JP3974890B2 - Cylinder block cooling structure manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a cooling structure for an engine cylinder block, and more particularly to a method for assembling a spacer to a water jacket in the cooling structure for an engine cylinder block.

  Conventionally, in Japanese Patent Laid-Open No. 2002-266695, a spacer (also referred to as an “insert”) formed separately from a cylinder block is arranged in a water jacket to make the temperature distribution on the cylinder bore wall (water jacket inner wall) uniform. A cylinder block cooling structure is disclosed.

However, when manufacturing the above-described cylinder block cooling structure, there are the following problems.
That is, when an annular integrated spacer used for an open deck cylinder block is assembled to the cylinder block, the operator can insert the spacer into the water jacket while visually confirming it. As shown in FIGS. 10 and 11, when the automatic assembly machine 30P is used for assembly, the spacer 20P and the water jacket inner and outer walls 4P and 5P of the cylinder block 2P are separated due to the tolerance of the assembly machine 30P. It may be difficult to assemble so as not to interfere. In this case, it is necessary to take measures to absorb the tolerance of the assembling machine by widening the gap C between the spacer 20P and the water jacket inner and outer walls 4P and 5P of the cylinder block, but widen the gap between the spacer and the inner and outer walls of the cylinder block. As a result, more engine cooling water flows through the gap, and it may not be possible to prevent overcooling, which is the intended purpose.
JP 2002-266695 A

  The problem to be solved by the present invention is that in the manufacturing method of the cooling structure of the cylinder block in which the spacer is arranged on the water jacket, the assembly performance of the spacer to the water jacket by the automatic assembly machine is improved, and the cylinder bore wall It is a problem that it is difficult to achieve both the prevention of overcooling by reducing the gap between the spacer and the spacer.

  An object of the present invention is to provide a method for manufacturing a cooling structure of a cylinder block in which a spacer is disposed on a water jacket, and to ensure that the spacer can be assembled to the water jacket by an automatic assembling machine and to prevent overcooling of the cylinder bore. An object of the present invention is to provide a method for manufacturing a cooling structure for a cylinder block.

  The present invention for achieving the above object is as follows.

  A manufacturing method of a cooling structure of a cylinder block in which a circumferentially continuous spacer is arranged on a water jacket of the cylinder block, the deformation of the spacer is corrected by a clamp mechanism of an automatic assembly machine, the spacer is held, A method for manufacturing a cooling structure for a cylinder block, wherein the lower end portion of the spacer is inserted into the water jacket in a state where the deformation of the spacer is corrected, and then the clamp mechanism is removed from the spacer and the entire spacer is inserted into the water jacket. .

  According to the manufacturing method of the cooling structure of the cylinder block of the present invention, since there is a step of correcting the deformation of the spacer by the clamp mechanism of the automatic assembly machine, the automatic assembly machine is inserted into the spacer water jacket and assembled. It is also used to correct the deformation of the spacer, and by correcting the deformation of the spacer, the spacer can be used as a water jacket without increasing the gap between the spacer and the inner and outer walls of the water jacket. It becomes possible to insert. By correcting the deformation of the spacer, the assembly of the spacer to the water jacket can be improved, and the clearance between the spacer and the inner and outer walls of the water jacket is kept small to prevent overcooling of the cylinder bore. Can do.

  The manufacturing method of the cooling structure of the cylinder block of the Example of this invention is demonstrated with reference to FIGS.

The manufacturing method of the cooling structure 1 of the cylinder block of the present invention (which may be referred to as a method of assembling the spacer to the water jacket of the cylinder block) is a circumferential direction in the water jacket 10 formed in the cylinder block 2 of the internal combustion engine. The cylinder block cooling structure 1 (the cylinder block cooling structure 1 in FIGS. 8 and 9) in which the continuous spacers 20 (which may be referred to as “inserts” in the meaning of inserts) are arranged.
Engine cooling water flows through the water jacket 10 to cool the cylinder bore wall 4 (water jacket inner wall) to an appropriate temperature. The spacer 20 is inserted into the water jacket 10 to change the flow distribution of the engine cooling water in the water jacket 10 to make the temperature of the cylinder bore wall 4 (water jacket inner wall) uniform in the vertical direction of each cylinder bore 3 and between the cylinders. .

