JPS5924953A - Barrel grinding device - Google Patents

Abstract

PURPOSE:To maintain constant efficiency of grinding, by rapidly braking a barrel tank to stir media by inertia in the barrel tank after driving the barrel tank to be rotated through a rotation driving gear in accordance with a prescribed program. CONSTITUTION:Abrasive work of media 62 is performed by rotating a work 48 in normal direction through a turning motor 46 while reversely rotating a barrel tank 14 through a driving motor 24 with driving signals of a control driver circuit 58. When the first period of grinding is finished in accordance with a prescribed program, the motor 46 is immediately driven in the reverse direction, and a rapid brake is applied to the driving motor 24 to suddenly stop the barrel tank 14. This brake action causes the media 62 to be fluidized by inertia and violently stirred by both the inside movement of the media 62 palced aside to a peripheral wall by centrifugal force and the slide dropping due to tilting of the barrel tank 14. Thereafter in the second period of grinding, the work and the barrel tank are rotated respectively in the reverse direction to that of the preceding period and the abrasive work is continued. In this way, efficiency of grinding can be suitably maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a barrel processing device that polishes a workpiece by rotationally driving the barrel tank while holding the entire workpiece in a medium housed in a vertical barrel tank with an open top end. In particular, the present invention relates to a barrel processing device that can effectively flow media within a barrel tank.

One type of barrel processing device is a so-called gyro two-barrel processing device. This is the device shown in FIG. In the figure, a rotating shaft l is supported by a bearing 2 so as to be rotatable around a vertical axis, and a vertical barrel tank shaped like a container and containing media 3 is attached to the upper end of the rotating shaft 1. 4 is fixed, and the barrel tank 4 is driven to rotate around a vertical axis. When the workpiece 6 attached to the lower end of the holding device 5 is held in the media 3 at an eccentric position with respect to the center of the barrel tank 4 and the barrel tank 4 is rotated, the workpiece 6 and the media 3 are rotated. The workpiece 6 is polished by the relative movement of the two.

However, in such conventional equipment, the barrel tank 4
When the barrel tank 4 is stopped, the level of the media 3 accommodated therein changes as shown by the broken line in the figure, and
The part into which the workpiece 6 is inserted is only locally stirred during the rotation drive, and most other parts do not move relative to the barrel tank 4, so the media 3 at the bottom of the barrel tank 4 in particular There was almost no flow, and the following problems occurred. That is, (1) among the media 3 in the barrel tank 4, only the media 3 in the vicinity of the workpiece 6 collides with the workpiece 6 and is polished, and wear and fragmentation of the media progresses locally, so that Polishing efficiency decreases. That is, of the media 3 in the barrel tank 4, only the media 3 in the vicinity of the workpiece 6 is used locally, and the media 3 in other parts cannot be used effectively. (No In particular, since the media 3 at the bottom of the barrel N4 hardly flows, there is media slag (sludge) that is crushed by the media 3 there.
Because of the accumulation and fixation, periodic cleaning work inside the barrel N4 was required. Such cleaning work not only requires a lot of man-hours, but also requires a hammer or the like to remove the stuck media slag, making it an extremely troublesome maintenance work.

On the other hand, it has been proposed to insert a stirring rod into the barrel tank 4 and to stir and flow the media 3 in the barrel tank 4 by relative rotation between the stirring rod and the barrel tank 4. However, with this method, not only does the barrel processing device become complicated and the cost of the device increases, but the stirring rod itself may be worn out and damaged, and the damaged stirring rod may collide with the workpiece and cause damage to the workpiece. There is a risk that the media 3 will be defective, and the wear and tear of the media 3 will be accelerated, resulting in the inconvenience of shortening the media replacement cycle.

The present invention has been made against the background of the above circumstances, and its purpose is to provide a barrel processing device that allows the media in the barrel tank to flow easily and suitably.

In order to achieve such an object, the present invention provides a barrel for polishing a workpiece by rotationally driving the barrel tank while holding the workpiece in a medium housed in a vertical barrel tank having a container shape. A processing device, comprising: (]) a rotational drive device that rotationally drives the barrel tank;
2) a rotational braking device that rapidly brakes the rotating barrel; and (3) a rotational control device that inertially flows the media in the barrel in the rotation according to a predetermined program. It is characterized by

In this way, when the barrel tank is braked rapidly,
The media in the barrel tank is forced to flow violently in the circumferential direction due to inertia, and the centrifugal force causes the media that had been gathered toward the outer periphery of the barrel tank to flow all at once toward the inner periphery. Together with the flow,
The media in the barrel tank is made to flow vigorously and is stirred. Therefore, the entire media in the barrel tank is effectively utilized, and polishing efficiency is maintained at a good level. This reduces the time required and eliminates the occurrence of defective workpieces.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

A barrel tank 14 is mounted on the upper surface of the inclined table 12 so as to be rotatably driven around an axis inclined at approximately 30 degrees with respect to the vertical line.

