JPH0473538B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) This invention relates to a balance display device for a rotary workpiece in a machine tool.

(Prior Art) No prior art corresponding to this invention has been found.

(Problems to be Solved by the Invention) An object of the present invention is to enable the balance state of a rotary workpiece to be recognized at a glance.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a first display body capable of displaying the amount of runout at each index position, and a rotary workpiece at each index position. a second indicator that indicates the state by a predetermined sign other than a numerical value when the amount of runout of the camera falls below a predetermined value; A control means for controlling the operation of the controller is provided.

(Function) Now, when the rotary workpiece of the machine tool is rotated and the balance indicator is activated, the amount of runout of the rotary workpiece at a plurality of index positions is detected by the detection means based on the rotational direction origin detected by the origin setting means. be done. Then, the amount of runout is displayed on the first display by the control means, and when the amount of runout of the rotary workpiece becomes equal to or less than a predetermined value, the state is displayed on the second display.

(Example) Hereinafter, an example in which the present invention is embodied in a surface grinder will be described based on the drawings.

As shown in FIG. 1, a table 2 for holding a work W is provided on a frame 1 of a grinding machine. A support shaft 4 shown in FIG. 2 is rotatably mounted on the table 2, and a rotating grindstone 3 is fixed to the tip thereof so as to face the workpiece W on the table 2 from above. A motor 6 for driving the support shaft 4 is arranged behind the support shaft 4.

A piezoelectric acceleration pickup 5 is attached to the upper column 1a of the frame 1. Further, as shown in FIG. 2, a detection piece 7 is provided protruding from the outer periphery of the base end of the support shaft 4, and an origin consisting of a photo interrupter 9 is provided on the frame 1 outside the base end of the support shaft 4. A detection sensor 8 is provided and outputs an origin detection signal each time the detection piece 7 passes through this portion.

Note that the frame 1 includes all parts except the part rotated by the motor 6.
Further, the acceleration pickup 5 has a magnet (not shown), and is attracted to a part of the frame 1 by the magnet. Therefore, acceleration pick-up 5
The installation position can be changed freely.

A display 10 is arranged and fixed on the outside of the frame 1, and a power switch 11 is provided on the side surface of the display 10 for turning the balance detection device of this embodiment on and off.

As shown in FIG. 3, the front surface of the display 10 is a display section 12, and the display section 12 shows a total of 36 indexing positions for every 10 degrees of rotation angle, corresponding to each indexing position of the grinding wheel 3. The display bodies 13 are arranged in a ring. Each indexing position display body 13 has a built-in red light emitting diode. Further, an origin indicator 14 having a built-in light emitting diode is arranged to correspond to an index position indicator 13 for the angular position at which the origin detection sensor 8 generates a signal.
A runout amount display unit 15 is provided within the ring of the indexing position display body 13, and a runout amount display unit 15 that numerically displays the runout amount of the grinding wheel 3 based on blinking of seven liquid crystal segments for one character is provided. A good balance status indicator 16 is provided within the ring that lights up when the amount of deflection at each index position is stable, that is, when the condition is appropriate, and a hold indicator 17 is further provided to indicate a display hold status. .
These display bodies 16 and 17 each have a built-in light emitting diode.

Further, a hold switch 19 for holding the display is arranged on the upper right side of the display section 12.

FIG. 4 shows a block diagram of the balance detecting device in this embodiment, and the components of this circuit excluding the acceleration pickup 5 are the display 10.
Built inside. Central processing unit (CPU)
) 20 is connected to an input/output device (to be described later) via an input/output port (hereinafter referred to as I/O) 21, a read-only memory (hereinafter referred to as ROM) 22, and a random access memory (hereinafter referred to as RAM) 23. A control circuit 30 is formed. The input/output device includes a filter circuit 24, an origin detection sensor 8, a hold switch 19, a power switch 11 as input devices, and an index position indicator 13, an origin indicator 14, a deflection amount indicator 15, and a balance as output devices. A good condition indicator 16 and a hold indicator 17 are connected. Also, ROM2
Programs are stored in RAM 23, and a data area for storing data is provided in RAM 23.

A piezoelectric acceleration pickup 5 for detecting vibrations of the frame 1 is connected to the filter circuit 24. As shown in FIG. 5, the filtering circuit 24 includes a charge amplification circuit 25 which converts the electric charge of the piezoelectric acceleration pickup 5 into an acceleration signal SG1, a voltage amplification circuit 26 which adjusts vibration sensitivity with a variable resistor R1,
A bandpass filter (BPF) 32 that adjusts to synchronize with the vibration of the grindstone 3 using a variable resistor R2, an integrating circuit 33 that converts the acceleration signal SG1 into a speed signal SG2, and a voltage amplification circuit 34 that adjusts the amplification factor of the speed signal SG2. are connected in this order. The speed signal SG2 output from this filter circuit 24 is converted into a digital signal by an A/D converter 28.

The operation of the balance display device configured as above will be explained. First, the operation of the control circuit 30 built into the balance display 10 along with the detectors 5 and 8 will be explained according to the flowchart of FIG. This flowchart proceeds under the control of the CPU 20 according to a program stored in the ROM 22.

