JP2512403B2 - Gear square chamfer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear square chamfering machine for chamfering the inner and outer teeth of a gear.

2. Description of the Related Art A conventional gear square chamfering machine is disclosed in, for example, Japanese Patent Laid-Open No. 62-130122. According to this, an indexing device for intermittently indexing the gear material at a predetermined pitch and a forward-backward moving mechanism for moving the chamfering cutter back and forth in synchronization with the indexing device are provided. This back-and-forth moving mechanism is a mechanical one using a rotary cam that continuously rotates from a drive motor that operates with a general AC power source via a belt drive and a gear mechanism. In such devices, conventionally, the indexing start command to the indexing device is issued at a position where the chamfering cutter is completely separated from the gear material (workpiece) (even if the indexing device indexes the gear material, When the detection dog provided on the rotary cam is confirmed with a detection switch such as a proximity switch, it is output at a position where it does not interfere with the cutter, for example, at the retracted end of the chamfering cutter.

According to the above, according to the above, since the rotary cam is driven from the drive motor through the gear mechanism and the belt drive, the rotation cam itself has uneven rotation, and the detection dog faces the detection switch at a certain timing. It greatly varies. Also, the detection switches themselves have different detection timings due to temperature and the like, and eventually, due to these factors, the output timings of the detection signals greatly vary, and the start of the indexing operation also varies. Therefore, chamfering may not be performed accurately.

Also, with such a mechanical forward / backward movement mechanism, it is difficult to finely and accurately control the forward / backward movement of the chamfering cutter. Therefore, the operation time when chamfering one tooth is The chamfering cutter completes the chamfering at the machining completion position, and then the chamfering cutter retracts with the gear material stopped and the gear material reaches the position where it does not interfere even if the gear material performs the indexing operation independently. Time to escape from t1 Chamfering cutter time to stop the next tooth of gear material from indexing t2 After chamfering indexing, the chamfering cutter, which was in the non-interfering position, is fast-forwarded to the specified machining start position. Time t3 is the sum of the cutting time t4 from the machining start position to the machining completion position, and the time other than the cutting time and the indexing time is long and the machining time for one tooth is long.

An object of the present invention is to solve these problems.

Means for Solving the Problems According to the present invention, an indexing device that rotatably supports an indexing shaft, to which a gear member as a work is attached at the tip, is arranged on a bed, and the indexing shaft is provided. The cutter shaft head device is arranged so that the cutter shaft head can be moved back and forth by the forward / backward movement device by inclining at a predetermined angle horizontally with respect to the axis line of the In a gear square chamfering machine for chamfering tooth end faces of a material, a screw shaft in which the indexing device is operated by a numerically controlled first motor, and the longitudinal movement device is connected to a numerically controlled second motor. According to the position detection signals from these detecting means, the indexing position detecting means and the front-back position detecting means are connected to the indexing device and the screw feeding device, respectively. For one tooth end face After the chamfering is completed, when the chamfering cutter is inside the plane including the tooth end face in the gear material, the gear material is indexed in conjunction with the retreat of the chamfering cutter, and the chamfering cutter is outside the plane. After retracting to the escape position, the chamfering cutter retracted to the escape position is fed to the cutting start position inside the plane by the time the indexing of the next tooth end surface of the gear material is completed. Two
It is characterized by comprising a control device for controlling the motor.

Action According to the above, the numerically controlled motor causes the gear material to be indexed and the chamfering cutter to move back and forth in an extremely fine and accurate manner, thereby performing an accurate chamfering process. Further, after the chamfering is completed for one tooth end face, when the chamfering cutter is inside the plane including the tooth end face of the gear material, the gear material is indexed in conjunction with the retreat of the chamfering cutter to start chamfering. After retracting the cutter to the escape position outside the plane, feed the chamfering cutter retracted to the escape position to the cutting start position in the plane by the time the indexing of the next tooth end surface of the gear material is completed. Therefore, the indexing operation and the forward / backward movement of the chamfering cutter can be performed in parallel, and the processing time is shortened.

