JP4112471B2 - Processing method and processing apparatus for valve seat surface and valve guide hole of cylinder head - Google Patents

Description

The present invention relates to a machining method及beauty machining apparatus of the valve seat surface and the valve guide bore of a cylinder head.

  The cylinder head of the internal combustion engine is provided with an intake / exhaust valve. The cylinder head is provided with a valve seat, and a cylindrical valve guide is provided concentrically with the valve seat. A valve body that seals the valve seat surface is attached to the valve seat and the valve guide. The valve body includes a stem that is inserted into the valve guide hole and slides along the guide hole, and a flat conical valve head that is connected to the tip of the stem and contacts and separates from the valve seat surface. ing. A valve face provided on the valve head is brought into contact with the valve seat surface with airtightness. The valve seat surface is formed by a seat surface processing tool in a seat surface prepared hole formed in advance in the valve seat. When the valve face is not properly in contact with the valve seat surface, the airtightness in the cylinder is impaired. For this reason, high accuracy is required for the concentricity between the valve guide hole for slidingly guiding the stem and the valve seat surface with which the valve face abuts.

  In order to solve the above problems, a combined machining tool shown in Patent Document 1 has been proposed. This composite machining tool includes a cutter for valve seat surface machining at the tip of a tool body having a tapered portion that engages with a tapered hole formed in a rotating spindle of a machine tool. In addition, the combined machining tool includes a valve guide hole machining reamer capable of moving back and forth in the axial direction with respect to the tool body by the pressure of a coolant supplied to the inside of the tool body via the rotary main shaft. . Further, a blade for pilot hole machining at the time of valve guide hole machining is provided at the tip of the reamer.

A pilot hole that rotates on the same axis with respect to a pilot hole of a valve guide that is formed in advance by a drill or the like, while simultaneously forming a valve seat surface (the contact surface in Patent Document 1) on the valve seat by the cutter of the above-mentioned combined machining tool A pilot hole is formed by a cutting blade. Thereafter, the cutter and the reamer are retracted, the reamer is advanced, and the pilot hole machining blade formed at the tip of the blade is again entered into the pilot hole formed in the valve guide. The following pilot hole is machined to finish the valve guide hole.
JP 2002-126920 A

  In the conventional composite machining tool, the pilot hole is formed concentrically with the valve seat surface because the pilot seat is formed in the pilot guide hole at the same time as the valve seat surface is formed on the valve seat. The For this reason, by first engaging the pilot hole machining blade with the pilot hole, the reamer can be guided along the center axis of the valve guide hole, and the valve guide hole and the seat surface of the valve seat can be guided. The accuracy of concentricity can be improved.

  However, the above-mentioned conventional combined machining tool forms the pilot hole by rotating the pilot hole machining blade to simultaneously contact the entire opening edge of the pilot hole formed in the valve guide, and the following problems arise. It was. When the center axis of the pilot hole formed in the valve guide is in a state of misalignment displaced from the normal center axis, the plurality of pilot hole machining blades start to cut into the opening edge of the pilot hole Since each blade is simultaneously brought into contact with the opening edge, each blade is easily affected by the opening edge in a state of misalignment. That is, since the cutting resistance by each blade varies depending on the circumferential portion of the opening edge, each blade itself is pushed back toward the smaller cutting force and is eccentric, reducing the accuracy of the concentricity of the pilot hole itself with respect to the valve seat surface. To do. As a result, there is a problem that the concentricity cannot be improved even if the tip of the reamer enters the pilot hole with low accuracy of concentricity and finishes the valve guide hole.

  Even if the central axis of the pilot hole formed in the valve guide is on the regular central axis, each blade for pilot hole machining tends to be eccentric when starting cutting into the opening edge of the pilot hole. The accuracy of the pilot hole concentricity is reduced.

The present invention is to provide a processing method及beauty machining apparatus of the valve seat surface and the valve guide bore of a cylinder head that can improve the accuracy of the concentricity of the valve guide holes for the valve seat surface provided in the cylinder head is there.

