JP5597101B2 - Work grinding apparatus, work grinding method, engine valve grinding apparatus, and engine valve grinding method - Google Patents

Description

  The present invention relates to a grinding technique for performing rough grinding to finish grinding with the same equipment.

2. Description of the Related Art Conventionally, as a production line for engine valves used in engines such as automobiles, a production line for performing various kinds of processing by arranging a plurality of processing facilities in the order of processes and causing the engine valves to flow in the order of processes has been used. Grinding in this engine valve production line includes grinding of the cotter groove on one end of the engine valve, rough grinding of the umbrella part on the other end, and finish grinding of the face surface. In general, a grinding apparatus provided with a chuck is used (see, for example, Patent Document 1).
According to the above grinding apparatus, both end portions of the engine valve can be processed at the same time, so that the cotter groove grinding and the rough grinding of the umbrella portion can be integrated into one process and the equipment cost can be reduced. However, the grinding apparatus provided with the collet chuck has a problem that the centering accuracy is slightly sweet.

JP 62-47148 A

In recent years, the applicant has proposed a grinding apparatus having a so-called hollow chuck in order to improve centering accuracy. However, in a grinding machine equipped with a hollow chuck, one end of the engine valve is covered, so the grinding of the cotter groove and the rough grinding of the umbrella part cannot be consolidated in the same process, compared with the case where a collet chuck is used. There is a problem that the number of processes in the engine valve production line increases.
This problem can be solved by integrating the rough grinding of the umbrella part and the finish grinding of the face surface in the same process. However, since the face surface is a part of the umbrella portion and cannot be processed at the same time, there is a problem that it is difficult to achieve both production efficiency and processing accuracy.
The problem related to the balance between production efficiency and processing accuracy when performing rough grinding to finish grinding with the same equipment is not limited to engine valve grinding equipment, but also to work grinding equipment such as crankshafts and crankpins. It is common.

  The present invention has been made in view of the above-described circumstances, and a workpiece grinding apparatus and workpiece capable of obtaining a highly accurate finished surface by performing from rough grinding to finish grinding in a short time with the same equipment. An object is to provide a grinding method, an engine valve grinding apparatus, and an engine valve grinding method.

In order to achieve the above object, the present invention provides a workpiece grinding apparatus for gripping a workpiece and grinding a work surface of a workpiece with a grinding wheel, wherein the grinding wheel performs rough grinding on a grinding surface of one grindstone body. equipped to distinguish and finish grinding area for rough grinding area and finish grinding, the rough grinding area is brought into contact with the processing surface, carried out rough grinding of the surface to be processed by a traverse process, the finish grinding region the by traverse machining of rough grinding is provided on a straight line corresponding to a tangential direction of sliding movement, the finishing grinding region is brought into contact with the workpiece surface after the rough grinding embodiment, the surface to be processed by plunging It is characterized by performing finish grinding.

  In the present invention, the grinding surface of one grindstone body is provided with a rough grinding region and a finish grinding region separately. When rough grinding is performed on a work surface of a workpiece, traverse processing is performed using the rough grinding region, and rough grinding is performed. When finish grinding is performed on the machined surface after execution, plunge processing is performed using the finish grinding area provided separately from the rough grinding area. The grinding efficiency can be improved by increasing the speed, and the finish surface accuracy can be prevented from being deteriorated by grinding wheel wear during rough grinding during finish grinding. Therefore, a highly accurate finished surface can be obtained by performing from rough grinding to finish grinding in a short time with the same equipment.

The rough grinding region may be provided wider than the work surface of the workpiece.
During rough grinding, traverse processing can be performed using the entire area of the rough grinding area wider than the work surface of the workpiece, so that wear in the rough grinding area can be suppressed.
The grinding wheel may be an electrodeposition wheel.
A grinding surface having a complicated shape corresponding to a workpiece having a complicated shape can be easily formed, and when the grinding surface is worn, it can be electrodeposited again and reused, so that the cost can be suppressed.
Abrasive grains having different particle diameters may be electrodeposited in the rough grinding region and the finish grinding region.
The grinding efficiency during rough grinding can be further improved, and the finished surface accuracy can be further improved during finish grinding.

