JPS6020801A - Machining device of cylinder - Google Patents

Abstract

PURPOSE:To high accurately and high efficiently operate a machining device and easily perform its handling, by rotating a cylinder and moving a tool in an axial direction so as to detect a relative position between both the cylinder and the tool and control a difference between said relative position and the preset value to zero, in the case of the machining device of the cylinder for a video tape recorder. CONSTITUTION:Data for forming a head shape on a cylinder are stored in a random access memory (RAM) 35, operating a control circuit 30. In this way, the cylinder 13 is machined to be cut by rotating the cylinder itself and moving a tool in the axial direction of the cyliner. Here a rotary angle of the cylinder detected by a rotary encoder 31 and a moving position of the tool detected by a linear encoder 32 are input to the control circuit 30. The control circuit 30 compares in its comparator 36 a linear encoder signal sampled through a sample hold circuit 34 with a reference signal from the RAM 35, and a motor driving circuit 38 controls a motor M so that a difference between the compared both signals may become zero. In this way, a machining device, being easily handled, can be high accurately and high efficiently opened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a cylinder processing device used for cutting the circumferential surface of a cylinder used, for example, in a video tape recorder.

[Technical background of the invention and its problems]

Generally, a video tape recorder (VTR) has a stepped portion called a reed on the circumferential surface of a lower cylinder, and the reed is used to guide the movement of the camera. For this reason,
Setting the shape of this lead with high precision is extremely important in improving the running stability of the tape.

Therefore, conventionally, leads have been processed using a processing device as shown in FIG. 1, for example.

That is, the cylinder 1 as a workpiece is held by a chuck 2, and the chuck 2 and the crown cam 3 are pivotally attached to the lathe main shaft 4, and the lathe main shaft 4 is rotationally driven to rotate the cylinder 1 and the crown cam 3. It's rotating. On the other hand, a cutting tool 5 as a processing tool is held on a cutting table 6, and the cutting table 6 holding this cutting tool 5 is transferred to a reciprocating table 7.
is attached to. Then, a cam follower 8 fixed to this carriage 7 is brought into contact with and follows the cam surface of the crown cam 2 by means of a compression spring 9, and this moves the carriage 7 back and forth to move the cutting tool 5 onto the circumferential surface of the cylinder 10. is moved axially along the The cutting depth of the cutting tool 5 into the circumferential surface of the cylinder 1 is adjusted by moving the cutting table 6 using a hydraulic mechanism.

However, in order to form the lead 1a on the cylinder 1 using such a device, the cylinder 1 is fixed to the chuck 2 and rotated together with the crown cam 3, and in this state, the cutting tool 5 is moved around the cylinder by a hydraulic mechanism. While pressing against the surface, the cylinder 1 is pressed according to the shape of the cam surface of the crown cam 3.
This is done by moving it in the axial direction.

That is, this device forms a lead by performing tracing using the crown cam 3. Therefore, by appropriately setting the cam shape of the crown cam 3, a desired lead can be formed.

However, such conventional devices have the following various drawbacks. In other words, the disadvantages are: (1) The machining shape changes due to wear of the crown cam 3, which reduces machining accuracy, so it is necessary to periodically correct the shape of the crown cam 3. No. Therefore, maintenance requires a lot of effort and time, and accurate shape correction requires skill.

(11) When the material of the cylinder 1 changes, the lead shape also changes accordingly, so the shape of the crown cam 3 must be corrected each time the cylinder 1 material changes, and in this respect, handling is also difficult. It becomes very troublesome.

(11) Since the reciprocating table 7 must be equipped with a hydraulic mechanism, etc., the structure of the table must be large and heavy, and due to the rigidity of the lathe main shaft 4, the pressing force of the compression spring 9 is limited. Therefore, the reciprocating speed of the cutting tool 5 cannot be increased.

[Purpose of the invention]

The present invention is a cylinder machining device that eliminates the need for complicated and troublesome maintenance, allows for easy and quick response to changes in cylinder material and machining shape, and is easy to handle and capable of precise, highly efficient machining. The purpose is to provide

[Summary of the invention]

In order to achieve the above object, the present invention provides a rotation mechanism for rotating a cylinder, a movement mechanism for reciprocating a processing tool in the axial direction of the cylinder, and detects the rotation angle of the cylinder by the rotation mechanism. A rotation angle detector and a movement position detector for detecting the movement position of the processing tool by the moving mechanism are provided, and the processing position of the processing tool with respect to the cylinder is detected from each detection signal from these detectors, and this processing position is detected. The rotating mechanism or the moving mechanism is drive-controlled in order to compare it with a preset reference value and make the difference zero.