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a pilot hole processing tool, a rough finishing abrasive reamer, and a finishing abrasive reamer are placed on the same axis at the tip side of the columnar tool body. A sheet formed in advance on the valve seat provided on the cylinder head using a processing tool for the valve seat surface and valve guide hole of the cylinder head provided with a seat surface processing tool at the base end of the tool body. a seat surface forming a valve seat surface and finished by the seat surface processing tool which rotates at the same axis with respect to a plane under the hole, to a preformed guide hole under the hole in the valve guide which is provided in the cylinder head Shirindahe' comprising a valve guide hole forming step of forming a valve guide hole and finishing the rough finishing abrasive reamers and finishing abrasive reamer rotates at the same axis In the valve seat surface and working method of the valve guide hole, wherein prior to the sheet face forming step, the relative seat surface under the hole, the tool tapering portion formed concentrically tip of the pilot drilling tool A rotation and a contouring movement are brought into contact with each other by a rotation and a turning movement of the main body shaft so as to form a tapered portion. Next, prior to the valve guide hole forming step, an opening end side of the guide hole pilot hole is formed. to the inner circumferential surface, a pilot drilling tool digits set on the tip portion of the tool body contacts by rotating and contouring motion by pivoting movement and rotation of the tool body axis, so as to form a pilot hole, the pilot bore Rotating and contouring the taper machining part by rotating and turning the tool body shaft against the inner peripheral corner of the pilot hole machined by the machining tool The tapered guide part is formed, and then the valve guide hole is formed by rough finishing and finishing with the rough finishing abrasive reamer and the finishing abrasive reamer rotating on the same axis with respect to the guide hole pilot hole. After the finishing abrasive reamer passes through the entire length of the valve guide hole and finishes, the seat surface processing tool contacts the tapered portion formed on the valve seat to form the valve seat surface. The summary is as follows.

According to a second aspect of the invention, the support table of the cylinder head which is So設the bed is mounted to the bed, and the distal end of the tool body forming a columnar, pilot drilling tool, roughing abrasive reamer and A finishing abrasive reamer is installed on the same axis in order from the tip side, and a tool for processing the valve seat surface and valve guide hole of the cylinder head, which is provided with a seat surface processing tool at the base end of the tool body, is mounted so that it can be actively rotated. A spindle device, a contouring motion imparting mechanism that is mounted between the bed and the spindle device and that imparts a contouring motion by rotation and turning motion to the spindle of the spindle device, and a support table or the spindle device is moved back and forth. Controls the operation of the longitudinal motion mechanism and the contouring motion imparting mechanism and outputs a control signal for imparting the contouring motion to the machining tool supported by the spindle device And a control signal is output from the control device to apply a contouring motion to the machining tool by orthogonal two-axis feed, and a guide hole prepared in a valve guide provided in the cylinder head is opened. A pilot hole is formed with a pilot hole processing tool provided at the tip of the tool body on the inner peripheral surface on the end side, and the finishing abrasive reamer passes through the entire length of the valve guide hole and finishes finishing. The gist of the invention is that the seat surface processing tool is configured to contact the valve seat to form a valve seat surface .

According to the invention of claim 1 or claim 2, wherein forming the pilot hole to set only pilot drilling tool at the tip of the tool body is rotated and contouring motion to the inner circumferential surface of the guide hole under the hole of the valve guide I tried to do it. For this reason, the contact area of the pilot hole processing tool with respect to the inner peripheral surface of the guide hole pilot hole is reduced, the load resistance during processing work is reduced, and the eccentricity of the pilot hole processing tool itself following the pilot hole is prevented, The accuracy of the concentricity of the pilot hole with respect to the valve seat surface can be improved. Accordingly, the accuracy of the concentricity of the valve guide hole formed by the reamer in the valve guide with respect to the valve seat surface can be improved.