The present invention also provides a workpiece grinding method comprising a workpiece surface continuous grinding process in which rough grinding and finish grinding are continuously performed on a workpiece surface of a workpiece with a grinding wheel. of using a grinding wheel having to distinguish and finish grinding area for rough grinding area and finish grinding of performing rough grinding on the grinding surface of the grinding body, it is abutted against the coarse grinding area on the surface to be processed, the traverse processed by performing the rough grinding of the surface to be processed, the said finish grinding area provided in the rough grinding of the traverse processed by the straight line corresponding to a tangential direction of sliding movement, to the workpiece surface after the rough grinding performed by abutment, which comprises carrying out the finish grinding of the surface to be processed by plunging.

  In the present invention, a grinding wheel having a rough grinding region and a finish grinding region separately provided on the grinding surface of one grindstone body is used to bring the rough grinding region into contact with the work surface of the workpiece, and the workpiece is subjected to traverse processing. After the rough grinding of the machined surface, continuously finish grinding of the machined surface by plunge processing by bringing the finish grinding area provided separately from the coarse grinding area into contact with the machined surface after the rough grinding. To implement. Thereby, at the time of rough grinding, it is possible to improve the grinding efficiency by increasing the grinding wheel peripheral speed while suppressing the wear of the grinding wheel, and at the time of finish grinding, it is possible to prevent a decrease in accuracy of the finished surface due to grinding wheel wear during rough grinding. Therefore, it is possible to obtain a highly accurate finished surface by continuously performing rough grinding to finish grinding on the same work surface in a short time with the same equipment.

Further, the present invention provides an engine valve grinding apparatus that grips a stem portion of an engine valve and grinds an umbrella portion of the engine valve with a grinding wheel, wherein the grinding wheel performs rough grinding on a grinding surface of one grindstone body. equipped to distinguish and finish grinding area for grinding area and finish grinding, said rough grinding region is in contact with the valve head, carried out rough grinding of the bevel portion by traversing process, the finish grinding region, the crude the traverse machining grinding provided on a straight line corresponding to a tangential direction of sliding movement, is abutted against said finish grinding area on the face surface of the umbrella portion after the rough grinding embodiment, the face surface of the umbrella portion by plunging The finish grinding is performed.
The grinding wheel is provided with an R-part grinding surface, an outer-periphery-grinding surface, and a face-surface-grinding surface formed in this order so as to conform to the design shapes of the R-portion, outer peripheral portion, and face surface of the umbrella portion. A grinding surface having a shape, wherein the face grinding surface is formed in a surface having the same tangent to the face surface, and the outer circumferential grinding surface is sandwiched between the rough grinding region and the grinding surface. The rough grinding region and the finish grinding region may be sequentially provided in the direction of the tangent so that the finish grinding region is located on the opposite side.

  In the present invention, the grinding surface of one grindstone body is provided with a rough grinding region and a finish grinding region, and when performing rough grinding on the umbrella portion, traverse processing is performed using the rough grinding region, and after the rough grinding is performed. When finish grinding is performed on the face surface of the umbrella part, the plunge process is performed using the finish grinding area provided separately from the rough grinding area. The grinding efficiency can be improved by increasing the speed, and at the time of finish grinding, it is possible to prevent the finish surface accuracy from being lowered due to grinding wheel wear during rough grinding. Therefore, with the same equipment, it is possible to obtain a highly accurate finished face surface by performing rough grinding to finish grinding in a short time on the umbrella part of the engine valve.

Further, the present invention provides an engine valve grinding method including an umbrella part continuous grinding process in which rough grinding and finish grinding are continuously performed with a grinding wheel on an umbrella part of an engine valve. using a grinding wheel having to distinguish and finish grinding area for rough grinding area and finish grinding of performing rough grinding on the grinding surface of the grinding body, it is abutted against the coarse grinding area to the umbrella portion, the traverse machining performing rough grinding of the umbrella portion, abutting the said finish grinding area provided in the rough grinding of the traverse processed by the straight line corresponding to a tangential direction of sliding movement, the face surface of the umbrella portion after the rough grinding performed by, which comprises carrying out the finish grinding of the face surface of the umbrella portion by plunging.