That is, on the top surface of the tilt table 12, a rotating shaft 16 tilted at approximately 30 degrees with respect to the vertical line is rotatably supported by a bearing 18, and at the upper end of the rotating shaft 16 is a container with an open top. A barrel tank 14 made of metal is fixed. The lower end of the rotating shaft 16 is connected to the
It is connected to a drive motor 24 as a rotational drive device fixed to the tilt table I2, and the barrel tank 14 can be rotated in forward and reverse directions by the drive motor 24.

A container 26 is fixed on the slope 12 below the barrel tank 14 to receive the coolant;
The coolant collected at one end of the sloping gutter 28
It is designed to be stored in a tank (not shown) through the tank. A cover 34 having a top plate 32 spaced apart by a slight distance lv from the upper end surface of the barrel tank 4 is fitted into the container 26, and as the barrel tank 14 rotates, the cover 34 Splashing of coolant etc. is prevented. A nozzle 36 for injecting coolant into the barrel tank 14 is fixed to the top plate 32 of the cover 34, and a lower end portion of the holding device 38 is fixed to the top plate 32 of the cover 34 to hold the workpiece 48 at an eccentric position in the barrel tank 14. A through hole 40 is provided to allow the passage of.

The holding device 38 includes a guide rod 4 fixed in the vertical direction.
2, and is fixed to an upper and lower frame 44 that is supported movably in the vertical direction by a cylinder 2, and is driven in the vertical direction by a vertical cylinder (not shown). The upper end of the holding device 38 is connected via a chain to a rotating motor '46 fixed to the upper F frame 44.
The lower end of the holding device @38, which holds the workpiece 48, can be rotated in forward and reverse directions. Furthermore, when the holding device @38 is moved upward, its upper end is pressed in the F direction by an opening/closing cylinder (not shown), and the workpiece 48 is released by the opening/closing cylinder. .

Incidentally, a plurality of wire meshes 5o are provided on the outer circumferential wall of the barrel tank 14 so that coolant and media slag can be discharged, and the rotating shaft 16 is passed vertically through the wire mesh 5o to connect the barrel tank 1.
A discharge hole 52 that opens at the bottom of the interior of 4, and the discharge hole 52 thereof.
A conical porous member 54 is provided to cover the opening of the drain hole 52, so that coolant and media slag can be suitably discharged also through the discharge hole 52.

It is now possible to

On the other hand, from the operation/detector 56 that detects the position state of each movable part such as the position of the upper and lower frames 44 and the operation state of the operation device such as a push button or foot switch, the position state of the movable MS and the operation state of the operation device are detected. The state signal 8J representing the control drive circuit 5
8. The control drive circuit 58 sends electric power signals SD1 and SD2 to drive the drive motor 24 and the rotary motor 4 to drive or brake the rotation in a predetermined rotational direction based on a predetermined program according to the status signal SJ.
Supply to 6.

The control drive circuit 58 is constituted by a sequence circuit shown in FIG. 2, for example. Here, drive motor 2
4 and the rotary motor 46 are three-phase AC (direction) motors, and 60 is an electromagnetic brake unit as a rotary braking device. The electromagnetic brake unit 60 supplies a full DC current to one phase of a coil for forming a rotating magnetic field within the AC motor, forms a DC magnetic field within the AC motor, and brakes the rotor of the AC motor by eddy current braking. This is a well-known method for rapidly braking a motor, after the voltage supplied to its input terminal 0 is removed, DC power is supplied from its output terminals + and - to one phase of the coil of the drive motor 24 for a certain period of time. is configured to supply. In addition, the electromagnetic brake unit 60
is equipped with a timer that controls the time for supplying DC power to the drive motor 24, and is equipped with a confirmation contact AC60 that is normally closed but remains open during the period when target power is being supplied. attitude.

The present invention will be explained in detail below.