According to the first aspect of the present invention, prior to the processing of the valve seat surface by the seat surface processing tool, the tapered portion is applied to the seat surface pilot hole, and the allowance at the time of finishing processing is the seat width. Taper processing was performed by rotation and contouring motion so as to be uniform. For this reason, at the time of finishing the valve seat surface by the seat surface processing tool, uneven wear of the tool is eliminated, the tool life is greatly extended, and the accuracy can be improved. Further, the taper machining portion formed at the tip portion of the pilot hole machining tool is applied to the inner peripheral corner of the opening edge of the pilot hole, and is chamfered by rotating and contouring. For this reason, when the tip of the reamer is inserted into the pilot hole, there is no contact with burrs or tips, smooth operation is possible, tool wear is reduced, tool life is extended, and valve guide holes are processed more appropriately. And the accuracy of the concentricity can be further improved.

Furthermore, according to the first or second aspect of the invention, since the reamer is an abrasive reamer, it can be rotated at a high speed by grinding, the processing time can be shortened, and the finishing accuracy of the valve guide hole is improved. can do. In addition, the tool life is increased. In addition, the finishing process can be performed in two stages with the rough finishing abrasive reamer and the finishing abrasive reamer rotating on the same axis with respect to the guide hole pilot hole, reducing the processing load and reducing the valve guide hole Finishing accuracy can be improved.

The invention of claim 1 or claim 2 wherein, after the finishing abrasive reamer has passed through the completely entire length of the valve guide hole, the seat surface processing tool is by that so as to start the machining of the valve seat surface, The processing diameter of the valve guide hole is the same in the length direction without being affected by the wear of the finishing abrasive reamer in the length direction.

  According to the second aspect of the present invention, it is easy to manufacture by using an off-the-shelf processing device by changing the software of the control device that outputs a control signal by applying a contouring motion by orthogonal two-axis feed. can do.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of a machining tool and a machining apparatus used in a method for machining a valve seat surface and a valve guide hole of a cylinder head embodying the present invention will be described with reference to the drawings.
As shown in FIG. 2, a table 11 for supporting the cylinder head 17 is provided on the bed 10. A Z-axis saddle 12 is disposed on the bed 10 so as to be movable in the Z-axis (front-rear) direction by a Z-axis drive mechanism (not shown) that constitutes a forward-backward movement mechanism. A columnar X-axis saddle 13 is supported on the Z-axis saddle 12 by an X-axis drive mechanism (not shown) so as to be movable in the X-axis (right and left, orthogonal to the plane of FIG. 2) direction. A Y-axis saddle (not shown) is mounted on the X-axis saddle 13 so as to be movable in the Y-axis (vertical) direction by a Y-axis drive mechanism (not shown). The spindle device 14 is supported on the Y-axis saddle so as to be oriented in the Z-axis direction. A rotating spindle 15 is rotatably supported on the head portion of the spindle device 14, and a tool holder H holding a processing tool 16 is detachably attached to the rotating spindle 15. Then, the Z-axis saddle 12 is moved closer to and away from the cylinder head 17 on the table 11 while the rotation main shaft 15 is rotated in a state where the rotation main shaft 15 is moved to the lower machining position shown in FIG. The cylinder head 17 is subjected to predetermined processing by the processing tool 16.

Next, the structure of the cylinder head 17 processed by the processing tool 16 attached to the rotating spindle 15 will be described.
As shown in FIG. 4, a cylindrical valve guide 18 is fitted and fixed at a predetermined position of the cylinder head 17 by, for example, press-fitting. A cylindrical guide hole pilot hole 18a is formed in advance on the inner peripheral surface of the valve guide 18 by a drill or the like. The cylinder head 17 has a valve seat 19 having a ring shape so as to be positioned on the same axis as the central axis O1 of the valve guide 18 and corresponding to the intake passage 17a for introducing fuel vaporized into the cylinder. Is fitted and fixed by press-fitting, for example. A seat surface lower hole 19 a is formed in advance on the inner peripheral surface of the valve seat 19 opposite to the valve guide 18 when the valve guide 18 is manufactured. In this seat surface prepared hole 19a, for example, as shown in FIG. 5, the first relief surface 19b in an inclined state located on the outer peripheral side as shown in FIG. 5 and the same inclined state located on the inner peripheral side of the first relief surface 19b The second relief surface 19c is formed in advance. A corner portion 19d that rises in a mountain shape is formed at the boundary portion between the two relief surfaces 19b and 19c, that is, at the position where the sheet surface 19f is formed.