In the present invention, rough grinding of the umbrella part and finish grinding of the face surface can be performed in a short time with the same equipment, so the rough grinding of the umbrella part and the finish grinding of the face surface are integrated into one process. Can do. As a result, the cotter groove grinding process, which uses a hollow chuck to improve the centering accuracy, and the cotter groove grinding, the rough grinding of the umbrella part, and the finish grinding of the face surface, and the hollow chuck are used. It can be performed in two steps, that is, an umbrella portion grinding step in which rough grinding of the umbrella portion and finish grinding of the face surface are integrated.
Therefore, a combined process in which cotter groove grinding and umbrella rough grinding are simultaneously performed using a collet chuck for three types of processing: cotter groove grinding, umbrella rough grinding, and face face finish grinding, and collet chuck Compared with the engine valve production line which is performed in two steps, that is, the face surface finish grinding process using the process, the machining accuracy can be improved while preventing an increase in the number of processes.

  According to the present invention, the grinding surface of one grindstone body is provided with a rough grinding region and a finish grinding region distinguished from each other, and when performing rough grinding on the work surface of the workpiece, traverse processing is performed using the rough grinding region, When performing finish grinding on the work surface after rough grinding, plunge processing is performed using the finish grinding area provided separately from the rough grinding area. The peripheral speed can be increased to improve the grinding efficiency, and at the time of finish grinding, it is possible to prevent deterioration of the finished surface accuracy due to grinding wheel wear during rough grinding. Therefore, a highly accurate finished surface can be obtained by performing from rough grinding to finish grinding in a short time with the same equipment.

It is a figure which shows the external appearance structure of the engine valve grinding apparatus which concerns on this embodiment. It is a principal part enlarged view of an engine valve grinding apparatus. (A) is an enlarged view of the umbrella part of an engine valve, (B) is the principal part enlarged view of an umbrella part. It is a principal part enlarged view of a grinding wheel. It is a figure which shows operation | movement of an engine valve grinding apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, an engine valve grinding device applied to a production line for an engine valve of an automobile engine, particularly a grinding device for grinding an umbrella portion of the engine valve, will be described as one aspect of the workpiece grinding device according to the present invention. To do.

  For example, in an engine valve production line for an automobile engine, a plurality of processing facilities are arranged in the order of processes, and a cotter groove grinding process for grinding a cotter groove, an umbrella part grinding process for grinding an umbrella part, etc. Various processes such as grinding and heat treatment are performed on the stem part and the umbrella part of the engine valve, etc. by flowing in order.

Hereinafter, the engine valve grinding apparatus 3 provided in the umbrella grinding process will be described with reference to FIGS. 1 and 2. The engine valve grinding device 3 includes a processing unit 5 for grinding the engine valve 2 (see FIG. 2), a transport unit (not shown) for transporting the engine valve 2, and a control unit 7 for controlling the engine valve grinding device 3 as a whole. And.
The processing unit 5 includes a base 9, a grindstone unit 11, a workpiece position adjusting unit 13, and a workpiece gripping / rotating unit 15.
The base 9 supports the grindstone unit 11, the workpiece position adjusting unit 13, and the workpiece gripping / rotating unit 15, and is fixed to the floor surface of the umbrella portion grinding process.

The grindstone unit 11 includes a grindstone spindle 17 and a grinding grindstone 19.
The grindstone spindle 17 includes a case body 21 fixed on the base 9, and a main shaft (not shown) that is rotatably supported by the case body 21 and extends in the Z direction in FIG. The main shaft (not shown) rotates around the rotation axis 23 by driving a grindstone drive source (not shown).
The grinding wheel 19 is formed in a substantially disk shape having a grinding surface 25 on the side surface 19A, and is coaxially fixed to a main shaft (not shown). That is, the grinding wheel 19 rotates around the rotation axis 23 by driving a grinding wheel drive source (not shown). In this embodiment, the grinding wheel 19 can be easily formed with a grinding surface 25 having a complicated shape corresponding to the umbrella portion 4 of the engine valve 2 and can be reused even if the grinding surface 25 is worn. A grindstone is used.

  The workpiece position adjusting unit 13 includes a cross slide 27, an X-direction actuator 29, and a Z-direction actuator 31, and adjusts the position of the engine valve 2 by moving the workpiece gripping / rotating unit 15. The cross slide 27 is provided on the base 9, and is configured to be movable in the X direction, that is, the X1 direction or the X2 direction, and the Z direction, that is, the Z1 direction or the Z2 direction in FIG. The X direction actuator 29 moves the cross slide 27 in the X direction, and the Z direction actuator 31 moves the cross slide 27 in the Z direction.