[Embodiments of the invention]

FIG. 2 is a first schematic diagram of a cylinder processing apparatus in an embodiment of the present invention.

In the figure, 11 indicates a main shaft portion, and a chuck 12 is rotatably attached to this main shaft portion 1, and a cylinder 13 as a workpiece is fixed to this chuck 12. . Note that, at this time, the chuck 12 fixes the cylinder 13 by gripping the shaft 13a.

Further, a pulley 14 is rotatably attached to the main shaft portion 11, and this pulley 14 is connected to a drive shaft of a motor as shown in the figure through a belt 15, so that the pulley 14 is rotated by the motor.

On the other hand, No. 2 indicates a 1d fixed stand for supporting the processing tool, and this fixing No. 82 is attached in the axial direction of the cylinder 13 (
A moving base 22 is attached so as to be slidable in the direction indicated by the arrow. A cutting tool 23 as a processing tool is fixed to this moving table 22. Further, an eccentric plate 25 is connected to one end of the moving table 22 via a connecting rod 24, and a servo motor (not shown) is connected to an eccentric shaft 25a of the eccentric plate 25. The moving table 22, connecting rod 24, eccentric plate 25, and servo motor constitute a reciprocating mechanism for the cutting tool 23. The fixed base 21 is mounted on a table (not shown) that is slidable in the direction B, and the depth of cut of the cutting tool 23 into the circumferential surface of the cylinder 13 is adjusted by this table. There is.

Incidentally, a rotary encoder 3 is connected to the main shaft portion 11. This low-return encoder 3 detects the rotational direction of the cylinder 13, and supplies the detection signal to the control circuit 3θ. On the other hand, a linear encoder 32 is installed on the fixed base 2 of the reciprocating mechanism.

This linear encoder 32 detects the amount of movement of the movable table 22 and the movement position of the claw 9 bite 23, and its detection signal is introduced into the control circuit 3o.

FIG. 3 is a circuit block diagram showing the configuration of this control circuit 30. This control circuit 3θ first sends the rotary encoder 3 I(7) detection tJ3 signal (pulse) to the counter 3
3, a sample timing signal is outputted to the sample hold circuit 34 every time a certain number of pulses are counted, and the counted value at that time is supplied to a random access memory (RAM) 35. This R.A.
M35 contains reference information determined according to the lead shape to be formed in the cylinder 13, for example, as shown in FIG. I remember it.

The control circuit 3° is the sample hold circuit 3.
At step 4, the detection signal level from the linear encoder: lr s' z is sampled at the time of generation of the Zan 7° timing signal, and this signal level is led to the comparator 36. Further, the control circuit 30 reads reference information from the address corresponding to the count value output from the counter 33 of the RAM 35, converts this reference information into an analog value with the D/A converter 37, and then sends it to the comparator 36. It has been introduced.

Then, the control circuit 30 uses a comparator 36 to transfer the sample signal level from the sample hold circuit 34 to the RAM 35.
The difference signal is compared with the reference signal level, and the difference signal is sent to the motor drive circuit 38, which generates a drive signal to make the difference signal zero.

The drive signal is then supplied to the servo motor M to control the moving position of the cutting tool 23.

Next, the operation of the apparatus configured as described above will be explained according to the processing procedure. First, before processing, data is stored in RAM 35.
Standard information set according to the lead shape to be formed in the cylinder 13 is stored.

Then, the table on which the fixed base 21 is mounted is moved to bring the cutting tool 23 into contact with the cylinder 13 with a predetermined pressure,
Thereafter, the control circuit 30 is activated by operating a start button (not shown).

Then, the motor for driving the rotation of the cylinder 13 and the servo motor M start driving, and the cylinder 13 rotates and the cutting tool 23 moves in the axial direction (in the direction of arrow A) while being in contact with the cylinder 13. Start. At this time, the rotation angle of the cylinder 13 is detected by a rotary encoder 31, and the moving position of the cutting tool 23 is detected by a linear encoder 32.