Now, when the motor 6 is started with the rotary whetstone 3 attached to the support shaft 4 and the support shaft 4 and the rotary whetstone 3 are rotated, initial settings are made in step S1, and in step S2, the support shaft 4 starts to rotate steadily. A determination is made as to whether or not it has been reached. At this time, the determination is made by measuring the pulse interval of the origin detection pulse output from the origin detection sensor 8, storing the data in the pulse interval area of the RAM 23 for the specified number of rotations, and storing the data within the next specified number of rotations. of
The CPU 20 compares the pulse intervals, and if the pulse intervals are almost the same, the process moves to the next step S3. If the pulse interval data do not match, the count is restarted from the beginning. In step S3, the process waits for the origin signal to be output from the origin detection sensor 8, and simultaneously proceeds to step S4.

In steps S4 to S9, as much runout data D of the rotary grinding wheel 3 as can be processed by the A/D converter 28 is stored in the RAM 23 while the grinding wheel 3 makes one rotation, and at the same time as the grinding wheel 3 completes one rotation, step S1
Go to 0. At this time, in step S5, it is determined whether or not the shake amount data D contains a lot of noise. If measurement is impossible, the shake amount display 15 displays this.

In this step S10, the detected runout amount data D is divided into runout amount data Dn for every 10 degrees based on the total number of runout amount data D, and in step S11, the runout amount data Dn divided for every 10 degrees are divided for each index position. The sum of the data for each indexed position is calculated, and the averaged data Sn is calculated from the number of data. In step S12, the data averaged for each index position is
Store Sn in RAM23. Then, in step S13, it is determined whether or not the set number of revolutions has been repeated. If it has been repeated, the process advances to the next step S14; otherwise, the process returns to step S2 and steps S2 to S13 are repeated until the set number of revolutions is reached.

In step S14, the average data Sn at each indexed position is read out from the RAM 23, and the average data for the set number of revolutions is read out for each indexed position.
Sn is added and average data Yn is calculated for each indexed position from the set rotation speed, and the average data Yn is stored in the RAM 23 in step S15.

Steps S16 to S18 are performed within a specified number of rotations of the grindstone 3. In this step S16, the maximum runout amount and its respective indexed positions (hereinafter referred to as angles) are selected by comparing the average data Yn,
In step S17, maximum runout range angular position setting and maximum runout amount conversion are performed. This maximum runout range angle position setting is to set a tolerance range for the maximum runout amount.
This means selecting an angle whose amount of runout is within the allowable range. Further, the maximum shake amount conversion means converting the shake amount into an amount that can be displayed on the shake amount display 15.

In step S18, it is determined whether or not the maximum runout amount obtained in step S16 is greater than or equal to a reference value. If it is greater than or equal to the reference value, the process proceeds to step S19; if it is not greater than or equal to the reference value, that is, the balance of the rotating grindstone is It is determined that the condition has been removed, and step S2
Proceed to step 1, and as a signal to indicate the completion of balancing,
The good balance indicator 16 is turned on.

Further, in step S19, the maximum deflection amount and deflection angle obtained in step S17 are displayed on the display section 12, and in step S20, when the hold switch 19 is turned on, the display state is maintained, and a hold is held to indicate the maintenance state. The display 17 is turned on. When the hold switch 19 is off, the process returns to step S2, the next balance state is displayed again, and this operation is repeated.

Next, the display state of the display 10 will be explained. At the same time as the power switch 11 is turned on, "..." is displayed on each digit of the runout amount display section 15 until the rotational speed is stabilized. Furthermore, if the shake amount data D has a lot of noise, "BAD" is displayed. Then, as the rotation of the grindstone 3 becomes stable, the runout amount display 15 is displayed at each set rotation speed.
The amount of runout is displayed on the index position indicator 13.
causes the light emitting diode at the maximum deflection angle position to blink. At this time, if the amount of deflection at each angular position is less than the reference value and the rotary grindstone 3 is balanced, the light emitting diode of the well-balanced state indicator 16 is turned on.

The origin indicator 14 lights up when the grindstone 3 passes the origin position.

Therefore, this balance display device can display the maximum unbalance position and its amount of runout, and can easily recognize the good condition of the rotary grindstone.

Effects of the Invention As detailed above, the present invention has the advantage that the unbalance of the rotary workpiece can be easily recognized and the proper state of the rotary workpiece can be recognized at a glance.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view of the balance display device installed on the grinding machine, Fig. 2 is a partial sectional view of the support shaft, Fig. 3 is a front view of the indicator, and Fig. 4 is a block diagram of the control circuit. , Figure 5 is a block diagram of the filter circuit,
FIG. 6 is a flowchart. In the figure, 3 is a rotary workpiece, 4 is a support shaft, 5 is a detection means, 6 is a motor, 8 is an origin setting means, 15
1 is a first display body, 16 is a second display body, and 20 is a control means.

Claims (1)

[Scope of Claims] 1. A support shaft 4 rotated by a motor 6, a rotary workpiece 3 attached to the support shaft 4, an origin setting means 8 for setting the origin of the rotation direction of the rotary workpiece 3, A machine tool equipped with a detection means 5 for detecting the amount of run-out of the rotary workpiece 3 at a plurality of index positions based on the origin, a first display 15 capable of displaying the amount of run-out at each of the index positions. and a second indicator 16 that displays the state with a predetermined sign when the amount of deflection of the rotary workpiece 3 at each of the index positions falls below a predetermined value, based on the signal from the detection means 5. 1. A balance display device for a rotary workpiece in a machine tool, characterized in that a control means 20 for controlling the operation of the first and second display bodies 15 and 16 is provided.