  The workpiece gripping / rotating unit 15 includes a chuck spindle 33 and a chuck 35, and grips and rotates the stem portion 6 of the engine valve 2. The chuck spindle 33 includes a case body 37 fixed on the cross slide 27 and a main shaft 39 that is rotatably supported by the case body 37 and extends in the Z direction in FIG. The main shaft 39 rotates around the rotation axis 41 by driving a chuck driving source (not shown). The chuck 35 is fixed coaxially to the main shaft 39 and rotates around the rotation axis 41 integrally with the main shaft 39 by driving of a chuck drive source (not shown). The chuck 35 is a hollow chuck as shown in FIG. 2 and has improved centering accuracy.

  In the present embodiment, the engine valve grinding device (not shown) provided in the cotter groove grinding step includes a chuck (not shown) similar to the chuck 35. A chuck (not shown) is a hollow chuck that covers the one end of the engine valve 2 and holds the engine valve 2. When the hollow chuck is used, simultaneous machining of both ends of the engine valve 2, for example, grinding of the cotter groove and rough grinding of the umbrella portion 4 cannot be performed at the same time, but compared with the case of using the collet chuck. Centering accuracy can be increased.

  The engine valve grinding apparatus 3 rotates the grinding wheel 19 around the rotation axis 23, grips the stem portion 6 of the engine valve 2 with the chuck 35, rotates it around the rotation axis 41, and operates the workpiece position adjustment unit 13. Then, the position of the engine valve 2 is adjusted, and the umbrella part 4 of the engine valve 2 is ground by bringing the umbrella part 4 of the engine valve 2 into contact with the grinding surface 25 provided on the side surface 19A of the grinding wheel 19.

By the way, the umbrella part 4 of the engine valve 2 has an R part 4A, an outer peripheral part 4B, and a face surface 4C as shown in FIGS. The R portion 4A, the outer peripheral portion 4B, and the face surface 4C are roughly ground and the face surface 4C is finish-ground.
Here, in the present embodiment, the engine valve grinding apparatus 3 performs grinding processing on the umbrella portion 4 of the engine valve 2 described above, that is, rough grinding of the R portion 4A, the outer peripheral portion 4B, and the face surface 4C, and the face surface 4C. The finishing grinding can be performed with one grinding wheel 19.

  More specifically, the side surface 19A of the grinding wheel 19 is provided with a grinding surface 25 having a concave cross section as shown in FIG. The grinding surface 25 includes an R portion grinding surface 25A that is one side surface, an outer peripheral portion grinding surface 25B that is a bottom surface, and a face surface grinding surface 25C that is the other side surface. The R portion grinding surface 25A is formed along the design shape of the R portion 4A and is used for grinding the R portion 4A. The outer peripheral grinding surface 25B is formed along the design shape of the outer peripheral part 4B and is used for outer peripheral grinding. The face grinding surface 25C is formed along the design shape of the face surface 4C, and is used for grinding the face surface 4C.

However, when both rough grinding and finish grinding are performed on the same face grinding surface 25C of one grinding wheel 19, the finish surface accuracy during finish grinding is improved due to wear of the face grinding surface 25C by rough grinding. There is a problem that it is easy to get worse.
Therefore, in this embodiment, in order to ensure the finish surface accuracy, the face grinding surface 25C used for both rough grinding and finish grinding is provided with a region used for rough grinding and a region used for finish grinding being distinguished from each other. It has been.

Specifically, as shown in FIG. 4, the face grinding surface 25C of the grinding wheel 19 includes a rough grinding region 25C1 used only for rough grinding and a finish grinding region 25C2 used only for finish grinding. ing.
In addition, abrasive grains having different particle diameters are electrodeposited on the rough grinding region 25C1 and the finish grinding region 25C2. In this embodiment, the CBN abrasive grains having a large particle size are electrodeposited on the rough grinding region 25C1, thereby improving the grinding efficiency during the rough grinding, and the CBN abrasive particles having a small particle size are electrodeposited on the finish grinding region 25C2. Furthermore, the finishing surface accuracy is improved by performing a process for aligning the tip heights of the abrasive grains.

