JPH05169305A - Composite machining apparatus - Google Patents

Abstract

PURPOSE:To reduce the total machining time required from the start of machining both first and second parts to be machined to the machining end in a composite machining apparatus for individually machining the first and second parts to be machined while the rotating speed of a spindle is changed by a first tool and a second tool which are different in the radial position in relation to the axis of rotation of the spindle. CONSTITUTION:A driving motor 22 for a spindle 3 is rotated at low speed, and a feed motor 26 for a first tool 11 and a feed motor 31 for a second tool 20 are operated with low speed feed, so that machining by the first tool 11 is started, and at the same time, machining by the second tool 20 is also started at low speed. After machining by the first tool 11 is ended, a spindle driving motor 22 is switched from the low speed rotation to the high speed rotation, and simultaneously with the switching of rotation, the feed motor 31 for the second tool is switched from low speed feed to high speed feed to perform machining at high speed by the second tool 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a first machining location where extremely strict concentricity is required, such as reprocessing of a valve seat surface and reaming of a valve stem guide hole in machining a cylinder head of an automobile engine. The present invention relates to a combined machining apparatus in which a second machining location and a second machining location are individually machined by different kinds of tools provided on the same main spindle.

[0002]

2. Description of the Related Art As a conventional composite processing apparatus of this type,
For example, a structure as shown in Japanese Patent Laid-Open No. 62-271613 is known.

In this conventional structure, a hollow spindle is rotatably supported by a machining head, and a cutting tool for performing a recessing process on the valve seat surface is attached to the tip of the spindle through a holder and at the same time, a base. A motor for driving the spindle is operatively connected to the end. A sleeve is concentrically inserted into the main shaft so as to be integrally rotatable and relatively movable in the axial direction. A tool holder is operatively connected to the tip of the sleeve, and a tool feeding cylinder is operably connected to the base end of the sleeve. ing. A rod is concentrically inserted into the sleeve so as to be integrally rotatable and relatively movable in the axial direction, and a reamer for reaming the valve stem guide hole is attached to the tip of the rod through a holding body. A reamer feed motor is operatively connected to the base end via a feed screw or the like.

During machining of the cylinder head of the engine, as shown in the time chart of FIG. 7, the main spindle drive motor rotates the main spindle at low speed, and the bite feed cylinder feeds the bite at low speed through the sleeve. When applied, the valve seat surface is processed. After completion of this processing, the rotation of the spindle drive motor is switched from low speed to high speed, and the rotation of the main spindle is accelerated to a speed suitable for reaming. The reamer feed motor is started at the same time when the speed of the spindle drive motor is switched, and the feed speed is increased in synchronization with the rotation speed of the spindle drive motor. The feed is given and the valve stem guide hole is reamed.

[0005]

However, in this conventional combined machining apparatus, the reaming motor is started to start the reamer machining after the recessing machining is completed. There has been a problem that the total processing time T2 required from the start of the process to the end of the reaming process becomes long.

The present invention has been made by paying attention to the problems existing in such a conventional technique, and the purpose thereof is to simultaneously start the machining of the first machining portion by the first tool, It is an object of the present invention to provide a combined machining apparatus capable of starting the machining of the second machining location by the second tool and reducing the total machining time required from the machining start to the machining termination of both machining locations.

[0007]

In order to achieve the above object, according to the present invention, a first machining point and a second machining point are provided by a first tool and a second tool whose radial positions are different from each other with respect to a rotation axis of a main shaft. In a combined machining apparatus that performs machining separately by changing the rotation speed of the spindle at two machining locations, a spindle drive unit that rotationally drives the spindle by switching between low speed rotation for the first tool and high speed rotation for the second tool. A first feed means that relatively feeds the first tool at a low speed; a second feed means that relatively feeds the second tool by switching between a low speed and a high speed corresponding to the rotation speed of the spindle; and a spindle drive. The first feeding means and the second feeding means are operated at a low speed when the low speed rotation of the means is started, and after the machining by the first tool is completed, the second speed is synchronized with the switching from the low speed rotation to the high speed rotation of the spindle driving means. Is the feeding means low-speed feeding? It is provided with a control means for controlling to switch to high speed feeding.