Next, the machining tool 16 for finishing the valve guide 18 and the valve seat 19 will be described with reference to FIG.
As shown in FIG. 1, the processing tool 16 is detachably connected to the tool holder H. A pilot hole processing tool 21 is integrally formed at the tip (left side in FIG. 1) of a stainless steel tool body 16a having a cylindrical shape that forms the processing tool 16. The pilot hole processing tool 21 is a grindstone tool configured by attaching abrasive grains in a cylindrical shape by electrodeposition to a small-diameter cylindrical portion at the tip of the tool body 16a. A tapered portion 21a having a smaller diameter at the tip is integrally formed at the tip of the pilot hole processing tool 21. The tapered portion 21a also has abrasive grains attached to the outer peripheral surface of the tapered portion by electrodeposition.

  A rough-finished abrasive reamer for rough-finishing the pilot hole 18a of the valve guide 18 within a predetermined range rearward from the pilot hole processing tool 21 is provided at an intermediate portion of the tool body 16a of the processing tool 16. 22 is formed. A taper reamer portion 22 a having a smaller diameter at the tip is formed at the step portion between the pilot hole processing tool 21 and the rough finish abrasive reamer 22. Similarly, a finishing abrasive reamer 23 is formed in the middle portion of the tool body 16a for finishing the rough hole-finished pilot hole 18a within a predetermined range behind the rough finishing abrasive reamer 22. The rough finishing abrasive reamer 22 and the finishing abrasive reamer 23 are configured by attaching abrasive grains in a cylindrical shape to the outer peripheral surface of the tool body 16a by electrodeposition.

  As shown in FIG. 13, the length of the rod portion 26 is such that the processing portion 25a of the sheet surface processing tool 25 processes the sheet surface 19f after the finishing abrasive reamer 23 has completely passed through the entire length of the valve guide hole 18e. Is set to start.

  The outer diameter dimension d1 of the pilot hole processing tool 21, the outer diameter dimension d2 of the rough finishing abrasive grain reamer 22, and the outer diameter dimension d3 of the finishing abrasive grain reamer 23 are in a relation of d1 <d2 <d3. As an example, d1 = 5.0 mm. d2 = 5.9 mm and d3 = 6.0 mm are set.

  A seat for forming a conical valve seat surface 19f (see FIG. 13) having an inclination angle of 45 degrees in the seat surface prepared hole 19a of the valve seat 19 at the base end portion of the tool body 16a of the processing tool 16. The surface processing tool 25 is fitted and fixed. On the outer peripheral surface of the sheet surface processing tool 25, a processing portion 25a having a conical shape as a whole with an inclination angle of 45 degrees is formed. The processed portion 25a is formed by a main body and abrasive grains electrodeposited on the outer peripheral surface thereof. Note that a rod portion 26 where no abrasive reamer is present is provided between the rear edge of the finishing abrasive reamer 23 and the front end surface of the sheet surface processing tool 25.

  A plurality of spiral grooves (not shown) are formed on the outer peripheral surfaces of the rough finishing abrasive reamer 22 and the finishing abrasive reamer 23 to form a discharge path for chips and coolant. Further, although not shown, a coolant supply path is formed inside the processing tool 16 so that the coolant is supplied to the tool surface. Also in the sheet surface processing tool 25, although not shown, a discharge path for chips and coolant is formed on the surface, and coolant is supplied to the tool surface from an internal coolant supply path. The coolant may be water or mist. Further, the coolant may be applied from the outside of the processing tool 16.

Next, a control circuit for controlling the operation of the processing apparatus will be described with reference to FIG.
The control device 31 is provided with a central processing unit (CPU) 32 for performing various arithmetic processing operations. The CPU 32 stores a random access memory (ROM) 33 in which an operation program of the processing device is recorded in advance and various data. Is connected to a random access memory (RAM) 34. The control device 31 includes an X-axis linear scale 36 for detecting the position of the machining tool 16 in the X-axis direction, an Y-axis linear scale 37 for detecting the position in the Y-axis direction, and the Z-axis direction via the interface 35. A Z-axis linear scale 38 for detecting the position is connected.