Now, during the above operation, in the control circuit 30, each time the cylinder 13 rotates by a certain angle, the counter 33 outputs the sample timing number and the count value information at that time. Then, at the time when the sample timing signal is generated, the detection signal of the linear encoder 32 is sampled in the sample 0/hole 1 circuit 34 and introduced into the comparator 36. At the same time, reference information is output from the RAM 35 addressed by the count value information, converted to an analog signal, and then sent to the comparison circuit 36.
I was kidnapped by 4j. Then, the comparison circuit 36 compares the sample and hold value of the detection signal with the reference information level, and supplies the difference signal to the motor drive circuit 38. As a result, a drive signal created to make the difference signal zero is generated from the motor drive circuit 38, and the servo motor M is driven by this signal to control the moving position of the cutting tool 23. In other words, the moving position of the cutting tool 23 is R
Feedback control is performed to follow the reference information set in AM 35. Therefore, accurate leads are formed on the cylinder 13 in accordance with the above reference information.

As described above, in this embodiment, the p-lead is machined by performing feedback control according to the reference information without using the crown cam. This eliminates the need for complex maintenance and adjustment, and it is extremely easy to handle changes in cylinder material, lead shape, etc. by simply re-memorizing the reference information in RAM. It is possible to provide processing equipment that is Further, as described above, since the machining is performed using feedback control, the machining can be performed with high precision and at high speed, and productivity can be increased. Since the servo converts the rotation of the motor into linear motion using a stone plate, there is no need to change the direction of rotation of the servo motor, which has the advantage of reducing the influence of the inertial force of the moving table.

Note that the present invention is not limited to the above embodiments.

For example, in the above embodiment, the moving position of the cutting tool is feedback-controlled, but the rotation angle of the cylinder may be feedback-controlled. A mushroom table device may be used as the mushroom movement mechanism, and the movement position of the cutting tool may be controlled by driving and controlling this mushroom table device. Furthermore, a linear motor may be used as the moving mechanism. Furthermore, multiple types of reference information are available in advance according to the type of cylinder and shape of the lead.
These standards (R
It is also possible to select and use the information. In addition, a microprocessor may be applied to the control circuit, and the circuit configuration, cylinder rotation mechanism, movement mechanism, etc. can be modified in various ways without departing from the gist of the present invention.

〔Effect of the invention〕

As described in detail above, the present invention rotates a cylinder by a rotating mechanism, moves a processing tool back and forth by a moving mechanism, and detects the rotation angle of the cylinder and the moving position of the processing tool. The processing position of the processing tool on the cylinder circumferential surface is recognized from the result, and the recognized processing position is compared with a preset reference value, and the rotation angle of the cylinder and the movement position of the processing tool are controlled to reduce the difference to zero. It was designed to do so.

Therefore, according to the present invention, since a crown cam is not used, complicated and troublesome maintenance can be avoided, and changes in cylinder material and machining shape can be easily and quickly responded to. It is possible to provide a cylinder machining device that is easy to handle and can perform highly accurate and highly efficient machining.

[Brief explanation of the drawing]

Figure 1 is a schematic configuration diagram of a conventional cylinder processing device.
Figures 2 to 4 show one embodiment of the present invention.
FIG. 3 is a block diagram showing the configuration of a control circuit of the cylinder processing device, and FIG. 4 is a diagram showing an example of reference information. 1... Main shaft part, 12... Chuck, 13... Cylinder, 14... Pulley, 15... Belt, 21... Fixed base, 22... Moving base, 23... Bit, 24・・・
・Connecting rod, 25... Eccentric plate, 3o... Control circuit, 3... Rotary encoder 7, 32... Linear encoder, 33... Counter, 34... Sample hold circuit, 35...・RAM, 36... Comparator, 37
..., D/A converter, 38... motor drive circuit, M
·Servomotor.

Claims (1)

[Claims] A rotation mechanism that rotatably supports and rotates a cylinder as a workpiece, a processing tool that contacts the surface of the cylinder to cut the circumferential surface of the cylinder, and slides this processing tool in the axial direction of the cylinder. a rotation angle detector that detects the rotation angle of a cylinder that is rotated multiple times by the rotation mechanism; and a rotation angle detector that detects the rotation angle of a cylinder that is rotated multiple times by the rotation mechanism; The machining position of the processing tool relative to the cylinder is detected from the detection signals of the movement position detector, the rotation angle detector, and the movement position detector, and the loe position is compared with a preset reference value. A cylinder processing device comprising: a control circuit that drives and controls the rotating mechanism or the moving mechanism to reduce the difference to zero.