JPH021626B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is capable of indexing and rotating a rotary table so that a workpiece attached to the rotary table stops at a position that accurately corresponds to a work unit installed on a fixed table. The present invention relates to an indexing rotary automatic working device.

Problems to be Solved by the Prior Art and the Invention A rotary table on which a plurality of jigs are arranged at regular angular intervals is indexed and rotated, and each jig is sequentially applied to each of a plurality of work units installed on a fixed table. Indexing rotation of a rotary table in an indexing rotary automatic work device that automatically performs work such as machining, assembling or removing parts, or measuring workpieces held in each jig by starting and stopping the workpieces. In this method, a protrusion consisting of a straight part with a lead angle of 0 and sloped parts with a large lead angle connected to each other at both ends is spirally wound so that the sloped parts at both ends are parallel to each other and correspond to each other. A peripheral cam such as a roller gear cam or a barrel cam that has been formed is connected to a rotating shaft of a motor, and two adjacent followers of followers protruding at equal intervals from a rotating body, etc. that is connected to an output shaft that is connected to the rotation center of a rotary table. 1 piece
The protrusion of the outer cam is held between the follower of the set, and the output shaft stops together with the rotating body while the follower is engaged with the linear part of the protrusion of the outer cam that rotates at a constant speed due to the drive of the motor. When the follower engages with the inclined part of the protrusion, the output shaft rotates by a predetermined angle together with the rotating body, and when the next set of followers grips the protrusion and engages with the straight part, the output shaft rotates again. An output shaft angle indexing device with a stop is used.

In such devices, the indexing accuracy of the output shaft is determined by the accuracy with which the follower is attached to the rotating body, but there is a certain level of accuracy in the machining accuracy of the follower attachment hole drilled in the rotating body. There is a limit,
It is impossible to improve the indexing accuracy of the output shaft beyond the machining accuracy, and furthermore, if there is an error in the mounting position of each jig with respect to the rotary table and the mounting position of each work unit with respect to the fixed table, It is not possible to accurately match the workpiece held by the tool to the work unit.

However, in general automatic indexing and rotation type work, there are differences in the positioning accuracy of each jig required depending on the work unit, and it is difficult to accurately position each jig for a specific work unit. For example, some errors are often allowed for other work units.

The present invention is intended to be applied to such cases, and can be applied even if there is an error in the attachment of each follower to the rotating body, an error in the attachment of the work unit to the fixed table, and an error in the attachment of each jig to the rotary table. It is an object of the present invention to provide a device that allows each jig to correspond accurately to a specific one of a plurality of work units.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings.

In FIG. 1, a rotary table 12 that is indexed and rotated at 60 degree intervals is installed on a horizontal fixed table 11 stretched over the upper surface of a base 1, and a workpiece (not shown) is held on this rotary table 12. Six jigs 13 are installed at intervals of 60 degrees, and each jig 1 is placed at a position corresponding to the stop position of each of the jigs 13 on the fixed table 11.
A work unit 14 is installed for performing work such as processing, assembling or removing parts, or measuring workpieces held at 3.