  On the other hand, a plurality of drive circuits 40 are connected to the control device 31 via an interface 39, and an X-axis servo motor 41 for reciprocating the X-axis saddle 13 in the X-axis direction is connected to each circuit 40. Yes. Similarly, a Y-axis servo motor 42 for reciprocating a Y-axis saddle (not shown) in the Y-axis direction is connected to the drive circuit 40. Further, a Z-axis servo motor 43 for driving the Z-axis saddle 12 for feeding and moving the machining tool 16 in the front-rear (Z-axis) direction is connected to the drive circuit 40.

  In the control device 31, the center axis of the rotating processing tool 16 mounted on the rotary spindle 15 using the X-axis servo motor 41 and the Y-axis servo motor 42 is centered on the center axis set in advance at a predetermined position. A contouring motion command section 44 is provided for performing a contouring motion by swiveling.

  Next, the valve guide hole 18e and the valve seat are formed in the pilot hole 18a of the valve guide 18 provided in the cylinder head 17 and the seat surface lower hole 19a of the valve seat 19 using the processing tool 16 and the processing apparatus configured as described above. An operation for finishing the surface 19f will be described.

  First, the X-axis servo motor 41 and the Y-axis servo motor 42 are numerically controlled by a control signal from the control device 31 shown in FIG. 3, and the spindle device 14 including the machining tool 16 is moved in the X and Y axis directions. The center of the spindle is aligned with the center axis O1 when the valve seat surface 19f and the valve guide hole 18e are processed with respect to the cylinder head 17. In this state, the spindle device 14 is moved in the Z-axis direction, and further moved in the X-axis or Y-axis direction to change the central axis O2 of the machining tool 16 from the central axis O1 of the valve guide 18 as shown in FIG. Translate to the offset position. As a result, the tapered portion 21a of the pilot hole processing tool 21 moves to a position corresponding to the corner portion 19d between both relief surfaces 19b and 19c of the valve seat 19, as shown in FIG. In this state, the rotary spindle 15 is rotated to rotate the machining tool 16, and the X-axis servo motor 41 and the Y-axis servo motor 42 are numerically controlled by a control signal output from the contouring motion command unit 44 of the control device 31. To do. Then, the machining tool 16 is swung around the central axis O1 of the valve guide 18 with a predetermined turning radius as shown in FIG. In this state, the Z-axis servo motor 43 is controlled to advance the machining tool 16 in the Z-axis direction, and the taper portion 21a of the pilot hole machining tool 21 chamfers the corner portion 19d between both relief surfaces, thereby forming the taper portion 19e. Form. As a result, the sheet surface 19f can be preprocessed, and the sheet surface processing tool 25 can be ground uniformly without cornering, so that the cutting amount can be reduced.

  Next, the machining tool 16 is returned to the central axis O1 and moved forward to allow the tip of the pilot hole machining tool 21 to enter the opening of the pilot hole 18a of the valve guide 18. Then, with the center axis O1 of the machining tool 16 slightly offset from the center axis O1 of the valve guide 18 as shown in FIG. 7, the pilot hole machining tool 21 is subjected to a contouring motion as shown in FIG. A pilot hole 18b having a predetermined length is formed in the axial direction at the opening edge. Since the pilot hole processing tool 21 performs an accurate circular movement around the center axis O1, even if the pilot hole 18a of the valve guide 18 is in a state of misalignment with respect to the center axis O1, an accurate hole is not followed. It is possible to form the pilot hole 18b that can be processed and whose core misalignment is corrected.