Embodiment In FIG. 1, an indexing device 10 and a cutter shaft head device 50 are arranged on a bed 1. In the indexing device 10, an indexing shaft head 12 fixed to a base 11 fixed on the bed 1 has an indexing shaft 13 rotatably supported. A drawbar 15 is axially slidably inserted into the stepped hollow hole 14 of the indexing shaft 13 and is biased rearward by a spring 16. An arbor 18 of a collet chuck 17 is connected to the draw bar 15, and the collet chuck 17 is detachably fixed to the tip of the indexing shaft 13. In this collet chuck 17, the piston rod 21 of the unclamp cylinder 20 arranged on the upper surface of the indexing shaft head 12 pushes the first lever 22, and the first lever 22 swings to move the indexing shaft.
The second lever 23 in 13 is tilted forward, and the drawbar 15 is spring-loaded.
It moves forward against 16 and is unclamped. On the other hand, when the pressurized fluid supplied to the unclamp cylinder 20 is removed from the unclamped state, the piston rod 21 is retracted (state shown in FIG. 1), and the spring 24 force in the unclamp cylinder 20 causes the first lever 22 to move. Away from the second lever 23, the spring
The 16 lever causes the second lever 23, together with the drawbar 15, to pass through the through hole 25.
The arbor 18 is drawn into contact with the trailing edge of the rear end to clamp the gear material (workpiece) G. At the rear end of the indexing shaft 13, a speed reducer 26 having a large reduction ratio, for example, Harmonic Drive (trademark) is connected. This device is, as is well known, a wave generator consisting of an elliptical cam and a ball bearing fitted on its outer circumference, a flexspline consisting of a cup-shaped metal elastic body having a large number of teeth on its outer circumference, and a flexspline tooth on its inner circumference. And a circular spline having one to two more teeth than that. The circular spline is on the indexing shaft head 12, the flexspline is on the indexing shaft 13, and the wave generator is the first.
Each is connected to the servomotor M1.

Next, in front of the indexing device 10, a cutter shaft head device 50 is arranged so as to be inclined at a predetermined angle horizontally with the axis L of the indexing shaft 13. In this cutter shaft head device 50, a pair of tracks 52 are provided side by side on a base 51. The linear rolling guide 54 on the lower surface of the cutter shaft head 53 is guided to the track 52. This straight rolling guide 54
Is a well-known bearing built-in, which is pre-loaded and guided to the track 52 without rattling left and right. Ball screw nut 55 attached to the bottom of the cutter shaft head 53
A screw shaft 56 is screwed in. Screw shaft 56 is the base
It is rotatably supported at the rear end of 51 and is further connected to the second servomotor M2 via a coupling 57 behind it. The ball screw is preloaded in order to prevent axial play. Thus, the screw feed device 60 that moves the cutter shaft head 53 back and forth by the rotation of the second servomotor M2 is configured.

A drive shaft 61 is rotatably supported by the cutter shaft head 53, and the drive shaft 61 is, for example, disclosed in JP-A-48-9387 and JP-B-45-75.
Two chamfering cutters (hereinafter, cutters) 63 rotatably supported at the tip of the cutter shaft head 53 are rotated in opposite directions via an appropriate gear train 62 as disclosed in No. 7. There is. The two cutters 63 are for simultaneously machining the tooth end surfaces of the gear material G at the top and bottom of the gear material. The two cutter axes K and the indexing axis L intersect at a predetermined angle as shown in FIG. 4 (ii). The drive shaft 61 is connected to a drive motor M (not a servo motor) by belt transmission. Encoders E1 and E2 for detecting the rotation amounts of the first and second servomotors M1 and M2 are connected as indexing position and front-back position detecting means, respectively.

Next, the control device for the first and second servomotors M1, M2
A pulse signal generator 71 and a servo motor controller 72 are provided. The pulse signal generator 71 mainly consists of CPU, ROM, RAM, I / O.
A well-known microcomputer including an interface
73 and keyboard 7 connected to this I / O interface
It consists of 4 and. A program according to the flowchart of FIG. 3 is stored in advance in the ROM, and each step of the flowchart constitutes functional means. That is, step 1 is cutter cutting feed commanding means, step 2 is cutting completion determining means, step 3 is all-tooth machining completion determining means, step 4 is cutter quick return commanding means, step 5 is safety distance determining means described later, step 6 Is an indexing movement commanding means for the indexing axis, step 7 is a cutter escape position determining means, step 8 is a cutter stop and indexing axis fast feed command outputting means, step 9 is a non-interfering position determining means for the indexing axis, step Reference numeral 10 is a cutter fast-forward command output means, step 11 is an index completion determination means, and step 12 is a cutter escape command output means. Further, data necessary for executing the program is input in advance from the keyboard 74 and stored in the RAM. The data required for this program are roughly as follows.

Safety distance (Y1): The cutter 63 is used to compensate for variations in pulse signal output (though this variation is extremely small).
Amount of retreat when the tool is slightly retracted from the machining completion position, 0.1 m
m or less.