[0008]

[Operation] When machining is carried out in the complex machining device configured as described above, first, the spindle is rotated by the spindle driving means at a low speed suitable for machining the first tool, and
The first feed means is operated at low speed feed, and the first tool is used to machine the first machining location. At this time, when the spindle drive means starts rotating, the second feed means also starts to operate at low speed, and the machining of the second machining location by the second tool also starts at low speed.

When the machining of the first machining portion is completed, the spindle drive means is switched from the low speed rotation to the high speed rotation suitable for machining the second tool, and the second feeding means is also rotated at a low speed in synchronization with the switching of the rotation. The feed can be switched to high-speed feed. Therefore, while the feed amount per unit rotation of the second tool is kept constant, the feed amount is increased as the rotation speed increases, and the second tool performs high-speed machining of the second machining location. ..

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a combined machining apparatus embodying the present invention will be described below in detail with reference to the drawings.

As shown in FIGS. 1 and 2, the processing head 1
Is provided with a head body 2, and a hollow main shaft 3 is rotatably supported in the head body 2 via a bearing 4.
The tool head 5 is fixed to the tip of the spindle 3 with a screw 6,
A pair of rough machining tips 7 and 8 are provided on the outer periphery of the tip end thereof, and an inclined accommodation groove 9 is formed on the front surface. The cutting tool holder 10 is slidably accommodated in the accommodation groove 9, and a cutting tool 11 as a first tool is attached to the tip thereof.

Then, as shown in FIGS. 2 and 3, when the main spindle 3 is rotated and the entire machining head 1 is moved toward a cylinder head C as a workpiece by a feed unit (not shown), rough machining is performed. The valve seat surface S as the first processing location is roughly processed into a substantially conical shape by the chips 7 and 8. Also, after that, while the main shaft 3 is rotated,
When the bite holder 10 slides in the accommodation groove 9 toward the center of rotation of the main shaft 3, the valve seat surface S is conically finished by the bite 11.

As shown in FIGS. 1 and 2, the sleeve 12
Is inserted concentrically into the main shaft 3 so as to be integrally rotatable and relatively movable in the axial direction.
An engagement body 14 that engages with the engagement hole 13 of 0 is fixed by a screw 15. The spring 16 is the pin 1 in the tool head 5.
7 and the sleeve 12, and the spring 16 urges the sleeve 12 to move toward the base end side to hold the bite holder 10 at the outer end position of the accommodation groove 9. Then, when the sleeve 12 is moved to the tip side against the biasing force of the spring 16, the bite holder 10 slides toward the center of rotation of the spindle 3 along the inclined surface of the housing groove 9 via the engaging body 14. To be done.

The rod 18 is inserted into the sleeve 12 concentrically so as to be integrally rotatable and relatively movable in the axial direction, and a collet chuck 19 is provided at the tip thereof. The reamer 20 as the second tool is inserted into the guide bush 21 of the tool head 5 such that the reamer 20 is arranged at a different radial position from the cutting tool 11 with respect to the rotation axis of the main shaft 3, and the base end thereof is the collet chuck 19. Is linked to. Then, when the rod 18 is moved to the tip end side while the main shaft 3 is rotated, the inner surface of the valve stem guide hole G as the second processing location is finished by the reamer 20.

As shown in FIG. 1, a main shaft rotating motor 22 constituting a main shaft driving means is disposed so as to face the base end of the main shaft 3, and a gear transmission mechanism 23 including gears 24 and 25 is provided by the motor 22. The main shaft 3 is rotationally driven via.
An AC inverter motor is used as the main shaft rotating motor 22, and is rotated by switching between low speed rotation suitable for machining the cutting tool 11 and high speed rotation suitable for machining the reamer 20 by well-known frequency conversion or the like. It has become so.