A rectangular housing 10 installed on the lower surface of the rotary table 12 houses an outer circumferential cam 2 fixed to a horizontal shaft 21 and a rotating body 3 fixed to a vertical shaft 31 at a height corresponding to the horizontal shaft 21. The respective shafts 21 and 31 are supported by bearings (not shown) and are rotatably supported. The outer cam 2 has a horizontal axis 21
A protrusion 23 with a trapezoidal cross section is spirally wound around the outer periphery of a cylindrical main body 22 that is fitted onto the outside of the body. A gently sloped part 24 that is slightly sloped with respect to the center line , 26 correspond to each other in parallel. The rotating body 3 has a vertical axis 3
Six pins 33 are attached to the outer periphery of the main body 32 fitted on the outer surface of the main body 32.
are installed radially at equal angular intervals of 60 degrees, and a roller 35, which is a follower, is fitted to each pin 33 via a needle bearing so that it can rotate freely. The protrusion 23 of the outer circumferential cam 2 is tightly held by the set, and the protrusion 23 of the outer cam 2 is tightly fitted between the steeply inclined parts 25 and 26 at both ends of the cam 2. The output shaft 30 is fixed to the rotation center of the rotary table 12, and the end protruding from one side of the housing 10 of the horizontal shaft 21, which forms the rotation center of the outer cam 2, is connected to the output shaft 30 from the control device 6. The output shaft of a pulse motor 4 driven by an output signal is connected, and the other end of the horizontal shaft 21 has a third
As shown in the figure, an angle detection device 5 such as an encoder that detects the rotation angle of the horizontal shaft 21, that is, the outer cam 2, is installed. A display 19 is provided to confirm the angle.

Each jig 13 of the work unit 14 described above
An indicator mounting shaft 16 oriented toward the center of the rotary table 12 is mounted on the surface corresponding to each jig 13 of one particular actuating unit 14a, which requires positioning accuracy corresponding to At the same time, each jig 13 is attached to the surface corresponding to the actuating unit 14a of each jig 13.
A measuring shaft 15 is provided whose axial center exactly coincides with the axial center of the mounting shaft 16 when each of the measuring shafts is made to correspond accurately to the working unit 14a.

As shown in FIG. 3, the control device 6 includes a pulse oscillator 56 that generates a pulse signal that serves as a drive source for the pulse motor 4, and a preset numerical value that is subtracted by the pulse signal from the pulse oscillator 56 and a subtracted value. The gate of the command pulse game circuit 58 is opened until the pulse oscillator 56 becomes 0.
A subtraction counter 57 inputs a pulse signal from the input signal to an amplifier 59, and a rotary switch 6 attached to the output shaft 30 inputs a plurality of stored values in the storage device 53 inputted by the keyboard switch 50 and stored.
A data select circuit 54 selects one by one according to the signal from 1 and presets it in the subtraction counter 57.
An amplifier 59 is connected to input its output signal to the pulse motor 4.

Next, the operation of this embodiment will be explained.

When the manual drive command switch 52 shown in FIG. 3 is turned on, the command pulse gate circuit 58 opens only while the switch 52 is turned on, and the pulse generator 56
The pulse signal oscillated from
and the rotating body 3 and rotating table 12 that engage with this.
rotates and turns off the manual drive command switch 52.
The command pulse gate circuit 58 is closed, the pulse signal is stopped, the pulse motor 4 is stopped, and the rotary table 12 is stopped.The manual drive command switch 52 is turned on to rotate the rotary table 12, and the rotary table 12 is rotated. As shown in FIG. 1, the manual drive command switch 52 is turned off at an angle where the first jig 13 approximately corresponds to the specific work unit 14a, the rotary table 12 is stopped, and the mounting shaft 16 of the work unit 14a is turned off. Then, by attaching a test indicator 17 used to measure the degree of deviation of the axes of two axes on the same straight line and rotating the mounting shaft 16 once, the mounting shaft 1 of the work unit 14a is adjusted.
6 and the measuring shaft 15 of the jig 13, and based on the measurement results, the rotary table 12 is adjusted by operating the manual drive command switch 52 so that these axes correspond accurately. The rotation angle of the outer circumferential cam 2 at that time is read on the display 19 of the angle detection device 5, and the value is inputted by the keyboard switch 50 and stored in the storage device 53. By performing the above operation sequentially for each jig 13 after the second one, all the jigs 13
The rotation angle of the outer cam 2 that exactly corresponds to the specific working unit 14a is stored in the storage device 53.