In the present embodiment, the R portion 4A, the outer peripheral portion 4B, and the face surface 4C can be traversed so that the grinding wheel peripheral speed can be increased to improve the grinding efficiency. Further, the plunge processing can be performed on the face surface 4C so that the finished surface accuracy can be improved.
In this specification, traverse processing refers to a tangential direction between a work surface of a workpiece and a grinding surface of a grindstone, in which the work surface of the workpiece is brought into contact with a grinding surface of the grindstone in a state where both the work and the grindstone are rotated. It is defined as a grinding process in which a workpiece is moved by sliding the workpiece in a direction perpendicular to the workpiece surface while intersecting the tangent line while moving the workpiece.

For example, as shown by a chain line in FIG. 4, in rough machining of the face surface 4C, the face surface 4C is contacted with the face surface grinding surface 25C of the grinding wheel 19 while the engine valve 2 and the grinding wheel 19 are rotated together. The engine valve 2 is moved by the combined operation of the workpiece position adjusting unit 13 in the X2 direction and the Z1 direction.
As a result, the engine valve 2 is slid in the direction of the tangent 45 between the face surface 4C and the face grinding surface 25C (the direction indicated by the arrow 47 in FIG. 4) to feed the workpiece while crossing the tangent 45 and crossing the face. Traverse processing in which cutting is performed by moving the engine valve 2 in a direction perpendicular to the surface 4C (a direction indicated by an arrow 49 in FIG. 4) is possible.

On the other hand, in this specification, plunge machining means that the work surface of the work is brought into contact with the grinding surface of the grindstone while both the work and the grindstone are rotated, and the work surface of the work and the grinding surface of the grindstone are It is defined as a grinding process in which the workpiece is moved in the direction perpendicular to the workpiece surface intersecting with the tangent line without moving the workpiece almost in the tangential direction.
For example, as shown in FIG. 4, in finishing the face surface 4C, the face surface 4C is brought into contact with the grinding surface 25 of the grinding wheel 19 in a state where both the engine valve 2 and the grinding wheel 19 are rotated. The engine valve 2 is moved by the operation of the position adjusting unit 13 in the Z1 direction.
Thus, the engine valve 2 is hardly slid in the direction of the tangent 45 between the face surface 4C and the grinding surface 25 (the direction indicated by the arrow 47 in FIG. 4) and intersects the tangent 45 and is perpendicular to the face surface 4C. Plunge machining is possible in which cutting is performed in any direction (the direction indicated by the arrow 49 in FIG. 4).

In this embodiment, the width L1 of the rough grinding region 25C1 is set to be wider than the maximum width of the face surface 4C, for example, 8 mm so as to suppress wear of the rough grinding region 25C1 due to rough grinding. At the time of grinding, the wide rough grinding region 25C1 can be used for traverse processing.
In the present specification, the maximum width of the face surface 4C is defined as the maximum width among the widths of the face surfaces 4C of a plurality of types of engine valves 2 manufactured on the engine valve manufacturing line.
On the other hand, the width L2 of the finish grinding region 25C2 is set to a width of 4 mm, for example, equivalent to the maximum width of the face surface 4C. As a result, the face surfaces 4C of a plurality of types of engine valves 2 manufactured in the engine valve manufacturing line can be plunge processed using only the finish grinding region 25C2.

  Under the above configuration, the engine valve grinding device 3 provided in the umbrella part grinding step performs rough grinding on the R part 4A, the outer peripheral part 4B, and the face surface 4C of the umbrella part 4 of the engine valve, and the face of the umbrella part 4 The finish grinding of the surface 4C is continuously performed.

Below, operation | movement of the engine valve grinding apparatus 3 is demonstrated.
First, when the engine valve 2 flows from the upstream side of the engine valve production line, the engine valve 2 is transported to the chuck 35 by a transport unit (not shown), and the chuck 6 holds the stem portion 6 of the engine valve 2. To do. At this time, as indicated by a chain line in FIG. 5A, the umbrella portion 4 of the engine valve 2 is separated from the grinding wheel 19.
Next, the grinding wheel 19 is rotated at a high speed by a grindstone driving source (not shown), and the chuck driving source (not shown) is driven to rotate the engine valve 2.