  The internal combustion engine has one or more cylinder bores 3 in the cylinder block 2. A water jacket 10 is formed around the cylinder bore 3. In the illustrated example, a plurality of cylinder bores 3 are provided in parallel with each other. The shaft cores of the plurality of cylinder bores 3 are positioned on a straight line extending in the cylinder block longitudinal direction. The illustrated example shows a case where a plurality of cylinder bores 3 are formed in the cylinder block 2. The axis of the cylinder bore 3 extends in the vertical direction, and in the V-type engine in which the left and right banks are V-shaped, it extends in the diagonally vertical direction.

  In the in-plane direction orthogonal to the axis of the cylinder bore, the water jacket 10 is formed around the cylinder bore 3 so as to surround the plurality of cylinder bores 3 from the outside, and continuously extends in the annular direction around the cylinder bore (extends without breaks). ). In the illustrated example, the water jacket inner wall 4 is a siamese type, and is formed by connecting the water jacket inner walls 4 of each cylinder. Engine cooling water flows through the water jacket 10 to cool the periphery of the cylinder bore 3 and cool the combustion chamber from the outside.

In the in-plane direction orthogonal to the axis of the cylinder bore, the water jacket 10 has a flow path extending in the cylinder block longitudinal direction on both the left and right sides of the cylinder bore row, and a merging portion at both ends of the cylinder block longitudinal direction. The water jacket 10 has an inlet for engine cooling water at one end in the longitudinal direction of the cylinder block, and an outlet for engine cooling water at the other end in the longitudinal direction of the cylinder block.
In a direction parallel to the axis of the cylinder bore, the water jacket 10 is formed on the side of the stroke range of the upper surface of the piston and has substantially the same depth (height) as the stroke range of the upper surface of the piston.

The water jacket 10 is an open deck water jacket that opens upward. The spacer 20 is inserted into the water jacket 10 from the upper opening and fixed.
The water jacket 10 is a space formed between the water jacket inner wall 4 that also serves as the cylinder bore wall 4 and the water jacket outer wall 5. The water jacket 10 is a space that is covered with the cylinder head via the cylinder head gasket with the bottom wall 6. is there.

  The cylinder head gasket sandwiched between the cylinder block 1 and the cylinder head includes a water hole that allows water to flow from the water jacket 10 in the cylinder block to the water jacket in the cylinder head above and in some places above the water jacket 10. Alternatively, an air vent hole (a hole through which air mixed in water is removed upward when the engine coolant is exchanged) is provided. While the engine cooling water flows from the engine cooling water inlet to the engine cooling water outlet, a part of the engine cooling water exits from the water jacket 10 in the cylinder block through the water hole to the water jacket in the cylinder head.

The spacer 20 is made of resin, for example.
The spacer 20 has a shape and a size that can be inserted into the water jacket 10. The spacer 20 extends around the cylinder bore 3 in an in-plane direction orthogonal to the axis of the cylinder bore. The spacer 20 has a height lower than the depth of the water jacket 10 in a direction parallel to the axis of the cylinder bore. The spacer 20 has a thickness smaller than the width of the water jacket 10.

Since the upper part of the cylinder bore wall, that is, the water jacket inner wall 4 receives heat from the explosion and combustion stroke of the engine, the upper part needs to be cooled more strongly than the lower part. For this reason, in the water jacket 10, it is necessary to flow a large amount of engine cooling water to the water jacket upper portion 11, and to flow to the water jacket lower portion 12 and the water jacket middle portion 13 (height direction middle portion) less than the water jacket upper portion 11. is there. For this reason, the spacer 20 is inserted so as to occupy more space in the water jacket lower portion 12 and the water jacket middle portion 13 than in the space in the water jacket upper portion 11. As a result, the temperature of the cylinder bore wall 4 is made uniform in the vertical direction. The water jacket upper part 11 forms a main cooling passage 18.
When it is desired to keep the water jacket inner wall 4 that is the cylinder bore wall warm (when it is desired to suppress overcooling), the inner surface of the spacer 20 is brought into close contact with the outer surface of the water jacket inner wall 4 or the inner surface of the spacer 20 and the outer surface of the water jacket inner wall 4. It is necessary to reduce the gap 19 (cooling passage) between the two.

  When the spacer 20 is assembled to the water jacket 10 by the automatic assembling machine 30, if the gap 19 (cooling passage) between the spacer 20 and the outer surfaces of the water jacket inner and outer walls 4 and 5 is made small, the assembly becomes difficult. When the gap 19 is increased, the cylinder bore is overcooled, and the cylinder bore is insufficiently kept warm.