  After the pilot hole 18b is formed, the machining tool 16 is returned to the central axis O1 again, and the machining tool 16 is retracted to set the offset dimension of the central axis O2 from the central axis O1 of the machining tool 16 as shown in FIG. The taper machining part 21a of the pilot hole machining tool 21 is made to correspond slightly to the inner peripheral corner of the opening edge of the pilot hole 18b. In this state, as shown in FIG. 10, the rotating pilot hole machining tool 21 is contoured to chamfer the inner peripheral corner of the opening of the pilot hole 18b by the taper machining part 21a to enter the pilot hole 18b. A tapered portion 18c is formed. Thereby, burrs and corners at the inlet end of the pilot hole 18b are removed.

  Next, as shown in FIGS. 11 and 12, the pilot hole 18b formed in the pilot hole 18a with the center axis O1 of the valve guide 18 and the center axis O2 of the machining tool 16 centered on the same axis again. The pilot hole processing tool 21 and the rough finishing abrasive reamer 22 that rotate on the same axis are entered. Then, the rough finish abrasive reamer 22 sequentially finishes the inner peripheral surface of the pilot hole 18b and the inner peripheral surface of the prepared hole 18a to form a rough finish valve guide hole 18d.

  Finally, as shown in FIGS. 13 and 14, the entire prepared hole 18a of the valve guide 18 is finished by the finishing abrasive reamer 23 of the processing tool 16 rotating on the same axis, thereby forming the valve guide hole 18e. Substantially at the end of the finishing of the valve guide hole 18e, the processed portion 25a of the seat surface processing tool 25 is brought into contact with the tapered portion 19e formed at the corner portion 19d between both relief surfaces of the valve seat 19, and a predetermined angle ( A sheet surface 19f having a predetermined width is formed at 45 degrees.

  According to the processing method, the processing tool, and the processing apparatus for the valve seat surface 19f and the valve guide hole 18e of the cylinder head 17 of the above embodiment, the following effects can be obtained.

  (1) In the above-described embodiment, the pilot hole processing tool 21 is rotated and contoured to form the tapered portion 19e in the pilot hole 19a of the valve seat 19 in advance by the tapered portion 21a. For this reason, the machining allowance at the time of finishing the valve seat surface 19f by the processing portion 25a of the seat surface processing tool 25 becomes uniform with the seat width, the uneven wear of the tool is eliminated, and the tool life is greatly extended. Therefore, the valve seat surface 19f can be smoothly formed by the processing portion 25a of the seat surface processing tool 25, and the processing accuracy of the seat surface 19f can be improved. The cutting portion 25a of the sheet surface processing tool 25 does not hit the burrs or corners, and the cutting amount can be reduced, and the tool life can be maintained long. It is further preferable to form the inclination of the taper machining portion 21a of the pilot hole machining tool 21 at 45 degrees in accordance with the seat surface 19f.

  (2) In the above embodiment, the pilot hole processing tool 21 of the processing tool 16 is rotated and contoured to form the pilot hole 18 b in the pilot hole 18 a of the valve guide 18. Therefore, the pilot hole processing tool 21 partially contacts the inner peripheral surface of the pilot hole 18a to reduce the grinding resistance, and even if the pilot hole 18a has a misalignment, the pilot hole that follows the misalignment of the pilot hole It is possible to eliminate the eccentricity of the processing tool 21 and accurately form the pilot hole 18b in which the core misalignment of the pilot hole 18a is corrected. For this reason, the accuracy of the concentricity between the pilot hole 18b and the seat surface 19f of the valve seat 19 can be improved. Therefore, the abrasive reamers 22 and 23 can be correctly inserted and guided on the central axis O1, the processing accuracy of the valve guide hole 18e by the rough finish abrasive reamer 22 and the finish abrasive reamer 23 can be improved, and the valve guide hole 18e. And the accuracy of the concentricity of the seat surface 19f can be improved.

  (3) In the above embodiment, the tapered portion 18c is formed by rotating and contouring the tapered portion 21a of the pilot hole processing tool 21 at the inner peripheral corner portion of the opening edge of the pilot hole 18b. Further, a taper reamer portion 22 a is provided at the tip of the rough finish abrasive reamer 22. For this reason, the taper reamer 22a provided at the tip of the rough finish abrasive reamer 22 is smoothly cut into the opening edge of the pilot hole 18b, and is accurately fed and guided to the pilot hole 18b. The valve guide hole 18e can be accurately finished by preventing the eccentricity following the pilot hole 18a.