Next, the engine valve 2 is moved in the X1 direction by the workpiece position adjusting unit 13, and the R part 4A of the engine valve 2 is brought into contact with the R part grinding surface 25A of the grinding wheel 19 as indicated by a broken line in FIG. 5A. . At this time, the R portion 4A and the R portion grinding surface 25A abut on the tangent line 51.
Subsequently, the engine position 2 is moved by the workpiece position adjusting unit 13 in the compound direction of the X1 direction and the Z1 direction, and the R portion 4A is roughly ground. Specifically, the engine valve 2 is moved in the direction intersecting the tangent line 51 and perpendicular to the R portion 4A (the direction indicated by the arrow 55 in FIG. 5A) to make a cut, and the direction of the tangential line 51 (the arrow in FIG. 5A). The workpiece is fed to the position indicated by the solid line in FIG. 5A, and the R portion 4A is ground by a predetermined machining allowance.

Subsequently, the work position adjusting unit 13 moves the engine valve 2 to a position indicated by a broken line in FIG. 5B, and brings the outer peripheral portion 4B of the engine valve 2 into contact with the outer peripheral portion grinding surface 25B of the grinding wheel 19. At this time, the outer peripheral portion 4B and the outer peripheral grinding surface 25B abut on the tangent line 52.
Subsequently, the engine position 2 is moved by the workpiece position adjusting unit 13 in the compound direction of the X1 direction and the Z1 direction to perform rough grinding of the outer peripheral portion 4B. That is, the engine valve 2 is moved in a direction (indicated by an arrow 59 in FIG. 5B) that intersects the tangent line 52 and is perpendicular to the outer peripheral portion 4B, and performs a tangential direction (a direction indicated by an arrow 61 in FIG. 5B). The workpiece is fed to reach the position indicated by the solid line in FIG. 5B, and the outer peripheral portion 4B is ground by a predetermined machining allowance. This processing is also the traverse processing described above, and wear of the outer peripheral grinding surface 25B is suppressed even when the cutting depth is large and the peripheral speed of the grinding wheel 19 is high.

Subsequently, the work position adjusting unit 13 moves the engine valve 2 to the position indicated by the broken line in FIG. 5C, so that the face surface 4C of the engine valve 2 comes into contact with the rough grinding region 25C1 of the face grinding surface 25C of the grinding wheel 19. Let At this time, the face surface 4C and the rough grinding region 25C1 abut on the tangent line 53.
Then, the workpiece position adjusting unit 13 moves the engine valve 2 in the combined direction of the X2 direction and the Z1 direction to perform rough grinding of the face surface 4C. That is, the engine valve 2 is moved in the direction intersecting the tangent line 53 and perpendicular to the face surface 4C (the direction indicated by the arrow 63 in FIG. 5C) to make a cut, and the tangential direction (the direction indicated by the arrow 65 in FIG. 5C). To the position indicated by the solid line in FIG. 5C, and the face surface 4C is ground by a predetermined machining allowance. This processing is also the traverse processing described above, and wear of the rough grinding region 25C1 is suppressed even when the cutting depth is large and the peripheral speed of the grinding wheel 19 is high.

Next, after the rotational speed of the engine valve 2 is decreased, the work position adjusting unit 13 moves the engine valve 2 to the position shown by the solid line in FIG. 5D, and the face surface 4C after the rough grinding is performed. It abuts on the finish grinding region 25C2 of 25C. At this time, the face surface 4C and the finish grinding region 25C2 abut on the tangent line 53.
Subsequently, the work position adjusting unit 13 moves the engine valve 2 in the Z1 direction to perform finish grinding of the face surface 4C. That is, the engine valve 2, by moving in the Z1 direction, without causing almost sliding movement in the tangential direction indicated by arrow 6 5 Figure 5D, intersects the tangent 53 face 4C perpendicular direction (in Figure 5D perform incision is moved in direction) indicated by arrow 6 3, grinding the face surface 4C predetermined machining allowances.
This processing is the above-described plunge processing, and the finished surface accuracy is improved by reducing the peripheral speed of the engine valve 2 and reducing the cutting amount.

  Next, the engine position 2 is moved away from the grinding wheel 19 by the workpiece position adjusting unit 13 and moved to the position indicated by the chain line in FIG. 5D. Next, the driving of the chuck drive source (not shown) is stopped, and the rotation of the engine valve 2 is stopped. Then, the engine valve 2 is gripped by a workpiece transfer device (not shown) and the gripping by the chuck 35 is released. The engine valve 2 is removed from the chuck 35 and discharged to the downstream side of the engine valve production line.