A bite feed motor 26, which is a step motor as a first feed means, is arranged so as to face the base end of the sleeve 12, and the feed screw 27, the nut 28, and the actuating body 29 are rotated by the rotation of the motor 26. The sleeve 12 is moved in the axial direction via the rotary sleeve 30 and the feed is applied to the cutting tool 11. A reamer feeding motor 31 including a step motor as a second feeding means is arranged to face the base end of the rod 18, and the rotation of the motor 31 causes the feed screw 32, the nut 33, the operating body 34, and the rotary sleeve 35. The rod 18 is moved in the axial direction via, and the reamer 20 is fed.

The rotation sensor 36 is the motor 2 for rotating the spindle.
2, the rotation sensor 36 outputs a detection signal of the rotation speed when the motor 22 is rotated. The control circuit 37 that constitutes the control means includes the motors 22 and 2
6, 31 and the rotation sensor 36 are provided, and the control circuit 37 controls the rotation of the motors 22, 26, 31.

Now, the details of the control circuit 37 will be described with reference to FIG.
PU) 41, read-only memory (ROM) 42,
A readable / writable memory (RAM) 43 is provided. The ROM 42 stores programs and the like for controlling the operation of the entire device. Further, the RAM 43 stores low speed and high speed rotation data of the spindle rotation motor 22, low speed feed data of the bite feed motor 26, and low speed and high speed feed data of the reamer feed motor 31.

An input signal from an input unit 44 including a rotation speed setting key, a start key, etc., and a detection signal from the rotation sensor 36 are input to the CPU 41 via an input interface 45. The CPU 41 outputs an output interface 46 to the spindle rotation motor 22, the bite feed motor 26, and the reamer feed motor 31.
The drive and stop signals are output via the drive circuits 47 to 49.

Then, as shown in the time chart of FIG. 6, the CPU 41 causes the spindle rotation motor 22 to rotate at a low speed and the bite feed motor 26 to operate at a low feed rate, so that the bite 11 causes the valve seat surface S to move. When performing the recessing process of the
Simultaneously with the start of the rotation, the reamer feed motor 31 is also operated at a low speed to start the reaming of the valve stem guide hole G by the reamer 20 at a low speed.

As shown in FIG. 4, the CPU 41 moves the cutting tool 11 to the point P when the valve seat surface S is processed, and when the processing is substantially completed, the time chart of FIG. As shown in, the main shaft rotation motor 22 is switched from low speed rotation to high speed rotation, and the rotation of the motor 22 is rotated based on the detection signal from the rotation sensor 36 so that the feed amount per unit rotation of the reamer 20 becomes constant. Reamer feed motor 3 in synchronization with changes
The operation of 1 was changed from low speed feed to high speed feed, and the reamer 20
Reaming of valve stem guide hole G is performed at high speed.

Next, the operation of the combined machining apparatus configured as described above will be described with reference to the flowchart of FIG. 5 and FIG. Now, in this combined machining device, the valve seat surface S of the cylinder head C is roughly conical-shaped by the roughing tips 7 and 8 as the machining head 1 advances, and then the head 1 is stopped at a predetermined position. When finishing the valve seat surface S and the inner surface of the valve stem guide hole G, the spindle 3 is rotated by the spindle rotation motor 22.
Is rotated at a low speed and is maintained at a low speed preset based on the detection signal from the rotation sensor 36 (steps S1 and S2). At the same time, the bite feed motor 26 operates the bite 11 at a low speed, and the bite 11 finishes the valve seat surface S (step S3). Further, when the main shaft rotating motor 22 starts to rotate, the reamer feeding motor 31 causes the reamer 20 to rotate.
Is also operated by low speed feeding, and the inner surface finishing of the valve stem guide hole G by the reamer 20 is started at low speed (step S4). At this time, the feed amount of the reamer 22 is set according to the rotation speed of the main shaft rotation motor 22 based on the detection signal from the rotation sensor 36 so that the feed amount of the reamer 20 per unit rotation becomes constant.