When the power supply voltage from the transformer Trl is supplied to each group of relays in FIG. 2 by a circuit not shown in conjunction with the start-up operation of the device, the relays MS4 and M-86 are activated, and the rotation motor 46 and the drive motor 24 are activated. Power is supplied. Therefore, the workpiece 48 is rotated around a vertical axis, and the nocrel tank 14 is rotationally driven in a direction opposite to the rotational direction of the workpiece 48. Then, when the seven upper and lower frames 44 are lowered according to another control circuit (not shown), the workpiece 48 is inserted into the media 62 housed in the barrel tank 14. As a result, the workpiece 48 is polished by the media 62 rotating together with the barrel tank 14. FIG. 1 shows this state.

In such a state, Cu5, which is a contact point of a relay (not shown),
A timer TR10, identified by P, Cu3P, and Cu3P and connected in series to their contacts, starts counting time during the polishing state. The set time of the timer TRIQ is determined corresponding to the first polishing period A. When the set time of timer TRIQ has elapsed and timer TR1Q is activated for a limited time), its time-limited contact is activated to deactivate relays MS4 and M3C, and at the same time, relay MS5 is activated. Therefore, as shown by the broken line in FIG. 3, the rotary motor 46 is driven in the opposite direction immediately after the first polishing period A ends. On the other hand, due to the non-operating state of relay MS6, the voltage supplied to the input terminal O of the electromagnetic brake unit 60 is removed, so the electromagnetic brake unit 6
0 immediately supplies DC power to the drive motor 24, and the 3rd M
As shown by the solid line, the drive motor 24 and the barrel tank 14 are suddenly stopped, and the confirmation contact AC6 (l
Open to open the time limit contact of timer 'r tt 16 x. Section B in FIG. 3 shows this state.

In such a state, the media 6 in the barrel tank 14
2 returns to the static position shown by the dashed line in FIG. 1, but in the process, the media 62 is rapidly agitated. That is, when the barrel tank 14 is braked rapidly, the media 62, which had been gathered to the outer periphery of the barrel tank 14 by centrifugal force, tries to move toward the inner periphery according to gravity, and also moves toward the inner periphery according to inertia. flow in the direction.

It slides down to the side. For this reason, the tank 1
The media 62 in the medium 4 is agitated extremely efficiently due to the complex and simultaneous combination of these dominant flows. Furthermore, such agitation becomes even more noticeable when the rotational direction of the workpiece 48 is changed during the braking period B and when the barrel tank 14 is started in reverse, which will be described later, following the braking period B.

At the same time as the DC output of the electromagnetic brake unit 60 is stopped, the confirmation device 4AO60 is closed and the timer T-box 16X starts measuring time. After a very short set time of timer TR16X has elapsed, when the time limit contact of timer Ta16x is closed, relay M-87 is activated. Therefore, the power signal SDI for driving the drive motor 24 to rotate in the direction opposite to the rotation direction of the first polishing period A is applied to the drive motor 24.
4, and the barrel tank 14 is driven to rotate. As a result, the work 48 is polished again until the power to the group of relays shown in FIG. 2 is cut off by a timer (not shown). Section C in FIG. 3 indicates the second polishing period. Then, when the second polishing period ends, relay MS5. When MS7 is rendered inactive, rotation motor 46 and drive motor 24 are stopped.

In this way, according to this embodiment, by applying sudden braking to the barrel tank 14, the media 62 in the barrel tank 14 is caused to flow by inertia, and the media 62, which had been drawn toward the outer circumference by centrifugal force, is moved to the inner circumference. As a result, the media 62 in the barrel tank 14 is suitably fluidized and agitated.

Moreover, since the barrel tank 14 is rotated around an inclined rotation axis, the media 62 located at the upper part of the barrel tank 14 slides down to the lower side, and the flow of the three components works together to push the media 62 even more violently. is stirred. Therefore,
The entire media 62 in the barrel tank 14 is effectively utilized, and the polishing efficiency is suitably maintained, and the wear of the media 62 caused by the stirring bar is reduced compared to a device that is inserted into the barrel tank 14 with a stirring bar. This prevents crushing, thereby preventing shortening of the period for replacing the media 62, and completely eliminates workpiece defects caused by the stirring rod.

Further, according to this embodiment, the barrel tank 14 is restarted in the opposite direction following the sudden braking of the barrel tank 14, and the workpiece 480 is rotated in the opposite direction at the time of sudden braking, so that the media 62 is further It has the advantage of being vigorously stirred.

Furthermore, according to the present embodiment, when the barrel tank 14 is suddenly braked, the wire mesh 50 provided in the barrel tank 14 and the media 62 are moved relative to each other along the surface of the wire mesh 50, so that the wire mesh 50 is not clogged. There is an advantage that the media 62 and media slag can be suitably removed.