  As described above, in this embodiment, one grinding wheel 19 of the engine valve grinding apparatus 3 distinguishes between the rough grinding region 25C1 for rough grinding and the finish grinding region 25C2 for finish grinding on the grinding surface 25. I have. Then, the face surface 4C is brought into contact with the rough grinding region 25C1, the face valve 4C is rough ground by traverse processing while the engine valve 2 is fed in the X and Z directions, and the finish grinding region 25C2 is rough ground. The face surface 4C is brought into contact with the rear face surface 4C, and finish grinding of the face surface 4C is performed by plunge processing while feeding in the Z direction. As a result, when rough grinding of the face surface 4C is performed, the peripheral speed of the grinding wheel 19 can be increased while suppressing the wear of the grinding wheel 19, and the grinding efficiency can be improved. The finish grinding region 25C2 that does not receive the workpiece can be processed with high accuracy. Therefore, the engine valve grinding apparatus 3 having one grinding wheel 19 can perform rough grinding to finish grinding in a short time to obtain a highly accurate finished surface.

Further, in the present embodiment, the rough grinding region 25C1 is provided wider than the face surface 4C of the engine valve 2, and during rough grinding, rough grinding is performed by traverse processing using the entire region of the wide rough grinding region 25C1. Since it performs, abrasion of the rough grinding area | region 25C1 can be suppressed.
Further, in this embodiment, since the grinding wheel 19 is an electrodeposited grinding wheel, a complicated shaped grinding surface 25 corresponding to the umbrella portion 4 of the engine valve 2 can be easily formed. Since it can be worn and reused, costs can be reduced.
Further, in the present embodiment, abrasive grains having a large particle size are electrodeposited in the rough grinding region 25C1, and abrasive particles having a small particle size are electrodeposited in the finish grinding region 25C2, so that the grinding efficiency during rough grinding can be further increased. As well as improving the finish surface accuracy during finish grinding.

Further, in this embodiment, the rough grinding of the umbrella part 4 and the finish grinding of the face surface 4C can be performed in a short time by the same engine valve grinding apparatus 3, so the rough grinding of the umbrella part 4 and the face surface 4C are performed. Can be integrated into one umbrella grinding process. As a result, the cotter groove grinding process in which the centering accuracy is improved by using the hollow chuck, and the three types of processing of the cotter groove grinding, the rough grinding of the umbrella portion 4 and the finish grinding of the face surface 4C are the hollow chuck and the cotter groove grinding process. While using the chuck 35, it is possible to perform the two processes of the umbrella part grinding process in which rough grinding of the umbrella part 4 and finish grinding of the face surface 4C are integrated.
Therefore, a combined process in which the cotter groove grinding, the rough grinding of the umbrella part 4 and the rough grinding of the umbrella part 4 are simultaneously performed using the collet chuck for three types of processing, that is, cotter groove grinding, rough grinding of the umbrella part 4 and finish grinding of the face surface 4C. Compared with the engine valve production line that performs the two steps of the face surface 4C using the collet chuck, the machining accuracy can be improved while preventing an increase in the number of steps and reducing the capital investment.

  The above-described embodiment is merely an aspect of the present invention, and can be arbitrarily modified within the scope of the present invention. For example, in the above-described embodiment, an electrodeposition grindstone is used as the grinding wheel 19, but the type of the grinding wheel 19 is not limited to this. In the above-described embodiment, a configuration in which abrasive grains having a large particle size are electrodeposited in the coarse grinding region 25C1 and abrasive grains having a small particle size are electrodeposited in the finish grinding region 25C2 is exemplified. Abrasive grains having a small particle size may be electrodeposited on 25C1, and abrasive grains having a large particle size may be electrodeposited on finish grinding region 25C2, or abrasive grains having the same particle size may be provided on rough grinding region 25C1 and finish grinding region 25C2. It may be electrodeposited.

  Further, in the above-described embodiment, the configuration in which abrasive grains of the same material, that is, CBN abrasive grains are electrodeposited on the rough grinding region 25C1 and the finish grinding region 25C2 is illustrated. Abrasive grains, silicon carbide-based abrasive grains, diamond abrasive grains, or the like may be used, and abrasive grains of different materials may be electrodeposited in the rough grinding region 25C1 and the finish grinding region 25C2. According to this configuration, even when the material of the engine valve 2 is different, it is possible to perform grinding with high grinding efficiency during rough grinding and to perform grinding accurately with finish grinding.