  (4) In the above embodiment, the valve guide hole 18e is processed by the rough finishing abrasive reamer 22 and the finishing abrasive reamer 23. For this reason, compared with finishing at once, the grinding resistance during processing can be suppressed, the machining allowance by the finishing abrasive reamer 23 can be reduced, the tool life can be improved, and the finishing accuracy of the valve guide hole 18e can be increased. Can be maintained for hours.

  (5) In the above-described embodiment, the finishing abrasive reamer 23 of the processing tool 16 and the sheet surface processing tool 25 are integrally configured, and the finishing process (valve guide hole forming step) of the valve guide hole 18e by the reamer 23, the sheet surface The finishing process (seat surface forming process) of the valve seat surface 19f by the processing tool 25 is performed in the same process. For this reason, the accuracy of the concentricity of the valve guide hole 18e with respect to the valve seat surface 19f can be further improved through the processing tool 16 as compared with a method in which both are separated and performed one after the other.

  (6) In the above embodiment, after the finishing abrasive reamer 23 has completely passed through the entire length of the valve guide hole, the sheet surface processing tool 25 starts processing the sheet surface 19f. By doing so, the processing diameter of the valve guide hole 18e is finished with the same high precision in the length direction without being affected by the wear of the finishing abrasive reamer 23 in the length direction.

In addition, you may change the said embodiment as follows.
The pilot hole processing tool 21 and the taper processing portion 21a may be replaced with abrasive grains, and other tools such as an end mill or a reamer with a plurality of blades may be used. Thereby, cutting force can be improved.

The rough finishing abrasive reamer 22 and the finishing abrasive reamer 23 may be replaced with ordinary reamers that do not use abrasive grains.
(Circle) it is good also as a mechanism which incorporated the said reamer or abrasive grain reamer with respect to the sheet | seat surface processing tool 25 so that advancement / retraction was possible.

A cutter may be used in place of the sheet surface processing tool 25 with abrasive grains.
The rough finish abrasive reamer 22 may be omitted.
The seat surface 19f may be processed on the valve seat 19 by the seat surface processing tool 25 in a state where the finishing abrasive reamer 23 does not completely pass through the valve guide hole 18e.

O You may materialize as a type of processing device which separated sheet surface processing tool 25 from processing tool 16.
O You may form the process part 25a of the sheet surface processing tool 25 in a segment form.

A contouring motion imparting mechanism for causing the machining tool 16 to perform a contouring motion may be configured separately.
O You may actualize to the processing apparatus provided with the mechanism which reciprocates the table 11 to a Z-axis direction.

The front view which shows the processing tool used for the process of the valve seat and valve guide of the cylinder head of this invention. FIG. 6 is a schematic front view showing a cylinder head machining apparatus. FIG. 6 is a control circuit diagram of machining operation of the cylinder head. The longitudinal section showing processing operation of a valve seat of a cylinder head. The partial expanded sectional view of the valve seat of FIG. The expanded cross-sectional view explaining the contouring motion of the pilot hole processing tool of FIG. The longitudinal cross-sectional view explaining the processing operation of the pilot hole of a valve guide. FIG. 8 is an enlarged cross-sectional view illustrating the processing operation of the pilot hole processing tool of FIG. 7. The longitudinal cross-sectional view explaining the chamfering process operation | movement of the opening edge inner periphery of the pilot hole of a valve guide. FIG. 10 is an enlarged cross-sectional view illustrating the processing operation of the pilot hole processing tool of FIG. 9. The longitudinal cross-sectional view explaining the processing operation of the rough finish valve guide hole of a valve guide. FIG. 12 is an enlarged cross-sectional view of the rough finish abrasive reamer of FIG. 11. The longitudinal cross-sectional view for demonstrating the finishing process operation | movement of the valve guide hole of a valve guide, and a valve seat surface. FIG. 14 is an enlarged cross-sectional view through the valve guide and the finishing abrasive reamer of FIG. 13.