Next, another embodiment of the present invention will be described. In the following description of F, parts common to those of the previous embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the processing cycle of the above-described apparatus, after the second polishing period C in which the barrel tank 11 is reversed, a sudden braking period Di may be provided in which the barrel tank 14 is suddenly braked again. That is, as shown in FIG. 4, the barrel tank 14 is rotated forward in the first polishing period A, then braked in the 11'# sudden braking period B, and then f# I″Iφ≠1 layer 1-11
During the second mochi polishing period C-, the 18th surface is rotated in the opposite direction to the previous polishing period, and furthermore, during the braking period, the barrel tank 14 is suddenly braked again. .

According to this embodiment, since the barrel tank 14 is suddenly braked twice in one processing cycle, the barrel tank 14
There is an advantage that the media 62 inside can be stirred at once.

Although the embodiment of the present invention has been described above based on the drawings, the present invention can also be applied to other aspects.

For example, although the barrel tank 14 in the above embodiment is configured to be rotated around an inclined rotation axis, the barrel tank 14 may be configured to be rotated around a vertical axis. Methias 62 in the tank 14 can be stirred by sudden braking of the barrel tank 14.

It is undesirable that the machining cycle of the barrel machining device includes many sudden braking periods, but it is sufficient if at least one sudden braking period is included in one machining cycle.

In the above embodiment, an AC motor is used as the drive motor 24, and an electromagnetic brake unit 60 is used to brake the drive motor 24.
Various means are used to brake suddenly. for example,
The drive motor 24 may be a DC motor, and the DC motor may be braked rapidly by dynamic braking or reverse start braking. Further, a mechanical braking device may be provided between the drive motor 24 and the barrel tank 14, or a so-called brake motor, which is a motor with a braking function, may be used.

Further, in the above embodiment, the rotational direction of the workpiece 48 is changed during the sudden braking period B, and the barrel tank 14 is restarted in the opposite direction following the sudden braking period B. However, even if there is no reversal of the workpiece 48 and no activation of the barrel tank 14 in the reverse direction following the sudden braking period B, a certain stirring effect can be obtained.

It should be noted that the above is just one embodiment of the present invention,
The present invention can be modified in various ways without departing from its spirit.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing essential parts of an embodiment of the present invention. FIG. 2 is a diagram showing a main part of the control drive circuit provided in the embodiment of FIG. 1. FIG. 3 is a time chart showing the operation of the drive motor and rotary motor of the device shown in FIG. FIG. 4 is a time chart showing the operation of the drive motor in another embodiment of the present invention. Fifth
The figure is a sectional view of a main part of a conventional barrel processing device. 14: Barrel tank 16: Rotating shaft 24: Drive motor (drive device) 48: Work 60: Electromagnetic brake unit (rotary braking device) 62:
Media Applicant Toyota Motor Corporation Kyoho Manufacturing Co., Ltd. Figure 2-319

Claims (1)

[Scope of Claims] (1) A barrel processing device that polishes a workpiece by rotationally driving the barrel tank while holding the workpiece in a medium housed in a vertical barrel tank shaped like a container. a rotational drive device for rotationally driving the barrel tank; a rotational braking device for rapidly braking the entire rotating barrel tank; -C1 causing the rotational drive device to rotate the barrel tank according to a predetermined program; and a rotation control device that causes the rotational braking device to rapidly brake the barrel to inertially brake the media in the barrel; Barrel processing equipment characterized by stirring by braking. (2) The rotational drive device is an induction motor, and the rotational braking device is an electromagnetic brake that forms a DC magnetic field in the induction motor to rapidly brake the rotation of the induction motor. Barrel processing equipment described in. (8) +3iJ rotation control device causes the rotation braking device to rapidly brake the barrel tank, and then causes the rotation drive device to rotationally drive the barrel tank in a rotation direction opposite to the previous rotation direction. A barrel processing device according to claim 1 or 2. (4) The rotation control device causes the rotation drive device to rotate the barrel tank in a rotation direction opposite to the previous rotation direction, and then causes the braking device to rapidly brake the rotation of the barrel tank again. Barrel processing bag @0 according to claim 3, wherein the workpiece is placed in the medium at mJ
The workpiece is driven to rotate about an axis substantially parallel to the rotation axis of the barrel tank, and the rotation control device causes the rotation braking device to brake the rotation of the barrel tank, and at the same time, the workpiece is rotated from the previous position. The barrel processing device according to any one of claims 1 to 4, which rotates in a reverse direction.