1 Engine valve production line 2 Engine valve (work)
3 Engine valve grinding equipment (work grinding equipment)
4 Umbrella part (machined surface)
4C face surface 6 stem portion L1 width L2 width 19 grinding wheel 25 grinding surface 25C face surface grinding surface 25C1 rough grinding area 25C2 finish grinding area

Claims (8)

In a workpiece grinding device that grips a workpiece and grinds the workpiece surface with a grinding wheel,
The grinding wheel is provided with distinction between a rough grinding region for rough grinding and a finish grinding region for finish grinding on the grinding surface of one grindstone body,
The rough grinding area is brought into contact with the processing surface, carried out rough grinding of the surface to be processed by a traverse process,
The finish grinding region, said the traverse process of rough grinding is provided on a straight line corresponding to a tangential direction of sliding movement, is abutted against said finish grinding area on the workpiece surface after the rough grinding performed by plunging workpiece grinding machine which comprises carrying out the finish grinding of the surface to be processed.   The workpiece grinding apparatus according to claim 1, wherein the rough grinding region is provided wider than a workpiece surface of the workpiece.   The workpiece grinding apparatus according to claim 1, wherein the grinding wheel is an electrodeposition grindstone.   The workpiece grinding apparatus according to claim 1, wherein abrasive grains having different particle sizes are electrodeposited in the rough grinding region and the finish grinding region. In a workpiece grinding method with a workpiece surface continuous grinding process in which rough grinding and finish grinding are continuously performed on a workpiece surface with a grinding wheel,
Wherein the surface to be processed continuously grinding process using a grinding wheel having to distinguish and finish grinding area for rough grinding area and finish grinding of performing rough grinding on the grinding surface of one grinding body, the said rough grinding area is brought into contact with the processing surface, carried out rough grinding of the surface to be processed by a traverse process,
Wherein said finish grinding area provided in the rough grinding of the traverse processed by the straight line corresponding to a tangential direction of sliding movement, said after rough grinding performed by contacting the treated surface, the surface to be processed by plunging A work grinding method characterized by performing finish grinding. In the engine valve grinding device that grips the stem part of the engine valve and grinds the umbrella part of the engine valve with a grinding wheel,
The grinding wheel is provided with distinction between a rough grinding region for rough grinding and a finish grinding region for finish grinding on the grinding surface of one grindstone body,
Said rough grinding region is in contact with the valve head, carried out rough grinding of the bevel portion by traversing process,
The finish grinding region, said the traverse process of rough grinding is provided on a straight line corresponding to a tangential direction of sliding movement, is abutted against said finish grinding area on the face surface of the umbrella portion after the rough grinding embodiment, plunge machining the engine valve grinding apparatus which comprises carrying out the finish grinding of the face surface of the valve head. The grinding wheel is provided with an R-part grinding surface, an outer-periphery-grinding surface, and a face-surface-grinding surface formed in this order so as to conform to the design shapes of the R-portion, outer peripheral portion, and face surface of the umbrella portion. Having a grinding surface of shape,
  The face grinding surface is formed into a surface having the same tangent to the face surface, and the finish grinding region is opposite to the outer peripheral grinding surface across the rough grinding region with the face grinding surface. The engine valve grinding apparatus according to claim 6, wherein the rough grinding region and the finish grinding region are sequentially provided in the direction of the tangent so as to be positioned. In the engine valve grinding method comprising an umbrella part continuous grinding process in which rough grinding and finish grinding are continuously performed with a grinding wheel on the engine valve umbrella part,
  In the umbrella portion continuous grinding process, the rough grinding region is divided into the umbrella using the grinding wheel provided with a rough grinding region for rough grinding and a finish grinding region for finish grinding on the grinding surface of one grindstone body. The umbrella part is rough ground by traverse processing.
  The umbrella portion is formed by plunge processing by bringing the finish grinding region provided on a straight line corresponding to the tangential direction to be slid by the rough grinding traverse processing into contact with the face surface of the umbrella portion after rough grinding. An engine valve grinding method characterized in that finish grinding of the face surface of the engine is carried out.

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