Moving ratio: When the indexing shaft 13 is operated in conjunction with the backward movement of the cutter 63 after the cutter 63 has retracted from the chamfered surface G3 by the safe distance Y1, prevent the cutter 63 and the indexed tooth from interfering with each other. Rotational movement amount of the rotatable indexing shaft 13 relative to the retracted amount of the cutter Relief position (Y2): The cutter 63 is the tooth end surface G1, G of the gear material G
See the figure 4 (v), the position where it escapes completely outside the plane containing 2.

Non-interference position (X2): machined tooth T ₁ of the gear member G is rotated, at a position of the middle of the teeth T ₂ of the following raw is indexed, the cutter 63 is advanced to the cutting start position Y3 will be described later Even
Indexing position for tooth T ₁ that does not interfere with machined tooth T ₁ , see FIG. 4 (vi).

Cutting start position (Y3): Position where the cutter 63 changes from fast feed to cutting feed. At this position, the tip of the cutter 63 normally enters inside the plane including the tooth end surfaces G1, G2 ... Of the gear material G. See FIG. 4 (i).

Cutting completion position (Y4): Machining completion position of the cutter 63, see FIG. 4 (ii).

 Number of teeth (Z): This determines the indexing angle.

Cutter feed speed, index speed: Related to the above operation.

The I / O interface allows the servo motor control unit 72 of the first and second servo motors to exchange data and commands bidirectionally, and the servo motor control unit 72 detects the position from the encoders E1 and E2. A signal is input.
Each servo motor control unit 72 is composed of a known position loop servo system and a speed loop servo system, and a servo signal is generated by a pulse signal from the pulse signal generator 71 and a feedback signal (position detection signal) from the encoders E1 and E2. The first and second servomotors M1 and M2 are drive-controlled. The I / O interface is the unclamp cylinder 20.
Controller for controlling the operation of the drive motor M
It is connected to exchange signals with the 80.

When the cutter shaft head 50 is at a standby position (gear material replacement position) A, which is largely separated from the indexing device 10, a sequence control device
In response to the command of 80, the unclamp cylinder 20 is operated and the work (gear material) G is clamped by the collet chuck 17. Next, the drive motor M rotates to rotate the cutter 63, and at the same time, the cutter shaft head 53 is advanced by the screw shaft 56 in response to a command from the control device 70, and the cutter 63 rotatably supported by the cutter shaft head 53 causes the teeth to move. Square chamfering of the end face G1 is performed. At this time, since numerical control is performed using the screw feed device 60 and the indexing device 10 by the first and second servomotors M1 and M2, the position control can be performed with high accuracy.

The chamfering process will be described with reference to FIGS. One of the teeth T ₁ of the gear material G is indexed and stopped at a predetermined machining position facing the cutter 63, and the cutter 63 has already advanced from the standby position A to the cutting start position Y3. . In FIG. 4, L indicates the central axis of the indexing shaft 13. In the flowchart of FIG. 3, in step 1, the command pulse is output only to the second servo motor M2, and the cutter
Set 63 as the cutting feed. (FIG. 4 (i)). Encoder that the cutter 63 has reached the cutting completion position Y4 in step 2
The cutting feed is stopped based on the position detection signal from E2 (Fig. 4 (ii)). In step 3, it is confirmed whether or not all the teeth have been processed. If the processing is completed, the cutter 63 is released to the standby position A in step 12 and the processing is completed. If machining is to be continued, in step 4, the pulse command is issued only to the second servomotor M2 while the indexing shaft 13 is stopped, and the cutter 63 is quickly returned.
In step 5, it is determined whether or not the cutter 63 has retracted by the safe distance Y1 based on the position detection signal from the encoder E2 (FIG. 4 (iii)). When the safe distance Y1 is moved, a pulse command is output to the first servomotor M1 so that the indexing operation is performed by the predetermined moving indexing in step 6. As a result, the chamfered surface G3 and the cutter 63 are linked and indexed without interfering with each other,
Retreat (Fig. 4 (iv)). Then, in step 7, it is determined by the position detection signal from the encoder E2 that the cutter 63 has reached the escape position Y2 (FIG. 4 (v)). Then, in step 8, the second servo motor M2 is stopped and only the first servo motor M1 is rotated at high speed (this "high speed" means
It means that it is not regulated by the movement rate and is faster than that). In step 9, the teeth T ₁ that has been processed by the position detection signal of the encoder E1 indexing to determine whether a non-interference position X2. When the non-interference position X2 is reached, a command is issued again to the second servo motor M2 in step 10, the cutter 63 is fast-forwarded from the escape position Y2 to the cutting start position Y3, and the indexing operation is continued during this time (Fig. 4 ( vi)). And step
Check out indexing completed in 11, the process returns to step 1, the corner chamfering the tooth end faces G2 of the teeth T _2. Hereinafter, a series of these operations is repeated to chamfer all tooth end surfaces of the gear material G.