Then, the indexing command switch 5 shown in FIG.
1 starts the indexing operation. Before going into the explanation of the operation, the rotation operation of the rotary body 3 by the outer cam 2 will be explained with reference to FIG. 2. When the control motor 4 rotates the outer cam 2 in the direction of the arrow A shown in FIG. , the set of rollers 3
5a, 35b are pushed along the slope of the gently sloped part 24 of the protrusion 23, the rotating body 3 rotates at a very low speed in the direction of the arrow B, and the rollers 35a, 35b move along the steeply sloped part of the protrusion 23 at one end. When it reaches 25, roller 3
5a and 35b are rapidly pushed along the inclination, the rotating body 3 is rapidly rotated in the same direction, and the next pair of rollers 35b and 35c are pushed along the steep slope at the other end of the protrusion 23. 26 and the outer cam 2 continues to rotate, this pair of rollers 35b, 35c grips the gently sloped portion 24 of the protrusion 23, and the rotating body 3 rotates in the same direction at a very low speed. When the cam 2 rotates once, the output shaft 3 along with the rotating body 3
0 is rotated 60 degrees.

As shown in FIG. 1, when the command switch 51 is turned on while the first jig 13 is stopped in correspondence with the work unit 14a, the data selection circuit 54 is attached to the output shaft 30. Based on the position signal from the rotary switch 61, the value corresponding to the indexing angle of the second jig 13 is selected from among the values stored in the storage device 53, and that value is preset in the subtraction counter 57, and the pulse is The input value of the subtraction counter 57 is sequentially subtracted by the pulse signal input from the oscillator 56, and a signal is output to open the command pulse gate circuit 58 until the subtracted value becomes 0, and the pulse oscillator 56 oscillates. The pulse signal is input to the amplifier 59, and the amplified drive pulse is applied to the pulse motor 4.
When the outer cam rotates, the rotary table 12 rotates at a high speed due to the engagement of the rollers 35, 35 of the rotating body 3 with the steeply inclined parts 25, 26 of the protrusion 23, and the subtraction counter 57 is rotated. When the subtraction value becomes 0, the command pulse gate 58 closes and the pulse signal stops, the pulse motor 4 and the outer cam 2 driven thereby stop, and the second jig 13 is accurately attached to the work unit 14a. The rotary table 12 stops at the corresponding position, but when the jig 13 approaches the indexed position, the roller 3 of the rotary body 3
5 and 35 are placed in the gently inclined portion 24 of the protrusion 23, and the rotating body 3, that is, the output shaft 30 rotates at a very low speed, so the rotary table 12 stops without any inertial force acting on it. After stopping for a time input in advance to the index command switch 51, the data select circuit 54 is activated, and the numerical value corresponding to the next index position detected by the rotary switch 61 is transferred from the storage device 53 to the data select circuit 54. is called, and the next allocation is performed by the same operation as above.

In this embodiment, the absolute value of the rotation angle of the outer cam 2 is fed back from the angle detector 5 to the subtraction counter 57, and the actual rotation angle of the outer cam 2 is compared with the command value. In some cases, the value is input to the subtraction counter 57, and the pulse motor 4 is rotated for correction to match the actual rotation angle of the outer cam 2 with the command value, but such an error may occur. If there is no danger, there is no need to feed back the actual rotation angle of the outer cam 2 to the subtraction counter 57.

In the above embodiment, the absolute value of the rotation angle of the outer cam 2 is stored, but the deviation angle from the standard rotation angle (360°) of the outer cam 2 is stored as a correction value, and the correction The value may be added to or subtracted from the subtraction counter 57.

Further, the motor that drives the outer cam 2 is not limited to the pulse motor 4 of this embodiment,
Other control motors such as a servo motor, variable speed motor, brake motor, etc. may also be used.

Furthermore, in the above embodiment, a roller gear cam that engages with a follower 35 that projects radially on the outer periphery of the rotating body 3 is used as an outer peripheral cam that indexes and rotates the output shaft 30. It is also possible to apply a barrel cam that engages with a protruding follower.