  In order to solve the problem, in the manufacturing method of the cylinder block cooling structure 1 according to the present invention, the deformation of the spacer 20 is corrected by the clamp mechanism 31 of the automatic assembly machine 30 and the spacer 20 is held. The lower end of the spacer 20 is inserted into the water jacket 10 in a state where the above is corrected, and then the clamp mechanism 31 is removed from the spacer 20 and the entire spacer 20 is put into the water jacket 10.

More specifically, in the manufacturing method of the cylinder block cooling structure 1 according to the present invention, as shown in FIG. 4, the spacer 20 corrects the deformation of the spacer 20 by the clamp mechanism 31 of the automatic assembly machine 30 and holds the spacer 20. A clamping step, a moving step of moving the held spacer 20 to the position just above the water jacket 10 of the cylinder block 2 by the automatic assembling machine 30, and then lowering the clamping mechanism 31 to hold the lower end of the spacer 20 at the water jacket. A spacer tip insertion process for inserting the spacer 20 into the water jacket 10, and then a spacer 20 entire insertion process for removing the clamp mechanism 31 from the spacer 20 and inserting the entire spacer 20 into the water jacket 10. Return the clamping mechanism 31 of the machine 30 to its original position, Prepare for the lamp process. The deformation correction, clamping, and movement of the spacer 20 may be performed simultaneously.
When the clamp mechanism 31 is removed from the spacer 20 and the entire spacer 20 is inserted into the water jacket 10, the spacer 20 is dropped freely or is forcedly inserted by the push rod 40.

FIG. 5 shows an example of deformation correction of the spacer 20.
The example of FIG. 5 shows a case where the spacer deformation in which the annular short-side span of the spacer 20 is shorter than the regular span occurs during molding. In this case, the correction of the deformation of the spacer 20 by the clamp mechanism 31 of the automatic assembling machine 30 is performed so that the annular short span of the spacer 20 is pushed to a normal span.
Contrary to the example of FIG. 5, in the case where the deformation of the spacer in which the annular short span of the spacer 20 is longer than the regular span occurs at the time of molding, the spacer 20 by the clamp mechanism 31 of the automatic assembling machine 30. The deformation is corrected so that the annular short span of the spacer 20 is shortened to a normal span.

The clamping and deformation correction of the spacer 20 in the clamping process can be easily performed by the method shown in FIGS. 1 to 6 or the method shown in FIG.
1 to 6, the clamp seat 21 is formed in advance on the spacer 20, the laterally extending portion 32 of the clamp mechanism 31 is placed below the clamp seat 21, the spacer 20 is lifted, and the clamp mechanism 31. The vertical extending portion 33 is pressed against the clamp seat 21 in the lateral direction (horizontal direction) to correct the deformation of the spacer 20.

  In this case, the outer shape of the clamp seat 21 is rectangular as shown in FIG. 3, and the direction in which the clamp seat 21 of the vertically extending portion 33 of the clamp mechanism 31 is pushed (clamping direction) as shown in FIG. The correction force is applied obliquely to each clamp seat 21 by being directed obliquely outward with respect to the annular short direction, and the direction perpendicular to the annular short direction (F1 in FIG. 3) of the spacer 20 is also applied. (F2 in FIG. 3), the deformation of the spacer 20 can be corrected at the same time. Accordingly, correction in two directions can be performed by pressing in one direction, and the structure of the clamp mechanism 31 can be simplified as compared with the case where pressing mechanisms are provided in both the F1 and F2 directions.

  Further, as shown in FIG. 4, if the clamp mechanism 31 is supported by the automatic assembly machine 30 formed of a robot via the spring 34, the clamp mechanism 31 when an excessive reaction force is applied to the clamp mechanism 31 from the spacer 20. Can escape and an excessive force is applied to the spacer 20 to prevent the spacer 20 from being damaged.

  Further, when the clamp seat 21 is clamped by the clamp mechanism 31, as shown in FIG. 6, two vertical extension portions 32 of the clamp mechanism 31 are vertically spaced apart from the vertical extension portion 33 of the clamp mechanism 31. If the clamp seat 21 is inserted between the two laterally extending portions 32, the clamp seat 21 can be fixed easily and reliably. If the taper 35 whose interval increases as it goes to the tip is provided on the opposing surfaces of the two laterally extending portions 32, the clamp seat 21 can be fixed more reliably.

When the spacer 20 is expanded in the annular short direction of the spacer 20, the clamp seat 21 is provided on the inner peripheral surface of the spacer 20, but when the spacer 20 is contracted in the annular short direction of the spacer 20, the clamp 20 is clamped. The seat 21 is provided on the outer peripheral surface of the spacer 20.
The clamp seat 21 provided integrally with the spacer 20 remains attached to the spacer 20 even after the spacer 20 is inserted into the water jacket 10.