Then, in step S5, it is determined whether or not the recessing process is completed. If YES, in step S6 the rotation of the spindle 3 by the spindle rotation motor 22 is switched from low speed to high speed, and the rotation sensor 36 is rotated. The speed is maintained at a preset high speed based on the detection signal from. When the cutting tool 11 is removed from the seat surface S when the valve seat surface S has been machined, the cutting tool feed motor 26 is stopped.

When the rotation of the main shaft 3 is switched, the feed amount of the reamer 20 per unit rotation is constant.
Based on the detection signal from the rotation sensor 36, the operation of the reamer feed motor 31 is changed from the low speed feed to the high speed feed in synchronization with the rotation change of the motor 22, and the reamer 20 causes the valve stem guide hole G to move to the inner surface at a high speed. Finishing is performed (step S7). Then, in step S8, it is determined whether or not the machining of the guide hole 8 by the reamer 20 is completed. If YES, the machining head 1 is retracted by the feeding unit (not shown), and the bite feed motor 26 and the reamer feed are performed. The rotation motor 31 is reversely rotated, and the cutting tool 11 and the reamer 20 are returned to their original positions (steps S9, 1).
0).

Therefore, according to the combined machining apparatus of this embodiment, the machining of the valve stem guide hole G by the reamer 20 can be started at a low speed at the same time when the machining of the valve seat surface S by the cutting tool 11 is started. Comparing with the conventional processing device in which the machining of the valve stem guide hole G by the reamer 20 is started after the processing of the valve seat surface S by 11 is completed, The total processing time T1 (see FIG. 6) required for the above can be significantly shortened.

The present invention is not limited to the construction of the above-mentioned embodiment. For example, the constructions of the spindle drive means, the first feeding means and the second feeding means may be modified appropriately, or the present invention may be applied to a cylinder head. It is also possible to embody by arbitrarily changing the configuration of each part within a range not departing from the gist of the present invention, such as performing processing of a workpiece different from C.

[0027]

Since the present invention is configured as described above, the machining of the first machining location by the first tool is started at the same time as the machining of the second machining location by the second tool is started. It has an excellent effect that the total processing time required from the start of processing to the end of processing of the processing location can be shortened.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of a combined machining apparatus embodying the present invention.

FIG. 2 is a partial cross-sectional view showing an enlarged configuration of the processing head.

FIG. 3 is an explanatory diagram for explaining a recessing process of a valve seat surface with a roughing tip and a cutting tool.

FIG. 4 is a block diagram showing a control circuit of the combined machining apparatus.

FIG. 5 is a flowchart showing operations of a valve seat surface recessing process and a valve stem guide hole reaming process.

FIG. 6 is a time chart showing the relationship among the spindle rotation, the bite feed, and the reamer feed in the combined machining apparatus of this embodiment.

FIG. 7 is a time chart showing the relationship among spindle rotation, bite feed, and reamer feed in the conventional combined machining apparatus.

[Explanation of symbols]

3 spindle, 11 bite as first tool, 12 sleeve, 18 rod, 20 reamer as second tool,
22 spindle rotation motor as spindle driving means, 26
Bit feeding motor as first feeding means, 31 second
Reamer feed motor as feeding means, 37 control circuit as control means, S valve seat surface as first machining location, valve stem guide hole as G second machining location.

Claims (1)

[Claims] 1. A composite in which a first tool and a second tool having different radial positions with respect to a rotation axis of a spindle are used to individually machine a first machining location and a second machining location while changing the rotation speed of the spindle. In a processing apparatus, a spindle drive unit that drives the spindle to rotate by switching between low-speed rotation for the first tool and high-speed rotation for the second tool, and first feed unit that relatively feeds the first tool at low speed. A second feed means for switching the second tool between a low speed and a high speed corresponding to the rotation speed of the main spindle to relatively feed the second tool; and a first feed means and a second feed means when the low speed rotation of the main spindle drive means is started. And a control means for controlling the second feed means to switch from the low speed feed to the high speed feed in synchronization with the switching of the spindle drive means from the low speed rotation to the high speed rotation after finishing the machining by the first tool. Provided Combined machining apparatus according to claim and.