Structure and effects of the invention As specifically explained in the above embodiments,
The indexing rotary automatic working device of the present invention has a protrusion on the outer circumferential surface in which steeply inclined parts with a large lead angle are connected to both ends of a gently inclined part with a small lead angle, and the steeply inclined parts are parallel to each other. The outer cam is spirally wound to correspond to the outer cam, a control motor that can drive the outer cam and stop it at any angle, and a plurality of followers protruding at equal intervals. The protrusion is held between the two driven elements, and while the follower engages with the steeply sloped part of the protrusion due to the rotation of the outer cam, the follower rotates at a high speed, and is rotated at a high speed while it is engaged with the steeply sloped part of the protrusion. a rotating body that rotates at a very low speed while engaged; a rotary table connected to the rotating body and having a plurality of jigs arranged at regular angular intervals; at least one work unit that is installed on a fixed table so as to correspond to a jig and performs work such as processing, assembling or removing parts, or measuring a workpiece held by the jig; and the outer peripheral cam. an angle detection device that detects a rotation angle of the rotary table;
a storage device that stores the rotation angle of the outer circumferential cam at a position where each of the jigs or the workpiece held by each of the jigs corresponds to one of the work units; The main feature of this system is to consist of a control device that controls the rotation and stopping of a control motor, and a gently sloped part with a minute lead angle is provided on the protrusion of the outer cam to finely adjust the stopping position of the output shaft. At the same time, the control motor is controlled based on each pre-stored rotation angle of the outer cam at a position where the jig or each workpiece held therein corresponds to one of the work units. Because of this, even if there is an error in the attachment of each follower to the rotating body or an error in the attachment of each jig to the rotary table, the workpiece held on each jig can be accurately handled for that one specific work unit. In addition, at the angle at which the rotating body stops, the follower engages with the gently sloped part of the protrusion of the outer cam where the lead angle is minute, and the rotation angle of the rotating body relative to the rotation angle of the outer cam is adjusted. Since the rotation angle is extremely small, it is possible to reduce the angle error of the rotating body even if an angle detection device such as an encoder with relatively low measurement accuracy is used to measure the rotation angle of the outer cam. If the relative positions of the work unit or work units change and the relative positions become incorrect, accurate indexing operation can be maintained by correcting each rotation angle of the outer cam stored in the storage device. Achieve the desired effect.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention;
FIG. 2 is a developed view of the outer cam, and FIG. 3 is a block diagram of the control system. 2: Outer cam, 4: Control motor, 5: Angle detection device, 6: Control device, 11: Fixed table, 1
2: rotary table, 13: jig, 14: work unit, 23: protrusion, 24: gentle slope, 25,2
6: Steep slope, 30: Output shaft, 35: Roller, 5
3: Storage device.

Claims (1)

[Scope of Claims] 1. A protrusion on the outer circumferential surface, which has a gently sloped part with a small lead angle and a steeply sloped part with a large lead angle connected to both ends,
an outer circumferential cam wound spirally so that the steeply inclined portions correspond to each other in parallel; a control motor capable of driving the outer circumferential cam and stopping the outer circumferential cam at an arbitrary angle; Followers are protruded at equal intervals and the protrusion is held between the two followers, and the speed is high while the follower engages with the steeply inclined part of the protrusion due to the rotation of the outer cam. a rotary table that is connected to the rotary body and has a plurality of jigs arranged at regular angular intervals; At least a part that is installed on a fixed table corresponding to the jig in the slow rotation range of the rotary table and performs work such as processing, assembling or removing parts, or measuring the workpiece held by the jig. one working unit, an angle detection device that detects the rotation angle of the outer cam, and a slow rotation range of the rotary table,
a storage device that stores the rotation angle of the outer circumferential cam at a position where each of the jigs or the workpiece held by each of the jigs corresponds to one of the work units; An indexing rotary automatic work device comprising: a control device that controls rotation and stop of a control motor;