block processing jig for performing
Deformation load applying means for applying a deformation load that is a load for applying the predetermined deformation to the cylinder bore to the cylinder block;
Deformation load adjusting means for adjusting the magnitude of the deformation load applied by the deformation load applying means;
A displacement amount detecting means for detecting a displacement amount in a radial direction of the cylinder bore of the wall surface forming the cylinder bore;
For the displacement amount, feedback control is performed based on a difference by comparison between a target value set in advance according to the predetermined deformation and a detection value obtained by detecting the displacement amount by the displacement amount detection means. By means of this, calculation control means for controlling the amount of adjustment of the magnitude of the deformation load by the deformation load adjustment means,
A jig for processing a cylinder block, comprising: The displacement amount detecting means is supported by a piston member insertable into the cylinder bore,
When the displacement amount is detected by the displacement amount detection means, the piston member is positioned in the piston member in the insertion direction of the piston member relative to the displacement amount detection means in the process of inserting the piston member into the cylinder bore. A discharge passage for discharging cleaning liquid or air from the wall surface to
The jig for processing a cylinder block according to claim 8, wherein:   10. The cylinder block processing jig according to claim 8, further comprising a rotation mechanism that allows the piston member to rotate with a central axis direction of the cylinder bore as a rotation axis direction. 10. The piston member has a relief shape portion for avoiding interference with the cylinder block during insertion into the cylinder bore.
The cylinder block processing jig according to any one of claims 8 to 10, wherein the jig is used. The deformation load applying means is
A pressing member having a wedge surface that receives a wedge action in a direction in which the pressing portions are separated from each other and that has a pressing portion that is connected to be separated from each other;
A pressing member that has a wedge portion that engages with the wedge surface and applies the wedge action, and is provided so as to be biased in a direction that applies the wedge action to at least the pressing member by fluid pressure;
A fluid pressure chamber forming member for supporting the pressing member so as to be movable in a predetermined sliding direction including a direction for applying the wedge action and forming a fluid pressure chamber for applying a fluid pressure to the pressing member. ,
As the deformation load, a direction in which the pressing member applies the wedge action to a predetermined portion of the outer peripheral surface of the cylinder portion which is a wall-shaped portion forming the cylinder bore by the fluid pressure supplied to the fluid pressure chamber. By being urged, the pressing member having a posture in which the pressing direction with respect to the predetermined part is included in the separating direction acts on the pressing force obtained by receiving the wedge action,
The deformation load adjusting means is
A valve mechanism for adjusting the supply of the fluid pressure to the fluid pressure chamber;
The arithmetic control means includes
The fluid pressure is a control target of the feedback control.
The jig for processing a cylinder block according to any one of claims 8 to 11, wherein the jig is used. The finishing process includes a head portion that has a honing grindstone and moves the cylinder bore so that the grindstone acts on the cylinder bore, and a surface on which the cylinder bore opens and is attached to the cylinder block. Honing is performed using a configuration including a guide portion that is provided so as to be able to move close to and away from a head mounting surface to which the cylinder head is fixed, and guides the head portion,
The fluid pressure chamber forming member is a member constituting the guide portion.
The jig for processing a cylinder block according to claim 12, wherein the jig is used. The deformation load applying means is
A dummy head simulating a cylinder head attached to the cylinder block;
A fastening member for fastening and fixing the dummy head to a head mounting surface which is a surface to which the cylinder bore is opened and the cylinder bore is opened;
As the deformation load, the fastening force is obtained by fastening and fastening the dummy head to the head mounting surface by fastening the fastening member.
The deformation load adjusting means is
A fastening mechanism for fastening the fastening member when fastening the dummy head to the head mounting surface;
The arithmetic control means includes
The tightening force is a control target of the feedback control,
The jig for processing a cylinder block according to any one of claims 8 to 11, wherein the jig is used.

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