  When the clamping and deformation correction of the spacer 20 in the clamping process are performed by the method shown in FIG. 7, the arc mechanism at the upper end of the spacer 20 is pressed by the clamp mechanism 31 from both sides of the inner and outer circumferences at a plurality of locations. Correct the deformation. In this case, it is not necessary to provide the spacer 20 with the clamp seat 21 in which the spacer side surface protrudes inward and outward. Therefore, compared with the case where the clamp seat 21 is provided, the gap 19 (cooling passage) between the spacer 20 and the water jacket inner wall 4 or the outer wall 5 can be reduced, and the cylinder bore can be kept warm and prevented from being overcooled. Is advantageous.

Next, the operation and effect of the method for manufacturing a cooling structure for a cylinder block according to the present invention will be described.
First, since the step of correcting the deformation of the spacer 20 by the clamp mechanism 31 of the automatic assembly machine 30 is provided, the automatic assembly machine 30 is not used only for insertion and assembly of the spacer 20 into the water jacket 10. It can also be used to correct the deformation of the spacer 20. By correcting the deformation of the spacer 20, the spacer 20 can be inserted into the water jacket 10 without increasing the gap between the spacer 20 and the inner and outer walls 4, 5 of the water jacket. By correcting the deformation of the spacer 20, the assembling property of the spacer 20 to the water jacket 10 can be improved, and by maintaining the gap 19 between the spacer 20 and the inner and outer walls 4, 5 of the water jacket small, Overcooling of the cylinder bore can be prevented.

If the clamp seat 21 is provided integrally with the spacer 20 and is clamped by the clamp mechanism 31, the deformation of the clamp and the spacer 20 can be corrected, the spacer 20 can be lifted, the water jacket can be moved directly above, and the clamp can be released. It can be done easily. In this case, by setting the clamp seat 21 to have a rectangular outer shape, the deformation correction of the spacer 20 in two directions can be easily performed by pushing in one direction.
Further, if the upper portion of the spacer 20 is clamped by the clamp mechanism 31, the gap 19 between the spacer 20 and the water jacket inner and outer walls 4, 5 can be kept small so that the clamp seat 21 is not provided. And overcooling of the cylinder bore can be further prevented.

It is a top view of an example of the spacer used with the manufacturing method of the cooling structure of the cylinder block of this invention. It is AA sectional drawing of FIG. FIG. 2 is an enlarged plan view of a portion B in FIG. 1. It is the side view which showed each process of the manufacturing method of the cooling structure of the cylinder block of this invention in order. It is a top view of a spacer before and after correction of deformation of a spacer in a manufacturing method of a cooling structure of a cylinder block of the present invention. It is a side view of a clamp mechanism with a more reliable clamp. It is a top view in the case of clamping the spacer upper end part of the manufacturing method of the cooling structure of the cylinder block of this invention. It is a top view of the cooling structure of the cylinder block manufactured by the method of this invention. It is sectional drawing of the cooling structure of the cylinder block manufactured by the method of this invention. It is a perspective view of the conventional method of the assembly | attachment to the cylinder block of a spacer. It is sectional drawing of a water jacket and a spacer at the time of assembling a spacer to a cylinder block by the conventional method.

Explanation of symbols

1 Cylinder block cooling structure 2 Cylinder block 3 Cylinder bore 4 Water jacket inner wall (cylinder bore wall)
5 Water jacket outer wall 6 Water jacket bottom wall 10 Water jacket 11 (Water jacket) Upper part 12 (Water jacket) Lower part 13 (Water jacket) Middle part 18 Upper cooling passage 19 Clearance between spacer and water jacket inner and outer walls ( Cooling passage)
20 Spacer 21 Clamp seat 30 Automatic assembly machine 31 Clamp mechanism 32 Lateral extension 33 Vertical extension 34 Spring 35 Taper 40 Push rod

Claims (1)

  A manufacturing method of a cooling structure of a cylinder block in which a circumferentially continuous spacer is arranged on a water jacket of the cylinder block, the deformation of the spacer is corrected by a clamp mechanism of an automatic assembly machine, the spacer is held, A method for manufacturing a cooling structure for a cylinder block, wherein the lower end portion of the spacer is inserted into the water jacket in a state where the deformation of the spacer is corrected, and then the clamp mechanism is removed from the spacer and the entire spacer is inserted into the water jacket. .

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