Explanation of symbols

  d1, d2, d3 ... outer diameter dimensions, 10 ... bed, 13 ... X-axis saddle, 14 ... spindle device, 16 ... machining tool, 16a ... tool body, 17 ... cylinder head, 18 ... valve guide, 18a ... below guide hole Hole, 18b ... Pilot hole, 18c ... Tapered portion, 19e ... Tapered portion, 18e ... Valve guide hole, 19 ... Valve seat, 19a ... Seat surface lower hole, 19b, 19c ... Relief surface, 19d ... Corner, 19f ... Valve Sheet surface, 21 ... Pilot hole processing tool, 21a ... Tapered processing part, 22 ... Rough finishing abrasive reamer, 23 ... Finishing abrasive reamer, 25 ... Sheet surface processing tool, 25a ... Processing part, 31 ... Control device.

Claims (2)

A pilot hole processing tool, rough finishing abrasive reamer and finishing abrasive reamer are provided in order from the tip side on the same axis at the tip of the columnar tool body, and a sheet surface processing tool is provided at the base end of the tool body. valve seat surface of the cylinder head comprising Te and using the processing tool of the valve guide bore, finished by the seat surface processing tool which rotates at the same axis with respect to the preformed sheet surface under the hole in the valve seat provided in the cylinder head finish and the seat surface forming a valve seat surface, the rough finish abrasive reamers and finishing abrasive reamer rotates at the same axis with respect to pre-formed guide hole under the hole in the valve guide which is provided in the cylinder head and processing methods smell of the valve seat surface and the valve guide bore of a cylinder head comprising a valve guide hole forming step of forming a valve guide bore by processing, the ,
Prior to the sheet surface forming step, the taper machining portion formed concentrically at the tip of the pilot hole machining tool is rotated and contoured by rotating and rotating the tool body shaft with respect to the sheet surface pilot hole. To make a tapered part,
Next, the prior to the valve guide hole forming step, the inner peripheral surface of the opening end side of the guide hole pilot hole relative to the rotation of the tip tool body axis set only pilot drilling tool to the tool body Rotating and contouring with a swivel motion to contact and form a pilot hole ,
The tapered portion is contacted with the inner peripheral corner portion on the opening end side of the pilot hole processed by the pilot hole processing tool by rotating and contouring the tool body shaft by rotating and turning motions. Forming,
Then, rough finish and finish with the rough finish abrasive reamer and the finish abrasive reamer rotating on the same axis with respect to the guide hole pilot hole to form a valve guide hole,
After the finishing abrasive reamer passes through the entire length of the valve guide hole and finishes, the seat surface processing tool comes into contact with the tapered portion formed on the valve seat to form the valve seat surface. A method for machining a valve seat surface and a valve guide hole of a cylinder head. A cylinder head support table installed in the bed;
A pilot hole processing tool, rough finishing abrasive reamer, and finishing abrasive reamer are provided on the same axis in this order from the tip side to the tip of the tool body that is mounted on the bed and has a columnar shape. A spindle device for mounting a valve seat surface and a valve guide hole processing tool of a cylinder head provided with a seat surface processing tool in a positively rotatable manner;
A contouring motion imparting mechanism that is mounted between the bed and the spindle device and that imparts a contouring motion to the spindle of the spindle device by rotation and turning motion;
A longitudinal movement mechanism for moving the support table or the spindle device back and forth;
A controller for controlling the operation of the contouring motion imparting mechanism and outputting a control signal for imparting a contouring motion to the machining tool supported by the spindle device;
A control signal is output from the control device to impart a contouring motion to the machining tool by orthogonal two-axis feed to the inner peripheral surface on the opening end side of the guide hole pilot hole previously formed in the valve guide provided in the cylinder head. On the other hand, a pilot hole is formed with a pilot hole processing tool provided at the tip of the tool body, and after the finishing abrasive reamer passes through the entire length of the valve guide hole and finishes, the sheet surface processing tool An apparatus for processing a valve seat surface and a valve guide hole of a cylinder head, wherein the device is configured to contact a valve seat to form a valve seat surface.

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