By such numerical control, the movement and position control of the indexing shaft 13 and the cutter 63 are made highly accurate, and the start of the indexing operation is controlled by the cutter.
Since 63 is started from the time when it is still inside the plane including the tooth end faces G1, G2 ..., it is necessary to wait until the cutter 63 retreats to the complete escape position Y2 and perform indexing as in the past. In comparison, the time spent chamfering one tooth is shortened. Also,. Since the cutter is sent to the cutting start position before the indexing is completed, the cutting process can be started at the same time as the indexing is completed, and in this respect also, the time spent for chamfering is shortened.

In this embodiment, the servomotor is used as the numerically controlled motor, but instead of this, a stepper motor that operates directly with a pulse signal may be used. Further, as the forward / backward movement position detecting means, instead of the encoder, the cutter shaft head position may be directly detected as a reference scale.

As described above, in the gear square chamfering machine of the present invention, numerical control of the indexing of the gears and the back-and-forth movement of the chamfering cutter is performed numerically based on the signals of the position detection means provided for each, by the motor of the numerical control. As a result, the variation in signal exchange is extremely small compared to the conventional proximity switch and the like, and the forward / backward movement and the indexing operation can be synchronized very accurately. for that reason,
Accurate chamfering can be performed. Also, from the time when the chamfering cutter is inside the plane including the tooth end faces of the gear material until the chamfering cutter is located outside the plane including the tooth end faces, the chamfering cutter does not interfere with the teeth of the gear material. Since the indexing and the backward movement are performed at the same time, the indexing operation can be started immediately after the completion of cutting, and the indexing start timing can be advanced as compared with the conventional case. In addition, in the present application, the chamfering cutter is fed from the escape position outside the plane including the tooth end faces to the cutting start position inside the plane including the tooth end faces of the gear material by the time the indexing is completed. Therefore, the cutting is started at the same time as the indexing is completed, and the conventional time for sending to the cutting start position after the indexing can be omitted. Therefore, by advancing the index start timing and omitting the feed time,
The machining time per tooth is shortened, the machining time for one gear material is significantly shortened, and the production efficiency can be increased.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of the present invention, FIG. 2 is a front view of a cutter shaft head device, FIG. 3 is a flowchart of chamfering processing, and FIG. 4 is an operation explanatory diagram showing a relationship between a gear material and a chamfering cutter. , First
FIG. 4 is an enlarged development view of IV in the figure. 10 ... Indexing device, 13 ... Indexing shaft, 50 ... Cutter shaft head device, 53 ...
Cutter shaft head, 56 ... Screw shaft, 60 ... Screw feed device (forward / backward movement device), 63 ... Chamfering cutter, 70 ... Control device, 71 ... Pulse signal generator, 72 ... Servo motor control device, M1, M2 ... No. 1,
Second servo motor, E1, E2 ... Encoder (index position detecting means, front-back position detecting means), G ... Gear material (workpiece), G1
・ G2 ... Tooth end face

Claims (1)

(57) [Claims] 1. An indexing device for rotatably supporting an indexing shaft having a gear member as a work attached to the tip thereof is arranged on a bed, and the indexing device is arranged horizontally with respect to the axis of the indexing shaft. A cutter shaft head device that tilts at a specified angle to move the cutter shaft head back and forth by a back and forth moving device is arranged, and the chamfering cutter provided on the cutter shaft head that moves back and forth is used to chamfer the tooth end surface of the gear material. In the gear square chamfering machine, the indexing device is operated by a numerically controlled first motor, and the forward / backward moving device is a screw feed device by a screw shaft connected to a numerically controlled second motor. The indexing device and the screw feeding device are respectively connected with indexing position detecting means and front-back position detecting means, and based on position detection signals from these detecting means, chamfering for one tooth end face is performed. After completion, the chamfer cutter When the gear material is indexed in conjunction with the retreat of the chamfering cutter at a time inside the plane including the tooth end face of the car material, and after the chamfering cutter is retracted to the escape position outside the plane, A control device for controlling the first and second motors is provided so that the chamfering cutter retracted to the escape position is fed to the cutting start position inside the plane by the time the indexing of the next tooth end surface of the gear material is completed. Gear square chamfering machine characterized by